78 FR 61999 - Hydropower Regulatory Efficiency Act of 2013; Supplemental Notice of Workshop

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-10

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. AD13-9-000] Hydropower Regulatory Efficiency Act of 2013; Supplemental Notice of Workshop As announced in the Notices issued on September 3, 2013 and September 18, 2013, the Federal Energy Regulatory Commission (FERC or Commission...

Summary of Needs and Opportunities from the 2011 Residential Energy Efficiency Stakeholders Meeting: Atlanta, Georgia -- March 16-18, 2011

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

Not Available

This summary report outlines needs and issues for increasing energy efficiency of new and existing U.S homes, as identified at the U.S Department of Energy Building America program Spring 2011 stakeholder meeting in Atlanta, Georgia.

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

NONE

The report is an overview of electric energy efficiency programs. It takes a concise look at what states are doing to encourage energy efficiency and how it impacts electric utilities. Energy efficiency programs began to be offered by utilities as a response to the energy crises of the 1970s. These regulatory-driven programs peaked in the early-1990s and then tapered off as deregulation took hold. Today, rising electricity prices, environmental concerns, and national security issues have renewed interest in increasing energy efficiency as an alternative to additional supply. In response, new methods for administering, managing, and delivering energy efficiency programs aremore » being implemented. Topics covered in the report include: Analysis of the benefits of energy efficiency and key methods for achieving energy efficiency; evaluation of the business drivers spurring increased energy efficiency; Discussion of the major barriers to expanding energy efficiency programs; evaluation of the economic impacts of energy efficiency; discussion of the history of electric utility energy efficiency efforts; analysis of the impact of energy efficiency on utility profits and methods for protecting profitability; Discussion of non-utility management of energy efficiency programs; evaluation of major methods to spur energy efficiency - systems benefit charges, resource planning, and resource standards; and, analysis of the alternatives for encouraging customer participation in energy efficiency programs.« less

Interlocal collaboration on energy efficiency, sustainability and climate change issues

NASA Astrophysics Data System (ADS)

Chen, Ssu-Hsien

Interlocal energy collaboration builds upon network structures among local policy actors dealing with energy, climate change and sustainability issues. Collaboration efforts overcome institutional collective action (ICA) dilemmas, and cope with the problems spanning jurisdictional boundaries, externalities, and free-rider problems. Interlocal energy collaboration emerges as the agreements in greenhouse gas (GHG) emission reduction, pollution control, land use, purchasing, retrofits, transportation, and so forth. Cities work collaboratively through contractual mechanisms (i.e. formal/informal agreements) and collective mechanisms (i.e. regional partnerships or membership organizations) on a variety of energy issues. What factors facilitate interlocal energy collaboration? To what extent is collaboration through interlocal contractual mechanisms different from collective mechanisms? This dissertation tries to answer these questions by examining: city goal priority on energy related issues as well as other ICA explanatory factors. Research data are drawn mainly from the 2010 national survey "Implementation of energy efficiency and sustainability program" supported by National Science Foundation and the IBM Endowment for the Business of Government. The research results show that city emphasis on common pool resource, scale economies and externality issues significantly affect individual selection of tools for energy collaboration. When expected transaction costs are extremely high or low, the contractual mechanism of informal agreement is more likely to be selected to preserve most local autonomy and flexibility; otherwise, written and formal tools for collaboration are preferred to impose constraints on individual behavior and reduce the risks of defection.

Introduction to energy sources. [Monograph

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

Not Available

1978-01-01

Energy resources are reviewed in lay terms in an effort to increase the public's awareness of energy issues. Summaries of the principal sources of energy describe availability, technological requirements, and environmental impacts. The emphasis is placed on making energy use more efficient and the implications of shifting to centralized power plants, with more reliance on electricity. The purpose of this monograph is to demonstrate that energy issues can be examined and assessed by non-experts.

78 FR 11996 - Energy Efficiency Program for Commercial and Industrial Equipment: Commercial and Industrial Pumps

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-21

.... EERE-2011-BT-STD-0031] RIN 1904-AC54 Energy Efficiency Program for Commercial and Industrial Equipment... meeting and availability of the Framework Document pertaining to the development of energy conservation... to and the issues presented by these equipment types, and in consideration of the travel schedules of...

Wind-To-Hydrogen Project: Electrolyzer Capital Cost Study

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

Saur, G.

This study is being performed as part of the U.S. Department of Energy and Xcel Energy's Wind-to-Hydrogen Project (Wind2H2) at the National Renewable Energy Laboratory. The general aim of the project is to identify areas for improving the production of hydrogen from renewable energy sources. These areas include both technical development and cost analysis of systems that convert renewable energy to hydrogen via water electrolysis. Increased efficiency and reduced cost will bring about greater market penetration for hydrogen production and application. There are different issues for isolated versus grid-connected systems, however, and these issues must be considered. The manner inmore » which hydrogen production is integrated in the larger energy system will determine its cost feasibility and energy efficiency.« less

48 CFR 23.602 - Contract clause.

Code of Federal Regulations, 2012 CFR

2012-10-01

... PROGRAMS ENVIRONMENT, ENERGY AND WATER EFFICIENCY, RENEWABLE ENERGY TECHNOLOGIES, OCCUPATIONAL SAFETY, AND... regulations issued pursuant to the Atomic Energy Act of 1954; or (b) radioactive material not requiring...

Energy efficiency and conservation in the developing world. World Bank policy paper. Energia: Eficiencia y conservacion en el mundo en desarrollo

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

Not Available

1993-01-01

Energy demand and production in developing countries are up, but efficiency of production and consumption are falling behind. The paper explores that issue and reviews the Bank's participation in energy projects. The paper conveys the Bank's strategy to promote efficiency through such means as transferring modern technology from the industrial countries and lending more selectively to energy-supply enterprises. The Bank identifies four factors that account for the differences in efficiency between the industrial and developing countries: energy pricing policies, control of energy supply enterprises, protection of energy-using industry from competition, and barriers to the productive functioning of markets.

Green buildings need good ergonomics.

PubMed

Hedge, A; Dorsey, J A

2013-01-01

A retrospective post-occupancy evaluation survey of 44 occupants in two Leadership in Energy and Environmental Design (LEED) Platinum buildings on a US college campus is reported. The Internet survey covered a range of indoor environment and ergonomics issues. Results show that working in these buildings were a generally positive experience for their health, performance and satisfaction. However, in one building there were persistent issues of variability in air temperature, air freshness, air quality and noise that affected the perceived health and performance of the occupants. Although the buildings were energy-efficient and sustainable structures, ergonomics design issues were identified. Implications for the role of ergonomics in green buildings and in the US LEED rating system are discussed. This survey identified a number of ergonomics design issues present in the LEED Platinum energy-efficient and sustainable buildings that were studied. These results highlight the importance of integrating ergonomics design into green buildings as a component in the US LEED rating system.

Mitigation of Greenhouse Gases in the Southeast USA

Treesearch

Kenneth L. Mitchell; Kimberly M. Adelberg; Marilyn Brown; Ryan Brown; Diana Burk; Cort Cooper; Jeffrey S. Gaffney; Garry P. Garrett; Daniel Garver; Stephen A. Smith; Ge Sun; Thomas Wells

2013-01-01

Key IssuesContinued investment in clean energy, including energy efficiency and clean energy supply options, including for transportation.Maintenance of carbon sinks in the face of development pressures.

Scalable Energy Efficiency with Resilience for High Performance Computing Systems: A Quantitative Methodology

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

Tan, Li; Chen, Zizhong; Song, Shuaiwen

2016-01-18

Energy efficiency and resilience are two crucial challenges for HPC systems to reach exascale. While energy efficiency and resilience issues have been extensively studied individually, little has been done to understand the interplay between energy efficiency and resilience for HPC systems. Decreasing the supply voltage associated with a given operating frequency for processors and other CMOS-based components can significantly reduce power consumption. However, this often raises system failure rates and consequently increases application execution time. In this work, we present an energy saving undervolting approach that leverages the mainstream resilience techniques to tolerate the increased failures caused by undervolting.

Investigating the Interplay between Energy Efficiency and Resilience in High Performance Computing

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

Tan, Li; Song, Shuaiwen; Wu, Panruo

2015-05-29

Energy efficiency and resilience are two crucial challenges for HPC systems to reach exascale. While energy efficiency and resilience issues have been extensively studied individually, little has been done to understand the interplay between energy efficiency and resilience for HPC systems. Decreasing the supply voltage associated with a given operating frequency for processors and other CMOS-based components can significantly reduce power consumption. However, this often raises system failure rates and consequently increases application execution time. In this work, we present an energy saving undervolting approach that leverages the mainstream resilience techniques to tolerate the increased failures caused by undervolting.

Scalable Energy Efficiency with Resilience for High Performance Computing Systems: A Quantitative Methodology

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

Tan, Li; Chen, Zizhong; Song, Shuaiwen Leon

2015-11-16

Energy efficiency and resilience are two crucial challenges for HPC systems to reach exascale. While energy efficiency and resilience issues have been extensively studied individually, little has been done to understand the interplay between energy efficiency and resilience for HPC systems. Decreasing the supply voltage associated with a given operating frequency for processors and other CMOS-based components can significantly reduce power consumption. However, this often raises system failure rates and consequently increases application execution time. In this work, we present an energy saving undervolting approach that leverages the mainstream resilience techniques to tolerate the increased failures caused by undervolting.

Greens, suits, and bureaucrats: A sociological study of dynamic organizational relationships in energy efficient appliance policy

NASA Astrophysics Data System (ADS)

Shwom-Evelich, Rachael Leah

In this dissertation I develop an approach to understanding dynamic organizational relations and the processes of environmental degradation and reform. To do this, I draw on environmental and organizational sociology to inform an empirical study of interorganizational relationships in defining and promoting energy efficient appliances in the United States (US). The dissertation follows a three paper approach which involves (a) an overall introduction to the substantive issue of appliance energy efficiency in the US; (b) producing three separate and stand alone articles of publishable quality to be submitted to professional journals; and (c) an overall conclusion. The three articles are as follows: (1) a synthetic literature review identifying five lessons that organizational sociology and environmental sociology can learn from each other to advance our sociological understanding of organizations, energy issues, and climate change (2) a qualitative case study of the changing relationships between business, government and environmental and energy advocacy organizations around mandatory appliance efficiency standards supporting the development of a context-dependent theory of ecological modernization and treadmill of production theories in environmental sociology and (3) a network analysis of public government, business and energy efficiency advocate's interorganizational relationships and its influence on subsequent organizational behaviors in the appliance energy efficiency field. The second and third articles are based on extensive archival research on organizational negotiations of public record over defining energy efficient appliances in both regulatory and voluntary settings. Finally I will provide an overall conclusion that brings together the most significant findings of each individual article in anticipation of a synthetic approach to the study of organizations in environmental reform.

Catalyzing Gender Equality-Focused Clean Energy Development in West Africa

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

The Economic Community of West African States (ECOWAS) Regional Center for Renewable Energy and Energy Efficiency (ECREEE) partnered with the Clean Energy Solutions Center (Solutions Center), the African Development Bank and other institutions to develop a Situation Analysis of Energy and Gender Issues in ECOWAS Member States. Through a systematic approach to assess interlinked gender and energy issues in the region, the report puts forth a number of key findings. This brochure highlights ECREEE's partnership with the Solutions Center and key findings from the report.

Technical Assistance for States | State, Local, and Tribal Governments |

Science.gov Websites

on energy efficiency and renewable energy policies and issues for state and local government decision issues for state and local government decision makers. The expert assistance is intended to support legislators, regulators, state agencies, and their staff members in making informed decisions about solar

Transformative research issues and opportunities in energy efficiency

USDA-ARS?s Scientific Manuscript database

This article presents a summary of research opportunities in energy efficiency identified in a workshop by a panel of experts assembled for the Civil, Mechanical and Manufacturing Innovation Division of the U.S. National Science Foundation. The workshop and article are restricted to two areas – red...

Research on data collection key technology of smart electric energy meters

NASA Astrophysics Data System (ADS)

Chen, Xiangqun; Huang, Rui; Shen, Liman; Chen, Hao; Xiong, Dezhi; Xiao, Xiangqi; Mouhailiu; Renheng, Xu

2018-02-01

In recent years, smart electric energy meters are demand at 70 million to 90 million with the strong smart grid construction every year in China. However, there are some issues in smart electric energy meters data collection such as the interference of environment, low collection efficiency and inability to work when the power is off. In order to solve these issues above, it uses the RFID communication technology to collect the numbers and electric energy information of smart electric energy meters on the basis of the existing smart electric energy meters, and the related data collection communication experiments were made. The experimental result shows that the electric information and other data batch collection of RFID smart electric energy meters are realized in power and power off. It improves the efficiency and the overall success rate is 99.2% within 2 meters. It provides a new method for smart electric energy meters data collection.

Leanergy(TM): how lean manufacturing can improve energy efficiency.

PubMed

Riche, Jean-Pierre

2013-01-01

Energy efficiency has become a competitive issue for industrial companies. The evolution of energy prices and regulation will make this issue even more important in the future. For several years, the energy-intensive chemical industry has been implementing corrective actions. Helped by the absorption of base load energy consumption by larger production volumes, specific energy consumption (KWh per production unit) has been significantly reduced in recent years. However, most plants have reached the end of their first action plan based on improving the utilities performance. The Leanergy(TM) method developed by the consultancy company Okavango-energy, is a structured approach based on lean manufacturing which widens the scope of saving sources to process and operations. Starting from the analysis of actual production requirements, Okavango is able to adjust consumption to minimum requirements and so remove any energy consumption that does not contribute to the added value creation.

Franchise Agreements and Clean Energy: Issues in Illinois

EPA Pesticide Factsheets

This project evaluates the impact on energy efficiency of municipal franchise agreements that supply electricity or gas service without a direct charge (unbilled energy) for certain municipal government facilities in Illinois.)

Public policies, private choices: Consumer desire and the practice of energy efficiency

NASA Astrophysics Data System (ADS)

Deumling, Reuben Alexander

Refrigerator energy consumption has been the subject of regulatory attention in the US for some thirty years. Federal product standards, energy labels, and a variety of programs to get consumers to discard their existing refrigerators sooner and buy new, more energy efficient ones have transformed the refrigerator landscape and changed how many of us think about refrigerators. The results of these policies are celebrated as a successful model for how to combine regulatory objectives and consumer preferences in pursuit of environmental outcomes where everyone wins. Yet per capita refrigerator energy consumption today remains (much) higher in the US than anywhere else, in part because energy efficiency overlooks the ways behavior, habit, emulation, social norms, advertising, and energy efficiency policies themselves shape energy consumption patterns. To understand these dynamics I investigate how people replacing their refrigerators through a state-sponsored energy efficiency program make sense of the choices facing them, and how various types of information designed to aid in this process (Consumer Reports tests, Energy Guide labels, rebate programs) frame the issue of responsible refrigerator consumption. Using interviews and archival research I examine how this information is used to script the choice of a refrigerator, whose priorities shape the form and content of these cues, and what the social meanings generated by and through encounters with refrigerators and energy efficiency are. I also helped build a model for estimating historic refrigerator energy consumption in the US, to measure the repercussions of refrigerator energy inefficiency. My focus in this dissertation is on the ways the pursuit of energy efficiency improvements for domestic refrigerators intersects with and sometimes reinforces escalating demand for energy. My research suggests that the practice of pursuing energy efficiency improvements in refrigerators subordinates the issue of refrigerator energy consumption---what factors influence it, how and why it fluctuated historically, how to take it seriously---in pursuit of increased sales. The a priori assumption that consumers desire certain styles of refrigerator has become a compulsion to trade up. In evaluating the results of energy policies celebrating technical achievements without paying attention to the social dynamics which these regulations encounter is insufficient.

International Review of Frameworks for Impact Evaluation of Appliance Standards, Labeling, and Incentives

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

Zhou, Nan; Romankiewicz, John; Vine, Edward

2012-12-15

In recent years, the number of energy efficiency policies implemented has grown very rapidly as energy security and climate change have become top policy issues for many governments around the world. Within the sphere of energy efficiency policy, governments (federal and local), electric utilities, and other types of businesses and institutions are implementing a wide variety of programs to spread energy efficiency practices in industry, buildings, transport, and electricity. As programs proliferate, there is an administrative and business imperative to evaluate the savings and processes of these programs to ensure that program funds spent are indeed leading to a moremore » energy-efficient economy.« less

Answering the Oregon challenge : climate change

DOT National Transportation Integrated Search

2009-01-13

This paper outlines Gov. Kulongoski's agenda concerning the issue of climate change. It addresses several key topics: greenhouse gas reduction, energy efficiency, renewable energy, and sustainable transportation.

Power Conservation through Energy Efficient Routing in Wireless Sensor Networks.

PubMed

Kandris, Dionisis; Tsioumas, Panagiotis; Tzes, Anthony; Nikolakopoulos, George; Vergados, Dimitrios D

2009-01-01

The power awareness issue is the primary concern within the domain of Wireless Sensor Networks (WSNs). Most power dissipation ocurrs during communication, thus routing protocols in WSNs mainly aim at power conservation. Moreover, a routing protocol should be scalable, so that its effectiveness does not degrade as the network size increases. In response to these issues, this work describes the development of an efficient routing protocol, named SHPER (Scaling Hierarchical Power Efficient Routing).

Summary of Needs and Opportunities from the 2011 Residential Energy Efficiency Meeting: Atlanta, Georgia, March 16-18, 2011

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

none,

This meeting brought together more than 200 professionals representing organizations with vested interest in energy efficiency improvements in residential buildings. Participants identified or reinforced a wide variety of needs and issues associated with delivering high-performance homes in both new and existing home scenarios,

Low Li+ Insertion Barrier Carbon for High Energy Efficient Lithium-Ion Capacitor.

PubMed

Lee, Wee Siang Vincent; Huang, Xiaolei; Tan, Teck Leong; Xue, Jun Min

2018-01-17

Lithium-ion capacitor (LIC) is an attractive energy-storage device (ESD) that promises high energy density at moderate power density. However, the key challenge in its design is the low energy efficient negative electrode, which barred the realization of such research system in fulfilling the current ESD technological inadequacy due to its poor overall energy efficiency. Large voltage hysteresis is the main issue behind high energy density alloying/conversion-type materials, which reduces the electrode energy efficiency. Insertion-type material though averted in most research due to the low capacity remains to be highly favorable in commercial application due to its lower voltage hysteresis. To further reduce voltage hysteresis and increase capacity, amorphous carbon with wider interlayer spacing has been demonstrated in the simulation result to significantly reduce Li + insertion barrier. Hence, by employing such amorphous carbon, together with disordered carbon positive electrode, a high energy efficient LIC with round-trip energy efficiency of 84.3% with a maximum energy density of 133 Wh kg -1 at low power density of 210 W kg -1 can be achieved.

A survey on human behavior towards energy efficiency for office worker in malaysia

NASA Astrophysics Data System (ADS)

Mustafa, N. H.; Husain, M. N.; Abd Aziz, M. Z. A.; Othman, M. A.; Malek, F.

2014-04-01

Green environment has become an important topic around the world. This campaign can be realized if everybody understands and shares similar objectives on managing energy in an efficient way. This paper will present and analyse the survey on energy usage by office workers in Malaysia. The survey will focus on the workers in government sector. In social science surveys, it is important to support the tested data for a project. For issues related to human behaviour we must compare with real situations to verify the tested data and the results in energy monitoring system. The energy monitoring system will improve energy usage efficiency for the basic human activities in different situations and environments.

Political ideology affects energy-efficiency attitudes and choices

PubMed Central

Gromet, Dena M.; Kunreuther, Howard; Larrick, Richard P.

2013-01-01

This research demonstrates how promoting the environment can negatively affect adoption of energy efficiency in the United States because of the political polarization surrounding environmental issues. Study 1 demonstrated that more politically conservative individuals were less in favor of investment in energy-efficient technology than were those who were more politically liberal. This finding was driven primarily by the lessened psychological value that more conservative individuals placed on reducing carbon emissions. Study 2 showed that this difference has consequences: In a real-choice context, more conservative individuals were less likely to purchase a more expensive energy-efficient light bulb when it was labeled with an environmental message than when it was unlabeled. These results highlight the importance of taking into account psychological value-based considerations in the individual adoption of energy-efficient technology in the United States and beyond. PMID:23630266

Political ideology affects energy-efficiency attitudes and choices.

PubMed

Gromet, Dena M; Kunreuther, Howard; Larrick, Richard P

2013-06-04

This research demonstrates how promoting the environment can negatively affect adoption of energy efficiency in the United States because of the political polarization surrounding environmental issues. Study 1 demonstrated that more politically conservative individuals were less in favor of investment in energy-efficient technology than were those who were more politically liberal. This finding was driven primarily by the lessened psychological value that more conservative individuals placed on reducing carbon emissions. Study 2 showed that this difference has consequences: In a real-choice context, more conservative individuals were less likely to purchase a more expensive energy-efficient light bulb when it was labeled with an environmental message than when it was unlabeled. These results highlight the importance of taking into account psychological value-based considerations in the individual adoption of energy-efficient technology in the United States and beyond.

75 FR 3454 - Proposed Emergency Agency Information Collection

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-21

... on respondents, including through the use of automated collection techniques or other forms of... improve energy efficiency and reduce energy use and fossil fuel emissions in their communities. Issued in...

48 CFR 23.602 - Contract clause.

Code of Federal Regulations, 2011 CFR

2011-10-01

... PROGRAMS ENVIRONMENT, ENERGY AND WATER EFFICIENCY, RENEWABLE ENERGY TECHNOLOGIES, OCCUPATIONAL SAFETY, AND DRUG-FREE WORKPLACE Notice of Radioactive Material 23.602 Contract clause. The contracting officer... regulations issued pursuant to the Atomic Energy Act of 1954; or (b) radioactive material not requiring...

48 CFR 23.602 - Contract clause.

Code of Federal Regulations, 2013 CFR

2013-10-01

... PROGRAMS ENVIRONMENT, ENERGY AND WATER EFFICIENCY, RENEWABLE ENERGY TECHNOLOGIES, OCCUPATIONAL SAFETY, AND DRUG-FREE WORKPLACE Notice of Radioactive Material 23.602 Contract clause. The contracting officer... regulations issued pursuant to the Atomic Energy Act of 1954; or (b) radioactive material not requiring...

48 CFR 23.602 - Contract clause.

Code of Federal Regulations, 2014 CFR

2014-10-01

... PROGRAMS ENVIRONMENT, ENERGY AND WATER EFFICIENCY, RENEWABLE ENERGY TECHNOLOGIES, OCCUPATIONAL SAFETY, AND DRUG-FREE WORKPLACE Notice of Radioactive Material 23.602 Contract clause. The contracting officer... regulations issued pursuant to the Atomic Energy Act of 1954; or (b) radioactive material not requiring...

ENERGY CONSERVATION AND PRODUCTION AT WASTE CLEANUP SITES (ISSUE PAPER)

EPA Science Inventory

Saving energy used by hazardous waste cleanup remediation systems should interest those people working on waste cleanup sites. Presidential Executive Order 13123, "Greening the Government Through Efficient Energy Management", states that each agency shall strive to expand the us...

48 CFR 23.602 - Contract clause.

Code of Federal Regulations, 2010 CFR

2010-10-01

... PROGRAMS ENVIRONMENT, ENERGY AND WATER EFFICIENCY, RENEWABLE ENERGY TECHNOLOGIES, OCCUPATIONAL SAFETY, AND DRUG-FREE WORKPLACE Notice of Radioactive Material 23.602 Contract clause. The contracting officer... regulations issued pursuant to the Atomic Energy Act of 1954; or (b) radioactive material not requiring...

Energy Efficiency Financing for Low- and Moderate-Income Households: Current State of the Market, Issues, and Opportunities

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

Leventis, Greg; Kramer, Chris; Schwartz, Lisa

Ensuring that low- and moderate-income (LMI) households have access to energy efficiency is equitable, provides energy savings as a resource to meet energy needs, and can support multiple policy goals, such as affordable energy, job creation, and improved public health. Although the need is great, many LMI households may not be able to afford efficiency improvements or may be inhibited from adopting efficiency for other reasons. Decision-makers across the country are currently exploring the challenges and potential solutions to ramping up adoption of efficiency in LMI households, including the use of financing. The report’s objective is to offer state andmore » local policymakers, state utility regulators, program administrators, financial institutions, consumer advocates and other LMI stakeholders with an understanding of: -The relationship between LMI communities and financing for energy efficiency, including important considerations for its use such as consumer protections -The larger programmatic context of grant-based assistance and other related resources supporting LMI household energy efficiency -Lessons learned from existing energy efficiency financing programs serving LMI households -Financing products used by these programs and their relative advantages and disadvantages in addressing barriers to financing or to energy efficiency uptake for LMI households« less

A socio-technical approach to improving retail energy efficiency behaviours.

PubMed

Christina, Sian; Waterson, Patrick; Dainty, Andrew; Daniels, Kevin

2015-03-01

In recent years, the UK retail sector has made a significant contribution to societal responses on carbon reduction. We provide a novel and timely examination of environmental sustainability from a systems perspective, exploring how energy-related technologies and strategies are incorporated into organisational life. We use a longitudinal case study approach, looking at behavioural energy efficiency from within one of the UK's leading retailers. Our data covers a two-year period, with qualitative data from a total of 131 participants gathered using phased interviews and focus groups. We introduce an adapted socio-technical framework approach in order to describe an existing organisational behavioural strategy to support retail energy efficiency. Our findings point to crucial socio-technical and goal-setting factors which both impede and/or enable energy efficient behaviours, these include: tensions linked to store level perception of energy management goals; an emphasis on the importance of technology for underpinning change processes; and, the need for feedback and incentives to support the completion of energy-related tasks. We also describe the evolution of a practical operational intervention designed to address issues raised in our findings. Our study provides fresh insights into how sustainable workplace behaviours can be achieved and sustained over time. Secondly, we discuss in detail a set of issues arising from goal conflict in the workplace; these include the development of a practical energy management strategy to facilitate secondary organisational goals through job redesign. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Supported black phosphorus nanosheets as hydrogen-evolving photocatalyst achieving 5.4% energy conversion efficiency at 353 K.

PubMed

Tian, Bin; Tian, Bining; Smith, Bethany; Scott, M C; Hua, Ruinian; Lei, Qin; Tian, Yue

2018-04-11

Solar-driven water splitting using powdered catalysts is considered as the most economical means for hydrogen generation. However, four-electron-driven oxidation half-reaction showing slow kinetics, accompanying with insufficient light absorption and rapid carrier combination in photocatalysts leads to low solar-to-hydrogen energy conversion efficiency. Here, we report amorphous cobalt phosphide (Co-P)-supported black phosphorus nanosheets employed as photocatalysts can simultaneously address these issues. The nanosheets exhibit robust hydrogen evolution from pure water (pH = 6.8) without bias and hole scavengers, achieving an apparent quantum efficiency of 42.55% at 430 nm and energy conversion efficiency of over 5.4% at 353 K. This photocatalytic activity is attributed to extremely efficient utilization of solar energy (~75% of solar energy) by black phosphorus nanosheets and high-carrier separation efficiency by amorphous Co-P. The hybrid material design realizes efficient solar-to-chemical energy conversion in suspension, demonstrating the potential of black phosphorus-based materials as catalysts for solar hydrogen production.

Energy issues in microwave food processing: A review of developments and the enabling potentials of solid-state power delivery.

PubMed

Atuonwu, J C; Tassou, S A

2018-01-23

The enormous magnitude and variety of microwave applications in household, commercial and industrial food processing creates a strong motivation for improving the energy efficiency and hence, sustainability of the process. This review critically assesses key energy issues associated with microwave food processing, focusing on previous energy performance studies, energy performance metrics, standards and regulations. Factors affecting energy-efficiency are categorised into source, load and source-load matching factors. This highlights the need for highly-flexible and controllable power sources capable of receiving real-time feedback on load properties, and effecting rapid control actions to minimise reflections, heating non-uniformities and other imperfections that lead to energy losses. A case is made for the use of solid-state amplifiers as alternatives to conventional power sources, magnetrons. By a full-scale techno-economic analysis, including energy aspects, it is shown that the use of solid-state amplifiers as replacements to magnetrons is promising, not only from an energy and overall technical perspective, but also in terms of economics.

School Finance. Trends and Issues.

ERIC Educational Resources Information Center

Hadderman, Margaret, Comp.

During the past several years, policymakers and practitioners have concentrated their energies on resolving equity/adequacy issues, reforming school tax structures, improving schools' efficiency and cost-effectiveness, developing school-based accountability, and exploring alternative cost-cutting and fundraising strategies. Total expenditures for…

76 FR 39850 - The Manufacturing Council: Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-07

... development issues, a clean energy standard, energy efficiency, energy regulation reform, trade agreements and..., should be submitted no later than July 14, 2011, to Jennifer Pilat, the Manufacturing Council, Room 4043...: Jennifer Pilat, the Manufacturing Council, Room 4043, 1401 Constitution Avenue, NW., Washington, DC 20230...

A two-hop based adaptive routing protocol for real-time wireless sensor networks.

PubMed

Rachamalla, Sandhya; Kancherla, Anitha Sheela

2016-01-01

One of the most important and challenging issues in wireless sensor networks (WSNs) is to optimally manage the limited energy of nodes without degrading the routing efficiency. In this paper, we propose an energy-efficient adaptive routing mechanism for WSNs, which saves energy of nodes by removing the much delayed packets without degrading the real-time performance of the used routing protocol. It uses the adaptive transmission power algorithm which is based on the attenuation of the wireless link to improve the energy efficiency. The proposed routing mechanism can be associated with any geographic routing protocol and its performance is evaluated by integrating with the well known two-hop based real-time routing protocol, PATH and the resulting protocol is energy-efficient adaptive routing protocol (EE-ARP). The EE-ARP performs well in terms of energy consumption, deadline miss ratio, packet drop and end-to-end delay.

Country profile: Hungary

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

Not Available

1991-09-01

Country Profile: Hungary has been prepared as a background document for use by US Government agencies and US businesses interested in becoming involved with the new democracies of Eastern Europe as they pursue sustainable economic development. The focus of the Profile is on energy and highlights information on Hungary`s energy supply, demand, and utilization. It identifies patterns of energy usage in the important economic sectors, especially industry, and provides a preliminary assessment for opportunities to improve efficiencies in energy production, distribution and use by introducing more efficient technologies. The use of more efficient technologies would have the added benefit ofmore » reducing the environmental impact which, although is not the focus of the report, is an issue that effects energy choices. The Profile also presents considerable economic information, primarily in the context of how economic restructuring may affect energy supply, demand, and the introduction of more efficient technologies.« less

Country profile: Hungary

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

Not Available

1991-09-01

Country Profile: Hungary has been prepared as a background document for use by US Government agencies and US businesses interested in becoming involved with the new democracies of Eastern Europe as they pursue sustainable economic development. The focus of the Profile is on energy and highlights information on Hungary's energy supply, demand, and utilization. It identifies patterns of energy usage in the important economic sectors, especially industry, and provides a preliminary assessment for opportunities to improve efficiencies in energy production, distribution and use by introducing more efficient technologies. The use of more efficient technologies would have the added benefit ofmore » reducing the environmental impact which, although is not the focus of the report, is an issue that effects energy choices. The Profile also presents considerable economic information, primarily in the context of how economic restructuring may affect energy supply, demand, and the introduction of more efficient technologies.« less

US Clean Energy Sector and the Opportunity for Modeling and Simulation

NASA Technical Reports Server (NTRS)

Inge, Carole Cameron

2011-01-01

The following paper sets forth the current understanding of the US clean energy demand and opportunity. As clean energy systems come online and technology is developed, modeling and simulation of these complex energy programs provides an untapped business opportunity. The US Department of Defense provides a great venue for developing new technology in the energy sector because it is demanding lower fuel costs, more energy efficiencies in its buildings and bases, and overall improvements in its carbon footprint. These issues coupled with the security issues faced by foreign dependence on oil will soon bring more clean energy innovations to the forefront (lighter batteries for soldiers, alternative fuel for jets, energy storage systems for ships, etc).

National Aeronautics and Space Administration (NASA) Earth Science Research for Energy Management. Part 1; Overview of Energy Issues and an Assessment of the Potential for Application of NASA Earth Science Research

NASA Technical Reports Server (NTRS)

Zell, E.; Engel-Cox, J.

2005-01-01

Effective management of energy resources is critical for the U.S. economy, the environment, and, more broadly, for sustainable development and alleviating poverty worldwide. The scope of energy management is broad, ranging from energy production and end use to emissions monitoring and mitigation and long-term planning. Given the extensive NASA Earth science research on energy and related weather and climate-related parameters, and rapidly advancing energy technologies and applications, there is great potential for increased application of NASA Earth science research to selected energy management issues and decision support tools. The NASA Energy Management Program Element is already involved in a number of projects applying NASA Earth science research to energy management issues, with a focus on solar and wind renewable energy and developing interests in energy modeling, short-term load forecasting, energy efficient building design, and biomass production.

76 FR 76174 - Request for Information on the State of the Offshore Renewable Energy Industry-Auction Format...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-06

... DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management [Docket BOEM-2011-0095] Request for...) AGENCY: Bureau of Ocean Energy Management (BOEM), Interior. ACTION: Request for information. SUMMARY..., each designed to efficiently issue renewable energy leases to those who value them most and are best...

A Digital Game-Based Learning System for Energy Education: An Energy COnservation PET

ERIC Educational Resources Information Center

Yang, Jie Chi; Chien, Kun Huang; Liu, Tzu Chien

2012-01-01

Energy education has been conducted to equip learners with relevant energy conservation knowledge for many years. However, learners seldom put the knowledge into practice and even have few ideas about how to reduce energy consumption. To this end, there is a need to address this issue to improve the efficiency of energy education. One of the…

Importance of hard coal in electricity generation in Poland

NASA Astrophysics Data System (ADS)

Plewa, Franciszek; Strozik, Grzegorz

2017-11-01

Polish energy sector is facing a number of challenges, in particular as regards the reconstruction of production potential, diversification of energy sources, environmental issues, adequate fuels supplies and other. Mandatory implementation of Europe 2020 strategy in terms of “3x20” targets (20% reduction of greenhouse gases, 20% of energy from renewable sources, and 20% increase of efficiency in energy production) requires fast decision, which have to be coordinated with energetic safety issues, increasing demands for electric energy, and other factors. In Poland almost 80% of power is installed in coal fired power plants and energy from hard coals is relatively less expensive than from other sources, especially renewable. The most of renewable energy sources power plants are unable to generate power in amounts which can be competitive with coal fires power stations and are highly expensive, what leads o high prices of electric energy. Alternatively, new generation of coal fired coal power plants is able to significantly increase efficiency, reduce carbon dioxide emission, and generate less expensive electric power in amounts adequate to the demands of a country.

Electric Power: Contemporary Issues and the Federal Role in Oversight and Regulation.

DTIC Science & Technology

1981-12-21

Regulatory Commission NRECA National Rural Electric Cooperative Asso- ciation PURPA Public Utility Regulatory Policies Act of 1978 REA Rural...energy efficiency standards for certain products and processes, and sets standards for solar energy and conservation in Federal buildings. PURPA --the...conservation, efficient use of facilities and resources, and equitable rates to electric consumers. PURPA also (1) encourages the use of cogeneration and

FUTURE OF ENERGY

EPA Science Inventory

A complete Scientific American issue of nine specialist articles was devoted to the concern of powering the global economy and addressing the effects of global warming. Control of atmospheric carbon, transportation fuel, efficient use of energy, the disposition of coal, opportuni...

Energy efficiency analysis of the manipulation process by the industrial objects with the use of Bernoulli gripping devices

NASA Astrophysics Data System (ADS)

Savkiv, Volodymyr; Mykhailyshyn, Roman; Duchon, Frantisek; Mikhalishin, Mykhailo

2017-11-01

The article deals with the topical issue of reducing energy consumption for transportation of industrial objects. The energy efficiency of the process of objects manipulation with the use of the orientation optimization method while gripping with the help of different methods has been studied. The analysis of the influence of the constituent parts of inertial forces, that affect the object of manipulation, on the necessary force characteristics and energy consumption of Bernoulli gripping device has been proposed. The economic efficiency of the use of the optimal orientation of Bernoulli gripping device while transporting the object of manipulation in comparison to the transportation without re-orientation has been proved.

Environmental Lessons from China: Finding Promising Policies 
in Unlikely Places

PubMed Central

Zhang, Junfeng

2011-01-01

Background: Alongside the major health risks posed by environmental pollution in China are recent achievements on several environmental issues that have affluent Western nations racing to catch up. The country has propelled itself to a position of leadership in clean energy and efficiency, for instance, with important consequences for public health. Objectives: We comment on China’s challenges and recent accomplishments in addressing environmental problems from domestic pollution to global climate change. We compare China’s commitment to clean energy technology with that of other leading nations and discuss key achievements in other areas, including vehicle efficiency standards and transportation policy. Discussion: We discuss policy directions that would secure much-needed improvements to environmental quality and health in China, along with actions that could motivate global action on issues of energy conservation and pollution reduction. Conclusions: A comprehensive regulatory and institutional framework for environmental policy is within reach in China but will require addressing major hurdles such as the lack of an independent monitoring mechanism and the need for greater transparency and enforcement in environmental matters. Meanwhile, China can continue to set important examples by investing in renewable energy, improving energy efficiency, and limiting greenhouse gas emissions. PMID:21402514

Solving employment problems in the European Union: The role of energy efficiency

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

Wiltshire, V.

1998-07-01

This paper is based on a project funded under the European Commission's SAVE (Specific Actions for Vigorous Energy Efficiency) program. The project is looking at the employment implications of energy efficiency programs, using a large number of case studies throughout the nine European Union (EU) countries participating in the project. Various modeling techniques are being used to investigate policy scenarios. The EU is particularly interested in looking at employment potential of energy efficiency at the present time. Traditionally, jobs in the environmental sector have only been seen as occurring in end-of-pipe type industries, such as pollution control; but a largemore » potential for employment opportunities has now been recognized in the energy efficiency sector. Included in the study will be a detailed discussion of the quality, as well as the quantity, of jobs created, i.e. what skill levels will be required and the types of people who would wish to undertake the work. The qualitative aspect of jobs will be looked at for their suitability for solving EU and country specific problems, such as long term unemployment of unskilled workers. This paper will present some initial results from the study and discuss the issues raised by it and by other recent work in this area. Such issues include not only the types and numbers of jobs directly created through the programs, but also indirect effects on the local, national and international economies. The negative effects, such as the reduced energy usage effect on the supply industry will also be examined.« less

78 FR 63823 - Energy Conservation Program: Test Procedures for Television Sets

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-25

... Conservation Program: Test Procedures for Television Sets AGENCY: Office of Energy Efficiency and Renewable... Energy (DOE) issued a notice of proposed rulemaking (NOPR) to establish a new test procedure for... additional testing and proposed amendments to the TV test procedure in its March 12, 2013 supplemental notice...

78 FR 4015 - Energy Conservation Program: Test Procedures for Microwave Ovens

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-18

... Conservation Program: Test Procedures for Microwave Ovens AGENCY: Office of Energy Efficiency and Renewable... Energy (DOE) issued a supplemental notice of proposed rulemaking (SNOPR) to amend the test procedures for microwave ovens. That SNOPR proposed amendments to the DOE test procedure to incorporate provisions from the...

Energy Efficiency Financing for Low- and Moderate-Income Households: Current State of the Market, Issues, and Opportunities

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

None

Although the need is great, many LMI households may not be able to afford efficiency improvements or may be inhibited from adopting efficiency for other reasons. Decision-makers across the country are currently exploring the challenges and potential solutions to ramping up adoption of efficiency in LMI households, including the use of financing.

75 FR 29338 - Energy Efficiency of Natural Gas Infrastructure and Operations Conference; Final Notice of Public...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-25

... recovery projects and issues associated with fugitive methane. Bruce Hedman, ICF International, on behalf... associated with fugitive methane. Richard D. Murphy, S.V.P. Energy Solutions Services, National Grid, on...

Women: Tapping a New Resource for Energy.

ERIC Educational Resources Information Center

Consumer Action Now, New York, NY.

In 1973 the Arab oil embargo triggered what has come to be known as the "energy crisis." In 1974, Consumer Action Now (CAN) decided to devote its full efforts to the grave issues of energy and to look for options that would preserve our choices as a new energy era is entered. Any transition to a more energy-efficient society depends on a…

Novel Material Integration for Reliable and Energy-Efficient NEM Relay Technology

NASA Astrophysics Data System (ADS)

Chen, I.-Ru

Energy-efficient switching devices have become ever more important with the emergence of ubiquitous computing. NEM relays are promising to complement CMOS transistors as circuit building blocks for future ultra-low-power information processing, and as such have recently attracted significant attention from the semiconductor industry and researchers. Relay technology potentially can overcome the energy efficiency limit for conventional CMOS technology due to several key characteristics, including zero OFF-state leakage, abrupt switching behavior, and potentially very low active energy consumption. However, two key issues must be addressed for relay technology to reach its full potential: surface oxide formation at the contacting surfaces leading to increased ON-state resistance after switching, and high switching voltages due to strain gradient present within the relay structure. This dissertation advances NEM relay technology by investigating solutions to both of these pressing issues. Ruthenium, whose native oxide is conductive, is proposed as the contacting material to improve relay ON-state resistance stability. Ruthenium-contact relays are fabricated after overcoming several process integration challenges, and show superior ON-state resistance stability in electrical measurements and extended device lifetime. The relay structural film is optimized via stress matching among all layers within the structure, to provide lower strain gradient (below 10E-3/microm -1) and hence lower switching voltage. These advancements in relay technology, along with the integration of a metallic interconnect layer, enable complex relay-based circuit demonstration. In addition to the experimental efforts, this dissertation theoretically analyzes the energy efficiency limit of a NEM switch, which is generally believed to be limited by the surface adhesion energy. New compact (<1 microm2 footprint), low-voltage (<0.1 V) switch designs are proposed to overcome this limit. The results pave a pathway to scaled energy-efficient electronic device technology.

Why do we need nuclear power? Energy policy in the light of history of civilization

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

Yoda, Susumu

1996-06-01

With the population explosion as a background, economic growth needs massive consumption of energy and resources. This massive consumption of energy and resources will deteriorate the global environment. It is a complicated chain of causes and effects. The problems of economic growth, resources and energy, and environment must be solved at the same time. Here the so-called ``Trilemma`` problem emerges. To overcome the Trilemma and assure a sustainable development of the whole world, approaches and actions are needed from various viewpoints including technology, socio-economic system and civilization. From the viewpoint of energy, it will be necessary to introduce all energymore » technologies which will not deteriorate the global environment. Energy conservation and efficiency are an important part of this process. It is also important to introduce renewable energy as much as possible. Even with these efforts, the energy needed by mankind in the 21st century will be tremendous. An energy source is needed which is adequate in terms of quantity, price, and environment. It is nuclear energy that meets these requirements. Several problems must be solved before the fundamental important merit of nuclear power can be realized. These issues are discussed here. They are divided into the following categories: economic issues; technical issues; social issues; political issues; and the issues in Asia.« less

Hydrothermal Synthesis of VO2 Polymorphs: Advantages, Challenges and Prospects for the Application of Energy Efficient Smart Windows.

