Comparative study of air-conditioning energy use of four office buildings in China and USA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Xin; Yan, Da; An, Jingjing

Energy use in buildings has great variability. In order to design and operate low energy buildings as well as to establish building energy codes and standards and effective energy policy, it is crucial to understand and quantify key factors influencing building energy performance. Here, this study investigates air-conditioning (AC) energy use of four office buildings in four locations: Beijing, Taiwan, Hong Kong, and Berkeley. Building simulation was employed to quantify the influences of key factors, including climate, building envelope and occupant behavior. Through simulation of various combinations of the three influencing elements, it is found that climate can lead tomore » AC cooling consumption differences by almost two times, while occupant behavior resulted in the greatest differences (of up to three times) in AC cooling consumption. The influence of occupant behavior on AC energy consumption is not homogeneous. Under similar climates, when the occupant behavior in the building differed, the optimized building envelope design also differed. In conclusion, the optimal building envelope should be determined according to the climate as well as the occupants who use the building.« less

Comparative study of air-conditioning energy use of four office buildings in China and USA

DOE PAGES

Zhou, Xin; Yan, Da; An, Jingjing; ...

2018-04-05

Energy use in buildings has great variability. In order to design and operate low energy buildings as well as to establish building energy codes and standards and effective energy policy, it is crucial to understand and quantify key factors influencing building energy performance. Here, this study investigates air-conditioning (AC) energy use of four office buildings in four locations: Beijing, Taiwan, Hong Kong, and Berkeley. Building simulation was employed to quantify the influences of key factors, including climate, building envelope and occupant behavior. Through simulation of various combinations of the three influencing elements, it is found that climate can lead tomore » AC cooling consumption differences by almost two times, while occupant behavior resulted in the greatest differences (of up to three times) in AC cooling consumption. The influence of occupant behavior on AC energy consumption is not homogeneous. Under similar climates, when the occupant behavior in the building differed, the optimized building envelope design also differed. In conclusion, the optimal building envelope should be determined according to the climate as well as the occupants who use the building.« less

Building Energy Modeling and Control Methods for Optimization and Renewables Integration

NASA Astrophysics Data System (ADS)

Burger, Eric M.

This dissertation presents techniques for the numerical modeling and control of building systems, with an emphasis on thermostatically controlled loads. The primary objective of this work is to address technical challenges related to the management of energy use in commercial and residential buildings. This work is motivated by the need to enhance the performance of building systems and by the potential for aggregated loads to perform load following and regulation ancillary services, thereby enabling the further adoption of intermittent renewable energy generation technologies. To increase the generalizability of the techniques, an emphasis is placed on recursive and adaptive methods which minimize the need for customization to specific buildings and applications. The techniques presented in this dissertation can be divided into two general categories: modeling and control. Modeling techniques encompass the processing of data streams from sensors and the training of numerical models. These models enable us to predict the energy use of a building and of sub-systems, such as a heating, ventilation, and air conditioning (HVAC) unit. Specifically, we first present an ensemble learning method for the short-term forecasting of total electricity demand in buildings. As the deployment of intermittent renewable energy resources continues to rise, the generation of accurate building-level electricity demand forecasts will be valuable to both grid operators and building energy management systems. Second, we present a recursive parameter estimation technique for identifying a thermostatically controlled load (TCL) model that is non-linear in the parameters. For TCLs to perform demand response services in real-time markets, online methods for parameter estimation are needed. Third, we develop a piecewise linear thermal model of a residential building and train the model using data collected from a custom-built thermostat. This model is capable of approximating unmodeled dynamics within a building by learning from sensor data. Control techniques encompass the application of optimal control theory, model predictive control, and convex distributed optimization to TCLs. First, we present the alternative control trajectory (ACT) representation, a novel method for the approximate optimization of non-convex discrete systems. This approach enables the optimal control of a population of non-convex agents using distributed convex optimization techniques. Second, we present a distributed convex optimization algorithm for the control of a TCL population. Experimental results demonstrate the application of this algorithm to the problem of renewable energy generation following. This dissertation contributes to the development of intelligent energy management systems for buildings by presenting a suite of novel and adaptable modeling and control techniques. Applications focus on optimizing the performance of building operations and on facilitating the integration of renewable energy resources.

Optimization of Energy Efficiency and Conservation in Green Building Design Using Duelist, Killer-Whale and Rain-Water Algorithms

NASA Astrophysics Data System (ADS)

Biyanto, T. R.; Matradji; Syamsi, M. N.; Fibrianto, H. Y.; Afdanny, N.; Rahman, A. H.; Gunawan, K. S.; Pratama, J. A. D.; Malwindasari, A.; Abdillah, A. I.; Bethiana, T. N.; Putra, Y. A.

2017-11-01

The development of green building has been growing in both design and quality. The development of green building was limited by the issue of expensive investment. Actually, green building can reduce the energy usage inside the building especially in utilization of cooling system. External load plays major role in reducing the usage of cooling system. External load is affected by type of wall sheathing, glass and roof. The proper selection of wall, type of glass and roof material are very important to reduce external load. Hence, the optimization of energy efficiency and conservation in green building design is required. Since this optimization consist of integer and non-linear equations, this problem falls into Mixed-Integer-Non-Linear-Programming (MINLP) that required global optimization technique such as stochastic optimization algorithms. In this paper the optimized variables i.e. type of glass and roof were chosen using Duelist, Killer-Whale and Rain-Water Algorithms to obtain the optimum energy and considering the minimal investment. The optimization results exhibited the single glass Planibel-G with the 3.2 mm thickness and glass wool insulation provided maximum ROI of 36.8486%, EUI reduction of 54 kWh/m2·year, CO2 emission reduction of 486.8971 tons/year and reduce investment of 4,078,905,465 IDR.

Optimal Sizing of Energy Storage for Community Microgrids Considering Building Thermal Dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Guodong; Li, Zhi; Starke, Michael R.

This paper proposes an optimization model for the optimal sizing of energy storage in community microgrids considering the building thermal dynamics and customer comfort preference. The proposed model minimizes the annualized cost of the community microgrid, including energy storage investment, purchased energy cost, demand charge, energy storage degradation cost, voluntary load shedding cost and the cost associated with customer discomfort due to room temperature deviation. The decision variables are the power and energy capacity of invested energy storage. In particular, we assume the heating, ventilation and air-conditioning (HVAC) systems can be scheduled intelligently by the microgrid central controller while maintainingmore » the indoor temperature in the comfort range set by customers. For this purpose, the detailed thermal dynamic characteristics of buildings have been integrated into the optimization model. Numerical simulation shows significant cost reduction by the proposed model. The impacts of various costs on the optimal solution are investigated by sensitivity analysis.« less

An Optimization and Assessment on DG adoption in JapanesePrototype Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Nan; Marnay, Chris; Firestone, Ryan

2005-11-30

This research investigates a method of choosing economicallyoptimal DER, expanding on prior studies at the Berkeley Lab using the DERdesign optimization program, the Distributed Energy Resources CustomerAdoption Model (DER-CAM). DER-CAM finds the optimal combination ofinstalled equipment from available DER technologies, given prevailingutility tariffs, site electrical and thermal loads, and a menu ofavailable equipment. It provides a global optimization, albeit idealized,that shows how the site energy load scan be served at minimum cost byselection and operation of on-site generation, heat recovery, andcooling. Five prototype Japanese commercial buildings are examined andDER-CAM applied to select thee conomically optimal DER system for each.The fivemore » building types are office, hospital, hotel, retail, and sportsfacility. Based on the optimization results, energy and emissionreductions are evaluated. Furthermore, a Japan-U.S. comparison study ofpolicy, technology, and utility tariffs relevant to DER installation ispresented. Significant decreases in fuel consumption, carbon emissions,and energy costs were seen in the DER-CAM results. Savings were mostnoticeable in the sports facility, followed by the hospital, hotel, andoffice building.« less

Is Passive or Active House Needed In Face of Global Warming?

NASA Astrophysics Data System (ADS)

Tamosaitis, Romualdas

2017-10-01

The article aims to determine how effective the stricter current requirements for the building envelope insolation are from the economic energy savings perspective. The article deals with a mathematical method for economic assessment of optimal building thermal insulation. The mathematical methods used in this article are based on evaluating the break-even point between the construction expenditures and the economic profit. Recent research shows that energy savings achieved solely through stricter standards applied to the building envelopes are limited in their ability to achieve maximum results. As the ratio of building volume to building envelope increases, further energy saving measures applied to the building envelope produce lower energy saving effects. Energy savings achieved using renewable energy resources, recuperation systems are much more effective. Research shows that much greater effect can be achieved by combining optimal building envelope energy efficiency measures with new requirements related to renewable energy sources and recuperating systems, such as solar batteries, wind turbines or heat pumps.

Premium cost optimization of operational and maintenance of green building in Indonesia using life cycle assessment method

NASA Astrophysics Data System (ADS)

Latief, Yusuf; Berawi, Mohammed Ali; Basten, Van; Budiman, Rachmat; Riswanto

2017-06-01

Building has a big impact on the environmental developments. There are three general motives in building, namely the economy, society, and environment. Total completed building construction in Indonesia increased by 116% during 2009 to 2011. It made the energy consumption increased by 11% within the last three years. In fact, 70% of energy consumption is used for electricity needs on commercial buildings which leads to an increase of greenhouse gas emissions by 25%. Green Building cycle costs is known as highly building upfront cost in Indonesia. The purpose of optimization in this research improves building performance with some of green concept alternatives. Research methodology is mixed method of qualitative and quantitative approaches through questionnaire surveys and case study. Assessing the successful of optimization functions in the existing green building is based on the operational and maintenance phase with the Life Cycle Assessment Method. Choosing optimization results were based on the largest efficiency of building life cycle and the most effective cost to refund.

Energy balance framework for Net Zero Energy buildings

EPA Science Inventory

Approaching a Net Zero Energy (NZE) building goal based on current definitions is flawed for two principal reasons - they only deal with energy quantities required for operations, and they do not establish a threshold, which ensures that buildings are optimized for reduced consum...

Software augmented buildings: Exploiting existing infrastructure to improve energy efficiency and comfort in commercial buildings

NASA Astrophysics Data System (ADS)

Balaji, Bharathan

Commercial buildings consume 19% of energy in the US as of 2010, and traditionally, their energy use has been optimized through improved equipment efficiency and retrofits. Beyond improved hardware and infrastructure, there exists a tremendous potential in reducing energy use through better monitoring and operation. We present several applications that we developed and deployed to support our thesis that building energy use can be reduced through sensing, monitoring and optimization software that modulates use of building subsystems including HVAC. We focus on HVAC systems as these constitute 48-55% of building energy use. Specifically, in case of sensing, we describe an energy apportionment system that enables us to estimate real-time zonal HVAC power consumption by analyzing existing sensor information. With this energy breakdown, we can measure effectiveness of optimization solutions and identify inefficiencies. Central to energy efficiency improvement is determination of human occupancy in buildings. But this information is often unavailable or expensive to obtain using wide scale sensor deployment. We present our system that infers room level occupancy inexpensively by leveraging existing WiFi infrastructure. Occupancy information can be used not only to directly control HVAC but also to infer state of the building for predictive control. Building energy use is strongly influenced by human behaviors, and timely feedback mechanisms can encourage energy saving behavior. Occupants interact with HVAC using thermostats which has shown to be inadequate for thermal comfort. Building managers are responsible for incorporating energy efficiency measures, but our interviews reveal that they struggle to maintain efficiency due to lack of analytical tools and contextual information. We present our software services that provide energy feedback to occupants and building managers, improves comfort with personalized control and identifies energy wasting faults. For wide scale deployment of such energy saving software, they need to be portable across multiple buildings. However, buildings consist of heterogeneous equipment and use inconsistent naming schema, and developers need extensive domain knowledge to map sensor information to a standard format. To enable portability, we present an active learning algorithm that automates mapping building sensor metadata to a standard naming schema.

Assessment of Distributed Generation Potential in JapaneseBuildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Nan; Marnay, Chris; Firestone, Ryan

2005-05-25

To meet growing energy demands, energy efficiency, renewable energy, and on-site generation coupled with effective utilization of exhaust heat will all be required. Additional benefit can be achieved by integrating these distributed technologies into distributed energy resource (DER) systems (or microgrids). This research investigates a method of choosing economically optimal DER, expanding on prior studies at the Berkeley Lab using the DER design optimization program, the Distributed Energy Resources Customer Adoption Model (DER-CAM). DER-CAM finds the optimal combination of installed equipment from available DER technologies, given prevailing utility tariffs, site electrical and thermal loads, and a menu of available equipment.more » It provides a global optimization, albeit idealized, that shows how the site energy loads can be served at minimum cost by selection and operation of on-site generation, heat recovery, and cooling. Five prototype Japanese commercial buildings are examined and DER-CAM applied to select the economically optimal DER system for each. The five building types are office, hospital, hotel, retail, and sports facility. Based on the optimization results, energy and emission reductions are evaluated. Furthermore, a Japan-U.S. comparison study of policy, technology, and utility tariffs relevant to DER installation is presented. Significant decreases in fuel consumption, carbon emissions, and energy costs were seen in the DER-CAM results. Savings were most noticeable in the sports facility (a very favourable CHP site), followed by the hospital, hotel, and office building.« less

Review of optimization techniques of polygeneration systems for building applications

NASA Astrophysics Data System (ADS)

Y, Rong A.; Y, Su; R, Lahdelma

2016-08-01

Polygeneration means simultaneous production of two or more energy products in a single integrated process. Polygeneration is an energy-efficient technology and plays an important role in transition into future low-carbon energy systems. It can find wide applications in utilities, different types of industrial sectors and building sectors. This paper mainly focus on polygeneration applications in building sectors. The scales of polygeneration systems in building sectors range from the micro-level for a single home building to the large- level for residential districts. Also the development of polygeneration microgrid is related to building applications. The paper aims at giving a comprehensive review for optimization techniques for designing, synthesizing and operating different types of polygeneration systems for building applications.

Construction Performance Optimization toward Green Building Premium Cost Based on Greenship Rating Tools Assessment with Value Engineering Method

NASA Astrophysics Data System (ADS)

Latief, Yusuf; Berawi, Mohammed Ali; Basten, Van; Riswanto; Budiman, Rachmat

2017-07-01

Green building concept becomes important in current building life cycle to mitigate environment issues. The purpose of this paper is to optimize building construction performance towards green building premium cost, achieving green building rating tools with optimizing life cycle cost. Therefore, this study helps building stakeholder determining building fixture to achieve green building certification target. Empirically the paper collects data of green building in the Indonesian construction industry such as green building fixture, initial cost, operational and maintenance cost, and certification score achievement. After that, using value engineering method optimized green building fixture based on building function and cost aspects. Findings indicate that construction performance optimization affected green building achievement with increasing energy and water efficiency factors and life cycle cost effectively especially chosen green building fixture.

Passive designs and renewable energy systems optimization of a net zero energy building in Embrun/France

NASA Astrophysics Data System (ADS)

Harkouss, F.; Biwole, P. H.; Fardoun, F.

2018-05-01

Buildings’ optimization is a smart method to inspect the available design choices starting from passive strategies, to energy efficient systems and finally towards the adequate renewable energy system to be implemented. This paper outlines the methodology and the cost-effectiveness potential for optimizing the design of net-zero energy building in a French city; Embrun. The non-dominated sorting genetic algorithm is chosen in order to minimize thermal, electrical demands and life cycle cost while reaching the net zero energy balance; and thus getting the Pareto-front. Elimination and Choice Expressing the Reality decision making method is applied to the Pareto-front so as to obtain one optimal solution. A wide range of energy efficiency measures are investigated, besides solar energy systems are employed to produce required electricity and hot water for domestic purposes. The results indicate that the appropriate selection of the passive parameters is very important and critical in reducing the building energy consumption. The optimum design parameters yield to a decrease of building’s thermal loads and life cycle cost by 32.96% and 14.47% respectively.

Development and Testing of Building Energy Model Using Non-Linear Auto Regression Artificial Neural Networks

NASA Astrophysics Data System (ADS)

Arida, Maya Ahmad

In 1972 sustainable development concept existed and during The years it became one of the most important solution to save natural resources and energy, but now with rising energy costs and increasing awareness of the effect of global warming, the development of building energy saving methods and models become apparently more necessary for sustainable future. According to U.S. Energy Information Administration EIA (EIA), today buildings in the U.S. consume 72 percent of electricity produced, and use 55 percent of U.S. natural gas. Buildings account for about 40 percent of the energy consumed in the United States, more than industry and transportation. Of this energy, heating and cooling systems use about 55 percent. If energy-use trends continue, buildings will become the largest consumer of global energy by 2025. This thesis proposes procedures and analysis techniques for building energy system and optimization methods using time series auto regression artificial neural networks. The model predicts whole building energy consumptions as a function of four input variables, dry bulb and wet bulb outdoor air temperatures, hour of day and type of day. The proposed model and the optimization process are tested using data collected from an existing building located in Greensboro, NC. The testing results show that the model can capture very well the system performance, and The optimization method was also developed to automate the process of finding the best model structure that can produce the best accurate prediction against the actual data. The results show that the developed model can provide results sufficiently accurate for its use in various energy efficiency and saving estimation applications.

A Framework for Daylighting Optimization in Whole Buildings with OpenStudio

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2016-08-12

We present a toolkit and workflow for leveraging the OpenStudio (Guglielmetti et al. 2010) platform to perform daylighting analysis and optimization in a whole building energy modeling (BEM) context. We have re-implemented OpenStudio's integrated Radiance and EnergyPlus functionality as an OpenStudio Measure. The OpenStudio Radiance Measure works within the OpenStudio Application and Parametric Analysis Tool, as well as the OpenStudio Server large scale analysis framework, allowing a rigorous daylighting simulation to be performed on a single building model or potentially an entire population of programmatically generated models. The Radiance simulation results can automatically inform the broader building energy model, andmore » provide dynamic daylight metrics as a basis for decision. Through introduction and example, this paper illustrates the utility of the OpenStudio building energy modeling platform to leverage existing simulation tools for integrated building energy performance simulation, daylighting analysis, and reportage.« less

Technology for Building Systems Integration and Optimization – Landscape Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goetzler, William; Guernsey, Matt; Bargach, Youssef

BTO's Commercial Building Integration (CBI) program helps advance a range of innovative building integration and optimization technologies and solutions, paving the way for high-performing buildings that could use 50-70% less energy than typical buildings. CBI’s work focuses on early stage technology innovation, with an emphasis on how components and systems work together and how whole buildings are integrated and optimized. This landscape study outlines the current body of knowledge, capabilities, and the broader array of solutions supporting integration and optimization in commercial buildings. CBI seeks to support solutions for both existing buildings and new construction, which often present very differentmore » challenges.« less

Energy audit role in building planning

NASA Astrophysics Data System (ADS)

Sipahutar, Riman; Bizzy, Irwin

2017-11-01

An energy audit is one way to overcome the excessive use of energy in buildings. The increasing growth of population, economy, and industry will have an impact on energy demand and the formation of greenhouse gas emissions. Indonesian National Standard (SNI) concerning the building has not been implemented optimally due to the socialization process by a government not yet been conducted. An energy audit of buildings has been carried out at offices and public services. Most electrical energy in buildings used for air refresher equipment or air conditioning. Calculation of OTTV has demonstrated the importance of performing since the beginning of the planning of a building to get energy-efficient buildings.

An Analysis of the DER Adoption Climate in Japan UsingOptimization Results for Prototype Buildings with U.S. Comparisons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Nan; Marnay, Chris; Firestone, Ryan

2006-06-16

This research demonstrates economically optimal distributedenergy resource (DER) system choice using the DER choice and operationsoptimization program, the Distributed Energy Resources Customer AdoptionModel (DER-CAM). DER-CAM finds the optimal combination of installedequipment given prevailing utility tariffs and fuel prices, siteelectrical and thermal loads (including absorption cooling), and a menuof available equipment. It provides a global optimization, albeitidealized, that shows how site useful energy loads can be served atminimum cost. Five prototype Japanese commercial buildings are examinedand DER-CAM is applied to select the economically optimal DER system foreach. Based on the optimization results, energy and emission reductionsare evaluated. Significant decreases in fuelmore » consumption, carbonemissions, and energy costs were seen in the DER-CAM results. Savingswere most noticeable in the prototype sports facility, followed by thehospital, hotel, and office building. Results show that DER with combinedheat and power equipment is a promising efficiency and carbon mitigationstrategy, but that precise system design is necessary. Furthermore, aJapan-U.S. comparison study of policy, technology, and utility tariffsrelevant to DER installation is presented.« less

Effective Energy Simulation and Optimal Design of Side-lit Buildings with Venetian Blinds

NASA Astrophysics Data System (ADS)

Cheng, Tian

Venetian blinds are popularly used in buildings to control the amount of incoming daylight for improving visual comfort and reducing heat gains in air-conditioning systems. Studies have shown that the proper design and operation of window systems could result in significant energy savings in both lighting and cooling. However, there is no convenient computer tool that allows effective and efficient optimization of the envelope of side-lit buildings with blinds now. Three computer tools, Adeline, DOE2 and EnergyPlus widely used for the above-mentioned purpose have been experimentally examined in this study. Results indicate that the two former tools give unacceptable accuracy due to unrealistic assumptions adopted while the last one may generate large errors in certain conditions. Moreover, current computer tools have to conduct hourly energy simulations, which are not necessary for life-cycle energy analysis and optimal design, to provide annual cooling loads. This is not computationally efficient, particularly not suitable for optimal designing a building at initial stage because the impacts of many design variations and optional features have to be evaluated. A methodology is therefore developed for efficient and effective thermal and daylighting simulations and optimal design of buildings with blinds. Based on geometric optics and radiosity method, a mathematical model is developed to reasonably simulate the daylighting behaviors of venetian blinds. Indoor illuminance at any reference point can be directly and efficiently computed. They have been validated with both experiments and simulations with Radiance. Validation results show that indoor illuminances computed by the new models agree well with the measured data, and the accuracy provided by them is equivalent to that of Radiance. The computational efficiency of the new models is much higher than that of Radiance as well as EnergyPlus. Two new methods are developed for the thermal simulation of buildings. A fast Fourier transform (FFT) method is presented to avoid the root-searching process in the inverse Laplace transform of multilayered walls. Generalized explicit FFT formulae for calculating the discrete Fourier transform (DFT) are developed for the first time. They can largely facilitate the implementation of FFT. The new method also provides a basis for generating the symbolic response factors. Validation simulations show that it can generate the response factors as accurate as the analytical solutions. The second method is for direct estimation of annual or seasonal cooling loads without the need for tedious hourly energy simulations. It is validated by hourly simulation results with DOE2. Then symbolic long-term cooling load can be created by combining the two methods with thermal network analysis. The symbolic long-term cooling load can keep the design parameters of interest as symbols, which is particularly useful for the optimal design and sensitivity analysis. The methodology is applied to an office building in Hong Kong for the optimal design of building envelope. Design variables such as window-to-wall ratio, building orientation, and glazing optical and thermal properties are included in the study. Results show that the selected design values could significantly impact the energy performance of windows, and the optimal design of side-lit buildings could greatly enhance energy savings. The application example also demonstrates that the developed methodology significantly facilitates the optimal building design and sensitivity analysis, and leads to high computational efficiency.

Bi-level Optimization Method of Air-conditioning System Based on Office Building Energy Storage Characteristics

NASA Astrophysics Data System (ADS)

Wang, Qingze; Chen, Xingying; Ji, Li; Liao, Yingchen; Yu, Kun

2017-05-01

The air-conditioning system of office building is a large power consumption terminal equipment, whose unreasonable operation mode leads to low energy efficiency. Realizing the optimization of the air-conditioning system has become one of the important research contents of the electric power demand response. In this paper, in order to save electricity cost and improve energy efficiency, bi-level optimization method of air-conditioning system based on TOU price is put forward by using the energy storage characteristics of the office building itself. In the upper level, the operation mode of the air-conditioning system is optimized in order to minimize the uses’ electricity cost in the premise of ensuring user’ comfort according to the information of outdoor temperature and TOU price, and the cooling load of the air-conditioning is output to the lower level; In the lower level, the distribution mode of cooling load among the multi chillers is optimized in order to maximize the energy efficiency according to the characteristics of each chiller. Finally, the experimental results under different modes demonstrate that the strategy can improve the energy efficiency of chillers and save the electricity cost for users.

The potential for distributed generation in Japanese prototype buildings: A DER-CAM analysis of policy, tariff design, building energy use, and technology development (English Version)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Nan; Marnay, Chris; Firestone, Ryan

The August 2003 blackout of the northeastern U.S. and CANADA caused great economic losses and inconvenience to New York City and other affected areas. The blackout was a warning to the rest of the world that the ability of conventional power systems to meet growing electricity demand is questionable. Failure of large power systems can lead to serious emergencies. Introduction of on-site generation, renewable energy such as solar and wind power and the effective utilization of exhaust heat is needed, to meet the growing energy demands of the residential and commercial sectors. Additional benefit can be achieved by integrating thesemore » distributed technologies into distributed energy resource (DER) systems. This work demonstrates a method for choosing and designing economically optimal DER systems. An additional purpose of this research is to establish a database of energy tariffs, DER technology cost and performance characteristics, and building energy consumption for Japan. This research builds on prior DER studies at the Ernest Orlando Lawrence Berkeley National Laboratory (LBNL) and with their associates in the Consortium for Electric Reliability Technology Solutions (CERTS) and operation, including the development of the microgrid concept, and the DER selection optimization program, the Distributed Energy Resources Customer Adoption Model (DER-CAM). DER-CAM is a tool designed to find the optimal combination of installed equipment and an idealized operating schedule to minimize a site's energy bills, given performance and cost data on available DER technologies, utility tariffs, and site electrical and thermal loads over a test period, usually an historic year. Since hourly electric and thermal energy data are rarely available, they are typically developed by building simulation for each of six end use loads used to model the building: electric-only loads, space heating, space cooling, refrigeration, water heating, and natural-gas-only loads. DER-CAM provides a global optimization, albeit idealized, that shows how the necessary useful energy loads can be provided for at minimum cost by selection and operation of on-site generation, heat recovery, cooling, and efficiency improvements. This study examines five prototype commercial buildings and uses DER-CAM to select the economically optimal DER system for each. The five building types are office, hospital, hotel, retail, and sports facility. Each building type was considered for both 5,000 and 10,000 square meter floor sizes. The energy consumption of these building types is based on building energy simulation and published literature. Based on the optimization results, energy conservation and the emissions reduction were also evaluated. Furthermore, a comparison study between Japan and the U.S. has been conducted covering the policy, technology and the utility tariffs effects on DER systems installations. This study begins with an examination of existing DER research. Building energy loads were then generated through simulation (DOE-2) and scaled to match available load data in the literature. Energy tariffs in Japan and the U.S. were then compared: electricity prices did not differ significantly, while commercial gas prices in Japan are much higher than in the U.S. For smaller DER systems, the installation costs in Japan are more than twice those in the U.S., but this difference becomes smaller with larger systems. In Japan, DER systems are eligible for a 1/3 rebate of installation costs, while subsidies in the U.S. vary significantly by region and application. For 10,000 m{sup 2} buildings, significant decreases in fuel consumption, carbon emissions, and energy costs were seen in the economically optimal results. This was most noticeable in the sports facility, followed the hospital and hotel. This research demonstrates that office buildings can benefit from CHP, in contrast to popular opinion. For hospitals and sports facilities, the use of waste heat is particularly effective for water and space heating. For the other building types, waste heat is most effectively used for both heating and cooling. The same examination was done for the 5,000 m{sup 2} buildings. Although CHP installation capacity is smaller and the payback periods are longer, economic, fuel efficiency, and environmental benefits are still seen. While these benefits remain even when subsidies are removed, the increased installation costs lead to lower levels of installation capacity and thus benefit.« less

Global optimization framework for solar building design

NASA Astrophysics Data System (ADS)

Silva, N.; Alves, N.; Pascoal-Faria, P.

2017-07-01

The generative modeling paradigm is a shift from static models to flexible models. It describes a modeling process using functions, methods and operators. The result is an algorithmic description of the construction process. Each evaluation of such an algorithm creates a model instance, which depends on its input parameters (width, height, volume, roof angle, orientation, location). These values are normally chosen according to aesthetic aspects and style. In this study, the model's parameters are automatically generated according to an objective function. A generative model can be optimized according to its parameters, in this way, the best solution for a constrained problem is determined. Besides the establishment of an overall framework design, this work consists on the identification of different building shapes and their main parameters, the creation of an algorithmic description for these main shapes and the formulation of the objective function, respecting a building's energy consumption (solar energy, heating and insulation). Additionally, the conception of an optimization pipeline, combining an energy calculation tool with a geometric scripting engine is presented. The methods developed leads to an automated and optimized 3D shape generation for the projected building (based on the desired conditions and according to specific constrains). The approach proposed will help in the construction of real buildings that account for less energy consumption and for a more sustainable world.

Predictive Optimal Control of Active and Passive Building Thermal Storage Inventory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gregor P. Henze; Moncef Krarti

2005-09-30

Cooling of commercial buildings contributes significantly to the peak demand placed on an electrical utility grid. Time-of-use electricity rates encourage shifting of electrical loads to off-peak periods at night and weekends. Buildings can respond to these pricing signals by shifting cooling-related thermal loads either by precooling the building's massive structure or the use of active thermal energy storage systems such as ice storage. While these two thermal batteries have been engaged separately in the past, this project investigated the merits of harnessing both storage media concurrently in the context of predictive optimal control. To pursue the analysis, modeling, and simulationmore » research of Phase 1, two separate simulation environments were developed. Based on the new dynamic building simulation program EnergyPlus, a utility rate module, two thermal energy storage models were added. Also, a sequential optimization approach to the cost minimization problem using direct search, gradient-based, and dynamic programming methods was incorporated. The objective function was the total utility bill including the cost of reheat and a time-of-use electricity rate either with or without demand charges. An alternative simulation environment based on TRNSYS and Matlab was developed to allow for comparison and cross-validation with EnergyPlus. The initial evaluation of the theoretical potential of the combined optimal control assumed perfect weather prediction and match between the building model and the actual building counterpart. The analysis showed that the combined utilization leads to cost savings that is significantly greater than either storage but less than the sum of the individual savings. The findings reveal that the cooling-related on-peak electrical demand of commercial buildings can be considerably reduced. A subsequent analysis of the impact of forecasting uncertainty in the required short-term weather forecasts determined that it takes only very simple short-term prediction models to realize almost all of the theoretical potential of this control strategy. Further work evaluated the impact of modeling accuracy on the model-based closed-loop predictive optimal controller to minimize utility cost. The following guidelines have been derived: For an internal heat gain dominated commercial building, reasonable geometry simplifications are acceptable without a loss of cost savings potential. In fact, zoning simplification may improve optimizer performance and save computation time. The mass of the internal structure did not show a strong effect on the optimization. Building construction characteristics were found to impact building passive thermal storage capacity. It is thus advisable to make sure the construction material is well modeled. Zone temperature setpoint profiles and TES performance are strongly affected by mismatches in internal heat gains, especially when they are underestimated. Since they are a key factor in determining the building cooling load, efforts should be made to keep the internal gain mismatch as small as possible. Efficiencies of the building energy systems affect both zone temperature setpoints and active TES operation because of the coupling of the base chiller for building precooling and the icemaking TES chiller. Relative efficiencies of the base and TES chillers will determine the balance of operation of the two chillers. The impact of mismatch in this category may be significant. Next, a parametric analysis was conducted to assess the effects of building mass, utility rate, building location and season, thermal comfort, central plant capacities, and an economizer on the cost saving performance of optimal control for active and passive building thermal storage inventory. The key findings are: (1) Heavy-mass buildings, strong-incentive time-of-use electrical utility rates, and large on-peak cooling loads will likely lead to attractive savings resulting from optimal combined thermal storage control. (2) By using economizer to take advantage of the cool fresh air during the night, the building electrical cost can be reduced by using less mechanical cooling. (3) Larger base chiller and active thermal storage capacities have the potential of shifting more cooling loads to off-peak hours and thus higher savings can be achieved. (4) Optimal combined thermal storage control with a thermal comfort penalty included in the objective function can improve the thermal comfort levels of building occupants when compared to the non-optimized base case. Lab testing conducted in the Larson HVAC Laboratory during Phase 2 showed that the EnergyPlus-based simulation was a surprisingly accurate prediction of the experiment. Therefore, actual savings of building energy costs can be expected by applying optimal controls from simulation results.« less

Improving energy sustainability for public buildings in Italian mountain communities.

PubMed

Mutani, Guglielmina; Cornaglia, Mauro; Berto, Massimo

2018-05-01

The objective of this work is to analyze and then optimize thermal energy consumptions of public buildings located within the mountain community of Lanzo, Ceronda and Casternone Valleys. Some measures have been proposed to reduce energy consumption and consequently the economic cost for energy production, as well as the harmful GHG emissions in the atmosphere. Initially, a study of the mountain territory has been carried out, because of its vast extension and climatic differences. Defined the communities and the buildings under investigation, energy dependant data were collected for the analysis of energy consumption monitoring: consumption data of three heating seasons, geometric buildings characteristics, type of opaque and transparent envelope, heating systems information with boiler performance and climatic data. Afterward, five buildings with critical energy performances were selected; for each of these buildings, different retrofit interventions have been hypothesized to reduce the energy consumption, with thermal insulation of vertical or horizontal structures, new windows or boiler substitution. The cost-optimal technique was used to choose the interventions that offered higher energy performance at lower costs; then a retrofit scenario has been planned with a specific financial investment. Finally, results showed possible future developments and scenarios related to buildings energy efficiency with regard to the topic of biomass exploitation and its local availability in this area. In this context, the biomass energy resource could to create a virtuous environmental, economic and social process, favouring also local development.

Design and Optimization of Slot Aluminum Alloy Connectors of Photovoltaics Applied to High-rise Building Facades

NASA Astrophysics Data System (ADS)

Liang, Ya-Wei; Zhang, Hong-Mei; Dong, Jin-Zhi; Shi, Zhen-Hua

2016-05-01

Building Integrated Photovoltaic (BIPV) is a resort to save energy and reduce heat gain of buildings, utilize new and renewable energy, solve environment problems and alleviate electricity shortage in large cities. The area needed to generate power makes facade integrated photovoltaic panel a superb choice, especially in high-rise buildings. Numerous scholars have hitherto explored Building Facade Integrated Photovoltaic, however, focusing mainly on thermal performance, which fails to ensure seismic safety of high-rise buildings integrated photovoltaic. Based on connecting forms of the glass curtain wall, a connector jointing photovoltaic panel and facade was designed, which underwent loading position and size optimization. Static loading scenarios were conducted to test and verify the connector's mechanical properties under gravity and wind loading by means of HyperWorks. Compared to the unoptimized design, the optimized one saved material and managed to reduce maximum deflection by 74.64%.

Cybersecurity and Optimization in Smart “Autonomous” Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mylrea, Michael E.; Gourisetti, Sri Nikhil Gup

Significant resources have been invested in making buildings “smart” by digitizing, networking and automating key systems and operations. Smart autonomous buildings create new energy efficiency, economic and environmental opportunities. But as buildings become increasingly networked to the Internet, they can also become more vulnerable to various cyber threats. Automated and Internet-connected buildings systems, equipment, controls, and sensors can significantly increase cyber and physical vulnerabilities that threaten the confidentiality, integrity, and availability of critical systems in organizations. Securing smart autonomous buildings presents a national security and economic challenge to the nation. Ignoring this challenge threatens business continuity and the availability ofmore » critical infrastructures that are enabled by smart buildings. In this chapter, the authors address challenges and explore new opportunities in securing smart buildings that are enhanced by machine learning, cognitive sensing, artificial intelligence (AI) and smart-energy technologies. The chapter begins by identifying cyber-threats and challenges to smart autonomous buildings. Then it provides recommendations on how AI enabled solutions can help smart buildings and facilities better protect, detect and respond to cyber-physical threats and vulnerabilities. Next, the chapter will provide case studies that examine how combining AI with innovative smart-energy technologies can increase both cybersecurity and energy efficiency savings in buildings. The chapter will conclude by proposing recommendations for future cybersecurity and energy optimization research for examining AI enabled smart-energy technology.« less

Application of the Software as a Service Model to the Control of Complex Building Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stadler, Michael; Donadee, Jonathan; Marnay, Chris

2011-03-17

In an effort to create broad access to its optimization software, Lawrence Berkeley National Laboratory (LBNL), in collaboration with the University of California at Davis (UC Davis) and OSISoft, has recently developed a Software as a Service (SaaS) Model for reducing energy costs, cutting peak power demand, and reducing carbon emissions for multipurpose buildings. UC Davis currently collects and stores energy usage data from buildings on its campus. Researchers at LBNL sought to demonstrate that a SaaS application architecture could be built on top of this data system to optimize the scheduling of electricity and heat delivery in the building.more » The SaaS interface, known as WebOpt, consists of two major parts: a) the investment& planning and b) the operations module, which builds on the investment& planning module. The operational scheduling and load shifting optimization models within the operations module use data from load prediction and electrical grid emissions models to create an optimal operating schedule for the next week, reducing peak electricity consumption while maintaining quality of energy services. LBNL's application also provides facility managers with suggested energy infrastructure investments for achieving their energy cost and emission goals based on historical data collected with OSISoft's system. This paper describes these models as well as the SaaS architecture employed by LBNL researchers to provide asset scheduling services to UC Davis. The peak demand, emissions, and cost implications of the asset operation schedule and investments suggested by this optimization model are analysed.« less

Application of the Software as a Service Model to the Control of Complex Building Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stadler, Michael; Donadee, Jon; Marnay, Chris

2011-03-18

In an effort to create broad access to its optimization software, Lawrence Berkeley National Laboratory (LBNL), in collaboration with the University of California at Davis (UC Davis) and OSISoft, has recently developed a Software as a Service (SaaS) Model for reducing energy costs, cutting peak power demand, and reducing carbon emissions for multipurpose buildings. UC Davis currently collects and stores energy usage data from buildings on its campus. Researchers at LBNL sought to demonstrate that a SaaS application architecture could be built on top of this data system to optimize the scheduling of electricity and heat delivery in the building.more » The SaaS interface, known as WebOpt, consists of two major parts: a) the investment& planning and b) the operations module, which builds on the investment& planning module. The operational scheduling and load shifting optimization models within the operations module use data from load prediction and electrical grid emissions models to create an optimal operating schedule for the next week, reducing peak electricity consumption while maintaining quality of energy services. LBNL's application also provides facility managers with suggested energy infrastructure investments for achieving their energy cost and emission goals based on historical data collected with OSISoft's system. This paper describes these models as well as the SaaS architecture employed by LBNL researchers to provide asset scheduling services to UC Davis. The peak demand, emissions, and cost implications of the asset operation schedule and investments suggested by this optimization model are analyzed.« less

Auto-DR and Pre-cooling of Buildings at Tri-City Corporate Center

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yin, Rongxin; Xu, Peng; Kiliccote, Sila

2008-11-01

Over the several past years, Lawrence Berkeley National Laboratory (LBNL) has conducted field tests for different pre-cooling strategies in different commercial buildings within California. The test results indicated that pre-cooling strategies were effective in reducing electric demand in these buildings during peak periods. This project studied how to optimize pre-cooling strategies for eleven buildings in the Tri-City Corporate Center, San Bernardino, California with the assistance of a building energy simulation tool -- the Demand Response Quick Assessment Tool (DRQAT) developed by LBNL's Demand Response Research Center funded by the California Energy Commission's Public Interest Energy Research (PIER) Program. From themore » simulation results of these eleven buildings, optimal pre-cooling and temperature reset strategies were developed. The study shows that after refining and calibrating initial models with measured data, the accuracy of the models can be greatly improved and the models can be used to predict load reductions for automated demand response (Auto-DR) events. This study summarizes the optimization experience of the procedure to develop and calibrate building models in DRQAT. In order to confirm the actual effect of demand response strategies, the simulation results were compared to the field test data. The results indicated that the optimal demand response strategies worked well for all buildings in the Tri-City Corporate Center. This study also compares DRQAT with other building energy simulation tools (eQUEST and BEST). The comparison indicate that eQUEST and BEST underestimate the actual demand shed of the pre-cooling strategies due to a flaw in DOE2's simulation engine for treating wall thermal mass. DRQAT is a more accurate tool in predicting thermal mass effects of DR events.« less

Zero Energy Schools: Designing for the Future: Zero Energy Ready K-12 Schools

DOE Office of Scientific and Technical Information (OSTI.GOV)

Torcellini, Paul A

Designing, building, and operating zero energy ready K-12 schools provides benefits for districts, students, and teachers. Optimizing energy efficiency is important in any building, but it's particularly important in K-12 schools. Many U.S. school districts struggle for funding, and improving a school building's energy efficiency can free up operational funds that may then be available for educational and other purposes.

Net-zero Building Cluster Simulations and On-line Energy Forecasting for Adaptive and Real-Time Control and Decisions

NASA Astrophysics Data System (ADS)

Li, Xiwang

Buildings consume about 41.1% of primary energy and 74% of the electricity in the U.S. Moreover, it is estimated by the National Energy Technology Laboratory that more than 1/4 of the 713 GW of U.S. electricity demand in 2010 could be dispatchable if only buildings could respond to that dispatch through advanced building energy control and operation strategies and smart grid infrastructure. In this study, it is envisioned that neighboring buildings will have the tendency to form a cluster, an open cyber-physical system to exploit the economic opportunities provided by a smart grid, distributed power generation, and storage devices. Through optimized demand management, these building clusters will then reduce overall primary energy consumption and peak time electricity consumption, and be more resilient to power disruptions. Therefore, this project seeks to develop a Net-zero building cluster simulation testbed and high fidelity energy forecasting models for adaptive and real-time control and decision making strategy development that can be used in a Net-zero building cluster. The following research activities are summarized in this thesis: 1) Development of a building cluster emulator for building cluster control and operation strategy assessment. 2) Development of a novel building energy forecasting methodology using active system identification and data fusion techniques. In this methodology, a systematic approach for building energy system characteristic evaluation, system excitation and model adaptation is included. The developed methodology is compared with other literature-reported building energy forecasting methods; 3) Development of the high fidelity on-line building cluster energy forecasting models, which includes energy forecasting models for buildings, PV panels, batteries and ice tank thermal storage systems 4) Small scale real building validation study to verify the performance of the developed building energy forecasting methodology. The outcomes of this thesis can be used for building cluster energy forecasting model development and model based control and operation optimization. The thesis concludes with a summary of the key outcomes of this research, as well as a list of recommendations for future work.

Evaluation of Building Energy Saving Through the Development of Venetian Blinds' Optimal Control Algorithm According to the Orientation and Window-to-Wall Ratio

NASA Astrophysics Data System (ADS)

Kwon, Hyuk Ju; Yeon, Sang Hun; Lee, Keum Ho; Lee, Kwang Ho

2018-02-01

As various studies focusing on building energy saving have been continuously conducted, studies utilizing renewable energy sources, instead of fossil fuel, are needed. In particular, studies regarding solar energy are being carried out in the field of building science; in order to utilize such solar energy effectively, solar radiation being brought into the indoors should be acquired and blocked properly. Blinds are a typical solar radiation control device that is capable of controlling indoor thermal and light environments. However, slat-type blinds are manually controlled, giving a negative effect on building energy saving. In this regard, studies regarding the automatic control of slat-type blinds have been carried out for the last couple of decades. Therefore, this study aims to provide preliminary data for optimal control research through the controlling of slat angle in slat-type blinds by comprehensively considering various input variables. The window area ratio and orientation were selected as input variables. It was found that an optimal control algorithm was different among each window-to-wall ratio and window orientation. In addition, through comparing and analyzing the building energy saving performance for each condition by applying the developed algorithms to simulations, up to 20.7 % energy saving was shown in the cooling period and up to 12.3 % energy saving was shown in the heating period. In addition, building energy saving effect was greater as the window area ratio increased given the same orientation, and the effects of window-to-wall ratio in the cooling period were higher than those of window-to-wall ratio in the heating period.

Optimal Coordination of Building Loads and Energy Storage for Power Grid and End User Services

DOE PAGES

Hao, He; Wu, Di; Lian, Jianming; ...

2017-01-18

Demand response and energy storage play a profound role in the smart grid. The focus of this study is to evaluate benefits of coordinating flexible loads and energy storage to provide power grid and end user services. We present a Generalized Battery Model (GBM) to describe the flexibility of building loads and energy storage. An optimization-based approach is proposed to characterize the parameters (power and energy limits) of the GBM for flexible building loads. We then develop optimal coordination algorithms to provide power grid and end user services such as energy arbitrage, frequency regulation, spinning reserve, as well as energymore » cost and demand charge reduction. Several case studies have been performed to demonstrate the efficacy of the GBM and coordination algorithms, and evaluate the benefits of using their flexibility for power grid and end user services. We show that optimal coordination yields significant cost savings and revenue. Moreover, the best option for power grid services is to provide energy arbitrage and frequency regulation. Finally and furthermore, when coordinating flexible loads with energy storage to provide end user services, it is recommended to consider demand charge in addition to time-of-use price in order to flatten the aggregate power profile.« less

Optimized design and control of an off grid solar PV/hydrogen fuel cell power system for green buildings

NASA Astrophysics Data System (ADS)

Ghenai, C.; Bettayeb, M.

2017-11-01

Modelling, simulation, optimization and control strategies are used in this study to design a stand-alone solar PV/Fuel Cell/Battery/Generator hybrid power system to serve the electrical load of a commercial building. The main objective is to design an off grid energy system to meet the desired electric load of the commercial building with high renewable fraction, low emissions and low cost of energy. The goal is to manage the energy consumption of the building, reduce the associate cost and to switch from grid-tied fossil fuel power system to an off grid renewable and cleaner power system. Energy audit was performed in this study to determine the energy consumption of the building. Hourly simulations, modelling and optimization were performed to determine the performance and cost of the hybrid power configurations using different control strategies. The results show that the hybrid off grid solar PV/Fuel Cell/Generator/Battery/Inverter power system offers the best performance for the tested system architectures. From the total energy generated from the off grid hybrid power system, 73% is produced from the solar PV, 24% from the fuel cell and 3% from the backup Diesel generator. The produced power is used to meet all the AC load of the building without power shortage (<0.1%). The hybrid power system produces 18.2% excess power that can be used to serve the thermal load of the building. The proposed hybrid power system is sustainable, economically viable and environmentally friendly: High renewable fraction (66.1%), low levelized cost of energy (92 /MWh), and low carbon dioxide emissions (24 kg CO2/MWh) are achieved.

Energy and Process Assessment Protocol for Industrial Buildings

DTIC Science & Technology

2007-05-01

address production and maintenance needs at U.S. Army Arsenals and Depots. The Protocol is partly the result of an international collaboration under...the International Energy Agency “Energy Conservation in Buildings and Community Systems” Annex 46, Subtask A. A group of government, institutional...Optimization Technology.” This is also a part of the IEA-ECBCS ( International Energy Agency – En- ergy Conservation in Buildings and Community Systems

Danny Studer | NREL

Science.gov Websites

Daniel.Studer@nrel.gov | 303-275-4368 Daniel joined NREL in 2009. As a member of the Commercial Buildings using EnergyPlus to identify large-scale areas for reducing and optimizing commercial building energy consumption. Recently, Daniel led NREL's commercial building workforce development efforts and he is leading

High performance solutions and data for nZEBs offices located in warm climates.

PubMed

Congedo, Paolo Maria; Baglivo, Cristina; Zacà, Ilaria; D Agostino, Delia

2015-12-01

This data article contains eleven tables supporting the research article entitled: Cost-Optimal Design For Nearly Zero Energy Office Buildings Located In Warm Climates [1]. The data explain the procedure of minimum energy performance requirements presented by the European Directive (EPBD) [2] to establish several variants of energy efficiency measures with the integration of renewable energy sources in order to reach nZEBs (nearly zero energy buildings) by 2020. This files include the application of comparative methodological framework and give the cost-optimal solutions for non-residential building located in Southern Italy. The data describe office sector in which direct the current European policies and investments [3], [4]. In particular, the localization of the building, geometrical features, thermal properties of the envelope and technical systems for HVAC are reported in the first sections. Energy efficiency measures related to orientation, walls, windows, heating, cooling, dhw and RES are given in the second part of the group; this data article provides 256 combinations for a financial and macroeconomic analysis.

Practical Study on HVAC Control Technology Based on the Learning Function and Optimum Multiple Objective Processes

NASA Astrophysics Data System (ADS)

Ueda, Haruka; Dazai, Ryota; Kaseda, Chosei; Ikaga, Toshiharu; Kato, Akihiro

Demand among large office buildings for the energy-saving benefits of the HVAC (Heating, Ventilating and Air-Conditioning) System are increasing as more and more people become concerned with global environmental issues. However, immoderate measures taken in the interest of energy conservation may encroach on the thermal comfort and productivity level of office workers. Building management should satisfy both indoor thermal comfort and energy conservation while adapting to the many regulatory, social, climate, and other changes that occur during the lifespan of the building. This paper demonstrates how optimal control of the HVAC system, based on data modeling and the multi-objective optimal method, achieves an efficient equilibrium between thermal comfort and energy conservation.

Optimization of design parameters of low-energy buildings

NASA Astrophysics Data System (ADS)

Vala, Jiří; Jarošová, Petra

2017-07-01

Evaluation of temperature development and related consumption of energy required for heating, air-conditioning, etc. in low-energy buildings requires the proper physical analysis, covering heat conduction, convection and radiation, including beam and diffusive components of solar radiation, on all building parts and interfaces. The system approach and the Fourier multiplicative decomposition together with the finite element technique offers the possibility of inexpensive and robust numerical and computational analysis of corresponding direct problems, as well as of the optimization ones with several design variables, using the Nelder-Mead simplex method. The practical example demonstrates the correlation between such numerical simulations and the time series of measurements of energy consumption on a small family house in Ostrov u Macochy (35 km northern from Brno).

BEopt-CA (Ex) -- A Tool for Optimal Integration of EE/DR/ES+PV in Existing California Homes. Cooperative Research and Development Final Report, CRADA Number CRD-11-429

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christensen, Craig

Opportunities for combining energy efficiency, demand response, and energy storage with PV are often missed, because the required knowledge and expertise for these different technologies exist in separate organizations or individuals. Furthermore, there is a lack of quantitative tools to optimize energy efficiency, demand response and energy storage with PV, especially for existing buildings. Our goal is to develop a modeling tool, BEopt-CA (Ex), with capabilities to facilitate identification and implementation of a balanced integration of energy efficiency (EE), demand response (DR), and energy storage (ES) with photovoltaics (PV) within the residential retrofit market. To achieve this goal, we willmore » adapt and extend an existing tool -- BEopt -- that is designed to identify optimal combinations of efficiency and PV in new home designs. In addition, we will develop multifamily residential modeling capabilities for use in California, to facilitate integration of distributed solar power into the grid in order to maximize its value to California ratepayers. The project is follow-on research that leverages previous California Solar Initiative RD&D investment in the BEopt software. BEopt facilitates finding the least cost combination of energy efficiency and renewables to support integrated DSM (iDSM) and Zero Net Energy (ZNE) in California residential buildings. However, BEopt is currently focused on modeling single-family houses and does not include satisfactory capabilities for modeling multifamily homes. The project brings BEopt's existing modeling and optimization capabilities to multifamily buildings, including duplexes, triplexes, townhouses, flats, and low-rise apartment buildings.« less

Evaluation of green building rating tools based on existing green building achievement in Indonesia using Life Cycle Assessment Method

NASA Astrophysics Data System (ADS)

Basten, Van; Latief, Yusuf; Berawi, Mohammed Ali; Budiman, Rachmat; Riswanto

2017-03-01

Total completed building construction value in Indonesia increased 116% during 2009 to 2011. That's followed by increasing 11% energy consumption in Indonesia in the last three years with 70% energy met to the electricity needs of commercial building. In addition, a few application of green building concept in Indonesia made the greenhouse gas emissions or CO2 amount increased by 25%. Construction, operation, and maintain of building cost consider relatively high. The evaluation in this research is used to improve the building performance with some of green concept alternatives. The research methodology is conducted by combination of qualitative and quantitative approaches through interview and case study. Assessing the successful of optimization functions in the existing green building is based on the operational and maintenance phase with the Life Cycle Assessment (LCA) Method. The result of optimization that is the largest efficiency and effective of building life cycle.

The use of least squares methods in functional optimization of energy use prediction models

NASA Astrophysics Data System (ADS)

Bourisli, Raed I.; Al-Shammeri, Basma S.; AlAnzi, Adnan A.

2012-06-01

The least squares method (LSM) is used to optimize the coefficients of a closed-form correlation that predicts the annual energy use of buildings based on key envelope design and thermal parameters. Specifically, annual energy use is related to a number parameters like the overall heat transfer coefficients of the wall, roof and glazing, glazing percentage, and building surface area. The building used as a case study is a previously energy-audited mosque in a suburb of Kuwait City, Kuwait. Energy audit results are used to fine-tune the base case mosque model in the VisualDOE{trade mark, serif} software. Subsequently, 1625 different cases of mosques with varying parameters were developed and simulated in order to provide the training data sets for the LSM optimizer. Coefficients of the proposed correlation are then optimized using multivariate least squares analysis. The objective is to minimize the difference between the correlation-predicted results and the VisualDOE-simulation results. It was found that the resulting correlation is able to come up with coefficients for the proposed correlation that reduce the difference between the simulated and predicted results to about 0.81%. In terms of the effects of the various parameters, the newly-defined weighted surface area parameter was found to have the greatest effect on the normalized annual energy use. Insulating the roofs and walls also had a major effect on the building energy use. The proposed correlation and methodology can be used during preliminary design stages to inexpensively assess the impacts of various design variables on the expected energy use. On the other hand, the method can also be used by municipality officials and planners as a tool for recommending energy conservation measures and fine-tuning energy codes.

Use of Binary Partition Tree and energy minimization for object-based classification of urban land cover

NASA Astrophysics Data System (ADS)

Li, Mengmeng; Bijker, Wietske; Stein, Alfred

2015-04-01

Two main challenges are faced when classifying urban land cover from very high resolution satellite images: obtaining an optimal image segmentation and distinguishing buildings from other man-made objects. For optimal segmentation, this work proposes a hierarchical representation of an image by means of a Binary Partition Tree (BPT) and an unsupervised evaluation of image segmentations by energy minimization. For building extraction, we apply fuzzy sets to create a fuzzy landscape of shadows which in turn involves a two-step procedure. The first step is a preliminarily image classification at a fine segmentation level to generate vegetation and shadow information. The second step models the directional relationship between building and shadow objects to extract building information at the optimal segmentation level. We conducted the experiments on two datasets of Pléiades images from Wuhan City, China. To demonstrate its performance, the proposed classification is compared at the optimal segmentation level with Maximum Likelihood Classification and Support Vector Machine classification. The results show that the proposed classification produced the highest overall accuracies and kappa coefficients, and the smallest over-classification and under-classification geometric errors. We conclude first that integrating BPT with energy minimization offers an effective means for image segmentation. Second, we conclude that the directional relationship between building and shadow objects represented by a fuzzy landscape is important for building extraction.

Energy Conservation: Heating Navy Hangars

DTIC Science & Technology

1984-07-01

temperature, IF Tf Inside air temperature 1 foot above the floor, OF T. Inside design temperature, IF To Hot water temperature setpoint , OF TON Chiller ...systems capable of optimizing energy usage base-wide. An add-on to an existing large scale EMCS is probably the first preference, followed by single...the building comfort conditions are met during hours of building occupancy. 2. Optimized Start/Stop turns on equipment at the latest possible time and

Dylan Cutler | NREL

Science.gov Websites

focuses on integration and optimization of distributed energy resources, specifically cost-optimal sizing Campus team which is focusing on NREL's own control system integration and energy informatics sizing and dispatch of distributed energy resources Integration of building and utility control systems

A New Distributed Optimization for Community Microgrids Scheduling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Starke, Michael R; Tomsovic, Kevin

This paper proposes a distributed optimization model for community microgrids considering the building thermal dynamics and customer comfort preference. The microgrid central controller (MCC) minimizes the total cost of operating the community microgrid, including fuel cost, purchasing cost, battery degradation cost and voluntary load shedding cost based on the customers' consumption, while the building energy management systems (BEMS) minimize their electricity bills as well as the cost associated with customer discomfort due to room temperature deviation from the set point. The BEMSs and the MCC exchange information on energy consumption and prices. When the optimization converges, the distributed generation scheduling,more » energy storage charging/discharging and customers' consumption as well as the energy prices are determined. In particular, we integrate the detailed thermal dynamic characteristics of buildings into the proposed model. The heating, ventilation and air-conditioning (HVAC) systems can be scheduled intelligently to reduce the electricity cost while maintaining the indoor temperature in the comfort range set by customers. Numerical simulation results show the effectiveness of proposed model.« less

ACMV Energy Analysis for Academic Building: A Case Study

NASA Astrophysics Data System (ADS)

Hywel, R.; Tee, B. T.; Arifin, M. Y.; Tan, C. F.; Gan, C. K.; Chong, CT

2015-09-01

Building energy audit examines the ways actual energy consumption is currently used in the facility, in the case of a completed and occupied building and identifies some alternatives to reduce current energy usage. Implementation of energy audit are practically used to analyze energy consumption pattern, monitoring on how the energy used varies with time in the building, how the system element interrelate, and study the effect of external environment towards building. In this case study, a preliminary energy audit is focusing on Air-Conditioning & Mechanical Ventilation (ACMV) system which reportedly consumed 40% of the total energy consumption in typical building. It is also the main system that provides comfortable and healthy environment for the occupants. The main purpose of this study is to evaluate the current ACMV system performance, energy optimization and identifying the energy waste on UTeM's academic building. To attain this, the preliminary data is collected and then analyzed. Based on the data, economic analysis will be determined before cost-saving methods are being proposed.

Hierarchical fuzzy control of low-energy building systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Zhen; Dexter, Arthur

2010-04-15

A hierarchical fuzzy supervisory controller is described that is capable of optimizing the operation of a low-energy building, which uses solar energy to heat and cool its interior spaces. The highest level fuzzy rules choose the most appropriate set of lower level rules according to the weather and occupancy information; the second level fuzzy rules determine an optimal energy profile and the overall modes of operation of the heating, ventilating and air-conditioning system (HVAC); the third level fuzzy rules select the mode of operation of specific equipment, and assign schedules to the local controllers so that the optimal energy profilemore » can be achieved in the most efficient way. Computer simulation is used to compare the hierarchical fuzzy control scheme with a supervisory control scheme based on expert rules. The performance is evaluated by comparing the energy consumption and thermal comfort. (author)« less

Modeling and Optimization of Commercial Buildings and Stationary Fuel Cell Systems (Presentation)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ainscough, C.; McLarty, D.; Sullivan, R.

2013-10-01

This presentation describes the Distributed Generation Building Energy Assessment Tool (DG-BEAT) developed by the National Renewable Energy Laboratory and the University of California Irvine. DG-BEAT is designed to allow stakeholders to assess the economics of installing stationary fuel cell systems in a variety of building types in the United States.

A techno-economic assessment of grid connected photovoltaic system for hospital building in Malaysia

NASA Astrophysics Data System (ADS)

Mat Isa, Normazlina; Tan, Chee Wei; Yatim, AHM

2017-07-01

Conventionally, electricity in hospital building are supplied by the utility grid which uses mix fuel including coal and gas. Due to enhancement in renewable technology, many building shall moving forward to install their own PV panel along with the grid to employ the advantages of the renewable energy. This paper present an analysis of grid connected photovoltaic (GCPV) system for hospital building in Malaysia. A discussion is emphasized on the economic analysis based on Levelized Cost of Energy (LCOE) and total Net Present Post (TNPC) in regards with the annual interest rate. The analysis is performed using Hybrid Optimization Model for Electric Renewables (HOMER) software which give optimization and sensitivity analysis result. An optimization result followed by the sensitivity analysis also being discuss in this article thus the impact of the grid connected PV system has be evaluated. In addition, the benefit from Net Metering (NeM) mechanism also discussed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aldrich, Robb; Butterfield, Karla

With funding from the Building America Program, part of the U.S. Department of Energy Building Technologies Office, the Consortium for Advanced Residential Buildings (CARB) worked with BrightBuilt Home (BBH) to evaluate and optimize building systems. CARB’s work focused on a home built by Black Bros. Builders in Lincolnville, Maine (International Energy Conservation Code Climate Zone 6). As with most BBH projects to date, modular boxes were built by Keiser Homes in Oxford, Maine.

Urban Renewable Building And Neighborhood Optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

URBANopt is a user interface for creating and running district and city scale building energy simulations. The framework is built around the OpenStudio Urban Measures which are part of the OpenStudio project. Building footprints, building height, building type, and other data can be imported from public records or other sources. Footprints and locations for new buildings and district systems can also be specified. OpenStudio Measures are used to create starting point energy models and to model energy design features and efficiency measures for each building. URBANopt allows a user to pose several scenarios such as “what if 30% of themore » commercial retail buildings added roof top solar” or “what if all elementary schools converted to ground source heat pumps” and then visualize the impacts at a district or city scale. URBANopt is capable of modeling existing buildings, new construction, and district energy systems. URBANopt can be used to explore options for achieving Zero Energy across a collection of buildings (e.g., Zero Energy Districts).« less

Increasing energy efficiency level of building production based on applying modern mechanization facilities

NASA Astrophysics Data System (ADS)

Prokhorov, Sergey

2017-10-01

Building industry in a present day going through the hard times. Machine and mechanism exploitation cost, on a field of construction and installation works, takes a substantial part in total building construction expenses. There is a necessity to elaborate high efficient method, which allows not only to increase production, but also to reduce direct costs during machine fleet exploitation, and to increase its energy efficiency. In order to achieve the goal we plan to use modern methods of work production, hi-tech and energy saving machine tools and technologies, and use of optimal mechanization sets. As the optimization criteria there are exploitation prime cost and set efficiency. During actual task-solving process we made a conclusion, which shows that mechanization works, energy audit with production juxtaposition, prime prices and costs for energy resources allow to make complex machine fleet supply, improve ecological level and increase construction and installation work quality.

Strategies to Save 50% Site Energy in Grocery and General Merchandise Stores

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hirsch, A.; Hale, E.; Leach, M.

2011-03-01

This paper summarizes the methodology and main results of two recently published Technical Support Documents. These reports explore the feasibility of designing general merchandise and grocery stores that use half the energy of a minimally code-compliant building, as measured on a whole-building basis. We used an optimization algorithm to trace out a minimum cost curve and identify designs that satisfy the 50% energy savings goal. We started from baseline building energy use and progressed to more energy-efficient designs by sequentially adding energy design measures (EDMs). Certain EDMs figured prominently in reaching the 50% energy savings goal for both building types:more » (1) reduced lighting power density; (2) optimized area fraction and construction of view glass or skylights, or both, as part of a daylighting system tuned to 46.5 fc (500 lux); (3) reduced infiltration with a main entrance vestibule or an envelope air barrier, or both; and (4) energy recovery ventilators, especially in humid and cold climates. In grocery stores, the most effective EDM, which was chosen for all climates, was replacing baseline medium-temperature refrigerated cases with high-efficiency models that have doors.« less

Space-planning and structural solutions of low-rise buildings: Optimal selection methods

NASA Astrophysics Data System (ADS)

Gusakova, Natalya; Minaev, Nikolay; Filushina, Kristina; Dobrynina, Olga; Gusakov, Alexander

2017-11-01

The present study is devoted to elaboration of methodology used to select appropriately the space-planning and structural solutions in low-rise buildings. Objective of the study is working out the system of criteria influencing the selection of space-planning and structural solutions which are most suitable for low-rise buildings and structures. Application of the defined criteria in practice aim to enhance the efficiency of capital investments, energy and resource saving, create comfortable conditions for the population considering climatic zoning of the construction site. Developments of the project can be applied while implementing investment-construction projects of low-rise housing at different kinds of territories based on the local building materials. The system of criteria influencing the optimal selection of space-planning and structural solutions of low-rise buildings has been developed. Methodological basis has been also elaborated to assess optimal selection of space-planning and structural solutions of low-rise buildings satisfying the requirements of energy-efficiency, comfort and safety, and economical efficiency. Elaborated methodology enables to intensify the processes of low-rise construction development for different types of territories taking into account climatic zoning of the construction site. Stimulation of low-rise construction processes should be based on the system of approaches which are scientifically justified; thus it allows enhancing energy efficiency, comfort, safety and economical effectiveness of low-rise buildings.

Transaction-Based Building Controls Framework, Volume 1: Reference Guide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Somasundaram, Sriram; Pratt, Robert G.; Akyol, Bora A.

This document proposes a framework concept to achieve the objectives of raising buildings’ efficiency and energy savings potential benefitting building owners and operators. We call it a transaction-based framework, wherein mutually-beneficial and cost-effective market-based transactions can be enabled between multiple players across different domains. Transaction-based building controls are one part of the transactional energy framework. While these controls realize benefits by enabling automatic, market-based intra-building efficiency optimizations, the transactional energy framework provides similar benefits using the same market -based structure, yet on a larger scale and beyond just buildings, to the society at large.

A Statistical Analysis of the Economic Drivers of Battery Energy Storage in Commercial Buildings: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Long, Matthew; Simpkins, Travis; Cutler, Dylan

There is significant interest in using battery energy storage systems (BESS) to reduce peak demand charges, and therefore the life cycle cost of electricity, in commercial buildings. This paper explores the drivers of economic viability of BESS in commercial buildings through statistical analysis. A sample population of buildings was generated, a techno-economic optimization model was used to size and dispatch the BESS, and the resulting optimal BESS sizes were analyzed for relevant predictor variables. Explanatory regression analyses were used to demonstrate that peak demand charges are the most significant predictor of an economically viable battery, and that the shape ofmore » the load profile is the most significant predictor of the size of the battery.« less

A Statistical Analysis of the Economic Drivers of Battery Energy Storage in Commercial Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Long, Matthew; Simpkins, Travis; Cutler, Dylan

There is significant interest in using battery energy storage systems (BESS) to reduce peak demand charges, and therefore the life cycle cost of electricity, in commercial buildings. This paper explores the drivers of economic viability of BESS in commercial buildings through statistical analysis. A sample population of buildings was generated, a techno-economic optimization model was used to size and dispatch the BESS, and the resulting optimal BESS sizes were analyzed for relevant predictor variables. Explanatory regression analyses were used to demonstrate that peak demand charges are the most significant predictor of an economically viable battery, and that the shape ofmore » the load profile is the most significant predictor of the size of the battery.« less

Regionalized LCA-based optimization of building energy supply: method and case study for a Swiss municipality.

PubMed

Saner, Dominik; Vadenbo, Carl; Steubing, Bernhard; Hellweg, Stefanie

2014-07-01

This paper presents a regionalized LCA-based multiobjective optimization model of building energy demand and supply for the case of a Swiss municipality for the minimization of greenhouse gas emissions and particulate matter formation. The results show that the environmental improvement potential is very large: in the optimal case, greenhouse gas emissions from energy supply could be reduced by more than 75% and particulate emissions by over 50% in the municipality. This scenario supposes a drastic shift of heat supply systems from a fossil fuel dominated portfolio to a portfolio consisting of mainly heat pump and woodchip incineration systems. In addition to a change in heat supply technologies, roofs, windows and walls would need to be refurbished in more than 65% of the municipality's buildings. The full potential of the environmental impact reductions will hardly be achieved in reality, particularly in the short term, for example, because of financial constraints and social acceptance, which were not taken into account in this study. Nevertheless, the results of the optimization model can help policy makers to identify the most effective measures for improvement at the decision making level, for example, at the building level for refurbishment and selection of heating systems or at the municipal level for designing district heating networks. Therefore, this work represents a starting point for designing effective incentives to reduce the environmental impact of buildings. While the results of the optimization model are specific to the municipality studied, the model could readily be adapted to other regions.

Wireless sensor and actuator networks for lighting energy efficiency and user satisfaction

NASA Astrophysics Data System (ADS)

Wen, Yao-Jung

Buildings consume more than one third of the primary energy generated in the U.S., and lighting alone accounts for approximately 30% of the energy usage in commercial buildings. As the largest electricity consumer of all building electrical systems, lighting harbors the greatest potential for energy savings in the commercial sector. Fifty percent of current energy consumption could be reduced with energy-efficient lighting management strategies. While commercial products do exist, they are poorly received due to exorbitant retrofitting cost and unsatisfactory performance. As a result, most commercial buildings, especially legacy buildings, have not taken advantage of the opportunity to generate savings from lighting. The emergence of wireless sensor and actuator network (WSAN) technologies presents an alternative that circumvents costly rewiring and promises better performance than existing commercial lighting systems. The goal of this dissertation research is to develop a framework for wireless-networked lighting systems with increased cost effectiveness, energy efficiency, and user satisfaction. This research is realized through both theoretical developments and implementations. The theoretical research aims at developing techniques for harnessing WSAN technologies to lighting hardware and control strategies. Leveraging redundancy, a sensor validation and fusion algorithm is developed for extracting pertinent lighting information from the disturbance-prone desktop-mounted photosensors. An adaptive sensing strategy optimizes the timing of data acquisition and power-hungry wireless transmission of sensory feedback in real-time lighting control. Exploiting the individual addressability of wireless-enabled luminaires, a lighting optimization algorithm is developed to create the optimal lighting that minimizes energy usage while satisfying occupants' diverse lighting preferences. The wireless-networked lighting system was implemented and tested in a number of real-life settings. A human subject study conducted in a private office concluded that the research system was competitive with the commercial lighting system with much fewer retrofitting requirements. The system implemented in a shared-space office realized a self-configuring mesh network with wireless photosensors and light actuators, and demonstrated a 50% energy savings and increased performance when harvesting daylight through windows is possible. The cost analysis revealed a reasonable payback period after the system is optimized for commercialization and confirms the marketing feasibility.