PubMed

Li, Ming; Magdassi, Shlomo; Gao, Yanfeng; Long, Yi

2017-09-01

Vanadium dioxide (VO 2 ) is a widely studied inorganic phase change material, which has a reversible phase transition from semiconducting monoclinic to metallic rutile phase at a critical temperature of τ c ≈ 68 °C. The abrupt decrease of infrared transmittance in the metallic phase makes VO 2 a potential candidate for thermochromic energy efficient windows to cut down building energy consumption. However, there are three long-standing issues that hindered its application in energy efficient windows: high τ c , low luminous transmittance (T lum ), and undesirable solar modulation ability (ΔT sol ). Many approaches, including nano-thermochromism, porous films, biomimetic surface reconstruction, gridded structures, antireflective overcoatings, etc, have been proposed to tackle these issues. The first approach-nano-thermochromism-which is to integrate VO 2 nanoparticles in a transparent matrix, outperforms the rest; while the thermochromic performance is determined by particle size, stoichiometry, and crystallinity. A hydrothermal method is the most common method to fabricate high-quality VO 2 nanoparticles, and has its own advantages of large-scale synthesis and precise phase control of VO 2 . This Review focuses on hydrothermal synthesis, physical properties of VO 2 polymorphs, and their transformation to thermochromic VO 2 (M), and discusses the advantages, challenges, and prospects of VO 2 (M) in energy-efficient smart windows application. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Efficient and equitable spatial allocation of renewable power plants at the country scale

NASA Astrophysics Data System (ADS)

Drechsler, Martin; Egerer, Jonas; Lange, Martin; Masurowski, Frank; Meyerhoff, Jürgen; Oehlmann, Malte

2017-09-01

Globally, the production of renewable energy is undergoing rapid growth. One of the most pressing issues is the appropriate allocation of renewable power plants, as the question of where to produce renewable electricity is highly controversial. Here we explore this issue through analysis of the efficient and equitable spatial allocation of wind turbines and photovoltaic power plants in Germany. We combine multiple methods, including legal analysis, economic and energy modelling, monetary valuation and numerical optimization. We find that minimum distances between renewable power plants and human settlements should be as small as is legally possible. Even small reductions in efficiency lead to large increases in equity. By considering electricity grid expansion costs, we find a more even allocation of power plants across the country than is the case when grid expansion costs are neglected.

EDIN-USVI Clean Energy Quarterly: Volume 1, Issue 3, September 2011 (Newsletter)

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

Not Available

2011-09-01

This quarterly newsletter provides timely news and information about the plans and progress of the Energy Development in Island Nations-U.S. Virgin Islands pilot project, including significant events and milestones, work undertaken by each of the five working groups, and project-related renewable energy and energy efficiency educational outreach and technology deployment efforts.

Modeling and Simulation of HVAC Faulty Operations and Performance Degradation due to Maintenance Issues

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

Wang, Liping; Hong, Tianzhen

Almost half of the total energy used in the U.S. buildings is consumed by heating, ventilation and air conditionings (HVAC) according to EIA statistics. Among various driving factors to energy performance of building, operations and maintenance play a significant role. Many researches have been done to look at design efficiencies and operational controls for improving energy performance of buildings, but very few study the impacts of HVAC systems maintenance. Different practices of HVAC system maintenance can result in substantial differences in building energy use. If a piece of HVAC equipment is not well maintained, its performance will degrade. If sensorsmore » used for control purpose are not calibrated, not only building energy usage could be dramatically increased, but also mechanical systems may not be able to satisfy indoor thermal comfort. Properly maintained HVAC systems can operate efficiently, improve occupant comfort, and prolong equipment service life. In the paper, maintenance practices for HVAC systems are presented based on literature reviews and discussions with HVAC engineers, building operators, facility managers, and commissioning agents. We categorize the maintenance practices into three levels depending on the maintenance effort and coverage: 1) proactive, performance-monitored maintenance; 2) preventive, scheduled maintenance; and 3) reactive, unplanned or no maintenance. A sampled list of maintenance issues, including cooling tower fouling, boiler/chiller fouling, refrigerant over or under charge, temperature sensor offset, outdoor air damper leakage, outdoor air screen blockage, outdoor air damper stuck at fully open position, and dirty filters are investigated in this study using field survey data and detailed simulation models. The energy impacts of both individual maintenance issue and combined scenarios for an office building with central VAV systems and central plant were evaluated by EnergyPlus simulations using three approaches: 1) direct modeling with EnergyPlus, 2) using the energy management system feature of EnergyPlus, and 3) modifying EnergyPlus source code. The results demonstrated the importance of maintenance for HVAC systems on energy performance of buildings. The research is intended to provide a guideline to help practitioners and building operators to gain the knowledge of maintaining HVAC systems in efficient operations, and prioritize HVAC maintenance work plan. The paper also discusses challenges of modeling building maintenance issues using energy simulation programs.« less

Energy minimization strategies and renewable energy utilization for desalination: a review.

PubMed

Subramani, Arun; Badruzzaman, Mohammad; Oppenheimer, Joan; Jacangelo, Joseph G

2011-02-01

Energy is a significant cost in the economics of desalinating waters, but water scarcity is driving the rapid expansion in global installed capacity of desalination facilities. Conventional fossil fuels have been utilized as their main energy source, but recent concerns over greenhouse gas (GHG) emissions have promoted global development and implementation of energy minimization strategies and cleaner energy supplies. In this paper, a comprehensive review of energy minimization strategies for membrane-based desalination processes and utilization of lower GHG emission renewable energy resources is presented. The review covers the utilization of energy efficient design, high efficiency pumping, energy recovery devices, advanced membrane materials (nanocomposite, nanotube, and biomimetic), innovative technologies (forward osmosis, ion concentration polarization, and capacitive deionization), and renewable energy resources (solar, wind, and geothermal). Utilization of energy efficient design combined with high efficiency pumping and energy recovery devices have proven effective in full-scale applications. Integration of advanced membrane materials and innovative technologies for desalination show promise but lack long-term operational data. Implementation of renewable energy resources depends upon geography-specific abundance, a feasible means of handling renewable energy power intermittency, and solving technological and economic scale-up and permitting issues. Copyright © 2011 Elsevier Ltd. All rights reserved.

[Environment and energy in hospitals: assessment of usage and impact of Health Facilities in the Lombardy Region].

PubMed

Brioschi, A; Capolongo, S; Buffoli, M

2010-01-01

The research moves from the current global and local context and from shared development strategies. From the observation and the analysis of contemporary environmental and energy issues and redefined directions of growth of human activity, it is addressing the question of environmental sustainability and energy conservation of building hospital systems. The work has developed a field survey relating the specific topic of energy saving and efficiency of the Park Hospital in the Italian Lombardy Region. This has been articulated in a diagnosis of technology and efficiency of regional hospitals, implemented through a census, and in a subsequent identification of interventional cases, in order to show its economic, environmental and health performance of the energy efficiency consumption and the environmentally sound.

Energy efficiency evaluation of tree-topology 10 gigabit ethernet passive optical network and ring-topology time- and wavelength-division-multiplexed passive optical network

NASA Astrophysics Data System (ADS)

Song, Jingjing; Yang, Chuanchuan; Zhang, Qingxiang; Ma, Zhuang; Huang, Xingang; Geng, Dan; Wang, Ziyu

2015-09-01

Higher capacity and larger scales have always been the top targets for the evolution of optical access networks, driven by the ever-increasing demand from the end users. One thing that started to attract wide attention not long ago, but with at least equal importance as capacity and scale, is energy efficiency, a metric essential nowadays as human beings are confronted with severe environmental issues like global warming, air pollution, and so on. Here, different from the conventional energy consumption analysis of tree-topology networks, we propose an effective energy consumption calculation method to compare the energy efficiency of the tree-topology 10 gigabit ethernet passive optical network (10G-EPON) and ring-topology time- and wavelength-division-multiplexed passive optical network (TWDM-PON), two experimental networks deployed in China. Numerical results show that the ring-topology TWDM-PON networks with 2, 4, 8, and 16 wavelengths are more energy efficient than the tree-topology 10G-EPON, although 10G-EPON consumes less energy. Also, TWDM-PON with four wavelengths is the most energy-efficient network candidate and saves 58.7% more energy than 10G-EPON when fully loaded.

Electrospinning of Nanofibers for Energy Applications

PubMed Central

Sun, Guiru; Sun, Liqun; Xie, Haiming; Liu, Jia

2016-01-01

With global concerns about the shortage of fossil fuels and environmental issues, the development of efficient and clean energy storage devices has been drastically accelerated. Nanofibers are used widely for energy storage devices due to their high surface areas and porosities. Electrospinning is a versatile and efficient fabrication method for nanofibers. In this review, we mainly focus on the application of electrospun nanofibers on energy storage, such as lithium batteries, fuel cells, dye-sensitized solar cells and supercapacitors. The structure and properties of nanofibers are also summarized systematically. The special morphology of nanofibers prepared by electrospinning is significant to the functional materials for energy storage. PMID:28335256

Modeling Energy Efficiency As A Green Logistics Component In Vehicle Assembly Line

NASA Astrophysics Data System (ADS)

Oumer, Abduaziz; Mekbib Atnaw, Samson; Kie Cheng, Jack; Singh, Lakveer

2016-11-01

This paper uses System Dynamics (SD) simulation to investigate the concept green logistics in terms of energy efficiency in automotive industry. The car manufacturing industry is considered to be one of the highest energy consuming industries. An efficient decision making model is proposed that capture the impacts of strategic decisions on energy consumption and environmental sustainability. The sources of energy considered in this research are electricity and fuel; which are the two main types of energy sources used in a typical vehicle assembly plant. The model depicts the performance measurement for process- specific energy measures of painting, welding, and assembling processes. SD is the chosen simulation method and the main green logistics issues considered are Carbon Dioxide (CO2) emission and energy utilization. The model will assist decision makers acquire an in-depth understanding of relationship between high level planning and low level operation activities on production, environmental impacts and costs associated. The results of the SD model signify the existence of positive trade-offs between green practices of energy efficiency and the reduction of CO2 emission.

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

Mittal, Sparsh; Zhang, Zhao

With each CMOS technology generation, leakage energy consumption has been dramatically increasing and hence, managing leakage power consumption of large last-level caches (LLCs) has become a critical issue in modern processor design. In this paper, we present EnCache, a novel software-based technique which uses dynamic profiling-based cache reconfiguration for saving cache leakage energy. EnCache uses a simple hardware component called profiling cache, which dynamically predicts energy efficiency of an application for 32 possible cache configurations. Using these estimates, system software reconfigures the cache to the most energy efficient configuration. EnCache uses dynamic cache reconfiguration and hence, it does not requiremore » offline profiling or tuning the parameter for each application. Furthermore, EnCache optimizes directly for the overall memory subsystem (LLC and main memory) energy efficiency instead of the LLC energy efficiency alone. The experiments performed with an x86-64 simulator and workloads from SPEC2006 suite confirm that EnCache provides larger energy saving than a conventional energy saving scheme. For single core and dual-core system configurations, the average savings in memory subsystem energy over a shared baseline configuration are 30.0% and 27.3%, respectively.« less

How effective is mandatory building energy disclosure program in Australia?

NASA Astrophysics Data System (ADS)

Kim, S.; Lim, B. T. H.

2018-04-01

Mandatory green building regulations are often considered as the most effective tool to promote better energy efficiency and environmental protection. Nevertheless, its effectiveness compared to the voluntary counterpart has not been fully explored yet. In addressing this gap, this study aims to examine the environmental performance of green building stocks affected by the Australian mandatory building energy disclosure program. To this, this study analysed energy savings and carbon reduction efficiencies using the normalisation approach. The result shows that mandatory energy disclosure program did contribute to the reduction in energy usage and carbon emissions from the affected building stocks. More specifically, affected green building stocks showed a good efficiency especially in carbon reductions. The research results inform policymakers the possible improvement required for the mandatory disclosure program to increase the effectiveness towards dealing with the contemporary environmental issues aroused from the building sector, especially in energy savings perspective.

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

Mundaca, Luis; Neij, Lena; Worrell, Ernst

The growing complexities of energy systems, environmental problems and technology markets are driving and testing most energy-economy models to their limits. To further advance bottom-up models from a multidisciplinary energy efficiency policy evaluation perspective, we review and critically analyse bottom-up energy-economy models and corresponding evaluation studies on energy efficiency policies to induce technological change. We use the household sector as a case study. Our analysis focuses on decision frameworks for technology choice, type of evaluation being carried out, treatment of market and behavioural failures, evaluated policy instruments, and key determinants used to mimic policy instruments. Although the review confirms criticismmore » related to energy-economy models (e.g. unrealistic representation of decision-making by consumers when choosing technologies), they provide valuable guidance for policy evaluation related to energy efficiency. Different areas to further advance models remain open, particularly related to modelling issues, techno-economic and environmental aspects, behavioural determinants, and policy considerations.« less

Woody biomass pretreatment for cellulosic ethanol production : technology and energy consumption evaluation

Treesearch

Junyong Zhu; X.J. Pan

2010-01-01

This review presents a comprehensive discussion of the key technical issues in woody biomass pretreatment: barriers to efficient cellulose saccharification, pretreatment energy consumption, in particular energy consumed for wood-size reduction, and criteria to evaluate the performance of a pretreatment. A post-chemical pretreatment size-reduction approach is proposed...

Changes in the Cost of Energy in One State's School Districts. Issues & Answers. REL 2010-No. 088

ERIC Educational Resources Information Center

Cymrot, Donald J.; Martinez, Miguel; Jones, Joseph F.

2010-01-01

To support the work of Tennessee's Energy Efficient Schools Initiative (EESI) Council, this report describes data on energy expenditures in school districts for 2002/03-2007/08. Energy expenditures rose from about 2.6 percent to about 3.0 percent of total expenditures over the period, with some differences in the mix of energy types and…

Energy harvesting for the implantable biomedical devices: issues and challenges.

PubMed

Hannan, Mahammad A; Mutashar, Saad; Samad, Salina A; Hussain, Aini

2014-06-20

The development of implanted devices is essential because of their direct effect on the lives and safety of humanity. This paper presents the current issues and challenges related to all methods used to harvest energy for implantable biomedical devices. The advantages, disadvantages, and future trends of each method are discussed. The concept of harvesting energy from environmental sources and human body motion for implantable devices has gained a new relevance. In this review, the harvesting kinetic, electromagnetic, thermal and infrared radiant energies are discussed. Current issues and challenges related to the typical applications of these methods for energy harvesting are illustrated. Suggestions and discussion of the progress of research on implantable devices are also provided. This review is expected to increase research efforts to develop the battery-less implantable devices with reduced over hole size, low power, high efficiency, high data rate, and improved reliability and feasibility. Based on current literature, we believe that the inductive coupling link is the suitable method to be used to power the battery-less devices. Therefore, in this study, the power efficiency of the inductive coupling method is validated by MATLAB based on suggested values. By further researching and improvements, in the future the implantable and portable medical devices are expected to be free of batteries.

Comparative Evaluation of Financing Programs: Insights From California’s Experience

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

Deason, Jeff

Berkeley Lab examines criteria for a comparative assessment of multiple financing programs for energy efficiency, developed through a statewide public process in California. The state legislature directed the California Alternative Energy and Advanced Transportation Financing Authority (CAEATFA) to develop these criteria. CAEATFA's report to the legislature, an invaluable reference for other jurisdictions considering these topics, discusses the proposed criteria and the rationales behind them in detail. Berkeley Lab's brief focuses on several salient issues that emerged during the criteria development and discussion process. Many of these issues are likely to arise in other states that plan to evaluate the impactsmore » of energy efficiency financing programs, whether for a single program or multiple programs. Issues discussed in the brief include: -The stakeholder process to develop the proposed assessment criteria -Attribution of outcomes - such as energy savings - to financing programs vs. other drivers -Choosing the outcome metric of primary interest: program take-up levels vs. savings -The use of net benefits vs. benefit-cost ratios for cost-effectiveness evaluation -Non-energy factors -Consumer protection factors -Market transformation impacts -Accommodating varying program goals in a multi-program evaluation -Accounting for costs and risks borne by various parties, including taxpayers and utility customers, in cost-effectiveness analysis -How to account for potential synergies among programs in a multi-program evaluation« less

Energy harvesting for the implantable biomedical devices: issues and challenges

PubMed Central

2014-01-01

The development of implanted devices is essential because of their direct effect on the lives and safety of humanity. This paper presents the current issues and challenges related to all methods used to harvest energy for implantable biomedical devices. The advantages, disadvantages, and future trends of each method are discussed. The concept of harvesting energy from environmental sources and human body motion for implantable devices has gained a new relevance. In this review, the harvesting kinetic, electromagnetic, thermal and infrared radiant energies are discussed. Current issues and challenges related to the typical applications of these methods for energy harvesting are illustrated. Suggestions and discussion of the progress of research on implantable devices are also provided. This review is expected to increase research efforts to develop the battery-less implantable devices with reduced over hole size, low power, high efficiency, high data rate, and improved reliability and feasibility. Based on current literature, we believe that the inductive coupling link is the suitable method to be used to power the battery-less devices. Therefore, in this study, the power efficiency of the inductive coupling method is validated by MATLAB based on suggested values. By further researching and improvements, in the future the implantable and portable medical devices are expected to be free of batteries. PMID:24950601

Energy Performance Techniques and Technologies: Preserving Historic Homes – Volume 13

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

Pacific Northwest National Laboratory

2011-02-01

Following Building America-sponsored research, this guide focuses on planning energy-efficient improvements for historic houses while preserving the home’s historic features, being aware of and adhering to regulations related to historic designations, and addressing health and safety issues.

Photocatalytic Cellulosic Electrospun Fibers for the Degradation of Potent Cyanobacteria Toxin Microcystin-LR

DTIC Science & Technology

2012-01-01

treatment applications using solar light as a renewable source of energy. Introduction The need for low cost and efficient water treatment strategies... photocatalysis with nanoparticles (such as titania, TiO2) show tremendous promise as a simple and energy efficient tech- nology for water purification and...which limits the amount of available sunlight that can be used for photocatalysis . To circumvent this issue, methods have been developed to extend

Regional issues in energy development: a dialogue of east and west

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

Leman, C.K.

1981-01-01

Topics presented at the symposium include: comparing Canadian and US regional energy conflicts, beyond greed and envy; summary of energy impacts on resource-rich and resource-poor regions; equity and efficiency in regional energy policy; technical solutions to political problems; political solutions to political problems; and a summary, pulling apart or getting together, an assessment of the dialogue. (GHT)

Exergetic analysis of autonomous power complex for drilling rig

NASA Astrophysics Data System (ADS)

Lebedev, V. A.; Karabuta, V. S.

2017-10-01

The article considers the issue of increasing the energy efficiency of power equipment of the drilling rig. At present diverse types of power plants are used in power supply systems. When designing and choosing a power plant, one of the main criteria is its energy efficiency. The main indicator in this case is the effective efficiency factor calculated by the method of thermal balances. In the article, it is suggested to use the exergy method to determine energy efficiency, which allows to perform estimations of the thermodynamic perfection degree of the system by the example of a gas turbine plant: relative estimation (exergetic efficiency factor) and an absolute estimation. An exergetic analysis of the gas turbine plant operating in a simple scheme was carried out using the program WaterSteamPro. Exergy losses in equipment elements are calculated.

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.

Nanomaterials for renewable energy

DOE PAGES

Chen, Shimou; Li, Liang; Sun, Hanwen; ...

2015-05-19

With demand for sustainable energy, resource, and environment protection, new material technologies are constantly expanding during the last few couple of decades. An intensive attention has been given by the scientific communities. In particular, nanomaterials are increasingly playing an active role either by increasing the efficiency of the energy storage and conversion processes or by improving the device design and performance. This special issue presents recent research advances in various aspects of energy storage technologies, advanced batteries, fuel cells, solar cell, biofuels, and so on. Design and synthesis of novel materials have demonstrated great impact on the utilization of themore » sustainable energy, which need to solve the increasing shortage of resource and the issues of environmental pollution.« less

International Symposium on Clusters and Nanostructures (Energy, Environment, and Health)

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

Jena, Puru

The international Symposium on Clusters and Nanostructures was held in Richmond, Virginia during November 7-10, 2011. The symposium focused on the roles clusters and nanostructures play in solving outstanding problems in clean and sustainable energy, environment, and health; three of the most important issues facing science and society. Many of the materials issues in renewable energies, environmental impacts of energy technologies as well as beneficial and toxicity issues of nanoparticles in health are intertwined. Realizing that both fundamental and applied materials issues require a multidisciplinary approach the symposium provided a forum by bringing researchers from physics, chemistry, materials science, andmore » engineering fields to share their ideas and results, identify outstanding problems, and develop new collaborations. Clean and sustainable energy sessions addressed challenges in production, storage, conversion, and efficiency of renewable energies such as solar, wind, bio, thermo-electric, and hydrogen. Environmental issues dealt with air- and water-pollution and conservation, environmental remediation and hydrocarbon processing. Topics in health included therapeutic and diagnostic methods as well as health hazards attributed to nanoparticles. Cross-cutting topics such as reactions, catalysis, electronic, optical, and magnetic properties were also covered.« less

Improving urban district heating systems and assessing the efficiency of the energy usage therein

NASA Astrophysics Data System (ADS)

Orlov, M. E.; Sharapov, V. I.

2017-11-01

The report describes issues in connection with improving urban district heating systems from combined heat power plants (CHPs), to propose the ways for improving the reliability and the efficiency of the energy usage (often referred to as “energy efficiency”) in such systems. The main direction of such urban district heating systems improvement suggests transition to combined heating systems that include structural elements of both centralized and decentralized systems. Such systems provide the basic part of thermal power via highly efficient methods for extracting thermal power plants turbines steam, while peak loads are covered by decentralized peak thermal power sources to be mounted at consumers’ locations, with the peak sources being also reserve thermal power sources. The methodology was developed for assessing energy efficiency of the combined district heating systems, implemented as a computer software product capable of comparatively calculating saving on reference fuel for the system.

MDA Establishes Effective Metrics for Energy Reduction and Other Environmental Performance Improvements

DTIC Science & Technology

2009-05-06

More Efficient Fuel, Electricity & Water Use (Cont’d.)  Energy and resource conservation campaign: beginning to implement an energy and resource...articles about energy conservation awareness and soliciting employee ideas  Reducing water temperature at MDIOC came from someone reporting the...issue after reading about conservation tips in the newsletter 12 Fuel, Electricity & Water Use Metrics  MDA’s objective is energy use reduction of 3

Integrating Variable Renewable Energy into the Grid: Key Issues, Greening the Grid (Spanish Version)

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

This is the Spanish version of 'Greening the Grid - Integrating Variable Renewable Energy into the Grid: Key Issues'. To foster sustainable, low-emission development, many countries are establishing ambitious renewable energy targets for their electricity supply. Because solar and wind tend to be more variable and uncertain than conventional sources, meeting these targets will involve changes to power system planning and operations. Grid integration is the practice of developing efficient ways to deliver variable renewable energy (VRE) to the grid. Good integration methods maximize the cost-effectiveness of incorporating VRE into the power system while maintaining or increasing system stability andmore » reliability. When considering grid integration, policy makers, regulators, and system operators consider a variety of issues, which can be organized into four broad topics: New Renewable Energy Generation, New Transmission, Increased System Flexibility, and Planning for a High RE Future.« less

Material efficiency: providing material services with less material production

PubMed Central

Allwood, Julian M.; Ashby, Michael F.; Gutowski, Timothy G.; Worrell, Ernst

2013-01-01

Material efficiency, as discussed in this Meeting Issue, entails the pursuit of the technical strategies, business models, consumer preferences and policy instruments that would lead to a substantial reduction in the production of high-volume energy-intensive materials required to deliver human well-being. This paper, which introduces a Discussion Meeting Issue on the topic of material efficiency, aims to give an overview of current thinking on the topic, spanning environmental, engineering, economics, sociology and policy issues. The motivations for material efficiency include reducing energy demand, reducing the emissions and other environmental impacts of industry, and increasing national resource security. There are many technical strategies that might bring it about, and these could mainly be implemented today if preferred by customers or producers. However, current economic structures favour the substitution of material for labour, and consumer preferences for material consumption appear to continue even beyond the point at which increased consumption provides any increase in well-being. Therefore, policy will be required to stimulate material efficiency. A theoretically ideal policy measure, such as a carbon price, would internalize the externality of emissions associated with material production, and thus motivate change directly. However, implementation of such a measure has proved elusive, and instead the adjustment of existing government purchasing policies or existing regulations— for instance to do with building design, planning or vehicle standards—is likely to have a more immediate effect. PMID:23359746

Material efficiency: providing material services with less material production.

PubMed

Allwood, Julian M; Ashby, Michael F; Gutowski, Timothy G; Worrell, Ernst

2013-03-13

Material efficiency, as discussed in this Meeting Issue, entails the pursuit of the technical strategies, business models, consumer preferences and policy instruments that would lead to a substantial reduction in the production of high-volume energy-intensive materials required to deliver human well-being. This paper, which introduces a Discussion Meeting Issue on the topic of material efficiency, aims to give an overview of current thinking on the topic, spanning environmental, engineering, economics, sociology and policy issues. The motivations for material efficiency include reducing energy demand, reducing the emissions and other environmental impacts of industry, and increasing national resource security. There are many technical strategies that might bring it about, and these could mainly be implemented today if preferred by customers or producers. However, current economic structures favour the substitution of material for labour, and consumer preferences for material consumption appear to continue even beyond the point at which increased consumption provides any increase in well-being. Therefore, policy will be required to stimulate material efficiency. A theoretically ideal policy measure, such as a carbon price, would internalize the externality of emissions associated with material production, and thus motivate change directly. However, implementation of such a measure has proved elusive, and instead the adjustment of existing government purchasing policies or existing regulations-- for instance to do with building design, planning or vehicle standards--is likely to have a more immediate effect.

76 FR 49279 - Energy Efficiency Design Standards for New Federal Commercial and Multi-Family High-Rise...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-10

... Management. The life-cycle cost guidance and required discount rates and energy price projections are... Supplement to The National Institute of Standards and Technology Handbook 135: ``Energy Price Indices and...;Prices of new books are listed in the first FEDERAL REGISTER issue of each #0;week. #0; #0; #0; #0;#0...

FOREWORD: Focus on Advanced Ceramics Focus on Advanced Ceramics

NASA Astrophysics Data System (ADS)

Ohashi, Naoki

2011-06-01

Much research has been devoted recently to developing technologies for renewable energy and improving the efficiency of the processes and devices used in industry and everyday life. Efficient solutions have been found using novel materials such as platinum and palladium-based catalysts for car exhaust systems, samarium-cobalt and neodymium-iron-boron permanent magnets for electrical motors, and so on. However, their realization has resulted in an increasing demand for rare elements and in their deficit, the development of new materials based on more abundant elements and new functionalities of traditional materials. Moreover, increasing environmental and health concerns demand substitution of toxic or hazardous substances with nature-friendly alternatives. In this context, this focus issue on advanced ceramics aims to review current trends in ceramics science and technology. It is related to the International Conference on Science and Technology of Advanced Ceramics (STAC) held annually to discuss the emerging issues in the field of ceramics. An important direction of ceramic science is the collaboration between experimental and theoretical sciences. Recent developments in density functional theory and computer technology have enabled the prediction of physical and chemical properties of ceramics, thereby assisting the design of new materials. Therefore, this focus issue includes articles devoted to theory and advanced characterization techniques. As mentioned above, the potential shortage of rare elements is becoming critical to the industry and has resulted in a Japanese government initiative called the 'Ubiquitous Element Strategy'. This focus issue also includes articles related to this strategy and to the associated topics of energy conversion, such as phosphors for high-efficiency lighting and photocatalysts for solar-energy harvesting. We hope that this focus issue will provide a timely overview of current trends and problems in ceramics science and technology and promote new research and development in this field.

A Survey on Energy Conserving Mechanisms for the Internet of Things: Wireless Networking Aspects.

PubMed

Abbas, Zeeshan; Yoon, Wonyong

2015-09-25

The Internet of Things (IoT) is an emerging key technology for future industries and everyday lives of people, where a myriad of battery operated sensors, actuators, and smart objects are connected to the Internet to provide services such as mobile healthcare, intelligent transport system, environmental monitoring, etc. Since energy efficiency is of utmost importance to these battery constrained IoT devices, IoT-related standards and research works have focused on the device energy conserving issues. This paper presents a comprehensive survey on energy conserving issues and solutions in using diverse wireless radio access technologies for IoT connectivity, e.g., the 3rd Generation Partnership Project (3GPP) machine type communications, IEEE 802.11ah, Bluetooth Low Energy (BLE), and Z-Wave. We look into the literature in broad areas of standardization, academic research, and industry development, and structurally summarize the energy conserving solutions based on several technical criteria. We also propose future research directions regarding energy conserving issues in wireless networking-based IoT.

A Survey on Energy Conserving Mechanisms for the Internet of Things: Wireless Networking Aspects

PubMed Central

Abbas, Zeeshan; Yoon, Wonyong

2015-01-01

The Internet of Things (IoT) is an emerging key technology for future industries and everyday lives of people, where a myriad of battery operated sensors, actuators, and smart objects are connected to the Internet to provide services such as mobile healthcare, intelligent transport system, environmental monitoring, etc. Since energy efficiency is of utmost importance to these battery constrained IoT devices, IoT-related standards and research works have focused on the device energy conserving issues. This paper presents a comprehensive survey on energy conserving issues and solutions in using diverse wireless radio access technologies for IoT connectivity, e.g., the 3rd Generation Partnership Project (3GPP) machine type communications, IEEE 802.11ah, Bluetooth Low Energy (BLE), and Z-Wave. We look into the literature in broad areas of standardization, academic research, and industry development, and structurally summarize the energy conserving solutions based on several technical criteria. We also propose future research directions regarding energy conserving issues in wireless networking-based IoT. PMID:26404275

How far can the world get on energy efficiency alone

NASA Astrophysics Data System (ADS)

Katzman, Martin T.

A recent analysis suggests that by pursuing a path of energy efficiency, the industrial world can maintain and the developing world can achieve a high standard of living with little increase in primary energy consumption over the next 50 years. Moreover, this scenario can be achieved with a reduction of fossil fuel consumption. Three basic issues discussed at a workshop recently held at ORNL are presented to address this thesis. First, is this thesis plausible; to what extent can the scenario be achieved with currently or nearly available technology. Second, why can't a better job be done in reaching the potential; what are the barriers to the deeper penetration of energy-efficient technologies. Third, what policy and technological strategies are necessary to fulfill this scenario.

Service-Aware Clustering: An Energy-Efficient Model for the Internet-of-Things

PubMed Central

Bagula, Antoine; Abidoye, Ademola Philip; Zodi, Guy-Alain Lusilao

2015-01-01

Current generation wireless sensor routing algorithms and protocols have been designed based on a myopic routing approach, where the motes are assumed to have the same sensing and communication capabilities. Myopic routing is not a natural fit for the IoT, as it may lead to energy imbalance and subsequent short-lived sensor networks, routing the sensor readings over the most service-intensive sensor nodes, while leaving the least active nodes idle. This paper revisits the issue of energy efficiency in sensor networks to propose a clustering model where sensor devices’ service delivery is mapped into an energy awareness model, used to design a clustering algorithm that finds service-aware clustering (SAC) configurations in IoT settings. The performance evaluation reveals the relative energy efficiency of the proposed SAC algorithm compared to related routing algorithms in terms of energy consumption, the sensor nodes’ life span and its traffic engineering efficiency in terms of throughput and delay. These include the well-known low energy adaptive clustering hierarchy (LEACH) and LEACH-centralized (LEACH-C) algorithms, as well as the most recent algorithms, such as DECSA and MOCRN. PMID:26703619

Service-Aware Clustering: An Energy-Efficient Model for the Internet-of-Things.

PubMed

Bagula, Antoine; Abidoye, Ademola Philip; Zodi, Guy-Alain Lusilao

2015-12-23

Current generation wireless sensor routing algorithms and protocols have been designed based on a myopic routing approach, where the motes are assumed to have the same sensing and communication capabilities. Myopic routing is not a natural fit for the IoT, as it may lead to energy imbalance and subsequent short-lived sensor networks, routing the sensor readings over the most service-intensive sensor nodes, while leaving the least active nodes idle. This paper revisits the issue of energy efficiency in sensor networks to propose a clustering model where sensor devices' service delivery is mapped into an energy awareness model, used to design a clustering algorithm that finds service-aware clustering (SAC) configurations in IoT settings. The performance evaluation reveals the relative energy efficiency of the proposed SAC algorithm compared to related routing algorithms in terms of energy consumption, the sensor nodes' life span and its traffic engineering efficiency in terms of throughput and delay. These include the well-known low energy adaptive clustering hierarchy (LEACH) and LEACH-centralized (LEACH-C) algorithms, as well as the most recent algorithms, such as DECSA and MOCRN.

Mechanical power efficiency of modified turbine blades

NASA Astrophysics Data System (ADS)

Mahmud, Syahir; Sampebatu, Limbran; Kwang, Suendy Ciayadi

2017-01-01

Abstract-The problem of energy crisis has become one of the unsolved issues until today. Indonesia has a lot of non-conventional energy sources that does not utilized effectively yet. For that the available resources must utilized efficiently due to the energy crisis and the growing energy needs. Among the abundant resources of energy, one potential source of energy is hydroelectric energy. This research compares the mechanical power efficiency generated by the Darrieus turbine, Savonius turbine and the Darrieus-Savonius turbine. The comparation of the mechanical power amongst the three turbine starts from the measurement of the water flow rate, water temperature, turbine rotation and force on the shaft on each type of turbine. The comparison will show the mechanical power efficiency of each turbine to find the most efficient turbine that can work optimally. The results show that with 0.637m/s flow velocity and 44.827 Watt of water flow power, the Darrieus-Savonius turbine can generate power equal to 29.927 Watt and shaft force around by 17 N. The Darrieus-Savonius turbine provides around 66.76% efficiency betwen the three turbines; Darrieus turbine, Savonius turbine and the Darrieus-Savonius turbine. Overall, the Darrieus Savonius turbine has the ability to work optimally at the research location.

Distance-Based and Low Energy Adaptive Clustering Protocol for Wireless Sensor Networks

PubMed Central

Gani, Abdullah; Anisi, Mohammad Hossein; Ab Hamid, Siti Hafizah; Akhunzada, Adnan; Khan, Muhammad Khurram

2016-01-01

A wireless sensor network (WSN) comprises small sensor nodes with limited energy capabilities. The power constraints of WSNs necessitate efficient energy utilization to extend the overall network lifetime of these networks. We propose a distance-based and low-energy adaptive clustering (DISCPLN) protocol to streamline the green issue of efficient energy utilization in WSNs. We also enhance our proposed protocol into the multi-hop-DISCPLN protocol to increase the lifetime of the network in terms of high throughput with minimum delay time and packet loss. We also propose the mobile-DISCPLN protocol to maintain the stability of the network. The modelling and comparison of these protocols with their corresponding benchmarks exhibit promising results. PMID:27658194

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.

Eco Assist Techniques through Real-time Monitoring of BEV Energy Usage Efficiency

PubMed Central

Kim, Younsun; Lee, Ingeol; Kang, Sungho

2015-01-01

Energy efficiency enhancement has become an increasingly important issue for battery electric vehicles. Even if it can be improved in many ways, the driver’s driving pattern strongly influences the battery energy consumption of a vehicle. In this paper, eco assist techniques to simply implement an energy-efficient driving assistant system are introduced, including eco guide, eco control and eco monitoring methods. The eco guide is provided to control the vehicle speed and accelerator pedal stroke, and eco control is suggested to limit the output power of the battery. For eco monitoring, the eco indicator and eco report are suggested to teach eco-friendly driving habits. The vehicle test, which is done in four ways, consists of federal test procedure (FTP)-75, new european driving cycle (NEDC), city and highway cycles, and visual feedback with audible warnings is provided to attract the driver’s voluntary participation. The vehicle test result shows that the energy usage efficiency can be increased up to 19.41%. PMID:26121611

48 CFR 23.705 - Electronic products environmental assessment tool.

Code of Federal Regulations, 2010 CFR

2010-10-01

... REGULATION SOCIOECONOMIC PROGRAMS ENVIRONMENT, ENERGY AND WATER EFFICIENCY, RENEWABLE ENERGY TECHNOLOGIES... standard for personal computer products— (i) Was issued by the Institute of Electrical and Electronics.... 104-113, the “National Technology Transfer and Advancement Act of 1995”, (see 11.102(c)); (iii) Meets...

LIGHTING FOR READING: DESIGNING AN LED LUMINAIRE FOR HOMES AND OFFICES

EPA Science Inventory

Energy waste from traditional incandescent light bulbs was reduced by fluorescent lamps, but they pose a threat to the environment due to the mercury in each tube and disposal issues. Light emitting diodes (LEDs) provide superior energy efficiency, longer life, toxin-free comp...

48 CFR 23.704 - Electronic products environmental assessment tool.

Code of Federal Regulations, 2011 CFR

2011-10-01

... REGULATION SOCIOECONOMIC PROGRAMS ENVIRONMENT, ENERGY AND WATER EFFICIENCY, RENEWABLE ENERGY TECHNOLOGIES... standard for personal computer products— (i) Was issued by the Institute of Electrical and Electronics.... 104-113, the “National Technology Transfer and Advancement Act of 1995”, (see 11.102(c)); (iii) Meets...

48 CFR 23.704 - Electronic products environmental assessment tool.

Code of Federal Regulations, 2012 CFR

2012-10-01

... REGULATION SOCIOECONOMIC PROGRAMS ENVIRONMENT, ENERGY AND WATER EFFICIENCY, RENEWABLE ENERGY TECHNOLOGIES... standard for personal computer products— (i) Was issued by the Institute of Electrical and Electronics.... 104-113, the “National Technology Transfer and Advancement Act of 1995”, (see 11.102(c)); (iii) Meets...

Measurement and decomposition of energy efficiency of Northeast China-based on super efficiency DEA model and Malmquist index.

PubMed

Ma, Xiaojun; Liu, Yan; Wei, Xiaoxue; Li, Yifan; Zheng, Mengchen; Li, Yudong; Cheng, Chaochao; Wu, Yumei; Liu, Zhaonan; Yu, Yuanbo

2017-08-01

Nowadays, environment problem has become the international hot issue. Experts and scholars pay more and more attention to the energy efficiency. Unlike most studies, which analyze the changes of TFEE in inter-provincial or regional cities, TFEE is calculated with the ratio of target energy value and actual energy input based on data in cities of prefecture levels, which would be more accurate. Many researches regard TFP as TFEE to do analysis from the provincial perspective. This paper is intended to calculate more reliably by super efficiency DEA, observe the changes of TFEE, and analyze its relation with TFP, and it proves that TFP is not equal to TFEE. Additionally, the internal influences of the TFEE are obtained via the Malmquist index decomposition. The external influences of the TFFE are analyzed afterward based on the Tobit models. Analysis results demonstrate that Heilongjiang has the highest TFEE followed by Jilin, and Liaoning has the lowest TFEE. Eventually, some policy suggestions are proposed for the influences of energy efficiency and study results.

Efficiency of energy recovery from waste incineration, in the light of the new Waste Framework Directive.

PubMed

Grosso, Mario; Motta, Astrid; Rigamonti, Lucia

2010-07-01

This paper deals with a key issue related to municipal waste incineration, which is the efficiency of energy recovery. A strong driver for improving the energy performances of waste-to-energy plants is the recent Waste Framework Directive (Directive 2008/98/EC of the European Parliament and of the Council of 19 November 2008 on waste and repealing certain Directives), which allows high efficiency installations to benefit from a status of "recovery" rather than "disposal". The change in designation means a step up in the waste hierarchy, where the lowest level of priority is now restricted to landfilling and low efficiency wastes incineration. The so-called "R1 formula" reported in the Directive, which counts for both production of power and heat, is critically analyzed and correlated to the more scientific-based approach of exergy efficiency. The results obtained for waste-to-energy plants currently operating in Europe reveal some significant differences in their performance, mainly related to the average size and to the availability of a heat market (district heating). Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Fairness and dynamic pricing: comments

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

Hogan, William W.

2010-07-15

In ''The Ethics of Dynamic Pricing,'' Ahmad Faruqui lays out a case for improved efficiency in using dynamic prices for retail electricity tariffs and addresses various issues about the distributional effects of alternative pricing mechanisms. The principal contrast is between flat or nearly constant energy prices and time-varying prices that reflect more closely the marginal costs of energy and capacity. The related issues of fairness criteria, contracts, risk allocation, cost allocation, means testing, real-time pricing, and ethical policies of electricity market design also must be considered. (author)

Fusion energy for space missions in the 21st century: Executive summary

NASA Technical Reports Server (NTRS)

Schulze, Norman R.

1991-01-01

Future space missions were hypothesized and analyzed, and the energy source of their accomplishment investigated. The missions included manned Mars, scientific outposts to and robotic sample return missions from the outer planets and asteroids, as well as fly-by and rendezvous missions with the Oort Cloud and the nearest star, Alpha Centauri. Space system parametric requirements and operational features were established. The energy means for accomplishing missions where delta v requirements range from 90 km/sec to 30,000 km/sec (High Energy Space Mission) were investigated. The need to develop a power space of this magnitude is a key issue to address if the U.S. civil space program is to continue to advance as mandated by the National Space Policy. Potential energy options which could provide the propulsion and electrical power system and operational requirements were reviewed and evaluated. Fusion energy was considered to be the preferred option and was analyzed in depth. Candidate fusion fuels were evaluated based upon the energy output and neutron flux. Additionally, fusion energy can offer significant safety, environmental, economic, and operational advantages. Reactors exhibiting a highly efficient use of magnetic fields for space use while at the same time offering efficient coupling to an exhaust propellant or to a direct energy convertor for efficient electrical production were examined. Near term approaches were identified. A strategy that will produce fusion powered vehicles as part of the space transportation infrastructure was developed. Space program resources must be directed toward this issue as a matter of the top policy priority.

Certification and brand identity for energy efficiency in competitive energy services markets

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

Prindle, W.R.; Wiser, R.

Resource commitments for energy efficiency from electricity companies are disappearing rapidly as the regulated Integrated Resource Planning and Demand-Side Management paradigms that fostered them give way to competitive power markets in a restructuring electricity industry. While free-market advocates claim that energy efficiency needs will be taken care of by competitive energy service providers, there is no assurance that efficiency will compete effectively with the panoply of other energy-related (and non-energy-related) services that are beginning to appear in early market offerings. This paper reports the results of a feasibility study for a certification and brand identity program for energy efficiency gearedmore » to competitive power markets. Funded by the Energy Foundation, this study involved a survey and personal interviews with stakeholders, plus a workshop to further the discussion. Stakeholders include independent power marketers and energy service companies, utility affiliate power marketers and energy service companies, government agencies, trade associations, non-profit organizations, equipment manufacturers, and consultants. The paper summarizes the study's findings on such key issues as: Whether a brand identity concept has a critical mass of interest and support; how qualification and certification could work in such a program; how a brand identity could be positioned in the market; how an efficiency brand identity could co-brand with renewable power branding programs and other green marketing efforts; and the resources and components needed to make such a program work on a national scale.« less

SPS issues: The need to look ahead

NASA Technical Reports Server (NTRS)

Dybdal, K. K.

1980-01-01

The need for a systemic examination of SPS for the purpose of identifying potential problem areas and the issues related to those areas, is considered. The use of a systemic approach, a valuable perspective from which to evaluate SPS implementation as a reliable, safe, and cost efficient energy supply of the future, is discussed.

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

Todt, Michael A.; Isenberg, Allan E.; Nanayakkara, Sanjini U.

Semiconducting transition-metal dichalcogenide (TMD) nanoflake thin films are promising large-area electrodes for photo-electrochemical solar energy conversion applications. However, their energy conversion efficiencies are typically much lower than those of bulk electrodes. It is unclear to what extent this efficiency gap stems from differences among nanoflakes (e.g., area, thickness, and surface structural features). It is also unclear whether individual exfoliated nanoflakes can achieve energy conversion efficiencies similar to those of bulk crystals. Here, we use a single-nanoflake photo-electrochemical approach to show that there are both highly active and completely inactive nanoflakes within a film. For the exfoliated MoSe 2 samples studiedmore » herein, 7% of nanoflakes are highly active champions, whose photocurrent efficiency exceeds that of the bulk crystal. However, 66% of nanoflakes are inactive spectators, which are mostly responsible for the overall lower photocurrent efficiency compared to the bulk crystal. The photocurrent collection efficiency increases with nanoflake area and decreases more at perimeter edges than at interior step edges. These observations, which are hidden in ensemble-level measurements, reveal the underlying performance issues of exfoliated TMD electrodes for photo-electrochemical energy conversion applications.« less

The Global Experience of Deployment of Energy-Efficient Technologies in High-Rise Construction

NASA Astrophysics Data System (ADS)

Potienko, Natalia D.; Kuznetsova, Anna A.; Solyakova, Darya N.; Klyueva, Yulia E.