Assessing the optimality of ASHRAE climate zones using high resolution meteorological data sets

NASA Astrophysics Data System (ADS)

Fils, P. D.; Kumar, J.; Collier, N.; Hoffman, F. M.; Xu, M.; Forbes, W.

2017-12-01

Energy consumed by built infrastructure constitutes a significant fraction of the nation's energy budget. According to 2015 US Energy Information Agency report, 41% of the energy used in the US was going to residential and commercial buildings. Additional research has shown that 32% of commercial building energy goes into heating and cooling the building. The American National Standards Institute and the American Society of Heating Refrigerating and Air-Conditioning Engineers Standard 90.1 provides climate zones for current state-of-practice since heating and cooling demands are strongly influenced by spatio-temporal weather variations. For this reason, we have been assessing the optimality of the climate zones using high resolution daily climate data from NASA's DAYMET database. We analyzed time series of meteorological data sets for all ASHRAE climate zones between 1980-2016 inclusively. We computed the mean, standard deviation, and other statistics for a set of meteorological variables (solar radiation, maximum and minimum temperature)within each zone. By plotting all the zonal statistics, we analyzed patterns and trends in those data over the past 36 years. We compared the means of each zone to its standard deviation to determine the range of spatial variability that exist within each zone. If the band around the mean is too large, it indicates that regions in the zone experience a wide range of weather conditions and perhaps a common set of building design guidelines would lead to a non-optimal energy consumption scenario. In this study we have observed a strong variation in the different climate zones. Some have shown consistent patterns in the past 36 years, indicating that the zone was well constructed, while others have greatly deviated from their mean indicating that the zone needs to be reconstructed. We also looked at redesigning the climate zones based on high resolution climate data. We are using building simulations models like EnergyPlus to develop optimal energy guidelines for each climate zone and quantify potential energy savings that can be realized by redesigning climate zones using state-of-the art data sets.

Rois Langner | NREL

Science.gov Websites

engineer in the Commercial Buildings Research Group at NREL since 2010. Her research efforts have focused optimize building design and performance for military and large commercial buildings. She has also worked continual energy improvement, and more recently is working to support the small commercial building sector

Achieving 50% Energy Savings in Office Buildings, Advanced Energy Design Guides: Office Buildings (Brochure)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

2014-09-01

This fact sheet summarizes recommendations for designing new office buildings that result in 50% less energy use than conventional designs meeting minimum code requirements. The recommendations are drawn from the Advanced Energy Design Guide for Small to Medium Office Buildings, an ASHRAE publication that provides comprehensive recommendations for designing low-energy-use office buildings with gross floor areas up to 100,000 ft2 (see sidebar). Designed as a stand-alone document, this fact sheet provides key principles and a set of prescriptive design recommendations appropriate for smaller office buildings with insufficient budgets to fully implement best practices for integrated design and optimized performance. Themore » recommendations have undergone a thorough analysis and review process through ASHRAE, and have been deemed the best combination of measures to achieve 50% savings in the greatest number of office buildings.« less

Energy Performance and Optimal Control of Air-conditioned Buildings Integrated with Phase Change Materials

NASA Astrophysics Data System (ADS)

Zhu, Na

This thesis presents an overview of the previous research work on dynamic characteristics and energy performance of buildings due to the integration of PCMs. The research work on dynamic characteristics and energy performance of buildings using PCMs both with and without air-conditioning is reviewed. Since the particular interest in using PCMs for free cooling and peak load shifting, specific research efforts on both subjects are reviewed separately. A simplified physical dynamic model of building structures integrated with SSPCM (shaped-stabilized phase change material) is developed and validated in this study. The simplified physical model represents the wall by 3 resistances and 2 capacitances and the PCM layer by 4 resistances and 2 capacitances respectively while the key issue is the parameter identification of the model. This thesis also presents the studies on the thermodynamic characteristics of buildings enhanced by PCM and on the investigation of the impacts of PCM on the building cooling load and peak cooling demand at different climates and seasons as well as the optimal operation and control strategies to reduce the energy consumption and energy cost by reducing the air-conditioning energy consumption and peak load. An office building floor with typical variable air volume (VAV) air-conditioning system is used and simulated as the reference building in the comparison study. The envelopes of the studied building are further enhanced by integrating the PCM layers. The building system is tested in two selected cities of typical climates in China including Hong Kong and Beijing. The cold charge and discharge processes, the operation and control strategies of night ventilation and the air temperature set-point reset strategy for minimizing the energy consumption and electricity cost are studied. This thesis presents the simulation test platform, the test results on the cold storage and discharge processes, the air-conditioning energy consumption and demand reduction potentials in typical air-conditioning seasons in typical China cites as well as the impacts of operation and control strategies.

Eric Wilson | NREL

Science.gov Websites

, developing an analysis framework and data visualization for national residential building stock models, and include developing multifamily modeling capabilities for the BEopt building energy optimization software

Improving Building Energy Simulation Programs Through Diagnostic Testing (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

2012-02-01

New test procedure evaluates quality and accuracy of energy analysis tools for the residential building retrofit market. Reducing the energy use of existing homes in the United States offers significant energy-saving opportunities, which can be identified through building simulation software tools that calculate optimal packages of efficiency measures. To improve the accuracy of energy analysis for residential buildings, the National Renewable Energy Laboratory's (NREL) Buildings Research team developed the Building Energy Simulation Test for Existing Homes (BESTEST-EX), a method for diagnosing and correcting errors in building energy audit software and calibration procedures. BESTEST-EX consists of building physics and utility billmore » calibration test cases, which software developers can use to compare their tools simulation findings to reference results generated with state-of-the-art simulation tools. Overall, the BESTEST-EX methodology: (1) Tests software predictions of retrofit energy savings in existing homes; (2) Ensures building physics calculations and utility bill calibration procedures perform to a minimum standard; and (3) Quantifies impacts of uncertainties in input audit data and occupant behavior. BESTEST-EX is helping software developers identify and correct bugs in their software, as well as develop and test utility bill calibration procedures.« less

Computer simulation for optimizing windbreak placement to save energy for heating and cooling buildings

Treesearch

Gordon M. Heisler

1991-01-01

Saving energy has recently acquired new importance because of increased concern for dwindling fossil fuel supplies and for the problem of carbon dioxide contributions to global climate change. Many studies have indicated that windbreaks have the ability to save energy for heating buildings. Suggested savings have ranged up 40 percent; though more commonly savings of...

Energy Integrated Design of Lighting, Heating, and Cooling Systems, and Its Effect on Building Energy Requirements.

ERIC Educational Resources Information Center

Meckler, Gershon

Comments on the need for integrated design of lighting, heating, and cooling systems. In order to eliminate the penalty of refrigerating the lighting heat, minimize the building non-usable space, and optimize the total energy input, a "systems approach" is recommended. This system would employ heat-recovery techniques based on the ability of the…

Agreement Technologies for Energy Optimization at Home.

PubMed

González-Briones, Alfonso; Chamoso, Pablo; De La Prieta, Fernando; Demazeau, Yves; Corchado, Juan M

2018-05-19

Nowadays, it is becoming increasingly common to deploy sensors in public buildings or homes with the aim of obtaining data from the environment and taking decisions that help to save energy. Many of the current state-of-the-art systems make decisions considering solely the environmental factors that cause the consumption of energy. These systems are successful at optimizing energy consumption; however, they do not adapt to the preferences of users and their comfort. Any system that is to be used by end-users should consider factors that affect their wellbeing. Thus, this article proposes an energy-saving system, which apart from considering the environmental conditions also adapts to the preferences of inhabitants. The architecture is based on a Multi-Agent System (MAS), its agents use Agreement Technologies (AT) to perform a negotiation process between the comfort preferences of the users and the degree of optimization that the system can achieve according to these preferences. A case study was conducted in an office building, showing that the proposed system achieved average energy savings of 17.15%.

Costs and Operating Dynamics of Integrating Distributed Energy Resources in Commercial and Industrial Buildings with Electric Vehicle Charging

NASA Astrophysics Data System (ADS)

Flores, Robert Joseph

Growing concerns over greenhouse gas and pollutant emissions have increased the pressure to shift energy conversion paradigms from current forms to more sustainable methods, such as through the use of distributed energy resources (DER) at industrial and commercial buildings. This dissertation is concerned with the optimal design and dispatch of a DER system installed at an industrial or commercial building. An optimization model that accurately captures typical utility costs and the physical constraints of a combined cooling, heating, and power (CCHP) system is designed to size and operate a DER system at a building. The optimization model is then used with cooperative game theory to evaluate the financial performance of a CCHP investment. The CCHP model is then modified to include energy storage, solar powered generators, alternative fuel sources, carbon emission limits, and building interactions with public and fleet PEVs. Then, a separate plugin electric vehicle (PEV) refueling model is developed to determine the cost to operate a public Level 3 fast charging station. The CCHP design and dispatch results show the size of the building load and consistency of the thermal loads are critical to positive financial performance. While using the CCHP system to produce cooling can provide savings, heat production drives positive financial performance. When designing the DER system to reduce carbon emissions, the use of renewable fuels can allow for a gas turbine system with heat recovery to reduce carbon emissions for a large university by 67%. Further reductions require large photovoltaic installations coupled with energy storage or the ability to export electricity back to the grid if costs are to remain relatively low. When considering Level 3 fast charging equipment, demand charges at low PEV travel levels are sufficiently high to discourage adoption. Integration of the equipment can reduce demand charge costs only if the building maximum demand does not coincide with PEV refueling. Electric vehicle refueling does not typically affect DER design at low PEV travel levels, but can as electric vehicle travel increases. However, as PEV travel increases, the stochastic nature of PEV refueling disappears, and the optimization problem may become deterministic.

Intelligent Controls for Net-Zero Energy Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Haorong; Cho, Yong; Peng, Dongming

2011-10-30

The goal of this project is to develop and demonstrate enabling technologies that can empower homeowners to convert their homes into net-zero energy buildings in a cost-effective manner. The project objectives and expected outcomes are as follows: • To develop rapid and scalable building information collection and modeling technologies that can obtain and process “as-built” building information in an automated or semiautomated manner. • To identify low-cost measurements and develop low-cost virtual sensors that can monitor building operations in a plug-n-play and low-cost manner. • To integrate and demonstrate low-cost building information modeling (BIM) technologies. • To develop decision supportmore » tools which can empower building owners to perform energy auditing and retrofit analysis. • To develop and demonstrate low-cost automated diagnostics and optimal control technologies which can improve building energy efficiency in a continual manner.« less

Proceedings of the workshop on the dynamic response of environmental control processes in buildings, Lafayette, Indiana, March 13-15, 1979

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tree, D.R.; McBride, M.F.

The purpose of this workshop was to consider how energy use in buildings can be reduced while maintaining the comfort of the occupants. It was postulated that optimization of energy use in buildings can be achieved through the use of operating strategies which consider the dynamic characteristics of comfort, the design and construction of the building, and the environmental control system. Working sessions were presented on equipment, controls, structures, human factors, circulation/distribution, design, operation and use pattern, management and codes, and energy storage. (LCL)

Optimization and Performance Study of Select Heating Ventilation and Air Conditioning Technologies for Commercial Buildings

NASA Astrophysics Data System (ADS)

Kamal, Rajeev

Buildings contribute a significant part to the electricity demand profile and peak demand for the electrical utilities. The addition of renewable energy generation adds additional variability and uncertainty to the power system. Demand side management in the buildings can help improve the demand profile for the utilities by shifting some of the demand from peak to off-peak times. Heating, ventilation and air-conditioning contribute around 45% to the overall demand of a building. This research studies two strategies for reducing the peak as well as shifting some demand from peak to off-peak periods in commercial buildings: 1. Use of gas heat pumps in place of electric heat pumps, and 2. Shifting demand for air conditioning from peak to off-peak by thermal energy storage in chilled water and ice. The first part of this study evaluates the field performance of gas engine-driven heat pumps (GEHP) tested in a commercial building in Florida. Four GEHP units of 8 Tons of Refrigeration (TR) capacity each providing air-conditioning to seven thermal zones in a commercial building, were instrumented for measuring their performance. The operation of these GEHPs was recorded for ten months, analyzed and compared with prior results reported in the literature. The instantaneous COPunit of these systems varied from 0.1 to 1.4 during typical summer week operation. The COP was low because the gas engines for the heat pumps were being used for loads that were much lower than design capacity which resulted in much lower efficiencies than expected. The performance of equivalent electric heat pump was simulated from a building energy model developed to mimic the measured building loads. An economic comparison of GEHPs and conventional electrical heat pumps was done based on the measured and simulated results. The average performance of the GEHP units was estimated to lie between those of EER-9.2 and EER-11.8 systems. The performance of GEHP systems suffers due to lower efficiency at part load operation. The study highlighted the need for optimum system sizing for GEHP/HVAC systems to meet the building load to obtain better performance in buildings. The second part of this study focusses on using chilled water or ice as thermal energy storage for shifting the air conditioning load from peak to off-peak in a commercial building. Thermal energy storage can play a very important role in providing demand-side management for diversifying the utility demand from buildings. Model of a large commercial office building is developed with thermal storage for cooling for peak power shifting. Three variations of the model were developed and analyzed for their performance with 1) ice storage, 2) chilled water storage with mixed storage tank and 3) chilled water storage with stratified tank, using EnergyPlus 8.5 software developed by the US Department of Energy. Operation strategy with tactical control to incorporate peak power schedule was developed using energy management system (EMS). The modeled HVAC system was optimized for minimum cost with the optimal storage capacity and chiller size using JEPlus. Based on the simulation, an optimal storage capacity of 40-45 GJ was estimated for the large office building model along with 40% smaller chiller capacity resulting in higher chiller part-load performance. Additionally, the auxiliary system like pump and condenser were also optimized to smaller capacities and thus resulting in less power demand during operation. The overall annual saving potential was found in the range of 7-10% for cooling electricity use resulting in 10-17% reduction in costs to the consumer. A possible annual peak shifting of 25-78% was found from the simulation results after comparing with the reference models. Adopting TES in commercial buildings and achieving 25% peak shifting could result in a reduction in peak summer demand of 1398 MW in Tampa.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosenberg, Michael; Jonlin, Duane; Nadel, Steven

Today’s building energy codes focus on prescriptive requirements for features of buildings that are directly controlled by the design and construction teams and verifiable by municipal inspectors. Although these code requirements have had a significant impact, they fail to influence a large slice of the building energy use pie – including not only miscellaneous plug loads, cooking equipment and commercial/industrial processes, but the maintenance and optimization of the code-mandated systems as well. Currently, code compliance is verified only through the end of construction, and there are no limits or consequences for the actual energy use in an occupied building. Inmore » the future, our suite of energy regulations will likely expand to include building efficiency, energy use or carbon emission budgets over their full life cycle. Intelligent building systems, extensive renewable energy, and a transition from fossil fuel to electric heating systems will likely be required to meet ultra-low-energy targets. This paper lays out the authors’ perspectives on how buildings may evolve over the course of the 21st century and the roles that codes and regulations will play in shaping those buildings of the future.« less

Building Performance Optimization while Empowering Occupants Toward Environmentally Sustainable Behavior through Continuous Monitoring and Diagnostics

DTIC Science & Technology

2016-12-01

investment at the PaANG installation. In compliance with the NIST handbook’s guidelines, the team used the actual energy prices of the buildings...Costing Manual for the Federal Energy Management Program. For example, the team used the actual energy price and the measured energy consumption at the...least 30% of a DOD building’s HVAC and plug load annual energy consumption can be saved through continuous diagnostics and controls, while empowering

Control of Smart Building Using Advanced SCADA

NASA Astrophysics Data System (ADS)

Samuel, Vivin Thomas

For complete control of the building, a proper SCADA implementation and the optimization strategy has to be build. For better communication and efficiency a proper channel between the Communication protocol and SCADA has to be designed. This paper concentrate mainly between the communication protocol, and the SCADA implementation, for a better optimization and energy savings is derived to large scale industrial buildings. The communication channel used in order to completely control the building remotely from a distant place. For an efficient result we consider the temperature values and the power ratings of the equipment so that while controlling the equipment, we are setting a threshold values for FDD technique implementation. Building management system became a vital source for any building to maintain it and for safety purpose. Smart buildings, refers to various distinct features, where the complete automation system, office building controls, data center controls. ELC's are used to communicate the load values of the building to the remote server from a far location with the help of an Ethernet communication channel. Based on the demand fluctuation and the peak voltage, the loads operate differently increasing the consumption rate thus results in the increase in the annual consumption bill. In modern days, saving energy and reducing the consumption bill is most essential for any building for a better and long operation. The equipment - monitored regularly and optimization strategy is implemented for cost reduction automation system. Thus results in the reduction of annual cost reduction and load lifetime increase.

IEA EBC Annex 66: Definition and simulation of occupant behavior in buildings

DOE PAGES

Yan, Da; Hong, Tianzhen; Dong, Bing; ...

2017-09-28

Here, more than 30% of the total primary energy in the world is consumed in buildings. It is crucial to reduce building energy consumption in order to preserve energy resources and mitigate global climate change. Building performance simulations have been widely used for the estimation and optimization of building performance, providing reference values for the assessment of building energy consumption and the effects of energy-saving technologies. Among the various factors influencing building energy consumption, occupant behavior has drawn increasing attention. Occupant behavior includes occupant presence, movement, and interaction with building energy devices and systems. However, there are gaps in occupantmore » behavior modeling as different energy modelers have employed varied data and tools to simulate occupant behavior, therefore producing different and incomparable results. Aiming to address these gaps, the International Energy Agency (IEA) Energy in Buildings and Community (EBC) Programme Annex 66 has established a scientific methodological framework for occupant behavior research, including data collection, behavior model representation, modeling and evaluation approaches, and the integration of behavior modeling tools with building performance simulation programs. Annex 66 also includes case studies and application guidelines to assist in building design, operation, and policymaking, using interdisciplinary approaches to reduce energy use in buildings and improve occupant comfort and productivity. This paper highlights the key research issues, methods, and outcomes pertaining to Annex 66, and offers perspectives on future research needs to integrate occupant behavior with the building life cycle.« less

IEA EBC Annex 66: Definition and simulation of occupant behavior in buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Da; Hong, Tianzhen; Dong, Bing

Here, more than 30% of the total primary energy in the world is consumed in buildings. It is crucial to reduce building energy consumption in order to preserve energy resources and mitigate global climate change. Building performance simulations have been widely used for the estimation and optimization of building performance, providing reference values for the assessment of building energy consumption and the effects of energy-saving technologies. Among the various factors influencing building energy consumption, occupant behavior has drawn increasing attention. Occupant behavior includes occupant presence, movement, and interaction with building energy devices and systems. However, there are gaps in occupantmore » behavior modeling as different energy modelers have employed varied data and tools to simulate occupant behavior, therefore producing different and incomparable results. Aiming to address these gaps, the International Energy Agency (IEA) Energy in Buildings and Community (EBC) Programme Annex 66 has established a scientific methodological framework for occupant behavior research, including data collection, behavior model representation, modeling and evaluation approaches, and the integration of behavior modeling tools with building performance simulation programs. Annex 66 also includes case studies and application guidelines to assist in building design, operation, and policymaking, using interdisciplinary approaches to reduce energy use in buildings and improve occupant comfort and productivity. This paper highlights the key research issues, methods, and outcomes pertaining to Annex 66, and offers perspectives on future research needs to integrate occupant behavior with the building life cycle.« less

Stochastic Control of Energy Efficient Buildings: A Semidefinite Programming Approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, Xiao; Dong, Jin; Djouadi, Seddik M

2015-01-01

The key goal in energy efficient buildings is to reduce energy consumption of Heating, Ventilation, and Air- Conditioning (HVAC) systems while maintaining a comfortable temperature and humidity in the building. This paper proposes a novel stochastic control approach for achieving joint performance and power control of HVAC. We employ a constrained Stochastic Linear Quadratic Control (cSLQC) by minimizing a quadratic cost function with a disturbance assumed to be Gaussian. The problem is formulated to minimize the expected cost subject to a linear constraint and a probabilistic constraint. By using cSLQC, the problem is reduced to a semidefinite optimization problem, wheremore » the optimal control can be computed efficiently by Semidefinite programming (SDP). Simulation results are provided to demonstrate the effectiveness and power efficiency by utilizing the proposed control approach.« less

Thermal environment analysis and energy conservation research of rural residence in cold regions of China based on BIM platform

NASA Astrophysics Data System (ADS)

Dong, J. Y.; Cheng, W.; Ma, C. P.; Xin, L. S.; Tan, Y. T.

2017-06-01

In order to study the issue of rural residential energy consumption in cold regions of China, modeled an architecture prototype based on BIM platform according to the affecting factors of rural residential thermal environment, and imported the virtual model which contains building information into energy analysis tools and chose the appropriate building orientation. By analyzing the energy consumption of the residential buildings with different enclosure structure forms, we designed the optimal energy-saving residence form. There is a certain application value of this method for researching the energy consumption and energy-saving design for the rural residence in cold regions of China.

Modeling carbon dioxide emissions reductions for three commercial reference buildings in Salt Lake City

NASA Astrophysics Data System (ADS)

Lucich, Stephen M.

In the United States, the buildings sector is responsible for approximately 40% of the national carbon dioxide (CO2) emissions. CO2 is created during the generation of heat and electricity, and has been linked to climate change, acid rain, a variety of health threats, surface water depletion, and the destruction of natural habitats. Building energy modeling is a powerful educational tool that building owners, architects, engineers, city planners, and policy makers can use to make informed decisions. The aim of this thesis is to simulate the reduction in CO2 emissions that may be achieved for three commercial buildings located in Salt Lake City, UT. The following two questions were used to guide this process: 1. How much can a building's annual CO2 emissions be reduced through a specific energy efficiency upgrade or policy? 2. How much can a building's annual CO2 emissions be reduced through the addition of a photovoltaic (PV) array? How large should the array be? Building energy simulations were performed with the Department of Energy's EnergyPlus software, commercial reference building models, and TMY3 weather data. The chosen models were a medium office building, a primary school, and a supermarket. Baseline energy consumption data were simulated for each model in order to identify changes that would have a meaningful impact. Modifications to the buildings construction and operation were considered before a PV array was incorporated. These modifications include (1) an improved building envelope, (2) reduced lighting intensity, and (3) modified HVAC temperature set points. The PV array sizing was optimized using a demand matching approach based on the method of least squares. The arrays tilt angle was optimized using the golden section search algorithm. Combined, energy efficiency upgrades and the PV array reduced building CO2 emissions by 58.6, 54.0, and 52.2% for the medium office, primary school, and supermarket, respectively. However, for these models, it was determined that the addition of a PV array is not feasible from a purely economic viewpoint. Several avenues for expansion of this research are presented in Chapter 5.

Energy demand and thermal comfort of HVAC systems with thermally activated building systems as a function of user profile

NASA Astrophysics Data System (ADS)

Pałaszyńska, Katarzyna; Bandurski, Karol; Porowski, Mieczysław

2017-11-01

Thermally Activated Building Systems (TABS) are a way to use building structure as a thermal energy storage. As a result, renewable energy sources may be used more efficiently. The paper presents numerical analysis of a HVAC system with TABS energy demand and indoor thermal comfort of a representative room in a non-residential building (governmental, commercial, educational). The purpose of analysis is to investigate the influence of a user profile on system performance. The time span of the analysis is one year - a typical meteorological year. The model was prepared using a generally accepted simulation tool - TRNSYS 17. The results help to better understand the interaction of a user profile with TABS. Therefore they are important for the development of optimal control algorithms for energy efficient buildings equipped with such systems.

A new procedure to analyze the effect of air changes in building energy consumption

PubMed Central

2014-01-01

Background Today, the International Energy Agency is working under good practice guides that integrate appropriate and cost effective technologies. In this paper a new procedure to define building energy consumption in accordance with the ISO 13790 standard was performed and tested based on real data from a Spanish region. Results Results showed that the effect of air changes on building energy consumption can be defined using the Weibull peak function model. Furthermore, the effect of climate change on building energy consumption under several different air changes was nearly nil during the summer season. Conclusions The procedure obtained could be the much sought-after solution to the problem stated by researchers in the past and future research works relating to this new methodology could help us define the optimal improvement in real buildings to reduce energy consumption, and its related carbon dioxide emissions, at minimal economical cost. PMID:24456655

FOSTERING SUSTAINABILITY: DESIGNING A GREEN SCIENCE BUILDING AT A SMALL MAINE COLLEGE

EPA Science Inventory

The overarching goal of the project ‘as to develop a feasibility study of building design and construction that takes into account the various local conditions, optimizes energy savings. use of building materials, and long term sustainability of the structur...

Fast exploration of an optimal path on the multidimensional free energy surface

PubMed Central

Chen, Changjun

2017-01-01

In a reaction, determination of an optimal path with a high reaction rate (or a low free energy barrier) is important for the study of the reaction mechanism. This is a complicated problem that involves lots of degrees of freedom. For simple models, one can build an initial path in the collective variable space by the interpolation method first and then update the whole path constantly in the optimization. However, such interpolation method could be risky in the high dimensional space for large molecules. On the path, steric clashes between neighboring atoms could cause extremely high energy barriers and thus fail the optimization. Moreover, performing simulations for all the snapshots on the path is also time-consuming. In this paper, we build and optimize the path by a growing method on the free energy surface. The method grows a path from the reactant and extends its length in the collective variable space step by step. The growing direction is determined by both the free energy gradient at the end of the path and the direction vector pointing at the product. With fewer snapshots on the path, this strategy can let the path avoid the high energy states in the growing process and save the precious simulation time at each iteration step. Applications show that the presented method is efficient enough to produce optimal paths on either the two-dimensional or the twelve-dimensional free energy surfaces of different small molecules. PMID:28542475

Sammy Houssainy | NREL

Science.gov Websites

focused on the design, analysis, and optimization of hybrid thermal and compressed air energy storage analysis and optimization, and the design of building and community scale systems. Education Ph.D

Aquifer Thermal Energy Storage for Seasonal Thermal Energy Balance

NASA Astrophysics Data System (ADS)

Rostampour, Vahab; Bloemendal, Martin; Keviczky, Tamas

2017-04-01

Aquifer Thermal Energy Storage (ATES) systems allow storing large quantities of thermal energy in subsurface aquifers enabling significant energy savings and greenhouse gas reductions. This is achieved by injection and extraction of water into and from saturated underground aquifers, simultaneously. An ATES system consists of two wells and operates in a seasonal mode. One well is used for the storage of cold water, the other one for the storage of heat. In warm seasons, cold water is extracted from the cold well to provide cooling to a building. The temperature of the extracted cold water increases as it passes through the building climate control systems and then gets simultaneously, injected back into the warm well. This procedure is reversed during cold seasons where the flow direction is reversed such that the warmer water is extracted from the warm well to provide heating to a building. From the perspective of building climate comfort systems, an ATES system is considered as a seasonal storage system that can be a heat source or sink, or as a storage for thermal energy. This leads to an interesting and challenging optimal control problem of the building climate comfort system that can be used to develop a seasonal-based energy management strategy. In [1] we develop a control-oriented model to predict thermal energy balance in a building climate control system integrated with ATES. Such a model however cannot cope with off-nominal but realistic situations such as when the wells are completely depleted, or the start-up phase of newly installed wells, etc., leading to direct usage of aquifer ambient temperature. Building upon our previous work in [1], we here extend the mathematical model for ATES system to handle the above mentioned more realistic situations. Using our improved models, one can more precisely predict system behavior and apply optimal control strategies to manage the building climate comfort along with energy savings and greenhouse gas reductions. [1] V. Rostampour and T. Keviczky, "Probabilistic Energy Management for Building Climate Comfort in Smart Thermal Grids with Seasonal Storage Systems," arXiv [math.OC], 10-Nov-2016.

Models for residential-and commercial-sector energy conservation analysis: Applications, limitations, and future potential

NASA Astrophysics Data System (ADS)

Cole, H. E.; Fuller, R. E.

1980-09-01

Four of the major models used by DOE for energy conservation analyses in the residential and commercial building sectors are reviewed and critically analyzed to determine how these models can serve as tools for DOE and its Conservation Policy Office in evaluating and quantifying their policy and program requirements. The most effective role for each model in addressing future issues of buildings energy conservation policy and analysis is assessed. The four models covered are: Oak Ridge Residential Energy Model; Micro Analysis of Transfers to Households/Comprehensive Human Resources Data System (MATH/CHRDS) Model; Oak Ridge Commercial Energy Model; and Brookhaven Buildings Energy Conservation Optimization Model (BECOM).

Data of cost-optimal solutions and retrofit design methods for school renovation in a warm climate.

PubMed

Zacà, Ilaria; Tornese, Giuliano; Baglivo, Cristina; Congedo, Paolo Maria; D'Agostino, Delia

2016-12-01

"Efficient Solutions and Cost-Optimal Analysis for Existing School Buildings" (Paolo Maria Congedo, Delia D'Agostino, Cristina Baglivo, Giuliano Tornese, Ilaria Zacà) [1] is the paper that refers to this article. It reports the data related to the establishment of several variants of energy efficient retrofit measures selected for two existing school buildings located in the Mediterranean area. In compliance with the cost-optimal analysis described in the Energy Performance of Buildings Directive and its guidelines (EU, Directive, EU 244,) [2], [3], these data are useful for the integration of renewable energy sources and high performance technical systems for school renovation. The data of cost-efficient high performance solutions are provided in tables that are explained within the following sections. The data focus on the describe school refurbishment sector to which European policies and investments are directed. A methodological approach already used in previous studies about new buildings is followed (Baglivo Cristina, Congedo Paolo Maria, D׳Agostino Delia, Zacà Ilaria, 2015; IlariaZacà, Delia D'Agostino, Paolo Maria Congedo, Cristina Baglivo; Baglivo Cristina, Congedo Paolo Maria, D'Agostino Delia, Zacà Ilaria, 2015; Ilaria Zacà, Delia D'Agostino, Paolo Maria Congedo, Cristina Baglivo, 2015; Paolo Maria Congedo, Cristina Baglivo, IlariaZacà, Delia D'Agostino,2015) [4], [5], [6], [7], [8]. The files give the cost-optimal solutions for a kindergarten (REF1) and a nursery (REF2) school located in Sanarica and Squinzano (province of Lecce Southern Italy). The two reference buildings differ for construction period, materials and systems. The eleven tables provided contain data about the localization of the buildings, geometrical features and thermal properties of the envelope, as well as the energy efficiency measures related to walls, windows, heating, cooling, dhw and renewables. Output values of energy consumption, gas emission and costs are given for a financial and a macro-economic analysis. This data article provides 288 and 96 combinations for REF1 and REF2, respectively. The output values are obtained using the software ProCasaClima 2015v.2.0.

Resource impact factor (RIF) approach to optimal use of energy resources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, R.R.

1976-10-01

A concept called the Resource Impact Factor (RIF) is presented as a means to quantify the social value of energy resources for buildings. The flow of various raw resources from the point of extraction to the building project boundary is shown, and a flow chart indicating the decision making process is given. (PMA)

Energy-Efficient Supermarket Heating, Ventilation, and Air Conditioning in Humid Climates in the United States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, J.

2015-03-01

Supermarkets are energy-intensive buildings that consume the greatest amount of electricity per square foot of building of any building type in the United States and represent 5% of total U.S. commercial building primary energy use (EIA 2005). Refrigeration and heating, ventilation, and air-conditioning (HVAC) systems are responsible for a large proportion of supermarkets’ total energy use. These two systems sometimes work together and sometimes compete, but the performance of one system always affects the performance of the other. To better understand these challenges and opportunities, the Commercial Buildings team at the National Renewable Energy Laboratory investigated several of the mostmore » promising strategies for providing energy-efficient HVAC for supermarkets and quantified the resulting energy use and costs using detailed simulations. This research effort was conducted on behalf of the U.S. Department of Energy (DOE) Commercial Building Partnerships (CBP) (Baechler et al. 2012; Parrish et al. 2013; Antonopoulos et al. 2014; Hirsch et al. 2014). The goal of CBP was to reduce energy use in the commercial building sector by creating, testing, and validating design concepts on the pathway to net zero energy commercial buildings. Several CBP partners owned or operated buildings containing supermarkets and were interested in optimizing the energy efficiency of supermarket HVAC systems in hot-humid climates. These partners included Walmart, Target, Whole Foods Market, SUPERVALU, and the Defense Commissary Agency.« less

Constructive singularities and energy efficiency of St. Petersburg historic circuses

NASA Astrophysics Data System (ADS)

Sysoeva, Elena; Trushina, Ekaterina

2017-10-01

The article is devoted to the design and construction of St. Petersburg circuses during the period since 1822 till nowadays. The article presents the characteristics of all eight historic buildings of St. Petersburg and their structural and architectural features. The article raises some issues of energy-optimal shape of a building on the example of St. Petersburg modern circus building. There are several historical drawings and photographs of the circus buildings. The article includes overview of normative regulation of circus buildings in Russia since the middle of the twentieth century and prospects for the future.

Improved Planning and Programming for Energy Efficient New Army Facilities

DTIC Science & Technology

1988-10-01

setpoints to occupant comfort must be considered carefully. Cutting off the HVAC system to the bedrooms during the day produced only small savings...functions of a building and minimizing the energy usage through optimization . It includes thermostats, time switches, programmable con- trollers...microprocessor systems, computers, and sensing devices that are linked with control and power components to manage energy use. This system optimizes load

Optimization of a hybrid electric power system design for large commercial buildings: An application design guide

NASA Astrophysics Data System (ADS)

Lee, Keun

Renewable energy in different forms has been used in various applications for survival since the beginning of human existence. However, there is a new dire need to reevaluate and recalibrate the overall energy issue both nationally and globally. This includes, but is not limited to, the finite availability of fossil fuel, energy sustainability with an increasing demand, escalating energy costs, environmental impact such as global warming and green-house gases, to name a few. This dissertation is primarily focused and related to the production and usage of electricity from non-hydro renewable sources. Among non-hydro renewable energy sources, electricity generation from wind and solar energy are the fastest-growing technologies in the United States and in the world. However, due to the intermittent nature of such renewable sources, energy storage devices are required to maintain proper operation of the grid system and in order to increase reliability. A hybrid system, as the name suggests, is a combination of different forms of non-renewable and renewable energy generation, with or without storage devices. Hybrid systems, when applied properly, are able to improve reliability and enhance stability, reduce emissions and noise pollution, provide continuous power, increase operation life, reduce cost, and efficiently use all available energy. In the United States (U.S.), buildings consume approximately 40% of the total primary energy and 74% of the total electricity. Therefore, reduction of energy consumption and improved energy efficiency in U.S. buildings will play a vital role in the overall energy picture. Electrical energy usage for any such building varies widely depending on age (construction technique), electricity and natural gas usage, appearance, location and climate. In this research, a hybrid system including non-renewable and renewable energy generation with storage devices specifically for building applications, is studied in detail. This research deals with the optimization of the hybrid system design (which consists of PV panels and/or wind turbines and/or storage devices for building applications) by developing an algorithm designed to make the system cost effective and energy efficient. Input data includes electrical load demand profile of the buildings, buildings' structural and geographical characteristics, real time pricing of electricity, and the costs of hybrid systems and storage devices. When the electrical load demand profile of a building that is being studied is available, a measured demand profile is directly used as input data. However, if that information is not available, a building's electric load demand is estimated using a developed algorithm based on three large data sources from a public domain, and used as input data. Using the acquired input data, the algorithm of this research is designed and programmed in order to determine the size of renewable components and to minimize the total yearly net cost. This dissertation also addresses the parametric sensitivity analysis to determine which factors are more significant and are expected to produce useful guidelines in the decision making process. An engineered and more practical, simplified solution has been provided for the optimized design process.

Agreement Technologies for Energy Optimization at Home

PubMed Central

2018-01-01

Nowadays, it is becoming increasingly common to deploy sensors in public buildings or homes with the aim of obtaining data from the environment and taking decisions that help to save energy. Many of the current state-of-the-art systems make decisions considering solely the environmental factors that cause the consumption of energy. These systems are successful at optimizing energy consumption; however, they do not adapt to the preferences of users and their comfort. Any system that is to be used by end-users should consider factors that affect their wellbeing. Thus, this article proposes an energy-saving system, which apart from considering the environmental conditions also adapts to the preferences of inhabitants. The architecture is based on a Multi-Agent System (MAS), its agents use Agreement Technologies (AT) to perform a negotiation process between the comfort preferences of the users and the degree of optimization that the system can achieve according to these preferences. A case study was conducted in an office building, showing that the proposed system achieved average energy savings of 17.15%. PMID:29783768

Solar plus: Optimization of distributed solar PV through battery storage and dispatchable load in residential buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Shaughnessy, Eric; Cutler, Dylan; Ardani, Kristen

As utility electricity rates evolve, pairing solar photovoltaic (PV) systems with battery storage has potential to ensure the value proposition of residential solar by mitigating economic uncertainty. In addition to batteries, load control technologies can reshape customer load profiles to optimize PV system use. The combination of PV, energy storage, and load control provides an integrated approach to PV deployment, which we call 'solar plus'. The U.S. National Renewable Energy Laboratory's Renewable Energy Optimization (REopt) model is utilized to evaluate cost-optimal technology selection, sizing, and dispatch in residential buildings under a variety of rate structures and locations. The REopt modelmore » is extended to include a controllable or 'smart' domestic hot water heater model and smart air conditioner model. We find that the solar plus approach improves end user economics across a variety of rate structures - especially those that are challenging for PV - including lower grid export rates, non-coincident time-of-use structures, and demand charges.« less

Solar plus: Optimization of distributed solar PV through battery storage and dispatchable load in residential buildings

DOE PAGES

O'Shaughnessy, Eric; Cutler, Dylan; Ardani, Kristen; ...

2018-01-11

As utility electricity rates evolve, pairing solar photovoltaic (PV) systems with battery storage has potential to ensure the value proposition of residential solar by mitigating economic uncertainty. In addition to batteries, load control technologies can reshape customer load profiles to optimize PV system use. The combination of PV, energy storage, and load control provides an integrated approach to PV deployment, which we call 'solar plus'. The U.S. National Renewable Energy Laboratory's Renewable Energy Optimization (REopt) model is utilized to evaluate cost-optimal technology selection, sizing, and dispatch in residential buildings under a variety of rate structures and locations. The REopt modelmore » is extended to include a controllable or 'smart' domestic hot water heater model and smart air conditioner model. We find that the solar plus approach improves end user economics across a variety of rate structures - especially those that are challenging for PV - including lower grid export rates, non-coincident time-of-use structures, and demand charges.« less

The Power of Flexibility: Autonomous Agents That Conserve Energy in Commercial Buildings

NASA Astrophysics Data System (ADS)

Kwak, Jun-young

Agent-based systems for energy conservation are now a growing area of research in multiagent systems, with applications ranging from energy management and control on the smart grid, to energy conservation in residential buildings, to energy generation and dynamic negotiations in distributed rural communities. Contributing to this area, my thesis presents new agent-based models and algorithms aiming to conserve energy in commercial buildings. More specifically, my thesis provides three sets of algorithmic contributions. First, I provide online predictive scheduling algorithms to handle massive numbers of meeting/event scheduling requests considering flexibility , which is a novel concept for capturing generic user constraints while optimizing the desired objective. Second, I present a novel BM-MDP ( Bounded-parameter Multi-objective Markov Decision Problem) model and robust algorithms for multi-objective optimization under uncertainty both at the planning and execution time. The BM-MDP model and its robust algorithms are useful in (re)scheduling events to achieve energy efficiency in the presence of uncertainty over user's preferences. Third, when multiple users contribute to energy savings, fair division of credit for such savings to incentivize users for their energy saving activities arises as an important question. I appeal to cooperative game theory and specifically to the concept of Shapley value for this fair division. Unfortunately, scaling up this Shapley value computation is a major hindrance in practice. Therefore, I present novel approximation algorithms to efficiently compute the Shapley value based on sampling and partitions and to speed up the characteristic function computation. These new models have not only advanced the state of the art in multiagent algorithms, but have actually been successfully integrated within agents dedicated to energy efficiency: SAVES, TESLA and THINC. SAVES focuses on the day-to-day energy consumption of individuals and groups in commercial buildings by reactively suggesting energy conserving alternatives. TESLA takes a long-range planning perspective and optimizes overall energy consumption of a large number of group events or meetings together. THINC provides an end-to-end integration within a single agent of energy efficient scheduling, rescheduling and credit allocation. While SAVES, TESLA and THINC thus differ in their scope and applicability, they demonstrate the utility of agent-based systems in actually reducing energy consumption in commercial buildings. I evaluate my algorithms and agents using extensive analysis on data from over 110,000 real meetings/events at multiple educational buildings including the main libraries at the University of Southern California. I also provide results on simulations and real-world experiments, clearly demonstrating the power of agent technology to assist human users in saving energy in commercial buildings.

Indoor Multi-Sensor Acquisition System for Projects on Energy Renovation of Buildings.

PubMed

Armesto, Julia; Sánchez-Villanueva, Claudio; Patiño-Cambeiro, Faustino; Patiño-Barbeito, Faustino

2016-05-28

Energy rehabilitation actions in buildings have become a great economic opportunity for the construction sector. They also constitute a strategic goal in the European Union (EU), given the energy dependence and the compromises with climate change of its member states. About 75% of existing buildings in the EU were built when energy efficiency codes had not been developed. Approximately 75% to 90% of those standing buildings are expected to remain in use in 2050. Significant advances have been achieved in energy analysis, simulation tools, and computer fluid dynamics for building energy evaluation. However, the gap between predictions and real savings might still be improved. Geomatics and computer science disciplines can really help in modelling, inspection, and diagnosis procedures. This paper presents a multi-sensor acquisition system capable of automatically and simultaneously capturing the three-dimensional geometric information, thermographic, optical, and panoramic images, ambient temperature map, relative humidity map, and light level map. The system integrates a navigation system based on a Simultaneous Localization and Mapping (SLAM) approach that allows georeferencing every data to its position in the building. The described equipment optimizes the energy inspection and diagnosis steps and facilitates the energy modelling of the building.

Indoor Multi-Sensor Acquisition System for Projects on Energy Renovation of Buildings

PubMed Central

Armesto, Julia; Sánchez-Villanueva, Claudio; Patiño-Cambeiro, Faustino; Patiño-Barbeito, Faustino

2016-01-01

Energy rehabilitation actions in buildings have become a great economic opportunity for the construction sector. They also constitute a strategic goal in the European Union (EU), given the energy dependence and the compromises with climate change of its member states. About 75% of existing buildings in the EU were built when energy efficiency codes had not been developed. Approximately 75% to 90% of those standing buildings are expected to remain in use in 2050. Significant advances have been achieved in energy analysis, simulation tools, and computer fluid dynamics for building energy evaluation. However, the gap between predictions and real savings might still be improved. Geomatics and computer science disciplines can really help in modelling, inspection, and diagnosis procedures. This paper presents a multi-sensor acquisition system capable of automatically and simultaneously capturing the three-dimensional geometric information, thermographic, optical, and panoramic images, ambient temperature map, relative humidity map, and light level map. The system integrates a navigation system based on a Simultaneous Localization and Mapping (SLAM) approach that allows georeferencing every data to its position in the building. The described equipment optimizes the energy inspection and diagnosis steps and facilitates the energy modelling of the building. PMID:27240379

Optimal Scheduling Method of Controllable Loads in DC Smart Apartment Building

NASA Astrophysics Data System (ADS)

Shimoji, Tsubasa; Tahara, Hayato; Matayoshi, Hidehito; Yona, Atsushi; Senjyu, Tomonobu

2015-12-01

From the perspective of global warming suppression and the depletion of energy resources, renewable energies, such as the solar collector (SC) and photovoltaic generation (PV), have been gaining attention in worldwide. Houses or buildings with PV and heat pumps (HPs) are recently being used in residential areas widely due to the time of use (TOU) electricity pricing scheme which is essentially inexpensive during middle-night and expensive during day-time. If fixed batteries and electric vehicles (EVs) can be introduced in the premises, the electricity cost would be even more reduced. While, if the occupants arbitrarily use these controllable loads respectively, power demand in residential buildings may fluctuate in the future. Thus, an optimal operation of controllable loads such as HPs, batteries and EV should be scheduled in the buildings in order to prevent power flow from fluctuating rapidly. This paper proposes an optimal scheduling method of controllable loads, and the purpose is not only the minimization of electricity cost for the consumers, but also suppression of fluctuation of power flow on the power supply side. Furthermore, a novel electricity pricing scheme is also suggested in this paper.

Analysis on energy consumption index system of thermal power plant

NASA Astrophysics Data System (ADS)

Qian, J. B.; Zhang, N.; Li, H. F.

2017-05-01

Currently, the increasingly tense situation in the context of resources, energy conservation is a realistic choice to ease the energy constraint contradictions, reduce energy consumption thermal power plants has become an inevitable development direction. And combined with computer network technology to build thermal power “small index” to monitor and optimize the management system, the power plant is the application of information technology and to meet the power requirements of the product market competition. This paper, first described the research status of thermal power saving theory, then attempted to establish the small index system and build “small index” monitoring and optimization management system in thermal power plant. Finally elaborated key issues in the field of small thermal power plant technical and economic indicators to be further studied and resolved.

Smart Building: Decision Making Architecture for Thermal Energy Management.

PubMed

Uribe, Oscar Hernández; Martin, Juan Pablo San; Garcia-Alegre, María C; Santos, Matilde; Guinea, Domingo

2015-10-30

Smart applications of the Internet of Things are improving the performance of buildings, reducing energy demand. Local and smart networks, soft computing methodologies, machine intelligence algorithms and pervasive sensors are some of the basics of energy optimization strategies developed for the benefit of environmental sustainability and user comfort. This work presents a distributed sensor-processor-communication decision-making architecture to improve the acquisition, storage and transfer of thermal energy in buildings. The developed system is implemented in a near Zero-Energy Building (nZEB) prototype equipped with a built-in thermal solar collector, where optical properties are analysed; a low enthalpy geothermal accumulation system, segmented in different temperature zones; and an envelope that includes a dynamic thermal barrier. An intelligent control of this dynamic thermal barrier is applied to reduce the thermal energy demand (heating and cooling) caused by daily and seasonal weather variations. Simulations and experimental results are presented to highlight the nZEB thermal energy reduction.

Energy Savings Measure Packages. Existing Homes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casey, Sean; Booten, Chuck

2011-11-01

This document presents the most cost effective Energy Savings Measure Packages (ESMP) for existing mixed-fuel and all electric homes to achieve 15% and 30% savings for each BetterBuildings grantee location across the United States. These packages are optimized for minimum cost to homeowners for source energy savings given the local climate and prevalent building characteristics (i.e. foundation types). Maximum cost savings are typically found between 30% and 50% energy savings over the reference home; this typically amounts to $300 - $700/year.

Energy Optimization Using a Case-Based Reasoning Strategy

PubMed Central

Herrera-Viedma, Enrique

2018-01-01

At present, the domotization of homes and public buildings is becoming increasingly popular. Domotization is most commonly applied to the field of energy management, since it gives the possibility of managing the consumption of the devices connected to the electric network, the way in which the users interact with these devices, as well as other external factors that influence consumption. In buildings, Heating, Ventilation and Air Conditioning (HVAC) systems have the highest consumption rates. The systems proposed so far have not succeeded in optimizing the energy consumption associated with a HVAC system because they do not monitor all the variables involved in electricity consumption. For this reason, this article presents an agent approach that benefits from the advantages provided by a Multi-Agent architecture (MAS) deployed in a Cloud environment with a wireless sensor network (WSN) in order to achieve energy savings. The agents of the MAS learn social behavior thanks to the collection of data and the use of an artificial neural network (ANN). The proposed system has been assessed in an office building achieving an average energy savings of 41% in the experimental group offices. PMID:29543729

Energy Optimization Using a Case-Based Reasoning Strategy.

PubMed

González-Briones, Alfonso; Prieto, Javier; De La Prieta, Fernando; Herrera-Viedma, Enrique; Corchado, Juan M

2018-03-15

At present, the domotization of homes and public buildings is becoming increasingly popular. Domotization is most commonly applied to the field of energy management, since it gives the possibility of managing the consumption of the devices connected to the electric network, the way in which the users interact with these devices, as well as other external factors that influence consumption. In buildings, Heating, Ventilation and Air Conditioning (HVAC) systems have the highest consumption rates. The systems proposed so far have not succeeded in optimizing the energy consumption associated with a HVAC system because they do not monitor all the variables involved in electricity consumption. For this reason, this article presents an agent approach that benefits from the advantages provided by a Multi-Agent architecture (MAS) deployed in a Cloud environment with a wireless sensor network (WSN) in order to achieve energy savings. The agents of the MAS learn social behavior thanks to the collection of data and the use of an artificial neural network (ANN). The proposed system has been assessed in an office building achieving an average energy savings of 41% in the experimental group offices.

CHP Fundamentals, NFMT High Performance Buildings (Presentation) – June 3, 2015

EPA Pesticide Factsheets

This presentation discusses how CHP can improve energy efficiency at a building or facility, and play a major role in reducing carbon emissions, optimizing fuel flexibility, lowering operating costs, and earning LEED points.

Assessment of solar-assisted gas-fired heat pump systems

NASA Technical Reports Server (NTRS)

Lansing, F. L.

1981-01-01

As a possible application for the Goldstone Energy Project, the performance of a 10 ton heat pump unit using a hybrid solar gas energy source was evaluated in an effort to optimize the solar collector size. The heat pump system is designed to provide all the cooling and/or heating requirements of a selected office building. The system performance is to be augmented in the heating mode by utilizing the waste heat from the power cycle. A simplified system analysis is described to assess and compute interrrelationships of the engine, heat pump, and solar and building performance parameters, and to optimize the solar concentrator/building area ratio for a minimum total system cost. In addition, four alternative heating cooling systems, commonly used for building comfort, are described; their costs are compared, and are found to be less competitive with the gas solar heat pump system at the projected solar equipment costs.

Model-based optimal design of active cool thermal energy storage for maximal life-cycle cost saving from demand management in commercial buildings

DOE PAGES

Cui, Borui; Gao, Dian-ce; Xiao, Fu; ...

2016-12-23

This article provides a method in comprehensive evaluation of cost-saving potential of active cool thermal energy storage (CTES) integrated with HVAC system for demand management in non-residential building. The active storage is beneficial by shifting peak demand for peak load management (PLM) as well as providing longer duration and larger capacity of demand response (DR). In this research, a model-based optimal design method using genetic algorithm is developed to optimize the capacity of active CTES aiming for maximizing the life-cycle cost saving concerning capital cost associated with storage capacity as well as incentives from both fast DR and PLM. Inmore » the method, the active CTES operates under a fast DR control strategy during DR events while under the storage-priority operation mode to shift peak demand during normal days. The optimal storage capacities, maximum annual net cost saving and corresponding power reduction set-points during DR event are obtained by using the proposed optimal design method. Lastly, this research provides guidance in comprehensive evaluation of cost-saving potential of CTES integrated with HVAC system for building demand management including both fast DR and PLM.« less

Model-based optimal design of active cool thermal energy storage for maximal life-cycle cost saving from demand management in commercial buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cui, Borui; Gao, Dian-ce; Xiao, Fu

This article provides a method in comprehensive evaluation of cost-saving potential of active cool thermal energy storage (CTES) integrated with HVAC system for demand management in non-residential building. The active storage is beneficial by shifting peak demand for peak load management (PLM) as well as providing longer duration and larger capacity of demand response (DR). In this research, a model-based optimal design method using genetic algorithm is developed to optimize the capacity of active CTES aiming for maximizing the life-cycle cost saving concerning capital cost associated with storage capacity as well as incentives from both fast DR and PLM. Inmore » the method, the active CTES operates under a fast DR control strategy during DR events while under the storage-priority operation mode to shift peak demand during normal days. The optimal storage capacities, maximum annual net cost saving and corresponding power reduction set-points during DR event are obtained by using the proposed optimal design method. Lastly, this research provides guidance in comprehensive evaluation of cost-saving potential of CTES integrated with HVAC system for building demand management including both fast DR and PLM.« less

Multi-Objectives Optimization of Ventilation Controllers for Passive Cooling in Residential Buildings

PubMed Central

Grygierek, Krzysztof; Ferdyn-Grygierek, Joanna

2018-01-01

An inappropriate indoor climate, mostly indoor temperature, may cause occupants’ discomfort. There are a great number of air conditioning systems that make it possible to maintain the required thermal comfort. Their installation, however, involves high investment costs and high energy demand. The study analyses the possibilities of limiting too high a temperature in residential buildings using passive cooling by means of ventilation with ambient cool air. A fuzzy logic controller whose aim is to control mechanical ventilation has been proposed and optimized. In order to optimize the controller, the modified Multiobjective Evolutionary Algorithm, based on the Strength Pareto Evolutionary Algorithm, has been adopted. The optimization algorithm has been implemented in MATLAB®, which is coupled by MLE+ with EnergyPlus for performing dynamic co-simulation between the programs. The example of a single detached building shows that the occupants’ thermal comfort in a transitional climate may improve significantly owing to mechanical ventilation controlled by the suggested fuzzy logic controller. When the system is connected to the traditional cooling system, it may further bring about a decrease in cooling demand. PMID:29642525

Development of an Integrated Process, Modeling and Simulation Platform for Performance-Based Design of Low-Energy and High IEQ Buildings

ERIC Educational Resources Information Center

Chen, Yixing

2013-01-01

The objective of this study was to develop a "Virtual Design Studio (VDS)": a software platform for integrated, coordinated and optimized design of green building systems with low energy consumption, high indoor environmental quality (IEQ), and high level of sustainability. The VDS is intended to assist collaborating architects,…

Thermal energy storage with phase change materials (PCMs) for the improvement of the energy performance of buildings

NASA Astrophysics Data System (ADS)

Soares, Nelson

The improvement of the energy efficiency of buildings during their operational phase is an active area of research. The markets are looking for new technologies, namely new thermal energy storage (TES) systems, which can be used to reduce buildings' dependency on fossil fuels, to make use of renewable energy sources and to contribute to match energy supply and demand efficiently. The main goals of this thesis are: (i) to evaluate the heat transfer with solid-liquid phase-change through small TES units filled with phase-change materials (PCMs), providing experimental data to be used in the design of new TES systems for buildings and in the validation of numerical models, and (ii) to provide some guidelines for the incorporation of PCM-drywalls in buildings aiming to reduce the energy demand for heating and cooling by making use of the latent heat from the phase-change processes of PCMs. The first part of this thesis refers to the experimental study of the heat transfer through a vertical stack of metallic rectangular cavities filled with different PCMs (a microencapsulated and a free-form PCM). The research carried out aims: (i) to analyze the melting and solidification processes of the PCM within the enclosures, (ii) to evaluate the influence of the aspect ratio of the cavities on the heat transfer and (iii) to discuss which type of PCM is better for specific cases. As a result, a big amount of experimental data for benchmarking and validation of numerical models is made available to the scientific community. Moreover, the results allow discussing which arrangement of the TES unit is better for specific applications considering the thermal regulation effect during charging, the influence of subcooling during discharging, and the influence of natural convection during both processes. It is shown that the effect of natural convection in the free-form PCM must be considered in any simulation to better describe the charging process. During discharging, subcooling must also be considered. On the contrary, the effect of natural convection and subcooling can be neglected when considering the microencapsulated PCM. The second part of this thesis concentrates on the dynamic simulation of energy in buildings considering the latent heat from PCMs' phase-change processes. The energy system under investigation is extended to an air-conditioned residential single-zone room. The main goals are: (i) to develop a holistic methodology to optimize the incorporation of PCM-drywalls in different typologies of construction and (ii) to provide guidelines for the incorporation of PCM-drywalls in different climates. Two studies are carried out: (i) a multi-dimensional optimization study combining EnergyPlus and GenOpt tools to optimize the incorporation of PCM-drywalls in lightweight steel-framed (LSF) residential buildings in Europe, and (ii) an EnergyPlus-based parametric study to optimize the incorporation of PCM-drywalls in heavyweight residential buildings in Kuwait. It is shown that an optimum PCM-drywall solution can be found for each European climate and that the incorporation of PCM-drywalls can contribute for heating and cooling energy savings in LSF construction. The results show that PCM-drywalls are particularly interesting for LSF construction in Mediterranean climates leading to higher energy savings. PCM-drywalls can also be used to reduce the annual energy demand for cooling in Kuwait by almost 5%.

A Wireless Platform for Energy Efficient Building Control Retrofits

DTIC Science & Technology

2012-08-01

University of Illinois at Urbana Champaign UTRC United Technologies Research Center VFD variable frequency drive WSN wireless sensor network ...demonstration area. .............................................................. 16 Table 4. Cost model for wireless sensor network ...buildings with MPC-based whole-building optimal control and (2) reduction in first costs achievable with a wireless sensor network (WSN)-based

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walker, Iain; Regnier, Cindy

Science at the Theater: Berkeley Lab scientists reveal the latest research on how to reduce your carbon footprint at home, work, and when you shop. Learn how even small choices can have a big impact. Iain Walker's research focuses on optimizing the energy use and comfort of buildings. He's a staff scientist in the Energy Performance of Buildings Group, which is part of Berkeley Lab's Environmen...tal Energy Technologies Division. He's also executive editor of Home Energy Magazine. Cindy Regnier is a Project Manager in the Environmental Energy Technologies Division at Berkeley Lab. She has over 13 years of mechanical engineeringmore » design experience, with a focus on low-energy buildings. Her projects have included several LEED Platinum buildings and the design of a 200,000 sf carbon neutral, net-zero energy science museum in San Francisco. Eric Masanet is Acting Deputy Leader of the International Energy Studies Group at Berkeley Lab. His research focuses on life-cycle assessments and energy efficiency analysis. He holds a joint research appointment in the Institute of Transportation Studies at UC Berkeley.« less

Optimal Decision Model for Sustainable Hospital Building Renovation—A Case Study of a Vacant School Building Converting into a Community Public Hospital

PubMed Central

Juan, Yi-Kai; Cheng, Yu-Ching; Perng, Yeng-Horng; Castro-Lacouture, Daniel

2016-01-01

Much attention has been paid to hospitals environments since modern pandemics have emerged. The building sector is considered to be the largest world energy consumer, so many global organizations are attempting to create a sustainable environment in building construction by reducing energy consumption. Therefore, maintaining high standards of hygiene while reducing energy consumption has become a major task for hospitals. This study develops a decision model based on genetic algorithms and A* graph search algorithms to evaluate existing hospital environmental conditions and to recommend an optimal scheme of sustainable renovation strategies, considering trade-offs among minimal renovation cost, maximum quality improvement, and low environmental impact. Reusing vacant buildings is a global and sustainable trend. In Taiwan, for example, more and more school space will be unoccupied due to a rapidly declining birth rate. Integrating medical care with local community elder-care efforts becomes important because of the aging population. This research introduces a model that converts a simulated vacant school building into a community public hospital renovation project in order to validate the solutions made by hospital managers and suggested by the system. The result reveals that the system performs well and its solutions are more successful than the actions undertaken by decision-makers. This system can improve traditional hospital building condition assessment while making it more effective and efficient. PMID:27347986

Optimal Decision Model for Sustainable Hospital Building Renovation-A Case Study of a Vacant School Building Converting into a Community Public Hospital.

PubMed

Juan, Yi-Kai; Cheng, Yu-Ching; Perng, Yeng-Horng; Castro-Lacouture, Daniel

2016-06-24

Much attention has been paid to hospitals environments since modern pandemics have emerged. The building sector is considered to be the largest world energy consumer, so many global organizations are attempting to create a sustainable environment in building construction by reducing energy consumption. Therefore, maintaining high standards of hygiene while reducing energy consumption has become a major task for hospitals. This study develops a decision model based on genetic algorithms and A* graph search algorithms to evaluate existing hospital environmental conditions and to recommend an optimal scheme of sustainable renovation strategies, considering trade-offs among minimal renovation cost, maximum quality improvement, and low environmental impact. Reusing vacant buildings is a global and sustainable trend. In Taiwan, for example, more and more school space will be unoccupied due to a rapidly declining birth rate. Integrating medical care with local community elder-care efforts becomes important because of the aging population. This research introduces a model that converts a simulated vacant school building into a community public hospital renovation project in order to validate the solutions made by hospital managers and suggested by the system. The result reveals that the system performs well and its solutions are more successful than the actions undertaken by decision-makers. This system can improve traditional hospital building condition assessment while making it more effective and efficient.

Neural network based optimal control of HVAC&R systems

NASA Astrophysics Data System (ADS)

Ning, Min

Heating, Ventilation, Air-Conditioning and Refrigeration (HVAC&R) systems have wide applications in providing a desired indoor environment for different types of buildings. It is well acknowledged that 30%-40% of the total energy generated is consumed by buildings and HVAC&R systems alone account for more than 50% of the building energy consumption. Low operational efficiency especially under partial load conditions and poor control are part of reasons for such high energy consumption. To improve energy efficiency, HVAC&R systems should be properly operated to maintain a comfortable and healthy indoor environment under dynamic ambient and indoor conditions with the least energy consumption. This research focuses on the optimal operation of HVAC&R systems. The optimization problem is formulated and solved to find the optimal set points for the chilled water supply temperature, discharge air temperature and AHU (air handling unit) fan static pressure such that the indoor environment is maintained with the least chiller and fan energy consumption. To achieve this objective, a dynamic system model is developed first to simulate the system behavior under different control schemes and operating conditions. The system model is modular in structure, which includes a water-cooled vapor compression chiller model and a two-zone VAV system model. A fuzzy-set based extended transformation approach is then applied to investigate the uncertainties of this model caused by uncertain parameters and the sensitivities of the control inputs with respect to the interested model outputs. A multi-layer feed forward neural network is constructed and trained in unsupervised mode to minimize the cost function which is comprised of overall energy cost and penalty cost when one or more constraints are violated. After training, the network is implemented as a supervisory controller to compute the optimal settings for the system. In order to implement the optimal set points predicted by the supervisory controller, a set of five adaptive PI (proportional-integral) controllers are designed for each of the five local control loops of the HVAC&R system. The five controllers are used to track optimal set points and zone air temperature set points. Parameters of these PI controllers are tuned online to reduce tracking errors. The updating rules are derived from Lyapunov stability analysis. Simulation results show that compared to the conventional night reset operation scheme, the optimal operation scheme saves around 10% energy under full load condition and 19% energy under partial load conditions.

Performative building envelope design correlated to solar radiation and cooling energy consumption

NASA Astrophysics Data System (ADS)

Jacky, Thiodore; Santoni

2017-11-01

Climate change as an ongoing anthropogenic environmental challenge is predominantly caused by an amplification in the amount of greenhouse gases (GHGs), notably carbon dioxide (CO2) in building sector. Global CO2 emissions are emitted from HVAC (Heating, Ventilation, and Air Conditioning) occupation to provide thermal comfort in building. In fact, the amount of energy used for cooling or heating building is implication of building envelope design. Building envelope acts as interface layer of heat transfer between outdoor environment and the interior of a building. It appears as wall, window, roof and external shading device. This paper examines performance of various design strategy on building envelope to limit solar radiation and reduce cooling loads in tropical climate. The design strategies are considering orientation, window to wall ratio, material properties, and external shading device. This research applied simulation method using Autodesk Ecotect to investigate simultaneously between variations of wall and window ratio, shading device composition and the implication to the amount of solar radiation, cooling energy consumption. Comparative analysis on the data will determine logical variation between opening and shading device composition and cooling energy consumption. Optimizing the building envelope design is crucial strategy for reducing CO2 emissions and long-term energy reduction in building sector. Simulation technology as feedback loop will lead to better performative building envelope.

A comprehensive framework to assess, model, and enhance the human role in conserving energy in commercial buildings

NASA Astrophysics Data System (ADS)

Azar, Elie

Energy conservation and sustainability are subjects of great interest today, especially in the commercial building sector which is witnessing a very high and growing demand for energy. Traditionally, efforts to reduce energy consumption in this sector consisted of researching and developing energy efficient building technologies and systems. On the other hand, recent studies indicate that human actions are major determinants of building energy performance and can lead to excessive energy use even in advanced low-energy buildings. As a result, it is essential to determine if the approach to future energy reduction initiatives should remain solely technology-focused, or if a human-focused approach is also needed to complement advancements in technology and improve building operation and performance. In practice, while technology-focused solutions have been extensively researched, promoted, and adopted in commercial buildings, research efforts on the role of human actions and energy use behaviors in energy conservation remain very limited. This study fills the missing gap in literature by presenting a comprehensive framework to (1) understand and quantify the influence of human actions on building energy performance, (2) model building occupants' energy use behaviors and account for potential changes in these behaviors over time, and (3) test and optimize different human-focused energy reduction interventions to increase their adoption in commercial buildings. Results are significant and prove that human actions have a major role to play in reducing the energy intensity of the commercial building sector. This sheds the light on the need for a shift in how people currently use and control different buildings systems, as this is crucial to ensure efficient building operation and to maximize the return on investment in energy-efficient technologies. Furthermore, this study proposes methods and tools that can be applied on any individual or groups of commercial buildings to evaluate the human impact on their energy performance. This is expected to boost research on the topic and promote the integration of human-focused interventions in large-scale energy reduction initiatives and policies. Finally, this dissertation presents a roadmap for the future challenges to energy conservation and the steps to take towards a more sustainable building sector and society.

Data analytics and optimization of an ice-based energy storage system for commercial buildings

DOE PAGES

Luo, Na; Hong, Tianzhen; Li, Hui; ...

2017-07-25

Ice-based thermal energy storage (TES) systems can shift peak cooling demand and reduce operational energy costs (with time-of-use rates) in commercial buildings. The accurate prediction of the cooling load, and the optimal control strategy for managing the charging and discharging of a TES system, are two critical elements to improving system performance and achieving energy cost savings. This study utilizes data-driven analytics and modeling to holistically understand the operation of an ice–based TES system in a shopping mall, calculating the system’s performance using actual measured data from installed meters and sensors. Results show that there is significant savings potential whenmore » the current operating strategy is improved by appropriately scheduling the operation of each piece of equipment of the TES system, as well as by determining the amount of charging and discharging for each day. A novel optimal control strategy, determined by an optimization algorithm of Sequential Quadratic Programming, was developed to minimize the TES system’s operating costs. Three heuristic strategies were also investigated for comparison with our proposed strategy, and the results demonstrate the superiority of our method to the heuristic strategies in terms of total energy cost savings. Specifically, the optimal strategy yields energy costs of up to 11.3% per day and 9.3% per month compared with current operational strategies. A one-day-ahead hourly load prediction was also developed using machine learning algorithms, which facilitates the adoption of the developed data analytics and optimization of the control strategy in a real TES system operation.« less

Data analytics and optimization of an ice-based energy storage system for commercial buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Na; Hong, Tianzhen; Li, Hui

Ice-based thermal energy storage (TES) systems can shift peak cooling demand and reduce operational energy costs (with time-of-use rates) in commercial buildings. The accurate prediction of the cooling load, and the optimal control strategy for managing the charging and discharging of a TES system, are two critical elements to improving system performance and achieving energy cost savings. This study utilizes data-driven analytics and modeling to holistically understand the operation of an ice–based TES system in a shopping mall, calculating the system’s performance using actual measured data from installed meters and sensors. Results show that there is significant savings potential whenmore » the current operating strategy is improved by appropriately scheduling the operation of each piece of equipment of the TES system, as well as by determining the amount of charging and discharging for each day. A novel optimal control strategy, determined by an optimization algorithm of Sequential Quadratic Programming, was developed to minimize the TES system’s operating costs. Three heuristic strategies were also investigated for comparison with our proposed strategy, and the results demonstrate the superiority of our method to the heuristic strategies in terms of total energy cost savings. Specifically, the optimal strategy yields energy costs of up to 11.3% per day and 9.3% per month compared with current operational strategies. A one-day-ahead hourly load prediction was also developed using machine learning algorithms, which facilitates the adoption of the developed data analytics and optimization of the control strategy in a real TES system operation.« less

A Fast Evaluation Method for Energy Building Consumption Based on the Design of Experiments

NASA Astrophysics Data System (ADS)

Belahya, Hocine; Boubekri, Abdelghani; Kriker, Abdelouahed

2017-08-01

Building sector is one of the effective consumer energy by 42% in Algeria. The need for energy has continued to grow, in inordinate way, due to lack of legislation on energy performance in this large consumer sector. Another reason is the simultaneous change of users’ requirements to maintain their comfort, especially summer in dry lands and parts of southern Algeria, where the town of Ouargla presents a typical example which leads to a large amount of electricity consumption through the use of air conditioning. In order to achieve a high performance envelope of the building, an optimization of major parameters building envelope is required, using design of experiments (DOE), can determine the most effective parameters and eliminate the less importance. The study building is often complex and time consuming due to the large number of parameters to consider. This study focuses on reducing the computing time and determines the major parameters of building energy consumption, such as area of building, factor shape, orientation, ration walls to windows …etc to make some proposal models in order to minimize the seasonal energy consumption due to air conditioning needs.