2018-03-01

The objective of this research is to examine issues related to the increasing importance of energy-efficient technologies in high-rise construction. The aim of the paper is to investigate modern approaches to building design that involve implementation of various energy-saving technologies in diverse climates and at different structural levels, including the levels of urban development, functionality, planning, construction and engineering. The research methodology is based on the comprehensive analysis of the advanced global expertise in the design and construction of energy-efficient high-rise buildings, with the examination of their positive and negative features. The research also defines the basic principles of energy-efficient architecture. Besides, it draws parallels between the climate characteristics of countries that lead in the field of energy-efficient high-rise construction, on the one hand, and the climate in Russia, on the other, which makes it possible to use the vast experience of many countries, wholly or partially. The paper also gives an analytical review of the results arrived at by implementing energy efficiency principles into high-rise architecture. The study findings determine the impact of energy-efficient technologies on high-rise architecture and planning solutions. In conclusion, the research states that, apart from aesthetic and compositional interpretation of architectural forms, an architect nowadays has to address the task of finding a synthesis between technological and architectural solutions, which requires knowledge of advanced technologies. The study findings reveal that the implementation of modern energy-efficient technologies into high-rise construction is of immediate interest and is sure to bring long-term benefits.

A study of pricing and trading model of Blockchain & Big data-based Energy-Internet electricity

NASA Astrophysics Data System (ADS)

Fan, Tao; He, Qingsu; Nie, Erbao; Chen, Shaozhen

2018-01-01

The development of Energy-Internet is currently suffering from a series of issues, such as the conflicts among high capital requirement, low-cost, high efficiency, the spreading gap between capital demand and supply, as well as the lagged trading & valuation mechanism, any of which would hinder Energy-Internet's evolution. However, with the development of Blockchain and big-data technology, it is possible to work out solutions for these issues. Based on current situation of Energy-Internet and its requirements for future progress, this paper demonstrates the validity of employing blockchain technology to solve the problems encountered by Energy-Internet during its development. It proposes applying the blockchain and big-data technologies to pricing and trading energy products through Energy-Internet and to accomplish cyber-based energy or power's transformation from physic products to financial assets.

Energy Efficiency of D2D Multi-User Cooperation.

PubMed

Zhang, Zufan; Wang, Lu; Zhang, Jie

2017-03-28

The Device-to-Device (D2D) communication system is an important part of heterogeneous networks. It has great potential to improve spectrum efficiency, throughput and energy efficiency cooperation of multiple D2D users with the advantage of direct communication. When cooperating, D2D users expend extraordinary energy to relay data to other D2D users. Hence, the remaining energy of D2D users determines the life of the system. This paper proposes a cooperation scheme for multiple D2D users who reuse the orthogonal spectrum and are interested in the same data by aiming to solve the energy problem of D2D users. Considering both energy availability and the Signal to Noise Ratio (SNR) of each D2D user, the Kuhn-Munkres algorithm is introduced in the cooperation scheme to solve relay selection problems. Thus, the cooperation issue is transformed into a maximum weighted matching (MWM) problem. In order to enhance energy efficiency without the deterioration of Quality of Service (QoS), the link outage probability is derived according to the Shannon Equation by considering the data rate and delay. The simulation studies the relationships among the number of cooperative users, the length of shared data, the number of data packets and energy efficiency.

Re-Form: FPGA-Powered True Codesign Flow for High-Performance Computing In The Post-Moore Era

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

Cappello, Franck; Yoshii, Kazutomo; Finkel, Hal

Multicore scaling will end soon because of practical power limits. Dark silicon is becoming a major issue even more than the end of Moore’s law. In the post-Moore era, the energy efficiency of computing will be a major concern. FPGAs could be a key to maximizing the energy efficiency. In this paper we address severe challenges in the adoption of FPGA in HPC and describe “Re-form,” an FPGA-powered codesign flow.

Designing Decentralized Water and Electricity Supply System for Small Recreational Facilities in the South of Russia

NASA Astrophysics Data System (ADS)

Kasharin, D. V.

2017-11-01

The article tackles the issues of designing seasonal water and power supply systems for small recreational facilities in the south of Russia based on intelligent decision support systems. The paper proposes modular prefabricated shell water and power supply works (MPSW&PW) along with energy-efficient standalone water-treatment plants as the principal facilities compliant with the environmental and infrastructural requirements applied to specially protected areas and ensuring the least possible damage to the environment due to a maximum possible use of local construction materials characterized by impressive safety margins in highly seismic environments. The task of designing water and power supply systems requires the consideration of issues pertaining to the development of an intelligent GIS-based system for the selection of water intake sites that facilitate automation of data-processing systems using a priori scanning methods with a variable step and random directions. The paper duly addresses such issues and develops parameterized optimization algorithms for MPSW&PW shell facilities. It equally provides the substantiation of water-treatment plants intelligent design based on energy recovery reverse osmosis and nanofiltration plants that enhance the energy efficiency of such plants serving as the optimum solution for the decentralized water supply of small recreational facilities from renewable energy sources.

Will Renewable Energy Save Our Planet?

NASA Astrophysics Data System (ADS)

Bojić, Milorad

2010-06-01

This paper discusses some important fundamental issues behind application of renewable energy (RE) to evaluate its impact as a climate change mitigation technology. The discussed issues are the following: definition of renewable energy, concentration of RE by weight and volume, generation of electrical energy and its power at unit area, electrical energy demand per unit area, life time approach vs. layman approach, energy return time, energy return ratio, CO2 return time, energy mix for RES production and use, geographical distribution of RES use, huge scale of energy shift from RES to non-RES, increase in energy consumption, Thermodynamic equilibrium of earth, and probable solutions for energy future of our energy and environmental crisis of today. The future solution (that would enable to human civilization further welfare, and good living, but with lower release of CO2 in atmosphere) may not be only RES. This will rather be an energy mix that may contain nuclear energy, non-nuclear renewable energy, or fossil energy with CO2 sequestration, efficient energy technologies, energy saving, and energy consumption decrease.

Energy efficiency and allometry of movement of swimming and flying animals.

PubMed

Bale, Rahul; Hao, Max; Bhalla, Amneet Pal Singh; Patankar, Neelesh A

2014-05-27

Which animals use their energy better during movement? One metric to answer this question is the energy cost per unit distance per unit weight. Prior data show that this metric decreases with mass, which is considered to imply that massive animals are more efficient. Although useful, this metric also implies that two dynamically equivalent animals of different sizes will not be considered equally efficient. We resolve this longstanding issue by first determining the scaling of energy cost per unit distance traveled. The scale is found to be M(2/3) or M(1/2), where M is the animal mass. Second, we introduce an energy-consumption coefficient (CE) defined as energy per unit distance traveled divided by this scale. CE is a measure of efficiency of swimming and flying, analogous to how drag coefficient quantifies aerodynamic drag on vehicles. Derivation of the energy-cost scale reveals that the assumption that undulatory swimmers spend energy to overcome drag in the direction of swimming is inappropriate. We derive allometric scalings that capture trends in data of swimming and flying animals over 10-20 orders of magnitude by mass. The energy-consumption coefficient reveals that swimmers beyond a critical mass, and most fliers are almost equally efficient as if they are dynamically equivalent; increasingly massive animals are not more efficient according to the proposed metric. Distinct allometric scalings are discovered for large and small swimmers. Flying animals are found to require relatively more energy compared with swimmers.

Energy efficiency and allometry of movement of swimming and flying animals

PubMed Central

Bale, Rahul; Hao, Max; Bhalla, Amneet Pal Singh; Patankar, Neelesh A.

2014-01-01

Which animals use their energy better during movement? One metric to answer this question is the energy cost per unit distance per unit weight. Prior data show that this metric decreases with mass, which is considered to imply that massive animals are more efficient. Although useful, this metric also implies that two dynamically equivalent animals of different sizes will not be considered equally efficient. We resolve this longstanding issue by first determining the scaling of energy cost per unit distance traveled. The scale is found to be M2/3 or M1/2, where M is the animal mass. Second, we introduce an energy-consumption coefficient (CE) defined as energy per unit distance traveled divided by this scale. CE is a measure of efficiency of swimming and flying, analogous to how drag coefficient quantifies aerodynamic drag on vehicles. Derivation of the energy-cost scale reveals that the assumption that undulatory swimmers spend energy to overcome drag in the direction of swimming is inappropriate. We derive allometric scalings that capture trends in data of swimming and flying animals over 10–20 orders of magnitude by mass. The energy-consumption coefficient reveals that swimmers beyond a critical mass, and most fliers are almost equally efficient as if they are dynamically equivalent; increasingly massive animals are not more efficient according to the proposed metric. Distinct allometric scalings are discovered for large and small swimmers. Flying animals are found to require relatively more energy compared with swimmers. PMID:24821764

EU energy policies achievement by industries in decentralized areas

NASA Astrophysics Data System (ADS)

Destro, Nicola; Stoppato, Anna; Benato, Alberto; Schiro, Fabio

2017-11-01

Energy Roadmap outlined by the European Commission sets out several routes for a more sustainable, competitive and secure energy system in 2050. All the outlined scenarios consider energy efficiency, renewable energy, nuclear energy and carbon capture and storage. In this paper, more attention has been devoted to the energy efficiency issue, by the identification of new micro and small networks opportunity fed by hybrid plants in the North-East of Italy. National energy balance and national transmission system operator data allowed to collect industrial energy consumptions data on the investigated area. Applying industrial statistics to the local energy needs allows to collect a dataset including consumption information by factory and by company structure (size and employees) for each industrial sector highlighting the factory density in the area. Preliminary outcomes from the model address to the exploitation of local by-product for energy purposes.

Federally Funded Programs Related to Building Energy Use: Overlaps, Challenges, and Opportunities for Collaboration

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

Cort, Katherine A.; Butner, Ryan S.; Hostick, Donna J.

2010-10-01

As energy efficiency in buildings continues to move from discreet technology development to an integrated systems approach, the need to understand and integrate complementary goals and targets becomes more pronounced. Whether within Department of Energy’s (DOE) Building Technologies Program (BTP), across the Office of Energy Efficiency and Renewable Energy (EERE), or throughout DOE and the Federal government, mutual gains and collaboration synergies exist that are not easily achieved because of organizational and time constraints. There also cases where federal agencies may be addressing similar issues, but with different (and sometimes conflicting) outcomes in mind. This report conducts a comprehensive inventorymore » across all EERE and other relevant Federal agencies of potential activities with synergistic benefits. A taxonomy of activities with potential interdependencies is presented. The report identifies a number of federal program objectives, products, and plans related to building energy efficiency and characterizes the current structure and interactions related to these plans and programs. Areas where overlap occurs are identified as are the challenges of addressing issues related to overlapping goals and programs. Based on the input gathered from various sources, including 20 separate interviews with federal agency staff and contractor staff supporting buildings programs, this study identifies a number of synergistic opportunities and makes recommends a number of areas where further collaboration could be beneficial.« less

Deregulation strategies for local governments and the role/opportunities for energy efficiency services in the utility industry deregulation

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

Tseng, P.C.

As the future shape of the electric utility industry continues to unfold and as retail competition becomes a reality, local governments are faced with balancing the need for: (1) economic development; (2) and to avoid the potential impact of cost-shifting among residents and businesses, while ensuring reliable and universal energy services. Furthermore, local governments need to find ways to recoup potential loss of franchise and tax revenues, to ensure fair and adequate energy-efficiency programs, and to continue other social programs for low income families. This paper will address two important issues every local government in the US are facing: (1)more » the development of viable deregulation strategies before, during and after the promulgation of utility deregulation; (2) opportunities for energy efficiency services in the competitive markets to serve local governments, which typically constitutes the largest market segment in utility's service territory. This paper presents issues and challenges common to all local governments. It documents strategies that several local governments are utilizing to embrace the coming electric utility restructuring and competition challenge to the benefits of their respective communities. This paper presents the results on deregulation work by the City of Portland, Oregon, Barnstable County, Massachusetts, and Montgomery County, Maryland. The research by these local governments was sponsored by the Urban Consortium Energy Task Force and Public Technology, Inc.« less

Achieving Energy Efficiency in Accordance with Bioclimatic Architecture Principles

NASA Astrophysics Data System (ADS)

Bajcinovci, Bujar; Jerliu, Florina

2016-12-01

By using our natural resources, and through inefficient use of energy, we produce much waste that can be recycled as a useful resource, which further contributes to climate change. This study aims to address energy effective bioclimatic architecture principles, by which we can achieve a potential energy savings, estimated at thirty-three per cent, mainly through environmentally affordable reconstruction, resulting in low negative impact on the environment. The study presented in this paper investigated the Ulpiana neighbourhood of Prishtina City, focusing on urban design challenges, energy efficiency and air pollution issues. The research methods consist of empirical observations through the urban spatial area using a comparative method, in order to receive clearer data and information research is conducted within Ulpiana's urban blocks, shapes of architectural structures, with the objective focusing on bioclimatic features in terms of the morphology and microclimate of Ulpiana. Energy supply plays a key role in the economic development of any country, hence, bioclimatic design principles for sustainable architecture and energy efficiency, present an evolutive integrated strategy for achieving efficiency and healthier conditions for Kosovar communities. Conceptual findings indicate that with the integrated design strategy: energy efficiency, and passive bioclimatic principles will result in a bond of complex interrelation between nature, architecture, and community. The aim of this study is to promote structured organized actions to be taken in Prishtina, and Kosovo, which will result in improved energy efficiency in all sectors, and particularly in the residential housing sector.

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

Not Available

The Best Practices Manual was written as a part of the promotional effort for EnergySmart Schools, provided by the US Department of Energy, to educate school districts around the country about energy efficiency and renewable energy. Written specifically for architects and engineers, The Best Practices Manual is designed to help those who are responsible for designing or retrofitting schools, as well as their project managers. This manual will help design staff make informed decisions about energy and environmental issues important to the school systems and communities.

Greening Federal Facilities: An Energy, Environmental, and Economic Resource Guide for Federal Facility Managers and Designers; Second Edition

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

Wilson, A.

2001-05-16

Greening Federal Facilities, Second Edition, is a nuts-and-bolts resource guide compiled to increase energy and resource efficiency, cut waste, and improve the performance of Federal buildings and facilities. The guide highlights practical actions that facility managers, design and construction staff, procurement officials, and facility planners can take to save energy and money, improve the comfort and productivity of employees, and benefit the environment. It supports a national effort to promote energy and environmental efficiency in the nation's 500,000 Federal buildings and facilities. Topics covered include current Federal regulations; environmental and energy decision-making; site and landscape issues; building design; energy systems;more » water and wastewater; materials; waste management, and recycling; indoor environmental quality; and managing buildings.« less

Energy-efficient algorithm for broadcasting in ad hoc wireless sensor networks.

PubMed

Xiong, Naixue; Huang, Xingbo; Cheng, Hongju; Wan, Zheng

2013-04-12

Broadcasting is a common and basic operation used to support various network protocols in wireless networks. To achieve energy-efficient broadcasting is especially important for ad hoc wireless sensor networks because sensors are generally powered by batteries with limited lifetimes. Energy consumption for broadcast operations can be reduced by minimizing the number of relay nodes based on the observation that data transmission processes consume more energy than data reception processes in the sensor nodes, and how to improve the network lifetime is always an interesting issue in sensor network research. The minimum-energy broadcast problem is then equivalent to the problem of finding the minimum Connected Dominating Set (CDS) for a connected graph that is proved NP-complete. In this paper, we introduce an Efficient Minimum CDS algorithm (EMCDS) with help of a proposed ordered sequence list. EMCDS does not concern itself with node energy and broadcast operations might fail if relay nodes are out of energy. Next we have proposed a Minimum Energy-consumption Broadcast Scheme (MEBS) with a modified version of EMCDS, and aimed at providing an efficient scheduling scheme with maximized network lifetime. The simulation results show that the proposed EMCDS algorithm can find smaller CDS compared with related works, and the MEBS can help to increase the network lifetime by efficiently balancing energy among nodes in the networks.

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.

Chinese hotel general managers' perspectives on energy-saving practices

NASA Astrophysics Data System (ADS)

Zhu, Yidan

As hotels' concern about sustainability and budget-control is growing steadily, energy-saving issues have become one of the important management concerns hospitality industry face. By executing proper energy-saving practices, previous scholars believed that hotel operation costs can decrease dramatically. Moreover, they believed that conducting energy-saving practices may eventually help the hotel to gain other benefits such as an improved reputation and stronger competitive advantage. The energy-saving issue also has become a critical management problem for the hotel industry in China. Previous research has not investigated energy-saving in China's hotel segment. To achieve a better understanding of the importance of energy-saving, this document attempts to present some insights into China's energy-saving practices in the tourist accommodations sector. Results of the study show the Chinese general managers' attitudes toward energy-saving issues and the differences among the diverse hotel managers who responded to the study. Study results indicate that in China, most of the hotels' energy bills decrease due to the implementation of energy-saving equipments. General managers of hotels in operation for a shorter period of time are typically responsible for making decisions about energy-saving issues; older hotels are used to choosing corporate level concerning to this issue. Larger Chinese hotels generally have official energy-saving usage training sessions for employees, but smaller Chinese hotels sometimes overlook the importance of employee training. The study also found that for the Chinese hospitality industry, energy-saving practices related to electricity are the most efficient and common way to save energy, but older hotels also should pay attention to other ways of saving energy such as water conservation or heating/cooling system.

77 FR 73334 - Adding International Energy Efficiency (IEE) Certificate to List of Certificates a Recognized...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-10

... Classification Society May Issue AGENCY: Coast Guard, DHS. ACTION: Final rule. SUMMARY: The Coast Guard is...) Certificate to the list of certificates that a recognized classification society may issue on behalf of the... January 1, 2013. This rule will enable recognized classification societies to apply to the Coast Guard to...

A high-efficiency electromechanical battery

NASA Astrophysics Data System (ADS)

Post, Richard F.; Fowler, T. K.; Post, Stephen F.

1993-03-01

In our society there is a growing need for efficient cost-effective means for storing electrical energy. The electric auto is a prime example. Storage systems for the electric utilities, and for wind or solar power, are other examples. While electrochemical cells could in principle supply these needs, the existing E-C batteries have well-known limitations. This article addresses an alternative, the electromechanical battery (EMB). An EMB is a modular unit consisting of an evacuated housing containing a fiber-composite rotor. The rotor is supported by magnetic bearings and contains an integrally mounted permanent magnet array. This article addresses design issues for EMBs with rotors made up of nested cylinders. Issues addressed include rotational stability, stress distributions, generator/motor power and efficiency, power conversion, and cost. It is concluded that the use of EMBs in electric autos could result in a fivefold reduction (relative to the IC engine) in the primary energy input required for urban driving, with a concomitant major positive impact on our economy and on air pollution.

Performance Study of Salt Cavern Air Storage Based Non-Supplementary Fired Compressed Air Energy Storage System

NASA Astrophysics Data System (ADS)

Chen, Xiaotao; Song, Jie; Liang, Lixiao; Si, Yang; Wang, Le; Xue, Xiaodai

2017-10-01

Large-scale energy storage system (ESS) plays an important role in the planning and operation of smart grid and energy internet. Compressed air energy storage (CAES) is one of promising large-scale energy storage techniques. However, the high cost of the storage of compressed air and the low capacity remain to be solved. This paper proposes a novel non-supplementary fired compressed air energy storage system (NSF-CAES) based on salt cavern air storage to address the issues of air storage and the efficiency of CAES. Operating mechanisms of the proposed NSF-CAES are analysed based on thermodynamics principle. Key factors which has impact on the system storage efficiency are thoroughly explored. The energy storage efficiency of the proposed NSF-CAES system can be improved by reducing the maximum working pressure of the salt cavern and improving inlet air pressure of the turbine. Simulation results show that the electric-to-electric conversion efficiency of the proposed NSF-CAES can reach 63.29% with a maximum salt cavern working pressure of 9.5 MPa and 9 MPa inlet air pressure of the turbine, which is higher than the current commercial CAES plants.

Building Energy Efficiency in Rural China

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

Evans, Meredydd; Yu, Sha; Song, Bo

2014-04-01

Rural buildings in China now account for more than half of China’s total building energy use. Forty percent of the floorspace in China is in rural villages and towns. Most of these buildings are very energy inefficient, and may struggle to meet basic needs. They are cold in the winter, and often experience indoor air pollution from fuel use. The Chinese government plans to adopt a voluntary building energy code, or design standard, for rural homes. The goal is to build on China’s success with codes in urban areas to improve efficiency and comfort in rural homes. The Chinese governmentmore » recognizes rural buildings represent a major opportunity for improving national building energy efficiency. The challenges of rural China are also greater than those of urban areas in many ways because of the limited local capacity and low income levels. The Chinese government wants to expand on new programs to subsidize energy efficiency improvements in rural homes to build capacity for larger-scale improvement. This article summarizes the trends and status of rural building energy use in China. It then provides an overview of the new rural building design standard, and describes options and issues to move forward with implementation.« less

The Impact of Minimum Energy Performance Standards (MEPS) Regulation on Electricity Saving in Malaysia

NASA Astrophysics Data System (ADS)

Fatihah Salleh, Siti; Eqwan Roslan, Mohd; Isa, Aishah Mohd; Faizal Basri Nair, Mohd; Syafiqah Salleh, Siti

2018-03-01

One of Malaysia’s key strategies to promote efficient energy use in the country is to implement the minimum energy performance standards (MEPS) through the Electricity Regulations (Amendment) 2013. Five selected electrical appliances (refrigerator, air conditioner, television, domestic fans and lamp fittings) must comply with MEPS requirement in order to be sold in Malaysian market. Manufacturers, importers or distributors are issued Certificate of Approval (COA) if products are MEPS-compliant. In 2015, 1,215 COAs were issued but the number of MEPS products in the market is unknown. This work collects sales data from major manufacturers to estimate the annual sales of MEPS appliances and the cumulative electricity consumption and electricity saving. It was found that most products sold have 3-star rating and above. By year 2015, total cumulative electricity savings gained from MEPS implementation is 3,645 GWh, with air conditioner being the highest contributor (30%). In the future, it is recommended that more MEPS products and related incentives be introduced to further improve efficiency of energy use in Malaysia.

Water supply of the population as a problem of energy efficiency on the example of the Tyumen region of Russia

NASA Astrophysics Data System (ADS)

Lezier, Victoria; Gusarova, Miroslava; Kopytova, Anna

2017-10-01

The purpose of this article is to draw public attention to the problems of water supply in the city of Tyumen, the capital of the oil region and one of the most important objects in Russia from the point of view of strategic water supply, located in the region with vast freshwater resources. The article outlines main water supply problems related to the quality of drinking water, its chemical composition, and risks of water contamination by industrial effluents, problems of water transport to the consumers, problems of energy efficiency. The issues raised are part of the energy efficiency not only of the Tyumen region, but also of the Sverdlovsk region, from which the waters of the drinking basin are transited, being a sewage channel for many industrial enterprises. The article touches the issues of water protection, conservation and quality of water coming from the Velizhansky water intake, as well as the possibilities of using alternative sources of drinking water. The article analyzes legal measures, and proposals for improving work with increasing the quality of drinking water, combating melt water and pollution with oil.

The thermodynamic efficiency of computations made in cells across the range of life

NASA Astrophysics Data System (ADS)

Kempes, Christopher P.; Wolpert, David; Cohen, Zachary; Pérez-Mercader, Juan

2017-11-01

Biological organisms must perform computation as they grow, reproduce and evolve. Moreover, ever since Landauer's bound was proposed, it has been known that all computation has some thermodynamic cost-and that the same computation can be achieved with greater or smaller thermodynamic cost depending on how it is implemented. Accordingly an important issue concerning the evolution of life is assessing the thermodynamic efficiency of the computations performed by organisms. This issue is interesting both from the perspective of how close life has come to maximally efficient computation (presumably under the pressure of natural selection), and from the practical perspective of what efficiencies we might hope that engineered biological computers might achieve, especially in comparison with current computational systems. Here we show that the computational efficiency of translation, defined as free energy expended per amino acid operation, outperforms the best supercomputers by several orders of magnitude, and is only about an order of magnitude worse than the Landauer bound. However, this efficiency depends strongly on the size and architecture of the cell in question. In particular, we show that the useful efficiency of an amino acid operation, defined as the bulk energy per amino acid polymerization, decreases for increasing bacterial size and converges to the polymerization cost of the ribosome. This cost of the largest bacteria does not change in cells as we progress through the major evolutionary shifts to both single- and multicellular eukaryotes. However, the rates of total computation per unit mass are non-monotonic in bacteria with increasing cell size, and also change across different biological architectures, including the shift from unicellular to multicellular eukaryotes. This article is part of the themed issue 'Reconceptualizing the origins of life'.

Measure Guideline: Heat Pump Water Heaters in New and Existing Homes

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

Shapiro, C.; Puttagunta, S.; Owens, D.

2012-02-01

This Building America Measure Guideline is intended for builders, contractors, homeowners, and policy-makers. This document is intended to explore the issues surrounding heat pump water heaters (HPWHs) to ensure that homeowners and contractors have the tools needed to appropriately and efficiently install HPWHs. Heat pump water heaters (HPWHs) promise to significantly reduce energy consumption for domestic hot water (DHW) over standard electric resistance water heaters (ERWHs). While ERWHs perform with energy factors (EFs) around 0.9, new HPWHs boast EFs upwards of 2.0. High energy factors in HPWHs are achieved by combining a vapor compression system, which extracts heat from themore » surrounding air at high efficiencies, with electric resistance element(s), which are better suited to meet large hot water demands. Swapping ERWHs with HPWHs could result in roughly 50% reduction in water heating energy consumption for 35.6% of all U.S. households. This Building America Measure Guideline is intended for builders, contractors, homeowners, and policy-makers. While HPWHs promise to significantly reduce energy use for DHW, proper installation, selection, and maintenance of HPWHs is required to ensure high operating efficiency and reliability. This document is intended to explore the issues surrounding HPWHs to ensure that homeowners and contractors have the tools needed to appropriately and efficiently install HPWHs. Section 1 of this guideline provides a brief description of HPWHs and their operation. Section 2 highlights the cost and energy savings of HPWHs as well as the variables that affect HPWH performance, reliability, and efficiency. Section 3 gives guidelines for proper installation and maintenance of HPWHs, selection criteria for locating HPWHs, and highlights of important differences between ERWH and HPWH installations. Throughout this document, CARB has included results from the evaluation of 14 heat pump water heaters (including three recently released HPWH products) installed in existing homes in the northeast region of the United States.« less

Options to improve energy efficiency for educational building

NASA Astrophysics Data System (ADS)

Jahan, Mafruha

The cost of energy is a major factor that must be considered for educational facility budget planning purpose. The analysis of energy related issues and options can be complex and requires significant time and detailed effort. One way to facilitate the inclusion of energy option planning in facility planning efforts is to utilize a tool that allows for quick appraisal of the facility energy profile. Once such an appraisal is accomplished, it is then possible to rank energy improvement options consistently with other facility needs and requirements. After an energy efficiency option has been determined to have meaningful value in comparison with other facility planning options, it is then possible to utilize the initial appraisal as the basis for an expanded consideration of additional facility and energy use detail using the same analytic system used for the initial appraisal. This thesis has developed a methodology and an associated analytic model to assist in these tasks and thereby improve the energy efficiency of educational facilities. A detailed energy efficiency and analysis tool is described that utilizes specific university building characteristics such as size, architecture, envelop, lighting, occupancy, thermal design which allows reducing the annual energy consumption. Improving the energy efficiency of various aspects of an educational building's energy performance can be complex and can require significant time and experience to make decisions. The approach developed in this thesis initially assesses the energy design for a university building. This initial appraisal is intended to assist administrators in assessing the potential value of energy efficiency options for their particular facility. Subsequently this scoping design can then be extended as another stage of the model by local facility or planning personnel to add more details and engineering aspects to the initial screening model. This approach can assist university planning efforts to identify the most cost effective combinations of energy efficiency strategies. The model analyzes and compares the payback periods of all proposed Energy Performance Measures (EPMs) to determine which has the greatest potential value.

A Survey of Architectural Techniques For Improving Cache Power Efficiency

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

Mittal, Sparsh

Modern processors are using increasingly larger sized on-chip caches. Also, with each CMOS technology generation, there has been a significant increase in their leakage energy consumption. For this reason, cache power management has become a crucial research issue in modern processor design. To address this challenge and also meet the goals of sustainable computing, researchers have proposed several techniques for improving energy efficiency of cache architectures. This paper surveys recent architectural techniques for improving cache power efficiency and also presents a classification of these techniques based on their characteristics. For providing an application perspective, this paper also reviews several real-worldmore » processor chips that employ cache energy saving techniques. The aim of this survey is to enable engineers and researchers to get insights into the techniques for improving cache power efficiency and motivate them to invent novel solutions for enabling low-power operation of caches.« less

Evaluation of food drying with air dehumidification system: a short review

NASA Astrophysics Data System (ADS)

Djaeni, M.; Utari, F. D.; Sasongko, S. B.; Kumoro, A. C.

2018-01-01

Energy efficient drying for food and agriculture products resulting high quality products has been an important issue. Currently, about 50% of total energy for postharvest treatment was used for drying. This paper presents the evaluation of new approach namely air dehumidification system with zeolite for food drying. Zeolite is a material having affinity to water in which reduced the moisture in air. With low moisture content and relative humidity, the air can improve driving force for drying even at low temperature. Thus, the energy efficiency can be potentially enhanced and the product quality can be well retained. For proving the hypothesis, the paddy and onion have been dried using dehumidified air. As performance indicators, the drying time, product quality, and heat efficiency were evaluated. Results indicated that the drying with zeolite improved the performances significantly. At operating temperature ranging 50 - 60°C, the efficiency of drying system can reach 75% with reasonable product quality.

Advanced Decentralized Water/Energy Network Design for ...

EPA Pesticide Factsheets

In order to provide a water infrastructure that is more sustainable into and beyond the 21st century, drinking water distribution systems and wastewater collection systems must account for our diminishing water supply, increasing demands, climate change, energy cost and availability. Water efficiency must be equally addressed with energy efficiency going far beyond simply adding low flow toilets and faucets in new buildings and retro-fits. Thus, it is the goal of this research project to address these water-related issues as they relate to the U.S. Environmental Protection Agency’s (EPA) mission to safeguard human health and the environment. To inform the public.

Solar updraft power generator with radial and curved vanes

NASA Astrophysics Data System (ADS)

Hafizh, Hadyan; Hamsan, Raziff; Zamri, Aidil Azlan Ahmad; Keprawi, Mohamad Fairuz Mohamad; Shirato, Hiromichi

2018-02-01

Solar radiation is the largest source of energy available on earth and the solar updraft power generator (SUPG) is a renewable energy facility capable of harnessing its abundant power. Unlike the conventional wind turbines that harness natural wind in the atmosphere and often encounter with the intermittent issue or even complete cut-off from airflow, the SUPG creates artificial wind as a result of solar-induced convective flows. However, the SUPG has an inherent low total efficiency due to the conversion of thermal energy into pressure energy. Acknowledging the low efficiency and considering its potential as a renewable energy facility, the current work aims to increase the total efficiency by installing a series of guide walls inside the collector. Two types of guide walls were used i.e. radial and curved vanes. The result with curved vanes showed that the updraft velocity is higher compare to those without vanes. About 18% and 64% improvement of updraft velocity and mechanical power were attained respectively. Furthermore, it was observed that the role of radial vanes configuration was more to produce a smooth updraft velocity profile rather than increasing the total efficiency.

Evaluation on the Efficiency of Biomass Power Generation Industry in China

PubMed Central

Sun, Dong; Guo, Sen

2014-01-01

As a developing country with large population, China is facing the problems of energy resource shortage and growing environmental pollution arising from the coal-dominated energy structure. Biomass energy, as a kind of renewable energy with the characteristics of being easy to store and friendly to environment, has become the focus of China's energy development in the future. Affected by the advanced power generation technology and diversified geography environment, the biomass power generation projects show new features in recent years. Hence, it is necessary to evaluate the efficiency of biomass power generation industry by employing proper method with the consideration of new features. In this paper, the regional difference as a new feature of biomass power generation industry is taken into consideration, and the AR model is employed to modify the zero-weight issue when using data envelopment analysis (DEA) method to evaluate the efficiency of biomass power generation industry. 30 biomass power generation enterprises in China are selected as the sample, and the efficiency evaluation is performed. The result can provide some insights into the sustainable development of biomass power generation industry in China. PMID:25093209

75 FR 30010 - Improving Market and Planning Efficiency Through Improved Software; Notice of Agenda and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-28

... Market and Planning Efficiency Through Improved Software; Notice of Agenda and Procedures for Staff... conference to be held on June 2, 2010 and June 3, 2010, to discuss issues related to unit commitment software... Unit Commitment Software Federal Energy Regulatory Commission June 2, 2010 8 a.m Richard O'Neill, FERC...

Anaerobic digestion of food waste: A review focusing on process stability.

PubMed

Li, Lei; Peng, Xuya; Wang, Xiaoming; Wu, Di

2018-01-01

Food waste (FW) is rich in biomass energy, and increasing numbers of national programs are being established to recover energy from FW using anaerobic digestion (AD). However process instability is a common operational issue for AD of FW. Process monitoring and control as well as microbial management can be used to control instability and increase the energy conversion efficiency of anaerobic digesters. Here, we review research progress related to these methods and identify existing limitations to efficient AD; recommendations for future research are also discussed. Process monitoring and control are suitable for evaluating the current operational status of digesters, whereas microbial management can facilitate early diagnosis and process optimization. Optimizing and combining these two methods are necessary to improve AD efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

Not Available

Continuing the tradition established in prior years, this panel encompasses one of the broadest ranges of topics and issues of any panel at the Summer Study. It includes papers addressing all sectors, low-income residential to industrial, and views energy efficiency from many perspectives including programmatic, evaluation, codes, standards, legislation, technical transfer, economic development, and least-cost planning. The papers represent work being performed in most geographic regions of the United States and in the international arena, specifically Thailand, China, Europe, and Scandinavia. This delightful smorgasbord has been organized, based on general content area, into the following eight sessions: (1) new directionsmore » for low-income weatherization; (2) pursuing efficiency through legislation and standards; (3) international perspectives on energy efficiency; (4) technical transfer strategies; (5) government energy policy; (6) commercial codes and standards; (7) innovative programs; and, (8) state-of-the-art review. For these conference proceedings, individual papers are processed separately for the Energy Data Base.« less

Single-Nanoflake Photo-Electrochemistry Reveals Champion and Spectator Flakes in Exfoliated MoSe 2 Films

DOE PAGES

Todt, Michael A.; Isenberg, Allan E.; Nanayakkara, Sanjini U.; ...

2018-03-06

Semiconducting transition-metal dichalcogenide (TMD) nanoflake thin films are promising large-area electrodes for photo-electrochemical solar energy conversion applications. However, their energy conversion efficiencies are typically much lower than those of bulk electrodes. It is unclear to what extent this efficiency gap stems from differences among nanoflakes (e.g., area, thickness, and surface structural features). It is also unclear whether individual exfoliated nanoflakes can achieve energy conversion efficiencies similar to those of bulk crystals. Here, we use a single-nanoflake photo-electrochemical approach to show that there are both highly active and completely inactive nanoflakes within a film. For the exfoliated MoSe 2 samples studiedmore » herein, 7% of nanoflakes are highly active champions, whose photocurrent efficiency exceeds that of the bulk crystal. However, 66% of nanoflakes are inactive spectators, which are mostly responsible for the overall lower photocurrent efficiency compared to the bulk crystal. The photocurrent collection efficiency increases with nanoflake area and decreases more at perimeter edges than at interior step edges. These observations, which are hidden in ensemble-level measurements, reveal the underlying performance issues of exfoliated TMD electrodes for photo-electrochemical energy conversion applications.« less

Efficiency of energy recovery from municipal solid waste and the resultant effect on the greenhouse gas balance.

PubMed

Gohlke, Oliver

2009-11-01

Global warming is a focus of political interest and life-cycle assessment of waste management systems reveals that energy recovery from municipal solid waste is a key issue. This paper demonstrates how the greenhouse gas effects of waste treatment processes can be described in a simplified manner by considering energy efficiency indicators. For evaluation to be consistent, it is necessary to use reasonable system boundaries and to take the generation of electricity and the use of heat into account. The new European R1 efficiency criterion will lead to the development and implementation of optimized processes/systems with increased energy efficiency which, in turn, will exert an influence on the greenhouse gas effects of waste management in Europe. Promising technologies are: the increase of steam parameters, reduction of in-plant energy consumption, and the combined use of heat and power. Plants in Brescia and Amsterdam are current examples of good performance with highly efficient electricity generation. Other examples of particularly high heat recovery rates are the energy-from-waste (EfW) plants in Malmö and Gothenburg. To achieve the full potential of greenhouse gas reduction in waste management, it is necessary to avoid landfilling combustible wastes, for example, by means of landfill taxes and by putting incentives in place for increasing the efficiency of EfW systems.

Improvement of energy efficiency: the use of thermography and air-tightness test in verification of thermal performance of school buildings

NASA Astrophysics Data System (ADS)

Kauppinen, Timo; Siikanen, Sami

2011-05-01

The improvement of energy efficiency is the key issue after the energy performance of buildings directive came into the force in European Union countries. The city of Kuopio participate a project, in which different tools will be used, generated and tested to improve the energy efficiency of public buildings. In this project there are 2 schools, the other consuming much more heating energy than the other same type of school. In this paper the results of the thermography in normal conditions and under 50 Pa pressure drop will be presented; as well as the results of remote controlled air tightness test of the buildings. Thermography combined with air tightness test showed clearly the reasons of specific consumption differences of heating energy - also in the other hand, the measurements showed the problems in the performance of ventilation system. Thermography, air tightness test and other supporting measurements can be used together to solve energy loss problems - if these measurements will be carried out by proper way.

Evaluation of Cities in the Context of Energy Efficient Urban Planning Approach

NASA Astrophysics Data System (ADS)

Handan Yücel Yıldırım, H.; Burcu Gültekin, Arzuhan; Tanrıvermiş, Harun

2017-10-01

Due to the increase in energy need with urbanization as a result of industrialization and rapid population growth, preservation of natural resources has become impossible. As the energy generated particularly from non-renewable natural resources that are in danger of depletion such as coal, natural gas, petroleum is limited, and as environmental issues caused by energy resources increase, means of safe and continuous access to energy are searched in the world. Owing to the limited energy resources and energy dependence on foreign sources in the world, particularly in European Union countries, efforts of increasing the share of renewable energy sources in energy consumption increased in all industries, including urban planning as well. Concordantly, it is necessary to develop policies and approaches that enable utilization of domestic resources complying with the country’s conditions, and monitor developments in energy. Such policies and approaches, which must be implemented in urban planning as well, have great importance in terms of not deteriorating habitable environments of future generations while utilizing present-day energy resources, prevalence of utilization of renewable energy sources, and utilization of energy effectively. For that purpose, this paper puts forward a conceptual framework covering the principles, strategies, and methods on energy efficient urban planning approach, and discusses the energy efficient urban area examples within the scope of the suggested framework.

Performance and Safety of Lithium Ion Cells

NASA Technical Reports Server (NTRS)

Ratnakumar, B. V.; Smart, M. C.; Whitcanack, L.; Surampudi, S.; Marsh, R.

2001-01-01

This report evaluates the performance and safety of Lithium Ion (Li-Ion) cells when used in batteries. Issues discussed include the cycle life, energy efficiency, tolerance to higher charge voltage, tolerance to extended tapered charge voltage, charge on cycling, specific energy, low temperature discharge, low temperature charge, various charge characteristics, storage characteristics, and more of Li-Ion cells.

User News. Volume 17, Number 1 -- Spring 1996

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

NONE

This is a newsletter for users of the DOE-2, PowerDOE, SPARK, and BLAST building energy simulation programs. The topics for the Spring 1996 issue include the SPARK simulation environment, DOE-2 validation, listing of free fenestration software from LBNL, Web sites for building energy efficiency, the heat balance method of calculating building heating and cooling loads.

Cascade exciton-pumping engines with manipulated speed and efficiency in light-harvesting porous π-network films

PubMed Central

Gu, Cheng; Huang, Ning; Xu, Fei; Gao, Jia; Jiang, Donglin

2015-01-01

Light-harvesting antennae are the machinery for exciton pumping in natural photosynthesis, whereas cascade energy transfer through chlorophyll is key to long-distance, efficient energy transduction. Numerous artificial antennae have been developed. However, they are limited in their cascade energy-transfer abilities because of a lack of control over complex chromophore aggregation processes, which has impeded their advancement. Here we report a viable approach for addressing this issue by using a light-harvesting porous polymer film in which a three-dimensional π-network serves as the antenna and micropores segregate multiple dyes to prevent aggregation. Cascade energy-transfer engines are integrated into the films; the rate and efficiency of the energy-funneling engines are precisely manipulated by tailoring the dye components and contents. The nanofilms allow accurate and versatile luminescence engineering, resulting in the production of thirty emission hues, including blue, green, red and white. This advance may open new pathways for realising photosynthesis and photoenergy conversion. PMID:25746459

Highly Efficient Intramolecular Electrochemiluminescence Energy Transfer for Ultrasensitive Bioanalysis of Aflatoxin M1.

PubMed

Liu, Jia-Li; Zhao, Min; Zhuo, Ying; Chai, Ya-Qin; Yuan, Ruo

2017-02-03

The intermolecular electrochemiluminescence resonance energy transfer (ECL-RET) between luminol and Ru(bpy) 3 2+ was studied extensively to achieve the sensitive bioanalysis owing to the perfect spectral overlap of the donor and acceptor, but it still suffers from the challenging issue of low energy-transfer efficiency. The intramolecular ECL-RET towards the novel ECL compound containing the donor of luminol and the acceptor of Ru(bpy) 2 (mcpbpy) 2+ (Lum-Ru) was designed and investigated. With the high-efficient ECL-RET in one molecule, the highly intense ECL signal of Lum-Ru was obtained owing to the short path of energy transmission and less energy loss between luminol and Ru(bpy) 2 (mcpbpy) 2+ . Lum-Ru was further applied to construct a signal-off electrochemiluminescence (ECL) aptasensor for ultrasensitive detection of a harsh carcinogen of Aflatoxin M1 (AFM1). This sensing platform also provides a significant boost for the trace detection of other biomolecules in clinical analysis. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

NONE

This document contains the State Building Energy Codes Status prepared by Pacific Northwest National Laboratory for the U.S. Department of Energy under Contract DE-AC06-76RL01830 and dated September 1996. The U.S. Department of Energy`s Office of Codes and Standards has developed this document to provide an information resource for individuals interested in energy efficiency of buildings and the relevant building energy codes in each state and U.S. territory. This is considered to be an evolving document and will be updated twice a year. In addition, special state updates will be issued as warranted.

Mixing Efficiency in the Ocean.

PubMed

Gregg, M C; D'Asaro, E A; Riley, J J; Kunze, E

2018-01-03

Mixing efficiency is the ratio of the net change in potential energy to the energy expended in producing the mixing. Parameterizations of efficiency and of related mixing coefficients are needed to estimate diapycnal diffusivity from measurements of the turbulent dissipation rate. Comparing diffusivities from microstructure profiling with those inferred from the thickening rate of four simultaneous tracer releases has verified, within observational accuracy, 0.2 as the mixing coefficient over a 30-fold range of diapycnal diffusivities. Although some mixing coefficients can be estimated from pycnocline measurements, at present mixing efficiency must be obtained from channel flows, laboratory experiments, and numerical simulations. Reviewing the different approaches demonstrates that estimates and parameterizations for mixing efficiency and coefficients are not converging beyond the at-sea comparisons with tracer releases, leading to recommendations for a community approach to address this important issue.

Mixing Efficiency in the Ocean

NASA Astrophysics Data System (ADS)

Gregg, M. C.; D'Asaro, E. A.; Riley, J. J.; Kunze, E.