Energy efficiency façade design in high-rise apartment buildings using the calculation of solar heat transfer through windows with shading devices

NASA Astrophysics Data System (ADS)

Ha, P. T. H.

2018-04-01

The architectural design orientation at the first design stage plays a key role and has a great impact on the energy consumption of a building throughout its life-cycle. To provide designers with a simple and useful tool in quantitatively determining and simply optimizing the energy efficiency of a building at the very first stage of conceptual design, a factor namely building envelope energy efficiency (Khqnl ) should be investigated and proposed. Heat transfer through windows and other glazed areas of mezzanine floors accounts for 86% of overall thermal transfer through building envelope, so the factor Khqnl of high-rise buildings largely depends on shading solutions. The author has established tables and charts to make reference to the values of Khqnl factor in certain high-rise apartment buildings in Hanoi calculated with a software program subject to various inputs including: types and sizes of shading devices, building orientations and at different points of time to be respectively analyzed. It is possible and easier for architects to refer to these tables and charts in façade design for a higher level of energy efficiency.

Technology and Performance Analysis Tools | Energy Analysis | NREL

Science.gov Websites

optimize renewable energy and energy efficiency technologies for your project. Many of these tools can be the consumer or energy professional. Biomass Scenario Model (BSM) Determine which supply chain changes (BLCC) Analyze capital investments in buildings. Includes the Energy Escalation Rate Calculator 2.0-15

From Zero Energy Buildings to Zero Energy Districts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Polly, Ben; Kutscher, Chuck; Macumber, Dan

Some U.S. cities are planning advanced districts that have goals for zero energy, water, waste, and/or greenhouse gas emissions. From an energy perspective, zero energy districts present unique opportunities to cost-effectively achieve high levels of energy efficiency and renewable energy penetration across a collection of buildings that may be infeasible at the individual building scale. These high levels of performance are accomplished through district energy systems that harness renewable and wasted energy at large scales and flexible building loads that coordinate with variable renewable energy supply. Unfortunately, stakeholders face a lack of documented processes, tools, and best practices to assistmore » them in achieving zero energy districts. The National Renewable Energy Laboratory (NREL) is partnering on two new district projects in Denver: the National Western Center and the Sun Valley Neighborhood. We are working closely with project stakeholders in their zero energy master planning efforts to develop the resources needed to resolve barriers and create replicable processes to support future zero energy district efforts across the United States. Initial results of these efforts include the identification and description of key zero energy district design principles (maximizing building efficiency, solar potential, renewable thermal energy, and load control), economic drivers, and master planning principles. The work has also resulted in NREL making initial enhancements to the U.S. Department of Energy's open source building energy modeling platform (OpenStudio and EnergyPlus) with the long-term goal of supporting the design and optimization of energy districts.« less

Smart Building: Decision Making Architecture for Thermal Energy Management

PubMed Central

Hernández Uribe, Oscar; San Martin, Juan Pablo; Garcia-Alegre, María C.; Santos, Matilde; Guinea, Domingo

2015-01-01

Smart applications of the Internet of Things are improving the performance of buildings, reducing energy demand. Local and smart networks, soft computing methodologies, machine intelligence algorithms and pervasive sensors are some of the basics of energy optimization strategies developed for the benefit of environmental sustainability and user comfort. This work presents a distributed sensor-processor-communication decision-making architecture to improve the acquisition, storage and transfer of thermal energy in buildings. The developed system is implemented in a near Zero-Energy Building (nZEB) prototype equipped with a built-in thermal solar collector, where optical properties are analysed; a low enthalpy geothermal accumulation system, segmented in different temperature zones; and an envelope that includes a dynamic thermal barrier. An intelligent control of this dynamic thermal barrier is applied to reduce the thermal energy demand (heating and cooling) caused by daily and seasonal weather variations. Simulations and experimental results are presented to highlight the nZEB thermal energy reduction. PMID:26528978

Rapid Deployment of Optimal Control for Building HVAC Systems using Innovative Software Tools and a Hybrid Heuristic/Model Based Control Approach

DTIC Science & Technology

2017-03-21

Energy and Water Projects March 21, 2017 REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 Public reporting burden for this collection of...included reduced system energy use and cost as well as improved performance driven by autonomous commissioning and optimized system control. In the end...improve system performance and reduce energy use and cost. However, implementing these solutions into the extremely heterogeneous and often

Equation-based languages – A new paradigm for building energy modeling, simulation and optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wetter, Michael; Bonvini, Marco; Nouidui, Thierry S.

Most of the state-of-the-art building simulation programs implement models in imperative programming languages. This complicates modeling and excludes the use of certain efficient methods for simulation and optimization. In contrast, equation-based modeling languages declare relations among variables, thereby allowing the use of computer algebra to enable much simpler schematic modeling and to generate efficient code for simulation and optimization. We contrast the two approaches in this paper. We explain how such manipulations support new use cases. In the first of two examples, we couple models of the electrical grid, multiple buildings, HVAC systems and controllers to test a controller thatmore » adjusts building room temperatures and PV inverter reactive power to maintain power quality. In the second example, we contrast the computing time for solving an optimal control problem for a room-level model predictive controller with and without symbolic manipulations. As a result, exploiting the equation-based language led to 2, 200 times faster solution« less

Equation-based languages – A new paradigm for building energy modeling, simulation and optimization

DOE PAGES

Wetter, Michael; Bonvini, Marco; Nouidui, Thierry S.

2016-04-01

Most of the state-of-the-art building simulation programs implement models in imperative programming languages. This complicates modeling and excludes the use of certain efficient methods for simulation and optimization. In contrast, equation-based modeling languages declare relations among variables, thereby allowing the use of computer algebra to enable much simpler schematic modeling and to generate efficient code for simulation and optimization. We contrast the two approaches in this paper. We explain how such manipulations support new use cases. In the first of two examples, we couple models of the electrical grid, multiple buildings, HVAC systems and controllers to test a controller thatmore » adjusts building room temperatures and PV inverter reactive power to maintain power quality. In the second example, we contrast the computing time for solving an optimal control problem for a room-level model predictive controller with and without symbolic manipulations. As a result, exploiting the equation-based language led to 2, 200 times faster solution« less

Economic aspects of possible residential heating conservation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hopkowicz, M.; Szul, A.

1995-12-31

The paper presents methods of evaluation of energy and economy related effects of different actions aimed at conservation in residential buildings. It identifies also the method of selecting the most effective way of distribution funds assigned to weatherization as well as necessary improvements to be implemented within the heating node and the internal heating system of the building. The analysis of data gathered for four 11-stories high residential buildings of {open_quotes}Zeran{close_quotes} type being subject of the Conservation Demonstrative Project, included a differentiated scope of weatherization efforts and various actions aimed at system upgrading. Basing upon the discussion of the splitmore » of heat losses in a building as well as the established energy savings for numerous options of upgrading works, the main problem has been defined. It consists in optimal distribution of financial means for the discussed measures if the total amount of funds assigned for modifications is defined. The method based upon the principle of relative increments has been suggested. The economical and energy specifications of the building and its components, required for this method have also been elaborated. The application of this method allowed to define the suggested optimal scope of actions within the entire fund assigned for the comprehensive weatherization.« less

Image processing occupancy sensor

DOEpatents

Brackney, Larry J.

2016-09-27

A system and method of detecting occupants in a building automation system environment using image based occupancy detection and position determinations. In one example, the system includes an image processing occupancy sensor that detects the number and position of occupants within a space that has controllable building elements such as lighting and ventilation diffusers. Based on the position and location of the occupants, the system can finely control the elements to optimize conditions for the occupants, optimize energy usage, among other advantages.

Fuzzy Linguistic Knowledge Based Behavior Extraction for Building Energy Management Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dumidu Wijayasekara; Milos Manic

2013-08-01

Significant portion of world energy production is consumed by building Heating, Ventilation and Air Conditioning (HVAC) units. Thus along with occupant comfort, energy efficiency is also an important factor in HVAC control. Modern buildings use advanced Multiple Input Multiple Output (MIMO) control schemes to realize these goals. However, since the performance of HVAC units is dependent on many criteria including uncertainties in weather, number of occupants, and thermal state, the performance of current state of the art systems are sub-optimal. Furthermore, because of the large number of sensors in buildings, and the high frequency of data collection, large amount ofmore » information is available. Therefore, important behavior of buildings that compromise energy efficiency or occupant comfort is difficult to identify. This paper presents an easy to use and understandable framework for identifying such behavior. The presented framework uses human understandable knowledge-base to extract important behavior of buildings and present it to users via a graphical user interface. The presented framework was tested on a building in the Pacific Northwest and was shown to be able to identify important behavior that relates to energy efficiency and occupant comfort.« less

The improvement of thermal characteristics of autoclave aerated concrete for energy efficient high-rise buildings application

NASA Astrophysics Data System (ADS)

Khavanov, Pavel; Fomina, Ekaterina; Kozhukhova, Natalia

2018-03-01

Nowadays, the problem of energy saving is very relevant. One of the ways to reduction energy consumption in construction materials production and construction of civil and industrial high-rise buildings is the application of claddings with heat-insulating performance. The concept of energy efficiency of high-rise buildings is closely related to environmental aspect and sustainability of applied construction materials; reducing service costs; energy saving and microclimate comfortability. A complexity of architectural and structural design as well as aesthetic characteristics of construction materials are also should be considered. The high interest focused on materials with combined properties. This work is oriented on the study of energy efficiency of buildings by improving heat-insulation and strength performance of autoclave aerated concrete. The applied method of sulfate activation of lime allows monitoring phase and structure formation in aerated concrete. The optimal mix design of aerated concrete with the compressive strength up to 8.5 MPa and decreased density up to 760 kg/m3 was proposed. Analysis of structure at macro-and microscale was performed as well as the criteria of an optimal porosity formation was considered a number, size, shape of pore and density of interior partition. SEM analysis and BET method were performed in this research work. The research results demonstrated the correlation between structure and vapor permeability resistance, also it was found that the increase of strength can lead to reduction of thermal conductivity.

An Exploration of the Relationship between Improvements in Energy Efficiency and Life-Cycle Energy and Carbon Emissions using the BIRDS Low-Energy Residential Database.

PubMed

Kneifel, Joshua; O'Rear, Eric; Webb, David; O'Fallon, Cheyney

2018-02-01

To conduct a more complete analysis of low-energy and net-zero energy buildings that considers both the operating and embodied energy/emissions, members of the building community look to life-cycle assessment (LCA) methods. This paper examines differences in the relative impacts of cost-optimal energy efficiency measure combinations depicting residential buildings up to and beyond net-zero energy consumption on operating and embodied flows using data from the Building Industry Reporting and Design for Sustainability (BIRDS) Low-Energy Residential Database. Results indicate that net-zero performance leads to a large increase in embodied flows (over 40%) that offsets some of the reductions in operational flows, but overall life-cycle flows are still reduced by over 60% relative to the state energy code. Overall, building designs beyond net-zero performance can partially offset embodied flows with negative operational flows by replacing traditional electricity generation with solar production, but would require an additional 8.34 kW (18.54 kW in total) of due south facing solar PV to reach net-zero total life-cycle flows. Such a system would meet over 239% of operational consumption of the most energy efficient design considered in this study and over 116% of a state code-compliant building design in its initial year of operation.

Putting Carbon in its Place: What You Can Do (LBNL Science at the Theater)

ScienceCinema

Walker, Iain; Regnier, Cindy [LBNL, Environmental Energy Technologies Division; Miller, Jeff; Masanet, Eric

2018-06-28

Science at the Theater: Berkeley Lab scientists reveal the latest research on how to reduce your carbon footprint at home, work, and when you shop. Learn how even small choices can have a big impact. Iain Walker's research focuses on optimizing the energy use and comfort of buildings. He's a staff scientist in the Energy Performance of Buildings Group, which is part of Berkeley Lab's Environmen...tal Energy Technologies Division. He's also executive editor of Home Energy Magazine. Cindy Regnier is a Project Manager in the Environmental Energy Technologies Division at Berkeley Lab. She has over 13 years of mechanical engineering design experience, with a focus on low-energy buildings. Her projects have included several LEED Platinum buildings and the design of a 200,000 sf carbon neutral, net-zero energy science museum in San Francisco. Eric Masanet is Acting Deputy Leader of the International Energy Studies Group at Berkeley Lab. His research focuses on life-cycle assessments and energy efficiency analysis. He holds a joint research appointment in the Institute of Transportation Studies at UC Berkeley.

Applications of Optimal Building Energy System Selection and Operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marnay, Chris; Stadler, Michael; Siddiqui, Afzal

2011-04-01

Berkeley Lab has been developing the Distributed Energy Resources Customer Adoption Model (DER-CAM) for several years. Given load curves for energy services requirements in a building microgrid (u grid), fuel costs and other economic inputs, and a menu of available technologies, DER-CAM finds the optimum equipment fleet and its optimum operating schedule using a mixed integer linear programming approach. This capability is being applied using a software as a service (SaaS) model. Optimisation problems are set up on a Berkeley Lab server and clients can execute their jobs as needed, typically daily. The evolution of this approach is demonstrated bymore » description of three ongoing projects. The first is a public access web site focused on solar photovoltaic generation and battery viability at large commercial and industrial customer sites. The second is a building CO2 emissions reduction operations problem for a University of California, Davis student dining hall for which potential investments are also considered. And the third, is both a battery selection problem and a rolling operating schedule problem for a large County Jail. Together these examples show that optimization of building u grid design and operation can be effectively achieved using SaaS.« less

Environmental and economic evaluation of natural capital appropriation through building construction: practical case study in the Italian context.

PubMed

Bastianoni, Simone; Galli, Alessandro; Pulselli, Riccardo Maria; Niccolucci, Valentina

2007-11-01

This paper focuses on appropriation of natural capital through construction of buildings. The ecological footprint and the Costanza natural capital concepts are applied. The environmental consequences of human settlement are currently of great concern, and a need is felt to reduce the impact of building on the environment. The embodied energy of building materials and the "land area" required to sustain their production are considered to evaluate the demand on nature of this activity. The ecological footprints of 2 typical Italian buildings are compared. The paper also focuses on how to reduce the natural capital appropriation of building construction by means of environmentally inexpensive materials, renewable energy resources, and optimization of the use of bioproductive land by construction of multistoried buildings. Finally, to allocate an environmental load of buildings, an economic evaluation of natural capital appropriation through building construction is proposed.

Performance optimization of the power user electric energy data acquire system based on MOEA/D evolutionary algorithm

NASA Astrophysics Data System (ADS)

Ding, Zhongan; Gao, Chen; Yan, Shengteng; Yang, Canrong

2017-10-01

The power user electric energy data acquire system (PUEEDAS) is an important part of smart grid. This paper builds a multi-objective optimization model for the performance of the PUEEADS from the point of view of the combination of the comprehensive benefits and cost. Meanwhile, the Chebyshev decomposition approach is used to decompose the multi-objective optimization problem. We design a MOEA/D evolutionary algorithm to solve the problem. By analyzing the Pareto optimal solution set of multi-objective optimization problem and comparing it with the monitoring value to grasp the direction of optimizing the performance of the PUEEDAS. Finally, an example is designed for specific analysis.

10 CFR 436.18 - Measuring cost-effectiveness.

Code of Federal Regulations, 2010 CFR

2010-01-01

... water system, considered in determining such matters as the optimal size of a solar energy system, the... building energy or water system with an energy or water conservation measure by retrofit to an existing... estimated payback time is significantly less than the useful life of that system, and of the Federal...

10 CFR 436.18 - Measuring cost-effectiveness.

Code of Federal Regulations, 2011 CFR

2011-01-01

... water system, considered in determining such matters as the optimal size of a solar energy system, the... building energy or water system with an energy or water conservation measure by retrofit to an existing... estimated payback time is significantly less than the useful life of that system, and of the Federal...

Selection and Implementation of Single Building EMCS (Energy Monitoring and Control Systems).

DTIC Science & Technology

1983-08-01

Setpoint Night Setback 161 Figure 20: Dual Setpoint Night Setback/up 162 Figure 21: Centrifugal Chiller Reset 166 Figure 22: Centrifugal Chiller Capacity...Program outputs. Hot water temperature. Application notes. A dedicated local loop controller may be implemented. Chiller optimization . The chiller ... optimization program can be implemented in chilled water plants with multiple chillers . Based on chiller operating data and the energy input requirements

Portfolio-Scale Optimization of Customer Energy Efficiency Incentive and Marketing: Cooperative Research and Development Final Report, CRADA Number CRD-13-535

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brackney, Larry J.

North East utility National Grid (NGrid) is developing a portfolio-scale application of OpenStudio designed to optimize incentive and marketing expenditures for their energy efficiency (EE) programs. NGrid wishes to leverage a combination of geographic information systems (GIS), public records, customer data, and content from the Building Component Library (BCL) to form a JavaScript Object Notation (JSON) input file that is consumed by an OpenStudio-based expert system for automated model generation. A baseline model for each customer building will be automatically tuned using electricity and gas consumption data, and a set of energy conservation measures (ECMs) associated with each NGrid incentivemore » program will be applied to the model. The simulated energy performance and return on investment (ROI) will be compared with customer hurdle rates and available incentives to A) optimize the incentive required to overcome the customer hurdle rate and B) determine if marketing activity associated with the specific ECM is warranted for that particular customer. Repeated across their portfolio, this process will enable NGrid to substantially optimize their marketing and incentive expenditures, targeting those customers that will likely adopt and benefit from specific EE programs.« less

A Learning Framework for Control-Oriented Modeling of Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rubio-Herrero, Javier; Chandan, Vikas; Siegel, Charles M.

Buildings consume a significant amount of energy worldwide. Several building optimization and control use cases require models of energy consumption which are control oriented, have high predictive capability, imposes minimal data pre-processing requirements, and have the ability to be adapted continuously to account for changing conditions as new data becomes available. Data driven modeling techniques, that have been investigated so far, while promising in the context of buildings, have been unable to simultaneously satisfy all the requirements mentioned above. In this context, deep learning techniques such as Recurrent Neural Networks (RNNs) hold promise, empowered by advanced computational capabilities and bigmore » data opportunities. In this paper, we propose a deep learning based methodology for the development of control oriented models for building energy management and test in on data from a real building. Results show that the proposed methodology outperforms other data driven modeling techniques significantly. We perform a detailed analysis of the proposed methodology along dimensions such as topology, sensitivity, and downsampling. Lastly, we conclude by envisioning a building analytics suite empowered by the proposed deep framework, that can drive several use cases related to building energy management.« less

Cost optimization for buildings with hybrid ventilation systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ji, Kun; Lu, Yan

A method including: computing a total cost for a first zone in a building, wherein the total cost is equal to an actual energy cost of the first zone plus a thermal discomfort cost of the first zone; and heuristically optimizing the total cost to identify temperature setpoints for a mechanical heating/cooling system and a start time and an end time of the mechanical heating/cooling system, based on external weather data and occupancy data of the first zone.

Analyzing the Efficiency of Introduction of the Intermittent Heating Mode

NASA Astrophysics Data System (ADS)

Anisimova, E.; Shcherbak, A.

2017-11-01

The efficiency of introduction of an optimal intermittent heating mode for a service center building in Chelyabinsk is estimated. The optimal intermittent heating mode ensures heat energy saving while maintaining the required microclimate parameters. The graphical dependencies of the amount of heat energy saving on the heat retention of the building and the outdoor air temperature are shown. The fundamental formulas which were the basis for calculating the periods of cooling, warming and expenditures of heat energy for the two heating modes are given. The literature on the issue is reviewed, the main points, advantages and disadvantages in the works of both Russian and foreign authors are revealed. The calculation was carried out in compliance with the modern state standards and regulatory documents. The capital costs of a system construction with an intermittent heating mode are determined.

Algorithmic design for 3D printing at building scale

DOE PAGES

Guerguis, Maged; Eikevik, Leif; Obendorf, Andrew; ...

2017-01-01

Here, this paper addresses the use of algorithmic design paired with additive manufacturing and their potential impact on architectural design and fabrication of a full-sized building, as demonstrated with the AMIE project. AMIE (Additive Manufacturing and Integrated Energy) was collaboration to 3d print a building and vehicle. Both the car and building were designed to generate, store and share energy in an effort to reduce or eliminate reliability on the power grid. This paper is intended to outline our methodology in successfully designing for these innovative strategies, with a focus on the use of computational design tools as a catalystmore » for design optimization, integrated project delivery, rapid prototyping and fabrication of building elements using additive manufacturing.« less

Algorithmic design for 3D printing at building scale

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guerguis, Maged; Eikevik, Leif; Obendorf, Andrew

Here, this paper addresses the use of algorithmic design paired with additive manufacturing and their potential impact on architectural design and fabrication of a full-sized building, as demonstrated with the AMIE project. AMIE (Additive Manufacturing and Integrated Energy) was collaboration to 3d print a building and vehicle. Both the car and building were designed to generate, store and share energy in an effort to reduce or eliminate reliability on the power grid. This paper is intended to outline our methodology in successfully designing for these innovative strategies, with a focus on the use of computational design tools as a catalystmore » for design optimization, integrated project delivery, rapid prototyping and fabrication of building elements using additive manufacturing.« less

Achieving 50% Energy Savings in New Schools, Advanced Energy Design Guides: K-12 Schools (Brochure)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This fact sheet summarizes recommendations for designing elementary, middle, and high school buildings that will result in 50% less energy use than conventional new schools built to minimum code requirements. The recommendations are drawn from the Advanced Energy Design Guide for K-12 School Buildings, an ASHRAE publication that provides comprehensive recommendations for designing low-energy-use school buildings (see sidebar). Designed as a stand-alone document, this fact sheet provides key principles and a set of prescriptive design recommendations appropriate for smaller schools with insufficient budgets to fully implement best practices for integrated design and optimized performance. The recommendations have undergone a thoroughmore » analysis and review process through ASHRAE, and have been deemed the best combination of measures to achieve 50% savings in the greatest number of schools.« less

Efficient and Robust Optimization for Building Energy Simulation

PubMed Central

Pourarian, Shokouh; Kearsley, Anthony; Wen, Jin; Pertzborn, Amanda

2016-01-01

Efficiently, robustly and accurately solving large sets of structured, non-linear algebraic and differential equations is one of the most computationally expensive steps in the dynamic simulation of building energy systems. Here, the efficiency, robustness and accuracy of two commonly employed solution methods are compared. The comparison is conducted using the HVACSIM+ software package, a component based building system simulation tool. The HVACSIM+ software presently employs Powell’s Hybrid method to solve systems of nonlinear algebraic equations that model the dynamics of energy states and interactions within buildings. It is shown here that the Powell’s method does not always converge to a solution. Since a myriad of other numerical methods are available, the question arises as to which method is most appropriate for building energy simulation. This paper finds considerable computational benefits result from replacing the Powell’s Hybrid method solver in HVACSIM+ with a solver more appropriate for the challenges particular to numerical simulations of buildings. Evidence is provided that a variant of the Levenberg-Marquardt solver has superior accuracy and robustness compared to the Powell’s Hybrid method presently used in HVACSIM+. PMID:27325907

Efficient and Robust Optimization for Building Energy Simulation.

PubMed

Pourarian, Shokouh; Kearsley, Anthony; Wen, Jin; Pertzborn, Amanda

2016-06-15

Efficiently, robustly and accurately solving large sets of structured, non-linear algebraic and differential equations is one of the most computationally expensive steps in the dynamic simulation of building energy systems. Here, the efficiency, robustness and accuracy of two commonly employed solution methods are compared. The comparison is conducted using the HVACSIM+ software package, a component based building system simulation tool. The HVACSIM+ software presently employs Powell's Hybrid method to solve systems of nonlinear algebraic equations that model the dynamics of energy states and interactions within buildings. It is shown here that the Powell's method does not always converge to a solution. Since a myriad of other numerical methods are available, the question arises as to which method is most appropriate for building energy simulation. This paper finds considerable computational benefits result from replacing the Powell's Hybrid method solver in HVACSIM+ with a solver more appropriate for the challenges particular to numerical simulations of buildings. Evidence is provided that a variant of the Levenberg-Marquardt solver has superior accuracy and robustness compared to the Powell's Hybrid method presently used in HVACSIM+.

Residential Indoor Temperature Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Booten, Chuck; Robertson, Joseph; Christensen, Dane

2017-04-07

In this study, we are adding to the body of knowledge around answering the question: What are good assumptions for HVAC set points in U.S. homes? We collected and analyzed indoor temperature data from US homes using funding from the U.S. Department of Energy's Building America (BA) program, due to the program's reliance on accurate energy simulation of homes. Simulations are used to set Building America goals, predict the impact of new building techniques and technologies, inform research objectives, evaluate home performance, optimize efficiency packages to meet savings goals, customize savings approaches to specific climate zones, and myriad other uses.

Distributed Energy Resource Optimization Using a Software as Service (SaaS) Approach at the University of California, Davis Campus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stadler, Michael; Marnay, Chris; Donadee, Jon

2011-02-06

Together with OSIsoft LLC as its private sector partner and matching sponsor, the Lawrence Berkeley National Laboratory (Berkeley Lab) won an FY09 Technology Commercialization Fund (TCF) grant from the U.S. Department of Energy. The goal of the project is to commercialize Berkeley Lab's optimizing program, the Distributed Energy Resources Customer Adoption Model (DER-CAM) using a software as a service (SaaS) model with OSIsoft as its first non-scientific user. OSIsoft could in turn provide optimization capability to its software clients. In this way, energy efficiency and/or carbon minimizing strategies could be made readily available to commercial and industrial facilities. Specialized versionsmore » of DER-CAM dedicated to solving OSIsoft's customer problems have been set up on a server at Berkeley Lab. The objective of DER-CAM is to minimize the cost of technology adoption and operation or carbon emissions, or combinations thereof. DER-CAM determines which technologies should be installed and operated based on specific site load, price information, and performance data for available equipment options. An established user of OSIsoft's PI software suite, the University of California, Davis (UCD), was selected as a demonstration site for this project. UCD's participation in the project is driven by its motivation to reduce its carbon emissions. The campus currently buys electricity economically through the Western Area Power Administration (WAPA). The campus does not therefore face compelling cost incentives to improve the efficiency of its operations, but is nonetheless motivated to lower the carbon footprint of its buildings. Berkeley Lab attempted to demonstrate a scenario wherein UCD is forced to purchase electricity on a standard time-of-use tariff from Pacific Gas and Electric (PG&E), which is a concern to Facilities staff. Additionally, DER-CAM has been set up to consider the variability of carbon emissions throughout the day and seasons. Two distinct analyses of value to UCD are possible using this approach. First, optimal investment choices for buildings under the two alternative objectives can be derived. Second, a week-ahead building operations forecaster has been written that executes DER-CAM to find an optimal operating schedule for buildings given their expected building energy services requirements, electricity prices, and local weather. As part of its matching contribution, OSIsoft provided a full implementation of PI and a server to install it on at Berkeley Lab. Using the PItoPI protocol, this gives Berkeley Lab researchers direct access to UCD's PI data base. However, this arrangement is in itself inadequate for performing optimizations. Additional data not included in UCD's PI database would be needed and the campus was not able to provide this information. This report details the process, results, and lessons learned of this commercialization project.« less

Energy efficient model based algorithm for control of building HVAC systems.

PubMed

Kirubakaran, V; Sahu, Chinmay; Radhakrishnan, T K; Sivakumaran, N

2015-11-01

Energy efficient designs are receiving increasing attention in various fields of engineering. Heating ventilation and air conditioning (HVAC) control system designs involve improved energy usage with an acceptable relaxation in thermal comfort. In this paper, real time data from a building HVAC system provided by BuildingLAB is considered. A resistor-capacitor (RC) framework for representing thermal dynamics of the building is estimated using particle swarm optimization (PSO) algorithm. With objective costs as thermal comfort (deviation of room temperature from required temperature) and energy measure (Ecm) explicit MPC design for this building model is executed based on its state space representation of the supply water temperature (input)/room temperature (output) dynamics. The controllers are subjected to servo tracking and external disturbance (ambient temperature) is provided from the real time data during closed loop control. The control strategies are ported on a PIC32mx series microcontroller platform. The building model is implemented in MATLAB and hardware in loop (HIL) testing of the strategies is executed over a USB port. Results indicate that compared to traditional proportional integral (PI) controllers, the explicit MPC's improve both energy efficiency and thermal comfort significantly. Copyright © 2015 Elsevier Inc. All rights reserved.

Achieving Actionable Results from Available Inputs: Metamodels Take Building Energy Simulations One Step Further

DOE Office of Scientific and Technical Information (OSTI.GOV)

Horsey, Henry; Fleming, Katherine; Ball, Brian

Modeling commercial building energy usage can be a difficult and time-consuming task. The increasing prevalence of optimization algorithms provides one path for reducing the time and difficulty. Many use cases remain, however, where information regarding whole-building energy usage is valuable, but the time and expertise required to run and post-process a large number of building energy simulations is intractable. A relatively underutilized option to accurately estimate building energy consumption in real time is to pre-compute large datasets of potential building energy models, and use the set of results to quickly and efficiently provide highly accurate data. This process is calledmore » metamodeling. In this paper, two case studies are presented demonstrating the successful applications of metamodeling using the open-source OpenStudio Analysis Framework. The first case study involves the U.S. Department of Energy's Asset Score Tool, specifically the Preview Asset Score Tool, which is designed to give nontechnical users a near-instantaneous estimated range of expected results based on building system-level inputs. The second case study involves estimating the potential demand response capabilities of retail buildings in Colorado. The metamodel developed in this second application not only allows for estimation of a single building's expected performance, but also can be combined with public data to estimate the aggregate DR potential across various geographic (county and state) scales. In both case studies, the unique advantages of pre-computation allow building energy models to take the place of topdown actuarial evaluations. This paper ends by exploring the benefits of using metamodels and then examines the cost-effectiveness of this approach.« less

Autonomous Energy Grids: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kroposki, Benjamin D; Dall-Anese, Emiliano; Bernstein, Andrey

With much higher levels of distributed energy resources - variable generation, energy storage, and controllable loads just to mention a few - being deployed into power systems, the data deluge from pervasive metering of energy grids, and the shaping of multi-level ancillary-service markets, current frameworks to monitoring, controlling, and optimizing large-scale energy systems are becoming increasingly inadequate. This position paper outlines the concept of 'Autonomous Energy Grids' (AEGs) - systems that are supported by a scalable, reconfigurable, and self-organizing information and control infrastructure, can be extremely secure and resilient (self-healing), and self-optimize themselves in real-time for economic and reliable performancemore » while systematically integrating energy in all forms. AEGs rely on scalable, self-configuring cellular building blocks that ensure that each 'cell' can self-optimize when isolated from a larger grid as well as partaking in the optimal operation of a larger grid when interconnected. To realize this vision, this paper describes the concepts and key research directions in the broad domains of optimization theory, control theory, big-data analytics, and complex system modeling that will be necessary to realize the AEG vision.« less

Indoor thermal environment, air exchange rates, and carbon dioxide concentrations before and after energy retro fits in Finnish and Lithuanian multi-family buildings.

PubMed

Leivo, Virpi; Prasauskas, Tadas; Du, Liuliu; Turunen, Mari; Kiviste, Mihkel; Aaltonen, Anu; Martuzevicius, Dainius; Haverinen-Shaughnessy, Ulla

2018-04-15

Impacts of energy retrofits on indoor thermal environment, i.e. temperature (T) and relative humidity (RH), as well as ventilation rates and carbon dioxide (CO 2 ) concentrations, were assessed in 46 Finnish and 20 Lithuanian multi-family buildings, including 39 retrofitted case buildings in Finland and 15 in Lithuania (the remaining buildings were control buildings with no retrofits). In the Finnish buildings, high indoor T along with low RH levels was commonly observed both before and after the retrofits. Ventilation rates (l/s per person) were higher after the retrofits in buildings with mechanical exhaust ventilation than the corresponding values before the retrofits. Measured CO 2 levels were low in vast majority of buildings. In Lithuania, average indoor T levels were low before the retrofits and there was a significant increase in the average T after the retrofits. In addition, average ventilation rate was lower and CO 2 levels were higher after the retrofits in the case buildings (N=15), both in apartments with natural and mixed ventilation. Based on the results, assessment of thermal conditions and ventilation rates after energy retrofits is crucial for optimal indoor environmental quality and energy use. Copyright © 2017 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawrence, Thomas M.; Boudreau, Marie-Claude; Helsen, Lieve

Recent advances in information and communications technology (ICT) have initiated development of a smart electrical grid and smart buildings. Buildings consume a large portion of the total electricity production worldwide, and to fully develop a smart grid they must be integrated with that grid. Buildings can now be 'prosumers' on the grid (both producers and consumers), and the continued growth of distributed renewable energy generation is raising new challenges in terms of grid stability over various time scales. Buildings can contribute to grid stability by managing their overall electrical demand in response to current conditions. Facility managers must balance demandmore » response requests by grid operators with energy needed to maintain smooth building operations. For example, maintaining thermal comfort within an occupied building requires energy and, thus an optimized solution balancing energy use with indoor environmental quality (adequate thermal comfort, lighting, etc.) is needed. Successful integration of buildings and their systems with the grid also requires interoperable data exchange. However, the adoption and integration of newer control and communication technologies into buildings can be problematic with older legacy HVAC and building control systems. Public policy and economic structures have not kept up with the technical developments that have given rise to the budding smart grid, and further developments are needed in both technical and non-technical areas.« less

Austro-Hungarian Public Building Refurbishment and Energy Efficiency Measures - A Case Study on a Public Building in Sarajevo

NASA Astrophysics Data System (ADS)

Salihbegović, Amira; Čaušević, Amir; Rustempašić, Nerman; Avdić, Dženis; Smajlović, Esad

2017-10-01

Among other pieces of architectural historical heritage in Sarajevo, and Bosnia-Herzegovina in general, the Austro-Hungarian architecture has preserved its original architectural, artistic and engineering characteristics. Both residential and public representative urban blocks, streets and squares are of distinguishable ambience in the architectural and urban image of the city and are testifying about our architectural past. A number of buildings is valorised and protected by law in terms of their architectural, artistic and historical value. In addition, these buildings have a distinct functional, ambiental, historical, and even aesthetical value. To make them last longer, refurbishment of these buildings is challenging and presents potential and multiple benefits for the city, and beyond. Refurbishing built environment through functional reorganizing, redesign and energy efficiency measures applications could result in prolonged longevity, architectural identity preservation and interior comfort improvement. Besides, implemented measures for energy efficiency, through the refurbishment process, should optimize the needs for energy consumption in treated buildings. This paper defines options in comfort improvements and redesign, without implying risks to the building longevity, analyses interventions and energy efficiency measures which would enable potential energy saving assessment in the refurbishment process of masonry buildings. This paper also discusses the different techniques that can be adopted for conservation and preservation of historical masonry buildings from the Austro-Hungarian period dealing with energy efficiency. The works were preceded by historical research and on-site investigations. This paper describes a methodology to quantify their vulnerability. A scheme of structural retrofitting is suggested following the research conducted. Revitalization of the building consisted in the reconstruction of the old building structure, creating the inner courtyard and covering it with a glass roof.

Internal heat gain from different light sources in the building lighting systems

NASA Astrophysics Data System (ADS)

Suszanowicz, Dariusz

2017-10-01

EU directives and the Construction Law have for some time required investors to report the energy consumption of buildings, and this has indeed caused low energy consumption buildings to proliferate. Of particular interest, internal heat gains from installed lighting affect the final energy consumption for heating of both public and residential buildings. This article presents the results of analyses of the electricity consumption and the luminous flux and the heat flux emitted by different types of light sources used in buildings. Incandescent light, halogen, compact fluorescent bulbs, and LED bulbs from various manufacturers were individually placed in a closed and isolated chamber, and the parameters for their functioning under identical conditions were recorded. The heat flux emitted by 1 W nominal power of each light source was determined. Based on the study results, the empirical coefficients of heat emission and energy efficiency ratios for different types of lighting sources (dependent lamp power and the light output) were designated. In the heat balance of the building, the designated rates allow for precise determination of the internal heat gains coming from lighting systems using various light sources and also enable optimization of lighting systems of buildings that are used in different ways.

Study on the Control Strategy of Ground Source Heat Pump of Complex Buildings

NASA Astrophysics Data System (ADS)

Dandan, Zhang; Wei, Li; Siyi, Tang

2018-05-01

The complex building group is a building group which integrates residential, business and office. Study on the operation of buried tube heat exchanger (BHE) with 30%, 50%, 70% and 100% occupancy rate by numerical simulation under the condition of full operation of the business and office, the optimal operation control strategy of a hybrid ground-source heat pump (HGSHP) system with different occupancy rates can be obtained. The results show that: at low occupancy rate the optimal operation control of the heat pump system is to use the cooling tower in the valley load period (June and September) and the heat absorption of the buried tube in winter; While at high occupancy rates, opening the cooling tower when the temperature of the outlet of the BHE is 2 degrees centigrade higher than the temperature of the wet bulb at the corresponding time is the optimal operating strategy. This paper is based on the annual energy consumption and optimization of soil temperature rise, which has an important guideline value for the design and operation of HGSHP system in complex buildings.

Intelligent systems installed in building of research centre for research purposes

NASA Astrophysics Data System (ADS)

Matusov, Jozef; Mokry, Marian; Kolkova, Zuzana; Sedivy, Stefan

2016-06-01

The attractiveness of intelligent buildings is nowadays directly connected with higher level of comfort and also the economic mode of consumption energy for heating, cooling and the total consumption of electricity for electric devices. The technologies of intelligent buildings compared with conventional solutions allow dynamic optimization in real time and make it easy for operational message. The basic division of functionality in horizontal direction is possible divide in to two areas such as Economical sophisticated residential care about the comfort of people in the building and Security features. The paper deals with description of intelligent systems which has a building of Research Centre. The building has installed the latest technology for utilization of renewable energy and also latest systems of controlling and driving all devices which contribute for economy operation by achieving the highest thermal comfort and overall safety.

Hybrid Model-Based and Data-Driven Fault Detection and Diagnostics for Commercial Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frank, Stephen; Heaney, Michael; Jin, Xin

Commercial buildings often experience faults that produce undesirable behavior in building systems. Building faults waste energy, decrease occupants' comfort, and increase operating costs. Automated fault detection and diagnosis (FDD) tools for buildings help building owners discover and identify the root causes of faults in building systems, equipment, and controls. Proper implementation of FDD has the potential to simultaneously improve comfort, reduce energy use, and narrow the gap between actual and optimal building performance. However, conventional rule-based FDD requires expensive instrumentation and valuable engineering labor, which limit deployment opportunities. This paper presents a hybrid, automated FDD approach that combines building energymore » models and statistical learning tools to detect and diagnose faults noninvasively, using minimal sensors, with little customization. We compare and contrast the performance of several hybrid FDD algorithms for a small security building. Our results indicate that the algorithms can detect and diagnose several common faults, but more work is required to reduce false positive rates and improve diagnosis accuracy.« less

Hybrid Model-Based and Data-Driven Fault Detection and Diagnostics for Commercial Buildings: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frank, Stephen; Heaney, Michael; Jin, Xin

Commercial buildings often experience faults that produce undesirable behavior in building systems. Building faults waste energy, decrease occupants' comfort, and increase operating costs. Automated fault detection and diagnosis (FDD) tools for buildings help building owners discover and identify the root causes of faults in building systems, equipment, and controls. Proper implementation of FDD has the potential to simultaneously improve comfort, reduce energy use, and narrow the gap between actual and optimal building performance. However, conventional rule-based FDD requires expensive instrumentation and valuable engineering labor, which limit deployment opportunities. This paper presents a hybrid, automated FDD approach that combines building energymore » models and statistical learning tools to detect and diagnose faults noninvasively, using minimal sensors, with little customization. We compare and contrast the performance of several hybrid FDD algorithms for a small security building. Our results indicate that the algorithms can detect and diagnose several common faults, but more work is required to reduce false positive rates and improve diagnosis accuracy.« less

Peak reduction for commercial buildings using energy storage

NASA Astrophysics Data System (ADS)

Chua, K. H.; Lim, Y. S.; Morris, S.

2017-11-01

Battery-based energy storage has emerged as a cost-effective solution for peak reduction due to the decrement of battery’s price. In this study, a battery-based energy storage system is developed and implemented to achieve an optimal peak reduction for commercial customers with the limited energy capacity of the energy storage. The energy storage system is formed by three bi-directional power converter rated at 5 kVA and a battery bank with capacity of 64 kWh. Three control algorithms, namely fixed-threshold, adaptive-threshold, and fuzzy-based control algorithms have been developed and implemented into the energy storage system in a campus building. The control algorithms are evaluated and compared under different load conditions. The overall experimental results show that the fuzzy-based controller is the most effective algorithm among the three controllers in peak reduction. The fuzzy-based control algorithm is capable of incorporating a priori qualitative knowledge and expertise about the load characteristic of the buildings as well as the useable energy without over-discharging the batteries.

Progress Towards Highly Efficient Windows for Zero—Energy Buildings

NASA Astrophysics Data System (ADS)

Selkowitz, Stephen

2008-09-01

Energy efficient windows could save 4 quads/year, with an additional 1 quad/year gain from daylighting in commercial buildings. This corresponds to 13% of energy used by US buildings and 5% of all energy used by the US. The technical potential is thus very large and the economic potential is slowly becoming a reality. This paper describes the progress in energy efficient windows that employ low-emissivity glazing, electrochromic switchable coatings and other novel materials. Dynamic systems are being developed that use sensors and controls to modulate daylighting and shading contributions in response to occupancy, comfort and energy needs. Improving the energy performance of windows involves physics in a variety of application: optics, heat transfer, materials science and applied engineering. Technical solutions must also be compatible with national policy, codes and standards, economics, business practice and investment, real and perceived risks, comfort, health, safety, productivity, amenities, and occupant preference and values. The challenge is to optimize energy performance by understanding and reinforcing the synergetic coupling between these many issues.

Smart building temperature control using occupant feedback

NASA Astrophysics Data System (ADS)

Gupta, Santosh K.

This work was motivated by the problem of computing optimal commonly-agreeable thermal settings in spaces with multiple occupants. In this work we propose algorithms that take into account each occupant's preferences along with the thermal correlations between different zones in a building, to arrive at optimal thermal settings for all zones of the building in a coordinated manner. In the first part of this work we incorporate active occupant feedback to minimize aggregate user discomfort and total energy cost. User feedback is used to estimate the users comfort range, taking into account possible inaccuracies in the feedback. The control algorithm takes the energy cost into account, trading it off optimally with the aggregate user discomfort. A lumped heat transfer model based on thermal resistance and capacitance is used to model a multi-zone building. We provide a stability analysis and establish convergence of the proposed solution to a desired temperature that minimizes the sum of energy cost and aggregate user discomfort. However, for convergence to the optimal, sufficient separation between the user feedback frequency and the dynamics of the system is necessary; otherwise, the user feedback provided do not correctly reflect the effect of current control input value on user discomfort. The algorithm is further extended using singular perturbation theory to determine the minimum time between successive user feedback solicitations. Under sufficient time scale separation, we establish convergence of the proposed solution. Simulation study and experimental runs on the Watervliet based test facility demonstrates performance of the algorithm. In the second part we develop a consensus algorithm for attaining a common temperature set-point that is agreeable to all occupants of a zone in a typical multi-occupant space. The information on the comfort range functions is indeed held privately by each occupant. Using occupant differentiated dynamically adjusted prices as feedback signals, we propose a distributed solution, which ensures that a consensus is attained among all occupants upon convergence, irrespective of their temperature preferences being in coherence or conflicting. Occupants are only assumed to be rational, in that they choose their own temperature set-points so as to minimize their individual energy cost plus discomfort. We use Alternating Direction Method of Multipliers ( ADMM) to solve our consensus problem. We further establish the convergence of the proposed algorithm to the optimal thermal set point values that minimize the sum of the energy cost and the aggregate discomfort of all occupants in a multi-zone building. For simulating our consensus algorithm we use realistic building parameters based on the Watervliet test facility. The simulation study based on real world building parameters establish the validity of our theoretical model and provide insights on the dynamics of the system with a mobile user population. In the third part we present a game-theoretic (auction) mechanism, that requires occupants to "purchase" their individualized comfort levels beyond what is provided by default by the building operator. The comfort pricing policy, derived as an extension of Vickrey-Clarke-Groves (VCG) pricing, ensures incentive-compatibility of the mechanism, i.e., an occupant acting in self-interest cannot benefit from declaring their comfort function untruthfully, irrespective of the choices made by other occupants. The declared (or estimated) occupant comfort ranges (functions) are then utilized by the building operator---along with the energy cost information---to set the environment controls to optimally balance the aggregate discomfort of the occupants and the energy cost of the building operator. We use realistic building model and parameters based on our test facility to demonstrate the convergence of the actual temperatures in different zones to the desired temperatures, and provide insight to the pricing structure necessary for truthful comfort feedback from the occupants. Finally, we present an end-to-end framework designed for enabling occupant feedback collection and incorporating the feedback data towards energy efficient operation of a building. We have designed a mobile application that occupants can use on their smart phones to provide their thermal preference feedback. When relaying the occupant feedback to the central server the mobile application also uses indoor localization techniques to tie the occupant preference to their current thermal zone. Texas Instruments sensortags are used for real time zonal temperature readings. The mobile application relays the occupant preference along with the location to a central server that also hosts our learning algorithm to learn the environment and using occupant feedback calculates the optimal temperature set point. The entire process is triggered upon change of occupancy, environmental conditions, and or occupant preference. The learning algorithm is scheduled to run at regular intervals to respond dynamically to environmental and occupancy changes. We describe results from experimental studies in two different settings: a single family residential home setting and in a university based laboratory space setting. (Abstract shortened by UMI.).

Energy-efficient building design in cold climates: Schools as a case study

NASA Astrophysics Data System (ADS)

Rangel Ruiz, Rocio

Buildings account for great amounts of greenhouse gas emissions. In terms of energy, buildings account for one third of the total amount of energy used in the country every year! Schools account for 14 percent of the energy used annually in commercial and institutional buildings. Further, schools are one of the most commonly constructed building types in Canada and spaces such as classrooms are often duplicated. This makes them preferred candidates for the research that was undertaken where energy-efficient solutions that can be transferred to different school designs were derived. Throughout the study, the Commercial Building Incentive Program (CBIP) was used as a benchmark. The objectives of the study were to demonstrate energy-efficient concepts, provide a case study to evaluate solutions, develop typological models and provide an understanding of the innovation process. The technological and societal aspects of the energy-efficient design were addressed. With respect to the technological aspects, the first step was the analysis of conventional design using a school in Calgary as a case study. The optimization of conventional design was undertaken using computer modeling to identify best practice solutions. Aspects that were included in the studies were lighting design, envelope characteristics, HVAC systems and building plant systems. The inclusion of passive design included the analysis of daylighting and natural ventilation. Computer modeling was used to assess daylighting in classrooms with unilateral and bilateral daylighting. Illuminance levels, glare and light distribution were evaluated. The study of natural ventilation was undertaken using literature review. Airflow and outdoor temperatures were the focus to identify solutions that could be incorporated into the design of classrooms. It was concluded that achieving excellence in energy efficiency in schools could be achieved using readily available technologies. Energy savings of up to 63 percent better than Canada's Model National Energy Code for Buildings (MNECB) reference case and utility cost savings of 30,000 (on a 50,000 annual cost) were achieved through conventional design optimization. Additional energy savings of three percent and utility cost savings of $7,000 were seen when passive strategies were included in the design. With respect to the societal aspects, an exploratory research study was undertaken to examine innovation. Architects and energy consultants were interviewed. All design professionals included in the study had participated in projects approved for a grant under CBIP. The purpose of the study was to identify drivers and barriers to energy efficiency. The study demonstrated that external and internal innovation pressures have a significant effect on whether or not the technology is adopted. Suggestions for reducing barriers and further promoting energy efficiency are discussed in this thesis. It is expected that the research will not only aid designers in assessing projects with regard to local priorities, but will also provide building guidelines that serve as tools for the development of the Canadian energy compliance for CO2 emissions.

Center for the Built Environment: Research on Building HVAC Systems

Science.gov Websites

, and lessons learned. Underfloor Air Distribution (UFAD) Cooling Airflow Design Tool Developing simplified design tools for optimization of underfloor systems. Underfloor Air Distribution (UFAD) Cost Near-ZNE Buildings Setpoint Energy Savings Calculator UFAD Case Studies UFAD Cooling Design Tool UFAD

Optimal Solar PV Arrays Integration for Distributed Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Omitaomu, Olufemi A; Li, Xueping

2012-01-01

Solar photovoltaic (PV) systems hold great potential for distributed energy generation by installing PV panels on rooftops of residential and commercial buildings. Yet challenges arise along with the variability and non-dispatchability of the PV systems that affect the stability of the grid and the economics of the PV system. This paper investigates the integration of PV arrays for distributed generation applications by identifying a combination of buildings that will maximize solar energy output and minimize system variability. Particularly, we propose mean-variance optimization models to choose suitable rooftops for PV integration based on Markowitz mean-variance portfolio selection model. We further introducemore » quantity and cardinality constraints to result in a mixed integer quadratic programming problem. Case studies based on real data are presented. An efficient frontier is obtained for sample data that allows decision makers to choose a desired solar energy generation level with a comfortable variability tolerance level. Sensitivity analysis is conducted to show the tradeoffs between solar PV energy generation potential and variability.« less

Mining Building Energy Management System Data Using Fuzzy Anomaly Detection and Linguistic Descriptions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dumidu Wijayasekara; Ondrej Linda; Milos Manic

Building Energy Management Systems (BEMSs) are essential components of modern buildings that utilize digital control technologies to minimize energy consumption while maintaining high levels of occupant comfort. However, BEMSs can only achieve these energy savings when properly tuned and controlled. Since indoor environment is dependent on uncertain criteria such as weather, occupancy, and thermal state, performance of BEMS can be sub-optimal at times. Unfortunately, the complexity of BEMS control mechanism, the large amount of data available and inter-relations between the data can make identifying these sub-optimal behaviors difficult. This paper proposes a novel Fuzzy Anomaly Detection and Linguistic Description (Fuzzy-ADLD)more » based method for improving the understandability of BEMS behavior for improved state-awareness. The presented method is composed of two main parts: 1) detection of anomalous BEMS behavior and 2) linguistic representation of BEMS behavior. The first part utilizes modified nearest neighbor clustering algorithm and fuzzy logic rule extraction technique to build a model of normal BEMS behavior. The second part of the presented method computes the most relevant linguistic description of the identified anomalies. The presented Fuzzy-ADLD method was applied to real-world BEMS system and compared against a traditional alarm based BEMS. In six different scenarios, the Fuzzy-ADLD method identified anomalous behavior either as fast as or faster (an hour or more), that the alarm based BEMS. In addition, the Fuzzy-ADLD method identified cases that were missed by the alarm based system, demonstrating potential for increased state-awareness of abnormal building behavior.« less

Ten questions concerning future buildings beyond zero energy and carbon neutrality

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Na; Phelan, Patrick E.; Gonzalez, Jorge

2017-07-01

Architects, planners, and building scientists have been at the forefront of envisioning a future built environment for centuries. However, fragmental views that emphasize one facet of the built environment, such as energy, environment, or groundbreaking technologies, often do not achieve expected outcomes. Buildings are responsible for approximately one-third of worldwide carbon emissions and account for over 40% of primary energy consumption in the U.S. In addition to achieving the ambitious goal of reducing building greenhouse gas emissions by 75% by 2050, buildings must improve their functionality and performance to meet current and future human, societal, and environmental needs in amore » changing world. In this article, we introduce a new framework to guide potential evolution of the building stock in the next century, based on greenhouse gas emissions as the common thread to investigate the potential implications of new design paradigms, innovative operational strategies, and disruptive technologies. This framework emphasizes integration of multidisciplinary knowledge, scalability for mainstream buildings, and proactive approaches considering constraints and unknowns. The framework integrates the interrelated aspects of the built environment through a series of quantitative metrics that aim to improve environmental outcomes while optimizing building performance to achieve healthy, adaptive, and productive buildings.« less

BEopt-CA (Ex): A Tool for Optimal Integration of EE, DR and PV in Existing California Homes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christensen, Craig; Horowitz, Scott; Maguire, Jeff

2014-04-01

This project targeted the development of a software tool, BEopt-CA (Ex) (Building Energy Optimization Tool for California Existing Homes), that aims to facilitate balanced integration of energy efficiency (EE), demand response (DR), and photovoltaics (PV) in the residential retrofit1 market. The intent is to provide utility program managers and contractors in the EE/DR/PV marketplace with a means of balancing the integration of EE, DR, and PV

Distributed Energy Resources On-Site Optimization for Commercial Buildings with Electric and Thermal Storage Technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lacommare, Kristina S H; Stadler, Michael; Aki, Hirohisa

The addition of storage technologies such as flow batteries, conventional batteries, and heat storage can improve the economic as well as environmental attractiveness of on-site generation (e.g., PV, fuel cells, reciprocating engines or microturbines operating with or without CHP) and contribute to enhanced demand response. In order to examine the impact of storage technologies on demand response and carbon emissions, a microgrid's distributed energy resources (DER) adoption problem is formulated as a mixed-integer linear program that has the minimization of annual energy costs as its objective function. By implementing this approach in the General Algebraic Modeling System (GAMS), the problemmore » is solved for a given test year at representative customer sites, such as schools and nursing homes, to obtain not only the level of technology investment, but also the optimal hourly operating schedules. This paper focuses on analysis of storage technologies in DER optimization on a building level, with example applications for commercial buildings. Preliminary analysis indicates that storage technologies respond effectively to time-varying electricity prices, i.e., by charging batteries during periods of low electricity prices and discharging them during peak hours. The results also indicate that storage technologies significantly alter the residual load profile, which can contribute to lower carbon emissions depending on the test site, its load profile, and its adopted DER technologies.« less

Modeling of thermal storage systems in MILP distributed energy resource models

DOE PAGES

Steen, David; Stadler, Michael; Cardoso, Gonçalo; ...

2014-08-04

Thermal energy storage (TES) and distributed generation technologies, such as combined heat and power (CHP) or photovoltaics (PV), can be used to reduce energy costs and decrease CO 2 emissions from buildings by shifting energy consumption to times with less emissions and/or lower energy prices. To determine the feasibility of investing in TES in combination with other distributed energy resources (DER), mixed integer linear programming (MILP) can be used. Such a MILP model is the well-established Distributed Energy Resources Customer Adoption Model (DER-CAM); however, it currently uses only a simplified TES model to guarantee linearity and short run-times. Loss calculationsmore » are based only on the energy contained in the storage. This paper presents a new DER-CAM TES model that allows improved tracking of losses based on ambient and storage temperatures, and compares results with the previous version. A multi-layer TES model is introduced that retains linearity and avoids creating an endogenous optimization problem. The improved model increases the accuracy of the estimated storage losses and enables use of heat pumps for low temperature storage charging. Ultimately,results indicate that the previous model overestimates the attractiveness of TES investments for cases without possibility to invest in heat pumps and underestimates it for some locations when heat pumps are allowed. Despite a variation in optimal technology selection between the two models, the objective function value stays quite stable, illustrating the complexity of optimal DER sizing problems in buildings and microgrids.« less

Protein structure modeling for CASP10 by multiple layers of global optimization.

PubMed

Joo, Keehyoung; Lee, Juyong; Sim, Sangjin; Lee, Sun Young; Lee, Kiho; Heo, Seungryong; Lee, In-Ho; Lee, Sung Jong; Lee, Jooyoung

2014-02-01

In the template-based modeling (TBM) category of CASP10 experiment, we introduced a new protocol called protein modeling system (PMS) to generate accurate protein structures in terms of side-chains as well as backbone trace. In the new protocol, a global optimization algorithm, called conformational space annealing (CSA), is applied to the three layers of TBM procedure: multiple sequence-structure alignment, 3D chain building, and side-chain re-modeling. For 3D chain building, we developed a new energy function which includes new distance restraint terms of Lorentzian type (derived from multiple templates), and new energy terms that combine (physical) energy terms such as dynamic fragment assembly (DFA) energy, DFIRE statistical potential energy, hydrogen bonding term, etc. These physical energy terms are expected to guide the structure modeling especially for loop regions where no template structures are available. In addition, we developed a new quality assessment method based on random forest machine learning algorithm to screen templates, multiple alignments, and final models. For TBM targets of CASP10, we find that, due to the combination of three stages of CSA global optimizations and quality assessment, the modeling accuracy of PMS improves at each additional stage of the protocol. It is especially noteworthy that the side-chains of the final PMS models are far more accurate than the models in the intermediate steps. Copyright © 2013 Wiley Periodicals, Inc.

Design Concepts for Optimum Energy Use in HVAC Systems.

ERIC Educational Resources Information Center

Electric Energy Association, New York, NY.

Much of the innovative work in the design and application of heating, ventilating, and air conditioning (HVAC) systems is concentrated on improving the cost effectiveness of such systems through optimizing energy use. One approach to the problem is to reduce a building's HVAC energy demands by designing it for lower heat gains and losses in the…

New Whole-House Solutions Case Study: Testing Ductless Heat Pumps in High-Performance Affordable Housing, the Woods at Golden Given - Tacoma, Washington

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2015-06-01

The Woods is a 30-home, high- performance, energy efficient sustainable community built by Habitat for Humanity (HFH). With Support from Tacoma Public Utilities, Washington State University (part of the Building America Partnership for Improved Residential Construction) is researching the energy performance of these homes and the ductless heat pumps (DHP) they employ. This project provides Building America with an opportunity to: field test HVAC equipment, ventilation system air flows, building envelope tightness, lighting, appliance, and other input data that are required for preliminary Building Energy Optimization (BEopt™) modeling and ENERGY STAR® field verification; analyze cost data from HFH and othermore » sources related to building-efficiency measures that focus on the DHP/hybrid heating system and heat recovery ventilation system; evaluate the thermal performance and cost benefit of DHP/hybrid heating systems in these homes from the perspective of homeowners; compare the space heating energy consumption of a DHP/electric resistance (ER) hybrid heating system to that of a traditional zonal ER heating system; conduct weekly "flip-flop tests" to compare space heating, temperature, and relative humidity in ER zonal heating mode to DHP/ER mode.« less

An Economic Analysis of Solar Water & Space Heating.

ERIC Educational Resources Information Center

Energy Research and Development Administration, Washington, DC. Div. of Solar Energy.

Solar system designs for 13 cities were optimized so as to minimize the life cycle cost over the assumed 20-year lifetime of the solar energy systems. A number of major assumptions were made regarding the solar system, type and use of building, financial considerations, and economic environment used in the design optimization. Seven optimum…

Experimental data showing the thermal behavior of a flat roof with phase change material.

PubMed

Tokuç, Ayça; Başaran, Tahsin; Yesügey, S Cengiz

2015-12-01

The selection and configuration of building materials for optimal energy efficiency in a building require some assumptions and models for the thermal behavior of the utilized materials. Although the models for many materials can be considered acceptable for simulation and calculation purposes, the work for modeling the real time behavior of phase change materials is still under development. The data given in this article shows the thermal behavior of a flat roof element with a phase change material (PCM) layer. The temperature and energy given to and taken from the building element are reported. In addition the solid-liquid behavior of the PCM is tracked through images. The resulting thermal behavior of the phase change material is discussed and simulated in [1] A. Tokuç, T. Başaran, S.C. Yesügey, An experimental and numerical investigation on the use of phase change materials in building elements: the case of a flat roof in Istanbul, Build. Energy, vol. 102, 2015, pp. 91-104.

Validating Savings Claims of Cold Climate Zero Energy Ready Homes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williamson, J.; Puttagunta, S.

This study was intended to validate actual performance of three ZERHs in the Northeast to energy models created in REM/Rate v14.5 (one of the certified software programs used to generate a HERS Index) and the National Renewable Energy Laboratory’s Building Energy Optimization (BEopt™) v2.3 E+ (a more sophisticated hourly energy simulation software). This report details the validation methods used to analyze energy consumption at each home.

The potential of value management (VM) to improve the consideration of energy efficiency within pre-construction

NASA Astrophysics Data System (ADS)

Tahir, Mohamad Zamhari; Nawi, Mohd Nasrun Mohd; Rajemi, Mohamad Farizal

2016-08-01

Energy demand and consumption in buildings will rise rapidly in the near future because of several social economics factors and this situation occurs not only in developed countries but also in developing countries such as Malaysia. There is demand towards building with energy efficiency features at this time, however most of the current buildings types are still being constructed with conventional designs, thus contribute to inefficient of energy consumption during the operation stage of the building. This paper presents the concept and the application of Value Management (VM) approach and its potential to improve consideration of energy efficiency within pre-construction process. Based on the relevant literatures, VM has provides an efficient and effective delivery system to fulfill the objectives and client's requirements. Generally in this paper, VM is discussed and scrutinized with reference to previous studies to see how these concepts contribute to better optimize the energy consumption in a building by seeking the best value energy efficiency through the design and construction process. This paper will not draw any conclusion but rather a preliminary research to propose the most energy efficiency measures to reliably accomplish a function that will meet the client's needs, desires and expectations. For further research in future, simple quantitative industry survey and VM workshops will be conducted to validate and further improve the research.

Skylight energy performance and design optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arasteh, D.; Johnson, R.; Selkowitz, S.

1984-02-01

Proper skylight utilization can significantly lower energy requirements and peak electrical loads for space conditioning and lighting in commercial buildings. In this study we systematically explore the energy effects of skylight systems in a prototypical office building and examine the savings from daylighting. The DOE-2.1B energy analysis computer program with its newly incorporated daylighting algorithms was used to generate more than 2000 parametric simulations for seven US climates. The parameters varied include skylight-to-roof ratio, shading coefficient, visible transmittance, skylight well light loss, electric lighting power density, roof heat transfer coefficient, and type of electric lighting control. For specific climates wemore » identify roof/skylight characteristics that minimize total energy or peak electrical load requirements.« less

A Petri Net model for distributed energy system

NASA Astrophysics Data System (ADS)

Konopko, Joanna

2015-12-01

Electrical networks need to evolve to become more intelligent, more flexible and less costly. The smart grid is the next generation power energy, uses two-way flows of electricity and information to create a distributed automated energy delivery network. Building a comprehensive smart grid is a challenge for system protection, optimization and energy efficient. Proper modeling and analysis is needed to build an extensive distributed energy system and intelligent electricity infrastructure. In this paper, the whole model of smart grid have been proposed using Generalized Stochastic Petri Nets (GSPN). The simulation of created model is also explored. The simulation of the model has allowed the analysis of how close the behavior of the model is to the usage of the real smart grid.

Annual Energy Savings and Thermal Comfort of Autonomously Heated and Cooled Office Chairs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carmichael, Scott; Booten, Chuck; Robertson, Joseph

Energy use in offices buildings is largely driven by air conditioning demands. But the optimal temperature is not the same for all building occupants, leading to the infamous thermostat war. And many occupants have independently overcome building comfort weaknesses with their own space heaters or fans. NREL tested is a customized office chair that automatically heats and cools the occupant along the seat and chair back according to the occupants' personal preferences. This product is shown to deliver markedly better comfort at room temperatures well above typical office cooling setpoints. Experimental subjects reported satisfaction in these elevated air temperatures, partlymore » because the chair's cooling effect was tuned to their own individual needs. Simulation of the chair in office buildings around the U.S. shows that energy can be saved everywhere, with impacts varying due to the climate. Total building HVAC energy savings exceeded 10% in hot-dry climate zones. Due to high product cost, simple payback for the chair we studied is beyond the expected chair life. We then understood the need to establish cost-performance targets for comfort delivery packages. NREL derived several hypothetical energy/cost/comfort targets for personal comfort product systems. In some climate regions around the U.S., these show the potential for office building HVAC energy savings in excess of 20%. This report documents this research, providing an overview of the research team's methods and results while also identifying areas for future research building upon the findings.« less

Corporate Delivery of a Global Smart Buildings Program

DOE PAGES

Fernandes, Samuel; Granderson, Jessica; Singla, Rupam; ...

2017-11-22

Buildings account for about 40 percent of the total energy consumption in the U.S. and emit approximately one third of greenhouse gas emissions. But they also offer tremendous potential for achieving significant greenhouse gas reductions with the right savings strategies. With an increasing amount of data from buildings and advanced computational and analytical abilities, buildings can be made “smart” to optimize energy consumption and occupant comfort. Smart buildings are often characterized as having a high degree of data and system integration, connectivity and control, as well as the advanced use of data analytics. These “smarts” can enable up to 10–20%more » savings in a building, and help ensure that they persist over time. In 2009, Microsoft Corporation launched the Energy-Smart Buildings (ESB) program with a vision to improve building operations services, security and accessibility in services, and new tenant applications and services that improve productivity and optimize energy use. The ESB program focused on fault diagnostics, advanced analytics and new organizational processes and practices to support their operational integration. In addition to the ESB program, Microsoft undertook capital improvement projects that made effective use of a utility incentive program and lab consolidations over the same duration. The ESB program began with a pilot at Microsoft's Puget Sound campus that identified significant savings of up to 6–10% in the 13 pilot buildings. The success of the pilot led to a global deployment of the program. Between 2009 and 2015, there was a 23.7% reduction in annual electricity consumption (kWh) at the Puget Sound campus with 18.5% of that resulting from the ESB and lab consolidations. This article provides the results of research conducted to assess the best-practice strategies that Microsoft implemented to achieve these savings, including the fault diagnostic routines that are the foundation of the ESB program and organizational change management practices. It also presents the process that was adopted to scale the ESB program globally. We conclude with recommendations for how these successes can be generalized and replicated by other corporate enterprises.« less

Corporate Delivery of a Global Smart Buildings Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fernandes, Samuel; Granderson, Jessica; Singla, Rupam

Buildings account for about 40 percent of the total energy consumption in the U.S. and emit approximately one third of greenhouse gas emissions. But they also offer tremendous potential for achieving significant greenhouse gas reductions with the right savings strategies. With an increasing amount of data from buildings and advanced computational and analytical abilities, buildings can be made “smart” to optimize energy consumption and occupant comfort. Smart buildings are often characterized as having a high degree of data and system integration, connectivity and control, as well as the advanced use of data analytics. These “smarts” can enable up to 10–20%more » savings in a building, and help ensure that they persist over time. In 2009, Microsoft Corporation launched the Energy-Smart Buildings (ESB) program with a vision to improve building operations services, security and accessibility in services, and new tenant applications and services that improve productivity and optimize energy use. The ESB program focused on fault diagnostics, advanced analytics and new organizational processes and practices to support their operational integration. In addition to the ESB program, Microsoft undertook capital improvement projects that made effective use of a utility incentive program and lab consolidations over the same duration. The ESB program began with a pilot at Microsoft's Puget Sound campus that identified significant savings of up to 6–10% in the 13 pilot buildings. The success of the pilot led to a global deployment of the program. Between 2009 and 2015, there was a 23.7% reduction in annual electricity consumption (kWh) at the Puget Sound campus with 18.5% of that resulting from the ESB and lab consolidations. This article provides the results of research conducted to assess the best-practice strategies that Microsoft implemented to achieve these savings, including the fault diagnostic routines that are the foundation of the ESB program and organizational change management practices. It also presents the process that was adopted to scale the ESB program globally. We conclude with recommendations for how these successes can be generalized and replicated by other corporate enterprises.« less

Near Zero Energy House (NZEH) Design Optimization to Improve Life Cycle Cost Performance Using Genetic Algorithm

NASA Astrophysics Data System (ADS)

Latief, Y.; Berawi, M. A.; Koesalamwardi, A. B.; Supriadi, L. S. R.

2018-03-01

Near Zero Energy House (NZEH) is a housing building that provides energy efficiency by using renewable energy technologies and passive house design. Currently, the costs for NZEH are quite expensive due to the high costs of the equipment and materials for solar panel, insulation, fenestration and other renewable energy technology. Therefore, a study to obtain the optimum design of a NZEH is necessary. The aim of the optimum design is achieving an economical life cycle cost performance of the NZEH. One of the optimization methods that could be utilized is Genetic Algorithm. It provides the method to obtain the optimum design based on the combinations of NZEH variable designs. This paper discusses the study to identify the optimum design of a NZEH that provides an optimum life cycle cost performance using Genetic Algorithm. In this study, an experiment through extensive design simulations of a one-level house model was conducted. As a result, the study provide the optimum design from combinations of NZEH variable designs, which are building orientation, window to wall ratio, and glazing types that would maximize the energy generated by photovoltaic panel. Hence, the design would support an optimum life cycle cost performance of the house.

Expert Meeting: Optimized Heating Systems Using Condensing Boilers and Baseboard Convectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arena, L.

2013-01-01

On August 11, 2011, in Denver, CO, a Building America Expert Meeting was held in conjunction with the Building America Residential Energy Efficiency Technical Update Meeting, to review and discuss results and future plans for research to improve the performance of hydronic heating systems using condensing boilers and baseboard convectors. A meeting objective was to provide an opportunity for other Building America teams and industry experts to provide feedback and specific suggestions for the planned research.

Operative air temperature data for different measures applied on a building envelope in warm climate.

PubMed

Baglivo, Cristina; Congedo, Paolo Maria

2018-04-01

Several technical combinations have been evaluated in order to design high energy performance buildings for the warm climate. The analysis has been developed in several steps, avoiding the use of HVAC systems. The methodological approach of this study is based on a sequential search technique and it is shown on the paper entitled "Envelope Design Optimization by Thermal Modeling of a Building in a Warm Climate" [1]. The Operative Air Temperature trends (TOP), for each combination, have been plotted through a dynamic simulation performed using the software TRNSYS 17 (a transient system simulation program, University of Wisconsin, Solar Energy Laboratory, USA, 2010). Starting from the simplest building configuration consisting of 9 rooms (equal-sized modules of 5 × 5 m 2 ), the different building components are sequentially evaluated until the envelope design is optimized. The aim of this study is to perform a step-by-step simulation, simplifying as much as possible the model without making additional variables that can modify their performances. Walls, slab-on-ground floor, roof, shading and windows are among the simulated building components. The results are shown for each combination and evaluated for Brindisi, a city in southern Italy having 1083 degrees day, belonging to the national climatic zone C. The data show the trends of the TOP for each measure applied in the case study for a total of 17 combinations divided into eight steps.

Parametric Analysis of Energy Consumption in Army Buildings by the Building Loads Analysis and System Thermodynamics (BLAST) Computer Program.

DTIC Science & Technology

1980-08-01

orientation, and HVAC systems have on three Army buildings in five different climatic regions. f Optimization of EnerV Usage in Military Facilities...The clinic’s environment is maintained by a multizone air-handling unit served by its own boiler and chiller . The building was modeled with 30... setpoints for the space temperature. This type of throttling range allows the heating system to control around a throttling range of 67 to 69oF (19 to 200

Experimental Demonstration of Frequency Regulation by Commercial Buildings – Part I: Modeling and Hierarchical Control Design

DOE PAGES

Vrettos, Evangelos; Kara, Emre C.; MacDonald, Jason; ...

2016-11-15

Here, this paper is the first part of a two-part series in which we present results from one of the first worldwide experimental demonstrations of frequency regulation in a commercial building test facility. We demonstrate that commercial buildings can track a frequency regulation signal with high accuracy and minimal occupant discomfort in a realistic environment. In addition, we show that buildings can determine the reserve capacity and baseline power a priori, and identify the optimal tradeoff between frequency regulation and energy efficiency.

REopt Lite Web Tool Evaluates Photovoltaics and Battery Storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Building on the success of the REopt renewable energy integration and optimization platform, NREL has developed a free, publicly available web version of REopt called REopt Lite. REopt Lite evaluates the economics of grid-connected photovoltaics (PV) and battery storage at a site. It allows building owners to identify the system sizes and battery dispatch strategy that minimize their life cycle cost of energy. This web tool also estimates the amount of time a PV and storage system can sustain the site's critical load during a grid outage.

An Extensible Sensing and Control Platform for Building Energy Management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rowe, Anthony; Berges, Mario; Martin, Christopher

2016-04-03

The goal of this project is to develop Mortar.io, an open-source BAS platform designed to simplify data collection, archiving, event scheduling and coordination of cross-system interactions. Mortar.io is optimized for (1) robustness to network outages, (2) ease of installation using plug-and-play and (3) scalable support for small to large buildings and campuses.

Spatial optimization for decentralized non-potable water reuse

NASA Astrophysics Data System (ADS)

Kavvada, Olga; Nelson, Kara L.; Horvath, Arpad

2018-06-01

Decentralization has the potential to reduce the scale of the piped distribution network needed to enable non-potable water reuse (NPR) in urban areas by producing recycled water closer to its point of use. However, tradeoffs exist between the economies of scale of treatment facilities and the size of the conveyance infrastructure, including energy for upgradient distribution of recycled water. To adequately capture the impacts from distribution pipes and pumping requirements, site-specific conditions must be accounted for. In this study, a generalized framework (a heuristic modeling approach using geospatial algorithms) is developed that estimates the financial cost, the energy use, and the greenhouse gas emissions associated with NPR (for toilet flushing) as a function of scale of treatment and conveyance networks with the goal of determining the optimal degree of decentralization. A decision-support platform is developed to assess and visualize NPR system designs considering topography, economies of scale, and building size. The platform can be used for scenario development to explore the optimal system size based on the layout of current or new buildings. The model also promotes technology innovation by facilitating the systems-level comparison of options to lower costs, improve energy efficiency, and lower greenhouse gas emissions.

Optimal quantum operations at zero energy cost

NASA Astrophysics Data System (ADS)

Chiribella, Giulio; Yang, Yuxiang

2017-08-01

Quantum technologies are developing powerful tools to generate and manipulate coherent superpositions of different energy levels. Envisaging a new generation of energy-efficient quantum devices, here we explore how coherence can be manipulated without exchanging energy with the surrounding environment. We start from the task of converting a coherent superposition of energy eigenstates into another. We identify the optimal energy-preserving operations, both in the deterministic and in the probabilistic scenario. We then design a recursive protocol, wherein a branching sequence of energy-preserving filters increases the probability of success while reaching maximum fidelity at each iteration. Building on the recursive protocol, we construct efficient approximations of the optimal fidelity-probability trade-off, by taking coherent superpositions of the different branches generated by probabilistic filtering. The benefits of this construction are illustrated in applications to quantum metrology, quantum cloning, coherent state amplification, and ancilla-driven computation. Finally, we extend our results to transitions where the input state is generally mixed and we apply our findings to the task of purifying quantum coherence.

BIM cost analysis of transport infrastructure projects

NASA Astrophysics Data System (ADS)

Volkov, Andrey; Chelyshkov, Pavel; Grossman, Y.; Khromenkova, A.

2017-10-01

The article describes the method of analysis of the energy costs of transport infrastructure objects using BIM software. The paper consideres several options of orientation of a building using SketchUp and IES VE software programs. These options allow to choose the best direction of the building facades. Particular attention is given to a distribution of a temperature field in a cross-section of the wall according to the calculation made in the ELCUT software. The issues related to calculation of solar radiation penetration into a building and selection of translucent structures are considered in the paper. The article presents data on building codes relating to the transport sector, on the basis of which the calculations were made. The author emphasizes that BIM-programs should be implemented and used in order to optimize a thermal behavior of a building and increase its energy efficiency using climatic data.

Optimal Technology Investment and Operation in Zero-Net-Energy Buildings with Demand Response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stadler , Michael; Siddiqui, Afzal; Marnay, Chris

The US Department of Energy has launched the Zero-Net-Energy (ZNE) Commercial Building Initiative (CBI) in order to develop commercial buildings that produce as much energy as they use. Its objective is to make these buildings marketable by 2025 such that they minimize their energy use through cutting-edge energy-efficient technologies and meet their remaining energy needs through on-site renewable energy generation. We examine how such buildings may be implemented within the context of a cost- or carbon-minimizing microgrid that is able to adopt and operate various technologies, such as photovoltaic (PV) on-site generation, heat exchangers, solar thermal collectors, absorption chillers, andmore » passive / demand-response technologies. We use a mixed-integer linear program (MILP) that has a multi-criteria objective function: the minimization of a weighted average of the building's annual energy costs and carbon / CO2 emissions. The MILP's constraints ensure energy balance and capacity limits. In addition, constraining the building's energy consumed to equal its energy exports enables us to explore how energy sales and demand-response measures may enable compliance with the CBI. Using a nursing home in northern California and New York with existing tariff rates and technology data, we find that a ZNE building requires ample PV capacity installed to ensure electricity sales during the day. This is complemented by investment in energy-efficient combined heat and power equipment, while occasional demand response shaves energy consumption. A large amount of storage is also adopted, which may be impractical. Nevertheless, it shows the nature of the solutions and costs necessary to achieve ZNE. For comparison, we analyze a nursing home facility in New York to examine the effects of a flatter tariff structure and different load profiles. It has trouble reaching ZNE status and its load reductions as well as efficiency measures need to be more effective than those in the CA case. Finally, we illustrate that the multi-criteria frontier that considers costs and carbon emissions in the presence of demand response dominates the one without it.« less

Night ventilation control strategies in office buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhaojun; Yi, Lingli; Gao, Fusheng

2009-10-15

In moderate climates night ventilation is an effective and energy-efficient approach to improve the indoor thermal environment for office buildings during the summer months, especially for heavyweight construction. However, is night ventilation a suitable strategy for office buildings with lightweight construction located in cold climates? In order to answer this question, the whole energy-consumption analysis software EnergyPlus was used to simulate the indoor thermal environment and energy consumption in typical office buildings with night mechanical ventilation in three cities in northern China. The summer outdoor climate data was analyzed, and three typical design days were chosen. The most important factorsmore » influencing night ventilation performance such as ventilation rates, ventilation duration, building mass and climatic conditions were evaluated. When night ventilation operation time is closer to active cooling time, the efficiency of night ventilation is higher. With night ventilation rate of 10 ach, the mean radiant temperature of the indoor surface decreased by up to 3.9 C. The longer the duration of operation, the more efficient the night ventilation strategy becomes. The control strategies for three locations are given in the paper. Based on the optimized strategies, the operation consumption and fees are calculated. The results show that more energy is saved in office buildings cooled by a night ventilation system in northern China than ones that do not employ this strategy. (author)« less

A Petri Net model for distributed energy system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Konopko, Joanna

2015-12-31

Electrical networks need to evolve to become more intelligent, more flexible and less costly. The smart grid is the next generation power energy, uses two-way flows of electricity and information to create a distributed automated energy delivery network. Building a comprehensive smart grid is a challenge for system protection, optimization and energy efficient. Proper modeling and analysis is needed to build an extensive distributed energy system and intelligent electricity infrastructure. In this paper, the whole model of smart grid have been proposed using Generalized Stochastic Petri Nets (GSPN). The simulation of created model is also explored. The simulation of themore » model has allowed the analysis of how close the behavior of the model is to the usage of the real smart grid.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cutler, Dylan; Frank, Stephen; Slovensky, Michelle

Rich, well-organized building performance and energy consumption data enable a host of analytic capabilities for building owners and operators, from basic energy benchmarking to detailed fault detection and system optimization. Unfortunately, data integration for building control systems is challenging and costly in any setting. Large portfolios of buildings--campuses, cities, and corporate portfolios--experience these integration challenges most acutely. These large portfolios often have a wide array of control systems, including multiple vendors and nonstandard communication protocols. They typically have complex information technology (IT) networks and cybersecurity requirements and may integrate distributed energy resources into their infrastructure. Although the challenges are significant,more » the integration of control system data has the potential to provide proportionally greater value for these organizations through portfolio-scale analytics, comprehensive demand management, and asset performance visibility. As a large research campus, the National Renewable Energy Laboratory (NREL) experiences significant data integration challenges. To meet them, NREL has developed an architecture for effective data collection, integration, and analysis, providing a comprehensive view of data integration based on functional layers. The architecture is being evaluated on the NREL campus through deployment of three pilot implementations.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

By working with builder partners on test homes, researchers from the U.S. Department of Energy's Building America program can vet whole-house building strategies and avoid potential unintended consequences of implementing untested solution packages on a production scale. To support this research, Building America team Consortium for Advanced Residential Buildings (CARB) partnered with Preferred Builders Inc. on a high-performance test home in Old Greenwich, Connecticut. The philosophy and science behind the 2,700 ft2 "Performance House" was based on the premise that homes should be safe, healthy, comfortable, durable, efficient, and adaptable to the needs of homeowners. The technologies and strategies usedmore » in the "Performance House" were best practices rather than cutting edge, with a focus on simplicity in construction, maintenance, and operation. Achieving 30% source energy savings compared with a home built to the 2009 International Energy Conservation Code in the cold climate zone requires that nearly all components and systems be optimized. Careful planning and design are critical. The end result was a DOE Challenge Home that achieved a Home Energy Rating System (HERS) Index Score of 20 (43 without photovoltaics [PV]).« less

Supporting Building Portfolio Investment and Policy Decision Making through an Integrated Building Utility Data Platform

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aziz, Azizan; Lasternas, Bertrand; Alschuler, Elena

The American Recovery and Reinvestment Act stimulus funding of 2009 for smart grid projects resulted in the tripling of smart meters deployment. In 2012, the Green Button initiative provided utility customers with access to their real-time1 energy usage. The availability of finely granular data provides an enormous potential for energy data analytics and energy benchmarking. The sheer volume of time-series utility data from a large number of buildings also poses challenges in data collection, quality control, and database management for rigorous and meaningful analyses. In this paper, we will describe a building portfolio-level data analytics tool for operational optimization, businessmore » investment and policy assessment using 15-minute to monthly intervals utility data. The analytics tool is developed on top of the U.S. Department of Energy’s Standard Energy Efficiency Data (SEED) platform, an open source software application that manages energy performance data of large groups of buildings. To support the significantly large volume of granular interval data, we integrated a parallel time-series database to the existing relational database. The time-series database improves on the current utility data input, focusing on real-time data collection, storage, analytics and data quality control. The fully integrated data platform supports APIs for utility apps development by third party software developers. These apps will provide actionable intelligence for building owners and facilities managers. Unlike a commercial system, this platform is an open source platform funded by the U.S. Government, accessible to the public, researchers and other developers, to support initiatives in reducing building energy consumption.« less

Diffusion of Energy Efficient Technology in Commercial Buildings: An Analysis of the Commercial Building Partnerships Program

NASA Astrophysics Data System (ADS)

Antonopoulos, Chrissi Argyro

This study presents findings from survey and interview data investigating replication of green building measures by Commercial Building Partnership (CBP) partners that worked directly with the Pacific Northwest National Laboratory (PNNL). PNNL partnered directly with 12 organizations on new and retrofit construction projects, which represented approximately 28 percent of the entire U.S. Department of Energy (DOE) CBP program. Through a feedback survey mechanism, along with personal interviews, quantitative and qualitative data were gathered relating to replication efforts by each organization. These data were analyzed to provide insight into two primary research areas: 1) CBP partners' replication efforts of green building approaches used in the CBP project to the rest of the organization's building portfolio, and, 2) the market potential for technology diffusion into the total U.S. commercial building stock, as a direct result of the CBP program. The first area of this research focused specifically on replication efforts underway or planned by each CBP program participant. The second area of this research develops a diffusion of innovations model to analyze potential broad market impacts of the CBP program on the commercial building industry in the United States. Findings from this study provided insight into motivations and objectives CBP partners had for program participation. Factors that impact replication include motivation, organizational structure and objectives firms have for implementation of energy efficient technologies. Comparing these factors between different CBP partners revealed patterns in motivation for constructing energy efficient buildings, along with better insight into market trends for green building practices. The optimized approach to the CBP program allows partners to develop green building parameters that fit the specific uses of their building, resulting in greater motivation for replication. In addition, the diffusion model developed for this analysis indicates that this method of market prediction may be used to adequately capture cumulative construction metrics for a whole-building analysis as opposed to individual energy efficiency measures used in green building.

Preliminary Design of a Solar Photovoltaic Array for Net-Zero Energy Buildings at NASA Langley

NASA Technical Reports Server (NTRS)

Cole, Stuart K.; DeYoung, Russell J.

2012-01-01

An investigation was conducted to evaluate photovoltaic (solar electric systems) systems for a single building at NASA Langley as a representative case for alternative sustainable power generation. Building 1250 in the Science Directorate is comprised of office and laboratory space, and currently uses approximately 250,000 kW/month of electrical power with a projected use of 200,000 kW/month with additional conservation measures. The installation would be applied towards a goal for having Building 1250 classified as a net-zero energy building as it would produce as much energy as it uses over the course of a year. Based on the facility s electrical demand, a photovoltaic system and associated hardware were characterized to determine the optimal system, and understand the possible impacts from its deployment. The findings of this investigation reveal that the 1.9 MW photovoltaic electrical system provides favorable and robust results. The solar electric system should supply the needed sustainable power solution especially if operation and maintenance of the system will be considered a significant component of the system deployment.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Katherine H.; Cutler, Dylan S.; Olis, Daniel R.

REopt is a techno-economic decision support model used to optimize energy systems for buildings, campuses, communities, and microgrids. The primary application of the model is for optimizing the integration and operation of behind-the-meter energy assets. This report provides an overview of the model, including its capabilities and typical applications; inputs and outputs; economic calculations; technology descriptions; and model parameters, variables, and equations. The model is highly flexible, and is continually evolving to meet the needs of each analysis. Therefore, this report is not an exhaustive description of all capabilities, but rather a summary of the core components of the model.

Deep Energy Retrofit Guidance for the Building America Solutions Center

DOE Office of Scientific and Technical Information (OSTI.GOV)

Less, Brennan; Walker, Iain

2015-01-01

The U.S. DOE Building America program has established a research agenda targeting market-relevant strategies to achieve 40% reductions in existing home energy use by 2030. Deep Energy Retrofits (DERs) are part of the strategy to meet and exceed this goal. DERs are projects that create new, valuable assets from existing residences, by bringing homes into alignment with the expectations of the 21st century. Ideally, high energy using, dated homes that are failing to provide adequate modern services to their owners and occupants (e.g., comfortable temperatures, acceptable humidity, clean, healthy), are transformed through comprehensive upgrades to the building envelope, services andmore » miscellaneous loads into next generation high performance homes. These guidance documents provide information to aid in the broader market adoption of DERs. They are intended for inclusion in the online resource the Building America Solutions Center (BASC). This document is an assemblage of multiple entries in the BASC, each of which addresses a specific aspect of Deep Energy Retrofit best practices for projects targeting at least 50% energy reductions. The contents are based upon a review of actual DERs in the U.S., as well as a mixture of engineering judgment, published guidance from DOE research in technologies and DERs, simulations of cost-optimal DERs, Energy Star and Consortium for Energy Efficiency (CEE) product criteria, and energy codes.« less

Economic Analysis and Optimal Sizing for behind-the-meter Battery Storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Di; Kintner-Meyer, Michael CW; Yang, Tao

This paper proposes methods to estimate the potential benefits and determine the optimal energy and power capacity for behind-the-meter BSS. In the proposed method, a linear programming is first formulated only using typical load profiles, energy/demand charge rates, and a set of battery parameters to determine the maximum saving in electric energy cost. The optimization formulation is then adapted to include battery cost as a function of its power and energy capacity in order to capture the trade-off between benefits and cost, and therefore to determine the most economic battery size. Using the proposed methods, economic analysis and optimal sizingmore » have been performed for a few commercial buildings and utility rate structures that are representative of those found in the various regions of the Continental United States. The key factors that affect the economic benefits and optimal size have been identified. The proposed methods and case study results cannot only help commercial and industrial customers or battery vendors to evaluate and size the storage system for behind-the-meter application, but can also assist utilities and policy makers to design electricity rate or subsidies to promote the development of energy storage.« less

Towards a framework for selection of supervisory control for commercial buildings: HVAC system energy efficiency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramachandran, Thiagarajan; Kundu, Soumya; Chen, Yan

This paper develops and utilizes an optimization based framework to investigate the maximal energy efficiency potentially attainable by HVAC system operation in a non-predictive context. Performance is evaluated relative to the existing state of the art set point reset strategies. The expected efficiency increase driven by operation constraints relaxations is evaluated.

Towards a framework for selection of supervisory control for commercial buildings: HVAC system energy efficiency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramachandran, Thiagarajan; Kundu, Soumya; Chen, Yan

This paper develops and utilizes an optimization based framework to investigate the maximal energy efficiency potentially attainable by HVAC system operation in a non-predictive context. Performance is evaluated relative to the existing state of the art set-point reset strategies. The expected efficiency increase driven by operation constraints relaxations is evaluated.

Study on the optimum PCM melting temperature for energy savings in residential buildings worldwide

NASA Astrophysics Data System (ADS)

Saffari, M.; de Gracia, A.; Fernández, C.; Zsembinszki, G.; Cabeza, L. F.

2017-10-01

To maintain comfort conditions in residential buildings along a full year period, the use of active systems is generally required to either supply heating or cooling. The heating and cooling demands strongly depend on the climatic conditions, type of building and occupants’ behaviour. The overall annual energy consumption of the building can be reduced by the use of renewable energy sources and/or passive systems. The use of phase change materials (PCM) as passive systems in buildings enhances the thermal mass of the envelope, and reduces the indoor temperature fluctuations. As a consequence, the overall energy consumption of the building is generally lower as compared to the case when no PCM systems are used. The selection of the PCM melting temperature is a key issue to reduce the energy consumption of the buildings. The main focus of this study is to determine the optimum PCM melting temperature for passive heating and cooling according to different weather conditions. To achieve that, numerical simulations were carried out using EnergyPlus v8.4 coupled with GenOpt® v3.1.1 (a generic optimization software). A multi-family residential apartment was selected from ASHRAE Standard 90.1- 2013 prototype building model, and different climate conditions were considered to determine the optimum melting temperature (in the range from 20ºC to 26ºC) of the PCM contained in gypsum panels. The results confirm that the optimum melting temperature of the PCM strongly depends on the climatic conditions. In general, in cooling dominant climates the optimum PCM temperature is around 26ºC, while in heating dominant climates it is around 20ºC. Furthermore, the results show that an adequate selection of the PCM as passive system in building envelope can provide important energy savings for both heating dominant and cooling dominant regions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mendes, Goncalo; Feng, Wei; Stadler, Michael

The following paper conducts a regional analysis of the U.S. and Chinese buildings? potential for adopting Distributed Energy Resources (DER). The expected economics of DER in 2020-2025 is modeled for a commercial and a multi-family residential building in different climate zones. The optimal building energy economic performance is calculated using the Distributed Energy Resources Customer Adoption Model (DER CAM) which minimizes building energy costs for a typical reference year of operation. Several DER such as combined heat and power (CHP) units, photovoltaics, and battery storage are considered. The results indicate DER have economic and environmental competitiveness potential, especially for commercialmore » buildings in hot and cold climates of both countries. In the U.S., the average expected energy cost savings in commercial buildings from DER CAM?s suggested investments is 17percent, while in Chinese buildings is 12percent. The electricity tariffs structure and prices along with the cost of natural gas, represent important factors in determining adoption of DER, more so than climate. High energy pricing spark spreads lead to increased economic attractiveness of DER. The average emissions reduction in commercial buildings is 19percent in the U.S. as a result of significant investments in PV, whereas in China, it is 20percent and driven by investments in CHP. Keywords: Building Modeling and Simulation, Distributed Energy Resources (DER), Energy Efficiency, Combined Heat and Power (CHP), CO2 emissions 1. Introduction The transition from a centralized and fossil-based energy paradigm towards the decentralization of energy supply and distribution has been a major subject of research over the past two decades. Various concerns have brought the traditional model into question; namely its environmental footprint, its structural inflexibility and inefficiency, and more recently, its inability to maintain acceptable reliability of supply. Under such a troubled setting, distributed energy resources (DER) comprising of small, modular, electrical renewable or fossil-based electricity generation units placed at or near the point of energy consumption, has gained much attention as a viable alternative or addition to the current energy system. In 2010, China consumed about 30percent of its primary energy in the buildings sector, leading the country to pay great attention to DER development and its applications in buildings. During the 11th Five Year Plan (FYP), China has implemented 371 renewable energy building demonstration projects, and 210 photovoltaics (PV) building integration projects. At the end of the 12th FYP, China is targeting renewable energy to provide 10percent of total building energy, and to save 30 metric tons of CO2 equivalents (mtce) of energy with building integrated renewables. China is also planning to implement one thousand natural gas-based distributed cogeneration demonstration projects with energy utilization rates over 70percent in the 12th FYP. All these policy targets require significant DER systems development for building applications. China?s fast urbanization makes building energy efficiency a crucial economic issue; however, only limited studies have been done that examine how to design and select suitable building energy technologies in its different regions. In the U.S., buildings consumed 40percent of the total primary energy in 2010 [1] and it is estimated that about 14 billion m2 of floor space of the existing building stock will be remodeled over the next 30 years. Most building?s renovation work has been on building envelope, lighting and HVAC systems. Although interest has emerged, less attention is being paid to DER for buildings. This context has created opportunities for research, development and progressive deployment of DER, due to its potential to combine the production of power and heat (CHP) near the point of consumption and delivering multiple benefits to customers, such as cost« less

Use of Machine Learning Algorithms to Propose a New Methodology to Conduct, Critique and Validate Urban Scale Building Energy Modeling

NASA Astrophysics Data System (ADS)

Pathak, Maharshi

City administrators and real-estate developers have been setting up rather aggressive energy efficiency targets. This, in turn, has led the building science research groups across the globe to focus on urban scale building performance studies and level of abstraction associated with the simulations of the same. The increasing maturity of the stakeholders towards energy efficiency and creating comfortable working environment has led researchers to develop methodologies and tools for addressing the policy driven interventions whether it's urban level energy systems, buildings' operational optimization or retrofit guidelines. Typically, these large-scale simulations are carried out by grouping buildings based on their design similarities i.e. standardization of the buildings. Such an approach does not necessarily lead to potential working inputs which can make decision-making effective. To address this, a novel approach is proposed in the present study. The principle objective of this study is to propose, to define and evaluate the methodology to utilize machine learning algorithms in defining representative building archetypes for the Stock-level Building Energy Modeling (SBEM) which are based on operational parameter database. The study uses "Phoenix- climate" based CBECS-2012 survey microdata for analysis and validation. Using the database, parameter correlations are studied to understand the relation between input parameters and the energy performance. Contrary to precedence, the study establishes that the energy performance is better explained by the non-linear models. The non-linear behavior is explained by advanced learning algorithms. Based on these algorithms, the buildings at study are grouped into meaningful clusters. The cluster "mediod" (statistically the centroid, meaning building that can be represented as the centroid of the cluster) are established statistically to identify the level of abstraction that is acceptable for the whole building energy simulations and post that the retrofit decision-making. Further, the methodology is validated by conducting Monte-Carlo simulations on 13 key input simulation parameters. The sensitivity analysis of these 13 parameters is utilized to identify the optimum retrofits. From the sample analysis, the envelope parameters are found to be more sensitive towards the EUI of the building and thus retrofit packages should also be directed to maximize the energy usage reduction.

Recovery Act: Training Program Development for Commercial Building Equipment Technicians

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leah Glameyer

The overall goal of this project has been to develop curricula, certification requirements, and accreditation standards for training on energy efficient practices and technologies for commercial building technicians. These training products will advance industry expertise towards net-zero energy commercial building goals and will result in a substantial reduction in energy use. The ultimate objective is to develop a workforce that can bring existing commercial buildings up to their energy performance potential and ensure that new commercial buildings do not fall below their expected optimal level of performance. Commercial building equipment technicians participating in this training program will learn how tomore » best operate commercial buildings to ensure they reach their expected energy performance level. The training is a combination of classroom, online and on-site lessons. The Texas Engineering Extension Service (TEEX) developed curricula using subject matter and adult learning experts to ensure the training meets certification requirements and accreditation standards for training these technicians. The training targets a specific climate zone to meets the needs, specialized expertise, and perspectives of the commercial building equipment technicians in that zone. The combination of efficient operations and advanced design will improve the internal built environment of a commercial building by increasing comfort and safety, while reducing energy use and environmental impact. Properly trained technicians will ensure equipment operates at design specifications. A second impact is a more highly trained workforce that is better equipped to obtain employment. Organizations that contributed to the development of the training program include TEEX and the Texas Engineering Experiment Station (TEES) (both members of The Texas A&M University System). TEES is also a member of the Building Commissioning Association. This report includes a description of the project accomplishments, including the course development phases, tasks associated with each phase, and detailed list of the course materials developed. A summary of each year's activities is also included.« less

Leveraging OpenStudio's Application Programming Interfaces: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Long, N.; Ball, B.; Goldwasser, D.

2013-11-01

OpenStudio development efforts have been focused on providing Application Programming Interfaces (APIs) where users are able to extend OpenStudio without the need to compile the open source libraries. This paper will discuss the basic purposes and functionalities of the core libraries that have been wrapped with APIs including the Building Model, Results Processing, Advanced Analysis, UncertaintyQuantification, and Data Interoperability through Translators. Several building energy modeling applications have been produced using OpenStudio's API and Software Development Kits (SDK) including the United States Department of Energy's Asset ScoreCalculator, a mobile-based audit tool, an energy design assistance reporting protocol, and a portfolio scalemore » incentive optimization analysismethodology. Each of these software applications will be discussed briefly and will describe how the APIs were leveraged for various uses including high-level modeling, data transformations from detailed building audits, error checking/quality assurance of models, and use of high-performance computing for mass simulations.« less

Exploring efficacy of residential energy efficiency programs in Florida

NASA Astrophysics Data System (ADS)

Taylor, Nicholas Wade

Electric utilities, government agencies, and private interests in the U.S. have committed and continue to invest substantial resources in the pursuit of energy efficiency and conservation through demand-side management (DSM) programs. Program investments, and the demand for impact evaluations that accompany them, are projected to grow in coming years due to increased pressure from state-level energy regulation, costs and challenges of building additional production capacity, fuel costs and potential carbon or renewable energy regulation. This dissertation provides detailed analyses of ex-post energy savings from energy efficiency programs in three key sectors of residential buildings: new, single-family, detached homes; retrofits to existing single-family, detached homes; and retrofits to existing multifamily housing units. Each of the energy efficiency programs analyzed resulted in statistically significant energy savings at the full program group level, yet savings for individual participants and participant subgroups were highly variable. Even though savings estimates were statistically greater than zero, those energy savings did not always meet expectations. Results also show that high variability in energy savings among participant groups or subgroups can negatively impact overall program performance and can undermine marketing efforts for future participation. Design, implementation, and continued support of conservation programs based solely on deemed or projected savings is inherently counter to the pursuit of meaningful energy conservation and reductions in greenhouse gas emissions. To fully understand and optimize program impacts, consistent and robust measurement and verification protocols must be instituted in the design phase and maintained over time. Furthermore, marketing for program participation must target those who have the greatest opportunity for savings. In most utility territories it is not possible to gain access to the type of large scale datasets that would facilitate robust program analysis. Along with measuring and optimizing energy conservation programs, utilities should provide public access to historical consumption data. Open access to data, program optimization, consistent measurement and verification and transparency in reported savings are essential to reducing energy use and its associated environmental impacts.

Rapid Deployment of Optimal Control for Building HVAC Systems Using Innovative Software Tools and a Hybrid Heuristic/Model Based Control Approach

DTIC Science & Technology

2017-03-21

for public release; distribution is unlimited 13. SUPPLEMENTARY NOTES None 14. ABSTRACT ESTCP project EW-201409 aimed at demonstrating the benefits ...of innovative software technology for building HV AC systems. These benefits included reduced system energy use and cost as wetl as improved...Control Approach March 2017 This document has been cleared for public release; Distribution Statement A

The perceived value of using BIM for energy simulation

NASA Astrophysics Data System (ADS)

Lewis, Anderson M.

Building Information Modeling (BIM) is becoming an increasingly important tool in the Architectural, Engineering & Construction (AEC) industries. Some of the benefits associated with BIM include but are not limited to cost and time savings through greater trade and design coordination, and more accurate estimating take-offs. BIM is a virtual 3D, parametric design software that allows users to store information of a model within and can be used as a communication platform between project stakeholders. Likewise, energy simulation is an integral tool for predicting and optimizing a building's performance during design. Creating energy models and running energy simulations can be a time consuming activity due to the large number of parameters and assumptions that must be addressed to achieve reasonably accurate results. However, leveraging information imbedded within Building Information Models (BIMs) has the potential to increase accuracy and reduce the amount of time required to run energy simulations and can facilitate continuous energy simulations throughout the design process, thus optimizing building performance. Although some literature exists on how design stakeholders perceive the benefits associated with leveraging BIM for energy simulation, little is known about how perceptions associated with leveraging BIM for energy simulation differ between various green design stakeholder user groups. Through an e-survey instrument, this study seeks to determine how perceptions of using BIMs to inform energy simulation differ among distinct design stakeholder groups, which include BIM-only users, energy simulation-only users and BIM and energy simulation users. Additionally, this study seeks to determine what design stakeholders perceive as the main barriers and benefits of implementing BIM-based energy simulation. Results from this study suggest that little to no correlation exists between green design stakeholders' perceptions of the value associated with using information from BIMs to inform energy simulation and their engagement level with BIM and/or energy simulation. However, green design stakeholder perceptions of the value associated with using information from BIMs to inform energy simulation and their engagement with BIM and/or energy simulation may differ between different user groups (i.e. BIM users only, energy simulation users only, and BIM and energy simulation users). For example, the BIM-only user groups appeared to have a strong positive correlation between the perceptions of the value associated with using information from BIMs to inform energy simulation and their engagement with BIM. Additionally, this study suggests that the top perceived benefits of using BIMs to inform energy simulations among green design stakeholders are: facilitation of communication, reducing of process related costs, and giving users the ability examine more design options. The main perceived barrier of using BIMs to inform energy simulations among green design stakeholders was a lack of BIM standards for model integration with multidisciplinary teams. Results from this study will help readers understand how to better implement BIM-based energy simulation while mitigating barriers and optimizing benefits. Additionally, examining discrepancies between user groups can lead the identification and improvement of shortfalls in current BIM-based energy simulation processes. Understanding how perceptions and engagement levels differ among different software user groups will help in developing a strategies for implementing BIM-based energy simulation that are tailored to each specific user group.

Russian Apartment Building Thermal Response Models for Retrofit Selection and Verification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Armstrong, Peter R.; Dirks, James A.; Reilly, Raymond W.

2000-08-21

The Enterprise Housing Divestiture Project (EHDP) aims to identify cost-effective energy efficiency and conservation measures for Russian apartment buildings and to implement these measures in the entire stock of buildings undergoing divestiture in six cities. Short-term measurements of infiltration and exterior wall heat-loss coefficient were made in the cities of Cheropovets, Orenburg, Petrozavodsk, Ryazan, and Vladimir. Long-term monitoring equipment was installed in six or more buildings in the aforementioned and in the city of Volxhov. The results of these measurements will be used to calibrate models used to select optimal retrofit packages and to verify energy savings. The retrofit categoriesmore » representing the largest technical potential in these buildings are envelope, heat recovery, and heating/hot water system improvements. This paper describes efforts to establish a useful thermal model calibration process. The model structures and analytical methods for obtaining building parameters from time series weather, energy use, and thermal response data are developed. Our experience applying these methods to two, nominally identical 5-story apartment buildings in the city of Ryazan is presented. Building envelope UA?s inferred from measured whole-building thermal response data are compared with UA?s based on window and wall U-values (the latter obtained by ASTM in-situ measurements of 20 wall sections in various Ryazan panel buildings) as well. The UA's obtained by these completely independent measurements differ by less than 10%.« less

Optimal location selection for the installation of urban green roofs considering honeybee habitats along with socio-economic and environmental effects.

PubMed

Gwak, Jae Ha; Lee, Bo Kyeong; Lee, Won Kyung; Sohn, So Young

2017-03-15

This study proposes a new framework for the selection of optimal locations for green roofs to achieve a sustainable urban ecosystem. The proposed framework selects building sites that can maximize the benefits of green roofs, based not only on the socio-economic and environmental benefits to urban residents, but also on the provision of urban foraging sites for honeybees. The framework comprises three steps. First, building candidates for green roofs are selected considering the building type. Second, the selected building candidates are ranked in terms of their expected socio-economic and environmental effects. The benefits of green roofs are improved energy efficiency and air quality, reduction of urban flood risk and infrastructure improvement costs, reuse of storm water, and creation of space for education and leisure. Furthermore, the estimated cost of installing green roofs is also considered. We employ spatial data to determine the expected effects of green roofs on each building unit, because the benefits and costs may vary depending on the location of the building. This is due to the heterogeneous spatial conditions. In the third step, the final building sites are proposed by solving the maximal covering location problem (MCLP) to determine the optimal locations for green roofs as urban honeybee foraging sites. As an illustrative example, we apply the proposed framework in Seoul, Korea. This new framework is expected to contribute to sustainable urban ecosystems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Novel dynamic thermal characterization of multifunctional concretes with microencapsulated phase change materials

NASA Astrophysics Data System (ADS)

Pisello, Anna Laura; Fabiani, Claudia; D'Alessandro, Antonella; Cabeza, Luisa F.; Ubertini, Filippo; Cotana, Franco

2017-04-01

Concrete is widely applied in the construction sector for its reliable mechanical performance, its easiness of use and low costs. It also appears promising for enhancing the thermal-energy behavior of buildings thanks to its capability to be doped with multifunctional fillers. In fact, key studies acknowledged the benefits of thermally insulated concretes for applications in ceilings and walls. At the same time, thermal capacity also represents a key property to be optimized, especially for lightweight constructions. In this view, Thermal-Energy Storage (TES) systems have been recently integrated into building envelopes for increasing thermal inertia. More in detail, numerical experimental investigations showed how Phase Change materials (PCMs), as an acknowledged passive TES strategy, can be effectively included in building envelope, with promising results in terms of thermal buffer potentiality. In particular, this work builds upon previous papers aimed at developing the new PCM-filled concretes for structural applications and optimized thermalenergy efficiency, and it is focused on the development of a new experimental method for testing such composite materials in thermal-energy dynamic conditions simulated in laboratory by exposing samples to environmentally controlled microclimate while measuring thermal conductivity and diffusivity by means of transient plane source techniques. The key findings show how the new composites are able to increasingly delay the thermal wave with increasing the PCM concentration and how the thermal conductivity varies during the course of the phase change, in both melting and solidification processes. The new analysis produces useful findings in proposing an effective method for testing composite materials with adaptive thermal performance, much needed by the scientific community willing to study building envelopes dynamics.

Integrating Geohydrological Models In ATES-Systems Control

NASA Astrophysics Data System (ADS)

Bloemendal, Martin

2015-04-01

1) Purpose. Accomplish optimal and sustainable use of subsurface for Aquifer Thermal Energy Storage (ATES). 2) Scope. A heat pump in combination with an ATES system can efficiently and sustainably provide heating and cooling for user comfort within buildings. ATES systems are popular in moderate climate in which ATES systems are exploited as they are able to save primary energy. While storing warm and cold groundwater, ATES systems occupy a significant amount of the subsurface space, making that the space in the aquifers below cities is becoming scarce [1]. With the rapid growth of the number of ATES systems, the use of the subsurface intensifies, which raises additional questions regarding its sustainability and the long term profitability of the individual systems. In practice considerable difficulties regarding A) the performance of these installations and B) optimal and sustainable use of the subsurface are met. 3) Approach. Recently it was confirmed [2] that ATES systems can be placed closer to each other with limited effect on their energy efficiency. By placing them closer together we introduce the risk of a tragedy of the commons [3]. Therefore it is of importance to know where the warm and cold zones are over time and enable ATES-controllers to use the subsurface optimal and sustainably. From the field of multi agent systems and complex adaptive systems we use approaches and techniques to make an operation and control system that enables to adapt their control not only based on current demand, but also on current aquifer status and expected future demand. We are developing a numerical groundwater model structure which is fed with operational data of different ATES-systems. While doing this we run into challenges and opportunities like; spatial and temporal scale issues, sustaining the storage with balancing thermal storage and extraction at area level, dynamics and relation between hydrological and thermal influence and consequences for spreading of contaminants, using thermal energy storage for "peak-shaving" of wind/solar power production etc.. I will address the following two topics; - Balancing of stored heating and cooling capacity. To sustain an ATES-system heating and cooling capacity storage must more or less balance. Buildings often do not have a similar heating and cooling demand. Placing ATES-well closer to each other offers the opportunity to exchange energy between different buildings in the subsurface to balance heating and cooling capacity. To be able to do so, thorough understanding of the interaction between thermal influence area resulting from highly dynamic and uncertain energy demand from buildings is required. - The hydrological influence area of ATES wells is much bigger than the thermal influence area. Placing wells closer to each other therefor has a significant effect on the mixing of water and spreading of contaminants (which are often present in shallow aquifers under (old) city centers). We use both analytical and numerical approaches to gain insight in patterns of thermal and contaminant spreading and to find solutions in managing these effects. 4) Results and conclusions The subsurface is of crucial importance for intended energy savings. A control system working towards a global optimum for both the subsurface and buildings, instead of a local optimum for an individual building and local ATES will increase the overall efficiency. What is needed for that is insight in the spatial temperature distribution in the subsurface, in combination with adaptive and robust operational rules. We want to prove that a groundwater model simulating active ATES-systems can provide insight in the subsurface temperature distribution to adjust their control strategy in accordance with up-to-date information. Step by step we are solving the problems on this path, I would like to share and discuss my results, solutions and challenges. References [1] Bloemendal, M., Olsthoorn, T., Boons, F., How to achieve optimal and sustainable use of the subsurface for Aquifer Thermal Energy Storage, Energy Policy 66(2014) 104-114 [2] Sommer, W., Valstar, J., Leusbrock, I., Grotenhuis, T., Rijnaarts, H., Optimization and spatial pattern of large-scale aquifer thermal energy storage, Applied Energy 137 (2015) 322-337 [3] Hardin, G., The tragedy of the commons, Science162 (168) 12-13.

Energy efficiency in new museum build: THEpUBLIC

NASA Astrophysics Data System (ADS)

Battle, G.; Yuen, C. H. N.; Zanchetta, M.; D'Cruz, P.

2006-12-01

The project MUSEUMS, awarded the Thermie Grant from the European Commission, has applied and tested new and innovative technologies for optimizing energy efficiency and sustainability in nine retrofitted and new museum buildings in Europe. The project will significantly contribute to the acceptance of innovative and renewable technologies in public buildings by demonstrating that retrofitted and new museum buildings can fully meet architectural, functional, comfort, control and safety requirements as well as achieve total energy savings of over 35% and reduce CO2 emissions by over 50%. THEpUBLIC will be a stunning and modern flagship building containing six storeys, with a total area of 11,000Âm2 of galleries for exhibitions, digital art and hands-on displays. In addition, there will be workspaces, creative spaces, retail opportunities, restaurant facilities, public areas, conference rooms and other multi-function spaces. Initiated by Jubilee Arts, the THEpUBLIC, designed by Alsop Architects, will introduce and engage its 400,000 expected visitors in the principles of energy and the environment through a display of art, education, technology and entertainment in the centre of West Bromwich, Sandwell. It will serve as a catalyst for urban regeneration within Sandwell.Battle McCarthy's key environmental design solutions for THEpUBLIC include natural daylighting, mixed-mode ventilation system with operable windows, low energy and maintenance cost systems, potential for integrating renewable energy collection systems, borehole water systems for cooling and water supply, an intelligent facade system with external shading and natural ventilation and night cooling systems.

Energy-efficient hierarchical processing in the network of wireless intelligent sensors (WISE)

NASA Astrophysics Data System (ADS)

Raskovic, Dejan

Sensor network nodes have benefited from technological advances in the field of wireless communication, processing, and power sources. However, the processing power of microcontrollers is often not sufficient to perform sophisticated processing, while the power requirements of digital signal processing boards or handheld computers are usually too demanding for prolonged system use. We are matching the intrinsic hierarchical nature of many digital signal-processing applications with the natural hierarchy in distributed wireless networks, and building the hierarchical system of wireless intelligent sensors. Our goal is to build a system that will exploit the hierarchical organization to optimize the power consumption and extend battery life for the given time and memory constraints, while providing real-time processing of sensor signals. In addition, we are designing our system to be able to adapt to the current state of the environment, by dynamically changing the algorithm through procedure replacement. This dissertation presents the analysis of hierarchical environment and methods for energy profiling used to evaluate different system design strategies, and to optimize time-effective and energy-efficient processing.

Lawrence Berkeley Laboratory/University of California lighting program overview

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berman, S.

1981-12-01

The objective of the Lighting Program is to assist and work in concert with the lighting community (composed of manufacturers, designers, and users) to achieve a more efficient lighting economy. To implement its objectives, the Lighting Program has been divided into three major categories: technical engineering, buildings applications, and human impacts (impacts on health and vision). The technical program aims to undertake research and development projects that are both long-range and high-risk and which the lighting industry has little interest in pursuing on its own, but from which significant benefits could accrue to both the public and the industry. Themore » building applications program studies the effects that introducing daylighting in commercial buildings has on lighting and cooling electrical energy requirements as well as on peak demand. This program also examines optimization strategies for integrating energy-efficient design, lighting hardware, daylighting, and overall building energy requirements. The impacts program examines relationships between the user and the physical lighting environment, in particular how new energy-efficient technologies relate to human productivity and health. These efforts are interdisciplinary, involving engineering, optometry, and medicine. The program facilities are described and the personnel in the program is identified.« less

Indoor Air Quality: Is Increased Ventilation the Answer?

ERIC Educational Resources Information Center

Hansen, Shirley

1989-01-01

Explains how indoor air quality is affected by pollutants in the air and also by temperature, humidity, and ventilation. Increased ventilation alone seldom solves the "sick building syndrome." Lists ways to improve indoor air quality and optimize energy efficiency. (MLF)

OPTIMIZING GREEN ROOF TECHNOLOGIES IN THE MIDWEST

EPA Science Inventory

Green roofs, while extensively used in Europe, are an emerging technology in the U.S. They have an array of potential benefits (including improved storm water management, increased energy conservation of buildings, reduced urban heat island effects, and extended roof life) ...

Building integration of photovoltaic systems in cold climates

NASA Astrophysics Data System (ADS)

Athienitis, Andreas K.; Candanedo, José A.

2010-06-01

This paper presents some of the research activities on building-integrated photovoltaic (BIPV) systems developed by the Solar and Daylighting Laboratory at Concordia University. BIPV systems offer considerable advantages as compared to stand-alone PV installations. For example, BIPV systems can play a role as essential components of the building envelope. BIPV systems operate as distributed power generators using the most widely available renewable source. Since BIPV systems do not require additional space, they are especially appropriate for urban environments. BIPV/Thermal (BIPV/T) systems may use exterior air to extract useful heat from the PV panels, cooling them and thereby improving their electric performance. The recovered thermal energy can then be used for space heating and domestic hot water (DHW) heating, supporting the utilization of BIVP/T as an appropriate technology for cold climates. BIPV and BIPV/T systems are the subject of several ongoing research and demonstration projects (in both residential and commercial buildings) led by Concordia University. The concept of integrated building design and operation is at the centre of these efforts: BIPV and BIPV/T systems must be treated as part of a comprehensive strategy taking into account energy conservation measures, passive solar design, efficient lighting and HVAC systems, and integration of other renewable energy systems (solar thermal, heat pumps, etc.). Concordia Solar Laboratory performs fundamental research on heat transfer and modeling of BIPV/T systems, numerical and experimental investigations on BIPV and BIPV/T in building energy systems and non-conventional applications (building-attached greenhouses), and the design and optimization of buildings and communities.

Building America Top Innovations 2014 Profile: Cost-Optimized Attic Insulation Solution for Factory-Built Homes

DOE Office of Scientific and Technical Information (OSTI.GOV)

none,

This 2014 Top Innovation profile describes a low-cost, low-tech attic insulation technique developed by the ARIES Building America team with help from Southern Energy Homes and Johns Manville. Increasing attic insulation in manufactured housing has been a significant challenge due to cost, production and transportation constraints. The simplicity of this dense-pack solution to increasing attic insulation R-value promises real hope for widespread industry adoption.

Technology Assessments of High Performance Envelope with Optimized Lighting, Solar Control, and Daylighting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Eleanor S.; Thanachareonkit, Anothai; Touzani, Samir

The objective of this monitored field study was to identify near-term innovative façade technologies for solar control and daylighting with a goal of 20-40% energy use savings below Title 24 2013 in the 30-ft deep perimeter zone near vertical windows within cost and comfort constraints. The targeted market was new or existing commercial office buildings or buildings with similar patterns of use.

Energy Aware Cluster-Based Routing in Flying Ad-Hoc Networks.

PubMed

Aadil, Farhan; Raza, Ali; Khan, Muhammad Fahad; Maqsood, Muazzam; Mehmood, Irfan; Rho, Seungmin

2018-05-03

Flying ad-hoc networks (FANETs) are a very vibrant research area nowadays. They have many military and civil applications. Limited battery energy and the high mobility of micro unmanned aerial vehicles (UAVs) represent their two main problems, i.e., short flight time and inefficient routing. In this paper, we try to address both of these problems by means of efficient clustering. First, we adjust the transmission power of the UAVs by anticipating their operational requirements. Optimal transmission range will have minimum packet loss ratio (PLR) and better link quality, which ultimately save the energy consumed during communication. Second, we use a variant of the K-Means Density clustering algorithm for selection of cluster heads. Optimal cluster heads enhance the cluster lifetime and reduce the routing overhead. The proposed model outperforms the state of the art artificial intelligence techniques such as Ant Colony Optimization-based clustering algorithm and Grey Wolf Optimization-based clustering algorithm. The performance of the proposed algorithm is evaluated in term of number of clusters, cluster building time, cluster lifetime and energy consumption.

Development of a solar-powered residential air conditioner

NASA Technical Reports Server (NTRS)

1975-01-01

The initial objective of the program was the optimization (in terms of cost and performance) of a Rankine cycle mechanical refrigeration system which utilizes thermal energy from a flat solar collector for air conditioning residential buildings. However, feasibility investigations of the adsorption process revealed that a dessicant-type air conditioner offers many significant advantages. As a result, limited efforts were expended toward the optimization of such a system.

Equipment and Energy Usage in a Large Teaching Hospital in Norway.

PubMed

Rohde, Tarald; Martinez, Robert

2015-01-01

This article presents a study of how equipment is used in a Norwegian University hospital and suggests ways to reduce hospital energy consumption. Analysis of energy data from Norway's newest teaching hospital showed that electricity consumption was up to 50% of the whole-building energy consumption. Much of this is due to the increasing energy intensity of hospital-specific equipment. Measured power and reported usage patterns for equipment in the studied departments show daytime energy intensity of equipment at about 28.5 kBTU/ft2 per year (90 kWh/m2 per year), compared to building code standard value of only 14.9 kBTU/ft2 (47 kWh/m2 per year) for hospitals. This article intends to fill gaps in our understanding of how users and their equipment affect the energy balance in hospitals and suggests ways in which designers and equipment suppliers can help optimize energy performance while maintaining quality in the delivery of health services.

Energy Center Structure Optimization by using Smart Technologies in Process Control System

NASA Astrophysics Data System (ADS)

Shilkina, Svetlana V.

2018-03-01

The article deals with practical application of fuzzy logic methods in process control systems. A control object - agroindustrial greenhouse complex, which includes its own energy center - is considered. The paper analyzes object power supply options taking into account connection to external power grids and/or installation of own power generating equipment with various layouts. The main problem of a greenhouse facility basic process is extremely uneven power consumption, which forces to purchase redundant generating equipment idling most of the time, which quite negatively affects project profitability. Energy center structure optimization is largely based on solving the object process control system construction issue. To cut investor’s costs it was proposed to optimize power consumption by building an energy-saving production control system based on a fuzzy logic controller. The developed algorithm of automated process control system functioning ensured more even electric and thermal energy consumption, allowed to propose construction of the object energy center with a smaller number of units due to their more even utilization. As a result, it is shown how practical use of microclimate parameters fuzzy control system during object functioning leads to optimization of agroindustrial complex energy facility structure, which contributes to a significant reduction in object construction and operation costs.

Theoretical and experimental analysis of injection seeding a Q-switched alexandrite laser

NASA Technical Reports Server (NTRS)

Prasad, C. R.; Lee, H. S.; Glesne, T. R.; Monosmith, B.; Schwemmer, G. K.

1991-01-01

Injection seeding is a method for achieving linewidths of less than 500 MHz in the output of broadband, tunable, solid state lasers. Dye lasers, CW and pulsed diode lasers, and other solid state lasers have been used as injection seeders. By optimizing the fundamental laser parameters of pump energy, Q-switched pulse build-up time, injection seed power and mode matching, one can achieve significant improvements in the spectral purity of the Q-switched output. These parameters are incorporated into a simple model for analyzing spectral purity and pulse build-up processes in a Q-switched, injection-seeded laser. Experiments to optimize the relevant parameters of an alexandrite laser show good agreement.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dall'Anese, Emiliano; Baker, Kyri; Summers, Tyler

The paper focuses on distribution systems featuring renewable energy sources and energy storage devices, and develops an optimal power flow (OPF) approach to optimize the system operation in spite of forecasting errors. The proposed method builds on a chance-constrained multi-period AC OPF formulation, where probabilistic constraints are utilized to enforce voltage regulation with a prescribed probability. To enable a computationally affordable solution approach, a convex reformulation of the OPF task is obtained by resorting to i) pertinent linear approximations of the power flow equations, and ii) convex approximations of the chance constraints. Particularly, the approximate chance constraints provide conservative boundsmore » that hold for arbitrary distributions of the forecasting errors. An adaptive optimization strategy is then obtained by embedding the proposed OPF task into a model predictive control framework.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

By working with builder partners on test homes, researchers from the U.S. Department of Energy’s Building America program can vet whole-house building strategies and avoid potential unintended consequences of implementing untested solution packages on a production scale. To support this research, Building America team Consortium for Advanced Residential Buildings (CARB) partnered with Preferred Builders Inc. on a high-performance test home in Old Greenwich, Connecticut. The philosophy and science behind the 2,700 ft2 “Performance House” was based on the premise that homes should be safe, healthy, comfortable, durable, efficient, and adaptable to the needs of homeowners. The technologies and strategies usedmore » in the “Performance House” were best practices rather than cutting edge, with a focus on simplicity in construction, maintenance, and operation. Achieving 30% source energy savings compared with a home built to the 2009 International Energy Conservation Code in the cold climate zone requires that nearly all components and systems be optimized. Careful planning and design are critical. The end result was a DOE Challenge Home that achieved a Home Energy Rating System (HERS) Index Score of 20 (43 without photovoltaics [PV]).« less

On the design of high-rise buildings with a specified level of reliability

NASA Astrophysics Data System (ADS)

Dolganov, Andrey; Kagan, Pavel

2018-03-01

High-rise buildings have a specificity, which significantly distinguishes them from traditional buildings of high-rise and multi-storey buildings. Steel structures in high-rise buildings are advisable to be used in earthquake-proof regions, since steel, due to its plasticity, provides damping of the kinetic energy of seismic impacts. These aspects should be taken into account when choosing a structural scheme of a high-rise building and designing load-bearing structures. Currently, modern regulatory documents do not quantify the reliability of structures. Although the problem of assigning an optimal level of reliability has existed for a long time. The article shows the possibility of designing metal structures of high-rise buildings with specified reliability. Currently, modern regulatory documents do not quantify the reliability of high-rise buildings. Although the problem of assigning an optimal level of reliability has existed for a long time. It is proposed to establish the value of reliability 0.99865 (3σ) for constructions of buildings and structures of a normal level of responsibility in calculations for the first group of limiting states. For increased (construction of high-rise buildings) and reduced levels of responsibility for the provision of load-bearing capacity, it is proposed to assign respectively 0.99997 (4σ) and 0.97725 (2σ). The coefficients of the use of the cross section of a metal beam for different levels of security are given.

An Attempt to Design a Naturally Ventilated Tower in Subtropical Climate of the Developing Country; Pakistan

NASA Astrophysics Data System (ADS)

Sohail, Maha

2017-12-01

A large proportion of the world's population resides in developing countries where there is a lack of rigorous studies in designing energy efficient buildings. This study is a step in designing a naturally ventilated high rise residential building in a tropical climatic context of the developing country, Pakistan. Karachi, the largest city of Pakistan, lies in the subtropical hot desert region with constant high temperature of average 32 °C throughout the summer and no particular winter season. The Design Builder software package is used to design a 25 storey high rise residential building relying primarily on natural ventilation. A final conceptual design is proposed after optimization of massing, geometry, orientation, and improved building envelope design including extensive shading devices in the form of trees. It has been observed that a reduction of 8 °C in indoor ambient temperature is possible to achieve with passive measures and use of night time ventilation. A fully naturally ventilated building can reduce the energy consumption for cooling and heating by 96 % compared to a building using air conditioning systems.

Optimal Power Flow for Distribution Systems under Uncertain Forecasts: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dall'Anese, Emiliano; Baker, Kyri; Summers, Tyler

2016-12-01

The paper focuses on distribution systems featuring renewable energy sources and energy storage devices, and develops an optimal power flow (OPF) approach to optimize the system operation in spite of forecasting errors. The proposed method builds on a chance-constrained multi-period AC OPF formulation, where probabilistic constraints are utilized to enforce voltage regulation with a prescribed probability. To enable a computationally affordable solution approach, a convex reformulation of the OPF task is obtained by resorting to i) pertinent linear approximations of the power flow equations, and ii) convex approximations of the chance constraints. Particularly, the approximate chance constraints provide conservative boundsmore » that hold for arbitrary distributions of the forecasting errors. An adaptive optimization strategy is then obtained by embedding the proposed OPF task into a model predictive control framework.« less

Development of robust building energy demand-side control strategy under uncertainty

NASA Astrophysics Data System (ADS)

Kim, Sean Hay

The potential of carbon emission regulations applied to an individual building will encourage building owners to purchase utility-provided green power or to employ onsite renewable energy generation. As both cases are based on intermittent renewable energy sources, demand side control is a fundamental precondition for maximizing the effectiveness of using renewable energy sources. Such control leads to a reduction in peak demand and/or in energy demand variability, therefore, such reduction in the demand profile eventually enhances the efficiency of an erratic supply of renewable energy. The combined operation of active thermal energy storage and passive building thermal mass has shown substantial improvement in demand-side control performance when compared to current state-of-the-art demand-side control measures. Specifically, "model-based" optimal control for this operation has the potential to significantly increase performance and bring economic advantages. However, due to the uncertainty in certain operating conditions in the field its control effectiveness could be diminished and/or seriously damaged, which results in poor performance. This dissertation pursues improvements of current demand-side controls under uncertainty by proposing a robust supervisory demand-side control strategy that is designed to be immune from uncertainty and perform consistently under uncertain conditions. Uniqueness and superiority of the proposed robust demand-side controls are found as below: a. It is developed based on fundamental studies about uncertainty and a systematic approach to uncertainty analysis. b. It reduces variability of performance under varied conditions, and thus avoids the worst case scenario. c. It is reactive in cases of critical "discrepancies" observed caused by the unpredictable uncertainty that typically scenario uncertainty imposes, and thus it increases control efficiency. This is obtainable by means of i) multi-source composition of weather forecasts including both historical archive and online sources and ii) adaptive Multiple model-based controls (MMC) to mitigate detrimental impacts of varying scenario uncertainties. The proposed robust demand-side control strategy verifies its outstanding demand-side control performance in varied and non-indigenous conditions compared to the existing control strategies including deterministic optimal controls. This result reemphasizes importance of the demand-side control for a building in the global carbon economy. It also demonstrates a capability of risk management of the proposed robust demand-side controls in highly uncertain situations, which eventually attains the maximum benefit in both theoretical and practical perspectives.

The effect of laser focus and process parameters on microstructure and mechanical properties of SLM Inconel 718

NASA Astrophysics Data System (ADS)

Bean, Glenn E.; Witkin, David B.; McLouth, Tait D.; Zaldivar, Rafael J.

2018-02-01

Research on the selective laser melting (SLM) method of laser powder bed fusion additive manufacturing (AM) has shown that surface and internal quality of AM parts is directly related to machine settings such as laser energy density, scanning strategies, and atmosphere. To optimize laser parameters for improved component quality, the energy density is typically controlled via laser power, scanning rate, and scanning strategy, but can also be controlled by changing the spot size via laser focal plane shift. Present work being conducted by The Aerospace Corporation was initiated after observing inconsistent build quality of parts printed using OEM-installed settings. Initial builds of Inconel 718 witness geometries using OEM laser parameters were evaluated for surface roughness, density, and porosity while varying energy density via laser focus shift. Based on these results, hardware and laser parameter adjustments were conducted in order to improve build quality and consistency. Tensile testing was also conducted to investigate the effect of build plate location and laser settings on SLM 718. This work has provided insight into the limitations of OEM parameters compared with optimized parameters towards the goal of manufacturing aerospace-grade parts, and has led to the development of a methodology for laser parameter tuning that can be applied to other alloy systems. Additionally, evidence was found that for 718, which derives its strength from post-manufacturing heat treatment, there is a possibility that tensile testing may not be perceptive to defects which would reduce component performance. Ongoing research is being conducted towards identifying appropriate testing and analysis methods for screening and quality assurance.

Can We Practically Bring Physics-based Modeling Into Operational Analytics Tools?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Granderson, Jessica; Bonvini, Marco; Piette, Mary Ann

We present that analytics software is increasingly used to improve and maintain operational efficiency in commercial buildings. Energy managers, owners, and operators are using a diversity of commercial offerings often referred to as Energy Information Systems, Fault Detection and Diagnostic (FDD) systems, or more broadly Energy Management and Information Systems, to cost-effectively enable savings on the order of ten to twenty percent. Most of these systems use data from meters and sensors, with rule-based and/or data-driven models to characterize system and building behavior. In contrast, physics-based modeling uses first-principles and engineering models (e.g., efficiency curves) to characterize system and buildingmore » behavior. Historically, these physics-based approaches have been used in the design phase of the building life cycle or in retrofit analyses. Researchers have begun exploring the benefits of integrating physics-based models with operational data analytics tools, bridging the gap between design and operations. In this paper, we detail the development and operator use of a software tool that uses hybrid data-driven and physics-based approaches to cooling plant FDD and optimization. Specifically, we describe the system architecture, models, and FDD and optimization algorithms; advantages and disadvantages with respect to purely data-driven approaches; and practical implications for scaling and replicating these techniques. Finally, we conclude with an evaluation of the future potential for such tools and future research opportunities.« less

Vision-based building energy diagnostics and retrofit analysis using 3D thermography and building information modeling

NASA Astrophysics Data System (ADS)

Ham, Youngjib

The emerging energy crisis in the building sector and the legislative measures on improving energy efficiency are steering the construction industry towards adopting new energy efficient design concepts and construction methods that decrease the overall energy loads. However, the problems of energy efficiency are not only limited to the design and construction of new buildings. Today, a significant amount of input energy in existing buildings is still being wasted during the operational phase. One primary source of the energy waste is attributed to unnecessary heat flows through building envelopes during hot and cold seasons. This inefficiency increases the operational frequency of heating and cooling systems to keep the desired thermal comfort of building occupants, and ultimately results in excessive energy use. Improving thermal performance of building envelopes can reduce the energy consumption required for space conditioning and in turn provide building occupants with an optimal thermal comfort at a lower energy cost. In this sense, energy diagnostics and retrofit analysis for existing building envelopes are key enablers for improving energy efficiency. Since proper retrofit decisions of existing buildings directly translate into energy cost saving in the future, building practitioners are increasingly interested in methods for reliable identification of potential performance problems so that they can take timely corrective actions. However, sensing what and where energy problems are emerging or are likely to emerge and then analyzing how the problems influence the energy consumption are not trivial tasks. The overarching goal of this dissertation focuses on understanding the gaps in knowledge in methods for building energy diagnostics and retrofit analysis, and filling these gaps by devising a new method for multi-modal visual sensing and analytics using thermography and Building Information Modeling (BIM). First, to address the challenges in scaling and localization issues of 2D thermal image-based inspection, a new computer vision-based method is presented for automated 3D spatio-thermal modeling of building environments from images and localizing the thermal images into the 3D reconstructed scenes, which helps better characterize the as-is condition of existing buildings in 3D. By using these models, auditors can conduct virtual walk-through in buildings and explore the as-is condition of building geometry and the associated thermal conditions in 3D. Second, to address the challenges in qualitative and subjective interpretation of visual data, a new model-based method is presented to convert the 3D thermal profiles of building environments into their associated energy performance metrics. More specifically, the Energy Performance Augmented Reality (EPAR) models are formed which integrate the actual 3D spatio-thermal models ('as-is') with energy performance benchmarks ('as-designed') in 3D. In the EPAR models, the presence and location of potential energy problems in building environments are inferred based on performance deviations. The as-is thermal resistances of the building assemblies are also calculated at the level of mesh vertex in 3D. Then, based on the historical weather data reflecting energy load for space conditioning, the amount of heat transfer that can be saved by improving the as-is thermal resistances of the defective areas to the recommended level is calculated, and the equivalent energy cost for this saving is estimated. The outcome provides building practitioners with unique information that can facilitate energy efficient retrofit decision-makings. This is a major departure from offhand calculations that are based on historical cost data of industry best practices. Finally, to improve the reliability of BIM-based energy performance modeling and analysis for existing buildings, a new model-based automated method is presented to map actual thermal resistance measurements at the level of 3D vertexes to the associated BIM elements and update their corresponding thermal properties in the gbXML schema. By reflecting the as-is building condition in the BIM-based energy modeling process, this method bridges over the gap between the architectural information in the as-designed BIM and the as-is building condition for accurate energy performance analysis. The performance of each method was validated on ten case studies from interiors and exteriors of existing residential and instructional buildings in IL and VA. The extensive experimental results show the promise of the proposed methods in addressing the fundamental challenges of (1) visual sensing : scaling 2D visual assessments to real-world building environments and localizing energy problems; (2) analytics: subjective and qualitative assessments; and (3) BIM-based building energy analysis : a lack of procedures for reflecting the as-is building condition in the energy modeling process. Beyond the technical contributions, the domain expert surveys conducted in this dissertation show that the proposed methods have potential to improve the quality of thermographic inspection processes and complement the current building energy analysis tools.

Fiscal Year 2013 Net Zero Energy-Water-Waste Portfolio for Fort Leonard Wood

DTIC Science & Technology

2014-12-01

rain sensor /evapotran- spiration central control system. Witnesses said they have seen the system ERDC/CERL SR-14-11 77 in use during rains so it...is possible the system settings and sensors need to be reassessed. Building 6100 The building is an administrative trainee company headquarters...CERL SR-14-11 108 ensure that each watering event is optimally performed during the day. A centrally controlled system with rain sensors should also

On a computational model of building thermal dynamic response

NASA Astrophysics Data System (ADS)

Jarošová, Petra; Vala, Jiří

2016-07-01

Development and exploitation of advanced materials, structures and technologies in civil engineering, both for buildings with carefully controlled interior temperature and for common residential houses, together with new European and national directives and technical standards, stimulate the development of rather complex and robust, but sufficiently simple and inexpensive computational tools, supporting their design and optimization of energy consumption. This paper demonstrates the possibility of consideration of such seemingly contradictory requirements, using the simplified non-stationary thermal model of a building, motivated by the analogy with the analysis of electric circuits; certain semi-analytical forms of solutions come from the method of lines.

Discrete Particle Swarm Optimization Routing Protocol for Wireless Sensor Networks with Multiple Mobile Sinks.

PubMed

Yang, Jin; Liu, Fagui; Cao, Jianneng; Wang, Liangming

2016-07-14

Mobile sinks can achieve load-balancing and energy-consumption balancing across the wireless sensor networks (WSNs). However, the frequent change of the paths between source nodes and the sinks caused by sink mobility introduces significant overhead in terms of energy and packet delays. To enhance network performance of WSNs with mobile sinks (MWSNs), we present an efficient routing strategy, which is formulated as an optimization problem and employs the particle swarm optimization algorithm (PSO) to build the optimal routing paths. However, the conventional PSO is insufficient to solve discrete routing optimization problems. Therefore, a novel greedy discrete particle swarm optimization with memory (GMDPSO) is put forward to address this problem. In the GMDPSO, particle's position and velocity of traditional PSO are redefined under discrete MWSNs scenario. Particle updating rule is also reconsidered based on the subnetwork topology of MWSNs. Besides, by improving the greedy forwarding routing, a greedy search strategy is designed to drive particles to find a better position quickly. Furthermore, searching history is memorized to accelerate convergence. Simulation results demonstrate that our new protocol significantly improves the robustness and adapts to rapid topological changes with multiple mobile sinks, while efficiently reducing the communication overhead and the energy consumption.