2018-01-01

Mixing efficiency is the ratio of the net change in potential energy to the energy expended in producing the mixing. Parameterizations of efficiency and of related mixing coefficients are needed to estimate diapycnal diffusivity from measurements of the turbulent dissipation rate. Comparing diffusivities from microstructure profiling with those inferred from the thickening rate of four simultaneous tracer releases has verified, within observational accuracy, 0.2 as the mixing coefficient over a 30-fold range of diapycnal diffusivities. Although some mixing coefficients can be estimated from pycnocline measurements, at present mixing efficiency must be obtained from channel flows, laboratory experiments, and numerical simulations. Reviewing the different approaches demonstrates that estimates and parameterizations for mixing efficiency and coefficients are not converging beyond the at-sea comparisons with tracer releases, leading to recommendations for a community approach to address this important issue.

Fuzzy-driven energy storage system for mitigating voltage unbalance factor on distribution network with photovoltaic system

NASA Astrophysics Data System (ADS)

Wong, Jianhui; Lim, Yun Seng; Morris, Stella; Morris, Ezra; Chua, Kein Huat

2017-04-01

The amount of small-scaled renewable energy sources is anticipated to increase on the low-voltage distribution networks for the improvement of energy efficiency and reduction of greenhouse gas emission. The growth of the PV systems on the low-voltage distribution networks can create voltage unbalance, voltage rise, and reverse-power flow. Usually these issues happen with little fluctuation. However, it tends to fluctuate severely as Malaysia is a region with low clear sky index. A large amount of clouds often passes over the country, hence making the solar irradiance to be highly scattered. Therefore, the PV power output fluctuates substantially. These issues can lead to the malfunction of the electronic based equipment, reduction in the network efficiency and improper operation of the power protection system. At the current practice, the amount of PV system installed on the distribution network is constraint by the utility company. As a result, this can limit the reduction of carbon footprint. Therefore, energy storage system is proposed as a solution for these power quality issues. To ensure an effective operation of the distribution network with PV system, a fuzzy control system is developed and implemented to govern the operation of an energy storage system. The fuzzy driven energy storage system is able to mitigate the fluctuating voltage rise and voltage unbalance on the electrical grid by actively manipulates the flow of real power between the grid and the batteries. To verify the effectiveness of the proposed fuzzy driven energy storage system, an experimental network integrated with 7.2kWp PV system was setup. Several case studies are performed to evaluate the response of the proposed solution to mitigate voltage rises, voltage unbalance and reduce the amount of reverse power flow under highly intermittent PV power output.

Energy Efficiency in Small Server Rooms: Field Surveys and Findings

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

Cheung, Iris; Greenberg, Steve; Mahdavi, Roozbeh

Fifty-seven percent of US servers are housed in server closets, server rooms, and localized data centers, in what are commonly referred to as small server rooms, which comprise 99percent of all server spaces in the US. While many mid-tier and enterprise-class data centers are owned by large corporations that consider energy efficiency a goal to minimize business operating costs, small server rooms typically are not similarly motivated. They are characterized by decentralized ownership and management and come in many configurations, which creates a unique set of efficiency challenges. To develop energy efficiency strategies for these spaces, we surveyed 30 smallmore » server rooms across eight institutions, and selected four of them for detailed assessments. The four rooms had Power Usage Effectiveness (PUE) values ranging from 1.5 to 2.1. Energy saving opportunities ranged from no- to low-cost measures such as raising cooling set points and better airflow management, to more involved but cost-effective measures including server consolidation and virtualization, and dedicated cooling with economizers. We found that inefficiencies mainly resulted from organizational rather than technical issues. Because of the inherent space and resource limitations, the most effective measure is to operate servers through energy-efficient cloud-based services or well-managed larger data centers, rather than server rooms. Backup power requirement, and IT and cooling efficiency should be evaluated to minimize energy waste in the server space. Utility programs are instrumental in raising awareness and spreading technical knowledge on server operation, and the implementation of energy efficiency measures in small server rooms.« less

Energy-efficient neural information processing in individual neurons and neuronal networks.

PubMed

Yu, Lianchun; Yu, Yuguo

2017-11-01

Brains are composed of networks of an enormous number of neurons interconnected with synapses. Neural information is carried by the electrical signals within neurons and the chemical signals among neurons. Generating these electrical and chemical signals is metabolically expensive. The fundamental issue raised here is whether brains have evolved efficient ways of developing an energy-efficient neural code from the molecular level to the circuit level. Here, we summarize the factors and biophysical mechanisms that could contribute to the energy-efficient neural code for processing input signals. The factors range from ion channel kinetics, body temperature, axonal propagation of action potentials, low-probability release of synaptic neurotransmitters, optimal input and noise, the size of neurons and neuronal clusters, excitation/inhibition balance, coding strategy, cortical wiring, and the organization of functional connectivity. Both experimental and computational evidence suggests that neural systems may use these factors to maximize the efficiency of energy consumption in processing neural signals. Studies indicate that efficient energy utilization may be universal in neuronal systems as an evolutionary consequence of the pressure of limited energy. As a result, neuronal connections may be wired in a highly economical manner to lower energy costs and space. Individual neurons within a network may encode independent stimulus components to allow a minimal number of neurons to represent whole stimulus characteristics efficiently. This basic principle may fundamentally change our view of how billions of neurons organize themselves into complex circuits to operate and generate the most powerful intelligent cognition in nature. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Improved Monte Carlo Scheme for Efficient Particle Transfer in Heterogeneous Systems in the Grand Canonical Ensemble: Application to Vapor-Liquid Nucleation.

PubMed

Loeffler, Troy D; Sepehri, Aliasghar; Chen, Bin

2015-09-08

Reformulation of existing Monte Carlo algorithms used in the study of grand canonical systems has yielded massive improvements in efficiency. Here we present an energy biasing scheme designed to address targeting issues encountered in particle swap moves using sophisticated algorithms such as the Aggregation-Volume-Bias and Unbonding-Bonding methods. Specifically, this energy biasing scheme allows a particle to be inserted to (or removed from) a region that is more acceptable. As a result, this new method showed a several-fold increase in insertion/removal efficiency in addition to an accelerated rate of convergence for the thermodynamic properties of the system.

Quantitative Effectiveness Analysis of Solar Photovoltaic Policies, Introduction of Socio-Feed-in Tariff Mechanism (SocioFIT) and its Implementation in Turkey

NASA Astrophysics Data System (ADS)

Mustafaoglu, Mustafa Sinan

Some of the main energy issues in developing countries are high dependence on non-renewable energy sources, low energy efficiency levels and as a result of this high amount of CO2 emissions. Besides, a common problem of many countries including developing countries is economic inequality problem. In the study, solar photovoltaic policies of Germany, Japan and the USA is analyzed through a quantitative analysis and a new renewable energy support mechanism called Socio Feed-in Tariff Mechanism (SocioFIT) is formed based on the analysis results to address the mentioned issues of developing countries as well as economic inequality problem by using energy savings as a funding source for renewable energy systems. The applicability of the mechanism is solidified by the calculations in case of an implementation of the mechanism in Turkey.

Abbreviated bibliography on energy development—A focus on the Rocky Mountain Region

USGS Publications Warehouse

Montag, Jessica M.; Willis, Carolyn J.; Glavin, Levi W.

2011-01-01

Energy development of all types continues to grow in the Rocky Mountain Region of the western United States. Federal resource managers increasingly need to balance energy demands, effects on the natural landscape and public perceptions towards these issues. To assist in efficient access to valuable information, this abbreviated bibliography provides citations to relevant information for myriad of issues for which resource managers must contend. The bibliography is organized by seven large topics with various sup-topics: broad energy topics (energy crisis, conservation, supply and demand, etc.); energy sources (fossil fuel, nuclear, renewable, etc.); natural landscape effects (climate change, ecosystem, mitigation, restoration, and reclamation, wildlife, water, etc.); human landscape effects (attitudes and perceptions, economics, community effects, health, Native Americans, etc.); research and technology; international research; and, methods and modeling. A large emphasis is placed on the natural and human landscape effects.

Efficient Coding and Energy Efficiency Are Promoted by Balanced Excitatory and Inhibitory Synaptic Currents in Neuronal Network

PubMed Central

Yu, Lianchun; Shen, Zhou; Wang, Chen; Yu, Yuguo

2018-01-01

Selective pressure may drive neural systems to process as much information as possible with the lowest energy cost. Recent experiment evidence revealed that the ratio between synaptic excitation and inhibition (E/I) in local cortex is generally maintained at a certain value which may influence the efficiency of energy consumption and information transmission of neural networks. To understand this issue deeply, we constructed a typical recurrent Hodgkin-Huxley network model and studied the general principles that governs the relationship among the E/I synaptic current ratio, the energy cost and total amount of information transmission. We observed in such a network that there exists an optimal E/I synaptic current ratio in the network by which the information transmission achieves the maximum with relatively low energy cost. The coding energy efficiency which is defined as the mutual information divided by the energy cost, achieved the maximum with the balanced synaptic current. Although background noise degrades information transmission and imposes an additional energy cost, we find an optimal noise intensity that yields the largest information transmission and energy efficiency at this optimal E/I synaptic transmission ratio. The maximization of energy efficiency also requires a certain part of energy cost associated with spontaneous spiking and synaptic activities. We further proved this finding with analytical solution based on the response function of bistable neurons, and demonstrated that optimal net synaptic currents are capable of maximizing both the mutual information and energy efficiency. These results revealed that the development of E/I synaptic current balance could lead a cortical network to operate at a highly efficient information transmission rate at a relatively low energy cost. The generality of neuronal models and the recurrent network configuration used here suggest that the existence of an optimal E/I cell ratio for highly efficient energy costs and information maximization is a potential principle for cortical circuit networks. Summary We conducted numerical simulations and mathematical analysis to examine the energy efficiency of neural information transmission in a recurrent network as a function of the ratio of excitatory and inhibitory synaptic connections. We obtained a general solution showing that there exists an optimal E/I synaptic ratio in a recurrent network at which the information transmission as well as the energy efficiency of this network achieves a global maximum. These results reflect general mechanisms for sensory coding processes, which may give insight into the energy efficiency of neural communication and coding. PMID:29773979

Efficient Coding and Energy Efficiency Are Promoted by Balanced Excitatory and Inhibitory Synaptic Currents in Neuronal Network.

PubMed

Yu, Lianchun; Shen, Zhou; Wang, Chen; Yu, Yuguo

2018-01-01

Selective pressure may drive neural systems to process as much information as possible with the lowest energy cost. Recent experiment evidence revealed that the ratio between synaptic excitation and inhibition (E/I) in local cortex is generally maintained at a certain value which may influence the efficiency of energy consumption and information transmission of neural networks. To understand this issue deeply, we constructed a typical recurrent Hodgkin-Huxley network model and studied the general principles that governs the relationship among the E/I synaptic current ratio, the energy cost and total amount of information transmission. We observed in such a network that there exists an optimal E/I synaptic current ratio in the network by which the information transmission achieves the maximum with relatively low energy cost. The coding energy efficiency which is defined as the mutual information divided by the energy cost, achieved the maximum with the balanced synaptic current. Although background noise degrades information transmission and imposes an additional energy cost, we find an optimal noise intensity that yields the largest information transmission and energy efficiency at this optimal E/I synaptic transmission ratio. The maximization of energy efficiency also requires a certain part of energy cost associated with spontaneous spiking and synaptic activities. We further proved this finding with analytical solution based on the response function of bistable neurons, and demonstrated that optimal net synaptic currents are capable of maximizing both the mutual information and energy efficiency. These results revealed that the development of E/I synaptic current balance could lead a cortical network to operate at a highly efficient information transmission rate at a relatively low energy cost. The generality of neuronal models and the recurrent network configuration used here suggest that the existence of an optimal E/I cell ratio for highly efficient energy costs and information maximization is a potential principle for cortical circuit networks. We conducted numerical simulations and mathematical analysis to examine the energy efficiency of neural information transmission in a recurrent network as a function of the ratio of excitatory and inhibitory synaptic connections. We obtained a general solution showing that there exists an optimal E/I synaptic ratio in a recurrent network at which the information transmission as well as the energy efficiency of this network achieves a global maximum. These results reflect general mechanisms for sensory coding processes, which may give insight into the energy efficiency of neural communication and coding.

Markov Chain Model-Based Optimal Cluster Heads Selection for Wireless Sensor Networks

PubMed Central

Ahmed, Gulnaz; Zou, Jianhua; Zhao, Xi; Sadiq Fareed, Mian Muhammad

2017-01-01

The longer network lifetime of Wireless Sensor Networks (WSNs) is a goal which is directly related to energy consumption. This energy consumption issue becomes more challenging when the energy load is not properly distributed in the sensing area. The hierarchal clustering architecture is the best choice for these kind of issues. In this paper, we introduce a novel clustering protocol called Markov chain model-based optimal cluster heads (MOCHs) selection for WSNs. In our proposed model, we introduce a simple strategy for the optimal number of cluster heads selection to overcome the problem of uneven energy distribution in the network. The attractiveness of our model is that the BS controls the number of cluster heads while the cluster heads control the cluster members in each cluster in such a restricted manner that a uniform and even load is ensured in each cluster. We perform an extensive range of simulation using five quality measures, namely: the lifetime of the network, stable and unstable region in the lifetime of the network, throughput of the network, the number of cluster heads in the network, and the transmission time of the network to analyze the proposed model. We compare MOCHs against Sleep-awake Energy Efficient Distributed (SEED) clustering, Artificial Bee Colony (ABC), Zone Based Routing (ZBR), and Centralized Energy Efficient Clustering (CEEC) using the above-discussed quality metrics and found that the lifetime of the proposed model is almost 1095, 2630, 3599, and 2045 rounds (time steps) greater than SEED, ABC, ZBR, and CEEC, respectively. The obtained results demonstrate that the MOCHs is better than SEED, ABC, ZBR, and CEEC in terms of energy efficiency and the network throughput. PMID:28241492

Commentary: Environmental nanophotonics and energy

NASA Astrophysics Data System (ADS)

Smith, Geoff B.

2011-01-01

The reasons nanophotonics is proving central to meeting the need for large gains in energy efficiency and renewable energy supply are analyzed. It enables optimum management and use of environmental energy flows at low cost and on a sufficient scale by providing spectral, directional and temporal control in tune with radiant flows from the sun, and the local atmosphere. Benefits and problems involved in large scale manufacture and deployment are discussed including how managing and avoiding safety issues in some nanosystems will occur, a process long established in nature.

Silicon-sheet and thin-film cell and module technology potential: Issue study

NASA Technical Reports Server (NTRS)

Shimada, K.; Costogue, E. N.; Ferber, R. R.

1984-01-01

The development of high-efficiency low-cost crystalline silicon ribbon and thih-film solar cells for the energy national photovoltaics program was examined. The findings of an issue study conducted are presented. The collected data identified the status of the technology, future research needs, and problems experienced. The potentials of present research activities to meet the Federal/industry long-term technical goal of achieving 15 cents per kilowatt-hour levelized PV energy cost are assessed. Recommendations for future research needs related to crystalline silicon ribbon and thin-film technologies for flat-plate collectors are also included.

Production and energetic use of biogas from energy crops and wastes in Germany.

PubMed

Weiland, Peter

2003-01-01

The production of biogas for reducing fossil CO2 emissions is one of the key strategic issues of the German government and has resulted in the development of new process techniques and new technologies for the energetic use of biogas. Progress has been made in cultivating energy crops for biogas production, in using new reactor systems for anaerobic digestion, and in applying more efficient technologies for combined heat and power production. Recently, integration of fuel cells within the anaerobic digestion process was started, and new technologies for biogas upgrading and conversion to hydrogen were tested. This article describes the trends in Germany for achieving more efficient energy production.

Greener and Sustainable Chemistry

EPA Science Inventory

The special issue on Greener and Sustainable Chemistry highlights various strategies that can be adopted to address the pollution preventive measures promoting the use of energy efficient reactions that utilize benign and bio-renewable raw materials in a relatively safer reaction...

Photosynthesis solutions to enhance productivity.

PubMed

Foyer, Christine H; Ruban, Alexander V; Nixon, Peter J

2017-09-26

The concept that photosynthesis is a highly inefficient process in terms of conversion of light energy into biomass is embedded in the literature. It is only in the past decade that the processes limiting photosynthetic efficiency have been understood to an extent that allows a step change in our ability to manipulate light energy assimilation into carbon gain. We can therefore envisage that future increases in the grain yield potential of our major crops may depend largely on increasing the efficiency of photosynthesis. The papers in this issue provide new insights into the nature of current limitations on photosynthesis and identify new targets that can be used for crop improvement, together with information on the impacts of a changing environment on the productivity of photosynthesis on land and in our oceans.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'. © 2017 The Author(s).

Photosynthesis solutions to enhance productivity

PubMed Central

2017-01-01

The concept that photosynthesis is a highly inefficient process in terms of conversion of light energy into biomass is embedded in the literature. It is only in the past decade that the processes limiting photosynthetic efficiency have been understood to an extent that allows a step change in our ability to manipulate light energy assimilation into carbon gain. We can therefore envisage that future increases in the grain yield potential of our major crops may depend largely on increasing the efficiency of photosynthesis. The papers in this issue provide new insights into the nature of current limitations on photosynthesis and identify new targets that can be used for crop improvement, together with information on the impacts of a changing environment on the productivity of photosynthesis on land and in our oceans. This article is part of the themed issue ‘Enhancing photosynthesis in crop plants: targets for improvement’. PMID:28808094

Role of national labs in energy and environmental R & D: An industrial perspective

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

Vaz, N.

1995-12-31

The perceived role of national laboratories in energy and environmental research and development is examined from an industrial perspective. A series of tables are used to summarize issues primarily related to the automotive industry. Impacts of policy on energy, environment, society, and international competition are outlined. Advances and further needs in automotive efficiency and pollution control, and research roles for national labs and industry are also summarized. 6 tabs.

Strategies to improve industrial energy efficiency

NASA Astrophysics Data System (ADS)

O'Rielly, Kristine M.

A lack of technical expertise, fueled by a lack of positive examples, can lead to companies opting not to implement energy reduction projects unless mandated by legislation. As a result, companies are missing out on exceptional opportunities to improve not only their environmental record but also save considerably on fuel costs. This study investigates the broad topic of energy efficiency within the context of the industrial sector by means of a thorough review of existing energy reduction strategies and a demonstration of their successful implementation. The study begins by discussing current industrial energy consumption trends around the globe and within the Canadian manufacturing sector. This is followed by a literature review which outlines 3 prominent energy efficiency improvement strategies currently available to companies: 1) Waste heat recovery, 2) Idle power loss reduction and production rate optimization, and lastly 3) Auxiliary equipment operational performance. Next, a broad overview of the resources and tools available to organizations looking to improve their industrial energy efficiency is provided. Following this, several case studies are presented which demonstrate the potential benefits that are available to Canadian organizations looking to improve their energy efficiency. Lastly, a discussion of a number of issues and barriers pertaining to the wide-scale implementation of industrial efficiency strategies is presented. It discusses a number of potential roadblocks, including a lack of energy consumption monitoring and data transparency. While this topic has been well researched in the past in terms of the losses encountered during various general manufacturing process streams, practically no literature exists which attempts to provide real data from companies who have implemented energy efficiency strategies. By obtaining original data directly from companies, this thesis demonstrates the potential for companies to save money and reduce GHG (greenhouse gas) emissions through the implementation of energy efficiency projects and publishes numbers which are almost impossible to find directly. By publishing success stories, it is hoped that other companies, especially SMEs (small and medium enterprises) will be able to learn from these case studies and be inspired to embark on energy efficiency projects of their own.

Improved immunization strategy to reduce energy consumption on nodes traffic

NASA Astrophysics Data System (ADS)

Yuan, Jiazheng; Zhao, Dongyan; Long, Keping; Zheng, Yongrong

2017-04-01

The increasing requirement of transmission network sizes would result in huge energy consumption with communication traffic. Green communication technologies are expected to help in reducing energy consumption impact to environment. Therefore, it is important to design energy-efficient strategy that can decrease energy consumption. This paper proposes to use the acquaintance and improved targeted immunization strategies from complex systems to resolve energy consumption issues and uses traffic as measure standard to obtain a stable threshold. The simulation results show that the improved control strategy is better and more effective to save as much energy as possible.

A survey and taxonomy on energy efficient resource allocation techniques for cloud computing systems

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

Hameed, Abdul; Khoshkbarforoushha, Alireza; Ranjan, Rajiv

In a cloud computing paradigm, energy efficient allocation of different virtualized ICT resources (servers, storage disks, and networks, and the like) is a complex problem due to the presence of heterogeneous application (e.g., content delivery networks, MapReduce, web applications, and the like) workloads having contentious allocation requirements in terms of ICT resource capacities (e.g., network bandwidth, processing speed, response time, etc.). Several recent papers have tried to address the issue of improving energy efficiency in allocating cloud resources to applications with varying degree of success. However, to the best of our knowledge there is no published literature on this subjectmore » that clearly articulates the research problem and provides research taxonomy for succinct classification of existing techniques. Hence, the main aim of this paper is to identify open challenges associated with energy efficient resource allocation. In this regard, the study, first, outlines the problem and existing hardware and software-based techniques available for this purpose. Furthermore, available techniques already presented in the literature are summarized based on the energy-efficient research dimension taxonomy. The advantages and disadvantages of the existing techniques are comprehensively analyzed against the proposed research dimension taxonomy namely: resource adaption policy, objective function, allocation method, allocation operation, and interoperability.« less

Providing Personalized Energy Management and Awareness Services for Energy Efficiency in Smart Buildings.

PubMed

Fotopoulou, Eleni; Zafeiropoulos, Anastasios; Terroso-Sáenz, Fernando; Şimşek, Umutcan; González-Vidal, Aurora; Tsiolis, George; Gouvas, Panagiotis; Liapis, Paris; Fensel, Anna; Skarmeta, Antonio

2017-09-07

Considering that the largest part of end-use energy consumption worldwide is associated with the buildings sector, there is an inherent need for the conceptualization, specification, implementation, and instantiation of novel solutions in smart buildings, able to achieve significant reductions in energy consumption through the adoption of energy efficient techniques and the active engagement of the occupants. Towards the design of such solutions, the identification of the main energy consuming factors, trends, and patterns, along with the appropriate modeling and understanding of the occupants' behavior and the potential for the adoption of environmentally-friendly lifestyle changes have to be realized. In the current article, an innovative energy-aware information technology (IT) ecosystem is presented, aiming to support the design and development of novel personalized energy management and awareness services that can lead to occupants' behavioral change towards actions that can have a positive impact on energy efficiency. Novel information and communication technologies (ICT) are exploited towards this direction, related mainly to the evolution of the Internet of Things (IoT), data modeling, management and fusion, big data analytics, and personalized recommendation mechanisms. The combination of such technologies has resulted in an open and extensible architectural approach able to exploit in a homogeneous, efficient and scalable way the vast amount of energy, environmental, and behavioral data collected in energy efficiency campaigns and lead to the design of energy management and awareness services targeted to the occupants' lifestyles. The overall layered architectural approach is detailed, including design and instantiation aspects based on the selection of set of available technologies and tools. Initial results from the usage of the proposed energy aware IT ecosystem in a pilot site at the University of Murcia are presented along with a set of identified open issues for future research.

Providing Personalized Energy Management and Awareness Services for Energy Efficiency in Smart Buildings

PubMed Central

Fotopoulou, Eleni; Tsiolis, George; Gouvas, Panagiotis; Liapis, Paris; Fensel, Anna; Skarmeta, Antonio

2017-01-01

Considering that the largest part of end-use energy consumption worldwide is associated with the buildings sector, there is an inherent need for the conceptualization, specification, implementation, and instantiation of novel solutions in smart buildings, able to achieve significant reductions in energy consumption through the adoption of energy efficient techniques and the active engagement of the occupants. Towards the design of such solutions, the identification of the main energy consuming factors, trends, and patterns, along with the appropriate modeling and understanding of the occupants’ behavior and the potential for the adoption of environmentally-friendly lifestyle changes have to be realized. In the current article, an innovative energy-aware information technology (IT) ecosystem is presented, aiming to support the design and development of novel personalized energy management and awareness services that can lead to occupants’ behavioral change towards actions that can have a positive impact on energy efficiency. Novel information and communication technologies (ICT) are exploited towards this direction, related mainly to the evolution of the Internet of Things (IoT), data modeling, management and fusion, big data analytics, and personalized recommendation mechanisms. The combination of such technologies has resulted in an open and extensible architectural approach able to exploit in a homogeneous, efficient and scalable way the vast amount of energy, environmental, and behavioral data collected in energy efficiency campaigns and lead to the design of energy management and awareness services targeted to the occupants’ lifestyles. The overall layered architectural approach is detailed, including design and instantiation aspects based on the selection of set of available technologies and tools. Initial results from the usage of the proposed energy aware IT ecosystem in a pilot site at the University of Murcia are presented along with a set of identified open issues for future research. PMID:28880227

ANSI/ASHRAE/IES Standard 90.1-2013 Preliminary Determination: Qualitative Analysis

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

Halverson, Mark A.; Hart, Reid; Athalye, Rahul A.

2014-03-01

Section 304(b) of the Energy Conservation and Production Act (ECPA), as amended, requires the Secretary of Energy to make a determination each time a revised version of ASHRAE Standard 90.1 is published with respect to whether the revised standard would improve energy efficiency in commercial buildings. When the U.S. Department of Energy (DOE) issues an affirmative determination on Standard 90.1, states are statutorily required to certify within two years that they have reviewed and updated the commercial provisions of their building energy code, with respect to energy efficiency, to meet or exceed the revised standard. This report provides a preliminarymore » qualitative analysis of all addenda to ANSI/ASHRAE/IES Standard 90.1-2010 (referred to as Standard 90.1-2010 or 2010 edition) that were included in ANSI/ASHRAE/IES Standard 90.1-2013 (referred to as Standard 90.1-2013 or 2013 edition).« less

Daylighting as a design and energy strategy: Overview of opportunities and conflicts

NASA Astrophysics Data System (ADS)

Selkowitz, S.

1981-06-01

The potentials and problems associated with using daylight both to improve visual performance and interior aesthetics and to reduce electrical lighting energy consumption and peak electric loads are reviewed. Use of daylighting as a design strategy is not always synonymous with effective use of daylighting as an energy-saving strategy unless both approaches are jointly pursued by the design team. Criteria for visual performance, disability and discomfort glare, historical perspectives on daylight utilization, building form as a limit to daylight penetration, beam sunlighting strategies, luminous efficacy of daylight versus efficient electric light sources, comparative thermal impacts, peak load and load management potential, and nonenergy benefits are reviewed. Although the energy benefits of daylighting can be oversold, it is concluded that in most cases a solid understanding of the energy and design issues should produce energy efficiency and pleasing working environments.

Deconstructing Biomass [part of The frontiers of energy

DOE PAGES

Armstrong, Robert C.; Wolfram, Catherine; de Jong, Krijn P.; ...

2016-01-11

Great strides have been made over the past century in our ability to harness energy sources, leading to profound transformations — both good and bad — in society. Looking at the energy system of today, it is clear that meeting the energy needs of the world now and in the years to come requires the concerted efforts of many different actors across a range of technologies and approaches. In this Feature, ten leading experts in energy research share their vision of what challenges their respective fields need to address in the coming decades. The issues being faced are diverse andmore » multifaceted, from the search for better materials for fuels, to the design of energy policy and markets for the developing world. However, a common theme emerges: changes to adapt and improve our energy system are greatly needed. As a result, by improving our mutual understanding of the issues faced by each area of energy research, these changes can happen more smoothly, efficiently and rapidly.« less

Poisoning of Heat Pipes

NASA Technical Reports Server (NTRS)

Gillies, Donald; Lehoczky, Sandor; Palosz, Witold; Carpenter, Paul; Salvail, Pat

2007-01-01

Thermal management is critical to space exploration efforts. In particular, efficient transfer and control of heat flow is essential when operating high energy sources such as nuclear reactors. Thermal energy must be transferred to various energy conversion devices, and to radiators for safe and efficient rejection of excess thermal energy. Applications for space power demand exceptionally long periods of time with equipment that is accessible for limited maintenance only. Equally critical is the hostile and alien environment which includes high radiation from the reactor and from space (galactic) radiation. In space or lunar applications high vacuum is an issue, while in Martian operations the systems will encounter a CO2 atmosphere. The effect of contact at high temperature with local soil (regolith) in surface operations on the moon or other terrestrial bodies (Mars, asteroids) must be considered.

Analyses of Public Utility Building - Students Designs, Aimed at their Energy Efficiency Improvement

NASA Astrophysics Data System (ADS)

Wołoszyn, Marek Adam

2017-10-01

Public utility buildings are formally, structurally and functionally complex entities. Frequently, the process of their design involves the retroactive reconsideration of energy engineering issues, once a building concept has already been completed. At that stage, minor formal corrections are made along with the design of the external layer of the building in order to satisfy applicable standards. Architecture students do the same when designing assigned public utility buildings. In order to demonstrate energy-related defects of building designs developed by students, the conduct of analyses was proposed. The completed designs of public utility buildings were examined with regard to energy efficiency of the solutions they feature through the application of the following programs: Ecotect, Vasari, and in case of simpler analyses ArchiCad program extensions were sufficient.

Impact of in-band interference on a wake-up radio system in wireless sensor networks

NASA Astrophysics Data System (ADS)

Lebreton, J. M.; Murad, N. M.; Lorion, R.

2017-05-01

The energy efficiency of Wireless Sensor Networks (WSNs) is considerably improved with Wake-up Radio (WuR) systems. However, their resilience to interference is often neglected in the literature. This might be an issue due to the proliferation of wireless devices and the growing field of internet of things. In this paper, we evaluate the impact of in-band interference from wireless devices on a WuR system. The approach proves that WuR systems are still performing well when coexisting with external wireless networks, even if the energy-efficiency is slightly reduced.

The dilemmas of bicycle planning

DOT National Transportation Integrated Search

1999-03-02

Since the 1970s, the bicycle has been a motherhood issue for U.S. transportation planning. At least in the abstract, everyone is in favor of increased use of these non-polluting, energy-efficient, quiet, and fitnesspromoting vehicles. However, when o...

Design and analysis of electricity markets

NASA Astrophysics Data System (ADS)

Sioshansi, Ramteen Mehr

Restructured competitive electricity markets rely on designing market-based mechanisms which can efficiently coordinate the power system and minimize the exercise of market power. This dissertation is a series of essays which develop and analyze models of restructured electricity markets. Chapter 2 studies the incentive properties of a co-optimized market for energy and reserves that pays reserved generators their implied opportunity cost---which is the difference between their stated energy cost and the market-clearing price for energy. By analyzing the market as a competitive direct revelation mechanism we examine the properties of efficient equilibria and demonstrate that generators have incentives to shade their stated costs below actual costs. We further demonstrate that the expected energy payments of our mechanism is less than that in a disjoint market for energy only. Chapter 3 is an empirical validation of a supply function equilibrium (SFE) model. By comparing theoretically optimal supply functions and actual generation offers into the Texas spot balancing market, we show the SFE to fit the actual behavior of the largest generators in market. This not only serves to validate the model, but also demonstrates the extent to which firms exercise market power. Chapters 4 and 5 examine equity, incentive, and efficiency issues in the design of non-convex commitment auctions. We demonstrate that different near-optimal solutions to a central unit commitment problem which have similar-sized optimality gaps will generally yield vastly different energy prices and payoffs to individual generators. Although solving the mixed integer program to optimality will overcome such issues, we show that this relies on achieving optimality of the commitment---which may not be tractable for large-scale problems within the allotted timeframe. We then simulate and compare a competitive benchmark for a market with centralized and self commitment in order to bound the efficiency losses stemming from coordination losses (cost of anarchy) in a decentralized market.

Integrating Variable Renewable Energy - Russia

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

To foster sustainable, low-emission development, many countries are establishing ambitious renewable energy targets for their electricity supply. Because solar and wind tend to be more variable and uncertain than conventional sources, meeting these targets will involve changes to power system planning and operations. Grid integration is the practice of developing efficient ways to deliver variable renewable energy (VRE) to the grid. Good integration methods maximize the cost-effectiveness of incorporating VRE into the power system while maintaining or increasing system stability and reliability. When considering grid integration, policy makers, regulators, and system operators consider a variety of issues, which can bemore » organized into four broad topics: New Renewable Energy Generation, New Transmission, Increased System Flexibility, Planning for a High RE Future. This is a Russian-language translation of Integrating Variable Renewable Energy into the Grid: Key Issues, Greening the Grid, originally published in English in May 2015.« less

Quantitative Financial Analysis of Alternative Energy Efficiency Shareholder Incentive Mechanisms

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

Cappers, Peter; Goldman, Charles; Chait, Michele

2008-08-03

Rising energy prices and climate change are central issues in the debate about our nation's energy policy. Many are demanding increased energy efficiency as a way to help reduce greenhouse gas emissions and lower the total cost of electricity and energy services for consumers and businesses. Yet, as the National Action Plan on Energy Efficiency (NAPEE) pointed out, many utilities continue to shy away from seriously expanding their energy efficiency program offerings because they claim there is insufficient profit-motivation, or even a financial disincentive, when compared to supply-side investments. With the recent introduction of Duke Energy's Save-a-Watt incentive mechanism andmore » ongoing discussions about decoupling, regulators and policymakers are now faced with an expanded and diverse landscape of financial incentive mechanisms, Determining the 'right' way forward to promote deep and sustainable demand side resource programs is challenging. Due to the renaissance that energy efficiency is currently experiencing, many want to better understand the tradeoffs in stakeholder benefits between these alternative incentive structures before aggressively embarking on a path for which course corrections can be time-consuming and costly. Using a prototypical Southwest utility and a publicly available financial model, we show how various stakeholders (e.g. shareholders, ratepayers, etc.) are affected by these different types of shareholder incentive mechanisms under varying assumptions about program portfolios. This quantitative analysis compares the financial consequences associated with a wide range of alternative incentive structures. The results will help regulators and policymakers better understand the financial implications of DSR program incentive regulation.« less

Comparative Study Between Wind and Photovoltaic (PV) Systems

NASA Astrophysics Data System (ADS)

Taha, Wesam

This paper reviews two renewable energy systems; wind and photovoltaic (PV) systems. The common debate between the two of them is to conclude which one is better, in terms of cost and efficiency. Therefore, comparative study, in terms of cost and efficiency, is attempted. Regarding total cost of both, wind and PV systems, many parameters must be taken into consideration such as availability of energy (either wind or solar), operation and maintenance, availability of costumers, political influence, and the components used in building the system. The main components and parameters that play major role in determining the overall efficiency of wind systems are the wind turbine generator (WTG), gearbox and control technologies such as power, and speed control. On the other hand, in grid-connected PV systems (GCPVS), converter architecture along with maximum power point tracking (MPPT) algorithm and inverter topologies are the issues that affects the efficiency significantly. Cost and efficiency analyses of both systems have been carried out based on the statistics available till today and would be useful in the progress of renewable energy penetration throughout the world.

Energy demand for materials in an international context.

PubMed

Worrell, Ernst; Carreon, Jesus Rosales

2017-06-13

Materials are everywhere and have determined society. The rapid increase in consumption of materials has led to an increase in the use of energy and release of greenhouse gas (GHG) emissions. Reducing emissions in material-producing industries is a key challenge. If all of industry switched to current best practices, the energy-efficiency improvement potential would be between 20% and 35% for most sectors. While these are considerable potentials, especially for sectors that have historically paid a lot of attention to energy-efficiency improvement, realization of these potentials under current 'business as usual' conditions is slow due to a large variety of barriers and limited efforts by industry and governments around the world. Importantly, the potentials are not sufficient to achieve the deep reductions in carbon emissions that will be necessary to stay within the climate boundaries as agreed in the 2015 Paris Conference of Parties. Other opportunities need to be included in the menu of options to mitigate GHG emissions. It is essential to develop integrated policies combining energy efficiency, renewable energy and material efficiency and material demand reduction, offering the most economically attractive way to realize deep reductions in carbon emissions.This article is part of the themed issue 'Material demand reduction'. © 2017 The Author(s).

Exciton size and quantum transport in nanoplatelets

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

Pelzer, Kenley M., E-mail: kpelzer@anl.gov; Gray, Stephen K.; Darling, Seth B.

2015-12-14

Two-dimensional nanoplatelets (NPLs) are an exciting class of materials with promising optical and energy transport properties. The possibility of efficient energy transport between nanoplatelets raises questions regarding the nature of energy transfer in these thin, laterally extended systems. A challenge in understanding exciton transport is the uncertainty regarding the size of the exciton. Depending on the material and defects in the nanoplatelet, an exciton could plausibly extend over an entire plate or localize to a small region. The variation in possible exciton sizes raises the question how exciton size impacts the efficiency of transport between nanoplatelet structures. Here, we exploremore » this issue using a quantum master equation approach. This method goes beyond the assumptions of Förster theory to allow for quantum mechanical effects that could increase energy transfer efficiency. The model is extremely flexible in describing different systems, allowing us to test the effect of varying the spatial extent of the exciton. We first discuss qualitative aspects of the relationship between exciton size and transport and then conduct simulations of exciton transport between NPLs for a range of exciton sizes and environmental conditions. Our results reveal that exciton size has a strong effect on energy transfer efficiency and suggest that manipulation of exciton size may be useful in designing NPLs for energy transport.« less

Exciton size and quantum transport in nanoplatelets.

PubMed

Pelzer, Kenley M; Darling, Seth B; Gray, Stephen K; Schaller, Richard D

2015-12-14

Two-dimensional nanoplatelets (NPLs) are an exciting class of materials with promising optical and energy transport properties. The possibility of efficient energy transport between nanoplatelets raises questions regarding the nature of energy transfer in these thin, laterally extended systems. A challenge in understanding exciton transport is the uncertainty regarding the size of the exciton. Depending on the material and defects in the nanoplatelet, an exciton could plausibly extend over an entire plate or localize to a small region. The variation in possible exciton sizes raises the question how exciton size impacts the efficiency of transport between nanoplatelet structures. Here, we explore this issue using a quantum master equation approach. This method goes beyond the assumptions of Förster theory to allow for quantum mechanical effects that could increase energy transfer efficiency. The model is extremely flexible in describing different systems, allowing us to test the effect of varying the spatial extent of the exciton. We first discuss qualitative aspects of the relationship between exciton size and transport and then conduct simulations of exciton transport between NPLs for a range of exciton sizes and environmental conditions. Our results reveal that exciton size has a strong effect on energy transfer efficiency and suggest that manipulation of exciton size may be useful in designing NPLs for energy transport.

Smart Buildings and Demand Response

NASA Astrophysics Data System (ADS)

Kiliccote, Sila; Piette, Mary Ann; Ghatikar, Girish

2011-11-01

Advances in communications and control technology, the strengthening of the Internet, and the growing appreciation of the urgency to reduce demand side energy use are motivating the development of improvements in both energy efficiency and demand response (DR) systems in buildings. This paper provides a framework linking continuous energy management and continuous communications for automated demand response (Auto-DR) in various times scales. We provide a set of concepts for monitoring and controls linked to standards and procedures such as Open Automation Demand Response Communication Standards (OpenADR). Basic building energy science and control issues in this approach begin with key building components, systems, end-uses and whole building energy performance metrics. The paper presents a framework about when energy is used, levels of services by energy using systems, granularity of control, and speed of telemetry. DR, when defined as a discrete event, requires a different set of building service levels than daily operations. We provide examples of lessons from DR case studies and links to energy efficiency.

Experience implementing energy standards for commercial buildings and its lessons for the Philippines

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

Busch, John; Deringer, Joseph

1998-10-01

Energy efficiency standards for buildings have been adopted in over forty countries. This policy mechanism is pursued by governments as a means of increasing energy efficiency in the buildings sector, which typically accounts for about a third of most nations' energy consumption and half of their electricity consumption. This study reports on experience with implementation of energy standards for commercial buildings in a number of countries and U.S. states. It is conducted from the perspective of providing useful input to the Government of the Philippines' (GOP) current effort at implementing their building energy standard. While the impetus for this workmore » is technical assistance to the Philippines, the intent is to shed light on the broader issues attending implementation of building energy standards that would be applicable there and elsewhere. The background on the GOP building energy standard is presented, followed by the objectives for the study, the approach used to collect and analyze information about other jurisdictions' implementation experience, results, and conclusions and recommendations.« less

Libraries and the Environment.

ERIC Educational Resources Information Center

LaRue, James; And Others

1991-01-01

Three articles address issues that relate to libraries and the environment. Highlights include recycling projects; buying recycled paper products and other ecology-minded purchasing ideas; energy-efficient libraries; indoor pollution problems; a list of environmental information sources; designing library buildings; and activities that libraries…

78 FR 16443 - Energy Efficiency Program for Consumer Products: Energy Conservation Standards for Ceiling Fans...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-15

... with medium screw base sockets, as well as pin-based sockets. (42 U.S.C. 6295(ff)(2)-(3)) The statute... (including candelabra screw base sockets) by January 1, 2007, and if DOE failed to issue such standards by... standards for light kits with sockets other than medium-screw base or pin-based fluorescent lamps in the CFR...

RTU Comparison Calculator Enhancement Plan

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

Miller, James D.; Wang, Weimin; Katipamula, Srinivas

Over the past two years, Department of Energy’s Building Technologies Office (BTO) has been investigating ways to increase the operating efficiency of the packaged rooftop units (RTUs) in the field. First, by issuing a challenge to the RTU manufactures to increase the integrated energy efficiency ratio (IEER) by 60% over the existing ASHRAE 90.1-2010 standard. Second, by evaluating the performance of an advanced RTU controller that reduces the energy consumption by over 40%. BTO has previously also funded development of a RTU comparison calculator (RTUCC). RTUCC is a web-based tool that provides the user a way to compare energy andmore » cost savings for two units with different efficiencies. However, the RTUCC currently cannot compare savings associated with either the RTU Challenge unit or the advanced RTU controls retrofit. Therefore, BTO has asked PNNL to enhance the tool so building owners can compare energy and savings associated with this new class of products. This document provides the details of the enhancements that are required to support estimating energy savings from use of RTU challenge units or advanced controls on existing RTUs.« less

Donor-Acceptor-Collector Ternary Crystalline Films for Efficient Solid-State Photon Upconversion.

PubMed

Ogawa, Taku; Hosoyamada, Masanori; Yurash, Brett; Nguyen, Thuc-Quyen; Yanai, Nobuhiro; Kimizuka, Nobuo

2018-06-25

It is pivotal to achieve efficient triplet-triplet annihilation based photon upconversion (TTA-UC) in the solid-state for enhancing potentials of renewable energy production devices. However, the UC efficiency of solid materials is largely limited by low fluorescence quantum yields that originate from the aggregation of TTA-UC chromophores, and also by severe back energy transfer from the acceptor singlet state to the singlet state of the triplet donor in the condensed state. In this work, to overcome these issues, we introduce a highly fluorescent singlet energy collector as the third component of donor-doped acceptor crystalline films, in which dual energy migration, i.e., triplet energy migration for TTA-UC and succeeding singlet energy migration for transferring energy to a collector, takes place. To demonstrate this scheme, a highly fluorescent singlet energy collector was added as the third component of donor-doped acceptor crystalline films. An anthracene-based acceptor containing alkyl chains and a carboxylic moiety is mixed with the triplet donor Pt(II) octaethylporphyrin (PtOEP) and the energy collector 2,5,8,11-tetra- tert-butylperylene (TTBP) in solution, and spin-coating of the mixed solution gives acceptor films of nanofibrous crystals homogeneously doped with PtOEP and TTBP. Interestingly, delocalized singlet excitons in acceptor crystals are found to diffuse effectively over the distance of ~37 nm. Thanks to this high diffusivity, only 0.5 mol% of doped TTBP can harvest most of the singlet excitons, which successfully doubles the solid-state fluorescent quantum yield of acceptor/TTBP blend films to 76%. Furthermore, since the donor PtOEP and the collector TTBP are separately isolated in the nanofibrous acceptor crystals, the singlet back energy transfer from the collector to the donor is effectively avoided. Such efficient singlet energy collection and inhibited back energy transfer processes result in a large increase of UC efficiency up to 9.0%, offering rational design principles towards ultimately efficient solid-state upconverters.