Double Wall Framing Technique An Example of High Performance, Sustainable Building Envelope Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kosny, Dr. Jan; Asiz, Andi; Shrestha, Som S

2015-01-01

Double wall technologies utilizing wood framing have been well-known and used in North American buildings for decades. Most of double wall designs use only natural materials such as wood products, gypsum, and cellulose fiber insulation, being one of few building envelope technologies achieving high thermal performance without use of plastic foams or fiberglass. Today, after several material and structural design modifications, these technologies are considered as highly thermally efficient, sustainable option for new constructions and sometimes, for retrofit projects. Following earlier analysis performed for U.S. Department of Energy by Fraunhofer CSE, this paper discusses different ways to build double wallsmore » and to optimize their thermal performance to minimize the space conditioning energy consumption. Description of structural configuration alternatives and thermal performance analysis are presented as well. Laboratory tests to evaluate thermal properties of used insulation and whole wall system thermal performance are also discussed in this paper. Finally, the thermal loads generated in field conditions by double walls are discussed utilizing results from a joined project performed by Zero Energy Building Research Alliance and Oak Ridge National Laboratory (ORNL), which made possible evaluation of the market viability of low-energy homes built in the Tennessee Valley. Experimental data recorded in two of the test houses built during this field study is presented in this work.« less

Comparative analysis of economic models in selected solar energy computer programs

NASA Astrophysics Data System (ADS)

Powell, J. W.; Barnes, K. A.

1982-01-01

The economic evaluation models in five computer programs widely used for analyzing solar energy systems (F-CHART 3.0, F-CHART 4.0, SOLCOST, BLAST, and DOE-2) are compared. Differences in analysis techniques and assumptions among the programs are assessed from the point of view of consistency with the Federal requirements for life cycle costing (10 CFR Part 436), effect on predicted economic performance, and optimal system size, case of use, and general applicability to diverse systems types and building types. The FEDSOL program developed by the National Bureau of Standards specifically to meet the Federal life cycle cost requirements serves as a basis for the comparison. Results of the study are illustrated in test cases of two different types of Federally owned buildings: a single family residence and a low rise office building.

Design of a lens table for a double toroidal electron spectrometer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu Xiaojng; Nicolas, Christophe; Miron, Catalin

2013-03-15

We report here on the method we developed to build a lens table for a four-element electrostatic transfer lens operated together with a double toroidal electron energy analyzer designed by one of us, and whose original design and further improvements are described in detail in Miron et al. [Rev. Sci. Instrum. 68, 3728 (1997)] and Le Guen et al. [Rev. Sci. Instrum. 73, 3885 (2002)]. Both computer simulations and laboratory instrument tuning were performed in order to build this lens table. The obtained result was tested for a broad range of electron kinetic energies and analyzer pass energies. Based onmore » this new lens table, allowing to easily computer control the spectrometer working conditions, we could routinely achieve an electron energy resolution ranging between 0.6% and 0.8% of the analyzer pass energy, while the electron count rate was also significantly improved. The establishment of such a lens table is of high importance to relieve experimentalists from the tedious laboring of the lens optimization, which was previously necessary prior to any measurement. The described method can be adapted to any type of electron/ion energy analyzer, and will thus be interesting for all experimentalists who own, or plan to build or improve their charged particle energy analyzers.« less

The optimal operation of cooling tower systems with variable-frequency control

NASA Astrophysics Data System (ADS)

Cao, Yong; Huang, Liqing; Cui, Zhiguo; Liu, Jing

2018-02-01

This study investigates the energy performance of chiller and cooling tower systems integrated with variable-frequency control for cooling tower fans and condenser water pumps. With regard to an example chiller system serving an office building, Chiller and cooling towers models were developed to assess how different variable-frequency control methods of cooling towers fans and condenser water pumps influence the trade-off between the chiller power, pump power and fan power under various operating conditions. The matching relationship between the cooling tower fans frequency and condenser water pumps frequency at optimal energy consumption of the system is introduced to achieve optimum system performance.

Load management as a smart grid concept for sizing and designing of hybrid renewable energy systems

NASA Astrophysics Data System (ADS)

Eltamaly, Ali M.; Mohamed, Mohamed A.; Al-Saud, M. S.; Alolah, Abdulrahman I.

2017-10-01

Optimal sizing of hybrid renewable energy systems (HRES) to satisfy load requirements with the highest reliability and lowest cost is a crucial step in building HRESs to supply electricity to remote areas. Applying smart grid concepts such as load management can reduce the size of HRES components and reduce the cost of generated energy considerably. In this article, sizing of HRES is carried out by dividing the load into high- and low-priority parts. The proposed system is formed by a photovoltaic array, wind turbines, batteries, fuel cells and a diesel generator as a back-up energy source. A smart particle swarm optimization (PSO) algorithm using MATLAB is introduced to determine the optimal size of the HRES. The simulation was carried out with and without division of the load to compare these concepts. HOMER software was also used to simulate the proposed system without dividing the loads to verify the results obtained from the proposed PSO algorithm. The results show that the percentage of division of the load is inversely proportional to the cost of the generated energy.

Optimization based on benefit of regional energy suppliers of distributed generation in active distribution network

NASA Astrophysics Data System (ADS)

Huo, Xianxu; Li, Guodong; Jiang, Ling; Wang, Xudong

2017-08-01

With the development of electricity market, distributed generation (DG) technology and related policies, regional energy suppliers are encouraged to build DG. Under this background, the concept of active distribution network (ADN) is put forward. In this paper, a bi-level model of intermittent DG considering benefit of regional energy suppliers is proposed. The objective of the upper level is the maximization of benefit of regional energy suppliers. On this basis, the lower level is optimized for each scene. The uncertainties of DG output and load of users, as well as four active management measures, which include demand-side management, curtailing the output power of DG, regulating reactive power compensation capacity and regulating the on-load tap changer, are considered. Harmony search algorithm and particle swarm optimization are combined as a hybrid strategy to solve the model. This model and strategy are tested with IEEE-33 node system, and results of case study indicate that the model and strategy successfully increase the capacity of DG and benefit of regional energy suppliers.

A theoretical investigation on optimal structures of ethane clusters (C2H6)n with n ≤ 25 and their building-up principle.

PubMed

Takeuchi, Hiroshi

2011-05-01

Geometry optimization of ethane clusters (C(2)H(6))(n) in the range of n ≤ 25 is carried out with a Morse potential. A heuristic method based on perturbations of geometries is used to locate global minima of the clusters. The following perturbations are carried out: (1) the molecule or group with the highest energy is moved to the interior of a cluster, (2) it is moved to stable positions on the surface of a cluster, and (3) orientations of one and two molecules are randomly modified. The geometry obtained after each perturbation is optimized by a quasi-Newton method. The global minimum of the dimer is consistent with that previously reported. The putative global minima of the clusters with 3 ≤ n ≤ 25 are first proposed and their building-up principle is discussed. Copyright © 2010 Wiley Periodicals, Inc.

Evaluating economic and environmental aspects of using solar panels on multi-angled facades of office buildings

NASA Astrophysics Data System (ADS)

Hannoudi, Loay Akram; Lauring, Michael; Christensen, Jørgen Erik

2017-09-01

This paper is concerned with using solar panels as high-tech cladding materials on multi-angled facades for office buildings. The energy produced by the solar panels will be consumed inside the office rooms by cooling compressors, ventilation, lighting and office equipment. Each multi-angled facade unit is directed into two different orientations on a vertical axis (right and left), but not tilted up and down. The different facade orientations will optimize the use of solar radiation to produce the needed energy from the solar panels when placing them on the parapets of these facades. In this regard, four scenarios with different facade configurations and orientations are evaluated and discussed. The method for the simulations and calculations depends on two main programs: first, IDA ICE program to calculate the energy consumption and evaluate the indoor climate of the building; and second, PVBAT to calculate the cost of the electricity produced by the solar panels and evaluate the total amount of energy produced from these panels along with the ratio to the energy bought directly from the electricity grid. There is also an environmental evaluation for the system by calculating the CO2 emissions in the different scenarios.

Technology Solutions for New and Existing Homes Case Study: Optimized Slab-on-Grade Foundation Insulation Retrofits

DOE Office of Scientific and Technical Information (OSTI.GOV)

T. Schirber; Goldberg, L.; Mosiman, G.

A more accurate assessment of SOG foundation insulation energy savings than traditionally possible is now feasible. This has been enabled by advances in whole building energy simulation with 3-dimensional foundation modelling integration at each time step together with an experimental measurement of the site energy savings of SOG foundation insulation. Ten SOG insulation strategies were evaluated on a test building to identify an optimum retrofit insulation strategy in a zone 6 climate (Minneapolis, MN). The optimum insulation strategy in terms of energy savings and cost effectiveness consisted of two components: (a) R-20 XPS insulation above grade, and, (b) R-20 insulationmore » at grade (comprising an outer layer of R-10 insulation and an interior layer of R-12 poured polyurethane insulation) tapering to R-10 XPS insulation at half the below-grade wall height (the lower half of the stem wall was uninsulated).« less

Cooperation of Horizontal Ground Heat Exchanger with the Ventilation Unit During Summer - Case Study

NASA Astrophysics Data System (ADS)

Romańska-Zapała, Anna; Furtak, Marcin; Dechnik, Mirosław

2017-10-01

Renewable energy sources are used in the modern energy-efficient buildings to improve their energy balance. One of them is used in the mechanical ventilation system ground air heat exchanger (earth-air heat exchanger - EAHX). This solution, right after heat recovery from exhaust air (recuperation), allows the reduction in the energy needed to obtain the desired temperature of supply air. The article presents the results of "in situ" measurements of pipe ground air heat exchanger cooperating with the air handling unit, supporting cooling the building in the summer season, in Polish climatic conditions. The laboratory consists of a ventilation unit intake - exhaust with rotor for which the source of fresh air is the air intake wall and two air intakes field cooperating with the tube with ground air heat exchangers. Selection of the source of fresh air is performed using sprocket with actuators. This system is part of the ventilation system of the Malopolska Laboratory of Energy-Efficient Building (MLBE) building of Cracow University of Technology. The measuring system are, among others, the sensors of parameters of air inlets and outlets of the heat exchanger channels EAHX and weather station that senses the local weather conditions. The measurement data are recorded and archived by the integrated process control system in the building of MLBE. During the study measurements of operating parameters of the ventilation unit cooperating with the selected source of fresh air were performed. Two cases of operation of the system: using EAHX heat exchanger and without it, were analyzed. Potentially the use of ground air heat exchanger in the mechanical ventilation system can reduce the energy demand for heating or cooling rooms by the pre-adjustment of the supply air temperature. Considering the results can be concluded that the continuous use of these exchangers is not optimal. This relationship is appropriate not only on an annual basis for the transitional periods (spring and autumn), but also in individual days in the potentially most favorable periods of work exchanger (summer and winter). Inappropriate operation of the heat exchanger, will lead to a temporary increase in energy consumption for the preparation of the desired air temperature, relative to the fresh air unit which is non-pretreated. For optimal energy system operation: exchanger EAHX - air handling unit, to preserve the most favourable parameters of inlet air to handling unit, there is a need to dynamically adjust the source of fresh air, depending on changing external conditions and the required outlet temperature of central unit (temperature of air forced to the rooms).

Optimal Rate Schedules with Data Sharing in Energy Harvesting Communication Systems.

PubMed

Wu, Weiwei; Li, Huafan; Shan, Feng; Zhao, Yingchao

2017-12-20

Despite the abundant research on energy-efficient rate scheduling polices in energy harvesting communication systems, few works have exploited data sharing among multiple applications to further enhance the energy utilization efficiency, considering that the harvested energy from environments is limited and unstable. In this paper, to overcome the energy shortage of wireless devices at transmitting data to a platform running multiple applications/requesters, we design rate scheduling policies to respond to data requests as soon as possible by encouraging data sharing among data requests and reducing the redundancy. We formulate the problem as a transmission completion time minimization problem under constraints of dynamical data requests and energy arrivals. We develop offline and online algorithms to solve this problem. For the offline setting, we discover the relationship between two problems: the completion time minimization problem and the energy consumption minimization problem with a given completion time. We first derive the optimal algorithm for the min-energy problem and then adopt it as a building block to compute the optimal solution for the min-completion-time problem. For the online setting without future information, we develop an event-driven online algorithm to complete the transmission as soon as possible. Simulation results validate the efficiency of the proposed algorithm.

Optimal Rate Schedules with Data Sharing in Energy Harvesting Communication Systems

PubMed Central

Wu, Weiwei; Li, Huafan; Shan, Feng; Zhao, Yingchao

2017-01-01

Despite the abundant research on energy-efficient rate scheduling polices in energy harvesting communication systems, few works have exploited data sharing among multiple applications to further enhance the energy utilization efficiency, considering that the harvested energy from environments is limited and unstable. In this paper, to overcome the energy shortage of wireless devices at transmitting data to a platform running multiple applications/requesters, we design rate scheduling policies to respond to data requests as soon as possible by encouraging data sharing among data requests and reducing the redundancy. We formulate the problem as a transmission completion time minimization problem under constraints of dynamical data requests and energy arrivals. We develop offline and online algorithms to solve this problem. For the offline setting, we discover the relationship between two problems: the completion time minimization problem and the energy consumption minimization problem with a given completion time. We first derive the optimal algorithm for the min-energy problem and then adopt it as a building block to compute the optimal solution for the min-completion-time problem. For the online setting without future information, we develop an event-driven online algorithm to complete the transmission as soon as possible. Simulation results validate the efficiency of the proposed algorithm. PMID:29261135

Metrics for building performance assurance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koles, G.; Hitchcock, R.; Sherman, M.

This report documents part of the work performed in phase I of a Laboratory Directors Research and Development (LDRD) funded project entitled Building Performance Assurances (BPA). The focus of the BPA effort is to transform the way buildings are built and operated in order to improve building performance by facilitating or providing tools, infrastructure, and information. The efforts described herein focus on the development of metrics with which to evaluate building performance and for which information and optimization tools need to be developed. The classes of building performance metrics reviewed are (1) Building Services (2) First Costs, (3) Operating Costs,more » (4) Maintenance Costs, and (5) Energy and Environmental Factors. The first category defines the direct benefits associated with buildings; the next three are different kinds of costs associated with providing those benefits; the last category includes concerns that are broader than direct costs and benefits to the building owner and building occupants. The level of detail of the various issues reflect the current state of knowledge in those scientific areas and the ability of the to determine that state of knowledge, rather than directly reflecting the importance of these issues; it intentionally does not specifically focus on energy issues. The report describes work in progress and is intended as a resource and can be used to indicate the areas needing more investigation. Other reports on BPA activities are also available.« less

Integrated Building Management System (IBMS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anita Lewis

This project provides a combination of software and services that more easily and cost-effectively help to achieve optimized building performance and energy efficiency. Featuring an open-platform, cloud- hosted application suite and an intuitive user experience, this solution simplifies a traditionally very complex process by collecting data from disparate building systems and creating a single, integrated view of building and system performance. The Fault Detection and Diagnostics algorithms developed within the IBMS have been designed and tested as an integrated component of the control algorithms running the equipment being monitored. The algorithms identify the normal control behaviors of the equipment withoutmore » interfering with the equipment control sequences. The algorithms also work without interfering with any cooperative control sequences operating between different pieces of equipment or building systems. In this manner the FDD algorithms create an integrated building management system.« less

Potential impacts of climate change on the built environment: ASHRAE climate zones, building codes and national energy efficiency

DOE Office of Scientific and Technical Information (OSTI.GOV)

New, Joshua Ryan; Kumar, Jitendra; Hoffman, Forrest M.

Statement of the Problem: ASHRAE releases updates to 90.1 “Energy Standard for Buildings except Low-Rise Residential Buildings” every three years resulting in a 3.7%-17.3% increase in energy efficiency for buildings with each release. This is adopted by or informs building codes in nations across the globe, is the National Standard for the US, and individual states elect which release year of the standard they will enforce. These codes are built upon Standard 169 “Climatic Data for Building Design Standards,” the latest 2017 release of which defines climate zones based on 8, 118 weather stations throughout the world and data frommore » the past 8-25 years. This data may not be indicative of the weather that new buildings built today, will see during their upcoming 30-120 year lifespan. Methodology & Theoretical Orientation: Using more modern, high-resolution datasets from climate satellites, IPCC climate models (PCM and HadGCM), high performance computing resources (Titan) and new capabilities for clustering and optimization the authors briefly analyzed different methods for redefining climate zones. Using bottom-up analysis of multiple meteorological variables which were the subject matter, experts selected as being important to energy consumption, rather than the heating/cooling degree days currently used. Findings: We analyzed the accuracy of redefined climate zones, compared to current climate zones and how the climate zones moved under different climate change scenarios, and quantified the accuracy of these methods on a local level, at a national scale for the US. Conclusion & Significance: There is likely to be a significant annual, national energy and cost (billions USD) savings that could be realized by adjusting climate zones to take into account anticipated trends or scenarios in regional weather patterns.« less

Interdisciplinary design study of a high-rise integrated roof wind energy system

NASA Astrophysics Data System (ADS)

Dekker, R. W. A.; Ferraro, R. M.; Suma, A. B.; Moonen, S. P. G.

2012-10-01

Today's market in micro-wind turbines is in constant development introducing more efficient solutions for the future. Besides the private use of tower supported turbines, opportunities to integrate wind turbines in the built environment arise. The Integrated Roof Wind Energy System (IRWES) presented in this work is a modular roof structure integrated on top of existing or new buildings. IRWES is build up by an axial array of skewed shaped funnels used for both wind inlet and outlet. This inventive use of shape and geometry leads to a converging air capturing inlet to create high wind mass flow and velocity toward a Vertical Axis Wind Turbine (VAWT) in the center-top of the roof unit for the generation of a relatively high amount of energy. The scope of this research aims to make an optimized structural design of IRWES to be placed on top of the Vertigo building in Eindhoven; analysis of the structural performance; and impact to the existing structure by means of Finite Element Modeling (FEM). Results show that the obvious impact of wind pressure to the structural design is easily supported in different configurations of fairly simple lightweight structures. In particular, the weight addition to existing buildings remains minimal.

High-resolution comparative modeling with RosettaCM.

PubMed

Song, Yifan; DiMaio, Frank; Wang, Ray Yu-Ruei; Kim, David; Miles, Chris; Brunette, Tj; Thompson, James; Baker, David

2013-10-08

We describe an improved method for comparative modeling, RosettaCM, which optimizes a physically realistic all-atom energy function over the conformational space defined by homologous structures. Given a set of sequence alignments, RosettaCM assembles topologies by recombining aligned segments in Cartesian space and building unaligned regions de novo in torsion space. The junctions between segments are regularized using a loop closure method combining fragment superposition with gradient-based minimization. The energies of the resulting models are optimized by all-atom refinement, and the most representative low-energy model is selected. The CASP10 experiment suggests that RosettaCM yields models with more accurate side-chain and backbone conformations than other methods when the sequence identity to the templates is greater than ∼15%. Copyright © 2013 Elsevier Ltd. All rights reserved.

Optimal integration of a hybrid solar-battery power source into smart home nanogrid with plug-in electric vehicle

NASA Astrophysics Data System (ADS)

Wu, Xiaohua; Hu, Xiaosong; Teng, Yanqiong; Qian, Shide; Cheng, Rui

2017-09-01

Hybrid solar-battery power source is essential in the nexus of plug-in electric vehicle (PEV), renewables, and smart building. This paper devises an optimization framework for efficient energy management and components sizing of a single smart home with home battery, PEV, and potovoltatic (PV) arrays. We seek to maximize the home economy, while satisfying home power demand and PEV driving. Based on the structure and system models of the smart home nanogrid, a convex programming (CP) problem is formulated to rapidly and efficiently optimize both the control decision and parameters of the home battery energy storage system (BESS). Considering different time horizons of optimization, home BESS prices, types and control modes of PEVs, the parameters of home BESS and electric cost are systematically investigated. Based on the developed CP control law in home to vehicle (H2V) mode and vehicle to home (V2H) mode, the home with BESS does not buy electric energy from the grid during the electric price's peak periods.

Peculiarities of non-autoclaved lime wall materials production using clays

NASA Astrophysics Data System (ADS)

Volodchenko, A. A.; Lesovik, V. S.; Cherepanova, I. A.; Volodchenko, A. N.; Zagorodnjuk, L. H.; Elistratkin, M. Y.

2018-03-01

At present, the development and implementation of energy saving technologies for building materials production, which correspond to modern trends of «green» technologies, become ever more popular. One of the most widely spread wall materials today is a lime brick and stones. The primary raw goods used in production of such materials are quarziferous rocks. However, they have some disadvantages, including low strength index at the intermediate phase of their production, especially in case with a raw brick, which is an issue in the production of high-hollow goods due to low strength index of raw materials and the nonoptimal matrix structure. The conducted experiments confirmed the possibility to control structurization of building composites due to application of nonconventional argillous raw materials. Besides, the material and mineral composition of nonconventional clay rocks ensures the optimal microstructure thus providing for the production of efficient wall building materials via energy saving technology.

An Adaptive Intelligent Integrated Lighting Control Approach for High-Performance Office Buildings

NASA Astrophysics Data System (ADS)

Karizi, Nasim

An acute and crucial societal problem is the energy consumed in existing commercial buildings. There are 1.5 million commercial buildings in the U.S. with only about 3% being built each year. Hence, existing buildings need to be properly operated and maintained for several decades. Application of integrated centralized control systems in buildings could lead to more than 50% energy savings. This research work demonstrates an innovative adaptive integrated lighting control approach which could achieve significant energy savings and increase indoor comfort in high performance office buildings. In the first phase of the study, a predictive algorithm was developed and validated through experiments in an actual test room. The objective was to regulate daylight on a specified work plane by controlling the blind slat angles. Furthermore, a sensor-based integrated adaptive lighting controller was designed in Simulink which included an innovative sensor optimization approach based on genetic algorithm to minimize the number of sensors and efficiently place them in the office. The controller was designed based on simple integral controllers. The objective of developed control algorithm was to improve the illuminance situation in the office through controlling the daylight and electrical lighting. To evaluate the performance of the system, the controller was applied on experimental office model in Lee et al.'s research study in 1998. The result of the developed control approach indicate a significantly improvement in lighting situation and 1-23% and 50-78% monthly electrical energy savings in the office model, compared to two static strategies when the blinds were left open and closed during the whole year respectively.

Applied Distributed Model Predictive Control for Energy Efficient Buildings and Ramp Metering

NASA Astrophysics Data System (ADS)

Koehler, Sarah Muraoka

Industrial large-scale control problems present an interesting algorithmic design challenge. A number of controllers must cooperate in real-time on a network of embedded hardware with limited computing power in order to maximize system efficiency while respecting constraints and despite communication delays. Model predictive control (MPC) can automatically synthesize a centralized controller which optimizes an objective function subject to a system model, constraints, and predictions of disturbance. Unfortunately, the computations required by model predictive controllers for large-scale systems often limit its industrial implementation only to medium-scale slow processes. Distributed model predictive control (DMPC) enters the picture as a way to decentralize a large-scale model predictive control problem. The main idea of DMPC is to split the computations required by the MPC problem amongst distributed processors that can compute in parallel and communicate iteratively to find a solution. Some popularly proposed solutions are distributed optimization algorithms such as dual decomposition and the alternating direction method of multipliers (ADMM). However, these algorithms ignore two practical challenges: substantial communication delays present in control systems and also problem non-convexity. This thesis presents two novel and practically effective DMPC algorithms. The first DMPC algorithm is based on a primal-dual active-set method which achieves fast convergence, making it suitable for large-scale control applications which have a large communication delay across its communication network. In particular, this algorithm is suited for MPC problems with a quadratic cost, linear dynamics, forecasted demand, and box constraints. We measure the performance of this algorithm and show that it significantly outperforms both dual decomposition and ADMM in the presence of communication delay. The second DMPC algorithm is based on an inexact interior point method which is suited for nonlinear optimization problems. The parallel computation of the algorithm exploits iterative linear algebra methods for the main linear algebra computations in the algorithm. We show that the splitting of the algorithm is flexible and can thus be applied to various distributed platform configurations. The two proposed algorithms are applied to two main energy and transportation control problems. The first application is energy efficient building control. Buildings represent 40% of energy consumption in the United States. Thus, it is significant to improve the energy efficiency of buildings. The goal is to minimize energy consumption subject to the physics of the building (e.g. heat transfer laws), the constraints of the actuators as well as the desired operating constraints (thermal comfort of the occupants), and heat load on the system. In this thesis, we describe the control systems of forced air building systems in practice. We discuss the "Trim and Respond" algorithm which is a distributed control algorithm that is used in practice, and show that it performs similarly to a one-step explicit DMPC algorithm. Then, we apply the novel distributed primal-dual active-set method and provide extensive numerical results for the building MPC problem. The second main application is the control of ramp metering signals to optimize traffic flow through a freeway system. This application is particularly important since urban congestion has more than doubled in the past few decades. The ramp metering problem is to maximize freeway throughput subject to freeway dynamics (derived from mass conservation), actuation constraints, freeway capacity constraints, and predicted traffic demand. In this thesis, we develop a hybrid model predictive controller for ramp metering that is guaranteed to be persistently feasible and stable. This contrasts to previous work on MPC for ramp metering where such guarantees are absent. We apply a smoothing method to the hybrid model predictive controller and apply the inexact interior point method to this nonlinear non-convex ramp metering problem.

Modeling and Analysis of Commercial Building Electrical Loads for Demand Side Management

NASA Astrophysics Data System (ADS)

Berardino, Jonathan

In recent years there has been a push in the electric power industry for more customer involvement in the electricity markets. Traditionally the end user has played a passive role in the planning and operation of the power grid. However, many energy markets have begun opening up opportunities to consumers who wish to commit a certain amount of their electrical load under various demand side management programs. The potential benefits of more demand participation include reduced operating costs and new revenue opportunities for the consumer, as well as more reliable and secure operations for the utilities. The management of these load resources creates challenges and opportunities to the end user that were not present in previous market structures. This work examines the behavior of commercial-type building electrical loads and their capacity for supporting demand side management actions. This work is motivated by the need for accurate and dynamic tools to aid in the advancement of demand side operations. A dynamic load model is proposed for capturing the response of controllable building loads. Building-specific load forecasting techniques are developed, with particular focus paid to the integration of building management system (BMS) information. These approaches are tested using Drexel University building data. The application of building-specific load forecasts and dynamic load modeling to the optimal scheduling of multi-building systems in the energy market is proposed. Sources of potential load uncertainty are introduced in the proposed energy management problem formulation in order to investigate the impact on the resulting load schedule.

Building America Case Study: Balancing Hydronic Systems in Multifamily Buildings, Chicago, Illinois (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

2014-09-01

In multifamily hydronic systems, temperature imbalance may be caused by undersized piping, improperly adjusted balancing valves, inefficient water temperature and flow levels, and owner/occupant interaction with the boilers, distribution and controls. The effects of imbalance include tenant discomfort, higher energy use intensity and inefficient building operation. This paper explores cost-effective distribution upgrades and balancing measures in multifamily hydronic systems, providing a resource to contractors, auditors, and building owners on best practices to improve tenant comfort and lower operating costs. The research was conducted by The Partnership for Advanced Residential Retrofit (PARR) in conjunction with Elevate Energy. The team surveyed existingmore » knowledge on cost-effective retrofits for optimizing distribution in typical multifamily hydronic systems, with the aim of identifying common situations and solutions, and then conducted case studies on two Chicago area buildings with known balancing issues in order to quantify the extent of temperature imbalance. At one of these buildings a booster pump was installed on a loop to an underheated wing of the building. This study found that unit temperature in a multifamily hydronic building can vary as much as 61 degrees F, particularly if windows are opened or tenants use intermittent supplemental heating sources like oven ranges. Average temperature spread at the building as a result of this retrofit decreased from 22.1 degrees F to 15.5 degrees F.« less

Intelligent demand side management of residential building energy systems

NASA Astrophysics Data System (ADS)

Sinha, Maruti N.

Advent of modern sensing technologies, data processing capabilities and rising cost of energy are driving the implementation of intelligent systems in buildings and houses which constitute 41% of total energy consumption. The primary motivation has been to provide a framework for demand-side management and to improve overall reliability. The entire formulation is to be implemented on NILM (Non-Intrusive Load Monitoring System), a smart meter. This is going to play a vital role in the future of demand side management. Utilities have started deploying smart meters throughout the world which will essentially help to establish communication between utility and consumers. This research is focused on investigation of a suitable thermal model of residential house, building up control system and developing diagnostic and energy usage forecast tool. The present work has considered measurement based approach to pursue. Identification of building thermal parameters is the very first step towards developing performance measurement and controls. The proposed identification technique is PEM (Prediction Error Method) based, discrete state-space model. The two different models have been devised. First model is focused toward energy usage forecast and diagnostics. Here one of the novel idea has been investigated which takes integral of thermal capacity to identify thermal model of house. The purpose of second identification is to build up a model for control strategy. The controller should be able to take into account the weather forecast information, deal with the operating point constraints and at the same time minimize the energy consumption. To design an optimal controller, MPC (Model Predictive Control) scheme has been implemented instead of present thermostatic/hysteretic control. This is a receding horizon approach. Capability of the proposed schemes has also been investigated.

Discrete Particle Swarm Optimization Routing Protocol for Wireless Sensor Networks with Multiple Mobile Sinks

PubMed Central

Yang, Jin; Liu, Fagui; Cao, Jianneng; Wang, Liangming

2016-01-01

Mobile sinks can achieve load-balancing and energy-consumption balancing across the wireless sensor networks (WSNs). However, the frequent change of the paths between source nodes and the sinks caused by sink mobility introduces significant overhead in terms of energy and packet delays. To enhance network performance of WSNs with mobile sinks (MWSNs), we present an efficient routing strategy, which is formulated as an optimization problem and employs the particle swarm optimization algorithm (PSO) to build the optimal routing paths. However, the conventional PSO is insufficient to solve discrete routing optimization problems. Therefore, a novel greedy discrete particle swarm optimization with memory (GMDPSO) is put forward to address this problem. In the GMDPSO, particle’s position and velocity of traditional PSO are redefined under discrete MWSNs scenario. Particle updating rule is also reconsidered based on the subnetwork topology of MWSNs. Besides, by improving the greedy forwarding routing, a greedy search strategy is designed to drive particles to find a better position quickly. Furthermore, searching history is memorized to accelerate convergence. Simulation results demonstrate that our new protocol significantly improves the robustness and adapts to rapid topological changes with multiple mobile sinks, while efficiently reducing the communication overhead and the energy consumption. PMID:27428971

Scaling and Optimization of Magnetic Refrigeration for Commercial Building HVAC Systems Greater than 175 kW in Capacity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abdelaziz, Omar; West, David L; Mallow, Anne M

Heating, ventilation, air-conditioning and refrigeration (HVACR) account for approximately one- third of building energy consumption. Magnetic refrigeration presents an opportunity for significant energy savings and emissions reduction for serving the building heating, cooling, and refrigeration loads. In this paper, we have examined the magnet and MCE material requirements for scaling magnetic refrigeration systems for commercial building cooling applications. Scaling relationships governing the resources required for magnetic refrigeration systems have been developed. As system refrigeration capacity increases, the use of superconducting magnet systems becomes more applicable, and a comparison is presented of system requirements for permanent and superconducting (SC) magnetization systems.more » Included in this analysis is an investigation of the ability of superconducting magnet based systems to overcome the parasitic power penalty of the cryocooler used to keep SC windings at cryogenic temperatures. Scaling relationships were used to develop the initial specification for a SC magnet-based active magnetic regeneration (AMR) system. An optimized superconducting magnet was designed to support this system. In this analysis, we show that the SC magnet system consisting of two 0.38 m3 regenerators is capable of producing 285 kW of cooling power with a T of 28 K. A system COP of 4.02 including cryocooler and fan losses which illustrates that an SC magnet-based system can operate with efficiency comparable to traditional systems and deliver large cooling powers of 285.4 kW (81.2 Tons).« less

Optimal dynamic voltage scaling for wireless sensor nodes with real-time constraints

NASA Astrophysics Data System (ADS)

Cassandras, Christos G.; Zhuang, Shixin

2005-11-01

Sensors are increasingly embedded in manufacturing systems and wirelessly networked to monitor and manage operations ranging from process and inventory control to tracking equipment and even post-manufacturing product monitoring. In building such sensor networks, a critical issue is the limited and hard to replenish energy in the devices involved. Dynamic voltage scaling is a technique that controls the operating voltage of a processor to provide desired performance while conserving energy and prolonging the overall network's lifetime. We consider such power-limited devices processing time-critical tasks which are non-preemptive, aperiodic and have uncertain arrival times. We treat voltage scaling as a dynamic optimization problem whose objective is to minimize energy consumption subject to hard or soft real-time execution constraints. In the case of hard constraints, we build on prior work (which engages a voltage scaling controller at task completion times) by developing an intra-task controller that acts at all arrival times of incoming tasks. We show that this optimization problem can be decomposed into two simpler ones whose solution leads to an algorithm that does not actually require solving any nonlinear programming problems. In the case of soft constraints, this decomposition must be partly relaxed, but it still leads to a scalable (linear in the number of tasks) algorithm. Simulation results are provided to illustrate performance improvements in systems with intra-task controllers compared to uncontrolled systems or those using inter-task control.

NASA advanced design program: Analysis, design, and construction of a solar powered aircraft. B.S. Thesis

NASA Technical Reports Server (NTRS)

Chan, Agnes; Conley, Kristin; Javorski, Christian T.; Cheung, Kwok-Hung; Crivelli, Paul M.; Torrey, Nancy P.; Traver, Michael L.

1992-01-01

Increase in energy demands coupled with rapid depletion of natural energy resources have deemed solar energy as the most logical alternative source of power. The major objective of this project was to build a solar powered remotely controlled aircraft to demonstrate the feasibility of solar energy as an effective, alternate source of power. The final design was optimized for minimum weight and maximum strength of the structure. These design constraints necessitated a carbon fiber composite structure. Surya is a lightweight, durable aircraft capable of achieving level flight powered entirely by solar cells.

Distributed dynamic simulations of networked control and building performance applications.

PubMed

Yahiaoui, Azzedine

2018-02-01

The use of computer-based automation and control systems for smart sustainable buildings, often so-called Automated Buildings (ABs), has become an effective way to automatically control, optimize, and supervise a wide range of building performance applications over a network while achieving the minimum energy consumption possible, and in doing so generally refers to Building Automation and Control Systems (BACS) architecture. Instead of costly and time-consuming experiments, this paper focuses on using distributed dynamic simulations to analyze the real-time performance of network-based building control systems in ABs and improve the functions of the BACS technology. The paper also presents the development and design of a distributed dynamic simulation environment with the capability of representing the BACS architecture in simulation by run-time coupling two or more different software tools over a network. The application and capability of this new dynamic simulation environment are demonstrated by an experimental design in this paper.

Distributed dynamic simulations of networked control and building performance applications

PubMed Central

Yahiaoui, Azzedine

2017-01-01

The use of computer-based automation and control systems for smart sustainable buildings, often so-called Automated Buildings (ABs), has become an effective way to automatically control, optimize, and supervise a wide range of building performance applications over a network while achieving the minimum energy consumption possible, and in doing so generally refers to Building Automation and Control Systems (BACS) architecture. Instead of costly and time-consuming experiments, this paper focuses on using distributed dynamic simulations to analyze the real-time performance of network-based building control systems in ABs and improve the functions of the BACS technology. The paper also presents the development and design of a distributed dynamic simulation environment with the capability of representing the BACS architecture in simulation by run-time coupling two or more different software tools over a network. The application and capability of this new dynamic simulation environment are demonstrated by an experimental design in this paper. PMID:29568135

From Smart-Eco Building to High-Performance Architecture: Optimization of Energy Consumption in Architecture of Developing Countries

NASA Astrophysics Data System (ADS)

Mahdavinejad, M.; Bitaab, N.

2017-08-01

Search for high-performance architecture and dreams of future architecture resulted in attempts towards meeting energy efficient architecture and planning in different aspects. Recent trends as a mean to meet future legacy in architecture are based on the idea of innovative technologies for resource efficient buildings, performative design, bio-inspired technologies etc. while there are meaningful differences between architecture of developed and developing countries. Significance of issue might be understood when the emerging cities are found interested in Dubaization and other related booming development doctrines. This paper is to analyze the level of developing countries’ success to achieve smart-eco buildings’ goals and objectives. Emerging cities of West of Asia are selected as case studies of the paper. The results of the paper show that the concept of high-performance architecture and smart-eco buildings are different in developing countries in comparison with developed countries. The paper is to mention five essential issues in order to improve future architecture of developing countries: 1- Integrated Strategies for Energy Efficiency, 2- Contextual Solutions, 3- Embedded and Initial Energy Assessment, 4- Staff and Occupancy Wellbeing, 5- Life-Cycle Monitoring.

Optimizing read-out of the NECTAr front-end electronics

NASA Astrophysics Data System (ADS)

Vorobiov, S.; Feinstein, F.; Bolmont, J.; Corona, P.; Delagnes, E.; Falvard, A.; Gascón, D.; Glicenstein, J.-F.; Naumann, C. L.; Nayman, P.; Ribo, M.; Sanuy, A.; Tavernet, J.-P.; Toussenel, F.; Vincent, P.

2012-12-01

We describe the optimization of the read-out specifications of the NECTAr front-end electronics for the Cherenkov Telescope Array (CTA). The NECTAr project aims at building and testing a demonstrator module of a new front-end electronics design, which takes an advantage of the know-how acquired while building the cameras of the CAT, H.E.S.S.-I and H.E.S.S.-II experiments. The goal of the optimization work is to define the specifications of the digitizing electronics of a CTA camera, in particular integration time window, sampling rate, analog bandwidth using physics simulations. We employed for this work real photomultiplier pulses, sampled at 100 ps with a 600 MHz bandwidth oscilloscope. The individual pulses are drawn randomly at the times at which the photo-electrons, originating from atmospheric showers, arrive at the focal planes of imaging atmospheric Cherenkov telescopes. The timing information is extracted from the existing CTA simulations on the GRID and organized in a local database, together with all the relevant physical parameters (energy, primary particle type, zenith angle, distance from the shower axis, pixel offset from the optical axis, night-sky background level, etc.), and detector configurations (telescope types, camera/mirror configurations, etc.). While investigating the parameter space, an optimal pixel charge integration time window, which minimizes relative error in the measured charge, has been determined. This will allow to gain in sensitivity and to lower the energy threshold of CTA telescopes. We present results of our optimizations and first measurements obtained using the NECTAr demonstrator module.

Solar energy potential of the largest buildings in the United States

NASA Astrophysics Data System (ADS)

Wence, E. R.; Grodsky, S.; Hernandez, R. R.

2017-12-01

Sustainable pathways of land use for energy are necessary to mitigate climate change and limit conversion of finite land resources needed for conservation and food production. Large, commercial buildings (LCBs) are increasing in size and number throughout the United States (US) and may serve as suitable recipient environments for photovoltaic (PV) solar energy infrastructure that may support a low carbon, low land footprint energy transition. In this study, we identified, characterized, and evaluated the technical potential of the largest, commercial building rooftops (i.e., exceeding 110,000 m2) and their associated parking lots in the US for PV solar energy systems using Aurora, a cloud-based solar optimization platform. We also performed a case study of building-specific electricity generation: electricity consumption balance. Further, we quantified the environmental co-benefit of land sparing and associated avoided emissions (t-CO2-eq) conferred under the counterfactual scenario that solar development would otherwise proceed as a ground-mounted, utility-scale PV installation of equal nominal capacity. We identified and mapped 37 LCBs (by rooftop area) across 18 states in the US, spanning from as far north as the state of Minnesota to as far south as Florida. Rooftop footprints range from 427,297 to 113,689 m2 and have a cumulative surface area of 99.8 million ft2. We characterize the LCBs as either: distribution/warehouse, factory, shopping center, or administrative office/facility. Three of the 37 LCBs currently support rooftop PV and the numbers of associated, detached buildings number up to 38. This study elucidates the extent to which LCBs and their respective parking lots can serve as suitable sites for PV solar energy generation. Lastly, this study demonstrates research-based applications of the Aurora energy modeling platform and informs decision-making focused on redirecting energy development towards human-modified landscapes to prioritize land use for biodiversity and agriculture.

Effect of energy-efficient measures in building construction on indoor radon in Russia.

PubMed

Vasilyev, A; Yarmoshenko, I

2017-04-28

The effect of implementation of energy-efficient measures in building construction was studied. Analysis includes study of indoor radon in energy-efficient buildings in Ekaterinburg, Russia, and results of radiation measurements in 83 regions of Russia conducted within the regional programmes. The forecast distribution of radon concentration in Ekaterinburg was built with regard to the city development programme. With Ekaterinburg taken as representative case, forecast distribution of radon concentration in Russia in 2030 was built. In comparison with 2000, average radon concentration increases by a factor of 1.42 in 2030 year; percentage above the reference level 300 Bq/m3 increases by a factor of 4 in 2030 year. It is necessary to perceive such an increase with all seriousness and to prepare appropriate measures for optimization of protection against indoor radon. Despite the high uncertainty, reconstructed distribution of radon concentration can be applied for justification of measures to be incorporated in the radon mitigation strategy. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Building America Case Study: Optimized Slab-on-Grade Foundation Insulation Retrofits, Madison, Wisconsin

DOE Office of Scientific and Technical Information (OSTI.GOV)

A more accurate assessment of SOG foundation insulation energy savings than traditionally possible is now feasible. This has been enabled by advances in whole building energy simulation with 3-dimensional foundation modelling integration at each time step together with an experimental measurement of the site energy savings of SOG foundation insulation. Ten SOG insulation strategies were evaluated on a test building to identify an optimum retrofit insulation strategy in a zone 6 climate (Minneapolis, MN). The optimum insulation strategy in terms of energy savings and cost effectiveness consisted of two components: (a) R-20 XPS insulation above grade, and, (b) R-20 insulationmore » at grade (comprising an outer layer of R-10 insulation and an interior layer of R-12 poured polyurethane insulation) tapering to R-10 XPS insulation at half the below-grade wall height (the lower half of the stem wall was uninsulated). The optimum insulation strategy was applied to single and multi-family residential buildings in climate zone 4 - 7. The highest site energy savings of 5% was realized for a single family home in Duluth, MN, and the lowest savings of 1.4 percent for a 4-unit townhouse in Richmond, VA. SOG foundation insulation retrofit simple paybacks ranged from 18 to 47 years. There are other benefits of SOG foundation insulation resulting from the increase in the slab surface temperatures. These include increased occupant thermal comfort, and a decrease in slab surface condensation particularly around the slab perimeter.« less

Gradient boosting machine for modeling the energy consumption of commercial buildings

DOE PAGES

Touzani, Samir; Granderson, Jessica; Fernandes, Samuel

2017-11-26

Accurate savings estimations are important to promote energy efficiency projects and demonstrate their cost-effectiveness. The increasing presence of advanced metering infrastructure (AMI) in commercial buildings has resulted in a rising availability of high frequency interval data. These data can be used for a variety of energy efficiency applications such as demand response, fault detection and diagnosis, and heating, ventilation, and air conditioning (HVAC) optimization. This large amount of data has also opened the door to the use of advanced statistical learning models, which hold promise for providing accurate building baseline energy consumption predictions, and thus accurate saving estimations. The gradientmore » boosting machine is a powerful machine learning algorithm that is gaining considerable traction in a wide range of data driven applications, such as ecology, computer vision, and biology. In the present work an energy consumption baseline modeling method based on a gradient boosting machine was proposed. To assess the performance of this method, a recently published testing procedure was used on a large dataset of 410 commercial buildings. The model training periods were varied and several prediction accuracy metrics were used to evaluate the model's performance. The results show that using the gradient boosting machine model improved the R-squared prediction accuracy and the CV(RMSE) in more than 80 percent of the cases, when compared to an industry best practice model that is based on piecewise linear regression, and to a random forest algorithm.« less

Gradient boosting machine for modeling the energy consumption of commercial buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Touzani, Samir; Granderson, Jessica; Fernandes, Samuel

Accurate savings estimations are important to promote energy efficiency projects and demonstrate their cost-effectiveness. The increasing presence of advanced metering infrastructure (AMI) in commercial buildings has resulted in a rising availability of high frequency interval data. These data can be used for a variety of energy efficiency applications such as demand response, fault detection and diagnosis, and heating, ventilation, and air conditioning (HVAC) optimization. This large amount of data has also opened the door to the use of advanced statistical learning models, which hold promise for providing accurate building baseline energy consumption predictions, and thus accurate saving estimations. The gradientmore » boosting machine is a powerful machine learning algorithm that is gaining considerable traction in a wide range of data driven applications, such as ecology, computer vision, and biology. In the present work an energy consumption baseline modeling method based on a gradient boosting machine was proposed. To assess the performance of this method, a recently published testing procedure was used on a large dataset of 410 commercial buildings. The model training periods were varied and several prediction accuracy metrics were used to evaluate the model's performance. The results show that using the gradient boosting machine model improved the R-squared prediction accuracy and the CV(RMSE) in more than 80 percent of the cases, when compared to an industry best practice model that is based on piecewise linear regression, and to a random forest algorithm.« less

Balancing Hydronic Systems in Multifamily Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruch, R.; Ludwig, P.; Maurer, T.

2014-07-01

In multifamily hydronic systems, temperature imbalance may be caused by undersized piping, improperly adjusted balancing valves, inefficient water temperature and flow levels, and owner/occupant interaction with the boilers, distribution and controls. The effects of imbalance include tenant discomfort, higher energy use intensity and inefficient building operation. This paper explores cost-effective distribution upgrades and balancing measures in multifamily hydronic systems, providing a resource to contractors, auditors, and building owners on best practices to improve tenant comfort and lower operating costs. The research was conducted by The Partnership for Advanced Residential Retrofit (PARR) in conjunction with Elevate Energy. The team surveyed existingmore » knowledge on cost-effective retrofits for optimizing distribution in typical multifamily hydronic systems, with the aim of identifying common situations and solutions, and then conducted case studies on two Chicago area buildings with known balancing issues in order to quantify the extent of temperature imbalance. At one of these buildings a booster pump was installed on a loop to an underheated wing of the building. This study found that unit temperature in a multifamily hydronic building can vary as much as 61 degrees F, particularly if windows are opened or tenants use intermittent supplemental heating sources like oven ranges. Average temperature spread at the building as a result of this retrofit decreased from 22.1 degrees F to 15.5 degrees F.« less

Adaptive building skin structures

NASA Astrophysics Data System (ADS)

Del Grosso, A. E.; Basso, P.

2010-12-01

The concept of adaptive and morphing structures has gained considerable attention in the recent years in many fields of engineering. In civil engineering very few practical applications are reported to date however. Non-conventional structural concepts like deployable, inflatable and morphing structures may indeed provide innovative solutions to some of the problems that the construction industry is being called to face. To give some examples, searches for low-energy consumption or even energy-harvesting green buildings are amongst such problems. This paper first presents a review of the above problems and technologies, which shows how the solution to these problems requires a multidisciplinary approach, involving the integration of architectural and engineering disciplines. The discussion continues with the presentation of a possible application of two adaptive and dynamically morphing structures which are proposed for the realization of an acoustic envelope. The core of the two applications is the use of a novel optimization process which leads the search for optimal solutions by means of an evolutionary technique while the compatibility of the resulting configurations of the adaptive envelope is ensured by the virtual force density method.

Evaluation of Automated Model Calibration Techniques for Residential Building Energy Simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robertson, J.; Polly, B.; Collis, J.

2013-09-01

This simulation study adapts and applies the general framework described in BESTEST-EX (Judkoff et al 2010) for self-testing residential building energy model calibration methods. BEopt/DOE-2.2 is used to evaluate four mathematical calibration methods in the context of monthly, daily, and hourly synthetic utility data for a 1960's-era existing home in a cooling-dominated climate. The home's model inputs are assigned probability distributions representing uncertainty ranges, random selections are made from the uncertainty ranges to define 'explicit' input values, and synthetic utility billing data are generated using the explicit input values. The four calibration methods evaluated in this study are: an ASHRAEmore » 1051-RP-based approach (Reddy and Maor 2006), a simplified simulated annealing optimization approach, a regression metamodeling optimization approach, and a simple output ratio calibration approach. The calibration methods are evaluated for monthly, daily, and hourly cases; various retrofit measures are applied to the calibrated models and the methods are evaluated based on the accuracy of predicted savings, computational cost, repeatability, automation, and ease of implementation.« less

Evaluation of Automated Model Calibration Techniques for Residential Building Energy Simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

and Ben Polly, Joseph Robertson; Polly, Ben; Collis, Jon

2013-09-01

This simulation study adapts and applies the general framework described in BESTEST-EX (Judkoff et al 2010) for self-testing residential building energy model calibration methods. BEopt/DOE-2.2 is used to evaluate four mathematical calibration methods in the context of monthly, daily, and hourly synthetic utility data for a 1960's-era existing home in a cooling-dominated climate. The home's model inputs are assigned probability distributions representing uncertainty ranges, random selections are made from the uncertainty ranges to define "explicit" input values, and synthetic utility billing data are generated using the explicit input values. The four calibration methods evaluated in this study are: an ASHRAEmore » 1051-RP-based approach (Reddy and Maor 2006), a simplified simulated annealing optimization approach, a regression metamodeling optimization approach, and a simple output ratio calibration approach. The calibration methods are evaluated for monthly, daily, and hourly cases; various retrofit measures are applied to the calibrated models and the methods are evaluated based on the accuracy of predicted savings, computational cost, repeatability, automation, and ease of implementation.« less

Optimization Based Data Mining Approah for Forecasting Real-Time Energy Demand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Omitaomu, Olufemi A; Li, Xueping; Zhou, Shengchao

The worldwide concern over environmental degradation, increasing pressure on electric utility companies to meet peak energy demand, and the requirement to avoid purchasing power from the real-time energy market are motivating the utility companies to explore new approaches for forecasting energy demand. Until now, most approaches for forecasting energy demand rely on monthly electrical consumption data. The emergence of smart meters data is changing the data space for electric utility companies, and creating opportunities for utility companies to collect and analyze energy consumption data at a much finer temporal resolution of at least 15-minutes interval. While the data granularity providedmore » by smart meters is important, there are still other challenges in forecasting energy demand; these challenges include lack of information about appliances usage and occupants behavior. Consequently, in this paper, we develop an optimization based data mining approach for forecasting real-time energy demand using smart meters data. The objective of our approach is to develop a robust estimation of energy demand without access to these other building and behavior data. Specifically, the forecasting problem is formulated as a quadratic programming problem and solved using the so-called support vector machine (SVM) technique in an online setting. The parameters of the SVM technique are optimized using simulated annealing approach. The proposed approach is applied to hourly smart meters data for several residential customers over several days.« less

Low-Cost Bio-Based Phase Change Materials as an Energy Storage Medium in Building Envelopes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Biswas, Kaushik; Abhari, Mr. Ramin; Shukla, Dr. Nitin

2015-01-01

A promising approach to increasing the energy efficiency of buildings is the implementation of phase change material (PCM) in building envelope systems. Several studies have reported the energy saving potential of PCM in building envelopes. However, wide application of PCMs in building applications has been inhibited, in part, by their high cost. This article describes a novel paraffin product made of naturally occurring fatty acids/glycerides trapped into high density polyethylene (HDPE) pellets and its performance in a building envelope application, with the ultimate goal of commercializing a low-cost PCM platform. The low-cost PCM pellets were mixed with cellulose insulation, installedmore » in external walls and field-tested under natural weatherization conditions for a period of several months. In addition, several PCM samples and PCM-cellulose samples were prepared under controlled conditions for laboratory-scale testing. The laboratory tests were performed to determine the phase change properties of PCM-enhanced cellulose insulation both at microscopic and macroscopic levels. This article presents the data and analysis from the exterior test wall and the laboratory-scale test data. PCM behavior is influenced by the weather and interior conditions, PCM phase change temperature and PCM distribution within the wall cavity, among other factors. Under optimal conditions, the field data showed up to 20% reduction in weekly heat transfer through an external wall due to the PCM compared to cellulose-only insulation.« less

Thermal Energy Storage for Electricity Peak-demand Mitigation: A Solution in Developing and Developed World Alike

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeForest, Nicholas; Mendes, Goncalo; Stadler, Michael

2013-06-02

In much of the developed world, air-conditioning in buildings is the dominant driver of summer peak electricity demand. In the developing world a steadily increasing utilization of air-conditioning places additional strain on already-congested grids. This common thread represents a large and growing threat to the reliable delivery of electricity around the world, requiring capital-intensive expansion of capacity and draining available investment resources. Thermal energy storage (TES), in the form of ice or chilled water, may be one of the few technologies currently capable of mitigating this problem cost effectively and at scale. The installation of TES capacity allows a buildingmore » to meet its on-peak air conditioning load without interruption using electricity purchased off-peak and operating with improved thermodynamic efficiency. In this way, TES has the potential to fundamentally alter consumption dynamics and reduce impacts of air conditioning. This investigation presents a simulation study of a large office building in four distinct geographical contexts: Miami, Lisbon, Shanghai, and Mumbai. The optimization tool DER-CAM (Distributed Energy Resources Customer Adoption Model) is applied to optimally size TES systems for each location. Summer load profiles are investigated to assess the effectiveness and consistency in reducing peak electricity demand. Additionally, annual energy requirements are used to determine system cost feasibility, payback periods and customer savings under local utility tariffs.« less

Integrated Building Energy Systems Design Considering Storage Technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stadler, Michael; Marnay, Chris; Siddiqui, Afzal

The addition of storage technologies such as flow batteries, conventional batteries, and heat storage can improve the economic, as well as environmental attraction of micro-generation systems (e.g., PV or fuel cells with or without CHP) and contribute to enhanced demand response. The interactions among PV, solar thermal, and storage systems can be complex, depending on the tariff structure, load profile, etc. In order to examine the impact of storage technologies on demand response and CO2 emissions, a microgrid's distributed energy resources (DER) adoption problem is formulated as a mixed-integer linear program that can pursue two strategies as its objective function.more » These two strategies are minimization of its annual energy costs or of its CO2 emissions. The problem is solved for a given test year at representative customer sites, e.g., nursing homes, to obtain not only the optimal investment portfolio, but also the optimal hourly operating schedules for the selected technologies. This paper focuses on analysis of storage technologies in micro-generation optimization on a building level, with example applications in New York State and California. It shows results from a two-year research projectperformed for the U.S. Department of Energy and ongoing work. Contrary to established expectations, our results indicate that PV and electric storage adoption compete rather than supplement each other considering the tariff structure and costs of electricity supply. The work shows that high electricity tariffs during on-peak hours are a significant driver for the adoption of electric storage technologies. To satisfy the site's objective of minimizing energy costs, the batteries have to be charged by grid power during off-peak hours instead of PV during on-peak hours. In contrast, we also show a CO2 minimization strategy where the common assumption that batteries can be charged by PV can be fulfilled at extraordinarily high energy costs for the site.« less

Computer modeling of the neurotoxin binding site of acetylcholine receptor spanning residues 185 through 196

NASA Technical Reports Server (NTRS)

Garduno-Juarez, R.; Shibata, M.; Zielinski, T. J.; Rein, R.

1987-01-01

A model of the complex between the acetylcholine receptor and the snake neurotoxin, cobratoxin, was built by molecular model building and energy optimization techniques. The experimentally identified functionally important residues of cobratoxin and the dodecapeptide corresponding to the residues 185-196 of acetylcholine receptor alpha subunit were used to build the model. Both cis and trans conformers of cyclic L-cystine portion of the dodecapeptide were examined. Binding residues independently identified on cobratoxin are shown to interact with the dodecapeptide AChR model.

Systems and methods for energy cost optimization in a building system

DOEpatents

Turney, Robert D.; Wenzel, Michael J.

2016-09-06

Methods and systems to minimize energy cost in response to time-varying energy prices are presented for a variety of different pricing scenarios. A cascaded model predictive control system is disclosed comprising an inner controller and an outer controller. The inner controller controls power use using a derivative of a temperature setpoint and the outer controller controls temperature via a power setpoint or power deferral. An optimization procedure is used to minimize a cost function within a time horizon subject to temperature constraints, equality constraints, and demand charge constraints. Equality constraints are formulated using system model information and system state information whereas demand charge constraints are formulated using system state information and pricing information. A masking procedure is used to invalidate demand charge constraints for inactive pricing periods including peak, partial-peak, off-peak, critical-peak, and real-time.

Simulation model for assessing the efficiency of a combined power installation based on a geothermal heat pump and a vacuum solar collector

NASA Astrophysics Data System (ADS)

Vaysman, Ya I.; Surkov, AA; Surkova, Yu I.; Kychkin, AV

2017-06-01

The article is devoted to the use of renewable energy sources and the assessment of the feasibility of their use in the climatic conditions of the Western Urals. A simulation model that calculates the efficiency of a combined power installations (CPI) was (RES) developed. The CPI consists of the geothermal heat pump (GHP) and the vacuum solar collector (VCS) and is based on the research model. This model allows solving a wide range of problems in the field of energy and resource efficiency, and can be applied to other objects using RES. Based on the research recommendations for optimizing the management and the application of CPI were given. The optimization system will give a positive effect in the energy and resource consumption of low-rise residential buildings projects.

Modeling of District Heating Networks for the Purpose of Operational Optimization with Thermal Energy Storage

NASA Astrophysics Data System (ADS)

Leśko, Michał; Bujalski, Wojciech

2017-12-01

The aim of this document is to present the topic of modeling district heating systems in order to enable optimization of their operation, with special focus on thermal energy storage in the pipelines. Two mathematical models for simulation of transient behavior of district heating networks have been described, and their results have been compared in a case study. The operational optimization in a DH system, especially if this system is supplied from a combined heat and power plant, is a difficult and complicated task. Finding a global financial optimum requires considering long periods of time and including thermal energy storage possibilities into consideration. One of the most interesting options for thermal energy storage is utilization of thermal inertia of the network itself. This approach requires no additional investment, while providing significant possibilities for heat load shifting. It is not feasible to use full topological models of the networks, comprising thousands of substations and network sections, for the purpose of operational optimization with thermal energy storage, because such models require long calculation times. In order to optimize planned thermal energy storage actions, it is necessary to model the transient behavior of the network in a very simple way - allowing for fast and reliable calculations. Two approaches to building such models have been presented. Both have been tested by comparing the results of simulation of the behavior of the same network. The characteristic features, advantages and disadvantages of both kinds of models have been identified. The results can prove useful for district heating system operators in the near future.

Guiding Conformation Space Search with an All-Atom Energy Potential

PubMed Central

Brunette, TJ; Brock, Oliver

2009-01-01

The most significant impediment for protein structure prediction is the inadequacy of conformation space search. Conformation space is too large and the energy landscape too rugged for existing search methods to consistently find near-optimal minima. To alleviate this problem, we present model-based search, a novel conformation space search method. Model-based search uses highly accurate information obtained during search to build an approximate, partial model of the energy landscape. Model-based search aggregates information in the model as it progresses, and in turn uses this information to guide exploration towards regions most likely to contain a near-optimal minimum. We validate our method by predicting the structure of 32 proteins, ranging in length from 49 to 213 amino acids. Our results demonstrate that model-based search is more effective at finding low-energy conformations in high-dimensional conformation spaces than existing search methods. The reduction in energy translates into structure predictions of increased accuracy. PMID:18536015

Modeling and Measurement Constraints in Fault Diagnostics for HVAC Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Najafi, Massieh; Auslander, David M.; Bartlett, Peter L.

2010-05-30

Many studies have shown that energy savings of five to fifteen percent are achievable in commercial buildings by detecting and correcting building faults, and optimizing building control systems. However, in spite of good progress in developing tools for determining HVAC diagnostics, methods to detect faults in HVAC systems are still generally undeveloped. Most approaches use numerical filtering or parameter estimation methods to compare data from energy meters and building sensors to predictions from mathematical or statistical models. They are effective when models are relatively accurate and data contain few errors. In this paper, we address the case where models aremore » imperfect and data are variable, uncertain, and can contain error. We apply a Bayesian updating approach that is systematic in managing and accounting for most forms of model and data errors. The proposed method uses both knowledge of first principle modeling and empirical results to analyze the system performance within the boundaries defined by practical constraints. We demonstrate the approach by detecting faults in commercial building air handling units. We find that the limitations that exist in air handling unit diagnostics due to practical constraints can generally be effectively addressed through the proposed approach.« less

Optimized nested Markov chain Monte Carlo sampling: theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coe, Joshua D; Shaw, M Sam; Sewell, Thomas D

2009-01-01

Metropolis Monte Carlo sampling of a reference potential is used to build a Markov chain in the isothermal-isobaric ensemble. At the endpoints of the chain, the energy is reevaluated at a different level of approximation (the 'full' energy) and a composite move encompassing all of the intervening steps is accepted on the basis of a modified Metropolis criterion. By manipulating the thermodynamic variables characterizing the reference system we maximize the average acceptance probability of composite moves, lengthening significantly the random walk made between consecutive evaluations of the full energy at a fixed acceptance probability. This provides maximally decorrelated samples ofmore » the full potential, thereby lowering the total number required to build ensemble averages of a given variance. The efficiency of the method is illustrated using model potentials appropriate to molecular fluids at high pressure. Implications for ab initio or density functional theory (DFT) treatment are discussed.« less

ATES Smart Grids research project overview and first results

NASA Astrophysics Data System (ADS)

Bloemendal, Martin; Jaxa-Rozen, Marc; Rostampour, Vahab

2016-04-01

Background: ATES is application is growing Application of seasonal Aquifer Thermal Energy Storage (ATES) contributes to energy saving and Greenhouse Gas (GHG)-reduction goals (CBS, 2015; EU, 2010, 2014). Recently it was shown that ATES is applicable in several parts of the world (Bloemendal et al., 2015). While in most parts of the world adoption is just beginning, in the Netherlands progressive building energy efficiency regulation already caused the adoption of ATES to take off (Heekeren and Bakema, 2015; Sommer et al., 2015). As a result of the large number of ATES systems in the Netherlands, the subsurface plays a crucial role in the energy saving objectives of The Netherlands (Kamp, 2015; SER, 2013). Problem: suboptimal use of the subsurface for energy storage ATES systems accumulate in urban areas, as can be expected with a large growth of ATES systems; at many locations in Dutch cities demand for ATES transcends the available space in the subsurface (Li, 2014; Sommer et al., 2015). Within in the Dutch legal framework and state of technology optimal use of the subsurface is not secured; i.e. minimizing the total GHG emissions in a certain area. (Bloemendal et al., 2014; Li, 2014). The most important aspects in this problem are A) the permanent and often unused claim resulting from static permits and B) excessive safety zones around wells to prevent interaction. Both aspects result in an artificial reduction of subsurface space for potential new ATES systems. Recent research has shown that ground energy storage systems could be placed much closer to each other (Bakr et al., 2013; Sommer et al., 2015), and a controlled/limited degree of interaction between them can actually benefit the overall energy savings of an entire area. Solution: the approach and first results of our research project on ATES Smart Grids The heating and cooling demand of buildings is a dynamic and hard to predict process, due to effects such as weather, climate change, changing function and usage of buildings over time. This naturally also applies to the required storage capacity in the subsurface. Because of these uncertainties the only way to optimally use the subsurface is to shift the organization of the subsurface space use from the planning phase to the operational phase. Our solution therefore provides a framework in which adaptability plays a key role. Optimal use can only be achieved when users have insight in the status and their effect on the resource they are exploiting (Ostrom, 1990). Therefore exchange of information is necessary for individual users to adapt their operation based on the current state of the subsurface and their energy demand via a controller and compensation measures. To arrive at a proof-of-concept based on our approach, we use expertise and models from different fields such as administrative policy and decision making, systems and control, and hydrogeology. A central element is the so-called agent-based model (ABM), which is a technique widely used in administrative policy and decision making in order to simulate the behavior of actors. Each agent has a controller that determines how the geothermal energy system must satisfy the energy demand of the building. Thus properties and characteristics of the building and the system are included in this controller. We apply a so-called Model Predictive Control (MPC) approach, which means that the controller takes into account the expected energy demand in the future, and also how its control strategy influences the performance of its own resources. The computed control action is implemented on a groundwater model of the area including all geothermal energy systems, which then serves as the basis for planning the control actions over the next period. This concept is developed in 3 steps up to the scale of a typical Dutch town. Currently we have a proof-of-concept based on a fictitious academic model (1), which we are currently scaling up to the city-center area of Utrecht (2) after which we then incorporate the entire city of Amsterdam (3). The first results of the academic model are promising (Jaxa-Rozen et al., 2015), it shows that stable situations result even for ATES system that are placed a lot closer together than what current regulations would dictate. This has a positive effect on the total GHG emission reduction, but a negative effect on individual efficiency. In the presentation at EGU we will show results from the academic case, discuss several challenges for the optimization and present details on the analytical geohydrological ATES well model required for the controller to keep track of energy losses in its own wells. References • Bakr, M., van Oostrom, N., Sommer, W., 2013. Efficiency of and interference among multiple Aquifer Thermal Energy Storage systems; A Dutch case study. Renewable Energy 60, 53-62. • Bloemendal, M., Olsthoorn, T., Boons, F., 2014. How to achieve optimal and sustainable use of the subsurface for Aquifer Thermal Energy Storage. Energy Policy 66, 104-114. • Bloemendal, M., Olsthoorn, T., van de Ven, F., 2015. Combining climatic and geo-hydrological preconditions as a method to determine world potential for aquifer thermal energy storage. Science of the Total Environment 538 621-633. • CBS, 2015. Hernieuwbare energie in Nederland 2014 (renewable energy in NL). Central authority for statistics in NL, Den Haag. • EU, 2010. Directive on the energy performance of buildings, in: Union, O.J.o.t.E. (Ed.), 153;13-35. EU-Parliament, European Union, Strasbourg. • EU, 2014. A review of factors affecting environmental and economic life-cycle performance for electrically-driven heat pumps, in: Commission, E. (Ed.). • Heekeren, V.v., Bakema, G., 2015. The Netherlands Country Update on Geothermal Energy, World Geothermal Congress, Melbourne. • Jaxa-Rozen, M., Kwakkel, J.H., Bloemendal, M., 2015. The Adoption and Diffusion of Common-Pool Resource-Dependent Technologies: The Case of Aquifer Thermal Energy Storage Systems, PICMET, Portland. • Kamp, H., 2015. Warmtevisie, ministry of economic affairs, Den Haag. • Li, Q., 2014. Optimal use of the subsurface for ATES systems in busy areas, Hydrology. Delft University of Technology, 2014. • Ostrom, E., 1990. Governing the Commons. Cambridge University Press, Camebridge. • SER, 2013. Energie Akkoord. Social economical counsil. • Sommer, W., Valstar, J., Leusbrock, I., Grotenhuis, T., Rijnaarts, H., 2015. Optimization and spatial pattern of large-scale aquifer thermal energy storage. Applied Energy 137, 322-337.

Immunity-Based Optimal Estimation Approach for a New Real Time Group Elevator Dynamic Control Application for Energy and Time Saving

PubMed Central

Baygin, Mehmet; Karakose, Mehmet

2013-01-01

Nowadays, the increasing use of group elevator control systems owing to increasing building heights makes the development of high-performance algorithms necessary in terms of time and energy saving. Although there are many studies in the literature about this topic, they are still not effective enough because they are not able to evaluate all features of system. In this paper, a new approach of immune system-based optimal estimate is studied for dynamic control of group elevator systems. The method is mainly based on estimation of optimal way by optimizing all calls with genetic, immune system and DNA computing algorithms, and it is evaluated with a fuzzy system. The system has a dynamic feature in terms of the situation of calls and the option of the most appropriate algorithm, and it also adaptively works in terms of parameters such as the number of floors and cabins. This new approach which provides both time and energy saving was carried out in real time. The experimental results comparatively demonstrate the effects of method. With dynamic and adaptive control approach in this study carried out, a significant progress on group elevator control systems has been achieved in terms of time and energy efficiency according to traditional methods. PMID:23935433

Advanced Sensors and Controls for Building Applications: Market Assessment and Potential R&D Pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brambley, Michael R.; Haves, Philip; McDonald, Sean C.

2005-04-13

Significant energy savings can be achieved in commercial building operation, along with increased comfort and control for occupants, through the implementation of advanced technologies. This document provides a market assessment of existing building sensors and controls and presents a range of technology pathways (R&D options) for pursuing advanced sensors and building control strategies. This paper is actually a synthesis of five other white papers: the first describes the market assessment including estimates of market potential and energy savings for sensors and control strategies currently on the market as well as a discussion of market barriers to these technologies. The othermore » four cover technology pathways: (1) current applications and strategies for new applications, (2) sensors and controls, (3) networking, security, and protocols and standards, and (4) automated diagnostics, performance monitoring, commissioning, optimal control and tools. Each technology pathway chapter gives an overview of the technology or application. This is followed by a discussion of needs and the current status of the technology. Finally, a series of research topics is proposed.« less

Interstellar Communication Channel Based on a Biological Universal

NASA Technical Reports Server (NTRS)

Weber, Arthur L.; DeVincenzi, Donald L. (Technical Monitor)

1999-01-01

Cellular biosynthesis starts with sugar substrates and continues energetically downhill to yield amino acid, rapid, and nucleotide products. To understand the energetics of these processes, we calculated the energy for biosynthesis from sugars of E. cali's amino acids, nucleotides, and lipids. We found that the biosynthesis of amino acids and lipids from sugar substrates proceeds by redox disproportionation. of sugar carbon with a favorable energy of about -11 kcal/mole of carbon. Overall, redox disproportion of sugar carbon accounted for 84% and 96% (ATP only 6% and 1%) of the total biosynthetic energy of amino acids and lipids (the major cellular constituents). Next, we calculated for all 48 possible 3-carbon substrates the energy of maximal disproportionation to carbon dioxide and methane. We found no other carbon substrates than matched sugars in biosynthetic energy, efficiency, and simplicity. From this, we concluded that sugars are the optimal biosynthetic substrate. Since this conclusion is based on universal properties of carbon chemistry, other carbon-based life throughout the Universe would also use optimal sugar substrates. Furthermore, this rather obvious universal role of sugars as the optimal biosubstrate would probably be common knowledge of technological civilizations throughout the Universe. Since the elemental building block of all sugars is formaldehyde, the common knowledge that sugars are the universal optimal biosubstrate could reasonably lead to the selection of a line(s) in the microwave spectrum of formaldehyde as a frequency for interstellar communication.

SimWIND: A Geospatial Infrastructure Model for Wind Energy Production and Transmission

NASA Astrophysics Data System (ADS)

Middleton, R. S.; Phillips, B. R.; Bielicki, J. M.

2009-12-01

Wind is a clean, enduring energy resource with a capacity to satisfy 20% or more of the electricity needs in the United States. A chief obstacle to realizing this potential is the general paucity of electrical transmission lines between promising wind resources and primary load centers. Successful exploitation of this resource will therefore require carefully planned enhancements to the electric grid. To this end, we present the model SimWIND for self-consistent optimization of the geospatial arrangement and cost of wind energy production and transmission infrastructure. Given a set of wind farm sites that satisfy meteorological viability and stakeholder interest, our model simultaneously determines where and how much electricity to produce, where to build new transmission infrastructure and with what capacity, and where to use existing infrastructure in order to minimize the cost for delivering a given amount of electricity to key markets. Costs and routing of transmission line construction take into account geographic and social factors, as well as connection and delivery expenses (transformers, substations, etc.). We apply our model to Texas and consider how findings complement the 2008 Electric Reliability Council of Texas (ERCOT) Competitive Renewable Energy Zones (CREZ) Transmission Optimization Study. Results suggest that integrated optimization of wind energy infrastructure and cost using SimWIND could play a critical role in wind energy planning efforts.

Aerodynamics of Ventilation in Termite Mounds

NASA Astrophysics Data System (ADS)

Bailoor, Shantanu; Yaghoobian, Neda; Turner, Scott; Mittal, Rajat

2017-11-01

Fungus-cultivating termites collectively build massive, complex mounds which are much larger than the size of an individual termite and effectively use natural wind and solar energy, as well as the energy generated by the colony's own metabolic activity to maintain the necessary environmental condition for the colony's survival. We seek to understand the aerodynamics of ventilation and thermoregulation of termite mounds through computational modeling. A simplified model accounting for key mound features, such as soil porosity and internal conduit network, is subjected to external draft conditions. The role of surface flow conditions in the generation of internal flow patterns and the ability of the mound to transport gases and heat from the nursery are examined. The understanding gained from our study could be used to guide sustainable bio-inspired passive HVAC system design, which could help optimize energy utilization in commercial and residential buildings. This research is supported by a seed Grant from the Environment, Energy Sustainability and Health Institute of the Johns Hopkins University.

A method to optimize the shield compact and lightweight combining the structure with components together by genetic algorithm and MCNP code.

PubMed

Cai, Yao; Hu, Huasi; Pan, Ziheng; Hu, Guang; Zhang, Tao

2018-05-17

To optimize the shield for neutrons and gamma rays compact and lightweight, a method combining the structure and components together was established employing genetic algorithms and MCNP code. As a typical case, the fission energy spectrum of 235 U which mixed neutrons and gamma rays was adopted in this study. Six types of materials were presented and optimized by the method. Spherical geometry was adopted in the optimization after checking the geometry effect. Simulations have made to verify the reliability of the optimization method and the efficiency of the optimized materials. To compare the materials visually and conveniently, the volume and weight needed to build a shield are employed. The results showed that, the composite multilayer material has the best performance. Copyright © 2018 Elsevier Ltd. All rights reserved.

Optimal angle of polycrystalline silicon solar panels placed in a building using the ant colony optimization algorithm

NASA Astrophysics Data System (ADS)

Saouane, I.; Chaker, A.; Zaidi, B.; Shekhar, C.

2017-03-01

This paper describes the mathematical model used to determine the amount of solar radiation received on an inclined solar photovoltaic panel. The optimum slope angles for each month, season, and year have also been calculated for a solar photovoltaic panel. The optimization of the procedure to maximize the solar energy collected by the solar panel by varying the tilt angle is also presented. As a first step, the global solar radiation on the horizontal surface of a thermal photovoltaic panel during clear sky is estimated. Thereafter, the Muneer model, which provides the most accurate estimation of the total solar radiation at a given geographical point has been used to determine the optimum collector slope. Also, the Ant Colony Optimization (ACO) algorithm was applied to obtain the optimum tilt angle settings for PV collector to improve the PV collector efficiency. The results show good agreement between calculated and predicted results. Additionally, this paper presents studies carried out on the polycrystalline silicon solar panels for electrical energy generation in the city of Ghardaia. The electrical energy generation has been studied as a function of amount of irradiation received and the angle of optimum orientation of the solar panels.

Optimal PGU operation strategy in CHP systems

NASA Astrophysics Data System (ADS)

Yun, Kyungtae

Traditional power plants only utilize about 30 percent of the primary energy that they consume, and the rest of the energy is usually wasted in the process of generating or transmitting electricity. On-site and near-site power generation has been considered by business, labor, and environmental groups to improve the efficiency and the reliability of power generation. Combined heat and power (CHP) systems are a promising alternative to traditional power plants because of the high efficiency and low CO2 emission achieved by recovering waste thermal energy produced during power generation. A CHP operational algorithm designed to optimize operational costs must be relatively simple to implement in practice such as to minimize the computational requirements from the hardware to be installed. This dissertation focuses on the following aspects pertaining the design of a practical CHP operational algorithm designed to minimize the operational costs: (a) real-time CHP operational strategy using a hierarchical optimization algorithm; (b) analytic solutions for cost-optimal power generation unit operation in CHP Systems; (c) modeling of reciprocating internal combustion engines for power generation and heat recovery; (d) an easy to implement, effective, and reliable hourly building load prediction algorithm.

A seismic optimization procedure for reinforced concrete framed buildings based on eigenfrequency optimization

NASA Astrophysics Data System (ADS)

Arroyo, Orlando; Gutiérrez, Sergio

2017-07-01

Several seismic optimization methods have been proposed to improve the performance of reinforced concrete framed (RCF) buildings; however, they have not been widely adopted among practising engineers because they require complex nonlinear models and are computationally expensive. This article presents a procedure to improve the seismic performance of RCF buildings based on eigenfrequency optimization, which is effective, simple to implement and efficient. The method is used to optimize a 10-storey regular building, and its effectiveness is demonstrated by nonlinear time history analyses, which show important reductions in storey drifts and lateral displacements compared to a non-optimized building. A second example for an irregular six-storey building demonstrates that the method provides benefits to a wide range of RCF structures and supports the applicability of the proposed method.

Haiti: Feasibility of Waste-to-Energy Options at the Trutier Waste Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Conrad, M. D.; Hunsberger, R.; Ness, J. E.

2014-08-01

This report provides further analysis of the feasibility of a waste-to-energy (WTE) facility in the area near Port-au-Prince, Haiti. NREL's previous analysis and reports identified anaerobic digestion (AD) as the optimal WTE technology at the facility. Building on the prior analyses, this report evaluates the conceptual financial and technical viability of implementing a combined waste management and electrical power production strategy by constructing a WTE facility at the existing Trutier waste site north of Port-au-Prince.

Energy Optimization Assessments at U.S. Army Installations: Caserma Ederle Vicenza, Italy

DTIC Science & Technology

2009-01-17

Caserma Ederle has one central plant, described in ECM CEP #2. In addi- tion to looking at the planned renovation of the central plant, this study...serving Bldgs 10B, 23, 44 and 66 • east circuit serving Bldg 290 (New Commissary building). The north circuit was recently renovated . Up to the New...water lines as a primary system for the hot water generators. New central plant concept The existing Central Energy Plant is going to be renovated by

Chapter 16: Retrocommissioning Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurnik, Charles W.; Tiessen, Alex

Retrocommissioning (RCx) is a systematic process for optimizing energy performance in existing buildings. It specifically focuses on improving the control of energy-using equipment (e.g., heating, ventilation, and air conditioning [HVAC] equipment and lighting) and typically does not involve equipment replacement. Field results have shown proper RCx can achieve energy savings ranging from 5 percent to 20 percent, with a typical payback of two years or less (Thorne 2003). The method presented in this protocol provides direction regarding: (1) how to account for each measure's specific characteristics and (2) how to choose the most appropriate savings verification approach.

Advanced sorting technologies for optimal wood products and woody biomass utilization

Treesearch

Xiping Wang

2012-01-01

Forest materials represent great potential for advancing our goals in the 21st century for sustainable building, energy independence, and carbon sequestration. A critical component of an improved system for producing bioproducts and bioenergr from forest materials is the ability to sort trees, stems, and logs into end-product categories that represent their highest...

Energy management and control of active distribution systems

NASA Astrophysics Data System (ADS)

Shariatzadeh, Farshid

Advancements in the communication, control, computation and information technologies have driven the transition to the next generation active power distribution systems. Novel control techniques and management strategies are required to achieve the efficient, economic and reliable grid. The focus of this work is energy management and control of active distribution systems (ADS) with integrated renewable energy sources (RESs) and demand response (DR). Here, ADS mean automated distribution system with remotely operated controllers and distributed energy resources (DERs). DER as active part of the next generation future distribution system includes: distributed generations (DGs), RESs, energy storage system (ESS), plug-in hybrid electric vehicles (PHEV) and DR. Integration of DR and RESs into ADS is critical to realize the vision of sustainability. The objective of this dissertation is the development of management architecture to control and operate ADS in the presence of DR and RES. One of the most challenging issues for operating ADS is the inherent uncertainty of DR and RES as well as conflicting objective of DER and electric utilities. ADS can consist of different layers such as system layer and building layer and coordination between these layers is essential. In order to address these challenges, multi-layer energy management and control architecture is proposed with robust algorithms in this work. First layer of proposed multi-layer architecture have been implemented at the system layer. Developed AC optimal power flow (AC-OPF) generates fair price for all DR and non-DR loads which is used as a control signal for second layer. Second layer controls DR load at buildings using a developed look-ahead robust controller. Load aggregator collects information from all buildings and send aggregated load to the system optimizer. Due to the different time scale at these two management layers, time coordination scheme is developed. Robust and deterministic controllers are developed to maximize the energy usage from rooftop photovoltaic (PV) generation locally and minimize heat-ventilation and air conditioning (HVAC) consumption while maintaining inside temperature within comfort zone. The performance of the developed multi-layer architecture has been analyzed using test case studies and results show the robustness of developed controller in the presence of uncertainty.

Air condition sensor on KNX network

NASA Astrophysics Data System (ADS)

Gecova, Katerina; Vala, David; Slanina, Zdenek; Walendziuk, Wojciech

2017-08-01

One of the main goals of modern buildings in addition to the management environment is also attempt to save energy. For this reason, increased demands on the prevention of energy loss, which can be expressed for example as an inefficient use of the available functions as a building or heat leakage. Reducing heat loss as a perfect tightness of doors and windows in the building, however, restricts the natural ventilation, which leads to a gradual deterioration of the quality of the internal environment. This state then has a very significant impact on human health. In the closed, poorly ventilated area, the person staying at increasing the carbon dioxide concentration, temperature and humidity, which impacts the human thermoregulation system, increases fatigue and causes restlessness. It is therefore necessary to monitor these parameters and then control so as to ensure stable and optimal human values. The aim is to design and implementation Module sensors that will be able to measure different parameters, allowing the subsequent regulation of indoor environmental quality.

A web-based Decision Support System for the optimal management of construction and demolition waste.

PubMed

Banias, G; Achillas, Ch; Vlachokostas, Ch; Moussiopoulos, N; Papaioannou, I

2011-12-01

Wastes from construction activities constitute nowadays the largest by quantity fraction of solid wastes in urban areas. In addition, it is widely accepted that the particular waste stream contains hazardous materials, such as insulating materials, plastic frames of doors, windows, etc. Their uncontrolled disposal result to long-term pollution costs, resource overuse and wasted energy. Within the framework of the DEWAM project, a web-based Decision Support System (DSS) application - namely DeconRCM - has been developed, aiming towards the identification of the optimal construction and demolition waste (CDW) management strategy that minimises end-of-life costs and maximises the recovery of salvaged building materials. This paper addresses both technical and functional structure of the developed web-based application. The web-based DSS provides an accurate estimation of the generated CDW quantities of twenty-one different waste streams (e.g. concrete, bricks, glass, etc.) for four different types of buildings (residential, office, commercial and industrial). With the use of mathematical programming, the DeconRCM provides also the user with the optimal end-of-life management alternative, taking into consideration both economic and environmental criteria. The DSS's capabilities are illustrated through a real world case study of a typical five floor apartment building in Thessaloniki, Greece. Copyright © 2011 Elsevier Ltd. All rights reserved.

Charging power optimization for nonlinear vibration energy harvesting systems subjected to arbitrary, persistent base excitations

NASA Astrophysics Data System (ADS)

Dai, Quanqi; Harne, Ryan L.

2018-01-01

The vibrations of mechanical systems and structures are often a combination of periodic and random motions. Emerging interest to exploit nonlinearities in vibration energy harvesting systems for charging microelectronics may be challenged by such reality due to the potential to transition between favorable and unfavorable dynamic regimes for DC power delivery. Therefore, a need exists to devise an optimization method whereby charging power from nonlinear energy harvesters remains maximized when excitation conditions are neither purely harmonic nor purely random, which have been the attention of past research. This study meets the need by building from an analytical approach that characterizes the dynamic response of nonlinear energy harvesting platforms subjected to combined harmonic and stochastic base accelerations. Here, analytical expressions are formulated and validated to optimize charging power while the influences of the relative proportions of excitation types are concurrently assessed. It is found that about a 2 times deviation in optimal resistive loads can reduce the charging power by 20% when the system is more prominently driven by harmonic base accelerations, whereas a greater proportion of stochastic excitation results in a 11% reduction in power for the same resistance deviation. In addition, the results reveal that when the frequency of a predominantly harmonic excitation deviates by 50% from optimal conditions the charging power reduces by 70%, whereas the same frequency deviation for a more stochastically dominated excitation reduce total DC power by only 20%. These results underscore the need for maximizing direct current power delivery for nonlinear energy harvesting systems in practical operating environments.

Impact of Sustainable Cool Roof Technology on Building Energy Consumption

NASA Astrophysics Data System (ADS)

Vuppuluri, Prem Kiran

Highly reflective roofing systems have been analyzed over several decades to evaluate their ability to meet sustainability goals, including reducing building energy consumption and mitigating the urban heat island. Studies have isolated and evaluated the effects of climate, surface reflectivity, and roof insulation on energy savings, thermal load mitigation and also ameliorating the urban heat island. Other sustainable roofing systems, like green-roofs and solar panels have been similarly evaluated. The motivation for the present study is twofold: the first goal is to present a method for simultaneous evaluation and inter-comparison of multiple roofing systems, and the second goal is to quantitatively evaluate the realized heating and cooling energy savings associated with a white roof system compared to the reduction in roof-top heat flux. To address the first research goal a field experiment was conducted at the International Harvester Building located in Portland, OR. Thermal data was collected for a white roof, vegetated roof, and a solar panel shaded vegetated roof, and the heat flux through these roofing systems was compared against a control patch of conventional dark roof membrane. The second research goal was accomplished using a building energy simulation program to determine the impact of roof area and roof insulation on the savings from a white roof, in both Portland and Phoenix. The ratio of cooling energy savings to roof heat flux reduction from replacing a dark roof with a white roof was 1:4 for the month of July, and 1:5 annually in Portland. The COP of the associated chillers ranges from 2.8-4.2, indicating that the ratio of cooling energy savings to heat flux reduction is not accounted for solely by the COP of the chillers. The results of the building simulation indicate that based on energy savings alone, white roofs are not an optimal choice for Portland. The benefits associated with cooling energy savings relative to a black roof are offset by the winter-time penalty, and the net benefit from adopting white roof technology in Portland is small. That said, there are other potential benefits of white roofing such as impact on urban heat islands and roof life that must also be considered.

Research on Optimal Observation Scale for Damaged Buildings after Earthquake Based on Optimal Feature Space

NASA Astrophysics Data System (ADS)

Chen, J.; Chen, W.; Dou, A.; Li, W.; Sun, Y.

2018-04-01

A new information extraction method of damaged buildings rooted in optimal feature space is put forward on the basis of the traditional object-oriented method. In this new method, ESP (estimate of scale parameter) tool is used to optimize the segmentation of image. Then the distance matrix and minimum separation distance of all kinds of surface features are calculated through sample selection to find the optimal feature space, which is finally applied to extract the image of damaged buildings after earthquake. The overall extraction accuracy reaches 83.1 %, the kappa coefficient 0.813. The new information extraction method greatly improves the extraction accuracy and efficiency, compared with the traditional object-oriented method, and owns a good promotional value in the information extraction of damaged buildings. In addition, the new method can be used for the information extraction of different-resolution images of damaged buildings after earthquake, then to seek the optimal observation scale of damaged buildings through accuracy evaluation. It is supposed that the optimal observation scale of damaged buildings is between 1 m and 1.2 m, which provides a reference for future information extraction of damaged buildings.

Simulation of value stream mapping and discrete optimization of energy consumption in modular construction

NASA Astrophysics Data System (ADS)

Chowdhury, Md Mukul

With the increased practice of modularization and prefabrication, the construction industry gained the benefits of quality management, improved completion time, reduced site disruption and vehicular traffic, and improved overall safety and security. Whereas industrialized construction methods, such as modular and manufactured buildings, have evolved over decades, core techniques used in prefabrication plants vary only slightly from those employed in traditional site-built construction. With a focus on energy and cost efficient modular construction, this research presents the development of a simulation, measurement and optimization system for energy consumption in the manufacturing process of modular construction. The system is based on Lean Six Sigma principles and loosely coupled system operation to identify the non-value adding tasks and possible causes of low energy efficiency. The proposed system will also include visualization functions for demonstration of energy consumption in modular construction. The benefits of implementing this system include a reduction in the energy consumption in production cost, decrease of energy cost in the production of lean-modular construction, and increase profit. In addition, the visualization functions will provide detailed information about energy efficiency and operation flexibility in modular construction. A case study is presented to validate the reliability of the system.

Passivhaus: indoor comfort and energy dynamic analysis.

NASA Astrophysics Data System (ADS)

Guida, Antonella; Pagliuca, Antonello; Cardinale, Nicola; Rospi, Gianluca

2013-04-01

The research aims to verify the energy performance as well as the indoor comfort of an energy class A+ building, built so that the sum of the heat passive contributions of solar radiation, transmitted through the windows, and the heat generated inside the building, are adeguate to compensate for the envelope loss during the cold season. The building, located in Emilia Romagna (Italy), was built using a wooden structure, an envelope realized using a pinewood sandwich panels (transmittance U = 0.250 W/m2K) and, inside, a wool flax insulation layer and thermal window frame with low-emissivity glass (U = 0524 W/m2K). The building design and construction process has followed the guidelines set by "CasaClima". The building has been modeled in the code of dynamic calculation "Energy Plus" by the Design Builder application and divided it into homogenous thermal zones, characterized by winter indoor temperature set at 20 ° (+ / - 1 °) and summer indoor temperature set at 26 ° (+ / - 1 °). It has modeled: the envelope, as described above, the "free" heat contributions, the air conditioning system, the Mechanical Ventilation system as well as home automation solutions. The air conditioning system is an heat pump, able to guarantee an optimization of energy consumption (in fact, it uses the "free" heat offered by the external environment for conditioning indoor environment). As regards the air recirculation system, it has been used a mechanical ventilation system with internal heat cross-flow exchanger, with an efficiency equal to 50%. The domotic solutions, instead, regard a system for the control of windows external screening using reeds, adjustable as a function of incident solar radiation and a lighting management system adjusted automatically using a dimmer. A so realized building meets the requirement imposed from Italian standard UNI/TS 11300 1, UNI/TS 11300 2 and UNI/TS 11300 3. The analysis was performed according to two different configurations: in "spontaneous-state analysis" (that provides the only energy performance of the structure) and considering the "building-equipments" as a system (which provides the overall performance of the "building system"). The first analysis shows as the absence of thermal mass and the envelope super-heating prevent to incoming heat to exit, overheating the indoor environment. The analysis of the overall performance of the "building system" highlights, instead, as the thermal load is much greater during the summer than in winter; this means that, using a low inertia envelopes, the energy saved in the winter can be used to satisfy the thermal performance in the summer. This is further demonstrated by comparing the performance of indoor temperatures and the relative energy consumption of a similar building with greater thermal inertia. Further analysis involved a critical comparison between the "semisteady-state analysis" ("CasaClima" methodology) and the analysis in dynamic conditions (using "Energy Plus" software).

Foresee: A user-centric home energy management system for energy efficiency and demand response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Xin; Baker, Kyri A.; Christensen, Dane T.

This paper presents foresee, a user-centric home energy management system that can help optimize how a home operates to concurrently meet users' needs, achieve energy efficiency and commensurate utility cost savings, and reliably deliver grid services based on utility signals. Foresee is built on a multiobjective model predictive control framework, wherein the objectives consist of energy cost, thermal comfort, user convenience, and carbon emission. Foresee learns user preferences on different objectives and acts on their behalf to operate building equipment, such as home appliances, photovoltaic systems, and battery storage. In this work, machine-learning algorithms were used to derive data-driven appliancemore » models and usage patterns to predict the home's future energy consumption. This approach enables highly accurate predictions of comfort needs, energy costs, environmental impacts, and grid service availability. Simulation studies were performed on field data from a residential building stock data set collected in the Pacific Northwest. Results indicated that foresee generated up to 7.6% whole-home energy savings without requiring substantial behavioral changes. When responding to demand response events, foresee was able to provide load forecasts upon receipt of event notifications and delivered the committed demand response services with 10% or fewer errors. Foresee fully utilized the potential of the battery storage and controllable building loads and delivered up to 7.0-kW load reduction and 13.5-kW load increase. As a result, these benefits are provided while maintaining the occupants' thermal comfort or convenience in using their appliances.« less

Foresee: A user-centric home energy management system for energy efficiency and demand response

DOE PAGES

Jin, Xin; Baker, Kyri A.; Christensen, Dane T.; ...

2017-08-23

This paper presents foresee, a user-centric home energy management system that can help optimize how a home operates to concurrently meet users' needs, achieve energy efficiency and commensurate utility cost savings, and reliably deliver grid services based on utility signals. Foresee is built on a multiobjective model predictive control framework, wherein the objectives consist of energy cost, thermal comfort, user convenience, and carbon emission. Foresee learns user preferences on different objectives and acts on their behalf to operate building equipment, such as home appliances, photovoltaic systems, and battery storage. In this work, machine-learning algorithms were used to derive data-driven appliancemore » models and usage patterns to predict the home's future energy consumption. This approach enables highly accurate predictions of comfort needs, energy costs, environmental impacts, and grid service availability. Simulation studies were performed on field data from a residential building stock data set collected in the Pacific Northwest. Results indicated that foresee generated up to 7.6% whole-home energy savings without requiring substantial behavioral changes. When responding to demand response events, foresee was able to provide load forecasts upon receipt of event notifications and delivered the committed demand response services with 10% or fewer errors. Foresee fully utilized the potential of the battery storage and controllable building loads and delivered up to 7.0-kW load reduction and 13.5-kW load increase. As a result, these benefits are provided while maintaining the occupants' thermal comfort or convenience in using their appliances.« less

Wilson Dslash Kernel From Lattice QCD Optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joo, Balint; Smelyanskiy, Mikhail; Kalamkar, Dhiraj D.

2015-07-01

Lattice Quantum Chromodynamics (LQCD) is a numerical technique used for calculations in Theoretical Nuclear and High Energy Physics. LQCD is traditionally one of the first applications ported to many new high performance computing architectures and indeed LQCD practitioners have been known to design and build custom LQCD computers. Lattice QCD kernels are frequently used as benchmarks (e.g. 168.wupwise in the SPEC suite) and are generally well understood, and as such are ideal to illustrate several optimization techniques. In this chapter we will detail our work in optimizing the Wilson-Dslash kernels for Intel Xeon Phi, however, as we will show themore » technique gives excellent performance on regular Xeon Architecture as well.« less

Correlations between Climate Change and the Modern European Construction

NASA Astrophysics Data System (ADS)

Gumińska, Anna

2017-10-01

The aim of the study was to analyze the links between climate change and the way modern cities are structured and responded to climate change. How do these changes affect building materials and technologies, or does climate change affect the type of technology and materials used? The most important results are the effects of analysing selected examples of a modern European building, the use of materials and technology, the adaptation of buildings to the changing climate. Selected examples of contemporary architecture from Germany, Italy and Denmark, Norway and Sweden. There are also examples in photographic documentation. The most important criteria affecting the objects are elements that shape the changing climate, as well as existing legal and technical requirements. The main conclusion was that modern urban space is adapted to the changing climate. Unprecedented climatic phenomena in this area: intense and sudden rain, snow, floods, strong winds, abundant sunshine, high temperature changes, greenhouse effect of the city - “island heat”, atmospheric pollution. Building materials and technologies contribute to the optimal conservation of natural resources, buildings are shaped in such a way as to ensure safety, resilience and environmental protection. However, there is still a need for continuous monitoring of climate change, criteria affecting the design and construction of urban and central facilities. Key words: energy efficiency, renewable energy, climate change, contemporary architecture.

Multi-level, Multi-stage and Stochastic Optimization Models for Energy Conservation in Buildings for Federal, State and Local Agencies

NASA Astrophysics Data System (ADS)

Champion, Billy Ray

Energy Conservation Measure (ECM) project selection is made difficult given real-world constraints, limited resources to implement savings retrofits, various suppliers in the market and project financing alternatives. Many of these energy efficient retrofit projects should be viewed as a series of investments with annual returns for these traditionally risk-averse agencies. Given a list of ECMs available, federal, state and local agencies must determine how to implement projects at lowest costs. The most common methods of implementation planning are suboptimal relative to cost. Federal, state and local agencies can obtain greater returns on their energy conservation investment over traditional methods, regardless of the implementing organization. This dissertation outlines several approaches to improve the traditional energy conservations models. . Any public buildings in regions with similar energy conservation goals in the United States or internationally can also benefit greatly from this research. Additionally, many private owners of buildings are under mandates to conserve energy e.g., Local Law 85 of the New York City Energy Conservation Code requires any building, public or private, to meet the most current energy code for any alteration or renovation. Thus, both public and private stakeholders can benefit from this research. . The research in this dissertation advances and presents models that decision-makers can use to optimize the selection of ECM projects with respect to the total cost of implementation. A practical application of a two-level mathematical program with equilibrium constraints (MPEC) improves the current best practice for agencies concerned with making the most cost-effective selection leveraging energy services companies or utilities. The two-level model maximizes savings to the agency and profit to the energy services companies (Chapter 2). An additional model presented leverages a single congressional appropriation to implement ECM projects (Chapter 3). Returns from implemented ECM projects are used to fund additional ECM projects. In these cases, fluctuations in energy costs and uncertainty in the estimated savings severely influence ECM project selection and the amount of the appropriation requested. A risk aversion method proposed imposes a minimum on the number of "of projects completed in each stage. A comparative method using Conditional Value at Risk is analyzed. Time consistency was addressed in this chapter. This work demonstrates how a risk-based, stochastic, multi-stage model with binary decision variables at each stage provides a much more accurate estimate for planning than the agency's traditional approach and deterministic models. Finally, in Chapter 4, a rolling-horizon model allows for subadditivity and superadditivity of the energy savings to simulate interactive effects between ECM projects. The approach makes use of inequalities (McCormick, 1976) to re-express constraints that involve the product of binary variables with an exact linearization (related to the convex hull of those constraints). This model additionally shows the benefits of learning between stages while remaining consistent with the single congressional appropriations framework.

Dynamic modeling, experimental evaluation, optimal design and control of integrated fuel cell system and hybrid energy systems for building demands

NASA Astrophysics Data System (ADS)

Nguyen, Gia Luong Huu

Fuel cells can produce electricity with high efficiency, low pollutants, and low noise. With the advent of fuel cell technologies, fuel cell systems have since been demonstrated as reliable power generators with power outputs from a few watts to a few megawatts. With proper equipment, fuel cell systems can produce heating and cooling, thus increased its overall efficiency. To increase the acceptance from electrical utilities and building owners, fuel cell systems must operate more dynamically and integrate well with renewable energy resources. This research studies the dynamic performance of fuel cells and the integration of fuel cells with other equipment in three levels: (i) the fuel cell stack operating on hydrogen and reformate gases, (ii) the fuel cell system consisting of a fuel reformer, a fuel cell stack, and a heat recovery unit, and (iii) the hybrid energy system consisting of photovoltaic panels, fuel cell system, and energy storage. In the first part, this research studied the steady-state and dynamic performance of a high temperature PEM fuel cell stack. Collaborators at Aalborg University (Aalborg, Denmark) conducted experiments on a high temperature PEM fuel cell short stack at steady-state and transients. Along with the experimental activities, this research developed a first-principles dynamic model of a fuel cell stack. The dynamic model developed in this research was compared to the experimental results when operating on different reformate concentrations. Finally, the dynamic performance of the fuel cell stack for a rapid increase and rapid decrease in power was evaluated. The dynamic model well predicted the performance of the well-performing cells in the experimental fuel cell stack. The second part of the research studied the dynamic response of a high temperature PEM fuel cell system consisting of a fuel reformer, a fuel cell stack, and a heat recovery unit with high thermal integration. After verifying the model performance with the obtained experimental data, the research studied the control of airflow to regulate the temperature of reactors within the fuel processor. The dynamic model provided a platform to test the dynamic response for different control gains. With sufficient sensing and appropriate control, a rapid response to maintain the temperature of the reactor despite an increase in power was possible. The third part of the research studied the use of a fuel cell in conjunction with photovoltaic panels, and energy storage to provide electricity for buildings. This research developed an optimization framework to determine the size of each device in the hybrid energy system to satisfy the electrical demands of buildings and yield the lowest cost. The advantage of having the fuel cell with photovoltaic and energy storage was the ability to operate the fuel cell at baseload at night, thus reducing the need for large battery systems to shift the solar power produced in the day to the night. In addition, the dispatchability of the fuel cell provided an extra degree of freedom necessary for unforeseen disturbances. An operation framework based on model predictive control showed that the method is suitable for optimizing the dispatch of the hybrid energy system.

Study on the design schemes of the air-conditioning system in a gymnasium

NASA Astrophysics Data System (ADS)

Zhang, Yujin; Wu, Xinwei; Zhang, Jing; Pan, Zhixin

2017-08-01

In view of designing the air conditioning project for a gymnasium successfully, the cooling and heating source schemes are fully studied by analyzing the surrounding environment and energy conditions of the project, as well as the analysis of the initial investment and operating costs, which indicates the air source heat pump air conditioning system is the best choice for the project. The indoor air conditioning schemes are also studied systematically and the optimization of air conditioning schemes is carried out in each area. The principle of operating conditions for the whole year is followed and the quality of indoor air and energy-saving are ensured by the optimized design schemes, which provide references for the air conditioning system design in the same kinds of building.

Statistical Analysis of Solar PV Power Frequency Spectrum for Optimal Employment of Building Loads

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olama, Mohammed M; Sharma, Isha; Kuruganti, Teja

In this paper, a statistical analysis of the frequency spectrum of solar photovoltaic (PV) power output is conducted. This analysis quantifies the frequency content that can be used for purposes such as developing optimal employment of building loads and distributed energy resources. One year of solar PV power output data was collected and analyzed using one-second resolution to find ideal bounds and levels for the different frequency components. The annual, seasonal, and monthly statistics of the PV frequency content are computed and illustrated in boxplot format. To examine the compatibility of building loads for PV consumption, a spectral analysis ofmore » building loads such as Heating, Ventilation and Air-Conditioning (HVAC) units and water heaters was performed. This defined the bandwidth over which these devices can operate. Results show that nearly all of the PV output (about 98%) is contained within frequencies lower than 1 mHz (equivalent to ~15 min), which is compatible for consumption with local building loads such as HVAC units and water heaters. Medium frequencies in the range of ~15 min to ~1 min are likely to be suitable for consumption by fan equipment of variable air volume HVAC systems that have time constants in the range of few seconds to few minutes. This study indicates that most of the PV generation can be consumed by building loads with the help of proper control strategies, thereby reducing impact on the grid and the size of storage systems.« less

Spectroscopic investigation of some building blocks of organic conductors: A comparative study

NASA Astrophysics Data System (ADS)

Mukherjee, V.; Yadav, T.

2017-04-01

Theoretical molecular structures and IR and Raman spectra of di and tetra methyl substituted tetrathiafulvalene and tetraselenafulvalene molecules have been studied. These molecules belong to the organic conductor family and are immensely used as building blocks of several organic conducting devices. The Hartree-Fock and density functional theory with exchange functional B3LYP have been employed for computational purpose. We have also performed normal coordinate analysis to scale the theoretical frequencies and to calculate potential energy distributions for the conspicuous assignments. The exciting frequency and temperature dependent Raman spectra have also presented. Optimization results reveal that the sulphur derivatives possess boat shape while selenium derivatives possess planner structures. Natural bond orbitals analysis has also been performed to study second order interaction between donors and acceptors and to compute molecular orbital occupancy and energy.

Stochastic modelling of temperatures affecting the in situ performance of a solar-assisted heat pump: The multivariate approach and physical interpretation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loveday, D.L.; Craggs, C.

Box-Jenkins-based multivariate stochastic modeling is carried out using data recorded from a domestic heating system. The system comprises an air-source heat pump sited in the roof space of a house, solar assistance being provided by the conventional tile roof acting as a radiation absorber. Multivariate models are presented which illustrate the time-dependent relationships between three air temperatures - at external ambient, at entry to, and at exit from, the heat pump evaporator. Using a deterministic modeling approach, physical interpretations are placed on the results of the multivariate technique. It is concluded that the multivariate Box-Jenkins approach is a suitable techniquemore » for building thermal analysis. Application to multivariate Box-Jenkins approach is a suitable technique for building thermal analysis. Application to multivariate model-based control is discussed, with particular reference to building energy management systems. It is further concluded that stochastic modeling of data drawn from a short monitoring period offers a means of retrofitting an advanced model-based control system in existing buildings, which could be used to optimize energy savings. An approach to system simulation is suggested.« less

Energy Optimization Assessment at U.S. Army Installations: Fort Bliss, TX

DTIC Science & Technology

2008-09-01

that if implemented would reduce Fort Bliss’s annual energy use by up to 65 MWH/yr electric and 170,023 MMBtu/yr thermal savings (mostly natural gas...solar heating for domestic hot water at selected buildings 0 0 $— 6040 $— $— $— $— 0.0 HVAC #3 Replace warm air heating system in vehicle...HVAC #6* Replace existing boilers with high- efficiency boilers 0 0 0 4,591 41,708 4,250 45,958 267,781 5.8 HVAC #7* Replace existing heating and

Biorthogonal projected energies of a Gutzwiller similarity transformed Hamiltonian.

PubMed

Wahlen-Strothman, J M; Scuseria, G E

2016-12-07

We present a method incorporating biorthogonal orbital-optimization, symmetry projection, and double-occupancy screening with a non-unitary similarity transformation generated by the Gutzwiller factor [Formula: see text], and apply it to the Hubbard model. Energies are calculated with mean-field computational scaling with high-quality results comparable to coupled cluster singles and doubles. This builds on previous work performing similarity transformations with more general, two-body Jastrow-style correlators. The theory is tested on 2D lattices ranging from small systems into the thermodynamic limit and is compared to available reference data.

Sun/Earth: how to use solar and climatic energies today

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crowther, R.L.

1976-01-01

This book graphically presents many concepts that are cost-effective today for the utilization of free natural energy sources in homes and other buildings. All of the natural energy concepts presented are in a process of continuing development. Many of them are immediately economic and practical, while some are not. It takes the application of money to construct devices to harness natural energy or to construct energy efficient forms of architecture. In numerous cases operational energy is not required to employ the Sun, wind, water, and Earth as free anti-inflationary energy sources. In other cases a very small input of operationalmore » energy in comparison to the total energy output is required. All land and buildings are solar collectors. The problem is how to cost effectively make them efficient collectors of solar radiation in winter and how to use natural forms of energy to cool and ventilate them during summer and other seasons of the year. Regional and microclimatic conditions vary throughout the world. Topography and landscaping can play an important role in climatic control and climatic effect upon architecture. The examples presented for optimized energy conservation and solar active and passive systems are generic to most northern latitudes, but need modification or adaption to specific locations and climates. An annotated bibliography, containing additional reference, is included.« less

Methods for Analysis of Urban Energy Systems: A New York City Case Study

NASA Astrophysics Data System (ADS)

Howard, Bianca

This dissertation describes methods developed for analysis of the New York City energy system. The analysis specifically aims to consider the built environment and its' impacts on greenhouse gas (GHG) emissions. Several contributions to the urban energy systems literature were made. First, estimates of annual energy intensities of the New York building stock were derived using a statistical analysis that leveraged energy consumption and tax assessor data collected by the Office of the Mayor. These estimates provided the basis for an assessment of the spatial distribution of building energy consumption. The energy consumption estimates were then leveraged to estimate the potential for combined heat and power (CHP) systems in New York City at both the building and microgrid scales. In aggregate, given the 2009 non-baseload GHG emissions factors for electricity production, these systems could reduce citywide GHG emissions by 10%. The operational characteristics of CHP systems were explored further considering different prime movers, climates, and GHG emissions factors. A combination of mixed integer linear programing and controlled random search algorithms were the methods used to determine the optimal capacity and operating strategies for the CHP systems under the various scenarios. Lastly a multi-regional unit commitment model of electricity and GHG emissions production for New York State was developed using data collected from several publicly available sources. The model was used to estimate average and marginal GHG emissions factors for New York State and New York City. The analysis found that marginal GHG emissions factors could reduce by 30% to 370 g CO2e/kWh in the next 10 years.

Italian guidelines for energy performance of cultural heritage and historical buildings: the case study of the Sassi of Matera.

NASA Astrophysics Data System (ADS)

Negro, Elisabetta; Cardinale, Tiziana; Cardinale, Nicola

2016-04-01

The Sassi of Matera are a unique example in the world of rock settlement, developed from natural caves carved into the rock and then molded into increasingly complex structures inside two large natural amphitheatres: the Sasso Caveoso and the Sasso Barisano. Thanks also to this aspects Matera is an UNESCO world heritage site and was elected European Capital of Culture in 2019. Our research focuses on the compatibility of the energy efficiency measures applied in of Sassi buildings with the recent MiBACT (Italian Ministry of Cultural Heritage) guidelines on "Energy efficiency improvements in the cultural heritage" and AiCARR (Italian Association of Air Conditioning) guidelines on "Energy efficiency of historical building". One of the essential measures highlighted by Mibact guidelines is ensure the Indoor Environmental Quality improvement of the historical architecture in order to preserve their identity and cultural heritage. These paper aims to analyze energy and environmental performance of different buildings typology and monuments present in the Sassi site. The energy performance and microclimate measures conducted on different type of building by non-destructive measurements and laboratory tests in situ are useful to verify and quantify the thermal characteristics of the envelopes of the Mediterranean tradition and also to demonstrate their capacity to ensure internal comfort conditions. The calcarenite walls of vernacular building of Sassi show the excellent energy behavior of these constructions. But these material often present high moisture content which negatively influence the room microclimate in particular in presence of mural frescos and rocky churches. However these structures, once restored and in a condition of normal use, give indoor comfort within the limits of thermo-hygrometrics standards established by indices as the predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD). Another interesting consideration stated from our researches is that these buildings are able to reduce the temperature oscillations of the external environment as a result of their high thermal mass. These traditional settlements are typical of the Mediterranean area that has summers with high temperature and daily thermal oscillations. So we can conclude that these buildings could be considered as bioclimatic. Regarding the monuments, as the Matera Cathedral, the evaluation of the indoor microclimate during and after the restoration works shows excellent results and ensures the optimal preservation of artistic heritage from the thermo hygrometric point of view. The plant solution adopted (installation of floor heating system) is in line with the Italian guidelines because this type of system at low temperature allows high energy savings as it enables the use of combustion systems with high-efficiency (condensing boilers) and/or renewable energy installations (heat pumps, solar thermal collectors). A complete knowledge of historical heritage and energy performance of Sassi building is a strategy indicated by Italian guidelines in order to preserve the identity of their inhabitants. So it is necessary to conduct a complete mapping of the entire heritage of this city and develop specific guidelines which combine technical and economic feasibility, appropriate landscaping and architectural integration and environmental sustainability within a proper building lifecycle.

Multi-resonant electromagnetic shunt in base isolation for vibration damping and energy harvesting

NASA Astrophysics Data System (ADS)

Pei, Yalu; Liu, Yilun; Zuo, Lei

2018-06-01

This paper investigates multi-resonant electromagnetic shunts applied to base isolation for dual-function vibration damping and energy harvesting. Two multi-mode shunt circuit configurations, namely parallel and series, are proposed and optimized based on the H2 criteria. The root-mean-square (RMS) value of the relative displacement between the base and the primary structure is minimized. Practically, this will improve the safety of base-isolated buildings subjected the broad bandwidth ground acceleration. Case studies of a base-isolated building are conducted in both the frequency and time domains to investigate the effectiveness of multi-resonant electromagnetic shunts under recorded earthquake signals. It shows that both multi-mode shunt circuits outperform traditional single mode shunt circuits by suppressing the first and the second vibration modes simultaneously. Moreover, for the same stiffness ratio, the parallel shunt circuit is more effective at harvesting energy and suppressing vibration, and can more robustly handle parameter mistuning than the series shunt circuit. Furthermore, this paper discusses experimental validation of the effectiveness of multi-resonant electromagnetic shunts for vibration damping and energy harvesting on a scaled-down base isolation system.

Dynamic Histogram Analysis To Determine Free Energies and Rates from Biased Simulations.

PubMed

Stelzl, Lukas S; Kells, Adam; Rosta, Edina; Hummer, Gerhard

2017-12-12

We present an algorithm to calculate free energies and rates from molecular simulations on biased potential energy surfaces. As input, it uses the accumulated times spent in each state or bin of a histogram and counts of transitions between them. Optimal unbiased equilibrium free energies for each of the states/bins are then obtained by maximizing the likelihood of a master equation (i.e., first-order kinetic rate model). The resulting free energies also determine the optimal rate coefficients for transitions between the states or bins on the biased potentials. Unbiased rates can be estimated, e.g., by imposing a linear free energy condition in the likelihood maximization. The resulting "dynamic histogram analysis method extended to detailed balance" (DHAMed) builds on the DHAM method. It is also closely related to the transition-based reweighting analysis method (TRAM) and the discrete TRAM (dTRAM). However, in the continuous-time formulation of DHAMed, the detailed balance constraints are more easily accounted for, resulting in compact expressions amenable to efficient numerical treatment. DHAMed produces accurate free energies in cases where the common weighted-histogram analysis method (WHAM) for umbrella sampling fails because of slow dynamics within the windows. Even in the limit of completely uncorrelated data, where WHAM is optimal in the maximum-likelihood sense, DHAMed results are nearly indistinguishable. We illustrate DHAMed with applications to ion channel conduction, RNA duplex formation, α-helix folding, and rate calculations from accelerated molecular dynamics. DHAMed can also be used to construct Markov state models from biased or replica-exchange molecular dynamics simulations. By using binless WHAM formulated as a numerical minimization problem, the bias factors for the individual states can be determined efficiently in a preprocessing step and, if needed, optimized globally afterward.

A neural network controller for hydronic heating systems of solar buildings.

PubMed

Argiriou, Athanassios A; Bellas-Velidis, Ioannis; Kummert, Michaël; André, Philippe

2004-04-01

An artificial neural network (ANN)-based controller for hydronic heating plants of buildings is presented. The controller has forecasting capabilities: it includes a meteorological module, forecasting the ambient temperature and solar irradiance, an indoor temperature predictor module, a supply temperature predictor module and an optimizing module for the water supply temperature. All ANN modules are based on the Feed Forward Back Propagation (FFBP) model. The operation of the controller has been tested experimentally, on a real-scale office building during real operating conditions. The operation results were compared to those of a conventional controller. The performance was also assessed via numerical simulation. The detailed thermal simulation tool for solar systems and buildings TRNSYS was used. Both experimental and numerical results showed that the expected percentage of energy savings with respect to a conventional controller is of about 15% under North European weather conditions.

Industrial Energy Efficiency Practices in Indonesia: Lesson Learned from Astra Green Energy (AGen) Award

NASA Astrophysics Data System (ADS)

Telaga, A. S.; Hartanto, I. D.

2017-03-01

Many countries have used award system to promote energy efficiency practices in industry. The award system has been found to have significant impact to increase energy conservation and sustainability adoption in companies. Astra International (AI) as a holding company of more than 200 companies also organised Astra green energy (AGen) award to all affiliated companies (AFFCO) in Astra group. The event has been used to share energy efficiency best practices among AFFCO in Astra group. AFFCOs of Astra International are among the biggest and the leader in their industrial sectors Therefore, analyses from AFFO’s energy efficiency case studies represents current practices in Indonesia industrial sectors. Analyses are divided into industry, building, and renewable energy. The results from analyses found that AFFCOs already aware of energy conservation and have implemented projects to promote energy efficiency. However, the AFFCOs do not optimally use monitoring data for energy reduction.

Energy-Efficient and Comfortable Buildings through Multivariate Integrated Control (ECoMIC)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Birru, Dagnachew; Wen, Yao-Jung; Rubinstein, Francis M.

2013-10-28

This project aims to develop an integrated control solution for enhanced energy efficiency and user comfort in commercial buildings. The developed technology is a zone-based control framework that minimizes energy usage while maintaining occupants’ visual and thermal comfort through control of electric lights, motorized venetian blinds and thermostats. The control framework is designed following a modular, scalable and flexible architecture to facilitate easy integration with exiting building management systems. The control framework contains two key algorithms: 1) the lighting load balancing algorithm and 2) the thermostat control algorithm. The lighting load balancing algorithm adopts a model-based closed-loop control approach tomore » determine the optimal electric light and venetian blind settings. It is formulated into an optimization problem with minimizing lighting-related energy consumptions as the objective and delivering adequate task light and preventing daylight glare as the constraints. The thermostat control algorithm is based on a well-established thermal comfort model and formulated as a root-finding problem to dynamically determine the optimal thermostat setpoint for both energy savings and improved thermal comfort. To address building-wide scalability, a system architecture was developed for the zone-based control technology. Three levels of services are defined in the architecture: external services, facility level services and zone level services. The zone-level service includes the control algorithms described above as well as the corresponding interfaces, profiles, sensors and actuators to realize the zone controller. The facility level services connect to the zones through a backbone network, handle supervisory level information and controls, and thus facilitate building-wide scalability. The external services provide communication capability to entities outside of the building for grid interaction and remote access. Various aspects of the developed control technology were evaluated and verified through both simulations and testbed implementations. Simulations coupling a DOE medium office reference building in EnergyPlus building simulation software and a prototype controller in Matlab were performed. During summer time in a mixed-humid climate zone, the simulations revealed reductions of 27% and 42% in electric lighting load and cooling load, respectively, when compared to an advanced base case with daylight dimming and blinds automatically tilted to block direct sun. Two single-room testbeds were established. The testbed at Philips Lighting business building (Rosemont, IL) was designed for quantifying energy performance of integrated controls. This particular implementation achieved 40% and 79% savings on lighting and HVAC energy, respectively, compared to a relatively simple base case operated on predefined schedules. While the resulting energy savings was very encouraging, it should be noted that there may be several caveats associated with it. 1) The test was run during late spring and early summer, and the savings numbers might not be directly used to extrapolate the annual energy savings. 2) Due to the needs for separate control and metering of the small-scale demonstrator within a large building, the HVAC system, hence the corresponding savings, did not represent a typical energy code-compliant design. 3) The light level in the control case was regulated at a particular setpoint, which was lower than then the full-on light level in the base case, and the savings resulted from tuning down the light level to the setpoint was not attributable to the contribution of the developed technology. The testbed at the Lawrence Berkeley National Laboratory (Berkeley, CA) specifically focused on glare control integration, and has demonstrated the feasibility and capability of the glare detection and prevention technique. While the short one-month test in this testbed provided a functional indication of the developed technology, and it would require at least a full solstice-to-solstice cycle to ruinously quantify the performance, which was not possible within the project timeframe. There are certain limitations inherited from the operational assumptions, which could potentially affect the effectiveness and applicability of the developed control technologies. The system takes a typical ceiling-mounting approach for the photosensor locations, and therefore, the control performance relies on proper commissioning or the built-in intelligence of the photosensor for pertinent task light level estimations. For spaces where daylight penetration diminishes significantly deeper into the zone, certain modification to the control algorithms is required to accommodate multiple lighting control subzones and the corresponding sensors for providing a more uniform light level across the entire zone. Integrated control of visual and thermal comfort requires the lighting control zone and thermal control zone to coincide with each other. In other words, the area illuminated by a lighting circuit needs to be the same area served by the thermostat. Thus, the original zoning will potentially constrain the applicability of this technology in retrofitting projects. This project demonstrated the technical feasibility of a zone-based integrated control technology. From the simulation results and testbed implementations, up to 60% lighting energy savings in daylit areas relative to a “no-controls” case can easily be achieved. A 20% reduction of whole building energy consumption is also attainable. In the aspect of occupant comfort, the testbed demonstrated the ability to maintain specified light level on the workplane while promptly mitigate daylight glare 90% of the time. The control system also managed to maintain the thermal environment at a comfortable level 90% of the time. The aspect of system scalability was guaranteed by the system architecture design, based on which the testbeds were instantiated. Analysis on the aspect of economic benefit has yielded an about 6-year payback time for a medium-sized building, including the installation of all hardware and software, such as motorized blinds and LED luminaires. The payback time can be significantly reduced if part of the hardware is already in place for retrofitting projects. It needs to be noted that since the payback analysis was partly based on the testbed performance results, it is constrained by the caveats associated with the testbed implementations. The main uncertainty lies in the contribution from the space conditioning energy savings as it was non-trivial to realistically configure a room-size HVAC system for directly extrapolating whole-building HVAC energy savings. It is recommended to further evaluate the developed technology at a larger scale, where the lighting and HVAC energy consumption can be realistically measured at the building level, to more rigorously quantify the performance potentials.« less

Optimizing the position of insulating materials in flat roofs exposed to sunshine to gain minimum heat into buildings under periodic heat transfer conditions.

PubMed

Shaik, Saboor; Talanki, Ashok Babu Puttranga Setty

2016-05-01

Building roofs are responsible for the huge heat gain in buildings. In the present work, an analysis of the influence of insulation location inside a flat roof exposed directly to the sun's radiation was performed to reduce heat gain in buildings. The unsteady thermal response parameters of the building roof such as admittance, transmittance, decrement factor, and time lags have been investigated by solving a one-dimensional diffusion equation under convective periodic boundary conditions. Theoretical results of four types of walls were compared with the experimental results available in literature. The results reveal that the roof with insulation placed at the outer side and at the center plane of the roof is the most energy efficient from the lower decrement factor point of view and the roof with insulation placed at the center plane and the inner side of the roof is the best from the highest time lag point of view among the seven studied configurations. The composite roof with expanded polystyrene insulation located at the outer side and at the center plane of the roof is found to be the best roof from the lowest decrement factor (0.130) point of view, and the composite roof with resin-bonded mineral wool insulation located at the center plane and at the inner side of the roof is found to be energy efficient from the highest time lag point (9.33 h) of view among the seven configurations with five different insulation materials studied. The optimum fabric energy storage thicknesses of reinforced cement concrete, expanded polystyrene, foam glass, rock wool, rice husk, resin-bonded mineral wool, and cement plaster were computed. From the results, it is concluded that rock wool has the least optimum fabric energy storage thickness (0.114 m) among the seven studied building roof materials.

A long-term, integrated impact assessment of alternative building energy code scenarios in China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Sha; Eom, Jiyong; Evans, Meredydd

2014-04-01

China is the second largest building energy user in the world, ranking first and third in residential and commercial energy consumption. Beginning in the early 1980s, the Chinese government has developed a variety of building energy codes to improve building energy efficiency and reduce total energy demand. This paper studies the impact of building energy codes on energy use and CO2 emissions by using a detailed building energy model that represents four distinct climate zones each with three building types, nested in a long-term integrated assessment framework GCAM. An advanced building stock module, coupled with the building energy model, ismore » developed to reflect the characteristics of future building stock and its interaction with the development of building energy codes in China. This paper also evaluates the impacts of building codes on building energy demand in the presence of economy-wide carbon policy. We find that building energy codes would reduce Chinese building energy use by 13% - 22% depending on building code scenarios, with a similar effect preserved even under the carbon policy. The impact of building energy codes shows regional and sectoral variation due to regionally differentiated responses of heating and cooling services to shell efficiency improvement.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Yixing; Zhang, Jianshun; Pelken, Michael

Executive Summary The objective of this study was to develop a “Virtual Design Studio (VDS)”: a software platform for integrated, coordinated and optimized design of green building systems with low energy consumption, high indoor environmental quality (IEQ), and high level of sustainability. This VDS is intended to assist collaborating architects, engineers and project management team members throughout from the early phases to the detailed building design stages. It can be used to plan design tasks and workflow, and evaluate the potential impacts of various green building strategies on the building performance by using the state of the art simulation toolsmore » as well as industrial/professional standards and guidelines for green building system design. Engaged in the development of VDS was a multi-disciplinary research team that included architects, engineers, and software developers. Based on the review and analysis of how existing professional practices in building systems design operate, particularly those used in the U.S., Germany and UK, a generic process for performance-based building design, construction and operation was proposed. It distinguishes the whole process into five distinct stages: Assess, Define, Design, Apply, and Monitoring (ADDAM). The current VDS is focused on the first three stages. The VDS considers building design as a multi-dimensional process, involving multiple design teams, design factors, and design stages. The intersection among these three dimensions defines a specific design task in terms of “who”, “what” and “when”. It also considers building design as a multi-objective process that aims to enhance the five aspects of performance for green building systems: site sustainability, materials and resource efficiency, water utilization efficiency, energy efficiency and impacts to the atmospheric environment, and IEQ. The current VDS development has been limited to energy efficiency and IEQ performance, with particular focus on evaluating thermal performance, air quality and lighting environmental quality because of their strong interaction with the energy performance of buildings. The VDS software framework contains four major functions: 1) Design coordination: It enables users to define tasks using the Input-Process-Output flow approach, which specifies the anticipated activities (i.e., the process), required input and output information, and anticipated interactions with other tasks. It also allows task scheduling to define the work flow, and sharing of the design data and information via the internet. 2) Modeling and simulation: It enables users to perform building simulations to predict the energy consumption and IEQ conditions at any of the design stages by using EnergyPlus and a combined heat, air, moisture and pollutant simulation (CHAMPS) model. A method for co-simulation was developed to allow the use of both models at the same time step for the combined energy and indoor air quality analysis. 3) Results visualization: It enables users to display a 3-D geometric design of the building by reading BIM (building information model) file generated by design software such as SketchUp, and the predicted results of heat, air, moisture, pollutant and light distributions in the building. 4) Performance evaluation: It enables the users to compare the performance of a proposed building design against a reference building that is defined for the same type of buildings under the same climate condition, and predicts the percent of improvements over the minimum requirements specified in ASHRAE Standard 55-2010, 62.1-2010 and 90.1-2010. An approach was developed to estimate the potential impact of a design factor on the whole building performance, and hence can assist the user to identify areas that have most pay back for investment. The VDS software was developed by using C++ with the conventional Model, View and Control (MVC) software architecture. The software has been verified by using a simple 3-zone case building. The application of the VDS concepts and framework for building design and performance analysis has been illustrated by using a medium-sized, five story office building that received LEED Platinum Certification from USGBC.« less

Life cycle assessment: Existing building retrofit versus replacement

NASA Astrophysics Data System (ADS)

Darabi, Nura

The embodied energy in building materials constitutes a large part of the total energy required for any building (Thormark 2001, 429). In working to make buildings more energy efficient this needs to be considered. Integrating considerations about life cycle assessment for buildings and materials is one promising way to reduce the amount of energy consumption being used within the building sector and the environmental impacts associated with that energy. A life cycle assessment (LCA) model can be utilized to help evaluate the embodied energy in building materials in comparison to the buildings operational energy. This thesis takes into consideration the potential life cycle reductions in energy and CO2 emissions that can be made through an energy retrofit of an existing building verses demolition and replacement with a new energy efficient building. A 95,000 square foot institutional building built in the 1960`s was used as a case study for a building LCA, along with a calibrated energy model of the existing building created as part of a previous Masters of Building Science thesis. The chosen case study building was compared to 10 possible improvement options of either energy retrofit or replacement of the existing building with a higher energy performing building in order to see the life cycle relationship between embodied energy, operational energy, and C02 emissions. As a result of completing the LCA, it is shown under which scenarios building retrofit saves more energy over the lifespan of the building than replacement with new construction. It was calculated that energy retrofit of the chosen existing institutional building would reduce the amount of energy and C02 emissions associated with that building over its life span.

Design and development of Building energy simulation Software for prefabricated cabin type of industrial building (PCES)

NASA Astrophysics Data System (ADS)

Zhang, Jun; Li, Ri Yi

2018-06-01

Building energy simulation is an important supporting tool for green building design and building energy consumption assessment, At present, Building energy simulation software can't meet the needs of energy consumption analysis and cabinet level micro environment control design of prefabricated building. thermal physical model of prefabricated building is proposed in this paper, based on the physical model, the energy consumption calculation software of prefabricated cabin building(PCES) is developed. we can achieve building parameter setting, energy consumption simulation and building thermal process and energy consumption analysis by PCES.

A multi-criteria model for the comparison of building envelope energy retrofits

NASA Astrophysics Data System (ADS)

Donnarumma, Giuseppe; Fiore, Pierfrancesco

2017-02-01

In light of the current EU guidelines in the energy field, improving building envelope performance cannot be separated from the context of satisfying the environmental sustainability requirements, reducing the costs associated with the life cycle of the building as well as economic and financial feasibility. Therefore, identifying the "optimal" energy retrofit solutions requires the simultaneous assessment of several factors and thus becomes a problem of choice between several possible alternatives. To facilitate the work of the decision-makers, public or private, adequate decision support tools are of great importance. Starting from this need, a model based on the multi-criteria analysis "AHP" technique is proposed, along with the definition of three synthetic indices associated with the three requirements of "Energy Performance", "Sustainability Performance" and "Cost". From the weighted aggregation of the three indices, a global index of preference is obtained that allows to "quantify" the satisfaction level of the i-th alternative from the point of view of a particular group of decision-makers. The model is then applied, by way of example, to the case-study of the energetic redevelopment of a former factory, assuming its functional conversion. Twenty possible alternative interventions on the opaque vertical closures, resulting from the combination of three thermal insulators families (synthetic, natural and mineral) with four energy retrofitting techniques are compared and the results obtained critically discussed by considering the point of view of the three different groups of decision-makers.

User-Preference-Driven Model Predictive Control of Residential Building Loads and Battery Storage for Demand Response: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Xin; Baker, Kyri A.; Christensen, Dane T.

This paper presents a user-preference-driven home energy management system (HEMS) for demand response (DR) with residential building loads and battery storage. The HEMS is based on a multi-objective model predictive control algorithm, where the objectives include energy cost, thermal comfort, and carbon emission. A multi-criterion decision making method originating from social science is used to quickly determine user preferences based on a brief survey and derive the weights of different objectives used in the optimization process. Besides the residential appliances used in the traditional DR programs, a home battery system is integrated into the HEMS to improve the flexibility andmore » reliability of the DR resources. Simulation studies have been performed on field data from a residential building stock data set. Appliance models and usage patterns were learned from the data to predict the DR resource availability. Results indicate the HEMS was able to provide a significant amount of load reduction with less than 20% prediction error in both heating and cooling cases.« less

User-Preference-Driven Model Predictive Control of Residential Building Loads and Battery Storage for Demand Response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Xin; Baker, Kyri A; Isley, Steven C

This paper presents a user-preference-driven home energy management system (HEMS) for demand response (DR) with residential building loads and battery storage. The HEMS is based on a multi-objective model predictive control algorithm, where the objectives include energy cost, thermal comfort, and carbon emission. A multi-criterion decision making method originating from social science is used to quickly determine user preferences based on a brief survey and derive the weights of different objectives used in the optimization process. Besides the residential appliances used in the traditional DR programs, a home battery system is integrated into the HEMS to improve the flexibility andmore » reliability of the DR resources. Simulation studies have been performed on field data from a residential building stock data set. Appliance models and usage patterns were learned from the data to predict the DR resource availability. Results indicate the HEMS was able to provide a significant amount of load reduction with less than 20% prediction error in both heating and cooling cases.« less

Improving building energy efficiency in India: State-level analysis of building energy efficiency policies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Sha; Tan, Qing; Evans, Meredydd

India is expected to add 40 billion m2 of new buildings till 2050. Buildings are responsible for one third of India’s total energy consumption today and building energy use is expected to continue growing driven by rapid income and population growth. The implementation of the Energy Conservation Building Code (ECBC) is one of the measures to improve building energy efficiency. Using the Global Change Assessment Model, this study assesses growth in the buildings sector and impacts of building energy policies in Gujarat, which would help the state adopt ECBC and expand building energy efficiency programs. Without building energy policies, buildingmore » energy use in Gujarat would grow by 15 times in commercial buildings and 4 times in urban residential buildings between 2010 and 2050. ECBC improves energy efficiency in commercial buildings and could reduce building electricity use in Gujarat by 20% in 2050, compared to the no policy scenario. Having energy codes for both commercial and residential buildings could result in additional 10% savings in electricity use. To achieve these intended savings, it is critical to build capacity and institution for robust code implementation.« less

The Multiple-Minima Problem in Protein Folding

NASA Astrophysics Data System (ADS)

Scheraga, Harold A.

1991-10-01

The conformational energy surface of a polypeptide or protein has many local minima, and conventional energy minimization procedures reach only a local minimum (near the starting point of the optimization algorithm) instead of the global minimum (the multiple-minima problem). Several procedures have been developed to surmount this problem, the most promising of which are: (a) build up procedure, (b) optimization of electrostatics, (c) Monte Carlo-plus-energy minimization, (d) electrostatically-driven Monte Carlo, (e) inclusion of distance restraints, (f) adaptive importance-sampling Monte Carlo, (g) relaxation of dimensionality, (h) pattern-recognition, and (i) diffusion equation method. These procedures have been applied to a variety of polypeptide structural problems, and the results of such computations are presented. These include the computation of the structures of open-chain and cyclic peptides, fibrous proteins and globular proteins. Present efforts are being devoted to scaling up these procedures from small polypeptides to proteins, to try to compute the three-dimensional structure of a protein from its amino sequence.

The impact of translucent fabric shades and control strategies on energy savings and visual quality

NASA Astrophysics Data System (ADS)

Wankanapon, Pimonmart

Translucent fabric shades provide opportunities for building occupants to control sunlight penetration for heat reduction, thermal comfort, and visual quality. Regulating shades affects building energy and can potentially reduce the size of mechanical cooling systems. Shades are not normally included in energy model studies during the design process, even though shades potential impact energy use. This is because the occupants normally leave shades closed a large fraction of the time, but models are generally performed with no shades. Automatic shade control is now available, so it is necessary to understand the impact of shades on visual quality and their energy saving potential in order to optimize their overall performance. There are very limited studies that have address shades and their integrated performance on energy consumption and visual quality. Most of these do not reflected modern shade types and their application. The goals of this study are: First, to determine the impact of shades on total, heating, cooling and lighting energy savings with different design and operation parameters. Second, to study and develop different automatic shade control strategies to promote and optimize energy savings and visual quality. A simulation-based approach using EnergyPlus in a parametric study provide better understanding energy savings under different shade conditions. The parametric runs addressed various building parameters such as geometry, orientation, site climate, glazing/shade properties, and shade control strategies with integrated lighting control. The impact of shades was determined for total building and space heating, cooling and lighting energy savings. The effect of shades on visual quality was studied using EnergyPlus, AGI32 and DAYSIM for several indices such as daylight glare index (DGI), work plane illuminance, luminance ratios and view. Different shade control strategies and integrated lighting control were considered with two translucent fabric shade colors. The results clearly show the benefit of automatic shade control strategies with integrated lighting control over a condition when shades are closed all day. The main contributor to the total energy savings is from lighting energy savings, followed by cooling energy savings. Shades provide greater benefit in a hot climate and in a moderate climate than in a cold climate. Different control strategies provide savings in the range of 7-35% for annual total space energy with higher savings with light colored shades. Control strategies of shades should be selected and optimized based on climate, orientation, window area, and window/shade properties. High performance glazings, when equipped with shades, show lower energy savings when compared to standard glazings. High transmittance/reflectance shades, such as white shades, perform better than dark shades in most of the cases due to higher lighting energy savings obtained with the automatic electric lighting control and the resulting cooling energy savings from rejection of some solar energy and a reduction in the heat from lights. A South orientation showed the least benefit of automatic control of shades when compare to other orientations due to the large fraction of time shades are required to provide visual comfort. Under automatic shade control, energy savings are higher the more often the shades can be raised. The different automatic control strategies present tradeoffs between energy savings and comfort. With regard to visual quality, daylight quality assessments on view, glare, luminance ratios, and UDI can be used to assess shade control strategies. Automatic shade control can increase the number of view hours while controlling sunlight penetration. With automatic shade control, more daylight hours can be provided within the beneficial range of 100-2000 lux compared to shades that are closed all day. For a person facing the window, discomfort glare is likely to increase the more often the shades are raised. Keeping the shades down ensures an acceptable glare condition, but limits energy savings. Luminance ratios are another metric that can be used to assess shade performance. With white shades, the luminance ratios between the task and proximate surfaces are improved. Dark shades help improve the luminance ratios between the task and distant surfaces. When the shades are left open, even with no direct sunlight in the space, task to window luminance ratios will often exceed 1:10.

Offshore wind farm layout optimization

NASA Astrophysics Data System (ADS)

Elkinton, Christopher Neil

Offshore wind energy technology is maturing in Europe and is poised to make a significant contribution to the U.S. energy production portfolio. Building on the knowledge the wind industry has gained to date, this dissertation investigates the influences of different site conditions on offshore wind farm micrositing---the layout of individual turbines within the boundaries of a wind farm. For offshore wind farms, these conditions include, among others, the wind and wave climates, water depths, and soil conditions at the site. An analysis tool has been developed that is capable of estimating the cost of energy (COE) from offshore wind farms. For this analysis, the COE has been divided into several modeled components: major costs (e.g. turbines, electrical interconnection, maintenance, etc.), energy production, and energy losses. By treating these component models as functions of site-dependent parameters, the analysis tool can investigate the influence of these parameters on the COE. Some parameters result in simultaneous increases of both energy and cost. In these cases, the analysis tool was used to determine the value of the parameter that yielded the lowest COE and, thus, the best balance of cost and energy. The models have been validated and generally compare favorably with existing offshore wind farm data. The analysis technique was then paired with optimization algorithms to form a tool with which to design offshore wind farm layouts for which the COE was minimized. Greedy heuristic and genetic optimization algorithms have been tuned and implemented. The use of these two algorithms in series has been shown to produce the best, most consistent solutions. The influences of site conditions on the COE have been studied further by applying the analysis and optimization tools to the initial design of a small offshore wind farm near the town of Hull, Massachusetts. The results of an initial full-site analysis and optimization were used to constrain the boundaries of the farm. A more thorough optimization highlighted the features of the area that would result in a minimized COE. The results showed reasonable layout designs and COE estimates that are consistent with existing offshore wind farms.