A knee-mounted biomechanical energy harvester with enhanced efficiency and safety

NASA Astrophysics Data System (ADS)

Chen, Chao; Chau, Li Yin; Liao, Wei-Hsin

2017-06-01

Energy harvesting is becoming a major limiting issue for many portable devices. When undertaking any activity, the human body generates a significant amount of biomechanical energy, which can be collected by means of a portable energy harvester. This energy provides a method of powering portable devices such as prosthetic limbs. In this paper, a knee-mounted energy harvester with enhanced efficiency and safety is proposed and developed to convert mechanical energy into electricity during human motion. This device can change the bi-directional knee input into uni-directional rotation for an electromagnetic generator using a specially designed transmission system. Without the constraint of induced impact on the human body, this device can harvest biomechanical energy from both knee flexion and extension, improving the harvesting efficiency over previous single-direction energy harvesters. It can also provide protection from device malfunction, and increase the safety of current biomechanical energy harvesters. A highly compact and light prototype is developed taking into account human kinematics. The biomechanical energy harvesting system is also modeled and analyzed. The prototype is tested under different conditions including walking, running and climbing stairs, to evaluate the energy harvesting performance and effect on the human gait. The experimental results show that the prototype can harvest an average power of 3.6 W at 1.5 m s-1 walking speed, which is promising for portable electronic devices.

Competition and Cooperation of Distributed Generation and Power System

NASA Astrophysics Data System (ADS)

Miyake, Masatoshi; Nanahara, Toshiya

Advances in distributed generation technologies together with the deregulation of an electric power industry can lead to a massive introduction of distributed generation. Since most of distributed generation will be interconnected to a power system, coordination and competition between distributed generators and large-scale power sources would be a vital issue in realizing a more desirable energy system in the future. This paper analyzes competitions between electric utilities and cogenerators from the viewpoints of economic and energy efficiency based on the simulation results on an energy system including a cogeneration system. First, we examine best response correspondence of an electric utility and a cogenerator with a noncooperative game approach: we obtain a Nash equilibrium point. Secondly, we examine the optimum strategy that attains the highest social surplus and the highest energy efficiency through global optimization.

Energy Efficient In-network RFID Data Filtering Scheme in Wireless Sensor Networks

PubMed Central

Bashir, Ali Kashif; Lim, Se-Jung; Hussain, Chauhdary Sajjad; Park, Myong-Soon

2011-01-01

RFID (Radio frequency identification) and wireless sensor networks are backbone technologies for pervasive environments. In integration of RFID and WSN, RFID data uses WSN protocols for multi-hop communications. Energy is a critical issue in WSNs; however, RFID data contains a lot of duplication. These duplications can be eliminated at the base station, but unnecessary transmissions of duplicate data within the network still occurs, which consumes nodes’ energy and affects network lifetime. In this paper, we propose an in-network RFID data filtering scheme that efficiently eliminates the duplicate data. For this we use a clustering mechanism where cluster heads eliminate duplicate data and forward filtered data towards the base station. Simulation results prove that our approach saves considerable amounts of energy in terms of communication and computational cost, compared to existing filtering schemes. PMID:22163999

Energy Efficiency Strategies for Municipal Wastewater Treatment Facilities

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

Daw, J.; Hallett, K.; DeWolfe, J.

2012-01-01

Water and wastewater systems are significant energy consumers with an estimated 3%-4% of total U.S. electricity consumption used for the movement and treatment of water and wastewater. Water-energy issues are of growing importance in the context of water shortages, higher energy and material costs, and a changing climate. In this economic environment, it is in the best interest for utilities to find efficiencies, both in water and energy use. Performing energy audits at water and wastewater treatment facilities is one way community energy managers can identify opportunities to save money, energy, and water. In this paper the importance of energymore » use in wastewater facilities is illustrated by a case study of a process energy audit performed for Crested Butte, Colorado's wastewater treatment plant. The energy audit identified opportunities for significant energy savings by looking at power intensive unit processes such as influent pumping, aeration, ultraviolet disinfection, and solids handling. This case study presents best practices that can be readily adopted by facility managers in their pursuit of energy and financial savings in water and wastewater treatment. This paper is intended to improve community energy managers understanding of the role that the water and wastewater sector plays in a community's total energy consumption. The energy efficiency strategies described provide information on energy savings opportunities, which can be used as a basis for discussing energy management goals with water and wastewater treatment facility managers.« less

Solar-energy mobile water aerators are efficient for restoring eutrophic water

NASA Astrophysics Data System (ADS)

Wang, Y. Y.; Xu, Z. X.

2017-01-01

Surface water eutrophication has become a worldwide social issue. large amounts of secondhand energy, high capital investment are required, and most ecosystem disturbances will arise in the conventional eutrophication restoration measures. However, mobile solar-energy water aerator has the better oxygen transfer rate, hydrodynamic condition and can be used in the large waterbody for its cruising character. Second, the device is low carbon and sustainable for the solar photovoltaic system applications. So the device can be widely used in the eutrophication restoration.

Data Center Energy Efficiency Measurement Assessment Kit Guide and Specification

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

None

2012-10-26

A portable and temporary wireless mesh assessment kit can be used to speed up and reduce the costs of a data center energy use assessment and overcome the issues with respect to shutdowns. The assessment kit is comprised of temperature, relative humidity, and pressure sensors. Also included are power meters that can be installed on computer room air conditioners (CRACs) without intrusive interruption of data center operations. The assessment kit produces data required for a detailed energy assessment of the data center.

The assessment of global thermo-energy performances of existing district heating systems optimized by harnessing renewable energy sources

NASA Astrophysics Data System (ADS)

Şoimoşan, Teodora M.; Danku, Gelu; Felseghi, Raluca A.

2017-12-01

Within the thermo-energy optimization process of an existing heating system, the increase of the system's energy efficiency and speeding-up the transition to green energy use are pursued. The concept of multi-energy district heating system, with high harnessing levels of the renewable energy sources (RES) in order to produce heat, is expected to be the key-element in the future urban energy infrastructure, due to the important role it can have in the strategies of optimizing and decarbonizing the existing district heating systems. The issues that arise are related to the efficient integration of different technologies of harnessing renewable energy sources in the energy mix and to the increase of the participation levels of RES, respectively. For the holistic modeling of the district heating system, the concept of the energy hub was used, where the synergy of different primary forms of entered energy provides the system a high degree energy security and flexibility in operation. The optimization of energy flows within the energy hub allows the optimization of the thermo-energy district system in order to approach the dual concept of smart city & smart energy.

Middle-Aged Thinking.

ERIC Educational Resources Information Center

Nixon, Charles W.

1998-01-01

Examines renovation issues involving 30- and 40-year-old school facilities. Explores ways a school district can renovate old buildings to first-class cost-effective facilities while avoiding excessive transition costs. Discussions include installation of new technology and the resulting wiring demands, and developing more energy-efficient heating…

Energy and Energy Cost Savings Analysis of the 2015 IECC for Commercial Buildings

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

Zhang, Jian; Xie, YuLong; Athalye, Rahul A.

As required by statute (42 USC 6833), DOE recently issued a determination that ANSI/ASHRAE/IES Standard 90.1-2013 would achieve greater energy efficiency in buildings subject to the code compared to the 2010 edition of the standard. Pacific Northwest National Laboratory (PNNL) conducted an energy savings analysis for Standard 90.1-2013 in support of its determination . While Standard 90.1 is the model energy standard for commercial and multi-family residential buildings over three floors (42 USC 6833), many states have historically adopted the International Energy Conservation Code (IECC) for both residential and commercial buildings. This report provides an assessment as to whether buildingsmore » constructed to the commercial energy efficiency provisions of the 2015 IECC would save energy and energy costs as compared to the 2012 IECC. PNNL also compared the energy performance of the 2015 IECC with the corresponding Standard 90.1-2013. The goal of this analysis is to help states and local jurisdictions make informed decisions regarding model code adoption.« less

Energy Pooling Upconversion in Free Space and Optical Cavities

NASA Astrophysics Data System (ADS)

LaCount, Michael D.

The ability to efficiently convert the wavelength of light has value in a wide range of disciplines that include the fields of photovoltaics, plant growth, optics and medicine. The processes by which such transformations are carried out are known as upconversions and downconversions. There are several ways to up/down convert light, each with its own attributes, issues, and competing mechanisms. Most are associated with one-body or two-body processes. Three-body dynamics are also possible though, going by the names of quantum cutting (downconversion) and energy pooling (upconversion). These use virtual excited electronic states to mediate conversions as has been experimentally realized using lanthanide ions embedded in wide bandgap materials. The use of lanthanides to convert light is not ideal due to their relative scarcity, toxicity, and the limited range of light frequencies that can be absorbed and emitted. Organic molecules, on the other hand, are typically non-toxic, are made up of abundant elements, and can be designed with tailored spectral properties. At issue is whether or not they can be used to carry out efficient energy pooling, the central question to be answered in this thesis. The research presented here draws on a perturbative quantum electrodynamics framework previously established for generic energy pooling. It was used to develop a computational methodology for determining the rate of energy pooling and its competing processes. This, in turn, draws on a combination of time-dependent density functional theory, quantum electrodynamics, and perturbation theory to generate the requisite material property data. This computational model was applied to two test systems consisting of stilbene-fluorescein and hexabenzocoronene-oligothiophene. The stilbene-fluorescein system was found to have a maximum energy pooling rate efficiency (as compared to competing processes) of 17% and the hexabenzocoronene-oligothiophene system was found to have a maximum energy pooling rate efficiency of 99%. This demonstrates that the energy pooling rate can be made faster than its competing processes. Based on the results of this study, a set of design rules was developed to optimize the rate efficiency of energy pooling. Prior to this research, no attempt had been made to determine if energy pooling could be made to out-pace competing processes--i.e. whether or not a molecular system could be designed to utilize energy pooling as an efficient means of upconversion. This initial investigation was part of a larger effort involving a team of researchers at the University of Colorado, Boulder and at the National Renewable Energy Laboratory. After establishing our computational proof-of-concept, we collectively used the new design rules to select an improved system for energy pooling. This consisted of rhodamine 6G and stilbene-420. These molecules were fabricated into a thin film, and the maximum internal quantum yield was measured to be 36% under sufficiently high intensity light. To further increase the efficiency of energy pooling, encapsulation within optical cavities was considered as a way of changing the rate of processes characterized by electric dipole-dipole coupling. This was carried out using a combination of classical electromagnetism, quantum electrodynamics, and perturbation theory. It was found that, in the near field, if the distance of the energy transfer is smaller than the distance from the energy transfer site and the cavity wall, then the electric dipole-dipole coupling tensor is not influenced by the cavity environment and the rates of energy transfer processes are the same as those in free space. Any increase in energy transfer efficiencies that are experimentally measured must therefore be caused by changing the rate of light absorption and emission. This is an important finding because earlier, less rigorous studies had concluded otherwise. It has been previously demonstrated that an optical cavity can be used to inhibit the spontaneous emission of atoms or molecules placed within it. This too was examined as a possible means of increasing energy pooling efficiency. Using first-principles methods, quantum electrodynamics, perturbation theory, and a kinetic model, the efficiency of energy pooling upconversion within a tuned rectangular cavity was found to be significantly larger than in free space. A model system with a free-space energy pooling upconversion efficiency of 23% was found to increase to 47% when placed in a tuned rectangular cavity.

Towards explaining the health impacts of residential energy efficiency interventions - A realist review. Part 1: Pathways.

PubMed

Willand, Nicola; Ridley, Ian; Maller, Cecily

2015-05-01

This paper is Part 1 of a realist review that tries to explain the impacts of residential energy efficiency interventions (REEIs) on householder health. According to recent systematic reviews residential energy efficiency interventions may benefit health. It is argued that home energy improvement are complex interventions and that a better understanding of the latent mechanisms and contextual issues that may shape the outcome of interventions is needed for effective intervention design. This realist review synthesises the results of 28 energy efficiency improvement programmes. This first part provides a review of the explanatory factors of the three key pathways, namely warmth in the home, affordability of fuel and psycho-social factors, and the pitfall of inadequate indoor air quality. The review revealed that REEIs improved winter warmth and lowered relative humidity with benefits for cardiovascular and respiratory health. In addition, residential energy efficiency improvements consolidated the meaning of the home as a safe haven, strengthened the householder's perceived autonomy and enhanced social status. Although satisfaction with the home proved to be an important explanation for positive mental health outcomes, financial considerations seemed to have played a secondary role. Evidence for negative impacts was rare but the risk should not be dismissed. Comprehensive refurbishments were not necessarily more effective than thermal retrofits or upgrades. A common protocol for the quantitative and qualitative evaluation of interventions would facilitate the synthesis of future studies. Householder and contextual influences are addressed in Part 2. Copyright © 2015 Elsevier Ltd. All rights reserved.

An Assessment Model for Energy Efficiency Program Planning in Electric Utilities: Case of the Pacific of Northwest U.S.A

NASA Astrophysics Data System (ADS)

Iskin, Ibrahim

Energy efficiency stands out with its potential to address a number of challenges that today's electric utilities face, including increasing and changing electricity demand, shrinking operating capacity, and decreasing system reliability and flexibility. Being the least cost and least risky alternative, the share of energy efficiency programs in utilities' energy portfolios has been on the rise since the 1980s, and their increasing importance is expected to continue in the future. Despite holding great promise, the ability to determine and invest in only the most promising program alternatives plays a key role in the successful use of energy efficiency as a utility-wide resource. This issue becomes even more significant considering the availability of a vast number of potential energy efficiency programs, the rapidly changing business environment, and the existence of multiple stakeholders. This dissertation introduces hierarchical decision modeling as the framework for energy efficiency program planning in electric utilities. The model focuses on the assessment of emerging energy efficiency programs and proposes to bridge the gap between technology screening and cost/benefit evaluation practices. This approach is expected to identify emerging technology alternatives which have the highest potential to pass cost/benefit ratio testing procedures and contribute to the effectiveness of decision practices in energy efficiency program planning. The model also incorporates rank order analysis and sensitivity analysis for testing the robustness of results from different stakeholder perspectives and future uncertainties in an attempt to enable more informed decision-making practices. The model was applied to the case of 13 high priority emerging energy efficiency program alternatives identified in the Pacific Northwest, U.S.A. The results of this study reveal that energy savings potential is the most important program management consideration in selecting emerging energy efficiency programs. Market dissemination potential and program development and implementation potential are the second and third most important, whereas ancillary benefits potential is the least important program management consideration. The results imply that program value considerations, comprised of energy savings potential and ancillary benefits potential; and program feasibility considerations, comprised of program development and implementation potential and market dissemination potential, have almost equal impacts on assessment of emerging energy efficiency programs. Considering the overwhelming number of value-focused studies and the few feasibility-focused studies in the literature, this finding clearly shows that feasibility-focused studies are greatly understudied. The hierarchical decision model developed in this dissertation is generalizable. Thus, other utilities or power systems can adopt the research steps employed in this study as guidelines and conduct similar assessment studies on emerging energy efficiency programs of their interest.

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

Cramton, Karen; Peters, Katherine

With $10 million in funding from the U.S. Department of Energy's (DOE) Better Buildings Neighborhood Program, the NH Better Buildings program was established as an initiative that initially empowered the three “Beacon Communities” of Berlin, Nashua and Plymouth to achieve transformative energy savings and reductions in fossil fuel use and greenhouse gases through deep energy retrofits and complementary sustainable energy solutions. The program also enabled those Communities to provide leadership to other communities around the state as “beacons” of energy efficiency. The goal of the program was to reduce energy use by a minimum of 15% through energy efficiency upgradesmore » in residential and commercial buildings in the communities. The program expanded statewide in April 2012 by issuing a competitive solicitation for additional commercial projects non-profit, and municipal energy efficiency projects from any community in the state, and a partnership with the state’s utility-run, ratepayer-funded residential Home Performance with ENERGY STAR® (HPwES) program. The NH Better Buildings program was administered by the New Hampshire Office of Energy and Planning (OEP) and managed by the NH Community Development Finance Authority (CDFA). The program started in July 2010 and the last projects funded with American Reinvestment and Recovery Act (ARRA) funds were completed in August 2013. The program will continue after the American Recovery and Reinvestment Act program period as a Revolving Loan Fund, enabling low-interest financing for deep energy retrofits into the future.« less

A Novel Addressing Scheme for PMIPv6 Based Global IP-WSNs

PubMed Central

Islam, Md. Motaharul; Huh, Eui-Nam

2011-01-01

IP based Wireless Sensor Networks (IP-WSNs) are being used in healthcare, home automation, industrial control and agricultural monitoring. In most of these applications global addressing of individual IP-WSN nodes and layer-three routing for mobility enabled IP-WSN with special attention to reliability, energy efficiency and end to end delay minimization are a few of the major issues to be addressed. Most of the routing protocols in WSN are based on layer-two approaches. For reliability and end to end communication enhancement the necessity of layer-three routing for IP-WSNs is generating significant attention among the research community, but due to the hurdle of maintaining routing state and other communication overhead, it was not possible to introduce a layer-three routing protocol for IP-WSNs. To address this issue we propose in this paper a global addressing scheme and layer-three based hierarchical routing protocol. The proposed addressing and routing approach focuses on all the above mentioned issues. Simulation results show that the proposed addressing and routing approach significantly enhances the reliability, energy efficiency and end to end delay minimization. We also present architecture, message formats and different routing scenarios in this paper. PMID:22164084

A novel addressing scheme for PMIPv6 based global IP-WSNs.

PubMed

Islam, Md Motaharul; Huh, Eui-Nam

2011-01-01

IP based Wireless Sensor Networks (IP-WSNs) are being used in healthcare, home automation, industrial control and agricultural monitoring. In most of these applications global addressing of individual IP-WSN nodes and layer-three routing for mobility enabled IP-WSN with special attention to reliability, energy efficiency and end to end delay minimization are a few of the major issues to be addressed. Most of the routing protocols in WSN are based on layer-two approaches. For reliability and end to end communication enhancement the necessity of layer-three routing for IP-WSNs is generating significant attention among the research community, but due to the hurdle of maintaining routing state and other communication overhead, it was not possible to introduce a layer-three routing protocol for IP-WSNs. To address this issue we propose in this paper a global addressing scheme and layer-three based hierarchical routing protocol. The proposed addressing and routing approach focuses on all the above mentioned issues. Simulation results show that the proposed addressing and routing approach significantly enhances the reliability, energy efficiency and end to end delay minimization. We also present architecture, message formats and different routing scenarios in this paper.

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

Hameed, Abdul; Khoshkbarforoushha, Alireza; Ranjan, Rajiv

In a cloud computing paradigm, energy efficient allocation of different virtualized ICT resources (servers, storage disks, and networks, and the like) is a complex problem due to the presence of heterogeneous application (e.g., content delivery networks, MapReduce, web applications, and the like) workloads having contentious allocation requirements in terms of ICT resource capacities (e.g., network bandwidth, processing speed, response time, etc.). Several recent papers have tried to address the issue of improving energy efficiency in allocating cloud resources to applications with varying degree of success. However, to the best of our knowledge there is no published literature on this subjectmore » that clearly articulates the research problem and provides research taxonomy for succinct classification of existing techniques. Hence, the main aim of this paper is to identify open challenges associated with energy efficient resource allocation. In this regard, the study, first, outlines the problem and existing hardware and software-based techniques available for this purpose. Furthermore, available techniques already presented in the literature are summarized based on the energy-efficient research dimension taxonomy. The advantages and disadvantages of the existing techniques are comprehensively analyzed against the proposed research dimension taxonomy namely: resource adaption policy, objective function, allocation method, allocation operation, and interoperability.« less

Enhanced Charge Separation and FRET at Heterojunctions between Semiconductor Nanoparticles and Conducting Polymer Nanofibers for Efficient Solar Light Harvesting

PubMed Central

Sardar, Samim; Kar, Prasenjit; Remita, Hynd; Liu, Bo; Lemmens, Peter; Kumar Pal, Samir; Ghosh, Srabanti

2015-01-01

Energy harvesting from solar light employing nanostructured materials offer an economic way to resolve energy and environmental issues. We have developed an efficient light harvesting heterostructure based on poly(diphenylbutadiyne) (PDPB) nanofibers and ZnO nanoparticles (NPs) via a solution phase synthetic route. ZnO NPs (~20 nm) were homogeneously loaded onto the PDPB nanofibers as evident from several analytical and spectroscopic techniques. The photoinduced electron transfer from PDPB nanofibers to ZnO NPs has been confirmed by steady state and picosecond-resolved photoluminescence studies. The co-sensitization for multiple photon harvesting (with different energies) at the heterojunction has been achieved via a systematic extension of conjugation from monomeric to polymeric diphenyl butadiyne moiety in the proximity of the ZnO NPs. On the other hand, energy transfer from the surface defects of ZnO NPs (~5 nm) to PDPB nanofibers through Förster Resonance Energy Transfer (FRET) confirms the close proximity with molecular resolution. The manifestation of efficient charge separation has been realized with ~5 fold increase in photocatalytic degradation of organic pollutants in comparison to polymer nanofibers counterpart under visible light irradiation. Our results provide a novel approach for the development of nanoheterojunctions for efficient light harvesting which will be helpful in designing future solar devices. PMID:26611253

Experimental investigation of efficient locomotion of underwater snake robots for lateral undulation and eel-like motion patterns.

PubMed

Kelasidi, Eleni; Liljebäck, Pål; Pettersen, Kristin Y; Gravdahl, Jan T

2015-01-01

Underwater snake robots offer many interesting capabilities for underwater operations. The long and slender structure of such robots provide superior capabilities for access through narrow openings and within confined areas. This is interesting for inspection and monitoring operations, for instance within the subsea oil and gas industry and within marine archeology. In addition, underwater snake robots can provide both inspection and intervention capabilities and are thus interesting candidates for the next generation inspection and intervention AUVs. Furthermore, bioinspired locomotion through oscillatory gaits, like lateral undulation and eel-like motion, is interesting from an energy efficiency point of view. Increasing the motion efficiency in terms of the achieved forward speed by improving the method of propulsion is a key issue for underwater robots. Moreover, energy efficiency is one of the main challenges for long-term autonomy of these systems. In this study, we will consider both these two aspects of efficiency. This paper considers the energy efficiency of swimming snake robots by presenting and experimentally investigating fundamental properties of the velocity and the power consumption of an underwater snake robot for both lateral undulation and eel-like motion patterns. In particular, we investigate the relationship between the parameters of the gait patterns, the forward velocity and the energy consumption for different motion patterns. The simulation and experimental results are seen to support the theoretical findings.

Energetic and environmental assessment of thermochemical and biochemical ways for producing energy from agricultural solid residues: Coffee Cut-Stems case.

PubMed

García, Carlos A; Peña, Álvaro; Betancourt, Ramiro; Cardona, Carlos A

2018-06-15

Forest residues are an important source of biomass. Among these, Coffee Cut-Stems (CCS) are an abundant wood waste in Colombia obtained from coffee crops renovation. However, only low quantities of these residues are used directly in combustion processes for heating and cooking in coffee farms where their energy efficiency is very low. In the present work, an energy and environmental assessment of two bioenergy production processes (ethanol fermentation and gasification) using CCS as raw material was performed. Biomass gasification seems to be the most promising thermochemical method for bioenergy production whereas, ethanol fermentation is a widely studied biochemical method to produce biofuels. Experimental runs of the CCS gasification were carried out and the synthesis gas composition was monitored. Prior to the fermentation process, a treatment of the CCS is required from which sugar content was determined and then, in the fermentation process, the ethanol yield was calculated. Both processes were simulated in order to obtain the mass and energy balance that are used to assess the energy efficiency and the potential environmental impact (PEI). Moderate high energy efficiency and low environmental impacts were obtained from the CCS gasification. In contrast, high environmental impacts in different categories and low energy efficiencies were calculated from the ethanolic fermentation. Biomass gasification seems to be the most promising technology for the use of Coffee Cut-Stems with high energy yields and low environmental issues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Energy and environmental policy in a period of transition

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

Stalon, C.G.

1995-12-31

This paper discusses governance aspects of electric industry restructuring. The creation and preservation of a governance system to ensure reliable and efficient trades within interconnected and independent trading areas is the main topic. The closely related issue of defining and imposing responsibilities on non-utility generators is also discussed in detail. It is recommended that the Federal Energy Regulatory Commission promote private governance of interconnections. 1 tab.

Influence of the chemical surface structure on the nanoscale friction in plasma nitrided and post-oxidized ferrous alloy

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

Freislebem, Márcia; Menezes, Caren M.; Cemin, Felipe

2014-09-15

Friction is a ubiquitous phenomenon in everyday activities spanning from vehicles where efficient brakes are mandatory up to mechanical devices where its minimum effects are pursued for energy efficiency issues. Recently, theoretical models succeed correlating the friction behavior with energy transference via phonons between sliding surfaces. Therefore, considering that the energy losses by friction are prompted through phonons, the chemical surface structure between sliding surfaces is very important to determine the friction phenomenon. In this work, we address the issue of friction between a conical diamond tip sliding on different functionalized flat steel surfaces by focusing the influence of themore » chemical bonds in the outermost layers on the sliding resistance. This geometry allows probing the coupling of the sharp tip with terminator species on the top and underneath material surface at in-depth friction measurements from 20 to 200 nm. Experimentally, the friction coefficient decreases when nitrogen atoms are substituted for oxygen in the iron network. This effect is interpreted as due to energy losses through phonons whilst lower vibrational frequency excitation modes imply lower friction coefficients and a more accurate adjustment is obtained when a theoretical model with longitudinal adsorbate vibration is used.« less

Watershed Restoration Project

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

Julie Thompson; Betsy Macfarlan

2007-09-27

In 2003, the U.S. Department of Energy issued the Eastern Nevada Landscape Coalition (ENLC) funding to implement ecological restoration in Gleason Creek and Smith Valley Watersheds. This project was made possible by congressionally directed funding that was provided through the US Department of Energy, Energy Efficiency and Renewable Energy, Office of the Biomass Program. The Ely District Bureau of Land Management (Ely BLM) manages these watersheds and considers them priority areas within the Ely BLM district. These three entities collaborated to address the issues and concerns of Gleason Creek and Smith Valley and prepared a restoration plan to improve themore » watersheds’ ecological health and resiliency. The restoration process began with watershed-scale vegetation assessments and state and transition models to focus on restoration sites. Design and implementation of restoration treatments ensued and were completed in January 2007. This report describes the restoration process ENLC undertook from planning to implementation of two watersheds in semi-arid Eastern Nevada.« less

Evaluation of gasification and novel thermal processes for the treatment of municipal solid waste

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

Niessen, W.R.; Marks, C.H.; Sommerlad, R.E.

1996-08-01

This report identifies seven developers whose gasification technologies can be used to treat the organic constituents of municipal solid waste: Energy Products of Idaho; TPS Termiska Processor AB; Proler International Corporation; Thermoselect Inc.; Battelle; Pedco Incorporated; and ThermoChem, Incorporated. Their processes recover heat directly, produce a fuel product, or produce a feedstock for chemical processes. The technologies are on the brink of commercial availability. This report evaluates, for each technology, several kinds of issues. Technical considerations were material balance, energy balance, plant thermal efficiency, and effect of feedstock contaminants. Environmental considerations were the regulatory context, and such things as composition,more » mass rate, and treatability of pollutants. Business issues were related to likelihood of commercialization. Finally, cost and economic issues such as capital and operating costs, and the refuse-derived fuel preparation and energy c onversion costs, were considered. The final section of the report reviews and summarizes the information gathered during the study.« less

Alternative Uses of Highway Right-of-Way : Accommodating Renewable Energy Technologies and Alternative Fuel Facilities

DOT National Transportation Integrated Search

2012-01-31

In recent years, the U.S. Department of Transportation (U.S. DOT) has sought to better understand global climate change and the transportation sectors effects on the issue, and vice versa. The Safe, Accountable, Flexible, Efficient Transportation ...

Higher Efficiency for Quasi-Solid State Dye Sensitized Solar Cells Under Low Light Irradiance

NASA Astrophysics Data System (ADS)

Desilva, Ajith; Bandara, T. M. W. J.; Fernado, H. D. N. S.; Fernando, P. S. L.; Dissanayake, M. A. K. L.; Jayasundara, W. J. M. J. S. R.; Furlani, M.; Mellander, B.-E.

2014-03-01

Dye-sensitized solar cells (DSSCs), lower cost solar energy conversion devices are alternative green energy source. The liquid based electrolyte DSSCs have higher efficiencies with many practical issues while the quasi-solid-state DSSCs resolve the key problems but efficiencies are relatively low. Polyacrylonitrile (PAN) based gel polymer electrolytes were fabricated as DSSCs by incorporating ethylene carbonate and propylene carbonate plasticizers and tetrapropylammonium iodide salt. A thin layer of electrolyte was sandwiched between the TiO2 anode (sensitized with N719 dye) and the Pt counter electrode. The electrolyte had an ionic conductivity of 2.6 mS/cm at 25 degrees of Celsius. DSSCs incorporating this gel electrolyte revealed Vsc circuit, Jsc, fill factor (FF) and efficiency values of 0.71 V, 11.8 mA, 51 percent and 4.2 percent respectively under 1 sun irradiation. The efficiency of the cell increased with decreasing solar irradiance achieving up to 10 percent efficiency and 80 percent FF at low irradiance values. This work uncovers that quasi-solid state DSSCs can reach efficiencies close to that of liquid electrolytes based cells.

Energy performance assessment of virtualization technologies using small environmental monitoring sensors.

PubMed

Liu, Lu; Masfary, Osama; Antonopoulos, Nick

2012-01-01

The increasing trends of electrical consumption within data centres are a growing concern for business owners as they are quickly becoming a large fraction of the total cost of ownership. Ultra small sensors could be deployed within a data centre to monitor environmental factors to lower the electrical costs and improve the energy efficiency. Since servers and air conditioners represent the top users of electrical power in the data centre, this research sets out to explore methods from each subsystem of the data centre as part of an overall energy efficient solution. In this paper, we investigate the current trends of Green IT awareness and how the deployment of small environmental sensors and Site Infrastructure equipment optimization techniques which can offer a solution to a global issue by reducing carbon emissions.

Second derivatives for approximate spin projection methods

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

Thompson, Lee M.; Hratchian, Hrant P., E-mail: hhratchian@ucmerced.edu

2015-02-07

The use of broken-symmetry electronic structure methods is required in order to obtain correct behavior of electronically strained open-shell systems, such as transition states, biradicals, and transition metals. This approach often has issues with spin contamination, which can lead to significant errors in predicted energies, geometries, and properties. Approximate projection schemes are able to correct for spin contamination and can often yield improved results. To fully make use of these methods and to carry out exploration of the potential energy surface, it is desirable to develop an efficient second energy derivative theory. In this paper, we formulate the analytical secondmore » derivatives for the Yamaguchi approximate projection scheme, building on recent work that has yielded an efficient implementation of the analytical first derivatives.« less

An energy efficient distance-aware routing algorithm with multiple mobile sinks for wireless sensor networks.

PubMed

Wang, Jin; Li, Bin; Xia, Feng; Kim, Chang-Seob; Kim, Jeong-Uk

2014-08-18

Traffic patterns in wireless sensor networks (WSNs) usually follow a many-to-one model. Sensor nodes close to static sinks will deplete their limited energy more rapidly than other sensors, since they will have more data to forward during multihop transmission. This will cause network partition, isolated nodes and much shortened network lifetime. Thus, how to balance energy consumption for sensor nodes is an important research issue. In recent years, exploiting sink mobility technology in WSNs has attracted much research attention because it can not only improve energy efficiency, but prolong network lifetime. In this paper, we propose an energy efficient distance-aware routing algorithm with multiple mobile sink for WSNs, where sink nodes will move with a certain speed along the network boundary to collect monitored data. We study the influence of multiple mobile sink nodes on energy consumption and network lifetime, and we mainly focus on the selection of mobile sink node number and the selection of parking positions, as well as their impact on performance metrics above. We can see that both mobile sink node number and the selection of parking position have important influence on network performance. Simulation results show that our proposed routing algorithm has better performance than traditional routing ones in terms of energy consumption.

Analysis of environmental impacts of renewable energy on the Moroccan electricity sector: A System Dynamics approach

NASA Astrophysics Data System (ADS)

Chentouf, M.; Allouch, M.

2018-05-01

Producing electricity at an affordable price while taking into account environmental concerns has become a major challenge in Morocco. Moreover, the technical and financial issues related to renewable electricity plants are still hindering their efficient integration in the country. In fact, the energy sector (both electricity and heat) accounted for more than half of all Greenhouse Gases (GHG) emissions in the kingdom due to the major reliance on fossil fuels for answering the growing local demand. The key strategies to alleviate this critical situation include the integration of more renewable energies in the total energy mix and the enhancement of energy efficiency measures in different sectors. This paper strives to (1) evaluate the potential of carbon dioxide mitigation in Moroccan electricity sector following the actual and projected strategies and (2) highlight the policy schemes to be taken in order to achieve the ambitious carbon dioxide mitigation targets in the mid-term. A system dynamics model was built in order to simulate different scenarios of carbon dioxide mitigation policies up to 2030. The results shows that the achievement of renewable energies projects by 2030 could save 228.143 MtCO2 between 2020 and 2030 and an additional 18.127 MtCO2 could be avoided in the same period by enhancing energy efficiency measures.

An Energy Efficient Distance-Aware Routing Algorithm with Multiple Mobile Sinks for Wireless Sensor Networks

PubMed Central

Wang, Jin; Li, Bin; Xia, Feng; Kim, Chang-Seob; Kim, Jeong-Uk

2014-01-01

Traffic patterns in wireless sensor networks (WSNs) usually follow a many-to-one model. Sensor nodes close to static sinks will deplete their limited energy more rapidly than other sensors, since they will have more data to forward during multihop transmission. This will cause network partition, isolated nodes and much shortened network lifetime. Thus, how to balance energy consumption for sensor nodes is an important research issue. In recent years, exploiting sink mobility technology in WSNs has attracted much research attention because it can not only improve energy efficiency, but prolong network lifetime. In this paper, we propose an energy efficient distance-aware routing algorithm with multiple mobile sink for WSNs, where sink nodes will move with a certain speed along the network boundary to collect monitored data. We study the influence of multiple mobile sink nodes on energy consumption and network lifetime, and we mainly focus on the selection of mobile sink node number and the selection of parking positions, as well as their impact on performance metrics above. We can see that both mobile sink node number and the selection of parking position have important influence on network performance. Simulation results show that our proposed routing algorithm has better performance than traditional routing ones in terms of energy consumption. PMID:25196015

An energy-efficient and compact clustering scheme with temporary support nodes for cognitive radio sensor networks.

PubMed

Salim, Shelly; Moh, Sangman; Choi, Dongmin; Chung, Ilyong

2014-08-11

A cognitive radio sensor network (CRSN) is a wireless sensor network whose sensor nodes are equipped with cognitive radio capability. Clustering is one of the most challenging issues in CRSNs, as all sensor nodes, including the cluster head, have to use the same frequency band in order to form a cluster. However, due to the nature of heterogeneous channels in cognitive radio, it is difficult for sensor nodes to find a cluster head. This paper proposes a novel energy-efficient and compact clustering scheme named clustering with temporary support nodes (CENTRE). CENTRE efficiently achieves a compact cluster formation by adopting two-phase cluster formation with fixed duration. By introducing a novel concept of temporary support nodes to improve the cluster formation, the proposed scheme enables sensor nodes in a network to find a cluster head efficiently. The performance study shows that not only is the clustering process efficient and compact but it also results in remarkable energy savings that prolong the overall network lifetime. In addition, the proposed scheme decreases both the clustering overhead and the average distance between cluster heads and their members.

An Energy-Efficient and Compact Clustering Scheme with Temporary Support Nodes for Cognitive Radio Sensor Networks

PubMed Central

Salim, Shelly; Moh, Sangman; Choi, Dongmin; Chung, Ilyong

2014-01-01

A cognitive radio sensor network (CRSN) is a wireless sensor network whose sensor nodes are equipped with cognitive radio capability. Clustering is one of the most challenging issues in CRSNs, as all sensor nodes, including the cluster head, have to use the same frequency band in order to form a cluster. However, due to the nature of heterogeneous channels in cognitive radio, it is difficult for sensor nodes to find a cluster head. This paper proposes a novel energy-efficient and compact clustering scheme named clustering with temporary support nodes (CENTRE). CENTRE efficiently achieves a compact cluster formation by adopting two-phase cluster formation with fixed duration. By introducing a novel concept of temporary support nodes to improve the cluster formation, the proposed scheme enables sensor nodes in a network to find a cluster head efficiently. The performance study shows that not only is the clustering process efficient and compact but it also results in remarkable energy savings that prolong the overall network lifetime. In addition, the proposed scheme decreases both the clustering overhead and the average distance between cluster heads and their members. PMID:25116905

Bifacial dye-sensitized solar cells: A strategy to enhance overall efficiency based on transparent polyaniline electrode

PubMed Central

Wu, Jihuai; Li, Yan; Tang, Qunwei; Yue, Gentian; Lin, Jianming; Huang, Miaoliang; Meng, Lijian

2014-01-01

Dye-sensitized solar cell (DSSC) is a promising solution to global energy and environmental problems because of its clean, low-cost, high efficiency, good durability, and easy fabrication. However, enhancing the efficiency of the DSSC still is an important issue. Here we devise a bifacial DSSC based on a transparent polyaniline (PANI) counter electrode (CE). Owing to the sunlight irradiation simultaneously from the front and the rear sides, more dye molecules are excited and more carriers are generated, which results in the enhancement of short-circuit current density and therefore overall conversion efficiency. The photoelectric properties of PANI can be improved by modifying with 4-aminothiophenol (4-ATP). The bifacial DSSC with 4-ATP/PANI CE achieves a light-to-electric energy conversion efficiency of 8.35%, which is increased by ~24.6% compared to the DSSC irradiated from the front only. This new concept along with promising results provides a new approach for enhancing the photovoltaic performances of solar cells. PMID:24504117

Mathematical analysis and coordinated current allocation control in battery power module systems

NASA Astrophysics Data System (ADS)

Han, Weiji; Zhang, Liang

2017-12-01

As the major energy storage device and power supply source in numerous energy applications, such as solar panels, wind plants, and electric vehicles, battery systems often face the issue of charge imbalance among battery cells/modules, which can accelerate battery degradation, cause more energy loss, and even incur fire hazard. To tackle this issue, various circuit designs have been developed to enable charge equalization among battery cells/modules. Recently, the battery power module (BPM) design has emerged to be one of the promising solutions for its capability of independent control of individual battery cells/modules. In this paper, we propose a new current allocation method based on charging/discharging space (CDS) for performance control in BPM systems. Based on the proposed method, the properties of CDS-based current allocation with constant parameters are analyzed. Then, real-time external total power requirement is taken into account and an algorithm is developed for coordinated system performance control. By choosing appropriate control parameters, the desired system performance can be achieved by coordinating the module charge balance and total power efficiency. Besides, the proposed algorithm has complete analytical solutions, and thus is very computationally efficient. Finally, the efficacy of the proposed algorithm is demonstrated using simulations.

Energy and fuels from electrochemical interfaces

NASA Astrophysics Data System (ADS)

Stamenkovic, Vojislav R.; Strmcnik, Dusan; Lopes, Pietro P.; Markovic, Nenad M.

2017-01-01

Advances in electrocatalysis at solid-liquid interfaces are vital for driving the technological innovations that are needed to deliver reliable, affordable and environmentally friendly energy. Here, we highlight the key achievements in the development of new materials for efficient hydrogen and oxygen production in electrolysers and, in reverse, their use in fuel cells. A key issue addressed here is the degree to which the fundamental understanding of the synergy between covalent and non-covalent interactions can form the basis for any predictive ability in tailor-making real-world catalysts. Common descriptors such as the substrate-hydroxide binding energy and the interactions in the double layer between hydroxide-oxides and H---OH are found to control individual parts of the hydrogen and oxygen electrochemistry that govern the efficiency of water-based energy conversion and storage systems. Links between aqueous- and organic-based environments are also established, encouraging the 'fuel cell' and 'battery' communities to move forward together.

Mechanical Computing Redux: Limitations at the Nanoscale

NASA Astrophysics Data System (ADS)

Liu, Tsu-Jae King

2014-03-01

Technology solutions for overcoming the energy efficiency limits of nanoscale complementary metal oxide semiconductor (CMOS) technology ultimately will be needed in order to address the growing issue of integrated-circuit chip power density. Off-state leakage current sets a fundamental lower limit in energy per operation for any voltage-level-based digital logic implemented with transistors (CMOS and beyond), which leads to practical limits for device density (i.e. cost) and operating frequency (i.e. system performance). Mechanical switches have zero off-state leakag and hence can overcome this fundamental limit. Contact adhesive force sets a lower limit for the switching energy of a mechanical switch, however, and also directly impacts its performance. This paper will review recent progress toward the development of nano-electro-mechanical relay technology and discuss remaining challenges for realizing the promise of mechanical computing for ultra-low-power computing. Supported by the Center for Energy Efficient Electronics Science (NSF Award 0939514).

Advances in Household Appliances- A Review

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

Bansal, Pradeep; Vineyard, Edward Allan; Abdelaziz, Omar

2011-01-01

An overview of options and potential barriers and risks for reducing the energy consumption, peak demand, and emissions for seven key energy consuming residential products (refrigerator-freezers, dishwashers, clothes washers, clothes dryers, electric ovens, gas ovens and microwave ovens) is presented. The paper primarily concentrates on the potential energy savings from the use of advanced technologies in appliances for the U.S. market. The significance and usefulness of each technology was evaluated in order to prioritize the R&D needs to improve energy efficiency of appliances in view of energy savings, cost, and complexity. The paper provides a snapshot of the future R&Dmore » needs for each of the technologies along with the associated barriers. Although significant energy savings may be achieved, one of the major barriers in most cases is high first cost. One way of addressing this issue and promoting the introduction of new technologies is to level the playing field for all manufacturers by establishing Minimum Energy Performance Standards (MEPS) which are not cost prohibitive and promoting energy efficient products through incentives to both manufacturers and consumers.« less

Market and policy barriers to deployment of energy storage

DOE PAGES

Sioshansi, Ramteen; Denholm, Paul; Jenkin, Thomas

2012-04-01

There has recently been resurgent interest in energy storage, due to a number of developments in the electricity industry. Despite this interest, very little storage, beyond some small demonstration projects, has been deployed recently. While technical issues, such as cost, device efficiency, and other technical characteristics are often listed as barriers to storage, there are a number of non-technical and policy-related issues. This paper surveys some of these main barriers and proposes some potential research and policy steps that can help address them. Furthermore, while the discussion is focused on the United States, a number of the findings and observationsmore » may be more broadly applicable.« less

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

Gibson-Grant, Amy

Postwave tracking study for the Energy Efficiency Adult Campaign This study serves as measure of key metrics among the campaign’s target audience, homeowners age 25+. Key measures include: Awareness of messages relating to the broad issue; Recognition of the PSAs; Relevant attitudes, including interest, ease of taking energy efficient steps, and likelihood to act; Relevant knowledge, including knowledge of light bulb alternatives and energy efficient options; and Relevant behaviors, including specific energy-saving behaviors mentioned within the PSAs. Wave 1: May 27 – June 7, 2011 Wave 2: May 29 – June 8, 2012 Wave 3: May 29 – June 19,more » 2014 General market sample of adults 25+ who own their homes W1 sample: n = 704; W2: n=701; W3: n=806 Online Survey Panel Methodology Study was fielded by Lightspeed Research among their survey panel. Sample is US Census representative of US homeowners by race/ethnicity, income, age, region, and family status. At least 30% of respondents were required to have not updated major appliances in their home in the past 5 years (dishwasher, stove, refrigerator, washer, or dryer).« less

Development of Energy Efficient Clustering Protocol in Wireless Sensor Network Using Neuro-Fuzzy Approach.