Secure Distributed Detection under Energy Constraint in IoT-Oriented Sensor Networks.

PubMed

Zhang, Guomei; Sun, Hao

2016-12-16

We study the secure distributed detection problems under energy constraint for IoT-oriented sensor networks. The conventional channel-aware encryption (CAE) is an efficient physical-layer secure distributed detection scheme in light of its energy efficiency, good scalability and robustness over diverse eavesdropping scenarios. However, in the CAE scheme, it remains an open problem of how to optimize the key thresholds for the estimated channel gain, which are used to determine the sensor's reporting action. Moreover, the CAE scheme does not jointly consider the accuracy of local detection results in determining whether to stay dormant for a sensor. To solve these problems, we first analyze the error probability and derive the optimal thresholds in the CAE scheme under a specified energy constraint. These results build a convenient mathematic framework for our further innovative design. Under this framework, we propose a hybrid secure distributed detection scheme. Our proposal can satisfy the energy constraint by keeping some sensors inactive according to the local detection confidence level, which is characterized by likelihood ratio. In the meanwhile, the security is guaranteed through randomly flipping the local decisions forwarded to the fusion center based on the channel amplitude. We further optimize the key parameters of our hybrid scheme, including two local decision thresholds and one channel comparison threshold. Performance evaluation results demonstrate that our hybrid scheme outperforms the CAE under stringent energy constraints, especially in the high signal-to-noise ratio scenario, while the security is still assured.

Secure Distributed Detection under Energy Constraint in IoT-Oriented Sensor Networks

PubMed Central

Zhang, Guomei; Sun, Hao

2016-01-01

We study the secure distributed detection problems under energy constraint for IoT-oriented sensor networks. The conventional channel-aware encryption (CAE) is an efficient physical-layer secure distributed detection scheme in light of its energy efficiency, good scalability and robustness over diverse eavesdropping scenarios. However, in the CAE scheme, it remains an open problem of how to optimize the key thresholds for the estimated channel gain, which are used to determine the sensor’s reporting action. Moreover, the CAE scheme does not jointly consider the accuracy of local detection results in determining whether to stay dormant for a sensor. To solve these problems, we first analyze the error probability and derive the optimal thresholds in the CAE scheme under a specified energy constraint. These results build a convenient mathematic framework for our further innovative design. Under this framework, we propose a hybrid secure distributed detection scheme. Our proposal can satisfy the energy constraint by keeping some sensors inactive according to the local detection confidence level, which is characterized by likelihood ratio. In the meanwhile, the security is guaranteed through randomly flipping the local decisions forwarded to the fusion center based on the channel amplitude. We further optimize the key parameters of our hybrid scheme, including two local decision thresholds and one channel comparison threshold. Performance evaluation results demonstrate that our hybrid scheme outperforms the CAE under stringent energy constraints, especially in the high signal-to-noise ratio scenario, while the security is still assured. PMID:27999282

Developing a landscape of urban building energy use with improved spatiotemporal representations in a cool-humid climate

DOE PAGES

Li, Wenliang; Zhou, Yuyu; Cetin, Kristen S.; ...

2018-03-24

Urban buildings account for up to 75% of total energy use in the United States (U.S.). Understanding urban building energy use is important for developing feasible options to mitigate energy use and greenhouse gas emissions. In this study, an improved bottom-up building energy use model, named City Building Energy Use Model (CityBEUM), was developed to estimate building energy use for all buildings in Polk County, Iowa. First, 28 commercial and 6 residential building prototypes were designed by combing Assessor's parcel data and building footprint data. Then, the EnergyPlus in the CityBEUM was calibrated for all building prototypes using the U.S.more » Energy Information Administration's survey data, monthly utility meter data, and actual weather data. Finally, spatial and temporal variations of building energy use in the study area were estimated using the CityBEUM. Results indicate that the spatial variation of building energy use in the study area can be captured using the CityBEUM. With the monthly-calibrated model, the temporal pattern of urban building energy use can be well represented. The comparison of building energy use using the Typical Meteorological Year and actual weather data demonstrates the importance of using actual weather data in building energy modeling for an improved temporal representation.« less

Developing a landscape of urban building energy use with improved spatiotemporal representations in a cool-humid climate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Wenliang; Zhou, Yuyu; Cetin, Kristen S.

Urban buildings account for up to 75% of total energy use in the United States (U.S.). Understanding urban building energy use is important for developing feasible options to mitigate energy use and greenhouse gas emissions. In this study, an improved bottom-up building energy use model, named City Building Energy Use Model (CityBEUM), was developed to estimate building energy use for all buildings in Polk County, Iowa. First, 28 commercial and 6 residential building prototypes were designed by combing Assessor's parcel data and building footprint data. Then, the EnergyPlus in the CityBEUM was calibrated for all building prototypes using the U.S.more » Energy Information Administration's survey data, monthly utility meter data, and actual weather data. Finally, spatial and temporal variations of building energy use in the study area were estimated using the CityBEUM. Results indicate that the spatial variation of building energy use in the study area can be captured using the CityBEUM. With the monthly-calibrated model, the temporal pattern of urban building energy use can be well represented. The comparison of building energy use using the Typical Meteorological Year and actual weather data demonstrates the importance of using actual weather data in building energy modeling for an improved temporal representation.« less

Heating, ventilation and air conditioning system optimization: a study of the effect of climate, building design, system selection and control strategy on the energy consumption of a typical office building in London and Athens

NASA Astrophysics Data System (ADS)

Spasis, Georgios

The increasing demand for air conditioning in commercial buildings imposes a serious threat to Europe's CO2 reduction targets. Architects and engineers are therefore in a key position to help reduce the impact of buildings on the environment by taking appropriate decisions concerning the design of the building and the associated heating, ventilation and air conditioning (HVAC) system. The thesis studies the effect of a number of building and HVAC system related design factors on the energy performance of a notional air-conditioned office building employing either a variable air volume (VAV) system with terminal re-heaters, or a four-pipe fan coil unit (FCU) system with fresh air supply from a central plant, using mainly a dynamic simulation tool and the response surface methodology. The evaluation of the energy performance of the HVAC systems is for two types of climate, using typical weather data for London (UK) and Athens (Greece). It has been found that the design variables associated with the solar radiation through the transparent building elements and the internal heat gains should be the main concern of the building designer. On the other hand, the HVAC system engineer should give emphasis to the parameters associated with the plant performance and operation, as well as the temperature control set-points. It has been shown that it is possible to reduce the carbon emissions of the base case scenario by up to 88% depending on the HVAC system and the climate for which it is simulated. The carbon savings, however, are reduced by up to 22% where humidification is provided. This reduction differs depending on the HVAC system and the climatic conditions. The VAV system is more energy efficient than the FCU system, mainly due to the exploitation of the free cooling capacity of the outdoor air. The difference in carbon emissions between the two systems drops when both of them are simulated for the Athens as opposed to the London typical weather conditions. It has been found that it is possible to turn the carbon scales in favour of the FCU system when humidification to a high RH set-point is provided throughout the year, since the adjustment of the RH of the air is particularly energy wasteful for the VAV system.

Country Report on Building Energy Codes in Australia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shui, Bin; Evans, Meredydd; Somasundaram, Sriram

2009-04-02

This report is part of a series of reports on building energy efficiency codes in countries associated with the Asian Pacific Partnership (APP) - Australia, South Korea, Japan, China, India, and the United States of America (U.S.). This reports gives an overview of the development of building energy codes in Australia, including national energy policies related to building energy codes, history of building energy codes, recent national projects and activities to promote building energy codes. The report also provides a review of current building energy codes (such as building envelope, HVAC, and lighting) for commercial and residential buildings in Australia.

Review of Methods for Buildings Energy Performance Modelling

NASA Astrophysics Data System (ADS)

Krstić, Hrvoje; Teni, Mihaela

2017-10-01

Research presented in this paper gives a brief review of methods used for buildings energy performance modelling. This paper gives also a comprehensive review of the advantages and disadvantages of available methods as well as the input parameters used for modelling buildings energy performance. European Directive EPBD obliges the implementation of energy certification procedure which gives an insight on buildings energy performance via exiting energy certificate databases. Some of the methods for buildings energy performance modelling mentioned in this paper are developed by employing data sets of buildings which have already undergone an energy certification procedure. Such database is used in this paper where the majority of buildings in the database have already gone under some form of partial retrofitting - replacement of windows or installation of thermal insulation but still have poor energy performance. The case study presented in this paper utilizes energy certificates database obtained from residential units in Croatia (over 400 buildings) in order to determine the dependence between buildings energy performance and variables from database by using statistical dependencies tests. Building energy performance in database is presented with building energy efficiency rate (from A+ to G) which is based on specific annual energy needs for heating for referential climatic data [kWh/(m2a)]. Independent variables in database are surfaces and volume of the conditioned part of the building, building shape factor, energy used for heating, CO2 emission, building age and year of reconstruction. Research results presented in this paper give an insight in possibilities of methods used for buildings energy performance modelling. Further on it gives an analysis of dependencies between buildings energy performance as a dependent variable and independent variables from the database. Presented results could be used for development of new building energy performance predictive model.

Protein structure modeling and refinement by global optimization in CASP12.

PubMed

Hong, Seung Hwan; Joung, InSuk; Flores-Canales, Jose C; Manavalan, Balachandran; Cheng, Qianyi; Heo, Seungryong; Kim, Jong Yun; Lee, Sun Young; Nam, Mikyung; Joo, Keehyoung; Lee, In-Ho; Lee, Sung Jong; Lee, Jooyoung

2018-03-01

For protein structure modeling in the CASP12 experiment, we have developed a new protocol based on our previous CASP11 approach. The global optimization method of conformational space annealing (CSA) was applied to 3 stages of modeling: multiple sequence-structure alignment, three-dimensional (3D) chain building, and side-chain re-modeling. For better template selection and model selection, we updated our model quality assessment (QA) method with the newly developed SVMQA (support vector machine for quality assessment). For 3D chain building, we updated our energy function by including restraints generated from predicted residue-residue contacts. New energy terms for the predicted secondary structure and predicted solvent accessible surface area were also introduced. For difficult targets, we proposed a new method, LEEab, where the template term played a less significant role than it did in LEE, complemented by increased contributions from other terms such as the predicted contact term. For TBM (template-based modeling) targets, LEE performed better than LEEab, but for FM targets, LEEab was better. For model refinement, we modified our CASP11 molecular dynamics (MD) based protocol by using explicit solvents and tuning down restraint weights. Refinement results from MD simulations that used a new augmented statistical energy term in the force field were quite promising. Finally, when using inaccurate information (such as the predicted contacts), it was important to use the Lorentzian function for which the maximal penalty arising from wrong information is always bounded. © 2017 Wiley Periodicals, Inc.

Transient analysis and energy optimization of solar heating and cooling systems in various configurations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calise, F.; Dentice d'Accadia, M.; Palombo, A.

2010-03-15

In this paper, a transient simulation model of solar-assisted heating and cooling systems (SHC) is presented. A detailed case study is also discussed, in which three different configurations are considered. In all cases, the SHC system is based on the coupling of evacuated solar collectors with a single-stage LiBr-H{sub 2}O absorption chiller, and a gas-fired boiler is also included for auxiliary heating, only during the winter season. In the first configuration, the cooling capacity of the absorption chiller and the solar collector area are designed on the basis of the maximum cooling load, and an electric chiller is used asmore » the auxiliary cooling system. The second layout is similar to the first one, but, in this case, the absorption chiller and the solar collector area are sized in order to balance only a fraction of the maximum cooling load. Finally, in the third configuration, there is no electric chiller, and the auxiliary gas-fired boiler is also used in summer to feed the absorption chiller, in case of scarce solar irradiation. The simulation model was developed using the TRNSYS software, and included the analysis of the dynamic behaviour of the building in which the SHC systems were supposed to be installed. The building was simulated using a single-lumped capacitance model. An economic model was also developed, in order to assess the operating and capital costs of the systems under analysis. Furthermore, a mixed heuristic-deterministic optimization algorithm was implemented, in order to determine the set of the synthesis/design variables that maximize the energy efficiency of each configuration under analysis. The results of the case study were analyzed on monthly and weekly basis, paying special attention to the energy and monetary flows of the standard and optimized configurations. The results are encouraging as for the potential of energy saving. On the contrary, the SHC systems appear still far from the economic profitability: however, this is notoriously true for the great majority of renewable energy systems. (author)« less

An international survey of building energy codes and their implementation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Evans, Meredydd; Roshchanka, Volha; Graham, Peter

Buildings are key to low-carbon development everywhere, and many countries have introduced building energy codes to improve energy efficiency in buildings. Yet, building energy codes can only deliver results when the codes are implemented. For this reason, studies of building energy codes need to consider implementation of building energy codes in a consistent and comprehensive way. This research identifies elements and practices in implementing building energy codes, covering codes in 22 countries that account for 70% of global energy demand from buildings. Access to benefits of building energy codes depends on comprehensive coverage of buildings by type, age, size, andmore » geographic location; an implementation framework that involves a certified agency to inspect construction at critical stages; and independently tested, rated, and labeled building energy materials. Training and supporting tools are another element of successful code implementation, and their role is growing in importance, given the increasing flexibility and complexity of building energy codes. Some countries have also introduced compliance evaluation and compliance checking protocols to improve implementation. This article provides examples of practices that countries have adopted to assist with implementation of building energy codes.« less

Recent advances in plasmonic dye-sensitized solar cells

NASA Astrophysics Data System (ADS)

Rho, Won-Yeop; Song, Da Hyun; Yang, Hwa-Young; Kim, Ho-Sub; Son, Byung Sung; Suh, Jung Sang; Jun, Bong-Hyun

2018-02-01

Dye-sensitized solar cells (DSSCs) are among the best devices in generating electrons from solar light energy due to their high efficiency, low-cost in processing and transparency in building integrated photovoltaics. There are several ways to improve their energy-conversion efficiency, such as increasing light harvesting and electron transport, of which plasmon and 3-dimensional nanostructures are greatly capable. We review recent advances in plasmonic effects which depend on optimizing sizes, shapes, alloy compositions and integration of metal nanoparticles. Different methods to integrate metal nanoparticles into 3-dimensional nanostructures are also discussed. This review presents a guideline for enhancing the energy-conversion efficiency of DSSCs by utilizing metal nanoparticles that are incorporated into 3-dimensional nanostructures.

Systems Level Regulation of Rhythmic Growth Rate and Biomass Accumulation in Grasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kay, Steve A.; Hazen, Samuel; Mullet, John

Critical to the development of renewable energy sources from biofuels is the improvement of biomass from energy feedstocks, such as sorghum and maize. The specific goals of this project include 1) characterize the growth and gene expression patterns under diurnal and circadian conditions, 2) select transcription factors associated with growth and build a cis-regulatory network in yeast, and 3) perturb these transcription factors in planta using transgenic Brachypodium and sorghum, and characterize the phenotypic outcomes as they relate to biomass accumulation. A better understanding of diurnally regulated growth behavior in grasses may lead to species-specific mechanisms highly relevant to futuremore » strategies to optimize energy crop biomass yield.« less

FOCUSing on Innovative Solar Technologies

ScienceCinema

Rohlfing, Eric; Holman, Zak, Angel, Roger

2018-06-22

Many of ARPA-E’s technology programs seek to break down silos and build new technological communities around a specific energy challenge. In this video, ARPA-E’s Deputy Director for Technology Eric Rohlfing, discusses how the Full-Spectrum Optimized Conversion and Utilization of Sunlight (FOCUS) program is bringing together the photovoltaic (PV) and concentrated solar power (CSP) communities to develop hybrid solar energy systems. This video features interviews with innovators from the FOCUS project team made up by Arizona State University and the University of Arizona, and showcases how the FOCUS program is combining.

OppoRTUnities Abound

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deru, Michael

According to the U.S. Energy Information Administration, HVAC accounts for approximately 38 percent of U.S. commercial buildings' primary energy consumption and a slightly higher percentage of their greenhouse-gas emissions. We have seen incredible gains made with lighting, going from incandescent and T12 fluorescent bulbs to high-efficiency LEDS, but there are even greater advances to be made with HVAC. Gains of 20 percent to 30 percent easily can be made by replacing older degraded equipment with new high-efficiency equipment. Even more savings are possible with an integrated engineering approach yielding optimized system designs combined with highly efficient controls.

Control of Vibratory Energy Harvesters in the Presence of Nonlinearities and Power-Flow Constraints

NASA Astrophysics Data System (ADS)

Cassidy, Ian L.

Over the past decade, a significant amount of research activity has been devoted to developing electromechanical systems that can convert ambient mechanical vibrations into usable electric power. Such systems, referred to as vibratory energy harvesters, have a number of useful of applications, ranging in scale from self-powered wireless sensors for structural health monitoring in bridges and buildings to energy harvesting from ocean waves. One of the most challenging aspects of this technology concerns the efficient extraction and transmission of power from transducer to storage. Maximizing the rate of power extraction from vibratory energy harvesters is further complicated by the stochastic nature of the disturbance. The primary purpose of this dissertation is to develop feedback control algorithms which optimize the average power generated from stochastically-excited vibratory energy harvesters. This dissertation will illustrate the performance of various controllers using two vibratory energy harvesting systems: an electromagnetic transducer embedded within a flexible structure, and a piezoelectric bimorph cantilever beam. Compared with piezoelectric systems, large-scale electromagnetic systems have received much less attention in the literature despite their ability to generate power at the watt--kilowatt scale. Motivated by this observation, the first part of this dissertation focuses on developing an experimentally validated predictive model of an actively controlled electromagnetic transducer. Following this experimental analysis, linear-quadratic-Gaussian control theory is used to compute unconstrained state feedback controllers for two ideal vibratory energy harvesting systems. This theory is then augmented to account for competing objectives, nonlinearities in the harvester dynamics, and non-quadratic transmission loss models in the electronics. In many vibratory energy harvesting applications, employing a bi-directional power electronic drive to actively control the harvester is infeasible due to the high levels of parasitic power required to operate the drive. For the case where a single-directional drive is used, a constraint on the directionality of power-flow is imposed on the system, which necessitates the use of nonlinear feedback. As such, a sub-optimal controller for power-flow-constrained vibratory energy harvesters is presented, which is analytically guaranteed to outperform the optimal static admittance controller. Finally, the last section of this dissertation explores a numerical approach to compute optimal discretized control manifolds for systems with power-flow constraints. Unlike the sub-optimal nonlinear controller, the numerical controller satisfies the necessary conditions for optimality by solving the stochastic Hamilton-Jacobi equation.

Droop Control of Solar PV, Grid and Critical Load using Suppressing DC Current Injection Technique without Battery Storage

NASA Astrophysics Data System (ADS)

Dama Mr., Jayachandra; (Mrs. , Lini Mathew, Dr.; Srikanth Mr., G.

2017-08-01

This paper presents design of a sustainable solar Photo voltaic system for an Indian cities based residential/community house, integrated with grid, supporting it as supplementary sources, to meet energy demand of domestic loads. The role of renewable energy sources in Distributed Generation (DG) is increasingly being recognized as a supplement and an alternative to large conventional central power supply. Though centralized economic system that solely depends on cities is hampered due to energy deficiency, the use of solar energy in cities is never been tried widely due to technical inconvenience and high installation cost. To mitigate these problems, this paper proposes an optimized design of grid-tied PV system without storage which is suitable for Indian origin as it requires less installallation cost and supplies residential loads when the grid power is unavailable. The energy requirement is mainly fulfilled from PV energy module for critical load of a city located residential house and supplemented by grid/DG for base and peak load. The system has been developed for maximum daily household demand of 50kWp and can be scaled to any higher value as per requirement of individual/community building ranging from 50kWp to 60kWp as per the requirement. A simplified control system model has been developed to optimize and control flow of power from these sources. The simulation work, using MATLAB Simulink software for proposed energy management, has resulted in an optimal yield leading efficient power flow control of proposed system.

Status on the Development of a Modeling and Simulation Framework for the Economic Assessment of Nuclear Hybrid Energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Epiney, Aaron Simon; Chen, Jun; Rabiti, Cristian

Continued effort to design and build a modeling and simulation framework to assess the economic viability of Nuclear Hybrid Energy Systems (NHES) was undertaken in fiscal year (FY) 2016. The purpose of this report is to document the various tasks associated with the development of such a framework and to provide a status of their progress. Several tasks have been accomplished. First, a synthetic time history generator has been developed in RAVEN, which consists of Fourier series and autoregressive moving average model. The former is used to capture the seasonal trend in historical data, while the latter is to characterizemore » the autocorrelation in residue time series (e.g., measurements with seasonal trends subtracted). As demonstration, both synthetic wind speed and grid demand are generated, showing matching statistics with database. In order to build a design and operations optimizer in RAVEN, a new type of sampler has been developed with highly object-oriented design. In particular, simultaneous perturbation stochastic approximation algorithm is implemented. The optimizer is capable to drive the model to optimize a scalar objective function without constraint in the input space, while the constraints handling is a work in progress and will be implemented to improve the optimization capability. Furthermore, a simplified cash flow model of the performance of an NHES in the electric market has been developed in Python and used as external model in RAVEN to confirm expectations on the analysis capability of RAVEN to provide insight into system economics and to test the capability of RAVEN to identify limit surfaces. Finally, an example calculation is performed that shows the integration and proper data passing in RAVEN of the synthetic time history generator, the cash flow model and the optimizer. It has been shown that the developed Python models external to RAVEN are able to communicate with RAVEN and each other through the newly developed RAVEN capability called “EnsembleModel”.« less

Inverse problem and variation method to optimize cascade heat exchange network in central heating system

NASA Astrophysics Data System (ADS)

Zhang, Yin; Wei, Zhiyuan; Zhang, Yinping; Wang, Xin

2017-12-01

Urban heating in northern China accounts for 40% of total building energy usage. In central heating systems, heat is often transferred from heat source to users by the heat network where several heat exchangers are installed at heat source, substations and terminals respectively. For given overall heating capacity and heat source temperature, increasing the terminal fluid temperature is an effective way to improve the thermal performance of such cascade heat exchange network for energy saving. In this paper, the mathematical optimization model of the cascade heat exchange network with three-stage heat exchangers in series is established. Aim at maximizing the cold fluid temperature for given hot fluid temperature and overall heating capacity, the optimal heat exchange area distribution and the medium fluids' flow rates are determined through inverse problem and variation method. The preliminary results show that the heat exchange areas should be distributed equally for each heat exchanger. It also indicates that in order to improve the thermal performance of the whole system, more heat exchange areas should be allocated to the heat exchanger where flow rate difference between two fluids is relatively small. This work is important for guiding the optimization design of practical cascade heating systems.

Balancing Hydronic Systems in Multifamily Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruch, Russell; Ludwig, Peter; Maurer, Tessa

2014-07-01

In multifamily hydronic systems, temperature imbalance may be caused by undersized piping, improperly adjusted balancing valves, inefficient water temperature and flow levels, and owner/occupant interaction with the boilers, distribution, and controls. The imbalance leads to tenant discomfort, higher energy use intensity, and inefficient building operation. This research, conducted by Building America team Partnership for Advanced Residential Retrofit, explores cost-effective distribution upgrades and balancing measures in multifamily hydronic systems, providing a resource to contractors, auditors, and building owners on best practices to improve tenant comfort and lower operating costs. The team surveyed existing knowledge on cost-effective retrofits for optimizing distribution inmore » typical multifamily hydronic systems, with the aim of identifying common situations and solutions, and then conducted case studies on two Chicago area buildings with known balancing issues in order to quantify the extent of temperature imbalance. At one of these buildings a booster pump was installed on a loop to an underheated wing of the building. This study found that unit temperature in a multifamily hydronic building can vary as much as 61°F, particularly if windows are opened or tenants use intermittent supplemental heating sources like oven ranges. Average temperature spread at the building as a result of this retrofit decreased from 22.1°F to 15.5°F.« less

Integrated platform for optimized solar PV system design and engineering plan set generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adeyemo, Samuel

2015-12-30

The Aurora team has developed software that allows users to quickly generate a three-dimensional model for a building, with a corresponding irradiance map, from any two-dimensional image with associated geo-coordinates. The purpose of this project is to build upon that technology by developing and distributing to solar installers a software platform that automatically retrieves engineering, financial and geographic data for a specific site, and quickly generates an optimal customer proposal and corresponding engineering plans for that site. At the end of the project, Aurora’s optimization platform would have been used to make at least one thousand proposals from at leastmore » ten unique solar installation companies, two of whom would sign economically viable contracts to use the software. Furthermore, Aurora’s algorithms would be tested to show that in at least seventy percent of cases, Aurora automatically generated a design equivalent to or better than what a human could have done manually. A ‘better’ design is one that generates more energy for the same cost, or that generates a higher return on investment, while complying with all site-specific aesthetic, electrical and spatial requirements.« less

Advanced Energy Design Guide K-12: Next Generation of School Design and Operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Torcellini, Paul A; Pless, Shanti

Driven by energy efficiency advances and renewable energy cost reductions, zero energy buildings are popping up all around the country. Although zero energy represents a bold paradigm shift - from buildings that consume energy to buildings that produce enough energy to meet their energy needs on an annual basis - it isn't a sudden shift. Zero energy buildings are the result of steady, incremental progress by researchers and building professionals working together to improve building energy performance. ASHRAE is taking the lead by publishing - in partnership with the American Institute of Architects (AIA), the Illuminating Engineering Society (IES), themore » U.S. Green Building Council (USGBC), and the U.S. Department of Energy (DOE) - a new series of advanced energy design guides (AEDGs) focused on zero energy buildings. The recently completed Advanced Energy Design Guide for K-12 School Buildings: Achieving Zero Energy (K-12 ZE AEDG) is the first in this series.« less

Complex analysis of energy efficiency in operated high-rise residential building: Case study

NASA Astrophysics Data System (ADS)

Korniyenko, Sergey

2018-03-01

Energy conservation and human thermal comfort enhancement in buildings is a topical issue of modern architecture and construction. The innovative solution of this problem makes it possible to enhance building ecological and maintenance safety, to reduce hydrocarbon fuel consumption, and to improve life standard of people. The requirements to increase of energy efficiency in buildings should be provided at all the stages of building's life cycle that is at the stage of design, construction and maintenance of buildings. The research purpose is complex analysis of energy efficiency in operated high-rise residential building. Many actions for building energy efficiency are realized according to the project; mainly it is the effective building envelope and engineering systems. Based on results of measurements the energy indicators of the building during annual period have been calculated. The main reason of increase in heat losses consists in the raised infiltration of external air in the building through a building envelope owing to the increased air permeability of windows and balcony doors (construction defects). Thermorenovation of the building based on ventilating and infiltration heat losses reduction through a building envelope allows reducing annual energy consumption. Energy efficiency assessment based on the total annual energy consumption of building, including energy indices for heating and a ventilation, hot water supply and electricity supply, in comparison with heating is more complete. The account of various components in building energy balance completely corresponds to modern direction of researches on energy conservation and thermal comfort enhancement in buildings.

Computational Process Modeling for Additive Manufacturing

NASA Technical Reports Server (NTRS)

Bagg, Stacey; Zhang, Wei

2014-01-01

Computational Process and Material Modeling of Powder Bed additive manufacturing of IN 718. Optimize material build parameters with reduced time and cost through modeling. Increase understanding of build properties. Increase reliability of builds. Decrease time to adoption of process for critical hardware. Potential to decrease post-build heat treatments. Conduct single-track and coupon builds at various build parameters. Record build parameter information and QM Meltpool data. Refine Applied Optimization powder bed AM process model using data. Report thermal modeling results. Conduct metallography of build samples. Calibrate STK models using metallography findings. Run STK models using AO thermal profiles and report STK modeling results. Validate modeling with additional build. Photodiode Intensity measurements highly linear with power input. Melt Pool Intensity highly correlated to Melt Pool Size. Melt Pool size and intensity increase with power. Applied Optimization will use data to develop powder bed additive manufacturing process model.

Automated electrochemical assembly of the protected potential TMG-chitotriomycin precursor based on rational optimization of the carbohydrate building block.

PubMed

Nokami, Toshiki; Isoda, Yuta; Sasaki, Norihiko; Takaiso, Aki; Hayase, Shuichi; Itoh, Toshiyuki; Hayashi, Ryutaro; Shimizu, Akihiro; Yoshida, Jun-ichi

2015-03-20

The anomeric arylthio group and the hydroxyl-protecting groups of thioglycosides were optimized to construct carbohydrate building blocks for automated electrochemical solution-phase synthesis of oligoglucosamines having 1,4-β-glycosidic linkages. The optimization study included density functional theory calculations, measurements of the oxidation potentials, and the trial synthesis of the chitotriose trisaccharide. The automated synthesis of the protected potential N,N,N-trimethyl-d-glucosaminylchitotriomycin precursor was accomplished by using the optimized building block.

Influence of light intensity on surface free energy and dentin bond strength of core build-up resins.

PubMed

Shimizu, Y; Tsujimoto, A; Furuichi, T; Suzuki, T; Tsubota, K; Miyazaki, M; Platt, J A

2015-01-01

We examined the influence of light intensity on surface free energy characteristics and dentin bond strength of dual-cure direct core build-up resin systems. Two commercially available dual-cure direct core build-up resin systems, Clearfil DC Core Automix with Clearfil Bond SE One and UniFil Core EM with Self-Etching Bond, were studied. Bovine mandibular incisors were mounted in acrylic resin and the facial dentin surfaces were wet ground on 600-grit silicon carbide paper. Adhesives were applied to dentin surfaces and cured with light intensities of 0 (no irradiation), 200, 400, and 600 mW/cm(2). The surface free energy of the adhesives (five samples per group) was determined by measuring the contact angles of three test liquids placed on the cured adhesives. To determine the strength of the dentin bond, the core build-up resin pastes were condensed into the mold on the adhesive-treated dentin surfaces according to the methods described for the surface free energy measurement. The resin pastes were cured with the same light intensities as those used for the adhesives. Ten specimens per group were stored in water maintained at 37°C for 24 hours, after which they were shear tested at a crosshead speed of 1.0 mm/minute in a universal testing machine. Two-way analysis of variance (ANOVA) and a Tukey-Kramer test were performed, with the significance level set at 0.05. The surface free energies of the adhesive-treated dentin surfaces decreased with an increase in the light intensity of the curing unit. Two-way ANOVA revealed that the type of core build-up system and the light intensity significantly influence the bond strength, although there was no significant interaction between the two factors. The highest bond strengths were achieved when the resin pastes were cured with the strongest light intensity for all the core build-up systems. When polymerized with a light intensity of 200 mW/cm(2) or less, significantly lower bond strengths were observed. CONClUSIONS: The data suggest that the dentin bond strength of core build-up systems are still affected by the light intensity of the curing unit, which is based on the surface free energy of the adhesives. On the basis of the results and limitations of the test conditions used in this study, it appears that a light intensity of >400 mW/cm(2) may be required for achieving the optimal dentin bond strength.

Data-driven modeling, control and tools for cyber-physical energy systems

NASA Astrophysics Data System (ADS)

Behl, Madhur

Energy systems are experiencing a gradual but substantial change in moving away from being non-interactive and manually-controlled systems to utilizing tight integration of both cyber (computation, communications, and control) and physical representations guided by first principles based models, at all scales and levels. Furthermore, peak power reduction programs like demand response (DR) are becoming increasingly important as the volatility on the grid continues to increase due to regulation, integration of renewables and extreme weather conditions. In order to shield themselves from the risk of price volatility, end-user electricity consumers must monitor electricity prices and be flexible in the ways they choose to use electricity. This requires the use of control-oriented predictive models of an energy system's dynamics and energy consumption. Such models are needed for understanding and improving the overall energy efficiency and operating costs. However, learning dynamical models using grey/white box approaches is very cost and time prohibitive since it often requires significant financial investments in retrofitting the system with several sensors and hiring domain experts for building the model. We present the use of data-driven methods for making model capture easy and efficient for cyber-physical energy systems. We develop Model-IQ, a methodology for analysis of uncertainty propagation for building inverse modeling and controls. Given a grey-box model structure and real input data from a temporary set of sensors, Model-IQ evaluates the effect of the uncertainty propagation from sensor data to model accuracy and to closed-loop control performance. We also developed a statistical method to quantify the bias in the sensor measurement and to determine near optimal sensor placement and density for accurate data collection for model training and control. Using a real building test-bed, we show how performing an uncertainty analysis can reveal trends about inverse model accuracy and control performance, which can be used to make informed decisions about sensor requirements and data accuracy. We also present DR-Advisor, a data-driven demand response recommender system for the building's facilities manager which provides suitable control actions to meet the desired load curtailment while maintaining operations and maximizing the economic reward. We develop a model based control with regression trees algorithm (mbCRT), which allows us to perform closed-loop control for DR strategy synthesis for large commercial buildings. Our data-driven control synthesis algorithm outperforms rule-based demand response methods for a large DoE commercial reference building and leads to a significant amount of load curtailment (of 380kW) and over $45,000 in savings which is 37.9% of the summer energy bill for the building. The performance of DR-Advisor is also evaluated for 8 buildings on Penn's campus; where it achieves 92.8% to 98.9% prediction accuracy. We also compare DR-Advisor with other data driven methods and rank 2nd on ASHRAE's benchmarking data-set for energy prediction.

Building Energy Consumption Pattern Analysis of Detached Housing for the Policy Decision Simulator

NASA Astrophysics Data System (ADS)

Lim, Jiyoun; Lee, Seung-Eon

2018-03-01

The Korean government announced its plan to raise the previous reduction goal of greenhouse gas emission from buildings by 26.9% until 2020 on July 2015. Therefore, policies regarding efficiency in the building energy are implemented fast, but the level of building owners and market understanding is low in general, and the government service system which supports decision making for implementing low-energy buildings has not been provided yet. The purpose of this study is to present the design direction for establishing user customized building energy database to perform a role to provide autonomous ecosystem of low-energy buildings. In order to reduce energy consumption in buildings, it is necessary to carry out the energy performance analysis based on the characteristics of target building. By analysing about 20-thousand cases of the amount of housing energy consumption in Korea, this study suggested the real energy consumption pattern by building types. Also, the energy performance of a building could be determined by energy consumption, but previous building energy consumption analysis programs required expert knowledge and experience in program usage, so it was difficult for normal building users to use such programs. Therefore, a measure to provide proper default using the level of data which general users with no expert knowledge regarding building energy could enter easily was suggested in this study.

Country Report on Building Energy Codes in Canada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shui, Bin; Evans, Meredydd

2009-04-06

This report is part of a series of reports on building energy efficiency codes in countries associated with the Asian Pacific Partnership (APP) - Australia, South Korea, Japan, China, India, and the United States of America . This reports gives an overview of the development of building energy codes in Canada, including national energy policies related to building energy codes, history of building energy codes, recent national projects and activities to promote building energy codes. The report also provides a review of current building energy codes (such as building envelope, HVAC, lighting, and water heating) for commercial and residential buildingsmore » in Canada.« less

Data and Analytics to Inform Energy Retrofit of High Performance Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Tianzhen; Yang, Le; Hill, David

Buildings consume more than one-third of the world?s primary energy. Reducing energy use in buildings with energy efficient technologies is feasible and also driven by energy policies such as energy benchmarking, disclosure, rating, and labeling in both the developed and developing countries. Current energy retrofits focus on the existing building stocks, especially older buildings, but the growing number of new high performance buildings built around the world raises a question that how these buildings perform and whether there are retrofit opportunities to further reduce their energy use. This is a new and unique problem for the building industry. Traditional energymore » audit or analysis methods are inadequate to look deep into the energy use of the high performance buildings. This study aims to tackle this problem with a new holistic approach powered by building performance data and analytics. First, three types of measured data are introduced, including the time series energy use, building systems operating conditions, and indoor and outdoor environmental parameters. An energy data model based on the ISO Standard 12655 is used to represent the energy use in buildings in a three-level hierarchy. Secondly, a suite of analytics were proposed to analyze energy use and to identify retrofit measures for high performance buildings. The data-driven analytics are based on monitored data at short time intervals, and cover three levels of analysis ? energy profiling, benchmarking and diagnostics. Thirdly, the analytics were applied to a high performance building in California to analyze its energy use and identify retrofit opportunities, including: (1) analyzing patterns of major energy end-use categories at various time scales, (2) benchmarking the whole building total energy use as well as major end-uses against its peers, (3) benchmarking the power usage effectiveness for the data center, which is the largest electricity consumer in this building, and (4) diagnosing HVAC equipment using detailed time-series operating data. Finally, a few energy efficiency measures were identified for retrofit, and their energy savings were estimated to be 20percent of the whole-building electricity consumption. Based on the analyses, the building manager took a few steps to improve the operation of fans, chillers, and data centers, which will lead to actual energy savings. This study demonstrated that there are energy retrofit opportunities for high performance buildings and detailed measured building performance data and analytics can help identify and estimate energy savings and to inform the decision making during the retrofit process. Challenges of data collection and analytics were also discussed to shape best practice of retrofitting high performance buildings.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Southface Energy Institute (Southface) partnered with owners and/or builders with various market constraints and ultimate goals for three projects in different climate zones: Savannah, GA (CZ 2), Clemson, SC (CZ 3), and LaFayette, GA (CZ 4). This report documents the design process, computational energy modeling, construction, envelope performance metrics, long-term monitoring results, and successes and failures of the design and execution of these high performance homes. The three bedroom/two bathroom test home in Savannah Gardens on an elevated slab foundation has a semi-conditioned, encapsulated attic. A neighboring home built to EarthCraft specifications was also monitored as a control for exteriormore » foam insulation and a heat pump water heater (HPWH). For the JMC Patrick Square, a single-story project in Clemson, the small-scale production builder wanted to increase their level of energy efficiency beyond their current green building practices, including bringing ducts into conditioned space. Through a combination of upgrade measures the team met this goal and achieved many Zero Energy Ready Home requirements. LaFayette Housing Authority undertook a development of 30 affordable rental housing units in 15 duplexes in LaFayette, GA. Because they would be long-term owners, their priorities were low utility bills for the residents and durable, maintainable buildings. The team employed BEopt to optimize building envelope and systems choices, including 2x6 advanced framed walls, insulated slab, and heat pump water heater in a utility closet which was ducted to/from an encapsulated attic.« less

The Role of Energy Reservoirs in Distributed Computing: Manufacturing, Implementing, and Optimizing Energy Storage in Energy-Autonomous Sensor Nodes

NASA Astrophysics Data System (ADS)

Cowell, Martin Andrew

The world already hosts more internet connected devices than people, and that ratio is only increasing. These devices seamlessly integrate with peoples lives to collect rich data and give immediate feedback about complex systems from business, health care, transportation, and security. As every aspect of global economies integrate distributed computing into their industrial systems and these systems benefit from rich datasets. Managing the power demands of these distributed computers will be paramount to ensure the continued operation of these networks, and is elegantly addressed by including local energy harvesting and storage on a per-node basis. By replacing non-rechargeable batteries with energy harvesting, wireless sensor nodes will increase their lifetimes by an order of magnitude. This work investigates the coupling of high power energy storage with energy harvesting technologies to power wireless sensor nodes; with sections covering device manufacturing, system integration, and mathematical modeling. First we consider the energy storage mechanism of supercapacitors and batteries, and identify favorable characteristics in both reservoir types. We then discuss experimental methods used to manufacture high power supercapacitors in our labs. We go on to detail the integration of our fabricated devices with collaborating labs to create functional sensor node demonstrations. With the practical knowledge gained through in-lab manufacturing and system integration, we build mathematical models to aid in device and system design. First, we model the mechanism of energy storage in porous graphene supercapacitors to aid in component architecture optimization. We then model the operation of entire sensor nodes for the purpose of optimally sizing the energy harvesting and energy reservoir components. In consideration of deploying these sensor nodes in real-world environments, we model the operation of our energy harvesting and power management systems subject to spatially and temporally varying energy availability in order to understand sensor node reliability. Looking to the future, we see an opportunity for further research to implement machine learning algorithms to control the energy resources of distributed computing networks.

An Assessment of Actual and Potential Building Climate Zone Change and Variability From the Last 30 Years Through 2100 Using NASA's MERRA and CMIP5 Simulations

NASA Technical Reports Server (NTRS)

Stackhouse, Paul W., Jr.; Chandler, William S.; Hoell, James M.; Westberg, David; Zhang, Taiping

2015-01-01

Background: In the US, residential and commercial building infrastructure combined consumes about 40% of total energy usage and emits about 39% of total CO2 emission (DOE/EIA "Annual Energy Outlook 2013"). Building codes, as used by local and state enforcement entities are typically tied to the dominant climate within an enforcement jurisdiction classified according to various climate zones. These climate zones are based upon a 30-year average of local surface observations and are developed by DOE and ASHRAE. Establishing the current variability and potential changes to future building climate zones is very important for increasing the energy efficiency of buildings and reducing energy costs and emissions in the future. Objectives: This paper demonstrates the usefulness of using NASA's Modern Era Retrospective-analysis for Research and Applications (MERRA) atmospheric data assimilation to derive the DOE/ASHRAE building climate zone maps and then using MERRA to define the last 30 years of variability in climate zones for the Continental US. An atmospheric assimilation is a global atmospheric model optimized to satellite, atmospheric and surface in situ measurements. Using MERRA as a baseline, we then evaluate the latest Climate Model Inter-comparison Project (CMIP) climate model Version 5 runs to assess potential variability in future climate zones under various assumptions. Methods: We derive DOE/ASHRAE building climate zones using surface and temperature data products from MERRA. We assess these zones using the uncertainties derived by comparison to surface measurements. Using statistical tests, we evaluate variability of the climate zones in time and assess areas in the continental US for statistically significant trends by region. CMIP 5 produced a data base of over two dozen detailed climate model runs under various greenhouse gas forcing assumptions. We evaluate the variation in building climate zones for 3 different decades using an ensemble and quartile statistics to provide an assessment of potential building climate zone changes relative to the uncertainties demonstrated using MERRA. Findings and Conclusions: These results show that there is a statistically significant increase in the area covered by warmer climate zones and a tendency for a reduction of area in colder climate zones in some limited regions. The CMIP analysis shows that models vary from relatively little building climate zone change for the least sensitive and conservation assumptions to a warming of at most 3 zones for certain areas, particularly the north central US by the end of the 21st century.

10 CFR 434.505 - Reference building method.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 3 2013-01-01 2013-01-01 false Reference building method. 434.505 Section 434.505 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.505 Reference building method. 505...

10 CFR 434.505 - Reference building method.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 3 2014-01-01 2014-01-01 false Reference building method. 434.505 Section 434.505 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.505 Reference building method. 505.1...

10 CFR 434.505 - Reference building method.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 3 2012-01-01 2012-01-01 false Reference building method. 434.505 Section 434.505 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.505 Reference building method. 505...

10 CFR 434.505 - Reference building method.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 3 2011-01-01 2011-01-01 false Reference building method. 434.505 Section 434.505 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.505 Reference building method. 505...

10 CFR 434.505 - Reference building method.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Reference building method. 434.505 Section 434.505 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.505 Reference building method. 505...

Scalable Deployment of Advanced Building Energy Management Systems

DTIC Science & Technology

2013-06-01

Building Automation and Control Network BDAS Building Data Acquisition System BEM building energy model BIM building information modeling BMS...A prototype toolkit to seamlessly and automatically transfer a Building Information Model ( BIM ) to a Building Energy Model (BEM) has been...circumvent the need to manually construct and maintain a detailed building energy simulation model . This detailed

Evaluation des apports solaires a l'echelle d'un quartier urbain en periode de chauffe selon sa typologie, son orientation et sa latitude dans un contexte de densification de la ville

NASA Astrophysics Data System (ADS)

Chenard, Laurent

Mass urbanization is a major issue for town administrators. Population increase will have an impact on the quality of the environment for citizens. Government will have to take decisions to limit those effects. Green energies are part of the solution to reach fixed goals by the public administration for sustainable development. Passive solar energy is studied in this work in an urban canopy located in five different towns: San Francisco, Montreal, Bordeaux, Lyon and Stockholm. Passive solar energy is calculated in the heating season. Direct and diffuse solar radiation is considered by using the Perez model. Radiosity is not taken into account. Heating demand is calculated by the heating degree day method. Seven urban forms have been created to determine the amount of solar energy entering in every window of the urban canopy while taking into account urban context and forms. Optimal orientation of the canopy shows an increase of 5% of the passive solar radiation from original orientation, 180 degrees rotation from first orientation straight south. This value goes lower when stories are added to the urban context. A rotation of 90 degrees from the first orientation shows a decrease of 6 to 15% in solar passive gain. Densification of the urban canopy by adding stories to the buildings results in a loss up to 65% of the solar gain for the first story. It is showed that solar passive energy has a low ratio of 5% for space heating for old buildings, 1960 constructions. Today's buildings have a difference between passive solar energy and heating demand of 10 to 75% depending on the model and location.

High Performance Building Facade Solutions - PIER Final Project Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Eleanor; Selkowitz, Stephen

2009-12-31

Building facades directly influence heating and cooling loads and indirectly influence lighting loads when daylighting is considered, and are therefore a major determinant of annual energy use and peak electric demand. Facades also significantly influence occupant comfort and satisfaction, making the design optimization challenge more complex than many other building systems.This work focused on addressing significant near-term opportunities to reduce energy use in California commercial building stock by a) targeting voluntary, design-based opportunities derived from the use of better design guidelines and tools, and b) developing and deploying more efficient glazings, shading systems, daylighting systems, facade systems and integrated controls.more » This two-year project, supported by the California Energy Commission PIER program and the US Department of Energy, initiated a collaborative effort between The Lawrence Berkeley National Laboratory (LBNL) and major stakeholders in the facades industry to develop, evaluate, and accelerate market deployment of emerging, high-performance, integrated facade solutions. The LBNL Windows Testbed Facility acted as the primary catalyst and mediator on both sides of the building industry supply-user business transaction by a) aiding component suppliers to create and optimize cost effective, integrated systems that work, and b) demonstrating and verifying to the owner, designer, and specifier community that these integrated systems reliably deliver required energy performance. An industry consortium was initiated amongst approximately seventy disparate stakeholders, who unlike the HVAC or lighting industry, has no single representative, multi-disciplinary body or organized means of communicating and collaborating. The consortium provided guidance on the project and more importantly, began to mutually work out and agree on the goals, criteria, and pathways needed to attain the ambitious net zero energy goals defined by California and the US.A collaborative test, monitoring, and reporting protocol was also formulated via the Windows Testbed Facility in collaboration with industry partners, transitioning industry to focus on the importance of expecting measured performance to consistently achieve design performance expectations. The facility enables accurate quantification of energy use, peak demand, and occupant comfort impacts of synergistic facade-lighting-HVAC systems on an apples-to-apples comparative basis and its data can be used to verify results from simulations. Emerging interior and exterior shading technologies were investigated as potential near-term, low-cost solutions with potential broad applicability in both new and retrofit construction. Commercially-available and prototype technologies were developed, tested, and evaluated. Full-scale, monitored field tests were conducted over solstice-to-solstice periods to thoroughly evaluate the technologies, uncover potential risks associated with an unknown, and quantify performance benefits. Exterior shading systems were found to yield net zero energy levels of performance in a sunny climate and significant reductions in summer peak demand. Automated interior shading systems were found to yield significant daylighting and comfort-related benefits.In support of an integrated design process, a PC-based commercial fenestration (COMFEN) software package, based on EnergyPlus, was developed that enables architects and engineers to quickly assess and compare the performance of innovative facade technologies in the early sketch or schematic design phase. This tool is publicly available for free and will continue to improve in terms of features and accuracy. Other work was conducted to develop simulation tools to model the performance of any arbitrary complex fenestration system such as common Venetian blinds, fabric roller shades as well as more exotic innovative facade systems such as optical louver systems.« less

Evaluating an Exterior Insulation and Finish System for Deep Energy Retrofits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dentz, Jordan; Podorson, David

Exterior insulation and finish systems (EIFS) are proprietary synthetic formulations that are applied to the exterior walls of buildings to serve as insulation and exterior cladding. The insulation thickness can vary from less than one inch to a foot or more. In this project the applicability of EIFS for residential deep energy retrofits was investigated through modeling and a case study home. The home was retrofitted using a site-applied four-inch-thick EIFS. Site-specific details were developed as required for the residential retrofit application. Site work and the costs of the EIFS system were documented. The demonstration home was modeled using Buildingmore » Energy Optimization energy and cost analysis software to explore cost effectiveness of various EIFS insulation thicknesses in two climate locations.« less

Dispatch Strategy Development for Grid-tied Household Energy Systems

NASA Astrophysics Data System (ADS)

Cardwell, Joseph

The prevalence of renewable generation will increase in the next several decades and offset conventional generation more and more. Yet this increase is not coming without challenges. Solar, wind, and even some water resources are intermittent and unpredictable, and thereby create scheduling challenges due to their inherent "uncontrolled" nature. To effectively manage these distributed renewable assets, new control algorithms must be developed for applications including energy management, bridge power, and system stability. This can be completed through a centralized control center though efforts are being made to parallel the control architecture with the organization of the renewable assets themselves--namely, distributed controls. Building energy management systems are being employed to control localized energy generation, storage, and use to reduce disruption on the net utility load. One such example is VOLTTRONTM, an agent-based platform for building energy control in real time. In this thesis, algorithms developed in VOLTTRON simulate a home energy management system that consists of a solar PV array, a lithium-ion battery bank, and the grid. Dispatch strategies are implemented to reduce energy charges from overall consumption (/kWh) and demand charges (/kW). Dispatch strategies for implementing storage devices are tuned on a month-to-month basis to provide a meaningful economic advantage under simulated scenarios to explore algorithm sensitivity to changing external factors. VOLTTRON agents provide automated real-time optimization of dispatch strategies to efficiently manage energy supply and demand, lower consumer costs associated with energy usage, and reduce load on the utility grid.

Communication: Analytical optimal pulse shapes obtained with the aid of genetic algorithms: Controlling the photoisomerization yield of retinal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guerrero, R. D., E-mail: rdguerrerom@unal.edu.co; Arango, C. A., E-mail: caarango@icesi.edu.co; Reyes, A., E-mail: areyesv@unal.edu.co

We recently proposed a Quantum Optimal Control (QOC) method constrained to build pulses from analytical pulse shapes [R. D. Guerrero et al., J. Chem. Phys. 143(12), 124108 (2015)]. This approach was applied to control the dissociation channel yields of the diatomic molecule KH, considering three potential energy curves and one degree of freedom. In this work, we utilized this methodology to study the strong field control of the cis-trans photoisomerization of 11-cis retinal. This more complex system was modeled with a Hamiltonian comprising two potential energy surfaces and two degrees of freedom. The resulting optimal pulse, made of 6 linearlymore » chirped pulses, was capable of controlling the population of the trans isomer on the ground electronic surface for nearly 200 fs. The simplicity of the pulse generated with our QOC approach offers two clear advantages: a direct analysis of the sequence of events occurring during the driven dynamics, and its reproducibility in the laboratory with current laser technologies.« less

Optimization and Control of Cyber-Physical Vehicle Systems

PubMed Central

Bradley, Justin M.; Atkins, Ella M.

2015-01-01

A cyber-physical system (CPS) is composed of tightly-integrated computation, communication and physical elements. Medical devices, buildings, mobile devices, robots, transportation and energy systems can benefit from CPS co-design and optimization techniques. Cyber-physical vehicle systems (CPVSs) are rapidly advancing due to progress in real-time computing, control and artificial intelligence. Multidisciplinary or multi-objective design optimization maximizes CPS efficiency, capability and safety, while online regulation enables the vehicle to be responsive to disturbances, modeling errors and uncertainties. CPVS optimization occurs at design-time and at run-time. This paper surveys the run-time cooperative optimization or co-optimization of cyber and physical systems, which have historically been considered separately. A run-time CPVS is also cooperatively regulated or co-regulated when cyber and physical resources are utilized in a manner that is responsive to both cyber and physical system requirements. This paper surveys research that considers both cyber and physical resources in co-optimization and co-regulation schemes with applications to mobile robotic and vehicle systems. Time-varying sampling patterns, sensor scheduling, anytime control, feedback scheduling, task and motion planning and resource sharing are examined. PMID:26378541

Optimization and Control of Cyber-Physical Vehicle Systems.

PubMed

Bradley, Justin M; Atkins, Ella M

2015-09-11

A cyber-physical system (CPS) is composed of tightly-integrated computation, communication and physical elements. Medical devices, buildings, mobile devices, robots, transportation and energy systems can benefit from CPS co-design and optimization techniques. Cyber-physical vehicle systems (CPVSs) are rapidly advancing due to progress in real-time computing, control and artificial intelligence. Multidisciplinary or multi-objective design optimization maximizes CPS efficiency, capability and safety, while online regulation enables the vehicle to be responsive to disturbances, modeling errors and uncertainties. CPVS optimization occurs at design-time and at run-time. This paper surveys the run-time cooperative optimization or co-optimization of cyber and physical systems, which have historically been considered separately. A run-time CPVS is also cooperatively regulated or co-regulated when cyber and physical resources are utilized in a manner that is responsive to both cyber and physical system requirements. This paper surveys research that considers both cyber and physical resources in co-optimization and co-regulation schemes with applications to mobile robotic and vehicle systems. Time-varying sampling patterns, sensor scheduling, anytime control, feedback scheduling, task and motion planning and resource sharing are examined.

[Carbon footprint of buildings in the urban agglomeration of central Liaoning, China].

PubMed

Shi, Yu; Yun, Ying Xia; Liu, Chong; Chu, Ya Qi

2017-06-18

With the development of urbanization in China, buildings consumed lots of material and energy. How to estimate carbon emission of buildings is an important scientific problem. Carbon footprint of the central Liaoning agglomeration was studied with carbon footprint approach, geographic information system (GIS) and high-resolution remote sensing (HRRS) technology. The results showed that the construction carbon footprint coefficient of central Liaoning urban agglomeration was 269.16 kg·m -2 . The approach of interpreting total building area and spatial distribution with HRRS was effective, and the accuracy was 89%. The extraction approach was critical for total carbon footprint and spatial distribution estimation. The building area and total carbon footprint of central Liaoning urban agglomeration in descending order was Shenyang, Anshan, Fushun, Liao-yang, Yingkou, Tieling and Benxi. The annual average increment of footprint from 2011 to 2013 in descending order was Shenyang, Benxi, Fushun, Anshan, Tieling, Yingkou and Liaoyang. The accurate estimation of construction carbon footprint spatial and its distribution was of significance for the planning and optimization of carbon emission reduction.

Optimisation structurelle des systemes energetiques

NASA Astrophysics Data System (ADS)

Saloux, Etienne

The development of renewable energies is growing over the last decade to face environmental issues due to the world fossil fuel consumption increase. These energies are highly involved in houses and commercial buildings and numerous systems have been proposed to meet their energy demand. Therefore, improving both efficiency and use of systems, i.e. improving energy management, appears essential to limit the ecological footprint of humanity on the planet. However, system integration yields a very complex problem to be solved due to the large number of units and theirs technology, size, working conditions and interconnections. This situation highlights the lack of systematic analysis for comparing integrated system performance and for correctly pointing out their potential. As a result, the objective of this thesis is to develop and to present such a method, in other words the structural optimization of energy systems. It will be helpful to choose the optimal equipment by identifying all the possibilities of system arrangements and for comparing their performance. Combinations have then been subjected to environmental (climate), structural (available area) and economical constrains while assessment criteria have considered both energy, economic and ecological aspects. For that reason, as well as energy and economic analyses, the exergy concept has also been applied to the equipment. Nevertheless, the high degree of complexity of integrated systems and the tedious numerical calculations make the resolution by using standard software very difficult. It is clear that the whole optimization project would be considerable and the aim is to develop models and optimization tools. First of all, an exhaustive review of energy equipment including photovoltaic panels, solar collectors, heat pumps and thermal energy storage systems, has been performed. Afterwards, energy and exergy models have been developed and tested for two specific energy scenarios: a) a solar assisted heat pump using ice and warm water storages and b) an ambient air heat pump associated to photovoltaic panels. A superstructure has then been constructed to account for every system combination possibility. The different energy paths have been illustrated while irreversibility along every path is identified. Thus, it allows the system operation to be clearly understood. Besides, an exergy diagram has been developed and permits energy and exergy assessment of system and system arrangements to be not only identified but also quantified and separated depending on their (renewable or non-renewable) source. Finally, dimensions and operation variables have been optimized according to exergy and economic criteria for the aforementioned scenarios; the potential of each energy option has been estimated and yield a better energy management to be reached.

Analysis of the Dependence between Energy Demand Indicators in Buildings Based on Variants for Improving Energy Efficiency in a School Building

NASA Astrophysics Data System (ADS)

Skiba, Marta; Rzeszowska, Natalia

2017-09-01

One of the five far-reaching goals of the European Union is climate change and sustainable energy use. The first step in the implementation of this task is to reduce energy demand in buildings to a minimum by 2021, and in the case of public buildings by 2019. This article analyses the possibility of improving energy efficiency in public buildings, the relationship between particular indicators of the demand for usable energy (UE), final energy (FE) and primary energy (PE) in buildings and the impact of these indicators on the assessment of energy efficiency in public buildings, based on 5 variants of extensive thermal renovation of a school building. The analysis of the abovementioned variants confirms that the thermal renovation of merely the outer envelope of the building is insufficient and requires the use of additional energy sources, for example RES. Moreover, each indicator of energy demand in the building plays a key role in assessing the energy efficiency of the building. For this reason it is important to analyze each of them individually, as well as the dependencies between them.

Building Energy Codes: Policy Overview and Good Practices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cox, Sadie

2016-02-19

Globally, 32% of total final energy consumption is attributed to the building sector. To reduce energy consumption, energy codes set minimum energy efficiency standards for the building sector. With effective implementation, building energy codes can support energy cost savings and complementary benefits associated with electricity reliability, air quality improvement, greenhouse gas emission reduction, increased comfort, and economic and social development. This policy brief seeks to support building code policymakers and implementers in designing effective building code programs.

An optimization-based approach for facility energy management with uncertainties, and, Power portfolio optimization in deregulated electricity markets with risk management

NASA Astrophysics Data System (ADS)

Xu, Jun

Topic 1. An Optimization-Based Approach for Facility Energy Management with Uncertainties. Effective energy management for facilities is becoming increasingly important in view of the rising energy costs, the government mandate on the reduction of energy consumption, and the human comfort requirements. This part of dissertation presents a daily energy management formulation and the corresponding solution methodology for HVAC systems. The problem is to minimize the energy and demand costs through the control of HVAC units while satisfying human comfort, system dynamics, load limit constraints, and other requirements. The problem is difficult in view of the fact that the system is nonlinear, time-varying, building-dependent, and uncertain; and that the direct control of a large number of HVAC components is difficult. In this work, HVAC setpoints are the control variables developed on top of a Direct Digital Control (DDC) system. A method that combines Lagrangian relaxation, neural networks, stochastic dynamic programming, and heuristics is developed to predict the system dynamics and uncontrollable load, and to optimize the setpoints. Numerical testing and prototype implementation results show that our method can effectively reduce total costs, manage uncertainties, and shed the load, is computationally efficient. Furthermore, it is significantly better than existing methods. Topic 2. Power Portfolio Optimization in Deregulated Electricity Markets with Risk Management. In a deregulated electric power system, multiple markets of different time scales exist with various power supply instruments. A load serving entity (LSE) has multiple choices from these instruments to meet its load obligations. In view of the large amount of power involved, the complex market structure, risks in such volatile markets, stringent constraints to be satisfied, and the long time horizon, a power portfolio optimization problem is of critical importance but difficulty for an LSE to serve the load, maximize its profit, and manage risks. In this topic, a mid-term power portfolio optimization problem with risk management is presented. Key instruments are considered, risk terms based on semi-variances of spot market transactions are introduced, and penalties on load obligation violations are added to the objective function to improve algorithm convergence and constraint satisfaction. To overcome the inseparability of the resulting problem, a surrogate optimization framework is developed enabling a decomposition and coordination approach. Numerical testing results show that our method effectively provides decisions for various instruments to maximize profit, manage risks, and is computationally efficient.

STTR Phase I: Low-Cost, High-Accuracy, Whole-Building Carbon Dioxide Monitoring for Demand Control Ventilation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hallstrom, Jason O.; Ni, Zheng Richard

This STTR Phase I project assessed the feasibility of a new CO 2 sensing system optimized for low-cost, high-accuracy, whole-building monitoring for use in demand control ventilation. The focus was on the development of a wireless networking platform and associated firmware to provide signal conditioning and conversion, fault- and disruptiontolerant networking, and multi-hop routing at building scales to avoid wiring costs. Early exploration of a bridge (or “gateway”) to direct digital control services was also explored. Results of the project contributed to an improved understanding of a new electrochemical sensor for monitoring indoor CO 2 concentrations, as well as themore » electronics and networking infrastructure required to deploy those sensors at building scales. New knowledge was acquired concerning the sensor’s accuracy, environmental response, and failure modes, and the acquisition electronics required to achieve accuracy over a wide range of CO 2 concentrations. The project demonstrated that the new sensor offers repeatable correspondence with commercial optical sensors, with supporting electronics that offer gain accuracy within 0.5%, and acquisition accuracy within 1.5% across three orders of magnitude variation in generated current. Considering production, installation, and maintenance costs, the technology presents a foundation for achieving whole-building CO 2 sensing at a price point below $0.066 / sq-ft – meeting economic feasibility criteria established by the Department of Energy. The technology developed under this award addresses obstacles on the critical path to enabling whole-building CO 2 sensing and demand control ventilation in commercial retrofits, small commercial buildings, residential complexes, and other highpotential structures that have been slow to adopt these technologies. It presents an opportunity to significantly reduce energy use throughout the United States.« less

Enhancing pseudocapacitive charge storage in polymer templated mesoporous materials.

PubMed

Rauda, Iris E; Augustyn, Veronica; Dunn, Bruce; Tolbert, Sarah H

2013-05-21

Growing global energy demands coupled with environmental concerns have increased the need for renewable energy sources. For intermittent renewable sources like solar and wind to become available on demand will require the use of energy storage devices. Batteries and supercapacitors, also known as electrochemical capacitors (ECs), represent the most widely used energy storage devices. Supercapacitors are frequently overlooked as an energy storage technology, however, despite the fact that these devices provide greater power, much faster response times, and longer cycle life than batteries. Their limitation is that the energy density of ECs is significantly lower than that of batteries, and this has limited their potential applications. This Account reviews our recent work on improving pseudocapacitive energy storage performance by tailoring the electrode architecture. We report our studies of mesoporous transition metal oxide architectures that store charge through surface or near-surface redox reactions, a phenomenon termed pseudocapacitance. The faradaic nature of pseudocapacitance leads to significant increases in energy density and thus represents an exciting future direction for ECs. We show that both the choice of material and electrode architecture is important for producing the ideal pseudocapacitor device. Here we first briefly review the current state of electrode architectures for pseudocapacitors, from slurry electrodes to carbon/metal oxide composites. We then describe the synthesis of mesoporous films made with amphiphilic diblock copolymer templating agents, specifically those optimized for pseudocapacitive charge storage. These include films synthesized from nanoparticle building blocks and films made from traditional battery materials. In the case of more traditional battery materials, we focus on using flexible architectures to minimize the strain associated with lithium intercalation, that is, the accumulation of lithium ions or atoms between the layers of cathode or anode materials that occurs as batteries charge and discharge. Electrochemical analysis of these mesoporous films allows for a detailed understanding of the origin of charge storage by separating capacitive contributions from traditional diffusion-controlled intercalation processes. We also discuss methods to separate the two contributions to capacitance: double-layer capacitance and pseudocapacitance. Understanding these contributions should allow the selection of materials with an optimized architecture that maximize the contribution from pseudocapacitance. From our studies, we show that nanocrystal-based nanoporous materials offer an architecture optimized for high levels of redox or surface pseudocapacitance. Interestingly, in some cases, materials engineered to minimize the strain associated with lithium insertion can also show intercalation pseudocapacitance, which is a process where insertion processes become so kinetically facile that they appear capacitive. Finally, we conclude with a summary of simple design rules that should result in high-power, high-energy-density electrode architectures. These design rules include assembling small, nanosized building blocks to maximize electrode surface area; maintaining an interconnected, open mesoporosity to facilitate solvent diffusion; seeking flexibility in electrode structure to facilitate volume expansion during lithium insertion; optimizing crystalline domain size and orientation; and creating effective electron transport pathways.

Setting Goals and Achieving Aggressing Energy Savings

DTIC Science & Technology

2010-11-30

Path to a Low Energy Building Typical 90.1 Compliant Building National Renewable Energy Laboratory Innovation for Our...flow 1 2 The Path to a Low Energy Building National Renewable Energy Laboratory Innovation for Our Energy Future 0 0% 100...to a Low Energy Building National Renewable Energy Laboratory Innovation for Our Energy Future 0 0% 100% Source Energy

The Applications of NASA Mission Technologies to the Greening of Human Impact

NASA Technical Reports Server (NTRS)

Sims, Michael H.

2009-01-01

I will give an overview talk about flight software systems, robotics technologies and modeling for energy minimization as applied to vehicles and buildings infrastructures. A dominant issue in both design and operations of robotic spacecraft is the minimization of energy use. In the design and building of spacecraft increased power is acquired only at the cost of additional mass and volumes and ultimately cost. Consequently, interplanetary spacecrafts are designed to have the minimum essential power and those designs often incorporate careful timing of all power use. Operationally, the availability of power is the most influential constraint for the use of planetary surface robots, such as the Mars Exploration Rovers. The amount of driving done, the amount of science accomplished and indeed the survivability of the spacecraft itself is determined by the power available for use. For the Mars Exploration Rovers there are four tools which are used: (1) models of the rover and it s thermal and power use (2) predictive environmental models of power input and thermal environment (3) fine grained manipulation of power use (4) optimization modeling and planning tools. In this talk I will discuss possible applications of this methodology to minimizing power use on Earth, especially in buildings.

NET-ZERO ENERGY BUILDING OPERATOR TRAINING PROGRAM (NZEBOT)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brizendine, Anthony; Byars, Nan; Sleiti, Ahmad

2012-12-31

The primary objective of the Net-Zero Energy Building Operator Training Program (NZEBOT) was to develop certificate level training programs for commercial building owners, managers and operators, principally in the areas of energy / sustainability management. The expected outcome of the project was a multi-faceted mechanism for developing the skill-based competency of building operators, owners, architects/engineers, construction professionals, tenants, brokers and other interested groups in energy efficient building technologies and best practices. The training program draws heavily on DOE supported and developed materials available in the existing literature, as well as existing, modified, and newly developed curricula from the Department ofmore » Engineering Technology & Construction Management (ETCM) at the University of North Carolina at Charlotte (UNC-Charlotte). The project goal is to develop a certificate level training curriculum for commercial energy and sustainability managers and building operators that: 1) Increases the skill-based competency of building professionals in energy efficient building technologies and best practices, and 2) Increases the workforce pool of expertise in energy management and conservation techniques. The curriculum developed in this project can subsequently be used to establish a sustainable energy training program that can contribute to the creation of new “green” job opportunities in North Carolina and throughout the Southeast region, and workforce training that leads to overall reductions in commercial building energy consumption. Three energy training / education programs were developed to achieve the stated goal, namely: 1. Building Energy/Sustainability Management (BESM) Certificate Program for Building Managers and Operators (40 hours); 2. Energy Efficient Building Technologies (EEBT) Certificate Program (16 hours); and 3. Energy Efficent Buildings (EEB) Seminar (4 hours). Training Program 1 incorporates the following topics in the primary five-day Building Energy/Sustainability Management Certificate program in five training modules, namely: 1) Strategic Planning, 2) Sustainability Audits, 3) Information Analysis, 4) Energy Efficiency, and 5) Communication. Training Program 2 addresses the following technical topics in the two-day Building Technologies workshop: 1) Energy Efficient Building Materials, 2) Green Roofing Systems, 3) Energy Efficient Lighting Systems, 4) Alternative Power Systems for Buildings, 5) Innovative Building Systems, and 6) Application of Building Performance Simulation Software. Program 3 is a seminar which provides an overview of elements of programs 1 and 2 in a seminar style presentation designed for the general public to raise overall public awareness of energy and sustainability topics.« less

Perspectives of the KM3NeT project

NASA Astrophysics Data System (ADS)

Margiotta, A.; KM3NeT Collaboration

2016-10-01

KM3NeT is a large distributed research infrastructure that comprises a network of deep-sea neutrino telescopes in the Mediterranean Sea with user ports for Earth and Sea sciences. The main objectives of KM3NeT are the discovery and subsequent observation of high-energy neutrino sources in the Universe (ARCA) and the determination of the mass hierarchy of neutrinos (ORCA). Technically, the network of telescopes will consist of building blocks of 115 vertical detection units anchored at the seabed and connected to shore via a deep sea electro-optical cable. Each detection unit carries 18 optical modules equipped with 31 3; photomultipliers. Two configurations for the building blocks are defined to optimally detect neutrinos in different ranges of energy. The modular technical design of the KM3NeT telescope allows for a progressive implementation and for data taking even with an incomplete detector. The first phase of implementation has started. The next phase foresees the installation of three building blocks: two building blocks, for a total instrumented volume of 1 km3 (ARCA), at the KM3NeT-It site, at a depth of 3500 m, about 100 km offshore Capo Passero, Sicily. The main scientific goals of the ARCA detector is the exploration of the neutrino sky with unprecedented resolution, searching for neutrinos coming from defined sources or sky regions, like the Galactic Plane. It will also look for diffuse high energy neutrino fluxes following the indication provided by the IceCube signal. The third building block, with a more compact distribution of the optical modules, will be deployed at the KM3NeT-Fr site, 40 km offshore Toulon at a depth of 2500 m (ORCA). The main objective of ORCA is studying the neutrino mass-hierarchy problem and exploring the low energy region of the spectrum. The status of the first phase of the KM3NeT implementation is described and a survey of the physics potentiality of the telescope is given in this contribution, with particular emphasis on the high energy studies.