PubMed

Julie, E Golden; Selvi, S Tamil

2016-01-01

Wireless sensor networks (WSNs) consist of sensor nodes with limited processing capability and limited nonrechargeable battery power. Energy consumption in WSN is a significant issue in networks for improving network lifetime. It is essential to develop an energy aware clustering protocol in WSN to reduce energy consumption for increasing network lifetime. In this paper, a neuro-fuzzy energy aware clustering scheme (NFEACS) is proposed to form optimum and energy aware clusters. NFEACS consists of two parts: fuzzy subsystem and neural network system that achieved energy efficiency in forming clusters and cluster heads in WSN. NFEACS used neural network that provides effective training set related to energy and received signal strength of all nodes to estimate the expected energy for tentative cluster heads. Sensor nodes with higher energy are trained with center location of base station to select energy aware cluster heads. Fuzzy rule is used in fuzzy logic part that inputs to form clusters. NFEACS is designed for WSN handling mobility of node. The proposed scheme NFEACS is compared with related clustering schemes, cluster-head election mechanism using fuzzy logic, and energy aware fuzzy unequal clustering. The experiment results show that NFEACS performs better than the other related schemes.

Development of Energy Efficient Clustering Protocol in Wireless Sensor Network Using Neuro-Fuzzy Approach

PubMed Central

Julie, E. Golden; Selvi, S. Tamil

2016-01-01

Wireless sensor networks (WSNs) consist of sensor nodes with limited processing capability and limited nonrechargeable battery power. Energy consumption in WSN is a significant issue in networks for improving network lifetime. It is essential to develop an energy aware clustering protocol in WSN to reduce energy consumption for increasing network lifetime. In this paper, a neuro-fuzzy energy aware clustering scheme (NFEACS) is proposed to form optimum and energy aware clusters. NFEACS consists of two parts: fuzzy subsystem and neural network system that achieved energy efficiency in forming clusters and cluster heads in WSN. NFEACS used neural network that provides effective training set related to energy and received signal strength of all nodes to estimate the expected energy for tentative cluster heads. Sensor nodes with higher energy are trained with center location of base station to select energy aware cluster heads. Fuzzy rule is used in fuzzy logic part that inputs to form clusters. NFEACS is designed for WSN handling mobility of node. The proposed scheme NFEACS is compared with related clustering schemes, cluster-head election mechanism using fuzzy logic, and energy aware fuzzy unequal clustering. The experiment results show that NFEACS performs better than the other related schemes. PMID:26881269

Role of Friction in Materials Selection for Automotive Applications

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

Blau, Peter Julian

This is an invited article for a special issue of the ASM International monthly magazine that concerns "Automotive Materials and Applications." The article itself overviews frictional considerations in material selection for automobiles. It discusses implications for energy efficiency (engine friction) and safety (brakes) among other topics.

Sustainable IT and IT for Sustainability

NASA Astrophysics Data System (ADS)

Liu, Zhenhua

Energy and sustainability have become one of the most critical issues of our generation. While the abundant potential of renewable energy such as solar and wind provides a real opportunity for sustainability, their intermittency and uncertainty present a daunting operating challenge. This thesis aims to develop analytical models, deployable algorithms, and real systems to enable efficient integration of renewable energy into complex distributed systems with limited information. The first thrust of the thesis is to make IT systems more sustainable by facilitating the integration of renewable energy into these systems. IT represents the fastest growing sectors in energy usage and greenhouse gas pollution. Over the last decade there are dramatic improvements in the energy efficiency of IT systems, but the efficiency improvements do not necessarily lead to reduction in energy consumption because more servers are demanded. Further, little effort has been put in making IT more sustainable, and most of the improvements are from improved "engineering" rather than improved "algorithms". In contrast, my work focuses on developing algorithms with rigorous theoretical analysis that improve the sustainability of IT. In particular, this thesis seeks to exploit the flexibilities of cloud workloads both (i) in time by scheduling delay-tolerant workloads and (ii) in space by routing requests to geographically diverse data centers. These opportunities allow data centers to adaptively respond to renewable availability, varying cooling efficiency, and fluctuating energy prices, while still meeting performance requirements. The design of the enabling algorithms is however very challenging because of limited information, non-smooth objective functions and the need for distributed control. Novel distributed algorithms are developed with theoretically provable guarantees to enable the "follow the renewables" routing. Moving from theory to practice, I helped HP design and implement industry's first Net-zero Energy Data Center. The second thrust of this thesis is to use IT systems to improve the sustainability and efficiency of our energy infrastructure through data center demand response. The main challenges as we integrate more renewable sources to the existing power grid come from the fluctuation and unpredictability of renewable generation. Although energy storage and reserves can potentially solve the issues, they are very costly. One promising alternative is to make the cloud data centers demand responsive. The potential of such an approach is huge. To realize this potential, we need adaptive and distributed control of cloud data centers and new electricity market designs for distributed electricity resources. My work is progressing in both directions. In particular, I have designed online algorithms with theoretically guaranteed performance for data center operators to deal with uncertainties under popular demand response programs. Based on local control rules of customers, I have further designed new pricing schemes for demand response to align the interests of customers, utility companies, and the society to improve social welfare.

Architecture Capabilities to Improve Healthcare Environments

PubMed Central

Ebrahimi, Ali; Mardomi, Karim; Hassanpour Rahimabad, Kasra

2013-01-01

Background The physical environment of healthcare buildings has great importance in issues such as patient safety, functional efficiency, user satisfaction, healthcare outcomes, and energy and resources consumption. Objectives The present study assesses physical environments of Iranian healthcare buildings. Materials and Methods This study was performed using a descriptive-analytical method. Data collection was carried out via a written questionnaire. Results Based on the findings of this study, "functional efficiency", "user satisfaction", "environmental issues", "patient safety”, “accountability in incidents and disasters", and "flexibility" are regarded as the most issues in the country's hospitals. Also, none of the parameters is "without any problem" and has a "desirable status". Conclusions According to the responses, all of the healthcare buildings in this research had flaws in their physical environment, which require attention. Thus, it is necessary to review and pay more attention to the architecture of the country's healthcare buildings. PMID:24350145

Decontamination, decommissioning, and vendor advertorial issue, 2005

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

Agnihotri, Newal

2005-07-15

The focus of the July-August issue is on Decontamination, decommissioning, and vendor advertorials. Major interviews, articles and reports in this issue include: Increasing momentum, by Gary Taylor, Entergy Nuclear, Inc.; An acceptable investment, by Tom Chrisopher, Areva, Inc.; Fuel recycling for the U.S. and abroad, by Philippe Knoche, Areva, France; We're bullish on nuclear power, by Dan R. Keuter, Entergy Nuclear, Inc.; Ten key actions for decommissioning, by Lawrence E. Boing, Argonne National Laboratory; Safe, efficient and cost-effective decommissioning, by Dr. Claudio Pescatore and Torsten Eng, OECD Nuclear Energy Agency (NEA), France; and, Plant profile: SONGS decommissioning.

Emerging Regional Energy Security Issues China

DTIC Science & Technology

2009-09-29

moving toward European standards and taxation of least efficient vehicles www.csis.org | 7 China’s Energy Strategy - Clean Power Generation...Project Type of Contract Signature Date Estimated Value Contractor(s) Remarks Malaysian Amona (Main Contractor), Chinese COSL and CNOOC The first...infrastructure. List of Upstream Agreements Between Iran and China in Recent Years ** The original buyback contract w as signed betw een Malaysian Amona and

Status of research and development on photoelectrochemical hydrogen production in Korea

NASA Astrophysics Data System (ADS)

Kim, Jong Won; Lee, Jae S.; Baeg, Jin-Ook

2010-08-01

Conversion of solar energy into hydrogen is one of the most promising renewable energy technologies. Photocatalytic production of hydrogen from water, H2S and organic wastes using semiconductors is one of the potential strategies for converting the sunlight energy into chemical energy. Korea government paid great attention to the hydrogen economy and launched the HERC (Hydrogen Energy R&D Center) for supporting the R&D topics on hydrogen related technologies. The key issue for realizing the commercial application of solar water splitting hydrogen production technique is to find an efficient, stable and low-cost photocatalyst. Our research groups have continuously investigated to find oxide and composite photocatalysts for photoelectrochemical cell with high efficiency using computational design and synthesis method. But, fundamental research on semiconductor doping for band gap shifting and surface chemistry modification is still required. Various reaction media containing sacrificial agents should be developed to match with high activity photocatalysts to further improve the system efficiency. Water containing organic/inorganic waste and sea water are particularly suggested in the consideration that all these water sources are the most available water on the earth to the final commercial application of photocatalytic water splitting technique.

Task Order 20: Supercritical Carbon Dioxide Brayton Cycle Energy Conversion Study

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

Murray, Paul; Lindsay, Edward; McDowell, Michael

2015-04-23

AREVA Inc. developed this study for the US Department of Energy (DOE) office of Nuclear Energy (NE) in accordance with Task Order 20 Statement of Work (SOW) covering research and development activities for the Supercritical Carbon Dioxide (sCO2) Brayton Cycle energy conversion. The study addresses the conversion of sCO2 heat energy to electrical output by use of a Brayton Cycle system and focuses on the potential of a net efficiency increase via cycle recuperation and recompression stages. The study also addresses issues and study needed to advance development and implementation of a 10 MWe sCO2 demonstration project.

Advanced lighting guidelines: 1993. Final report

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

Eley, C.; Tolen, T.M.; Benya, J.R.

1993-12-31

The 1993 Advanced Lighting Guidelines document consists of twelve guidelines that provide an overview of specific lighting technologies and design application techniques utilizing energy-efficient lighting practice. Lighting Design Practice assesses energy-efficient lighting strategies, discusses lighting issues, and explains how to obtain quality lighting design and consulting services. Luminaires and Lighting Systems surveys luminaire equipment designed to take advantage of advanced technology lamp products and includes performance tables that allow for accurate estimation of luminaire light output and power input. The additional ten guidelines -- Computer-Aided Lighting Design, Energy-Efficient Fluorescent Ballasts, Full-Size Fluorescent Lamps, Compact Fluorescent Lamps, Tungsten-Halogen Lamps, Metal Halidemore » and HPS Lamps, Daylighting and Lumen Maintenance, Occupant Sensors, Time Scheduling Systems, and Retrofit Control Technologies -- each provide a product technology overview, discuss current products on the lighting equipment market, and provide application techniques. This document is intended for use by electric utility personnel involved in lighting programs, lighting designers, electrical engineers, architects, lighting manufacturers` representatives, and other lighting professionals.« less

Lithium-sulfur batteries: electrochemistry, materials, and prospects.

PubMed

Yin, Ya-Xia; Xin, Sen; Guo, Yu-Guo; Wan, Li-Jun

2013-12-09

With the increasing demand for efficient and economic energy storage, Li-S batteries have become attractive candidates for the next-generation high-energy rechargeable Li batteries because of their high theoretical energy density and cost effectiveness. Starting from a brief history of Li-S batteries, this Review introduces the electrochemistry of Li-S batteries, and discusses issues resulting from the electrochemistry, such as the electroactivity and the polysulfide dissolution. To address these critical issues, recent advances in Li-S batteries are summarized, including the S cathode, Li anode, electrolyte, and new designs of Li-S batteries with a metallic Li-free anode. Constructing S molecules confined in the conductive microporous carbon materials to improve the cyclability of Li-S batteries serves as a prospective strategy for the industry in the future. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Light-Duty Diesel Vehicles: Efficiency and Emissions Attributes and Market Issues

EIA Publications

2009-01-01

This report responds to a request from Senator Jeff Sessions for an analysis of the environmental and energy efficiency attributes of light-duty diesel vehicles. Specifically, the inquiry asked for a comparison of the characteristics of diesel-fueled vehicles with those of similar gasoline-fueled, E85-fueled, and hybrid vehicles, as well as a discussion of any technical, economic, regulatory, or other obstacles to increasing the use of diesel-fueled vehicles in the United States

New Hampshire Better Buildings - Final Report

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

Cramton, Karen; Peters, Katherine

2014-11-01

With $10 million in funding from the U.S. Department of Energy's (DOE) Better Buildings Neighborhood Program, the NH Better Buildings program was established as an initiative that initially empowered the three “Beacon Communities” of Berlin, Nashua and Plymouth to achieve transformative energy savings and reductions in fossil fuel use and greenhouse gases through deep energy retrofits and complementary sustainable energy solutions. The program also enabled those Communities to provide leadership to other communities around the state as “beacons” of energy efficiency. The goal of the program was to reduce energy use by a minimum of 15% through energy efficiency upgradesmore » in residential and commercial buildings in the communities. The program expanded statewide in April 2012 by issuing a competitive solicitation for additional commercial projects non-profit, and municipal energy efficiency projects from any community in the state, and a partnership with the state’s utility-run, ratepayer-funded residential Home Performance with ENERGY STAR® (HPwES) program. The NH Better Buildings program was administered by the New Hampshire Office of Energy and Planning (OEP) and managed by the NH Community Development Finance Authority (CDFA). The program started in July 2010 and the last projects funded with American Reinvestment and Recovery Act (ARRA) funds were completed in August 2013. The program will continue after the American Recovery and Reinvestment Act program period as a Revolving Loan Fund, enabling low-interest financing for deep energy retrofits into the future.« less

Multijunction cells for concentrators: Technology prospects

NASA Technical Reports Server (NTRS)

Ferber, R. R. (Compiler); Costogue, E. N. (Compiler); Shimada, K. (Compiler)

1984-01-01

Development of high-efficiency multijunction solar cells for concentrator applications is a key step in achieving the goals of the U.S. Department of Energy National Photovoltaics Program. This report summarizes findings of an issue study conducted by the Jet Propulsion Laboratory Photovoltaic Analysis and Integration Center, with the assistance of the Solar Energy Research Institute and Sandia National laboratoies, which surveyed multijunction cell research for concentrators undertaken by federal agencies and by private industry. The team evaluated the potentials of research activities sponsored by DOE and by corporate funding to achieve projected high-efficiency goals and developed summary statements regarding industry expectations. Recommendations are made for the direction of future work to address specific unresolved aspects of multijunction cell technology.

Not Too Hot, Not Too Cold - Continuum Magazine | NREL

Science.gov Websites

management technologies increase vehicle energy efficiency and performance while reducing costs. Mythological automobiles. Issues with thermal management cause some of these limitations. A photo of a white disk submerged sector petroleum consumption. Manufacturers and operators alike are looking to new thermal management

Waste Not

ERIC Educational Resources Information Center

Kennedy, Mike

2010-01-01

When schools and universities look at saving energy in their facilities, they are likely to review the efficiency of their heating and cooling systems, or the quality of their building envelopes. When facility managers focus attention on school bathrooms, they are more likely to consider issues such as cleanliness and safety as more critical than…

Searching for Hidden Costs: A Technology-Based Approach to the Energy Efficiency Gap in Light-Duty Vehicles, Presentation made at the Association of Environmental and Resource Economists Annual Conference

EPA Pesticide Factsheets

This presentation contains research on consumer issues, including an assessment of vehicle affordability, a study of willingness-to-pay for various vehicle attributes, and content analysis of auto reviews.

78 FR 50026 - Energy Efficiency and Conservation Loan Program Finding of No Significant Impact

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-16

... impact analysis documented in a programmatic environmental assessment of the new program that was issued... environment. Therefore, RUS will not prepare an environmental impact statement for its rulemaking adding... Finding of No Significant Impact AGENCY: Rural Utilities Service, USDA. ACTION: Notice of availability of...

Heating Efficiency of Beat Wave Excitation in a Density Gradient,

DTIC Science & Technology

1988-02-01

and Technology, January 1988. PPG-1124 񓟣 Research Highlights in The Pisces Program," R.V. Conn, et al, January 1988. PPG-1125 "Magnetic Fusion ... Energy , vol. 5. Technical Assessement of Critical Issues in the Steady State Operation of Fusion Confinement Devices," D. M. Goebel, Assessment Chairman

CHP -- A revolution in the making

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

Green, D.

1999-07-01

Liberalization, globalization, and particularly climate change are changing energy thinking. In the future, climate change will be tackled by improved energy efficiency and carbon neutral sources of energy, but much more could be done today by the more widespread use of CHP. CHP has made reasonably good progress in the UK and Europe, due to energy industry liberalization and the widespread availability of gas. But the pursuit of sustainability objectives requires government intervention into liberalized markets. While the current UK Government is a strong supporter of CHP, major opportunities to develop CHP were missed in favor of less efficient CCGTmore » power stations over the last decade. The two critical policy issues in the UK now are the proposed tax on the business use of energy and the current reform of electricity trading arrangements. Both could impact favorably on the development of CHP. The UK CHP Association, COGEN Europe and the International Cogeneration Alliance continue to press the case for CHP.« less

Feasibility study of tuned liquid column damper for ocean wave energy extraction

NASA Astrophysics Data System (ADS)

Wong, Yihong; King, Yeong-Jin; Lai, An-Chow; Chong, Kok-Keong; Lim, Boon-Han

2017-04-01

Intermittent nature and low efficiency are the major issues in renewable energy supply. To overcome these issues, one of the possible methods is through a hybrid system where multiple sources of renewable energy are combined to compensate each other's weaknesses. The hybrid of solar energy and wave energy becomes possible through the introduction of a stable floating platform which enables solar energy generation above it and wave energy harvesting underneath it. This paper is intended to study the feasibility of harnessing ocean wave energy using a tuned liquid column damper (TLCD), a type of passive damping device that is designed to suppress externally induced vibration force at a specific frequency range. The proposed TLCD is to be implemented within a floating offshore structure to serve as a vibration mitigating mechanism by reducing the dynamic response of the structure and simultaneously utilize the flowing motion of liquid within the TLCD for generating electricity. The constructed TLCD prototype is tuned according to theoretical study and tested using a shaking table with a predetermined frequency range. The oscillating motion of water within the TLCD and the potential of installation of hydro turbine generator in term of recoverable amount of energy are studied.

Multilayer Lead-Free Ceramic Capacitors with Ultrahigh Energy Density and Efficiency.

PubMed

Li, Jinglei; Li, Fei; Xu, Zhuo; Zhang, Shujun

2018-06-26

The utilization of antiferroelectric (AFE) materials is thought to be an effective approach to enhance the energy density of dielectric capacitors. However, the high energy dissipation and inferior reliability that are associated with the antiferroelectric-ferroelectric phase transition are the main issues that restrict the applications of antiferroelectric ceramics. Here, simultaneously achieving high energy density and efficiency in a dielectric ceramic is proposed by combining antiferroelectric and relaxor features. Based on this concept, a lead-free dielectric (Na 0.5 Bi 0.5 )TiO 3 -x(Sr 0.7 Bi 0.2 )TiO 3 (NBT-xSBT) system is investigated and the corresponding multilayer ceramic capacitors (MLCCs) are fabricated. A record-high energy density of 9.5 J cm -3 , together with a high energy efficiency of 92%, is achieved in NBT-0.45SBT multilayer ceramic capacitors, which consist of ten dielectric layers with the single-layer thickness of 20 µm and the internal electrode area of 6.25 mm 2 . Furthermore, the newly developed capacitor exhibits a wide temperature usage range of -60 to 120 °C, with an energy-density variation of less than 10%, and satisfactory cycling reliability, with degradation of less than 8% over 10 6 cycles. These characteristics demonstrate that the NBT-0.45SBT multilayer ceramic is a promising candidate for high-power energy storage applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Smart Grid Development Issues for Terrestrial and Space Applications

NASA Technical Reports Server (NTRS)

Soeder, James F.

2011-01-01

The development of the so called Smart Grid has as many definitions as individuals working in the area. Based on the technology or technologies that are of interest, be it high speed communication, renewable generation, smart meters, energy storage, advanced sensors, etc. they can become the individual defining characteristic of the Smart Grid. In reality the smart grid encompasses all of these items and quite at bit more. This discussion attempts to look at what the needs are for the grid of the future, such as the issues of increased power flow capability, use of renewable energy, increased security and efficiency and common power and data standards. It also shows how many of these issues are common with the needs of NASA for future exploration programs. A common theme to address both terrestrial and space exploration issues is to develop micro-grids that advertise the ability to enable the load leveling of large power generation facilities. However, for microgrids to realize their promise there needs to a holistic systems approach to their development and integration. The overall system integration issues are presented along with potential solution methodologies.

Smart Grid Development Issues for Terrestrial and Space Applications

NASA Technical Reports Server (NTRS)

Soeder, James F.

2014-01-01

The development of the so called Smart Grid has as many definitions as individuals working in the area. Based on the technology or technologies that are of interest, be it high speed communication, renewable generation, smart meters, energy storage, advanced sensors, etc. they can become the individual defining characteristic of the Smart Grid. In reality the smart grid encompasses all of these items and quite at bit more. This discussion attempts to look at what the needs are for the grid of the future, such as the issues of increased power flow capability, use of renewable energy, increased security and efficiency and common power and data standards. It also shows how many of these issues are common with the needs of NASA for future exploration programs. A common theme to address both terrestrial and space exploration issues is to develop micro-grids that advertise the ability to enable the load leveling of large power generation facilities. However, for microgrids to realize their promise there needs to a holistic systems approach to their development and integration. The overall system integration issues are presented along with potential solution methodologies.

3D-Printed, All-in-One Evaporator for High-Efficiency Solar Steam Generation under 1 Sun Illumination.

PubMed

Li, Yiju; Gao, Tingting; Yang, Zhi; Chen, Chaoji; Luo, Wei; Song, Jianwei; Hitz, Emily; Jia, Chao; Zhou, Yubing; Liu, Boyang; Yang, Bao; Hu, Liangbing

2017-07-01

Using solar energy to generate steam is a clean and sustainable approach to addressing the issue of water shortage. The current challenge for solar steam generation is to develop easy-to-manufacture and scalable methods which can convert solar irradiation into exploitable thermal energy with high efficiency. Although various material and structure designs have been reported, high efficiency in solar steam generation usually can be achieved only at concentrated solar illumination. For the first time, 3D printing to construct an all-in-one evaporator with a concave structure for high-efficiency solar steam generation under 1 sun illumination is used. The solar-steam-generation device has a high porosity (97.3%) and efficient broadband solar absorption (>97%). The 3D-printed porous evaporator with intrinsic low thermal conductivity enables heat localization and effectively alleviates thermal dissipation to the bulk water. As a result, the 3D-printed evaporator has a high solar steam efficiency of 85.6% under 1 sun illumination (1 kW m -2 ), which is among the best compared with other reported evaporators. The all-in-one structure design using the advanced 3D printing fabrication technique offers a new approach to solar energy harvesting for high-efficiency steam generation. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High performance Li-ion sulfur batteries enabled by intercalation chemistry.

PubMed

Lv, Dongping; Yan, Pengfei; Shao, Yuyan; Li, Qiuyan; Ferrara, Seth; Pan, Huilin; Graff, Gordon L; Polzin, Bryant; Wang, Chongmin; Zhang, Ji-Guang; Liu, Jun; Xiao, Jie

2015-09-11

The unstable interface of lithium metal in high energy density Li sulfur (Li-S) batteries raises concerns of poor cycling, low efficiency and safety issues, which may be addressed by using intercalation types of anode. Herein, a new prototype of Li-ion sulfur battery with high performance has been demonstrated by coupling a graphite anode with a sulfur cathode (2 mA h cm(-2)) after successfully addressing the interface issue of graphite in an ether based electrolyte.

Multistage Stochastic Programming and its Applications in Energy Systems Modeling and Optimization

NASA Astrophysics Data System (ADS)

Golari, Mehdi

Electric energy constitutes one of the most crucial elements to almost every aspect of life of people. The modern electric power systems face several challenges such as efficiency, economics, sustainability, and reliability. Increase in electrical energy demand, distributed generations, integration of uncertain renewable energy resources, and demand side management are among the main underlying reasons of such growing complexity. Additionally, the elements of power systems are often vulnerable to failures because of many reasons, such as system limits, weak conditions, unexpected events, hidden failures, human errors, terrorist attacks, and natural disasters. One common factor complicating the operation of electrical power systems is the underlying uncertainties from the demands, supplies and failures of system components. Stochastic programming provides a mathematical framework for decision making under uncertainty. It enables a decision maker to incorporate some knowledge of the intrinsic uncertainty into the decision making process. In this dissertation, we focus on application of two-stage and multistage stochastic programming approaches to electric energy systems modeling and optimization. Particularly, we develop models and algorithms addressing the sustainability and reliability issues in power systems. First, we consider how to improve the reliability of power systems under severe failures or contingencies prone to cascading blackouts by so called islanding operations. We present a two-stage stochastic mixed-integer model to find optimal islanding operations as a powerful preventive action against cascading failures in case of extreme contingencies. Further, we study the properties of this problem and propose efficient solution methods to solve this problem for large-scale power systems. We present the numerical results showing the effectiveness of the model and investigate the performance of the solution methods. Next, we address the sustainability issue considering the integration of renewable energy resources into production planning of energy-intensive manufacturing industries. Recently, a growing number of manufacturing companies are considering renewable energies to meet their energy requirements to move towards green manufacturing as well as decreasing their energy costs. However, the intermittent nature of renewable energies imposes several difficulties in long term planning of how to efficiently exploit renewables. In this study, we propose a scheme for manufacturing companies to use onsite and grid renewable energies provided by their own investments and energy utilities as well as conventional grid energy to satisfy their energy requirements. We propose a multistage stochastic programming model and study an efficient solution method to solve this problem. We examine the proposed framework on a test case simulated based on a real-world semiconductor company. Moreover, we evaluate long-term profitability of such scheme via so called value of multistage stochastic programming.

Bio-mimic optimization strategies in wireless sensor networks: a survey.

PubMed

Adnan, Md Akhtaruzzaman; Abdur Razzaque, Mohammd; Ahmed, Ishtiaque; Isnin, Ismail Fauzi

2013-12-24

For the past 20 years, many authors have focused their investigations on wireless sensor networks. Various issues related to wireless sensor networks such as energy minimization (optimization), compression schemes, self-organizing network algorithms, routing protocols, quality of service management, security, energy harvesting, etc., have been extensively explored. The three most important issues among these are energy efficiency, quality of service and security management. To get the best possible results in one or more of these issues in wireless sensor networks optimization is necessary. Furthermore, in number of applications (e.g., body area sensor networks, vehicular ad hoc networks) these issues might conflict and require a trade-off amongst them. Due to the high energy consumption and data processing requirements, the use of classical algorithms has historically been disregarded. In this context contemporary researchers started using bio-mimetic strategy-based optimization techniques in the field of wireless sensor networks. These techniques are diverse and involve many different optimization algorithms. As far as we know, most existing works tend to focus only on optimization of one specific issue of the three mentioned above. It is high time that these individual efforts are put into perspective and a more holistic view is taken. In this paper we take a step in that direction by presenting a survey of the literature in the area of wireless sensor network optimization concentrating especially on the three most widely used bio-mimetic algorithms, namely, particle swarm optimization, ant colony optimization and genetic algorithm. In addition, to stimulate new research and development interests in this field, open research issues, challenges and future research directions are highlighted.

Synergies and trade-offs between energy-efficient urbanization and health

NASA Astrophysics Data System (ADS)

Ahmad, Sohail; Pachauri, Shonali; Creutzig, Felix

2017-11-01

Energy-efficient urbanization and public health pose major development challenges for India. While both issues are intensively studied, their interaction is not well understood. Here we explore the relationship between urban infrastructures, public health, and household-related emissions, identifying potential synergies and trade-offs of specific interventions by analyzing nationally representative household surveys from 2005 and 2012. Our analysis confirms previous characterizations of the environmental-health transition, but also points to an important role of energy use and urbanization as modifiers of this transition. We find that non-motorized transport may prove a sweet spot for development, as its use is associated with lower emissions and better public health in cities. Urbanization and improved access to basic services correlate with lower short-term morbidity (STM), such as fever, cough and diarrhea. Our analysis suggests that a 10% increase in urbanization from current levels and concurrent improvement in access to modern cooking and clean water could lower STM for 2.4 million people. This would be associated with a modest increase in electricity related emissions of 84 ktCO2e annually. Promoting energy-efficient mobility systems, for instance by a 10% increase in bicycling, could lower chronic conditions like diabetes and cardio-vascular diseases for 0.3 million people while also abating emissions. These findings provide empirical evidence to validate that energy-efficient and sustainable urbanization can address both public health and climate change challenges simultaneously.

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.

Energy Performance Assessment of Virtualization Technologies Using Small Environmental Monitoring Sensors

PubMed Central

Liu, Lu; Masfary, Osama; Antonopoulos, Nick

2012-01-01

The increasing trends of electrical consumption within data centres are a growing concern for business owners as they are quickly becoming a large fraction of the total cost of ownership. Ultra small sensors could be deployed within a data centre to monitor environmental factors to lower the electrical costs and improve the energy efficiency. Since servers and air conditioners represent the top users of electrical power in the data centre, this research sets out to explore methods from each subsystem of the data centre as part of an overall energy efficient solution. In this paper, we investigate the current trends of Green IT awareness and how the deployment of small environmental sensors and Site Infrastructure equipment optimization techniques which can offer a solution to a global issue by reducing carbon emissions. PMID:22778660

Towards efficient solar hydrogen production by intercalated carbon nitride photocatalyst.

PubMed

Gao, Honglin; Yan, Shicheng; Wang, Jiajia; Huang, Yu An; Wang, Peng; Li, Zhaosheng; Zou, Zhigang

2013-11-07

The development of efficient photocatalytic material for converting solar energy to hydrogen energy as viable alternatives to fossil-fuel technologies is expected to revolutionize energy shortage and environment issues. However, to date, the low quantum yield for solar hydrogen production over photocatalysts has hindered advances in the practical applications of photocatalysis. Here, we show that a carbon nitride intercalation compound (CNIC) synthesized by a simple molten salt route is an efficient polymer photocatalyst with a high quantum yield. We found that coordinating the alkali metals into the C-N plane of carbon nitride will induce the un-uniform spatial charge distribution. The electrons are confined in the intercalated region while the holes are in the far intercalated region, which promoted efficient separation of photogenerated carriers. The donor-type alkali metal ions coordinating into the nitrogen pots of carbon nitrides increase the free carrier concentration and lead to the formation of novel nonradiative paths. This should favor improved transport of the photogenerated electron and hole and decrease the electron-hole recombination rate. As a result, the CNIC exhibits a quantum yield as high as 21.2% under 420 nm light irradiation for solar hydrogen production. Such high quantum yield opens up new opportunities for using cheap semiconducting polymers as energy transducers.

Review of Evaluation, Measurement and Verification Approaches Used to Estimate the Load Impacts and Effectiveness of Energy Efficiency Programs

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

Messenger, Mike; Bharvirkar, Ranjit; Golemboski, Bill

Public and private funding for end-use energy efficiency actions is expected to increase significantly in the United States over the next decade. For example, Barbose et al (2009) estimate that spending on ratepayer-funded energy efficiency programs in the U.S. could increase frommore » $3.1 billion in 2008 to $$7.5 and 12.4 billion by 2020 under their medium and high scenarios. This increase in spending could yield annual electric energy savings ranging from 0.58% - 0.93% of total U.S. retail sales in 2020, up from 0.34% of retail sales in 2008. Interest in and support for energy efficiency has broadened among national and state policymakers. Prominent examples include {approx}$$18 billion in new funding for energy efficiency programs (e.g., State Energy Program, Weatherization, and Energy Efficiency and Conservation Block Grants) in the 2009 American Recovery and Reinvestment Act (ARRA). Increased funding for energy efficiency should result in more benefits as well as more scrutiny of these results. As energy efficiency becomes a more prominent component of the U.S. national energy strategy and policies, assessing the effectiveness and energy saving impacts of energy efficiency programs is likely to become increasingly important for policymakers and private and public funders of efficiency actions. Thus, it is critical that evaluation, measurement, and verification (EM&V) is carried out effectively and efficiently, which implies that: (1) Effective program evaluation, measurement, and verification (EM&V) methodologies and tools are available to key stakeholders (e.g., regulatory agencies, program administrators, consumers, and evaluation consultants); and (2) Capacity (people and infrastructure resources) is available to conduct EM&V activities and report results in ways that support program improvement and provide data that reliably compares achieved results against goals and similar programs in other jurisdictions (benchmarking). The National Action Plan for Energy Efficiency (2007) presented commonly used definitions for EM&V in the context of energy efficiency programs: (1) Evaluation (E) - The performance of studies and activities aimed at determining the effects and effectiveness of EE programs; (2) Measurement and Verification (M&V) - Data collection, monitoring, and analysis associated with the calculation of gross energy and demand savings from individual measures, sites or projects. M&V can be a subset of program evaluation; and (3) Evaluation, Measurement, and Verification (EM&V) - This term is frequently seen in evaluation literature. EM&V is a catchall acronym for determining both the effectiveness of program designs and estimates of load impacts at the portfolio, program and project level. This report is a scoping study that assesses current practices and methods in the evaluation, measurement and verification (EM&V) of ratepayer-funded energy efficiency programs, with a focus on methods and practices currently used for determining whether projected (ex-ante) energy and demand savings have been achieved (ex-post). M&V practices for privately-funded energy efficiency projects (e.g., ESCO projects) or programs where the primary focus is greenhouse gas reductions were not part of the scope of this study. We identify and discuss key purposes and uses of current evaluations of end-use energy efficiency programs, methods used to evaluate these programs, processes used to determine those methods; and key issues that need to be addressed now and in the future, based on discussions with regulatory agencies, policymakers, program administrators, and evaluation practitioners in 14 states and national experts in the evaluation field. We also explore how EM&V may evolve in a future in which efficiency funding increases significantly, innovative mechanisms for rewarding program performance are adopted, the role of efficiency in greenhouse gas mitigation is more closely linked, and programs are increasingly funded from multiple sources often with multiple program administrators and intended to meet multiple purposes.« less

Using system-of-systems simulation modeling and analysis to measure energy KPP impacts for brigade combat team missions.

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

Lawton, Craig R.; Welch, Kimberly M.; Kerper, Jessica

2010-06-01

The Department of Defense's (DoD) Energy Posture identified dependence of the US Military on fossil fuel energy as a key issue facing the military. Inefficient energy consumption leads to increased costs, effects operational performance and warfighter protection through large and vulnerable logistics support infrastructures. Military's use of energy is a critical national security problem. DoD's proposed metrics Fully Burdened Cost of Fuel and Energy Efficiency Key Performance Parameter (FBCF and Energy KPP) are a positive step to force energy use accountability onto Military programs. The ability to measure impacts of sustainment are required to fully measure Energy KPP. Sandia's workmore » with Army demonstrates the capability to measure performance which includes energy constraint.« less

Feasibility Study to Identify Potential Reductions in Energy Use in Tribal Buildings

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

Stevens, Willie

Under this project, the Confederated Salish and Kootenai Tribes (CSKT) assessed the technical and economic feasibility of energy efficiency improvements to existing Tribally-owned buildings. The feasibility study followed a systematic approach in identifying, selecting, and ranking recommended measures, recognizing that the appropriateness of a measure would depend not only on technical issues but also on institutional and organizational issues, such as financing options and occupant requirements. The completed study provided the Tribes with the information needed to commit necessary resources to reduce the energy use and cost in approximately 40 Tribal buildings, including the changes that may be needed inmore » each facility’s operation and maintenance and personnel requirements. It also presented an economic analysis of energy-efficiency capital improvements and an annotated list of financing options and possible funding sources for implementation and an overall strategy for implementation. This project was located in various Tribal communities located throughout the Flathead Indian Reservation in Western Montana. Notice: The following is a compilation of Annual Program Review Presentations, Award Modifications, and Quarterly Progress Reports submitted to the Department of Energy’s (DOE) Office of Indian Energy Policy and Programs by the Confederated Salish and Kootenai Tribes under agreement DE-EE0005171. This report covers project activities from September 30, 2011 through December 31, 2014 and has been uploaded to OSTI by DOE as a substitute for the required Final Technical Report which was not received by DOE from the project recipient.« less

Green survivability in Fiber-Wireless (FiWi) broadband access network

NASA Astrophysics Data System (ADS)

Liu, Yejun; Guo, Lei; Gong, Bo; Ma, Rui; Gong, Xiaoxue; Zhang, Lincong; Yang, Jiangzi

2012-03-01

Fiber-Wireless (FiWi) broadband access network is a promising "last mile" access technology, because it integrates wireless and optical access technologies in terms of their respective merits, such as high capacity and stable transmission from optical access technology, and easy deployment and flexibility from wireless access technology. Since FiWi is expected to carry a large amount of traffic, numerous traffic flows may be interrupted by the failure of network components. Thus, survivability in FiWi is a key issue aiming at reliable and robust service. However, the redundant deployment of backup resource required for survivability usually causes huge energy consumption, which aggravates the global warming and accelerates the incoming of energy crisis. Thus, the energy-saving issue should be considered when it comes to survivability design. In this paper, we focus on the green survivability in FiWi, which is an innovative concept and remains untouched in the previous works to our best knowledge. We first review and discuss some challenging issues about survivability and energy-saving in FiWi, and then we propose some instructive solutions for its green survivability design. Therefore, our work in this paper will provide the technical references and research motivations for the energy-efficient and survivable FiWi development in the future.

Issues in the deregulation of the electric industry

NASA Astrophysics Data System (ADS)

Tyler, Cleve Brent

The electric industry is undergoing a major restructuring which allows competition in the generation portion of the industry. This dissertation explores several pricing issues relevant to this restructuring. First, an extensive overview examines the industry's history, discusses major regulation theories, and relays the major issues of deregulation. Second, a literature review recounts major works in the economics literature on price discrimination, pricing efficiency, and cost estimation. Then, customer specific generation, transmission, distribution, and general and administration costs are estimated for each company. The customer classes are residential, general service, large general service, and large industrial, representing a finer division of customer classes than found in previous studies. Average prices are compiled and marginal prices are determined from a set of utility schedules. Average and marginal price/cost ratios are computed for each customer class. These ratios show that larger use customers face relative price discrimination but operate under more efficient price structures than small use consumers. Finally, issues in peak load pricing are discussed using a model which predicts inefficient capital choice by regulated utilities. Efficiency losses are estimated to be $620 million dollars a year from the lack of peak load prices under regulation. This result is based on the time-of-use pricing predictions from the Department of Energy.

Reducing Our Carbon Footprint: A Low-Energy House in Berkeley, Kabul, and Washington DC (LBNL Science at the Theater)

ScienceCinema

Diamond, Rick [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2018-05-14

How well can we assess and improve building energy performance in California homes? How much energy-and carbon-do homes use in other parts of the world? Rick Diamond, deputy group leader of the Berkeley Lab Energy Performance of Buildings Group, discusses change, global solutions, and the stories of three houses in Berkeley, Kabul (Afghanistan), and Washington, D.C. Diamond, who is also a senior advisor at the California Institute for Energy and Environment, investigates user interactions with the built environment for improved building energy performance. The group has studied a wide range of issues related to energy use in housing, including duct system efficiency, user behavior, and infiltration and ventilation measurements.

Offshore Energy Mapping for Northeast Atlantic and Mediterranean: MARINA PLATFORM project

NASA Astrophysics Data System (ADS)

Kallos, G.; Galanis, G.; Spyrou, C.; Kalogeri, C.; Adam, A.; Athanasiadis, P.

2012-04-01

Deep offshore ocean energy mapping requires detailed modeling of the wind, wave, tidal and ocean circulation estimations. It requires also detailed mapping of the associated extremes. An important issue in such work is the co-generation of energy (generation of wind, wave, tides, currents) in order to design platforms on an efficient way. For example wind and wave fields exhibit significant phase differences and therefore the produced energy from both sources together requires special analysis. The other two sources namely tides and currents have different temporal scales from the previous two. Another important issue is related to the estimation of the environmental frequencies in order to avoid structural problems. These are issues studied at the framework of the FP7 project MARINA PLATFORM. The main objective of the project is to develop deep water structures that can exploit the energy from wind, wave, tidal and ocean current energy sources. In particular, a primary goal will be the establishment of a set of equitable and transparent criteria for the evaluation of multi-purpose platforms for marine renewable energy. Using these criteria, a novel system set of design and optimisation tools will be produced addressing new platform design, component engineering, risk assessment, spatial planning, platform-related grid connection concepts, all focussed on system integration and reducing costs. The University of Athens group is in charge for estimation and mapping of wind, wave, tidal and ocean current resources, estimate available energy potential, map extreme event characteristics and provide any additional environmental parameter required.

Reflections on fifteen years of energy policy

NASA Astrophysics Data System (ADS)

Gibbons, John H.

1985-11-01

The events of the 1970's—both the ``energy crises'' and the measures taken to alleviate them—changed our ways of thinking about energy. We now look at energy consumption as a largely substitutable means to various ends, not a goal or a measure of progress in and of itself. Energy demand growth has dropped markedly, even as the economy has grown. But there are many issues yet to be resolved if the United States is to have a comprehensive, rotational energy strategy. This paper tackles four of them: Is there a place for continued government economic and regulatory intervention in the energy marketplace? What should be the federal role in energy research and development? What are our prospects for new discoveries in domestic oil and gas? What is the future of nuclear power in the United States? The author believes that the best way to solve our energy problems is to gauge, and then reflect in our energy policy, the true costs and benefits of energy production and consumption. He concludes that conservation investments have proven to be so rewarding that energy efficiency should be receiving a major amount of attention from energy policy makers for reasons of economic efficiency and in order to minimize the impact of future crises.

Realizing Efficient Energy Harvesting from Organic Photovoltaic Cells

NASA Astrophysics Data System (ADS)

Zou, Yunlong

Organic photovoltaic cells (OPVs) are emerging field of research in renewable energy. The development of OPVs in recent years has made this technology viable for many niche applications. In order to realize widespread application however, the power conversion efficiency requires further improvement. The efficiency of an OPV depends on the short-circuit current density (JSC), open-circuit voltage (VOC) and fill factor (FF). For state-of-the-art devices, JSC is mostly optimized with the application of novel low-bandgap materials and a bulk heterojunction device architecture (internal quantum efficiency approaching 100%). The remaining limiting factors are the low VOC and FF. This work focuses on overcoming these bottlenecks for improved efficiency. Temperature dependent measurements of device performance are used to examine both charge transfer and exciton ionization process in OPVs. The results permit an improved understanding of the intrinsic limit for VOC in various device architectures and provide insight on device operation. Efforts have also been directed at engineering device architecture for optimized FF, realizing a very high efficiency of 8% for vapor deposited small molecule OPVs. With collaborators, new molecules with tailored desired energy levels are being designed for further improvements in efficiency. A new type of hybrid organic-inorganic perovskite material is also included in this study. By addressing processing issues and anomalous hysteresis effects, a very high efficiency of 19.1% is achieved. Moving forward, topics including engineering film crystallinity, exploring tandem architectures and understanding degradation mechanisms will further push OPVs toward broad commercialization.

Solar thermal electric hybridization issues

NASA Astrophysics Data System (ADS)

Williams, Tom A.; Bohn, Mark S.; Price, Henry W.

1994-10-01

Solar thermal electric systems have an advantage over many other renewable energy technologies because the former use heat as an intermediate energy carrier. This is an advantage, as it allows for a relatively simple method of hybridization by using heat from fossil-fuel. Hybridization of solar thermal electric systems is a topic that has recently generated significant interest and controversy and has led to many diverse opinions. This paper discusses many of the issues associated with hybridization of solar thermal electric systems such as what role hybridization should play; how it should be implemented; what are the efficiency, environmental, and cost implications; what solar fraction is appropriate; how hybrid systems compete with solar-only systems; and how hybridization can impact commercialization efforts for solar thermal electric systems.

From Heavy-Ion Collisions to Quark Matter (2/3)

ScienceCinema

Lourenco, C.

2018-05-23

The art of experimental (high-energy heavy-ion) physics 1) many experimental issues are crucial to properly understand the measurements and derive a correct physics interpretation: Acceptance and phase space windows; Efficiencies (of track reconstruction, vertexing, track matching, trigger, etc); Resolutions (of mass, momenta, energies, etc); Backgrounds, feed-downs and "expected sources"; Data selection; Monte Carlo adjustments, calibrations and smearing; luminosity and trigger conditions; Evaluation of systematic uncertainties, and several others. 2) "New Physics" often appears as excesses or suppressions with respect to "normal baselines", which must be very carefully established, on the basis of "reference" physics processes and collision systems. If we misunderstand these issues we can miss an important discovery...or we can "discover" non-existent "new physics."