76 FR 63913 - Commercial Building Workforce Job/Task Analyses

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-14

..., Commercial Building Energy Modeler, Commissioning/Retro-Commissioning Authority, Energy/Sustainability..., Commercial Building Energy Modeler, Commissioning/Retro-Commissioning Authority, Energy/Sustainability...-commissioning authority, energy/sustainability manager, facility manager, and/or operating engineer/building...

A Systems Approach to High Performance Buildings: A Computational Systems Engineering R&D Program to Increase DoD Energy Efficiency

DTIC Science & Technology

2012-02-01

for Low Energy Building Ventilation and Space Conditioning Systems...Building Energy Models ................... 162 APPENDIX D: Reduced-Order Modeling and Control Design for Low Energy Building Systems .... 172 D.1...Design for Low Energy Building Ventilation and Space Conditioning Systems This section focuses on the modeling and control of airflow in buildings

An international survey of building energy codes and their implementation

DOE PAGES

Evans, Meredydd; Roshchanka, Volha; Graham, Peter

2017-08-01

Buildings are key to low-carbon development everywhere, and many countries have introduced building energy codes to improve energy efficiency in buildings. Yet, building energy codes can only deliver results when the codes are implemented. For this reason, studies of building energy codes need to consider implementation of building energy codes in a consistent and comprehensive way. This research identifies elements and practices in implementing building energy codes, covering codes in 22 countries that account for 70% of global energy use in buildings. These elements and practices include: comprehensive coverage of buildings by type, age, size, and geographic location; an implementationmore » framework that involves a certified agency to inspect construction at critical stages; and building materials that are independently tested, rated, and labeled. Training and supporting tools are another element of successful code implementation. Some countries have also introduced compliance evaluation studies, which suggested that tightening energy requirements would only be meaningful when also addressing gaps in implementation (Pitt&Sherry, 2014; U.S. DOE, 2016b). Here, this article provides examples of practices that countries have adopted to assist with implementation of building energy codes.« less

An international survey of building energy codes and their implementation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Evans, Meredydd; Roshchanka, Volha; Graham, Peter

Buildings are key to low-carbon development everywhere, and many countries have introduced building energy codes to improve energy efficiency in buildings. Yet, building energy codes can only deliver results when the codes are implemented. For this reason, studies of building energy codes need to consider implementation of building energy codes in a consistent and comprehensive way. This research identifies elements and practices in implementing building energy codes, covering codes in 22 countries that account for 70% of global energy use in buildings. These elements and practices include: comprehensive coverage of buildings by type, age, size, and geographic location; an implementationmore » framework that involves a certified agency to inspect construction at critical stages; and building materials that are independently tested, rated, and labeled. Training and supporting tools are another element of successful code implementation. Some countries have also introduced compliance evaluation studies, which suggested that tightening energy requirements would only be meaningful when also addressing gaps in implementation (Pitt&Sherry, 2014; U.S. DOE, 2016b). Here, this article provides examples of practices that countries have adopted to assist with implementation of building energy codes.« less

Micro Climate Simulation in new Town 'Hashtgerd'

NASA Astrophysics Data System (ADS)

Sodoudi, S.; Langer, I.; Cubasch, U.

2012-04-01

One of the objectives of climatological part of project Young Cities 'Developing Energy-Efficient Urban Fabric in the Tehran-Karaj Region' is to simulate the micro climate (with 1m resolution) in 35ha of new town Hashtgerd, which is located 65 km far from mega city Tehran. The Project aims are developing, implementing and evaluating building and planning schemes and technologies which allow to plan and build sustainable, energy-efficient and climate sensible form mass housing settlements in arid and semi-arid regions ("energy-efficient fabric"). Climate sensitive form also means designing and planning for climate change and its related effects for Hashtgerd New Town. By configuration of buildings and open spaces according to solar radiation, wind and vegetation, climate sensitive urban form can create outdoor thermal comfort. To simulate the climate on small spatial scales, the micro climate model Envi-met has been used to simulate the micro climate in 35 ha. The Eulerian model ENVI-met is a micro-scale climate model which gives information about the influence of architecture and buildings as well as vegetation and green area on the micro climate up to 1 m resolution. Envi-met has been run with information from topography, downscaled climate data with neuro-fuzzy method, meteorological measurements, building height and different vegetation variants (low and high number of trees) Through the optimal Urban Design and Planning for the 35ha area the microclimate results shows, that with vegetation the microclimate in streets will be change: • 2 m temperature is decreased by about 2 K • relative humidity increase by about 10 % • soil temperature is decreased by about 3 K • wind speed is decreased by about 60% The style of buildings allows free movement of air, which is of high importance for fresh air supply. The increase of inbuilt areas in 35 ha reduces the heat island effect through cooling caused by vegetation and increase of air humidity which caused by trees evaporation.

Synthetic building materials for transport buildings and structures

NASA Astrophysics Data System (ADS)

Gerasimova, Vera

2017-10-01

The most effective building materials account for the highest growth not only in construction of residential and public buildings, but also other capital projects including roadways, bridges, drainage, communications and other engineering projects. Advancement in the technology of more efficient and ecologically responsible insulation materials have been a priority for safety, minimal maintenance and longevity of finished construction projects. The practical use of modern building materials such as insulation, sound reduction and low energy consumption are a benefit in cost and application compared to the use of outdated heavier and labor-intensive materials. The most efficient way for maximizing insolation and sound proofing should be done during the design stages of the project according to existing codes and regulations that are required by Western Government. All methods and materials that are used need to be optimized in order to reach a high durability and low operational and maintenance cost exceeding more than 50 years of the life of the building, whether it is for public, industrial or residential use. Western construction techniques and technologies need to be applied and adapted by the Russian Federation to insure the most productive successful methods are being implemented. The issues of efficient insulation materials are outlined in this article.

BLACKCOMB2: Hardware-software co-design for non-volatile memory in exascale systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mudge, Trevor

This work was part of a larger project, Blackcomb2, centered at Oak Ridge National Labs (Jeff Vetter PI) to investigate the opportunities for replacing or supplementing DRAM main memory with nonvolatile memory (NVmemory) in Exascale memory systems. The goal was to reduce the energy consumed by in future supercomputer memory systems and to improve their resiliency. Building on the accomplishments of the original Blackcomb Project, funded in 2010, the goal for Blackcomb2 was to identify, evaluate, and optimize the most promising emerging memory technologies, architecture hardware and software technologies, which are essential to provide the necessary memory capacity, performance, resilience,more » and energy efficiency in Exascale systems. Capacity and energy are the key drivers.« less

CO2 Capture Using Electric Fields: Low-Cost Electrochromic Film on Plastic for Net-Zero Energy Building

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2010-01-01

Broad Funding Opportunity Announcement Project: Two faculty members at Lehigh University created a new technique called supercapacitive swing adsorption (SSA) that uses electrical charges to encourage materials to capture and release CO2. Current CO2 capture methods include expensive processes that involve changes in temperature or pressure. Lehigh University’s approach uses electric fields to improve the ability of inexpensive carbon sorbents to trap CO2. Because this process uses electric fields and not electric current, the overall energy consumption is projected to be much lower than conventional methods. Lehigh University is now optimizing the materials to maximize CO2 capture and minimize themore » energy needed for the process.« less

Building Development Monitoring in Multitemporal Remotely Sensed Image Pairs with Stochastic Birth-Death Dynamics.

PubMed

Benedek, C; Descombes, X; Zerubia, J

2012-01-01

In this paper, we introduce a new probabilistic method which integrates building extraction with change detection in remotely sensed image pairs. A global optimization process attempts to find the optimal configuration of buildings, considering the observed data, prior knowledge, and interactions between the neighboring building parts. We present methodological contributions in three key issues: 1) We implement a novel object-change modeling approach based on Multitemporal Marked Point Processes, which simultaneously exploits low-level change information between the time layers and object-level building description to recognize and separate changed and unaltered buildings. 2) To answer the challenges of data heterogeneity in aerial and satellite image repositories, we construct a flexible hierarchical framework which can create various building appearance models from different elementary feature-based modules. 3) To simultaneously ensure the convergence, optimality, and computation complexity constraints raised by the increased data quantity, we adopt the quick Multiple Birth and Death optimization technique for change detection purposes, and propose a novel nonuniform stochastic object birth process which generates relevant objects with higher probability based on low-level image features.

Commercial Building Energy Asset Score

DOE Office of Scientific and Technical Information (OSTI.GOV)

This software (Asset Scoring Tool) is designed to help building owners and managers to gain insight into the as-built efficiency of their buildings. It is a web tool where users can enter their building information and obtain an asset score report. The asset score report consists of modeled building energy use (by end use and by fuel type), building systems (envelope, lighting, heating, cooling, service hot water) evaluations, and recommended energy efficiency measures. The intended users are building owners and operators who have limited knowledge of building energy efficiency. The scoring tool collects minimum building data (~20 data entries) frommore » users and build a full-scale energy model using the inference functionalities from Facility Energy Decision System (FEDS). The scoring tool runs real-time building energy simulation using EnergyPlus and performs life-cycle cost analysis using FEDS. An API is also under development to allow the third-party applications to exchange data with the web service of the scoring tool.« less

The application, benefits and challenges of retrofitting the existing buildings

NASA Astrophysics Data System (ADS)

Khairi, Muhammad; Jaapar, Aini; Yahya, Zaharah

2017-11-01

Sustainable development has been the main topic of debate for years in some countries such as United Kingdom, United State of America and Malaysia. Depletion of natural resources, global warming, economics uncertainty and health issues are some of the reasons behind sustainable development movements, it is not just a political debate in the parliament but more towards collective works among sectors in order to minimizing the negative impact of development to the environment and other living organism. Retrofit an existing building is one of the solutions to reduce the dependency on constructing new buildings. There are huge numbers of existing building stocks that suitable to be retrofitted such as historical buildings, offices, residential, warehouse, factories, vacant buildings and other historical buildings. Therefore, the aim of this research is to provide information on the application, benefits and challenges of retrofitting an existing building. Two buildings were chosen as case studies following by site visits and observation to the buildings. The data were then compared in a table form. Primary and secondary sources were also used for this research. The application of retrofit should be promoted across the construction and conservation industries since it has significant tangible and intangible benefits. It is one of the most environmentally friendly and efficient solutions to optimize the energy performance and could also helps to extend the life of the existing building or historical buildings while ensuring optimum thermal comfort for the occupants which leads to higher productivity.

Climate Impacts on Extreme Energy Consumption of Different Types of Buildings

PubMed Central

Li, Mingcai; Shi, Jun; Guo, Jun; Cao, Jingfu; Niu, Jide; Xiong, Mingming

2015-01-01

Exploring changes of building energy consumption and its relationships with climate can provide basis for energy-saving and carbon emission reduction. Heating and cooling energy consumption of different types of buildings during 1981-2010 in Tianjin city, was simulated by using TRNSYS software. Daily or hourly extreme energy consumption was determined by percentile methods, and the climate impact on extreme energy consumption was analyzed. The results showed that days of extreme heating consumption showed apparent decrease during the recent 30 years for residential and large venue buildings, whereas days of extreme cooling consumption increased in large venue building. No significant variations were found for the days of extreme energy consumption for commercial building, although a decreasing trend in extreme heating energy consumption. Daily extreme energy consumption for large venue building had no relationship with climate parameters, whereas extreme energy consumption for commercial and residential buildings was related to various climate parameters. Further multiple regression analysis suggested heating energy consumption for commercial building was affected by maximum temperature, dry bulb temperature, solar radiation and minimum temperature, which together can explain 71.5 % of the variation of the daily extreme heating energy consumption. The daily extreme cooling energy consumption for commercial building was only related to the wet bulb temperature (R2= 0.382). The daily extreme heating energy consumption for residential building was affected by 4 climate parameters, but the dry bulb temperature had the main impact. The impacts of climate on hourly extreme heating energy consumption has a 1-3 hour delay in all three types of buildings, but no delay was found in the impacts of climate on hourly extreme cooling energy consumption for the selected buildings. PMID:25923205

Climate impacts on extreme energy consumption of different types of buildings.

PubMed

Li, Mingcai; Shi, Jun; Guo, Jun; Cao, Jingfu; Niu, Jide; Xiong, Mingming

2015-01-01

Exploring changes of building energy consumption and its relationships with climate can provide basis for energy-saving and carbon emission reduction. Heating and cooling energy consumption of different types of buildings during 1981-2010 in Tianjin city, was simulated by using TRNSYS software. Daily or hourly extreme energy consumption was determined by percentile methods, and the climate impact on extreme energy consumption was analyzed. The results showed that days of extreme heating consumption showed apparent decrease during the recent 30 years for residential and large venue buildings, whereas days of extreme cooling consumption increased in large venue building. No significant variations were found for the days of extreme energy consumption for commercial building, although a decreasing trend in extreme heating energy consumption. Daily extreme energy consumption for large venue building had no relationship with climate parameters, whereas extreme energy consumption for commercial and residential buildings was related to various climate parameters. Further multiple regression analysis suggested heating energy consumption for commercial building was affected by maximum temperature, dry bulb temperature, solar radiation and minimum temperature, which together can explain 71.5 % of the variation of the daily extreme heating energy consumption. The daily extreme cooling energy consumption for commercial building was only related to the wet bulb temperature (R2= 0.382). The daily extreme heating energy consumption for residential building was affected by 4 climate parameters, but the dry bulb temperature had the main impact. The impacts of climate on hourly extreme heating energy consumption has a 1-3 hour delay in all three types of buildings, but no delay was found in the impacts of climate on hourly extreme cooling energy consumption for the selected buildings.

Federal New Buildings Handbook for Net Zero Energy, Water, and Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

In 2015, the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) defined zero energy buildings as "an energy-efficient building where, on a source energy basis, the actual annual delivered energy is less than or equal to the on-site renewable exported energy." This document is focused on applying EERE’s definition of zero energy buildings to federal sector new buildings. However, it is not intended to replace, substitute, or modify any statutory or regulatory requirements and mandates.

Geometrical analysis on cap-shaped coils for power optimization of the vibration-based electromagnetic harvesting system

NASA Astrophysics Data System (ADS)

Hasbullah Mohd Isa, Wan; Fikri Muhammad, Khairul; Mohd Khairuddin, Ismail; Ishak, Ismayuzri; Razlan Yusoff, Ahmad

2016-02-01

This paper presents the new form of coils for electromagnetic energy harvesting system based on topology optimization method which look-liked a cap to maximize the power output. It could increase the number of magnetic flux linkage interception of a cylindrical permanent magnet which in this case is of 10mm diameter. Several coils with different geometrical properties have been build and tested on a vibration generator with frequency of 100Hz. The results showed that the coil with lowest number of winding transduced highest power output of 680μW while the highest number of windings generated highest voltage output of 0.16V.

BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service

PubMed Central

Zou, Han; Jiang, Hao; Luo, Yiwen; Zhu, Jianjie; Lu, Xiaoxuan; Xie, Lihua

2016-01-01

The location and contextual status (indoor or outdoor) is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS) for individuals. In addition, optimizations of building management systems (BMS), such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO) detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS) easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption. PMID:26907295

Synthesis of Trigeneration Systems: Sensitivity Analyses and Resilience

PubMed Central

Carvalho, Monica; Lozano, Miguel A.; Ramos, José; Serra, Luis M.

2013-01-01

This paper presents sensitivity and resilience analyses for a trigeneration system designed for a hospital. The following information is utilized to formulate an integer linear programming model: (1) energy service demands of the hospital, (2) technical and economical characteristics of the potential technologies for installation, (3) prices of the available utilities interchanged, and (4) financial parameters of the project. The solution of the model, minimizing the annual total cost, provides the optimal configuration of the system (technologies installed and number of pieces of equipment) and the optimal operation mode (operational load of equipment, interchange of utilities with the environment, convenience of wasting cogenerated heat, etc.) at each temporal interval defining the demand. The broad range of technical, economic, and institutional uncertainties throughout the life cycle of energy supply systems for buildings makes it necessary to delve more deeply into the fundamental properties of resilient systems: feasibility, flexibility and robustness. The resilience of the obtained solution is tested by varying, within reasonable limits, selected parameters: energy demand, amortization and maintenance factor, natural gas price, self-consumption of electricity, and time-of-delivery feed-in tariffs. PMID:24453881

Synthesis of trigeneration systems: sensitivity analyses and resilience.

PubMed

Carvalho, Monica; Lozano, Miguel A; Ramos, José; Serra, Luis M

2013-01-01

This paper presents sensitivity and resilience analyses for a trigeneration system designed for a hospital. The following information is utilized to formulate an integer linear programming model: (1) energy service demands of the hospital, (2) technical and economical characteristics of the potential technologies for installation, (3) prices of the available utilities interchanged, and (4) financial parameters of the project. The solution of the model, minimizing the annual total cost, provides the optimal configuration of the system (technologies installed and number of pieces of equipment) and the optimal operation mode (operational load of equipment, interchange of utilities with the environment, convenience of wasting cogenerated heat, etc.) at each temporal interval defining the demand. The broad range of technical, economic, and institutional uncertainties throughout the life cycle of energy supply systems for buildings makes it necessary to delve more deeply into the fundamental properties of resilient systems: feasibility, flexibility and robustness. The resilience of the obtained solution is tested by varying, within reasonable limits, selected parameters: energy demand, amortization and maintenance factor, natural gas price, self-consumption of electricity, and time-of-delivery feed-in tariffs.

10 CFR 434.503 - Prototype building procedure.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 3 2011-01-01 2011-01-01 false Prototype building procedure. 434.503 Section 434.503 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.503 Prototype...

10 CFR 434.503 - Prototype building procedure.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 3 2014-01-01 2014-01-01 false Prototype building procedure. 434.503 Section 434.503 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.503 Prototype...

10 CFR 434.503 - Prototype building procedure.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 3 2012-01-01 2012-01-01 false Prototype building procedure. 434.503 Section 434.503 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.503 Prototype...

10 CFR 434.503 - Prototype building procedure.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 3 2013-01-01 2013-01-01 false Prototype building procedure. 434.503 Section 434.503 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.503 Prototype...

10 CFR 434.503 - Prototype building procedure.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Prototype building procedure. 434.503 Section 434.503 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.503 Prototype...

Energy 101: Energy Efficient Commercial Buildings

ScienceCinema

None

2018-06-06

Learn how commercial buildings can incorporate whole-building design to save energy and money while enhancing performance and comfort. This video highlights several energy-saving features of the Research Support Facility at the Energy Department's National Renewable Energy Laboratory-a model for high-performance office building design.

Building Energy Monitoring and Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Tianzhen; Feng, Wei; Lu, Alison

This project aimed to develop a standard methodology for building energy data definition, collection, presentation, and analysis; apply the developed methods to a standardized energy monitoring platform, including hardware and software, to collect and analyze building energy use data; and compile offline statistical data and online real-time data in both countries for fully understanding the current status of building energy use. This helps decode the driving forces behind the discrepancy of building energy use between the two countries; identify gaps and deficiencies of current building energy monitoring, data collection, and analysis; and create knowledge and tools to collect and analyzemore » good building energy data to provide valuable and actionable information for key stakeholders.« less

Investigating the optimal passive and active vibration controls of adjacent buildings based on performance indices using genetic algorithms

NASA Astrophysics Data System (ADS)

Hadi, Muhammad N. S.; Uz, Mehmet E.

2015-02-01

This study proposes the optimal passive and active damper parameters for achieving the best results in seismic response mitigation of coupled buildings connected to each other by dampers. The optimization to minimize the H2 and H∞ norms in the performance indices is carried out by genetic algorithms (GAs). The final passive and active damper parameters are checked for adjacent buildings connected to each other under El Centro NS 1940 and Kobe NS 1995 excitations. Using real coded GA in H∞ norm, the optimal controller gain is obtained by different combinations of the measurement as the feedback for designing the control force between the buildings. The proposed method is more effective than other metaheuristic methods and more feasible, although the control force increased. The results in the active control system show that the response of adjacent buildings is reduced in an efficient manner.

Conceptual optimization using genetic algorithms for tube in tube structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pârv, Bianca Roxana; Hulea, Radu; Mojolic, Cristian

2015-03-10

The purpose of this article is to optimize the tube in tube structural systems for tall buildings under the horizontal wind loads. It is well-known that the horizontal wind loads is the main criteria when choosing the structural system, the types and the dimensions of structural elements in the majority of tall buildings. Thus, the structural response of tall buildings under the horizontal wind loads will be analyzed for 40 story buildings and a total height of 120 meters; the horizontal dimensions will be 30m × 30m for the first two optimization problems and 15m × 15m for the third.more » The optimization problems will have the following as objective function the cross section area, as restrictions the displacement of the building< the admissible displacement (H/500), and as variables the cross section dimensions of the structural elements.« less

Optimal Management and Design of Energy Systems under Atmospheric Uncertainty

NASA Astrophysics Data System (ADS)

Anitescu, M.; Constantinescu, E. M.; Zavala, V.

2010-12-01

The generation and distpatch of electricity while maintaining high reliability levels are two of the most daunting engineering problems of the modern era. This was demonstrated by the Northeast blackout of August 2003, which resulted in the loss of 6.2 gigawatts that served more than 50 million people and which resulted in economic losses on the order of $10 billion. In addition, there exist strong socioeconomic pressures to improve the efficiency of the grid. The most prominent solution to this problem is a substantial increase in the use of renewable energy such as wind and solar. In turn, its uncertain availability—which is due to the intrinsic weather variability—will increase the likelihood of disruptions. In this endeavors of current and next-generation power systems, forecasting atmospheric conditions with uncertainty can and will play a central role, at both the demand and the generation ends. User demands are strongly correlated to physical conditions such as temperature, humidity, and solar radiation. The reason is that the ambient temperature and solar radiation dictate the amount of air conditioning and lighting needed in residential and commercial buildings. But these potential benefits would come at the expense of increased variability in the dynamics of both production and demand, which would become even more dependent on weather state and its uncertainty. One of the important challenges for energy in our time is how to harness these benefits while “keeping the lights on”—ensuring that the demand is satisfied at all times and that no blackout occurs while all energy sources are optimally used. If we are to meet this challenge, accounting for uncertainty in the atmospheric conditions is essential, since this will allow minimizing the effects of false positives: committing too little baseline power in anticipation of demand that is underestimated or renewable energy levels that fail to materialize. In this work we describe a framework for the optimal management and design of energy systems, such as the power grid or building systems, under atmospheric conditions uncertainty. The framework is defined in terms of a mathematical paradigm called stochastic programming: minimization of the expected value of the decision-makers objective function subject to physical and operational constraints, such as low blackout porbability, that are enforced on each scenario. We report results on testing the framework on the optimal management of power grid systems under high wind penetration scenarios, a problem whose time horizon is in the order of days. We discuss the computational effort of scenario generation which involves running WRF at high spatio-temporal resolution dictated by the operational constraints as well as solving the optimal dispatch problem. We demonstrate that accounting for uncertainty in atmospheric conditions results in blackout prevention, whereas decisions using only mean forecast does not. We discuss issues in using the framework for planning problems, whose time horizon is of several decades and what requirements this problem would entail from climate simulation systems.

10 CFR 434.506 - Use of the reference building to determine the energy cost budget.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Use of the reference building to determine the energy cost budget. 434.506 Section 434.506 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance...

10 CFR 434.504 - Use of the prototype building to determine the energy cost budget.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Use of the prototype building to determine the energy cost budget. 434.504 Section 434.504 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance...

Executive Order 13514: Federal Leadership in Environmental, Energy, and Economic Performance; Comprehensive Federal Fleet Management Handbook (Book)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daley, R.; Ahdieh, N.; Bentley, J.

2014-01-01

A comprehensive Federal Fleet Management Handbook that builds upon the "Guidance for Federal Agencies on E.O. 13514 Section 12-Federal Fleet Management" and provides information to help fleet managers select optimal greenhouse gas and petroleum reduction strategies for each location, meeting or exceeding related fleet requirements, acquiring vehicles to support these strategies while minimizing fleet size and vehicle miles traveled, and refining strategies based on agency performance.

Acceleration of the matrix multiplication of Radiance three phase daylighting simulations with parallel computing on heterogeneous hardware of personal computer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zuo, Wangda; McNeil, Andrew; Wetter, Michael

2013-05-23

Building designers are increasingly relying on complex fenestration systems to reduce energy consumed for lighting and HVAC in low energy buildings. Radiance, a lighting simulation program, has been used to conduct daylighting simulations for complex fenestration systems. Depending on the configurations, the simulation can take hours or even days using a personal computer. This paper describes how to accelerate the matrix multiplication portion of a Radiance three-phase daylight simulation by conducting parallel computing on heterogeneous hardware of a personal computer. The algorithm was optimized and the computational part was implemented in parallel using OpenCL. The speed of new approach wasmore » evaluated using various daylighting simulation cases on a multicore central processing unit and a graphics processing unit. Based on the measurements and analysis of the time usage for the Radiance daylighting simulation, further speedups can be achieved by using fast I/O devices and storing the data in a binary format.« less

Building Energy Asset Score for Building Owners

DOE Office of Scientific and Technical Information (OSTI.GOV)

Building Technologies Office

2015-01-01

The Building Energy Asset Score is a national standardized tool for evaluating the physical and structural energy efficiency of commercial and multifamily residential buildings. The Asset Score generates a simple energy efficiency rating that enables comparison among buildings, and identifies opportunities for users to invest in energy efficiency upgrades. It is web-based and free to use. This fact sheet discusses the value of the score for building owners.

Deep influence of passive low energy consumption multi-storey residential building in cold region

NASA Astrophysics Data System (ADS)

Shuai, Zhang; Lihua, Zhao; Rong, Jin; Dong, Junyan

2018-02-01

The example of passive architecture demonstration building in Jilin Province, China, based on the practical experience of this project, the control index of passive and low energy consumption residential buildings in cold and passive buildings is referenced by reference to the German construction standard and the Chinese residence construction document, “passive ultra-low energy consumption green Building Technology Guide (Trial)”. The requirement of passive low energy residential buildings on the ground heat transfer coefficient limits is determined, and the performance requirements of passive residential buildings are discussed. This paper analyzes the requirement of the passive low energy residential building on the ground heat transfer coefficient limit, and probes into the influence factors of the ground thermal insulation of the passive low energy consumption residential building. The construction method of passive low energy consumption residential building is proposed.

Commercial Building Tenant Energy Usage Aggregation and Privacy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Livingston, Olga V.; Pulsipher, Trenton C.; Anderson, David M.

A growing number of building owners are benchmarking their building energy use. This requires the building owner to acquire monthly whole-building energy usage information, which can be challenging for buildings in which individual tenants have their own utility meters and accounts with the utility. Some utilities and utility regulators have turned to aggregation of customer energy use data (CEUD) as a way to give building owners whole-building energy usage data while protecting customer privacy. Meter profile aggregation adds a layer of protection that decreases the risk of revealing CEUD as the number of meters aggregated increases. The report statistically characterizesmore » the similarity between individual energy usage patterns and whole-building totals at various levels of meter aggregation.« less

Overview of Commercial Buildings, 2003

EIA Publications

2008-01-01

The Energy Information Administration conducts the Commercial Buildings Energy Consumption Survey (CBECS) to collect information on energy-related building characteristics and types and amounts of energy consumed in commercial buildings in the United States.

National Cost-effectiveness of ASHRAE Standard 90.1-2010 Compared to ASHRAE Standard 90.1-2007

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thornton, Brian; Halverson, Mark A.; Myer, Michael

Pacific Northwest National Laboratory (PNNL) completed this project for the U.S. Department of Energy’s (DOE’s) Building Energy Codes Program (BECP). DOE’s BECP supports upgrading building energy codes and standards, and the states’ adoption, implementation, and enforcement of upgraded codes and standards. Building energy codes and standards set minimum requirements for energy-efficient design and construction for new and renovated buildings, and impact energy use and greenhouse gas emissions for the life of buildings. Continuous improvement of building energy efficiency is achieved by periodically upgrading energy codes and standards. Ensuring that changes in the code that may alter costs (for building components,more » initial purchase and installation, replacement, maintenance and energy) are cost-effective encourages their acceptance and implementation. ANSI/ASHRAE/IESNA Standard 90.1 is the energy standard for commercial and multi-family residential buildings over three floors.« less

Cost-effectiveness of ASHRAE Standard 90.1-2010 Compared to ASHRAE Standard 90.1-2007

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thornton, Brian A.; Halverson, Mark A.; Myer, Michael

Pacific Northwest National Laboratory (PNNL) completed this project for the U.S. Department of Energy’s (DOE’s) Building Energy Codes Program (BECP). DOE’s BECP supports upgrading building energy codes and standards, and the states’ adoption, implementation, and enforcement of upgraded codes and standards. Building energy codes and standards set minimum requirements for energy-efficient design and construction for new and renovated buildings, and impact energy use and greenhouse gas emissions for the life of buildings. Continuous improvement of building energy efficiency is achieved by periodically upgrading energy codes and standards. Ensuring that changes in the code that may alter costs (for building components,more » initial purchase and installation, replacement, maintenance and energy) are cost-effective encourages their acceptance and implementation. ANSI/ASHRAE/IESNA Standard 90.1 is the energy standard for commercial and multi-family residential buildings over three floors.« less

Development of a Low-Lift Chiller Controller and Simplified Precooling Control Algorithm - Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gayeski, N.; Armstrong, Peter; Alvira, M.

2011-11-30

KGS Buildings LLC (KGS) and Pacific Northwest National Laboratory (PNNL) have developed a simplified control algorithm and prototype low-lift chiller controller suitable for model-predictive control in a demonstration project of low-lift cooling. Low-lift cooling is a highly efficient cooling strategy conceived to enable low or net-zero energy buildings. A low-lift cooling system consists of a high efficiency low-lift chiller, radiant cooling, thermal storage, and model-predictive control to pre-cool thermal storage overnight on an optimal cooling rate trajectory. We call the properly integrated and controlled combination of these elements a low-lift cooling system (LLCS). This document is the final report formore » that project.« less

Estimation of the Relationship Between Remotely Sensed Anthropogenic Heat Discharge and Building Energy Use

NASA Technical Reports Server (NTRS)

Zhou, Yuyu; Weng, Qihao; Gurney, Kevin R.; Shuai, Yanmin; Hu, Xuefei

2012-01-01

This paper examined the relationship between remotely sensed anthropogenic heat discharge and energy use from residential and commercial buildings across multiple scales in the city of Indianapolis, Indiana, USA. The anthropogenic heat discharge was estimated with a remote sensing-based surface energy balance model, which was parameterized using land cover, land surface temperature, albedo, and meteorological data. The building energy use was estimated using a GIS-based building energy simulation model in conjunction with Department of Energy/Energy Information Administration survey data, the Assessor's parcel data, GIS floor areas data, and remote sensing-derived building height data. The spatial patterns of anthropogenic heat discharge and energy use from residential and commercial buildings were analyzed and compared. Quantitative relationships were evaluated across multiple scales from pixel aggregation to census block. The results indicate that anthropogenic heat discharge is consistent with building energy use in terms of the spatial pattern, and that building energy use accounts for a significant fraction of anthropogenic heat discharge. The research also implies that the relationship between anthropogenic heat discharge and building energy use is scale-dependent. The simultaneous estimation of anthropogenic heat discharge and building energy use via two independent methods improves the understanding of the surface energy balance in an urban landscape. The anthropogenic heat discharge derived from remote sensing and meteorological data may be able to serve as a spatial distribution proxy for spatially-resolved building energy use, and even for fossil-fuel CO2 emissions if additional factors are considered.

The potential of net zero energy buildings (NZEBs) concept at design stage for healthcare buildings towards sustainable development

NASA Astrophysics Data System (ADS)

Hazli Abdellah, Roy; Asrul Nasid Masrom, Md; Chen, Goh Kai; Mohamed, Sulzakimin; Omar, Roshartini

2017-11-01

The focus on net-zero energy buildings (NZEBs) has been widely analysed and discussed particularly when European Union Parliament are progressively moving towards regulation that promotes the improvement of energy efficiency (EE). Additionally, it also to reduce energy consumption through the recast of the EU Directive on Energy Performance of Buildings (EPBD) in which all new buildings to be “nearly Zero-Energy” Buildings by 2020. Broadly, there is a growing trend to explore the feasibility of net zero energy in healthcare sector as the level energy consumption for healthcare sector is found significantly high. Besides that, healthcare buildings energy consumption also exceeds of many other nondomestic building types, and this shortcoming is still undetermined yet especially for developing countries. This paper aims to review the potential of NZEBs in healthcare buildings by considering its concept in design features. Data are gathered through a comprehensive energy management literature review from previous studies. The review is vital to encourage construction players to increase their awareness, practices, and implementation of NZEBs in healthcare buildings. It suggests that NZEBs concept has a potential to be adapted in healthcare buildings through emphasizing of passive approach as well as the utilization of energy efficiency systems and renewable energy systems in buildings. This paper will provide a basis knowledge for construction key players mainly architects to promote NZEBs concept at design stage for healthcare buildings development.

Federal Existing Buildings Handbook for Net Zero Energy, Water, and Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

In 2015, the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) defined zero energy buildings as "an energy-efficient building where, on a source energy basis, the actual annual delivered energy is less than or equal to the on-site renewable exported energy." This handbook is focused on applying the EERE definition of zero energy buildings to existing buildings in the federal sector. However, it is not intended to replace, substitute, or modify any statutory or regulatory requirements and mandates.

Commercial Building Energy Saver, Web App

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Tianzhen; Piette, Mary; Lee, Sang Hoon

The CBES App is a web-based toolkit for use by small businesses and building owners and operators of small and medium size commercial buildings to perform energy benchmarking and retrofit analysis for buildings. The CBES App analyzes the energy performance of user's building for pre-and posto-retrofit, in conjunction with user's input data, to identify recommended retrofit measures, energy savings and economic analysis for the selected measures. The CBES App provides energy benchmarking, including getting an EnergyStar score using EnergyStar API and benchmarking against California peer buildings using the EnergyIQ API. The retrofit analysis includes a preliminary analysis by looking upmore » retrofit measures from a pre-simulated database DEEP, and a detailed analysis creating and running EnergyPlus models to calculate energy savings of retrofit measures. The CBES App builds upon the LBNL CBES API.« less

Derivation of Reliable Geometries in QM Calculations of DNA Structures: Explicit Solvent QM/MM and Restrained Implicit Solvent QM Optimizations of G-Quadruplexes.

PubMed

Gkionis, Konstantinos; Kruse, Holger; Šponer, Jiří

2016-04-12

Modern dispersion-corrected DFT methods have made it possible to perform reliable QM studies on complete nucleic acid (NA) building blocks having hundreds of atoms. Such calculations, although still limited to investigations of potential energy surfaces, enhance the portfolio of computational methods applicable to NAs and offer considerably more accurate intrinsic descriptions of NAs than standard MM. However, in practice such calculations are hampered by the use of implicit solvent environments and truncation of the systems. Conventional QM optimizations are spoiled by spurious intramolecular interactions and severe structural deformations. Here we compare two approaches designed to suppress such artifacts: partially restrained continuum solvent QM and explicit solvent QM/MM optimizations. We report geometry relaxations of a set of diverse double-quartet guanine quadruplex (GQ) DNA stems. Both methods provide neat structures without major artifacts. However, each one also has distinct weaknesses. In restrained optimizations, all errors in the target geometries (i.e., low-resolution X-ray and NMR structures) are transferred to the optimized geometries. In QM/MM, the initial solvent configuration causes some heterogeneity in the geometries. Nevertheless, both approaches represent a decisive step forward compared to conventional optimizations. We refine earlier computations that revealed sizable differences in the relative energies of GQ stems computed with AMBER MM and QM. We also explore the dependence of the QM/MM results on the applied computational protocol.

Optimal deployment of thermal energy storage under diverse economic and climate conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeForest, Nicholas; Mendes, Gonçalo; Stadler, Michael

2014-04-01

This paper presents an investigation of the economic benefit of thermal energy storage (TES) for cooling, across a range of economic and climate conditions. Chilled water TES systems are simulated for a large office building in four distinct locations, Miami in the U.S.; Lisbon, Portugal; Shanghai, China; and Mumbai, India. Optimal system size and operating schedules are determined using the optimization model DER-CAM, such that total cost, including electricity and amortized capital costs are minimized. The economic impacts of each optimized TES system is then compared to systems sized using a simple heuristic method, which bases system size as fractionmore » (50percent and 100percent) of total on-peak summer cooling loads. Results indicate that TES systems of all sizes can be effective in reducing annual electricity costs (5percent-15percent) and peak electricity consumption (13percent-33percent). The investigation also indentifies a number of criteria which drive TES investment, including low capital costs, electricity tariffs with high power demand charges and prolonged cooling seasons. In locations where these drivers clearly exist, the heuristically sized systems capture much of the value of optimally sized systems; between 60percent and 100percent in terms of net present value. However, in instances where these drivers are less pronounced, the heuristic tends to oversize systems, and optimization becomes crucial to ensure economically beneficial deployment of TES, increasing the net present value of heuristically sized systems by as much as 10 times in some instances.« less

DEEP: A Database of Energy Efficiency Performance to Accelerate Energy Retrofitting of Commercial Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoon Lee, Sang; Hong, Tianzhen; Sawaya, Geof

The paper presents a method and process to establish a database of energy efficiency performance (DEEP) to enable quick and accurate assessment of energy retrofit of commercial buildings. DEEP was compiled from results of about 35 million EnergyPlus simulations. DEEP provides energy savings for screening and evaluation of retrofit measures targeting the small and medium-sized office and retail buildings in California. The prototype building models are developed for a comprehensive assessment of building energy performance based on DOE commercial reference buildings and the California DEER prototype buildings. The prototype buildings represent seven building types across six vintages of constructions andmore » 16 California climate zones. DEEP uses these prototypes to evaluate energy performance of about 100 energy conservation measures covering envelope, lighting, heating, ventilation, air-conditioning, plug-loads, and domestic hot water. DEEP consists the energy simulation results for individual retrofit measures as well as packages of measures to consider interactive effects between multiple measures. The large scale EnergyPlus simulations are being conducted on the super computers at the National Energy Research Scientific Computing Center of Lawrence Berkeley National Laboratory. The pre-simulation database is a part of an on-going project to develop a web-based retrofit toolkit for small and medium-sized commercial buildings in California, which provides real-time energy retrofit feedback by querying DEEP with recommended measures, estimated energy savings and financial payback period based on users’ decision criteria of maximizing energy savings, energy cost savings, carbon reduction, or payback of investment. The pre-simulated database and associated comprehensive measure analysis enhances the ability to performance assessments of retrofits to reduce energy use for small and medium buildings and business owners who typically do not have resources to conduct costly building energy audit. DEEP will be migrated into the DEnCity - DOE’s Energy City, which integrates large-scale energy data for multi-purpose, open, and dynamic database leveraging diverse source of existing simulation data.« less

Commercial Building Energy Asset Score Program Overview and Technical Protocol (Version 1.1)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Na; Goel, Supriya; Makhmalbaf, Atefe

The U.S. Department of Energy (DOE) is developing a voluntary national scoring system for commercial buildings to help building owners and managers assess a building’s energy-related systems independent of operations. The goal of the score is to facilitate cost-effective investment in energy efficiency improvements of commercial buildings. The system, known as the Commercial Building Energy Asset Score, will allow building owners and managers to compare their building infrastructure against peers and track building upgrades over time. The system will also help other building stakeholders (e.g., building investors, tenants, financiers, and appraisers) understand the relative efficiency of different buildings in amore » way that is independent from operations and occupancy. This report outlines the technical protocol used to generate the energy asset score, explains the scoring methodology, and provides additional details regarding the energy asset scoring tool. The alternative methods that were considered prior to developing the current approach are described in the Program Overview and Technical Protocol Version 1.0.« less

Understanding Building Infrastructure and Building Operation through DOE Asset Score Model: Lessons Learned from a Pilot Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Na; Goel, Supriya; Gorrissen, Willy J.

2013-06-24

The U.S. Department of Energy (DOE) is developing a national voluntary energy asset score system to help building owners to evaluate the as-built physical characteristics (including building envelope, the mechanical and electrical systems) and overall building energy efficiency, independent of occupancy and operational choices. The energy asset score breaks down building energy use information by simulating building performance under typical operating and occupancy conditions for a given use type. A web-based modeling tool, the energy asset score tool facilitates the implementation of the asset score system. The tool consists of a simplified user interface built on a centralized simulation enginemore » (EnergyPlus). It is intended to reduce both the implementation cost for the users and increase modeling standardization compared with an approach that requires users to build their own energy models. A pilot project with forty-two buildings (consisting mostly offices and schools) was conducted in 2012. This paper reports the findings. Participants were asked to collect a minimum set of building data and enter it into the asset score tool. Participants also provided their utility bills, existing ENERGY STAR scores, and previous energy audit/modeling results if available. The results from the asset score tool were compared with the building energy use data provided by the pilot participants. Three comparisons were performed. First, the actual building energy use, either from the utility bills or via ENERGY STAR Portfolio Manager, was compared with the modeled energy use. It was intended to examine how well the energy asset score represents a building’s system efficiencies, and how well it is correlated to a building’s actual energy consumption. Second, calibrated building energy models (where they exist) were used to examine any discrepancies between the asset score model and the pilot participant buildings’ [known] energy use pattern. This comparison examined the end use breakdowns and more detailed time series data. Third, ASHRAE 90.1 prototype buildings were also used as an industry standard modeling approach to test the accuracy level of the asset score tool. Our analysis showed that the asset score tool, which uses simplified building simulation, could provide results comparable to a more detailed energy model. The buildings’ as-built efficiency can be reflected in the energy asset score. An analysis between the modeled energy use through the asset score tool and the actual energy use from the utility bills can further inform building owners about the effectiveness of their building’s operation and maintenance.« less

Simulation and visualization of energy-related occupant behavior in office buildings

DOE PAGES

Chen, Yixing; Liang, Xin; Hong, Tianzhen; ...

2017-03-15

In current building performance simulation programs, occupant presence and interactions with building systems are over-simplified and less indicative of real world scenarios, contributing to the discrepancies between simulated and actual energy use in buildings. Simulation results are normally presented using various types of charts. However, using those charts, it is difficult to visualize and communicate the importance of occupants’ behavior to building energy performance. This study introduced a new approach to simulating and visualizing energy-related occupant behavior in office buildings. First, the Occupancy Simulator was used to simulate the occupant presence and movement and generate occupant schedules for each spacemore » as well as for each occupant. Then an occupant behavior functional mockup unit (obFMU) was used to model occupant behavior and analyze their impact on building energy use through co-simulation with EnergyPlus. Finally, an agent-based model built upon AnyLogic was applied to visualize the simulation results of the occupant movement and interactions with building systems, as well as the related energy performance. A case study using a small office building in Miami, FL was presented to demonstrate the process and application of the Occupancy Simulator, the obFMU and EnergyPlus, and the AnyLogic module in simulation and visualization of energy-related occupant behaviors in office buildings. Furthermore, the presented approach provides a new detailed and visual way for policy makers, architects, engineers and building operators to better understand occupant energy behavior and their impact on energy use in buildings, which can improve the design and operation of low energy buildings.« less

Simulation and visualization of energy-related occupant behavior in office buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Yixing; Liang, Xin; Hong, Tianzhen

In current building performance simulation programs, occupant presence and interactions with building systems are over-simplified and less indicative of real world scenarios, contributing to the discrepancies between simulated and actual energy use in buildings. Simulation results are normally presented using various types of charts. However, using those charts, it is difficult to visualize and communicate the importance of occupants’ behavior to building energy performance. This study introduced a new approach to simulating and visualizing energy-related occupant behavior in office buildings. First, the Occupancy Simulator was used to simulate the occupant presence and movement and generate occupant schedules for each spacemore » as well as for each occupant. Then an occupant behavior functional mockup unit (obFMU) was used to model occupant behavior and analyze their impact on building energy use through co-simulation with EnergyPlus. Finally, an agent-based model built upon AnyLogic was applied to visualize the simulation results of the occupant movement and interactions with building systems, as well as the related energy performance. A case study using a small office building in Miami, FL was presented to demonstrate the process and application of the Occupancy Simulator, the obFMU and EnergyPlus, and the AnyLogic module in simulation and visualization of energy-related occupant behaviors in office buildings. Furthermore, the presented approach provides a new detailed and visual way for policy makers, architects, engineers and building operators to better understand occupant energy behavior and their impact on energy use in buildings, which can improve the design and operation of low energy buildings.« less

U.S.– India Joint Center for Building Energy Research and Development (CBERD) Caring for the Energy Health of Healthcare Facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Reshma; Mathew, Paul; Granderson, Jessica

The U.S.-India Joint Center for Building Energy Research & Development (CBERD), created through the Partnership to Accelerate Clean Energy (PACE) agreement between the United States and India, is a research and development (R&D) center with over 30 institutional and industry partners from both nations. This five-year presidential initiative is jointly funded by the U.S. Department of Energy and the Government of India. CBERD aims to build upon a foundation of collaborative knowledge, tools, and technologies, and human capabilities that will increase development of high-performance buildings. To reach this goal, the R&D focuses on energy use reduction throughout the entire lifemore » cycle of buildings—i.e., design, construction, and operations. During the operations phase of buildings, even with best-practice energy-efficient design, actual energy use can be much higher than the design intent. Every day, much of the energy consumed by buildings serves no purpose (Roth et al. 2005). Building energy information systems (EIS) are commercially available systems that building owners and facility managers use to assess their building operations, measure, visualize, analyze, and report energy cost and consumption. Energy information systems can enable significant energy savings by tracking energy use, identifying consumption patterns, and benchmarking performance against similar buildings, thereby identifying improvement opportunities. The CBERD team has identified potential energy savings of approximately 2 quads of primary energy in the United States, while industry building energy audits in India have indicated potential energy savings of up to 30 percent in commercial buildings such as offices. Additionally, the CBERD team has identified healthcare facilities (e.g., hospitals, clinics), hotels, and offices as the three of the highest-growth sectors in India that have significant energy consumption, and that would benefit the most from implementation of EIS.« less

Early Design Energy Analysis Using Building Information Modeling Technology

DTIC Science & Technology

2011-11-01

building, (a) floor plan and (b) 3D image. ....................................... 50 Figure 28. Comparison of different energy estimates...when they make the biggest impact on building life-cycle costs. Traditionally, most building energy analyses have been conducted late in design, by...complete energy analysis. This method enables project teams to make energy conscious decisions early in design when they impact building life-cycle

The Effectiveness of Taiwan Building Energy Regulation under the influence of Future Climate

NASA Astrophysics Data System (ADS)

Weng, Yu-Teng; Huang, Kuo-Tsang

2017-04-01

Building energy consumption comprises circa 40% of the national annual energy usage in Taiwan, and the majority proportion is attributed to the cooling apparatus usage. As cooling energy is closely related to the outdoor climate, it is expected that the future global climate change would amplify its demand. Considering the building energy regulation criteria are the minimum requirements that the building has to be complied with, this study tried to investigate whether the current building energy regulation in Taiwan, initiated in 2013, would still be capable of maintaining the energy use in the future as today's level. The research adopted EnergyPlus to simulate the annual cooling energy use of several virtual office building cases with the constructed hourly future weather data under future climate change scenarios of RCP45 and RCP85 defined by IPCC. The virtual building cases are generated by a structured orthogonal array with each case is constituted by 10 building design parameters. The results revealed that the building energy consumption based on the current regulation criteria failed to maintain at the same level in the future as oppose to nowadays. By comparing to the current cooling energy usage, it would rise by 13% and 22% in RCP45 and RCP85, respectively, at the end of this century. This research further parametrically studied the potential cooling energy mitigation strategies and proposed effective building envelope design schemes in order to neutralize the future building energy increase.

75 FR 17700 - Energy Efficient Building Systems Regional Innovation Cluster Initiative-Joint Federal Funding...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-07

... economically dynamic regional innovation cluster focused on energy efficient buildings technologies and systems... DEPARTMENT OF ENERGY Energy Efficient Building Systems Regional Innovation Cluster Initiative... February 8, 2010, titled the Energy Efficient Building Systems Regional Innovation Cluster Initiative. A...

DEEP: Database of Energy Efficiency Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Tianzhen; Piette, Mary; Lee, Sang Hoon

A database of energy efficiency performance (DEEP) is a presimulated database to enable quick and accurate assessment of energy retrofit of commercial buildings. DEEP was compiled from results of about 10 million EnergyPlus simulations. DEEP provides energy savings for screening and evaluation of retrofit measures targeting the small and medium-sized office and retail buildings in California. The prototype building models are developed for a comprehensive assessment of building energy performance based on DOE commercial reference buildings and the California DEER [sic] prototype buildings. The prototype buildings represent seven building types across six vintages of constructions and 16 California climate zones.more » DEEP uses these prototypes to evaluate energy performance of about 100 energy conservation measures covering envelope, lighting, heating, ventilation, air conditioning, plug loads, and domestic hot war. DEEP consists the energy simulation results for individual retrofit measures as well as packages of measures to consider interactive effects between multiple measures. The large scale EnergyPlus simulations are being conducted on the super computers at the National Energy Research Scientific Computing Center (NERSC) of Lawrence Berkeley National Laboratory. The pre-simulation database is a part of the CEC PIER project to develop a web-based retrofit toolkit for small and medium-sized commercial buildings in California, which provides real-time energy retrofit feedback by querying DEEP with recommended measures, estimated energy savings and financial payback period based on users' decision criteria of maximizing energy savings, energy cost savings, carbon reduction, or payback of investment. The pre-simulated database and associated comprehensive measure analysis enhances the ability to performance assessments of retrofits to reduce energy use for small and medium buildings and business owners who typically do not have resources to conduct costly building energy audit.« less

Commercial Buildings Energy Consumption Survey - Office Buildings

EIA Publications

2010-01-01

Provides an in-depth look at this building type as reported in the 2003 Commercial Buildings Energy Consumption Survey. Office buildings are the most common type of commercial building and they consumed more than 17% of all energy in the commercial buildings sector in 2003. This special report provides characteristics and energy consumption data by type of office building (e.g. administrative office, government office, medical office) and information on some of the types of equipment found in office buildings: heating and cooling equipment, computers, servers, printers, and photocopiers.

Commercial Buildings Energy Consumption Survey (CBECS)

EIA Publications

2028-01-01

The Commercial Buildings Energy Consumption Survey (CBECS) is a national sample survey that collects information on the stock of U.S. commercial buildings, including their energy-related building characteristics and energy usage data (consumption and expenditures). Commercial buildings include all buildings in which at least half of the floorspace is used for a purpose that is not residential, industrial, or agricultural. By this definition, CBECS includes building types that might not traditionally be considered commercial, such as schools, hospitals, correctional institutions, and buildings used for religious worship, in addition to traditional commercial buildings such as stores, restaurants, warehouses, and office buildings.

Building Energy Monitoring and Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Tianzhen; Feng, Wei; Lu, Alison

U.S. and China are the world’s top two economics. Together they consumed one-third of the world’s primary energy. It is an unprecedented opportunity and challenge for governments, researchers and industries in both countries to join together to address energy issues and global climate change. Such joint collaboration has huge potential in creating new jobs in energy technologies and services. Buildings in the US and China consumed about 40% and 25% of the primary energy in both countries in 2010 respectively. Worldwide, the building sector is the largest contributor to the greenhouse gas emission. Better understanding and improving the energy performancemore » of buildings is a critical step towards sustainable development and mitigation of global climate change. This project aimed to develop a standard methodology for building energy data definition, collection, presentation, and analysis; apply the developed methods to a standardized energy monitoring platform, including hardware and software, to collect and analyze building energy use data; and compile offline statistical data and online real-time data in both countries for fully understanding the current status of building energy use. This helps decode the driving forces behind the discrepancy of building energy use between the two countries; identify gaps and deficiencies of current building energy monitoring, data collection, and analysis; and create knowledge and tools to collect and analyze good building energy data to provide valuable and actionable information for key stakeholders.« less

Establishing a commercial building energy data framework for India

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iyer, Maithili; Kumar, Satish; Mathew, Sangeeta

Buildings account for over 40% of the world’s energy consumption and are therefore a key contributor to a country’s energy as well as carbon budget. Understanding how buildings use energy is critical to understanding how related policies may impact energy use. Data enables decision making, and good quality data arms consumers with the tools to compare their energy performance to their peers, allowing them to differentiate their buildings in the real estate market on the basis of their energy footprint. Good quality data are also essential for policy makers to prioritize their energy saving strategies and track implementation. The Unitedmore » States’ Commercial Building Energy Consumption Survey (CBECS) is an example of a successful data framework that is highly useful for governmental and nongovernmental initiatives related to benchmarking energy forecasting, rating systems and metrics, and more. The Bureau of Energy Efficiency (BEE) in India developed the Energy Conservation Building Code (ECBC) and launched the Star Labeling program for a few energy-intensive building segments as a significant first step. However, a data driven policy framework for systematically targeting energy efficiency in both new construction and existing buildings has largely been missing. There is no quantifiable mechanism currently in place to track the impact of code adoption through regular reporting/survey of energy consumption in the commercial building stock. In this paper we present findings from our study that explored use cases and approaches for establishing a commercial buildings data framework for India.« less

Deep carbon reductions in California require electrification and integration across economic sectors

NASA Astrophysics Data System (ADS)

Wei, Max; Nelson, James H.; Greenblatt, Jeffery B.; Mileva, Ana; Johnston, Josiah; Ting, Michael; Yang, Christopher; Jones, Chris; McMahon, James E.; Kammen, Daniel M.

2013-03-01

Meeting a greenhouse gas (GHG) reduction target of 80% below 1990 levels in the year 2050 requires detailed long-term planning due to complexity, inertia, and path dependency in the energy system. A detailed investigation of supply and demand alternatives is conducted to assess requirements for future California energy systems that can meet the 2050 GHG target. Two components are developed here that build novel analytic capacity and extend previous studies: (1) detailed bottom-up projections of energy demand across the building, industry and transportation sectors; and (2) a high-resolution variable renewable resource capacity planning model (SWITCH) that minimizes the cost of electricity while meeting GHG policy goals in the 2050 timeframe. Multiple pathways exist to a low-GHG future, all involving increased efficiency, electrification, and a dramatic shift from fossil fuels to low-GHG energy. The electricity system is found to have a diverse, cost-effective set of options that meet aggressive GHG reduction targets. This conclusion holds even with increased demand from transportation and heating, but the optimal levels of wind and solar deployment depend on the temporal characteristics of the resulting load profile. Long-term policy support is found to be a key missing element for the successful attainment of the 2050 GHG target in California.

Analytical sizing methods for behind-the-meter battery storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Di; Kintner-Meyer, Michael; Yang, Tao

In behind-the-meter application, battery storage system (BSS) is utilized to reduce a commercial or industrial customer’s payment for electricity use, including energy charge and demand charge. The potential value of BSS in payment reduction and the most economic size can be determined by formulating and solving standard mathematical programming problems. In this method, users input system information such as load profiles, energy/demand charge rates, and battery characteristics to construct a standard programming problem that typically involve a large number of constraints and decision variables. Such a large scale programming problem is then solved by optimization solvers to obtain numerical solutions.more » Such a method cannot directly link the obtained optimal battery sizes to input parameters and requires case-by-case analysis. In this paper, we present an objective quantitative analysis of costs and benefits of customer-side energy storage, and thereby identify key factors that affect battery sizing. Based on the analysis, we then develop simple but effective guidelines that can be used to determine the most cost-effective battery size or guide utility rate design for stimulating energy storage development. The proposed analytical sizing methods are innovative, and offer engineering insights on how the optimal battery size varies with system characteristics. We illustrate the proposed methods using practical building load profile and utility rate. The obtained results are compared with the ones using mathematical programming based methods for validation.« less

Optimizing Natural Gas Networks through Dynamic Manifold Theory and a Decentralized Algorithm: Belgium Case Study

NASA Astrophysics Data System (ADS)

Koch, Caleb; Winfrey, Leigh

2014-10-01

Natural Gas is a major energy source in Europe, yet political instabilities have the potential to disrupt access and supply. Energy resilience is an increasingly essential construct and begins with transmission network design. This study proposes a new way of thinking about modelling natural gas flow. Rather than relying on classical economic models, this problem is cast into a time-dependent Hamiltonian dynamics discussion. Traditional Natural Gas constraints, including inelastic demand and maximum/minimum pipe flows, are portrayed as energy functions and built into the dynamics of each pipe flow. Doing so allows the constraints to be built into the dynamics of each pipeline. As time progresses in the model, natural gas flow rates find the minimum energy, thus the optimal gas flow rates. The most important result of this study is using dynamical principles to ensure the output of natural gas at demand nodes remains constant, which is important for country to country natural gas transmission. Another important step in this study is building the dynamics of each flow in a decentralized algorithm format. Decentralized regulation has solved congestion problems for internet data flow, traffic flow, epidemiology, and as demonstrated in this study can solve the problem of Natural Gas congestion. A mathematical description is provided for how decentralized regulation leads to globally optimized network flow. Furthermore, the dynamical principles and decentralized algorithm are applied to a case study of the Fluxys Belgium Natural Gas Network.

Relative significance of heat transfer processes to quantify tradeoffs between complexity and accuracy of energy simulations with a building energy use patterns classification

NASA Astrophysics Data System (ADS)

Heidarinejad, Mohammad

This dissertation develops rapid and accurate building energy simulations based on a building classification that identifies and focuses modeling efforts on most significant heat transfer processes. The building classification identifies energy use patterns and their contributing parameters for a portfolio of buildings. The dissertation hypothesis is "Building classification can provide minimal required inputs for rapid and accurate energy simulations for a large number of buildings". The critical literature review indicated there is lack of studies to (1) Consider synoptic point of view rather than the case study approach, (2) Analyze influence of different granularities of energy use, (3) Identify key variables based on the heat transfer processes, and (4) Automate the procedure to quantify model complexity with accuracy. Therefore, three dissertation objectives are designed to test out the dissertation hypothesis: (1) Develop different classes of buildings based on their energy use patterns, (2) Develop different building energy simulation approaches for the identified classes of buildings to quantify tradeoffs between model accuracy and complexity, (3) Demonstrate building simulation approaches for case studies. Penn State's and Harvard's campus buildings as well as high performance LEED NC office buildings are test beds for this study to develop different classes of buildings. The campus buildings include detailed chilled water, electricity, and steam data, enabling to classify buildings into externally-load, internally-load, or mixed-load dominated. The energy use of the internally-load buildings is primarily a function of the internal loads and their schedules. Externally-load dominated buildings tend to have an energy use pattern that is a function of building construction materials and outdoor weather conditions. However, most of the commercial medium-sized office buildings have a mixed-load pattern, meaning the HVAC system and operation schedule dictate the indoor condition regardless of the contribution of internal and external loads. To deploy the methodology to another portfolio of buildings, simulated LEED NC office buildings are selected. The advantage of this approach is to isolate energy performance due to inherent building characteristics and location, rather than operational and maintenance factors that can contribute to significant variation in building energy use. A framework for detailed building energy databases with annual energy end-uses is developed to select variables and omit outliers. The results show that the high performance office buildings are internally-load dominated with existence of three different clusters of low-intensity, medium-intensity, and high-intensity energy use pattern for the reviewed office buildings. Low-intensity cluster buildings benefit from small building area, while the medium- and high-intensity clusters have a similar range of floor areas and different energy use intensities. Half of the energy use in the low-intensity buildings is associated with the internal loads, such as lighting and plug loads, indicating that there are opportunities to save energy by using lighting or plug load management systems. A comparison between the frameworks developed for the campus buildings and LEED NC office buildings indicates these two frameworks are complementary to each other. Availability of the information has yielded to two different procedures, suggesting future studies for a portfolio of buildings such as city benchmarking and disclosure ordinance should collect and disclose minimal required inputs suggested by this study with the minimum level of monthly energy consumption granularity. This dissertation developed automated methods using the OpenStudio API (Application Programing Interface) to create energy models based on the building class. ASHRAE Guideline 14 defines well-accepted criteria to measure accuracy of energy simulations; however, there is no well-accepted methodology to quantify the model complexity without the influence of the energy modeler judgment about the model complexity. This study developed a novel method using two weighting factors, including weighting factors based on (1) computational time and (2) easiness of on-site data collection, to measure complexity of the energy models. Therefore, this dissertation enables measurement of both model complexity and accuracy as well as assessment of the inherent tradeoffs between energy simulation model complexity and accuracy. The results of this methodology suggest for most of the internal load contributors such as operation schedules the on-site data collection adds more complexity to the model compared to the computational time. Overall, this study provided specific data on tradeoffs between accuracy and model complexity that points to critical inputs for different building classes, rather than an increase in the volume and detail of model inputs as the current research and consulting practice indicates. (Abstract shortened by UMI.).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Torcellini, Paul A.; Bonnema, Eric; Goldwasser, David

Building energy consumption can only be measured at the site or at the point of utility interconnection with a building. Often, to evaluate the total energy impact, this site-based energy consumption is translated into source energy, that is, the energy at the point of fuel extraction. Consistent with this approach, the U.S. Department of Energy's (DOE) definition of zero energy buildings uses source energy as the metric to account for energy losses from the extraction, transformation, and delivery of energy. Other organizations, as well, use source energy to characterize the energy impacts. Four methods of making the conversion from sitemore » energy to source energy were investigated in the context of the DOE definition of zero energy buildings. These methods were evaluated based on three guiding principles--improve energy efficiency, reduce and stabilize power demand, and use power from nonrenewable energy sources as efficiently as possible. This study examines relative trends between strategies as they are implemented on very low-energy buildings to achieve zero energy. A typical office building was modeled and variations to this model performed. The photovoltaic output that was required to create a zero energy building was calculated. Trends were examined with these variations to study the impacts of the calculation method on the building's ability to achieve zero energy status. The paper will highlight the different methods and give conclusions on the advantages and disadvantages of the methods studied.« less

Research Support Facility (RSF): Leadership in Building Performance (Brochure)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This brochure/poster provides information on the features of the Research Support Facility including a detailed illustration of the facility with call outs of energy efficiency and renewable energy technologies. Imagine an office building so energy efficient that its occupants consume only the amount of energy generated by renewable power on the building site. The building, the Research Support Facility (RSF) occupied by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) employees, uses 50% less energy than if it were built to current commercial code and achieves the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED{reg_sign})more » Platinum rating. With 19% of the primary energy in the U.S. consumed by commercial buildings, the RSF is changing the way commercial office buildings are designed and built.« less

75 FR 7464 - Energy Efficient Building Systems Regional Innovation Cluster Initiative-Joint Federal Funding...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-19

... DEPARTMENT OF ENERGY Energy Efficient Building Systems Regional Innovation Cluster Initiative... Energy Efficient Building Systems Regional Innovation Cluster Initiative. A single proposal submitted by... systems design. The DOE funded Energy Efficient Building Systems Design Hub (the ``Hub'') will serve as a...

Energy in buildings: Efficiency, renewables and storage

NASA Astrophysics Data System (ADS)

Koebel, Matthias M.

2017-07-01

This lecture summary provides a short but comprehensive overview on the "energy and buildings" topic. Buildings account for roughly 40% of the global energy demands. Thus, an increased adoption of existing and upcoming materials and solutions for the building sector represents an enormous potential to reduce building related energy demands and greenhouse gas emissions. The central question is how the building envelope (insulation, fenestration, construction style, solar control) affects building energy demands. Compared to conventional insulation materials, superinsulation materials such as vacuum insulation panels and silica aerogel achieve the same thermal performance with significantly thinner insulation layers. With low-emissivity coatings and appropriate filler gasses, double and triple glazing reduce thermal losses by up to an order of magnitude compared to old single pane windows, while vacuum insulation and aerogel filled glazing could reduce these even further. Electrochromic and other switchable glazing solutions maximize solar gains during wintertime and minimize illumination demands whilst avoiding overheating in summer. Upon integration of renewable energy systems into the building energy supply, buildings can become both producers and consumers of energy. Combined with dynamic user behavior, temporal variations in the production of renewable energy require appropriate storage solutions, both thermal and electrical, and the integration of buildings into smart grids and energy district networks. The combination of these measures allows a reduction of the existing building stock by roughly a factor of three —a promising, but cost intensive way, to prepare our buildings for the energy turnaround.

Advanced human-machine interface for collaborative building control

DOEpatents

Zheng, Xianjun S.; Song, Zhen; Chen, Yanzi; Zhang, Shaopeng; Lu, Yan

2015-08-11

A system for collaborative energy management and control in a building, including an energy management controller, one or more occupant HMIs that supports two-way communication between building occupants and a facility manager, and between building occupants and the energy management controller, and a facility manager HMI that supports two-way communication between the facility manager and the building occupants, and between the facility manager and the energy management controller, in which the occupant HMI allows building occupants to provide temperature preferences to the facility manager and the energy management controller, and the facility manager HMI allows the facility manager to configure an energy policy for the building as a set of rules and to view occupants' aggregated temperature preferences, and the energy management controller determines an optimum temperature range that resolves conflicting occupant temperature preferences and occupant temperature preferences that conflict with the facility manager's energy policy for the building.

Data-Driven Benchmarking of Building Energy Efficiency Utilizing Statistical Frontier Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kavousian, A; Rajagopal, R

2014-01-01

Frontier methods quantify the energy efficiency of buildings by forming an efficient frontier (best-practice technology) and by comparing all buildings against that frontier. Because energy consumption fluctuates over time, the efficiency scores are stochastic random variables. Existing applications of frontier methods in energy efficiency either treat efficiency scores as deterministic values or estimate their uncertainty by resampling from one set of measurements. Availability of smart meter data (repeated measurements of energy consumption of buildings) enables using actual data to estimate the uncertainty in efficiency scores. Additionally, existing applications assume a linear form for an efficient frontier; i.e.,they assume that themore » best-practice technology scales up and down proportionally with building characteristics. However, previous research shows that buildings are nonlinear systems. This paper proposes a statistical method called stochastic energy efficiency frontier (SEEF) to estimate a bias-corrected efficiency score and its confidence intervals from measured data. The paper proposes an algorithm to specify the functional form of the frontier, identify the probability distribution of the efficiency score of each building using measured data, and rank buildings based on their energy efficiency. To illustrate the power of SEEF, this paper presents the results from applying SEEF on a smart meter data set of 307 residential buildings in the United States. SEEF efficiency scores are used to rank individual buildings based on energy efficiency, to compare subpopulations of buildings, and to identify irregular behavior of buildings across different time-of-use periods. SEEF is an improvement to the energy-intensity method (comparing kWh/sq.ft.): whereas SEEF identifies efficient buildings across the entire spectrum of building sizes, the energy-intensity method showed bias toward smaller buildings. The results of this research are expected to assist researchers and practitioners compare and rank (i.e.,benchmark) buildings more robustly and over a wider range of building types and sizes. Eventually, doing so is expected to result in improved resource allocation in energy-efficiency programs.« less

Control Limits for Building Energy End Use Based on Engineering Judgment, Frequency Analysis, and Quantile Regression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henze, Gregor P.; Pless, Shanti; Petersen, Anya

2014-02-01

Approaches are needed to continuously characterize the energy performance of commercial buildings to allow for (1) timely response to excess energy use by building operators; and (2) building occupants to develop energy awareness and to actively engage in reducing energy use. Energy information systems, often involving graphical dashboards, are gaining popularity in presenting energy performance metrics to occupants and operators in a (near) real-time fashion. Such an energy information system, called Building Agent, has been developed at NREL and incorporates a dashboard for public display. Each building is, by virtue of its purpose, location, and construction, unique. Thus, assessing buildingmore » energy performance is possible only in a relative sense, as comparison of absolute energy use out of context is not meaningful. In some cases, performance can be judged relative to average performance of comparable buildings. However, in cases of high-performance building designs, such as NREL's Research Support Facility (RSF) discussed in this report, relative performance is meaningful only when compared to historical performance of the facility or to a theoretical maximum performance of the facility as estimated through detailed building energy modeling.« less