Microfabrication and integration of a sol-gel PZT folded spring energy harvester.

PubMed

Lueke, Jonathan; Badr, Ahmed; Lou, Edmond; Moussa, Walied A

2015-05-26

This paper presents the methodology and challenges experienced in the microfabrication, packaging, and integration of a fixed-fixed folded spring piezoelectric energy harvester. A variety of challenges were overcome in the fabrication of the energy harvesters, such as the diagnosis and rectification of sol-gel PZT film quality and adhesion issues. A packaging and integration methodology was developed to allow for the characterizing the harvesters under a base vibration. The conditioning circuitry developed allowed for a complete energy harvesting system, consisting a harvester, a voltage doubler, a voltage regulator and a NiMH battery. A feasibility study was undertaken with the designed conditioning circuitry to determine the effect of the input parameters on the overall performance of the circuit. It was found that the maximum efficiency does not correlate to the maximum charging current supplied to the battery. The efficiency and charging current must be balanced to achieve a high output and a reasonable output current. The development of the complete energy harvesting system allows for the direct integration of the energy harvesting technology into existing power management schemes for wireless sensing.

Microfabrication and Integration of a Sol-Gel PZT Folded Spring Energy Harvester

PubMed Central

Lueke, Jonathan; Badr, Ahmed; Lou, Edmond; Moussa, Walied A.

2015-01-01

This paper presents the methodology and challenges experienced in the microfabrication, packaging, and integration of a fixed-fixed folded spring piezoelectric energy harvester. A variety of challenges were overcome in the fabrication of the energy harvesters, such as the diagnosis and rectification of sol-gel PZT film quality and adhesion issues. A packaging and integration methodology was developed to allow for the characterizing the harvesters under a base vibration. The conditioning circuitry developed allowed for a complete energy harvesting system, consisting a harvester, a voltage doubler, a voltage regulator and a NiMH battery. A feasibility study was undertaken with the designed conditioning circuitry to determine the effect of the input parameters on the overall performance of the circuit. It was found that the maximum efficiency does not correlate to the maximum charging current supplied to the battery. The efficiency and charging current must be balanced to achieve a high output and a reasonable output current. The development of the complete energy harvesting system allows for the direct integration of the energy harvesting technology into existing power management schemes for wireless sensing. PMID:26016911

Solar energy conversion with photon-enhanced thermionic emission

NASA Astrophysics Data System (ADS)

Kribus, Abraham; Segev, Gideon

2016-07-01

Photon-enhanced thermionic emission (PETE) converts sunlight to electricity with the combined photonic and thermal excitation of charge carriers in a semiconductor, leading to electron emission over a vacuum gap. Theoretical analyses predict conversion efficiency that can match, or even exceed, the efficiency of traditional solar thermal and photovoltaic converters. Several materials have been examined as candidates for radiation absorbers and electron emitters, with no conclusion yet on the best set of materials to achieve high efficiency. Analyses have shown the complexity of the energy conversion and transport processes, and the significance of several loss mechanisms, requiring careful control of material properties and optimization of the device structure. Here we survey current research on PETE modeling, materials, and device configurations, outline the advances made, and stress the open issues and future research needed. Based on the substantial progress already made in this young topic, and the potential of high conversion efficiency based on theoretical performance limits, continued research in this direction is very promising and may yield a competitive technology for solar electricity generation.

A practical review of energy saving technology for ageing populations.

PubMed

Walker, Guy; Taylor, Andrea; Whittet, Craig; Lynn, Craig; Docherty, Catherine; Stephen, Bruce; Owens, Edward; Galloway, Stuart

2017-07-01

Fuel poverty is a critical issue for a globally ageing population. Longer heating/cooling requirements combine with declining incomes to create a problem in need of urgent attention. One solution is to deploy technology to help elderly users feel informed about their energy use, and empowered to take steps to make it more cost effective and efficient. This study subjects a broad cross section of energy monitoring and home automation products to a formal ergonomic analysis. A high level task analysis was used to guide a product walk through, and a toolkit approach was used thereafter to drive out further insights. The findings reveal a number of serious usability issues which prevent these products from successfully accessing an important target demographic and associated energy saving and fuel poverty outcomes. Design principles and examples are distilled from the research to enable practitioners to translate the underlying research into high quality design-engineering solutions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Global Potential of Energy Efficiency Standards and Labeling Programs

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

McNeil, Michael A; McNeil, Michael A.; Letschert, Virginie

2008-06-15

This report estimates the global potential reductions in greenhouse gas emissions by 2030 for energy efficiency improvements associated with equipment (appliances, lighting, and HVAC) in buildings by means of energy efficiency standards and labels (EES&L). A consensus has emerged among the world's scientists and many corporate and political leaders regarding the need to address the threat of climate change through emissions mitigation and adaptation. A further consensus has emerged that a central component of these strategies must be focused around energy, which is the primary generator of greenhouse gas emissions. Two important questions result from this consensus: 'what kinds ofmore » policies encourage the appropriate transformation to energy efficiency' and 'how much impact can these policies have'? This report aims to contribute to the dialogue surrounding these issues by considering the potential impacts of a single policy type, applied on a global scale. The policy addressed in this report is Energy Efficient Standards and Labeling (EES&L) for energy-consuming equipment, which has now been implemented in over 60 countries. Mandatory energy performance standards are important because they contribute positively to a nation's economy and provide relative certainty about the outcome (both timing and magnitudes). Labels also contribute positively to a nation's economy and importantly increase the awareness of the energy-consuming public. Other policies not analyzed here (utility incentives, tax credits) are complimentary to standards and labels and also contribute in significant ways to reducing greenhouse gas emissions. We believe the analysis reported here to be the first systematic attempt to evaluate the potential of savings from EES&L for all countries and for such a large set of products. The goal of the analysis is to provide an assessment that is sufficiently well-quantified and accurate to allow comparison and integration with other strategies under consideration.« less

Dimethyl ether (DME) as an alternative fuel

NASA Astrophysics Data System (ADS)

Semelsberger, Troy A.; Borup, Rodney L.; Greene, Howard L.

With ever growing concerns on environmental pollution, energy security, and future oil supplies, the global community is seeking non-petroleum based alternative fuels, along with more advanced energy technologies (e.g., fuel cells) to increase the efficiency of energy use. The most promising alternative fuel will be the fuel that has the greatest impact on society. The major impact areas include well-to-wheel greenhouse gas emissions, non-petroleum feed stocks, well-to-wheel efficiencies, fuel versatility, infrastructure, availability, economics, and safety. Compared to some of the other leading alternative fuel candidates (i.e., methane, methanol, ethanol, and Fischer-Tropsch fuels), dimethyl ether appears to have the largest potential impact on society, and should be considered as the fuel of choice for eliminating the dependency on petroleum. DME can be used as a clean high-efficiency compression ignition fuel with reduced NO x, SO x, and particulate matter, it can be efficiently reformed to hydrogen at low temperatures, and does not have large issues with toxicity, production, infrastructure, and transportation as do various other fuels. The literature relevant to DME use is reviewed and summarized to demonstrate the viability of DME as an alternative fuel.

The Nature of Sustainability as Viewed by European Students

ERIC Educational Resources Information Center

Lockley, John; Jarrath, Martin

2013-01-01

Sustainability as a concept, though well understood in general terms, is often politically captured by interest groups and as such expressed through issues like concern for global climate change or the need to develop more efficient energy sources, to address regional, national or international priorities. Education for sustainability as a concept…

75 FR 70852 - Energy Efficiency Program for Consumer Products: Public Meeting and Availability of the Framework...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-19

... is planning to conduct in-depth technical analyses in the following areas: (1) Engineering; (2... this rulemaking process, DOE has prepared a framework document to explain the relevant issues, analyses... development of any amended standards. The focus of the public meeting will be to discuss the analyses...

Going "Green": Environmental Jobs for Scientists and Engineers

ERIC Educational Resources Information Center

Ramey, Alice

2009-01-01

Green is often used as a synonym for environmental or ecological, especially as it relates to products and activities aimed at minimizing damage to the planet. Scientists and engineers have long had important roles in the environmental movement. Their expertise is focused on a variety of issues, including increasing energy efficiency, improving…

Energy performance assessment with empirical methods: application of energy signature

NASA Astrophysics Data System (ADS)

Belussi, L.; Danza, L.; Meroni, I.; Salamone, F.

2015-03-01

Energy efficiency and reduction of building consumption are deeply felt issues both at Italian and international level. The recent regulatory framework sets stringent limits on energy performance of buildings. Awaiting the adoption of these principles, several methods have been developed to solve the problem of energy consumption of buildings, among which the simplified energy audit is intended to identify any anomalies in the building system, to provide helpful tips for energy refurbishments and to raise end users' awareness. The Energy Signature is an operational tool of these methodologies, an evaluation method in which energy consumption is correlated with climatic variables, representing the actual energy behaviour of the building. In addition to that purpose, the Energy Signature can be used as an empirical tool to determine the real performances of the technical elements. The latter aspect is illustrated in this article.

Emerging policy issues in PURPA implementation: an examination of policy issues related to federal and state efforts to encourage development of cogeneration and small power production under Title II of PURPA

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

Not Available

Purpose of this study is to examine the results of FERG and state efforts to encourage the development of cogeneration and small power production under Title II of the Public Utility Regualtory Policies Act of 1978 (PURPA) in the years since the statute was enacted. The frame of reference specified by DOE for use in this study includes both the original purposes of the legislation as set forth in PURPA and the current overall energy policy goal which is to ''foster an adequate supply of energy at reasonable costs.'' This review of PURPA implementation efforts is designed to assess themore » results to date in terms of achieving the stated goals of the statute (including ''to encourage cogeneration and small power production''), identify perceived areas of conflict between federal and state efforts to maximize development of qualifying facilities (QFs) and current Administration concerns for achieving greater levels of economic efficiency in electric power supply, briefly examine the nature of such conflicts, with reference to specific cases wherever possible, and suggest possible means of conforming government efforts to encourage QF development with the economic efficiency objectives underlying national energy policy.« less

ARPA-E: Accelerating U.S. Energy Innovation

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

Manser, Joseph S.; Rollin, Joseph A.; Brown, Kristen E.

ARPA-E is charged with addressing the most pressing issues facing the U.S. energy sector today, as well as those projected to impact national energy security in the future. The agency’s mission is clearly elucidated in its authorizing statute:2 “To overcome long-term and high-risk technological barriers in the development of energy technologies.” The three principal thrusts of the agency’s mission are (i) reducing energy imports, (ii) reducing energy-related emissions and greenhouse gases, and (iii) improving energy efficiency in all sectors of the U.S. economy. Meeting these ambitious challenges requires focused, interdisciplinary effort on a national scale that will help ensure themore » United States maintains a competitive lead in developing and deploying advanced energy technologies.« less

Lean NOx Trap Catalysis for Lean Natural Gas Engine Applications

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

Parks, II, James E; Storey, John Morse; Theiss, Timothy J

Distributed energy is an approach for meeting energy needs that has several advantages. Distributed energy improves energy security during natural disasters or terrorist actions, improves transmission grid reliability by reducing grid load, and enhances power quality through voltage support and reactive power. In addition, distributed energy can be efficient since transmission losses are minimized. One prime mover for distributed energy is the natural gas reciprocating engine generator set. Natural gas reciprocating engines are flexible and scalable solutions for many distributed energy needs. The engines can be run continuously or occasionally as peak demand requires, and their operation and maintenance ismore » straightforward. Furthermore, system efficiencies can be maximized when natural gas reciprocating engines are combined with thermal energy recovery for cooling, heating, and power applications. Expansion of natural gas reciprocating engines for distributed energy is dependent on several factors, but two prominent factors are efficiency and emissions. Efficiencies must be high enough to enable low operating costs, and emissions must be low enough to permit significant operation hours, especially in non-attainment areas where emissions are stringently regulated. To address these issues the U.S. Department of Energy and the California Energy Commission launched research and development programs called Advanced Reciprocating Engine Systems (ARES) and Advanced Reciprocating Internal Combustion Engines (ARICE), respectively. Fuel efficiency and low emissions are two primary goals of these programs. The work presented here was funded by the ARES program and, thus, addresses the ARES 2010 goals of 50% thermal efficiency (fuel efficiency) and <0.1 g/bhp-hr emissions of oxides of nitrogen (NOx). A summary of the goals for the ARES program is given in Table 1-1. ARICE 2007 goals are 45% thermal efficiency and <0.015 g/bhp-hr NOx. Several approaches for improving the efficiency and emissions of natural gas reciprocating engines are being pursued. Approaches include: stoichiometric engine operation with exhaust gas recirculation and three-way catalysis, advanced combustion modes such as homogeneous charge compression ignition, and extension of the lean combustion limit with advanced ignition concepts and/or hydrogen mixing. The research presented here addresses the technical approach of combining efficient lean spark-ignited natural gas combustion with low emissions obtained from a lean NOx trap catalyst aftertreatment system. This approach can be applied to current lean engine technology or advanced lean engines that may result from related efforts in lean limit extension. Furthermore, the lean NOx trap technology has synergy with hydrogen-assisted lean limit extension since hydrogen is produced from natural gas during the lean NOx trap catalyst system process. The approach is also applicable to other lean engines such as diesel engines, natural gas turbines, and lean gasoline engines; other research activities have focused on those applications. Some commercialization of the technology has occurred for automotive applications (both diesel and lean gasoline engine vehicles) and natural gas turbines for stationary power. The research here specifically addresses barriers to commercialization of the technology for large lean natural gas reciprocating engines for stationary power. The report presented here is a comprehensive collection of research conducted by Oak Ridge National Laboratory (ORNL) on lean NOx trap catalysis for lean natural gas reciprocating engines. The research was performed in the Department of Energy's ARES program from 2003 to 2007 and covers several aspects of the technology. All studies were conducted at ORNL on a Cummins C8.3G+ natural gas engine chosen based on industry input to simulate large lean natural gas engines. Specific technical areas addressed by the research include: NOx reduction efficiency, partial oxidation and reforming chemistry, and the effects of sulfur poisons on the partial oxidation, reformer, and lean NOx trap catalysts. The initial work on NOx reduction efficiency demonstrated that NOx emissions <0.1 g/bhp-hr (the ARES goal) can be achieved with the lean NOx trap catalyst technology. Subsequent work focused on cost and size optimization and durability issues which addressed two specific ARES areas of interest to industry ('Cost of Power' and 'Availability, Reliability, and Maintainability', respectively). Thus, the research addressed the approach of the lean NOx trap catalyst technology toward the ARES goals as shown in Table 1-1.« less

Materials for Better Li-based Storage Systems for a "Green Energy Society"

ScienceCinema

Jean-Marie Tarascon

2017-12-09

Li-ion batteries are strongly considered for powering the upcoming generations of HEVs and PHEVs, but there are still the issues of safety and costs in terms of materials resources and abundances, synthesis, and recycling processes. Notions of materials having minimum footprint in nature, made via eco-efficient processes, must be integrated in our new research towards the next generation of sustainable and "greener" Li-ion batteries. In this July 13, 2009 talk sponsored by Berkeley Lab's Environental Energy Technologies Division, Jean-Marie Tarascon, a professor at the University of Picardie (Amiens), discuss Eco-efficient synthesis via hydrothermal/solvothermal processes using latent bases as well as structure directing templates or other bio-related approaches of LiFePO4 nanopowders.

Green chemistry for nanoparticle synthesis.

PubMed

Duan, Haohong; Wang, Dingsheng; Li, Yadong

2015-08-21

The application of the twelve principles of green chemistry in nanoparticle synthesis is a relatively new emerging issue concerning the sustainability. This field has received great attention in recent years due to its capability to design alternative, safer, energy efficient, and less toxic routes towards synthesis. These routes have been associated with the rational utilization of various substances in the nanoparticle preparations and synthetic methods, which have been broadly discussed in this tutorial review. This article is not meant to provide an exhaustive overview of green synthesis of nanoparticles, but to present several pivotal aspects of synthesis with environmental concerns, involving the selection and evaluation of nontoxic capping and reducing agents, the choice of innocuous solvents and the development of energy-efficient synthetic methods.

Broad Overview of Energy Efficiency and Renewable Energy Opportunities for Department of Defense Installations

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

Anderson, E.; Antkowiak, M.; Butt, R.

The Strategic Environmental Research and Developmental Program (SERDP)/Environmental Security Technology Certification Program (ESTCP) is the Department of Defense?s (DOD) environmental science and technology program focusing on issues related to environment and energy for the military services. The SERDP/ESTCP Office requested that the National Renewable Energy Laboratory (NREL) provide technical assistance with strategic planning by evaluating the potential for several types of renewable energy technologies at DOD installations. NREL was tasked to provide technical expertise and strategic advice for the feasibility of geothermal resources, waste-to-energy technology, photovoltaics (PV), wind, microgrids, and building system technologies on military installations. This technical report ismore » the deliverable for these tasks.« less

Evolution of the Utah energy research triangle: A contemporary case study in the nexus of applied research and public policy

NASA Astrophysics Data System (ADS)

Walker, Alan John

The evolution of the Utah Energy Research Triangle began August 2009 with Governor Gary Herbert's inauguration. On January 26, 2010 Governor Herbert delivered his first State of the State Address and announced the "most impactful economic initiative ever taken in our state...the Utah Energy Initiative." Even before this speech, actions were underway as the Governor assembled 16 energy professionals who forged Utah's 10-Year Strategic Energy Plan (Plan) released March 2011. The priorities in the Plan included: (1) establishing the Office of Energy Development in 2011; (2) launching the annual Governor's Energy Development Summits beginning in 2012; and (3) executing the first cycle of the Utah Energy Research Triangle in 2013 through 2015. Other objectives would be achieved as the Plan unfolded but those lower priorities are beyond the scope of this case study. This study will review the three priorities noted and focus on the execution of the Energy Research Triangle as a nexus of applied research and public policy. The Plan's vision was to "align the State's main research universities...into a powerful energy research and development triangle...through increased collaboration." In March 2014, execution of the first cycle of the Energy Research Triangle resulted in seven new research efforts across three research university campuses in Utah - Brigham Young University (BYU), Utah State University (USU), and the University of Utah (UofU). These research programs included eighteen researchers tackling principle energy issues: air quality, hydrocarbon transportation, and safety. Seven other researchers were awarded Governor's Energy Leadership Scholarships with requirements to address topics including efficient solar power, cold-weather battery performance, and molten salt energy storage. Final results will be known in June 2015, but collaboration on energy issues is active and ongoing. Together the three research teams are successfully reaching out to industry and federal agencies to expand their capability to address Utah energy issues. This case study provides a road map and lessons learned for developing a meaningful grass roots research program with modest resources. Public policy is notorious for cycling through good ideas. This study provides guidance to solve local issues using the collaborative capabilities of our universities.

Advanced Micro Grid Energy Management Coupled with Integrated Volt/VAR Control for Improved Energy Efficiency, Energy Security, and Power Quality at DoD Installations

DTIC Science & Technology

2016-10-28

constraints and wire routing issues. • Outside sites have more space, but require outdoor rated equipment (NEMA outdoor rated.. ) and more maintenance...sustainable power, in many different types, sizes and capacities, as follows: • Cogen Plant #1 B1579: 7.2MW gas-fired turbine at Substation “AA...Cogen Plant #2 B1991: (2) 4.6MW gas-fired turbines at “Gillespie” Substation • 300kW fuel cell at Substation “AA” • PPA: 1.015MW solar photovoltaic

Global CLEWs model - A novel application of OSeMOSYS

NASA Astrophysics Data System (ADS)

Avgerinopoulos, Georgios; Pereira Ramos, Eunice; Howells, Mark

2017-04-01

Over the past years, studies that analyse Nexus issues from a holistic point of view and not energy, land or water separately have been gaining momentum. This project aims at giving insights into global issues through the application and the analysis of a global scale OSeMOSYS model. The latter -which is based on a fully open and amendable code- has been used successfully in the latest years as it has been the producing fully accessible energy models suitable for capacity building and policy making suggestions. This study develops a CLEWs (climate, land, energy and water) model with the objective of interrogating global challenges (e.g. increasing food demand) and international trade features, with policy priorities on food security, resource efficiency, low-carbon energy and climate change mitigation, water availability and vulnerability to water stress and floods, water quality, biodiversity and ecosystem services. It will for instance assess (i) the impact of water constraints on food security and human development (clean water for human use; industrial and energy water demands), as well as (ii) the impact of climate change on aggravating or relieving water problems.

EIA's Role in Energy Data Collection, With Some Notes on Water Data

NASA Astrophysics Data System (ADS)

Leckey, T. J.

2017-12-01

The U.S. Energy Information Administration (EIA) is the statistical and analytical agency within the U.S. Department of Energy. EIA collects, analyzes, and disseminates independent and impartial energy information to promote sound policymaking, efficient markets, and public understanding of energy and its interaction with the economy and the environment. EIA conducts a comprehensive data collection program that covers the full spectrum of energy sources, end uses, and energy flows. This presentation will describe EIA's authority to collect energy data, report on the range of energy areas currently collected by EIA, discuss some areas where energy information and water issues intersect, and describe the relatively few areas where EIA does collect a small amount of water data. The presentation will conclude with some thoughts about necessary components for effective collection of water data at the federal level.

Energy-loss return gate via liquid dielectric polarization.

PubMed

Kim, Taehun; Yong, Hyungseok; Kim, Banseok; Kim, Dongseob; Choi, Dukhyun; Park, Yong Tae; Lee, Sangmin

2018-04-12

There has been much research on renewable energy-harvesting techniques. However, owing to increasing energy demands, significant energy-related issues remain to be solved. Efforts aimed at reducing the amount of energy loss in electric/electronic systems are essential for reducing energy consumption and protecting the environment. Here, we design an energy-loss return gate system that reduces energy loss from electric/electronic systems by utilizing the polarization of liquid dielectrics. The use of a liquid dielectric material in the energy-loss return gate generates electrostatic potential energy while reducing the dielectric loss of the electric/electronic system. Hence, an energy-loss return gate can make breakthrough impacts possible by amplifying energy-harvesting efficiency, lowering the power consumption of electronics, and storing the returned energy. Our study indicates the potential for enhancing energy-harvesting technologies for electric/electronics systems, while increasing the widespread development of these systems.

Promoting climate literacy through social engagement: the Green Ninja Project

NASA Astrophysics Data System (ADS)

Cordero, E. C.; Todd, A.

2012-12-01

One of the challenges of communicating climate change to younger audiences is the disconnect between global issues and local impacts. The Green Ninja is a climate-action superhero that aims to energize young people about climate science through media and social engagement tools. In this presentation, we'll highlight two of the tools designed to help K-12 students implement appropriate local mitigation strategies. A mobile phone application builds and supports a social community around taking action at local businesses regarding themes such as food, packaging and energy efficiency. An energy efficiency contest in local schools utilizes smart meter technology to provide feedback on household energy use and conservation. These tools are supported by films and lesson plans that link formal and informal education channels. The effectiveness of these methodologies as tools to engage young people in climate science and action will be discussed.

An analytical study on the performance of the organic Rankine cycle for turbofan engine exhaust heat recovery

NASA Astrophysics Data System (ADS)

Saadon, S.; Abu Talib, A. R.

2016-10-01

Due to energy shortage and global warming, issues of energy saving have become more important. To increase the energy efficiency and reduce the fuel consumption, waste heat recovery is a significant method for energy saving. The organic Rankine cycle (ORC) has great potential to recover the waste heat from the core jet exhaust of a turbofan engine and use it to produce power. Preliminary study of the design concept and thermodynamic performance of this ORC system would assist researchers to predict the benefits of using the ORC system to extract the exhaust heat engine. In addition, a mathematical model of the heat transfer of this ORC system is studied and developed. The results show that with the increment of exhaust heat temperature, the mass flow rate of the working fluid, net power output and the system thermal efficiency will also increase. Consequently, total consumption of jet fuel could be significantly saved as well.

Energy and fuels from electrochemical interfaces

DOE PAGES

Stamenkovic, Vojislav R.; Strmcnik, Dusan; Lopes, Pietro P.; ...

2016-12-20

Advances in electrocatalysis at solid–liquid interfaces are vital for driving the technological innovations that are needed to deliver reliable, affordable and environmentally friendly energy. Here, in this paper, we highlight the key achievements in the development of new materials for efficient hydrogen and oxygen production in electrolysers and, in reverse, their use in fuel cells. A key issue addressed here is the degree to which the fundamental understanding of the synergy between covalent and non-covalent interactions can form the basis for any predictive ability in tailor-making real-world catalysts. Common descriptors such as the substrate–hydroxide binding energy and the interactions inmore » the double layer between hydroxide-oxides and H---OH are found to control individual parts of the hydrogen and oxygen electrochemistry that govern the efficiency of water-based energy conversion and storage systems. Lastly, links between aqueous- and organic-based environments are also established, encouraging the 'fuel cell' and 'battery' communities to move forward together.« less

Bio-Mimic Optimization Strategies in Wireless Sensor Networks: A Survey

PubMed Central

Adnan, Md. Akhtaruzzaman; Razzaque, Mohammd Abdur; Ahmed, Ishtiaque; Isnin, Ismail Fauzi

2014-01-01

For the past 20 years, many authors have focused their investigations on wireless sensor networks. Various issues related to wireless sensor networks such as energy minimization (optimization), compression schemes, self-organizing network algorithms, routing protocols, quality of service management, security, energy harvesting, etc., have been extensively explored. The three most important issues among these are energy efficiency, quality of service and security management. To get the best possible results in one or more of these issues in wireless sensor networks optimization is necessary. Furthermore, in number of applications (e.g., body area sensor networks, vehicular ad hoc networks) these issues might conflict and require a trade-off amongst them. Due to the high energy consumption and data processing requirements, the use of classical algorithms has historically been disregarded. In this context contemporary researchers started using bio-mimetic strategy-based optimization techniques in the field of wireless sensor networks. These techniques are diverse and involve many different optimization algorithms. As far as we know, most existing works tend to focus only on optimization of one specific issue of the three mentioned above. It is high time that these individual efforts are put into perspective and a more holistic view is taken. In this paper we take a step in that direction by presenting a survey of the literature in the area of wireless sensor network optimization concentrating especially on the three most widely used bio-mimetic algorithms, namely, particle swarm optimization, ant colony optimization and genetic algorithm. In addition, to stimulate new research and development interests in this field, open research issues, challenges and future research directions are highlighted. PMID:24368702

Frito-Lay North America/NREL CRADA: Cooperative Research and Development Final Report, CRADA Number CRD-06-176

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

Walker, A.

2013-06-01

Frito Lay North America (FLNA) requires technical assistance for the evaluation and implementation of renewable energy and energy efficiency projects in production facilities and distribution centers across North America. Services provided by NREL do not compete with those available in the private sector, but rather provide FLNA with expertise to create opportunities for the private sector renewable/efficiency industries and to inform FLNA decision making regarding cost-effective projects. Services include: identifying the most cost-effective project locations based on renewable energy resource data, utility data, incentives and other parameters affecting projects; assistance with feasibility studies; procurement specifications; design reviews; and other servicesmore » to support FNLA in improving resource efficiency at facilities. This Cooperative Research and Development Agreement (CRADA) establishes the terms and conditions under which FLNA may access capabilities unique to the laboratory and required by FLNA. Each subsequent task issued under this umbrella agreement would include a scope-of-work, budget, schedule, and provisions for intellectual property specific to that task.« less

Wireless electricity (Power) transmission using solar based power satellite technology

NASA Astrophysics Data System (ADS)

Maqsood, M.; Nauman Nasir, M.

2013-06-01

In the near future due to extensive use of energy, limited supply of resources and the pollution in environment from present resources e.g. (wood, coal, fossil fuel) etc, alternative sources of energy and new ways to generate energy which are efficient, cost effective and produce minimum losses are of great concern. Wireless electricity (Power) transmission (WET) has become a focal point as research point of view and nowadays lies at top 10 future hot burning technologies that are under research these days. In this paper, we present the concept of transmitting power wirelessly to reduce transmission and distribution losses. The wired distribution losses are 70 - 75% efficient. We cannot imagine the world without electric power which is efficient, cost effective and produce minimum losses is of great concern. This paper tells us the benefits of using WET technology specially by using Solar based Power satellites (SBPS) and also focuses that how we make electric system cost effective, optimized and well organized. Moreover, attempts are made to highlight future issues so as to index some emerging solutions.

Nanoscale control of energy and matter in plasma-surface interactions: towards energy-efficient nanotech

NASA Astrophysics Data System (ADS)

Ostrikov, Kostya

2010-11-01

This presentation focuses on the plasma issues related to the solution of the grand challenge of directing energy and matter at nanoscales. This ability is critical for the renewable energy and energy-efficient technologies for sustainable future development. It will be discussed how to use environmentally and human health benign non-equilibrium plasma-solid systems and control the elementary processes of plasma-surface interactions to direct the fluxes of energy and matter at multiple temporal and spatial scales. In turn, this makes it possible to achieve the deterministic synthesis of self- organised arrays of metastable nanostructures in the size range beyond the reach of the present-day nanofabrication. Such structures have tantalising prospects to enhance performance of nanomaterials in virtually any area of human activity yet remain almost inaccessible because the Nature's energy minimisation rules allow only a small number of stable equilibrium states. By using precisely controlled and kinetically fast nanoscale transfer of energy and matter under non-equilibrium conditions and harnessing numerous plasma- specific controls of species creation, delivery to the surface, nucleation and large-scale self-organisation of nuclei and nanostructures, the arrays of metastable nanostructures can be created, arranged, stabilised, and further processed to meet the specific requirements of the envisaged applications. These approaches will eventually lead to faster, unprecedentedly- clean, human-health-friendly, and energy-efficient nanoscale synthesis and processing technologies for the next-generation renewable energy and light sources, biomedical devices, information and communication systems, as well as advanced functional materials for applications ranging from basic food, water, health and clean environment needs to national security and space missions.

CO2 - The Canary in the Energy Efficiency Coal Mine

NASA Astrophysics Data System (ADS)

Somssich, Peter

2011-04-01

While much of the discussion surrounding CO2 is focused on its role as a GHG (green house gas) and its affect on Climate Change, CO2 can also be viewed as an indicator for reductions in fossil fuel use and increased energy efficiency. Much as the canary in a mine was used to warn miners of unsafe health conditions in a mine, CO2 can be seen as allowing us to effectively track progress towards energy efficiency and sustainability. Such an effort can best be achieved by either a Carbon Tax or a Cap and Trade system which was highly effective as part of the 1992 Clean Air Act, contributing to a significant reduction of SO2 and acid rain. A similar attempt has been made using the 1997 Kyoto Protocol to reduce carbon emissions. The mechanisms of how this treaty was intended to work will be explained, and examples will be given, both in the USA and Europe, of how the protocol was used to reduce energy consumption and energy dependence, while also reducing CO2 emissions. Regardless of how strong an impact CO2 reduction may have for Climate Change issues, a reduction of CO2 is guaranteed to produce energy benefits, monetary benefits and can even enhance national security. For all of these reasons, we need the CO2 canary.

None

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

Traylor, T.D.; Hicks, S.C.

1994-03-01

Transportation Energy Research announces on a monthly basis the current worldwide research and development information available on energy-efficient, environmentally sound transportation technologies. Its purpose is to enhance the technology transfer efforts of the Department of Energy. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange or government-to-government agreements. The DOE Office of Transportation Technologies (OTT) managesmore » federal R&D programs aimed at improving transportation-sector energy efficiency. OTT currently supports activities in four major program areas: Electric and Hybrid Vehicles; Advanced Propulsion Systems; and magnetic levitation technology; Advanced Materials. DOE and DOE contractors can obtain copies for $4.00 per issue by using VISA, MasterCard, or OSTI deposit accounts. Contact the Office of Scientific and Technical Information, P.O. Box 62, Oak Ridge, TN 37831, Attention: Information Services. For further information, call (615) 576-8401. Public availability is by subscription from the US Department of Commerce, Technology Administration, National Technical Information Service, Springfield, VA 22161. Order PB94-900900.« less

Centre for Education, Training, & Research in Renewable Energy and Energy Efficiency (CETREE) of Malaysia: Educating the Nation

NASA Astrophysics Data System (ADS)

Ibrahim, Kamarulazizi; Hilme, Khairur Rahim Ahmad

2007-10-01

Centre for Education, Training, and Research in Renewable Energy and Energy Efficiency (CETREE), was established in the year 2000, in Universiti Sains Malaysia (USM). CETREE is a not-for-profit organization that was part of the Malaysian Government's continuous effort in promoting sustainable development. The centre's main task is to tackle issues and problems that are slowing the potential growth of RE & EE utilizations in Malaysia. CETREE and the Government of Malaysia, with funding and supports from Danish International Development Assistance (DANIDA) and USM, has been working together closely in applying trans-disciplinary educational methods and approaches for the teaching of RE & EE that are compatible with Malaysian. Through association with various entities such as Energy Centre of Malaysia (PTM), Energy Commission of Malaysia (ST), Malaysia Electricity Supply Industry Trust Account (MESITA); CETREE was able to successfully promote sustainable development through education and training. Significant accomplishments made by CETREE include introducing RE and EE as part of Malaysian secondary schools and universities education; conducting energy related courses for professionals; and generating awareness via campaign in the mass media and CETREE's mobile-exhibition-unit road-tour.

Driving Demand for Home Energy Improvements: Motivating residential customers to invest in comprehensive upgrades that eliminate energy waste, avoid high utility bills, and spur the economy

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

Fuller, Merrian C.

Policy makers and program designers in the U.S. and abroad are deeply concerned with the question of how to scale up energy efficiency to a level that is commensurate both to the scale of the energy and climate challenges we face, and to the potential for energy savings that has been touted for decades. When policy makers ask what energy efficiency can do, the answers usually revolve around the technical and economic potential of energy efficiency - they rarely hone in on the element of energy demand that matters most for changing energy usage in existing homes: the consumer. Amore » growing literature is concerned with the behavioral underpinnings of energy consumption. We examine a narrower, related subject: How can millions of Americans be persuaded to divert valued time and resources into upgrading their homes to eliminate energy waste, avoid high utility bills, and spur the economy? With hundreds of millions of public dollars flowing into incentives, workforce training, and other initiatives to support comprehensive home energy improvements, it makes sense to review the history of these programs and begin gleaning best practices for encouraging comprehensive home energy improvements. Looking across 30 years of energy efficiency programs that targeted the residential market, many of the same issues that confronted past program administrators are relevant today: How do we cost-effectively motivate customers to take action? Who can we partner with to increase program participation? How do we get residential efficiency programs to scale? While there is no proven formula - and only limited success to date with reliably motivating large numbers of Americans to invest in comprehensive home energy improvements, especially if they are being asked to pay for a majority of the improvement costs - there is a rich and varied history of experiences that new programs can draw upon. Our primary audiences are policy makers and program designers - especially those that are relatively new to the field, such as the over 2,000 towns, cities, states, and regions who are recipients of American Reinvestment and Recovery Act funds for clean energy programs. This report synthesizes lessons from first generation programs, highlights emerging best practices, and suggests methods and approaches to use in designing, implementing, and evaluating these programs. We examined 14 residential energy efficiency programs, conducted an extensive literature review, interviewed industry experts, and surveyed residential contractors to draw out these lessons.« less

State Roles in the Global Climate Change Issue.

NASA Astrophysics Data System (ADS)

Changnon, Stanley A.

1995-02-01

Events in 1988 helped focus the attention of several states on the global climate change issue. Consequently, the National Governors' Association conducted an assessment in 1989 and recommended various actions. By 1994, 22 states have enacted laws or regulations and/or established research programs addressing climate change. Most of these "no regrets" actions are set up to conserve energy or improve energy efficiency and also to reduce greenhouse gas emissions. Illinois has adopted an even broader program by 1) establishing a Global Climate Change Office to foster research and provide information and 2) forming a task force to address a wide array of issues including state input to federal policies such as the Clinton administration's 1993 Climate Change Action Plan and to the research dimensions of the U.S. Global Climate Change Research Program. The Illinois program calls for increased attention to studies of regional impacts, including integrated assessments, and to research addressing means to adapt to future climate change. These various state efforts to date help show the direction of policy development and should be useful to those grappling with these issues.

Industrial wastewater treatment with a bioelectrochemical process: assessment of depuration efficiency and energy production.

PubMed

Molognoni, Daniele; Chiarolla, Stefania; Cecconet, Daniele; Callegari, Arianna; Capodaglio, Andrea G

2018-01-01

Development of renewable energy sources, efficient industrial processes, energy/chemicals recovery from wastes are research issues that are quite contemporary. Bioelectrochemical processes represent an eco-innovative technology for energy and resources recovery from both domestic and industrial wastewaters. The current study was conducted to: (i) assess bioelectrochemical treatability of industrial (dairy) wastewater by microbial fuel cells (MFCs); (ii) determine the effects of the applied organic loading rate (OLR) on MFC performance; (iii) identify factors responsible for reactor energy recovery losses (i.e. overpotentials). For this purpose, an MFC was built and continuously operated for 72 days, during which the anodic chamber was fed with dairy wastewater and the cathodic chamber with an aerated mineral solution. The study demonstrated that industrial effluents from agrifood facilities can be treated by bioelectrochemical systems (BESs) with >85% (average) organic matter removal, recovering power at an observed maximum density of 27 W m -3 . Outcomes were better than in previous (shorter) analogous experiences, and demonstrate that this type of process could be successfully used for dairy wastewater with several advantages.

Robust Networking Architecture and Secure Communication Scheme for Heterogeneous Wireless Sensor Networks

ERIC Educational Resources Information Center

McNeal, McKenzie, III.

2012-01-01

Current networking architectures and communication protocols used for Wireless Sensor Networks (WSNs) have been designed to be energy efficient, low latency, and long network lifetime. One major issue that must be addressed is the security in data communication. Due to the limited capabilities of low cost and small sized sensor nodes, designing…

Electricity's Future: The Shift to Efficiency and Small-Scale Power. Worldwatch Paper 61.

ERIC Educational Resources Information Center

Flavin, Christopher

Electricity, which has largely supplanted oil as the most controversial energy issue of the 1980s, is at the center of some of the world's bitterest economic and environmental controversies. Soaring costs, high interest rates, and environmental damage caused by large power plants have wreaked havoc on the once booming electricity industry.…

78 FR 79579 - Energy Conservation Program: Alternative Efficiency Determination Methods, Basic Model Definition...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-31

... Working Group agreed on a one- sided 5 percent tolerance when comparing the validation test results to the... one DOE representative. 78 FR 22431. The members of the Working Group were selected to ensure a broad... Issues 1. Pre-Approval The Working Group unanimously recommended that DOE not require pre- approval for...

The future of nuclear power: The role of the IFR

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

Wilson, R.

1995-12-31

The author is in favor of nuclear energy for three major reasons: (1) a nuclear power station emits no particulates or sulfur; (2) a nuclear power station emits no carbon dioxide and therefore does not contribute (appreciably) to the possibility of global warming which is a major environmental issue of this century; (3) nuclear energy offers the opportunity to have an energy supply sustainable for the next hundred thousands years, and is the only supply presently known to be able to do so at a reasonable cost. He notes that at Rio de Janeiro, the USA joined other countries inmore » calling for an approach to an indefinitely sustainable future. Alas, they were not bold or honest enough to state that using nuclear power, combined with considerable increase in energy efficiency and prudent use of renewables, is the only known way of achieving one other than massive population reduction or poverty. It is unlikely that improved energy efficiency can do the job alone. If the first two were the only issues, ordinary light water reactors would be adequate. One would not need the breeder reactor. But unless huge quantities of high quality uranium are found, or a cheap way of extracting it from seawater, one will need to have a way of using the uranium 238 or thorium. This is the role of this meeting. The author arrives at a set of criteria for a breeder reactor system: (1) it must be safe (secure against major accidents); (2) the system must be proliferation resistant; (3) the cost of the produced electricity must be competitive with other sources of energy--with perhaps a small margin for environmental advantage; (4) it must be capable of rapid expansion if and when needed.« less

Multiscale modeling and experimental interpretation of perovskite oxide materials in thermochemical energy storage and conversion for application in concentrating solar power

NASA Astrophysics Data System (ADS)

Albrecht, Kevin J.

Decarbonization of the electric grid is fundamentally limited by the intermittency of renewable resources such as wind and solar. Therefore, energy storage will play a significant role in the future of grid-scale energy generation to overcome the intermittency issues. For this reason, concentrating solar power (CSP) plants have been a renewable energy generation technology of interest due to their ability to participate in cost effective and efficient thermal energy storage. However, the ability to dynamically dispatch a CSP plant to meet energy demands is currently limited by the large quantities of sensible thermal energy storage material needed in a molten salt plant. Perovskite oxides have been suggested as a thermochemical energy storage material to enhance the energy storage capabilities of particle-based CSP plants, which combine sensible and chemical modes of energy storage. In this dissertation, computational models are used to establish the thermochemical energy storage potential of select perovskite compositions, identify system configurations that promote high values of energy storage and solar-to-electric efficiency, assess the kinetic and transport limitation of the chemical mode of energy storage, and create receiver and reoxidation reactor models capable of aiding in component design. A methodology for determining perovskite thermochemical energy storage potential is developed based on point defect models to represent perovskite non-stoichiometry as a function of temperature and gas phase oxygen partial pressure. The thermodynamic parameters necessary for the model are extracted from non-stoichiometry measurements by fitting the model using an optimization routine. The procedure is demonstrated for Ca0.9Sr0.1MnO 3-d which displayed combined energy storage values of 705.7 kJ/kg -1 by cycling between 773 K and 0.21 bar oxygen to 1173 K and 10 -4 bar oxygen. Thermodynamic system-level models capable of exploiting perovskite redox chemistry for energy storage in CSP plants are presented. Comparisons of sweep gas and vacuum pumping reduction as well as hot storage conditions indicate that solar-to-electric efficiencies are higher for sweep gas reduction system at equivalent values of energy storage if the energy parasitics of commercially available devices are considered. However, if vacuum pump efficiency between 15% and 30% can be achieved, the reduction methods will be approximately equal. Reducing condition oxygen partial pressures below 10-3 bar for sweep gas reduction and 10-2 bar for vacuum pumping reduction result in large electrical parasitics, which significantly reduce solar-to-electric efficiency. A model based interpretation of experimental measurements made for perovskite redox cycling using sweep gas in a packed bed is presented. The model indicates that long reduction times for equilibrating perovskites with low oxygen partial pressure sweep gas, compared to reoxidation, are primarily due to the oxygen carrying capacity of high purity sweep gas and not surface kinetic limitations. Therefore, achieving rapid reduction in the limited receiver residence time will be controlled by the quantity of sweep gas introduced. Effective kinetic parameters considering surface reaction and radial particle diffusion are fit to the experimental data. Variable order rate expressions without significant particle radial diffusion limitations are shown to be capable of representing the reduction and oxidation data. Modeling of a particle reduction receiver using continuous flow of perovskite solid and sweep gas in counter-flow configuration has identified issues with managing the oxygen evolved by the solid as well as sweep gas flow rates. Introducing sweep gas quantities necessary for equilibrating the solid with oxygen partial pressures below 10-2 are shown to result in gas phase velocities above the entrainment velocity of 500 um particles. Receiver designs with considerations for gas management are investigated and the results indicate that degrees of reduction corresponding to only oxygen partial pressures of 10-2 bar are attained. Numerical investigation into perovskite thermochemical energy storage indicates that achieving high levels of reduction through sweep gas or vacuum pumping to lower gas phase oxygen partial pressure below 10-2 bar display issues with parasitic energy consumption and gas phase management. Therefore, focus on material development should place a premium on thermal reduction and reduction by shifting oxygen partial pressure between ambient and 10-2 bar. Such a material would enable the development of a system with high solar-to-electric efficiencies and degrees of reduction which are attainable in realistic component geometries.

Sustainability of uranium mining and milling: toward quantifying resources and eco-efficiency.

PubMed

Mudd, Gavin M; Diesendorf, Mark

2008-04-01

The mining of uranium has long been a controversial public issue, and a renewed debate has emerged on the potential for nuclear power to help mitigate against climate change. The central thesis of pro-nuclear advocates is the lower carbon intensity of nuclear energy compared to fossil fuels, although there remains very little detailed analysis of the true carbon costs of nuclear energy. In this paper, we compile and analyze a range of data on uranium mining and milling, including uranium resources as well as sustainability metrics such as energy and water consumption and carbon emissions with respect to uranium production-arguably the first time for modern projects. The extent of economically recoverable uranium resources is clearly linked to exploration, technology, and economics but also inextricably to environmental costs such as energy/water/chemicals consumption, greenhouse gas emissions, and social issues. Overall, the data clearly show the sensitivity of sustainability assessments to the ore grade of the uranium deposit being mined and that significant gaps remain in complete sustainability reporting and accounting. This paper is a case study of the energy, water, and carbon costs of uranium mining and milling within the context of the nuclear energy chain.

A strategy to minimize the energy offset in carrier injection from excited dyes to inorganic semiconductors for efficient dye-sensitized solar energy conversion.

PubMed

Fujisawa, Jun-Ichi; Osawa, Ayumi; Hanaya, Minoru

2016-08-10

Photoinduced carrier injection from dyes to inorganic semiconductors is a crucial process in various dye-sensitized solar energy conversions such as photovoltaics and photocatalysis. It has been reported that an energy offset larger than 0.2-0.3 eV (threshold value) is required for efficient electron injection from excited dyes to metal-oxide semiconductors such as titanium dioxide (TiO2). Because the energy offset directly causes loss in the potential of injected electrons, it is a crucial issue to minimize the energy offset for efficient solar energy conversions. However, a fundamental understanding of the energy offset, especially the threshold value, has not been obtained yet. In this paper, we report the origin of the threshold value of the energy offset, solving the long-standing questions of why such a large energy offset is necessary for the electron injection and which factors govern the threshold value, and suggest a strategy to minimize the threshold value. The threshold value is determined by the sum of two reorganization energies in one-electron reduction of semiconductors and typically-used donor-acceptor (D-A) dyes. In fact, the estimated values (0.21-0.31 eV) for several D-A dyes are in good agreement with the threshold value, supporting our conclusion. In addition, our results reveal that the threshold value is possible to be reduced by enlarging the π-conjugated system of the acceptor moiety in dyes and enhancing its structural rigidity. Furthermore, we extend the analysis to hole injection from excited dyes to semiconductors. In this case, the threshold value is given by the sum of two reorganization energies in one-electron oxidation of semiconductors and D-A dyes.

Cross Layer Design for Optimizing Transmission Reliability, Energy Efficiency, and Lifetime in Body Sensor Networks.

PubMed

Chen, Xi; Xu, Yixuan; Liu, Anfeng

2017-04-19

High transmission reliability, energy efficiency, and long lifetime are pivotal issues for wireless body area networks (WBANs. However, these performance metrics are not independent of each other, making it hard to obtain overall improvements through optimizing one single aspect. Therefore, a Cross Layer Design Optimal (CLDO) scheme is proposed to simultaneously optimize transmission reliability, energy efficiency, and lifetime of WBANs from several layers. Firstly, due to the fact that the transmission power of nodes directly influences the reliability of links, the optimized transmission power of different nodes is deduced, which is able to maximize energy efficiency in theory under the premise that requirements on delay and jitter are fulfilled. Secondly, a relay decision algorithm is proposed to choose optimized relay nodes. Using this algorithm, nodes will choose relay nodes that ensure a balance of network energy consumption, provided that all nodes transmit with optimized transmission power and the same packet size. Thirdly, the energy consumption of nodes is still unbalanced even with optimized transmission power because of their different locations in the topology of the network. In addition, packet size also has an impact on final performance metrics. Therefore, a synthesized cross layer method for optimization is proposed. With this method, the transmission power of nodes with more residual energy will be enhanced while suitable packet size is determined for different links in the network, leading to further improvements in the WBAN system. Both our comprehensive theoretical analysis and experimental results indicate that the performance of our proposed scheme is better than reported in previous studies. Relative to the relay selection and power control game (RSPCG) scheme, the CLDO scheme can enhance transmission reliability by more than 44.6% and prolong the lifetime by as much as 33.2%.

Cross Layer Design for Optimizing Transmission Reliability, Energy Efficiency, and Lifetime in Body Sensor Networks

PubMed Central

Chen, Xi; Xu, Yixuan; Liu, Anfeng

2017-01-01

High transmission reliability, energy efficiency, and long lifetime are pivotal issues for wireless body area networks (WBANs). However, these performance metrics are not independent of each other, making it hard to obtain overall improvements through optimizing one single aspect. Therefore, a Cross Layer Design Optimal (CLDO) scheme is proposed to simultaneously optimize transmission reliability, energy efficiency, and lifetime of WBANs from several layers. Firstly, due to the fact that the transmission power of nodes directly influences the reliability of links, the optimized transmission power of different nodes is deduced, which is able to maximize energy efficiency in theory under the premise that requirements on delay and jitter are fulfilled. Secondly, a relay decision algorithm is proposed to choose optimized relay nodes. Using this algorithm, nodes will choose relay nodes that ensure a balance of network energy consumption, provided that all nodes transmit with optimized transmission power and the same packet size. Thirdly, the energy consumption of nodes is still unbalanced even with optimized transmission power because of their different locations in the topology of the network. In addition, packet size also has an impact on final performance metrics. Therefore, a synthesized cross layer method for optimization is proposed. With this method, the transmission power of nodes with more residual energy will be enhanced while suitable packet size is determined for different links in the network, leading to further improvements in the WBAN system. Both our comprehensive theoretical analysis and experimental results indicate that the performance of our proposed scheme is better than reported in previous studies. Relative to the relay selection and power control game (RSPCG) scheme, the CLDO scheme can enhance transmission reliability by more than 44.6% and prolong the lifetime by as much as 33.2%. PMID:28422062

Megawatt-class free-electron laser concept for shipboard self-defense

NASA Astrophysics Data System (ADS)

Todd, Alan M. M.; Colson, William B.; Neil, George R.

1997-05-01

An efficient MW-class free electron laser (FEL) directed energy weapon (DEW) system holds promise for satisfying shipboard self-defense (SSD) requirements on future generations of Navy vessels because of the potential for high- power operation and the accessibility to all IR wavelengths. In order to meet shipboard packaging and prime power constraints, the power efficiency and high real-estate gradient achievable in a FEL driven by a superconducting rf accelerator is attractive. Configuration options and the key development issues for such a system are described.

Learning energy literacy concepts from energy-efficient homes

NASA Astrophysics Data System (ADS)

Paige, Frederick Eugene

The purpose of this study is to understand ways that occupants' and visitors' interaction with energy efficient home design affects Energy Literacy. Using a case study approach including interviews, surveys, and observations, I examined the potential for affordable energy efficient homes in the Greenville South Carolina area to "teach" concepts from an Energy Literacy framework developed by dozens of educational partners and federal agencies that comprise the U.S. Global Change Research Program Partners. I paid particular attention to concepts from the framework that are transferable to energy decisions beyond a home's walls. My research reveals ways that interaction with high efficiency homes can effect understanding of the following Energy Literacy concepts: human use of energy is subject to limits and constraints, conservation is one way to manage energy resources, electricity is generated in multiple ways, social and technological innovations effect the amount of energy used by society, and energy use can be calculated and monitored. Examples from my case studies show how the at-home examples can make lessons on energy more personally relevant, easy to understand, and applicable. Specifically, I found that: • Home occupants learn the limits of energy in relation to the concrete and constricting costs associated with their consumption. • Heating and cooling techniques showcase the limits and constraints on different sources of energy. • Relatable systems make it easier to understand energy's limits and constraints. • Indistinct and distant power utilities allow consumers to overlook the root of electricity sources. • Visible examples of electricity generation systems make it clear that electricity is generated in multiple ways. • Small and interactive may mean inefficient electricity generation, but efficient energy education. • Perceptions of expense and complexity create a disconnect between residential energy consumers and renewable electricity generation. • Utility bill limits and constraints exemplify the ability to conserve energy resources. • Replicable examples teach lessons on conservation. • Via an understanding of the water-energy nexus, water conservation lessons transfer to energy saving lessons. • Passive design exemplifies how a shift in thinking can conserve energy resources through informed efficient decision-making. • Societal shifts in energy consumption are evident at home. • Efficient homes provide applicable examples of social and technological innovations. • The home is the environment in which memorable lessons on energy are passed through cultures. • Home energy consumption comparisons are a popular and effective social innovation, but people have mixed emotions about their usefulness. • A utility bill communicates that utility companies are monitoring energy use to calculate cost. • Interactivity enhances feedback from energy monitors. • Calculating and monitoring energy use is perceived as a complex mathematical process. • Energy consumption feedback at the appliance level is desired to inform decisions. • There is a separation between personal energy monitoring and public monitoring. Implications of this research are that an energy literate society will have the knowledge that is a prerequisite for the motivation to address energy and climate issues. Educators, policy makers, engineers, and designers all play a role in creating a built environment that encourages energy saving behavior.

Technology Solutions Case Study: Guidance on Taped Insulating Sheathing Drainage Planes

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

None

The energy efficiency-based financial benefits of adding exterior insulation are well accepted by the building industry, and using exterior insulation as the drainage plane is the next logical step. This case study focuses on the field implementation of taped board insulation as the drainage plane in both new and retrofit residential applications, and provides information and recommendations for insulation contractors, general contractors, builders, remodelers, mechanical contractors, and homeowners. The order of work completed during home construction and retrofit improvements is important. Health and safety issues must be addressed first and are more important than durability issues, and durability issues aremore » more important than saving energy. Three significant items are required to make taped insulating sheathing a simple, long term, and durable drainage plane: first, horizontal joints should be limited or eliminated wherever possible; where a horizontal joint exists, use superior materials; and, frequent installation inspection and regular trade training are required to maintain proper installation.« less

Thermal hydraulic behavior and efficiency analysis of an all-vanadium redox flow battery

NASA Astrophysics Data System (ADS)

Xiong, Binyu; Zhao, Jiyun; Tseng, K. J.; Skyllas-Kazacos, Maria; Lim, Tuti Mariana; Zhang, Yu

2013-11-01

Vanadium redox flow batteries (VRBs) are very competitive for large-capacity energy storage in power grids and in smart buildings due to low maintenance costs, high design flexibility, and long cycle life. Thermal hydraulic modeling of VRB energy storage systems is an important issue and temperature has remarkable impacts on the battery efficiency, the lifetime of material and the stability of the electrolytes. In this paper, a lumped model including auxiliary pump effect is developed to investigate the VRB temperature responses under different operating and surrounding environmental conditions. The impact of electrolyte flow rate and temperature on the battery electrical characteristics and efficiencies are also investigated. A one kilowatt VRB system is selected to conduct numerical simulations. The thermal hydraulic model is benchmarked with experimental data and good agreement is found. Simulation results show that pump power is sensitive to hydraulic design and flow rates. The temperature in the stack and tanks rises up about 10 °C under normal operating conditions for the stack design and electrolyte volume selected. An optimal flow rate of around 90 cm3 s-1 is obtained for the proposed battery configuration to maximize battery efficiency. The models developed in this paper can also be used for the development of a battery control strategy to achieve satisfactory thermal hydraulic performance and maximize energy efficiency.

Entropy, pumped-storage and energy system finance

NASA Astrophysics Data System (ADS)

Karakatsanis, Georgios

2015-04-01

Pumped-storage holds a key role for integrating renewable energy units with non-renewable fuel plants into large-scale energy systems of electricity output. An emerging issue is the development of financial engineering models with physical basis to systematically fund energy system efficiency improvements across its operation. A fundamental physically-based economic concept is the Scarcity Rent; which concerns the pricing of a natural resource's scarcity. Specifically, the scarcity rent comprises a fraction of a depleting resource's full price and accumulates to fund its more efficient future use. In an integrated energy system, scarcity rents derive from various resources and can be deposited to a pooled fund to finance the energy system's overall efficiency increase; allowing it to benefit from economies of scale. With pumped-storage incorporated to the system, water upgrades to a hub resource, in which the scarcity rents of all connected energy sources are denominated to. However, as available water for electricity generation or storage is also limited, a scarcity rent upon it is also imposed. It is suggested that scarcity rent generation is reducible to three (3) main factors, incorporating uncertainty: (1) water's natural renewability, (2) the energy system's intermittent components and (3) base-load prediction deviations from actual loads. For that purpose, the concept of entropy is used in order to measure the energy system's overall uncertainty; hence pumped-storage intensity requirements and generated water scarcity rents. Keywords: pumped-storage, integration, energy systems, financial engineering, physical basis, Scarcity Rent, pooled fund, economies of scale, hub resource, uncertainty, entropy Acknowledgement: This research was funded by the Greek General Secretariat for Research and Technology through the research project Combined REnewable Systems for Sustainable ENergy DevelOpment (CRESSENDO; grant number 5145)

High-efficiency power production from natural gas with carbon capture

NASA Astrophysics Data System (ADS)

Adams, Thomas A.; Barton, Paul I.

A unique electricity generation process uses natural gas and solid oxide fuel cells at high electrical efficiency (74%HHV) and zero atmospheric emissions. The process contains a steam reformer heat-integrated with the fuel cells to provide the heat necessary for reforming. The fuel cells are powered with H 2 and avoid carbon deposition issues. 100% CO 2 capture is achieved downstream of the fuel cells with very little energy penalty using a multi-stage flash cascade process, where high-purity water is produced as a side product. Alternative reforming techniques such as CO 2 reforming, autothermal reforming, and partial oxidation are considered. The capital and energy costs of the proposed process are considered to determine the levelized cost of electricity, which is low when compared to other similar carbon capture-enabled processes.

Towards greener environment: Energy efficient pathways for the transportation sector in Malaysia

NASA Astrophysics Data System (ADS)

Indati, M. S.; Ghate, A. T.; Leong, Y. P.

2013-06-01

Transportation sector is the second most energy consuming sector after industrial sector, accounting for 40% of total energy consumption in Malaysia. The transportation sector is one of the most energy intensive sectors in the country and relies primarily on petroleum products, which in total account for nearly 98% of the total consumption in the sector. Since it is heavily reliant on petroleum based fuels, the sector contributes significantly to the greenhouse gas (GHG) emissions. The need to reduce the greenhouse gas emission is paramount as Malaysia at Conference of the Parties (COP15) pledged to reduce its carbon intensity by 40% by 2020 from 2005 level subject to availability of technology and finance. Transport sector will be among the first sectors that need to be addressed to achieve this goal, as two-thirds of the emissions come from fuel combustion in transport sector. This paper will analyse the factors influencing the transport sector's growth and energy consumption trends and discuss the key issues and challenges for greener environment and sustainable transportation in Malaysia. The paper will also discuss the policy and strategic options aimed towards energy efficient pathways in Malaysia.

Application of Electric Double-layer Capacitors for Energy Storage on Electric Railway

NASA Astrophysics Data System (ADS)

Hase, Shin-Ichi; Konishi, Takeshi; Okui, Akinobu; Nakamichi, Yoshinobu; Nara, Hidetaka; Uemura, Tadashi

The methods to stabilize power sources, which are the measures against voltage drop, power loading fluctuation, regeneration power lapse and so on, have been important issues in DC feeding circuits. Therefore, an energy storage medium that uses power efficiently and reduces above-mentioned problems is much concerned about. In recent years, development of energy storage medium is remarkable for drive-power supplies of electric vehicles. A number of applications of energy storage, for instance, battery and flywheel, have been investigated so far. A large-scale electric double-layer capacitor which is rapidly charged and discharged and offers long life, maintenance-free, low pollution and high efficiency, has been developed in wide range. We have compared the ability to charge batteries and electric double-layer capacitors. Therefore, we carried out fundamental studies about electric double-layer capacitors and its control. And we produced a prototype of energy storage for the DC electric railway system that consists of electric double-layer capacitors, diode bridge rectifiers, chopper system and PWM converters. From the charge and discharge tests of the prototype, useful information was obtained. This paper describes its characteristics and experimental results of energy storage system.

A multiple perspective modeling and simulation approach for renewable energy policy evaluation

NASA Astrophysics Data System (ADS)

Alyamani, Talal M.

Environmental issues and reliance on fossil fuel sources, including coal, oil, and natural gas, are the two most common energy issues that are currently faced by the United States (U.S.). Incorporation of renewable energy sources, a non-economical option in electricity generation compared to conventional sources that burn fossil fuels, single handedly promises a viable solution for both of these issues. Several energy policies have concordantly been suggested to reduce the financial burden of adopting renewable energy technologies and make such technologies competitive with conventional sources throughout the U.S. This study presents a modeling and analysis approach for comprehensive evaluation of renewable energy policies with respect to their benefits to various related stakeholders--customers, utilities, governmental and environmental agencies--where the debilitating impacts, advantages, and disadvantages of such policies can be assessed and quantified at the state level. In this work, a novel simulation framework is presented to help policymakers promptly assess and evaluate policies from different perspectives of its stakeholders. The proposed framework is composed of four modules: 1) a database that collates the economic, operational, and environmental data; 2) elucidation of policy, which devises the policy for the simulation model; 3) a preliminary analysis, which makes predictions for consumption, supply, and prices; and 4) a simulation model. After the validity of the proposed framework is demonstrated, a series of planned Florida and Texas renewable energy policies are implemented into the presented framework as case studies. Two solar and one energy efficiency programs are selected as part of the Florida case study. A utility rebate and federal tax credit programs are selected as part of the Texas case study. The results obtained from the simulation and conclusions drawn on the assessment of current energy policies are presented with respect to the conflicting objectives of different stakeholders.

Energy Star program benefits Con Edison

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

NONE

Impressed with savings in energy costs achieved after upgrading the lighting and air conditioning systems at its Manhattan headquarters, Home Box Office (HBO) wanted to do more, James Flock, vice president for computer and office systems, contacted Con Edison Co. of New York in March 1991 to determine what the company could do to save money by reducing energy consumed by personal computers. Arthur Kressner, Con Edison Research and Development manager contacted industry organizations and manufacturers for advice, but was told only to shut off computers at night and on weekends. Kressner arranged a series of meetings with IBM andmore » the Electric Power Research Institute (EPRI) to discuss the issue, then approached the U.S. Environmental Protection Agency (EPA), which was designing a program to promote the introduction and use of energy-efficient office equipment. In 1992, the EPA announced the Energy Star program for PCs, enabling manufacturers to display the Energy Star logo on machines meeting program criteria, including the ability to enter a sleep mode in which neither the computer nor monitor consume more than 30 W or electricity. Industry experts estimate national energy consumption by office equipment could double by the year 2000, but Energy Star equipment is expected to improve efficiency and help maintain electric loads.« less

Resource use efficiency of closed plant production system with artificial light: Concept, estimation and application to plant factory

PubMed Central

KOZAI, Toyoki

2013-01-01

Extensive research has recently been conducted on plant factory with artificial light, which is one type of closed plant production system (CPPS) consisting of a thermally insulated and airtight structure, a multi-tier system with lighting devices, air conditioners and fans, a CO2 supply unit, a nutrient solution supply unit, and an environment control unit. One of the research outcomes is the concept of resource use efficiency (RUE) of CPPS. This paper reviews the characteristics of the CPPS compared with those of the greenhouse, mainly from the viewpoint of RUE, which is defined as the ratio of the amount of the resource fixed or held in plants to the amount of the resource supplied to the CPPS. It is shown that the use efficiencies of water, CO2 and light energy are considerably higher in the CPPS than those in the greenhouse. On the other hand, there is much more room for improving the light and electric energy use efficiencies of CPPS. Challenging issues for CPPS and RUE are also discussed. PMID:24334509

Resource use efficiency of closed plant production system with artificial light: concept, estimation and application to plant factory.

PubMed

Kozai, Toyoki

2013-01-01

Extensive research has recently been conducted on plant factory with artificial light, which is one type of closed plant production system (CPPS) consisting of a thermally insulated and airtight structure, a multi-tier system with lighting devices, air conditioners and fans, a CO2 supply unit, a nutrient solution supply unit, and an environment control unit. One of the research outcomes is the concept of resource use efficiency (RUE) of CPPS.This paper reviews the characteristics of the CPPS compared with those of the greenhouse, mainly from the viewpoint of RUE, which is defined as the ratio of the amount of the resource fixed or held in plants to the amount of the resource supplied to the CPPS.It is shown that the use efficiencies of water, CO2 and light energy are considerably higher in the CPPS than those in the greenhouse. On the other hand, there is much more room for improving the light and electric energy use efficiencies of CPPS. Challenging issues for CPPS and RUE are also discussed.

Public sector energy management: A strategy for catalyzing energy efficiency in Malaysia

NASA Astrophysics Data System (ADS)

Roy, Anish Kumar

To date the public sector role in facilitating the transition to a sustainable energy future has been envisaged mainly from a regulatory perspective. In such a role, the public sector provides the push factors---enforcing regulations and providing incentives---to correct market imperfections that impede energy transitions. An alternative and complementary role of the public sector that is now gaining increasing attention is that of catalyzing energy transitions through public sector energy management initiatives. This dissertation offers a conceptual framework to rationalize such a role for the public sector by combining recent theories of sustainable energy transition and public management. In particular, the framework identifies innovative public management strategies (such as performance contracting and procurement) for effectively implementing sustainable energy projects in government facilities. The dissertation evaluates a model of sustainable public sector energy management for promoting energy efficiency in Malaysia. The public sector in Malaysia can be a major player in leading and catalyzing energy efficiency efforts as it is not only the largest and one of the most influential energy consumers, but it also plays a central role in setting national development strategy. The dissertation makes several recommendations on how a public sector energy management strategy can be implemented in Malaysia. The US Federal Energy Management Program (FEMP) is used as a practical model. The analysis, however, shows that in applying the FEMP model to the Malaysian context, there are a number of limitations that will have to be taken into consideration to enable a public sector energy management strategy to be effectively implemented. Overall the analysis of this dissertation contributes to a rethinking of the public sector role in sustainable energy development that can strengthen the sector's credibility both in terms of governance and institutional performance. In addition, it links theory with practice by offering a strategy that can effectively address critical issues arising from the energy-development-policy nexus of the sustainable energy development debate.

Management system to a photovoltaic panel based on the measurement of short-circuit currents

NASA Astrophysics Data System (ADS)

Dordescu, M.

2016-12-01

This article is devoted to fundamental issues arising from operation in terms of increased energy efficiency for photovoltaic panel (PV). By measuring the current from functioning cage determine the current value prescribed amount corresponding to maximum power point results obtained by requiring proof of pregnancy with this method are the maximum energy possible, thus justifying the usefulness of this process very simple and inexpensive to implement in practice. The proposed adjustment method is much simpler and more economical than conventional methods that rely on measuring power cut.

Chapter 19: HVAC Controls (DDC/EMS/BAS) 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.; Romberger, Jeff

The HVAC Controls Evaluation Protocol is designed to address evaluation issues for direct digital controls/energy management systems/building automation systems (DDC/EMS/BAS) that are installed to control heating, ventilation, and air-conditioning (HVAC) equipment in commercial and institutional buildings. (This chapter refers to the DDC/EMS/BAS measure as HVAC controls.) This protocol may also be applicable to industrial facilities such as clean rooms and labs, which have either significant HVAC equipment or spaces requiring special environmental conditions.

Energy Optimization on the Battlefield: How Integrating Energy Efficient Technologies at the Tactical Level Can Reduce Fuel Consumption and Lessen the Burden of Fuel Logistics

DTIC Science & Technology

2014-06-13

a kill zone. This also created maintenance issues including diesel soot buildup in the vehicles exhaust systems. Since it took three to four days to...cost savings when summed over the thousands of light fixtures used on bases and FOBs. Changing to LEDs in tents and installing motion sensors could...CFL systems. Motion sensors also aided in turning lights off when the tents 78 are not occupied. Both LEDs and motion sensors produced significant

Unlikely (but perfect) partners in the fight for the green energy and fair trade economy.

PubMed

Redmond, Fred

2009-01-01

A priority for the United Steelworkers the last several years has been its work with the Sierra Club as part of the Blue Green Alliance. By working with our unconventional allies, we impacted the most important general election in any of our lifetimes. Now, smart investments in renewable energy and fuel-efficient cars are cornerstones of the Obama administration's economic recovery plan. The other priority issue when we began the Blue Green Alliance was fair trade. It still is a priority.

Barriers to electric energy efficiency in Ghana

NASA Astrophysics Data System (ADS)

Berko, Joseph Kofi, Jr.

Development advocates argue that sustainable development strategies are the best means to permanently improve living standards in developing countries. Advocates' arguments are based on the technical, financial, and environmental advantages of sustainable development. However, they have not addressed the organizational and administrative decision-making issues which are key to successful implementation of sustainable development in developing countries. Using the Ghanaian electricity industry as a case study, this dissertation identifies and analyzes organizational structures, administrative mechanisms, and decision-maker viewpoints that critically affect the success of adoption and implementation of energy efficiency within a sustainable development framework. Utilizing semi-structured interviews in field research, decision-makers' perceptions of the pattern of the industry's development, causes of the electricity supply shortfall, and barriers to electricity-use efficiency were identified. Based on the initial findings, the study formulated a set of policy initiatives to establish support for energy use efficiency. In a second set of interviews, these policy suggestions were presented to some of the top decision-makers to elicit their reactions. According to the decision-makers, the electricity supply shortfall is due to rapid urbanization and increased industrial consumption as a result of the structural adjustment program, rural electrification, and the sudden release of suppressed loads. The study found a lack of initiative and collaboration among industry decision-makers, and a related divergence in decision-makers' concerns and viewpoints. Also, lacking are institutional support systems and knowledge of proven energy efficiency strategies and technologies. As a result, planning, and even the range of perceived solutions to choose from are supply-side oriented. The final chapter of the study presents implications of its findings and proposes that any implementation strategy will have to address the different decision-makers' concerns and viewpoints. These include the need for national policies to promote electric energy efficiency and institutional development to provide support, guidance and direction to an energy efficiency effort. It also proposes structural changes within the industry to reduce government influence by creating an independent regulatory board. Finally, it proposes the adoption of integrated resource planning strategies and changes in the supply-side dominated culture within the electric utilities.

Survey of Current and Next Generation Space Power Technologies

DTIC Science & Technology

2006-06-26

different thermodynamic cycles, such as the Brayton, Rankine, and Stirling cycles, alkali metal thermal electric converters ( AMTEC ) and thermionic...efficiencies @ 1700K. The primary issue with this system is the integration of the converter technology into the nuclear reactor core. AMTEC (static...Alkali metal thermal to electric converters ( AMTECs ) are thermally powered electrochemical concentration cells that convert heat energy directly to DC

Secure and Fair Cluster Head Selection Protocol for Enhancing Security in Mobile Ad Hoc Networks

PubMed Central

Paramasivan, B.; Kaliappan, M.

2014-01-01

Mobile ad hoc networks (MANETs) are wireless networks consisting of number of autonomous mobile devices temporarily interconnected into a network by wireless media. MANETs become one of the most prevalent areas of research in the recent years. Resource limitations, energy efficiency, scalability, and security are the great challenging issues in MANETs. Due to its deployment nature, MANETs are more vulnerable to malicious attack. The secure routing protocols perform very basic security related functions which are not sufficient to protect the network. In this paper, a secure and fair cluster head selection protocol (SFCP) is proposed which integrates security factors into the clustering approach for achieving attacker identification and classification. Byzantine agreement based cooperative technique is used for attacker identification and classification to make the network more attack resistant. SFCP used to solve this issue by making the nodes that are totally surrounded by malicious neighbors adjust dynamically their belief and disbelief thresholds. The proposed protocol selects the secure and energy efficient cluster head which acts as a local detector without imposing overhead to the clustering performance. SFCP is simulated in network simulator 2 and compared with two protocols including AODV and CBRP. PMID:25143986

Ship Trim Optimization: Assessment of Influence of Trim on Resistance of MOERI Container Ship

PubMed Central

Duan, Wenyang

2014-01-01

Environmental issues and rising fuel prices necessitate better energy efficiency in all sectors. Shipping industry is a stakeholder in environmental issues. Shipping industry is responsible for approximately 3% of global CO2 emissions, 14-15% of global NOX emissions, and 16% of global SOX emissions. Ship trim optimization has gained enormous momentum in recent years being an effective operational measure for better energy efficiency to reduce emissions. Ship trim optimization analysis has traditionally been done through tow-tank testing for a specific hullform. Computational techniques are increasingly popular in ship hydrodynamics applications. The purpose of this study is to present MOERI container ship (KCS) hull trim optimization by employing computational methods. KCS hull total resistances and trim and sinkage computed values, in even keel condition, are compared with experimental values and found in reasonable agreement. The agreement validates that mesh, boundary conditions, and solution techniques are correct. The same mesh, boundary conditions, and solution techniques are used to obtain resistance values in different trim conditions at Fn = 0.2274. Based on attained results, optimum trim is suggested. This research serves as foundation for employing computational techniques for ship trim optimization. PMID:24578649

Secure and fair cluster head selection protocol for enhancing security in mobile ad hoc networks.

PubMed

Paramasivan, B; Kaliappan, M

2014-01-01

Mobile ad hoc networks (MANETs) are wireless networks consisting of number of autonomous mobile devices temporarily interconnected into a network by wireless media. MANETs become one of the most prevalent areas of research in the recent years. Resource limitations, energy efficiency, scalability, and security are the great challenging issues in MANETs. Due to its deployment nature, MANETs are more vulnerable to malicious attack. The secure routing protocols perform very basic security related functions which are not sufficient to protect the network. In this paper, a secure and fair cluster head selection protocol (SFCP) is proposed which integrates security factors into the clustering approach for achieving attacker identification and classification. Byzantine agreement based cooperative technique is used for attacker identification and classification to make the network more attack resistant. SFCP used to solve this issue by making the nodes that are totally surrounded by malicious neighbors adjust dynamically their belief and disbelief thresholds. The proposed protocol selects the secure and energy efficient cluster head which acts as a local detector without imposing overhead to the clustering performance. SFCP is simulated in network simulator 2 and compared with two protocols including AODV and CBRP.

Purdue professors review energy issues: six separate statements for the National Research Council Committee on Nuclear and Alternative Energy Systems

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

Not Available

1976-01-01

In the Introductory statement, Professor Philip N. Powers, Director of the Energy Engineering Center, discussed briefly the societal stresses resulting from energy shortfalls, the conservation and lower-growth-rate approach, the energy decision-making process, international considerations of energy supply and demand, the consideration for alternative energy sources other than nuclear or coal, and the cost-effectiveness of environmental improvements. Professor Leonard Z. Breen's statement, Energy and Society, discusses population changes, communication networks in decision making, effects of urbanizing and suburbanizing, and social impacts of changing technologies. Professor Otto C. Doering in his statement, Alternate Fuels and Agricultural Production, emphasizes such things as timemore » constraints, relative inflexibility with respect to energy source, and the biological nature of agriculture (especially weather concerns). Professor Frank P. Incropera identifies the technology of power generation (especially increasing power plant efficiency) as the first priority in his statement, Efficient Energy Utilization and Conservation. Professor Reinhardt Schuhmann, Jr. in his statement, National Problem Solving and Energy, suggests that the primary objective should be development of a new national energy process, rather than the collection and analysis of comprehensive and detailed data and rather than refinement of forecasting and scenario building. Professor Jay W. Wiley in his statement, Planning for Effective Energy Utilization, specifies certain basic understandings that must be recognized in the following areas: economic relationships, energy sources, fission nuclear energy, and electric power production in the short run. (MCW)« less

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

Lower, Mark D; Christopher, Timothy W; Oland, C Barry

The Facilities and Operations (F&O) Directorate is sponsoring a continuous process improvement (CPI) program. Its purpose is to stimulate, promote, and sustain a culture of improvement throughout all levels of the organization. The CPI program ensures that a scientific and repeatable process exists for improving the delivery of F&O products and services in support of Oak Ridge National Laboratory (ORNL) Management Systems. Strategic objectives of the CPI program include achieving excellence in laboratory operations in the areas of safety, health, and the environment. Identifying and promoting opportunities for achieving the following critical outcomes are important business goals of the CPImore » program: improved safety performance; process focused on consumer needs; modern and secure campus; flexibility to respond to changing laboratory needs; bench strength for the future; and elimination of legacy issues. The Steam Pressure-Reducing Station (SPRS) Safety and Energy Efficiency Improvement Project, which is under the CPI program, focuses on maintaining and upgrading SPRSs that are part of the ORNL steam distribution network. This steam pipe network transports steam produced at the ORNL steam plant to many buildings in the main campus site. The SPRS Safety and Energy Efficiency Improvement Project promotes excellence in laboratory operations by (1) improving personnel safety, (2) decreasing fuel consumption through improved steam system energy efficiency, and (3) achieving compliance with applicable worker health and safety requirements. The SPRS Safety and Energy Efficiency Improvement Project being performed by F&O is helping ORNL improve both energy efficiency and worker safety by modifying, maintaining, and repairing SPRSs. Since work began in 2006, numerous energy-wasting steam leaks have been eliminated, heat losses from uninsulated steam pipe surfaces have been reduced, and deficient pressure retaining components have been replaced. These improvements helped ORNL reduce its overall utility costs by decreasing the amount of fuel used to generate steam. Reduced fuel consumption also decreased air emissions. These improvements also helped lower the risk of burn injuries to workers and helped prevent shrapnel injuries resulting from missiles produced by pressurized component failures. In most cases, the economic benefit and cost effectiveness of the SPRS Safety and Energy Efficiency Improvement Project is reflected in payback periods of 1 year or less.« less

Issues with Strong Compression of Plasma Target by Stabilized Imploding Liner

NASA Astrophysics Data System (ADS)

Turchi, Peter; Frese, Sherry; Frese, Michael

2017-10-01

Strong compression (10:1 in radius) of an FRC by imploding liquid metal liners, stabilized against Rayleigh-Taylor modes, using different scalings for loss based on Bohm vs 100X classical diffusion rates, predict useful compressions with implosion times half the initial energy lifetime. The elongation (length-to-diameter ratio) near peak compression needed to satisfy empirical stability criterion and also retain alpha-particles is about ten. The present paper extends these considerations to issues of the initial FRC, including stability conditions (S*/E) and allowable angular speeds. Furthermore, efficient recovery of the implosion energy and alpha-particle work, in order to reduce the necessary nuclear gain for an economical power reactor, is seen as an important element of the stabilized liner implosion concept for fusion. We describe recent progress in design and construction of the high energy-density prototype of a Stabilized Liner Compressor (SLC) leading to repetitive laboratory experiments to develop the plasma target. Supported by ARPA-E ALPHA Program.

Ternary metal fluorides as high-energy cathodes with low cycling hysteresis

PubMed Central

Wang, Feng; Kim, Sung-Wook; Seo, Dong-Hwa; Kang, Kisuk; Wang, Liping; Su, Dong; Vajo, John J.; Wang, John; Graetz, Jason

2015-01-01

Transition metal fluorides are an appealing alternative to conventional intercalation compounds for use as cathodes in next-generation lithium batteries due to their extremely high capacity (3–4 times greater than the current state-of-the-art). However, issues related to reversibility, energy efficiency and kinetics prevent their practical application. Here we report on the synthesis, structural and electrochemical properties of ternary metal fluorides (M1yM21-yFx: M1, M2=Fe, Cu), which may overcome these issues. By substituting Cu into the Fe lattice, forming the solid–solution CuyFe1-yF2, reversible Cu and Fe redox reactions are achieved with surprisingly small hysteresis (<150 mV). This finding indicates that cation substitution may provide a new avenue for tailoring key electrochemical properties of conversion electrodes. Although the reversible capacity of Cu conversion fades rapidly, likely due to Cu+ dissolution, the low hysteresis and high energy suggest that a Cu-based fluoride cathode remains an intriguing candidate for rechargeable lithium batteries. PMID:25808876

Negative space charge effects in photon-enhanced thermionic emission solar converters

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

Segev, G.; Weisman, D.; Rosenwaks, Y.

2015-07-06

In thermionic energy converters, electrons in the gap between electrodes form a negative space charge and inhibit the emission of additional electrons, causing a significant reduction in conversion efficiency. However, in Photon Enhanced Thermionic Emission (PETE) solar energy converters, electrons that are reflected by the electric field in the gap return to the cathode with energy above the conduction band minimum. These electrons first occupy the conduction band from which they can be reemitted. This form of electron recycling makes PETE converters less susceptible to negative space charge loss. While the negative space charge effect was studied extensively in thermionicmore » converters, modeling its effect in PETE converters does not account for important issues such as this form of electron recycling, nor the cathode thermal energy balance. Here, we investigate the space charge effect in PETE solar converters accounting for electron recycling, with full coupling of the cathode and gap models, and addressing conservation of both electric and thermal energy. The analysis shows that the negative space charge loss is lower than previously reported, allowing somewhat larger gaps compared to previous predictions. For a converter with a specific gap, there is an optimal solar flux concentration. The optimal solar flux concentration, the cathode temperature, and the efficiency all increase with smaller gaps. For example, for a gap of 3 μm the maximum efficiency is 38% and the optimal flux concentration is 628, while for a gap of 5 μm the maximum efficiency is 31% and optimal flux concentration is 163.« less

Sustainable Chemistry at Sungkyunkwan University.

PubMed

Park, Nam-Gyu

2015-07-20

Special Issue: Sustainable Chemistry at Sungkyunkwan University. Sustainable chemistry is key to the development of efficient renewable energies, which will become more and more important in order to combat global warming. In this Editorial, guest editor Prof. Nam-Gyu Park describes the context of this Special Issue on top-quality research towards sustainability performed at Sungkyunkwan University (SKKU) in Korea. Scientists at SKKU work on, for example, photovoltaic solar cells to generate low-cost electricity, lithium batteries and capacitors to store electricity, piezoelectric nanogenerators, thermoelectric devices, hydrogen generation, and fuel cells. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of Magnetic Nanoparticles and External Magnetostatic Field on the Bulk Heterojunction Polymer Solar Cells

DOE PAGES

Wang, Kai; Yi, Chao; Liu, Chang; ...

2015-03-18

The price of energy to separate tightly bound electron-hole pair (or charge-transfer state) and extract freely movable charges from low-mobility materials represents fundamental losses for many low-cost photovoltaic devices. In bulk heterojunction (BHJ) polymer solar cells (PSCs), approximately 50% of the total efficiency lost among all energy loss pathways is due to the photogenerated charge carrier recombination within PSCs and low charge carrier mobility of disordered organic materials. To address these issues, we introduce magnetic nanoparticles (MNPs) and orientate these MNPS within BHJ composite by an external magnetostatic field. Over 50% enhanced efficiency was observed from BHJ PSCs incorporated withmore » MNPs and an external magnetostatic field alignment when compared to the control BHJ PSCs. The optimization of BHJ thin film morphology, suppression of charge carrier recombination, and enhancement in charge carrier collection result in a greatly increased short-circuit current density and fill factor, as a result, enhanced power conversion efficiency.« less

A System of Systems (SoS) Approach to Sustainable Energy Planning in MENA

NASA Astrophysics Data System (ADS)

Mahlooji, Maral; Ristic, Bora; Price, Katherine; Madani, Kaveh

2016-04-01

The global issue of climate change has put pressure on governments to de-carbonise their energy portfolios by transitioning from the dominant use of fossil fuels energy to extensive use of renewable energies. The lack of renewable energy laws and credible targets and valid roadmaps for energy policies within the MENA region has let to ambitious and unrealistic renewable targets, where countries such as Djibouti and Morocco are aiming for 100% and 42% renewables respectively, by 2020, while Kuwait and Qatar are only aiming for 5% and 6% respectively. Nevertheless, this demonstrates the commitment and desirability of the members of the MENA region on increasing their share of renewables in their energy mix to reduce the greenhouse gas emissions of the region and minimise the unintended impacts of energy technologies on major natural resources through use of cost efficient technologies. The Relative Aggregate Footprint (RAF) of energy sources among the member states of the MENA region is assessed by applying the "System of Systems (SoS) Approach to Energy Sustainability Assessment" (Hadian and Madani, 2015). RAF demonstrates the efficiency of the overall resource-use of energy resources through creating a trade-off between carbon footprint, land footprint, water footprint, and economic cost. Using the resource availability of each member states, weights are assigned to the four criteria. This allows the evaluation of the desirability of energy sources with respect to regional resource availability and therefore, the efficiency of the overall resource-use of the energy portfolio of the MENA region is determined. This study has recognised the need for reform and radical changes within the MENA region's energy profile to make a significant contribution to the reduction of carbon emissions in order to use the resources in a sustainable way and increase the regional energy security of the member states across MENA. Reference: Hadian S, Madani K (2015) A System of Systems Approach to Energy Sustainability Assessment: Are All Renewables Really Green? Ecological Indicators, 52, 194-206.

76 FR 37407 - Energy Conservation Program: Energy Conservation Standards for Residential Furnaces and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-27

...The Energy Policy and Conservation Act of 1975 (EPCA), as amended, prescribes energy conservation standards for various consumer products and certain commercial and industrial equipment, including residential furnaces and residential central air conditioners and heat pumps. EPCA also requires the U.S. Department of Energy (DOE) to determine whether more-stringent, amended standards for these products would be technologically feasible and economically justified, and would save a significant amount of energy. In this direct final rule, DOE adopts amended energy conservation standards for residential furnaces and for residential central air conditioners and heat pumps. A notice of proposed rulemaking that proposes identical energy efficiency standards is published elsewhere in this issue of the Federal Register. If DOE receives adverse comment and determines that such comment may provide a reasonable basis for withdrawing the direct final rule, this final rule will be withdrawn, and DOE will proceed with the proposed rule.

Chapter 11. Fuel Economy: The Case for Market Failure

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

Greene, David L; German, John; Delucchi, Mark A

2009-01-01

The efficiency of energy using durable goods, from automobiles to home air conditioners, is not only a key determinant of economy-wide energy use but also of greenhouse gas (GHG) emissions, climate change and energy insecurity. Energy analysts have long noted that consumers appear to have high implicit discount rates for future fuel savings when choosing among energy using durable goods (Howarth and Sanstad, 1995). In modeling consumers choices of appliances, the Energy Information Administration (EIA) has used discount rates of 30 percent for heating systems, 69 percent for choice of refrigerator and up to 111 percent for choice of watermore » heater (U.S. DOE/EIA, 1996). Several explanations have been offered for this widespread phenomenon, including asymmetric information, bounded rationality and transaction costs. This chapter argues that uncertainty combined with loss aversion by consumers is sufficient to explain the failure to adopt cost effective energy efficiency improvements in the market for automotive fuel economy, although other market failures appear to be present as well. Understanding how markets for energy efficiency function is crucial to formulating effective energy policies (see Pizer, 2006). Fischer et al., (2004), for example, demonstrated that if consumers fully value the discounted present value of future fuel savings, fuel economy standards are largely redundant and produce small welfare losses. However, if consumers value only the first three years of fuel savings, then fuel economy standards can significantly increase consumer welfare. The nature of any market failure that might be present in the market for energy efficiency would also affect the relative efficacy of energy taxes versus regulatory standards (CBO, 2003). If markets function efficiently, energy taxes would generally be more efficient than regulatory standards in increasing energy efficiency and reducing energy use. If markets are decidedly inefficient, standards would likely be more effective. The chapter explores the roles of uncertainty and loss-aversion in the market for automotive fuel economy. The focus is on the determination of the technical efficiency of the vehicle rather than consumers choices among vehicles. Over the past three decades, changes in the mix of vehicles sold has played little if any role in raising the average fuel economy of new light-duty vehicles from 13 miles per gallon (mpg) in 1975 to 21 mpg today (Heavenrich, 2006). Over that same time period, average vehicle weight is up 2 percent, horsepower is up 60 percent, passenger car interior volume increased by 2 percent and the market share of light trucks grew by 31 percentage points. Historically, at least, increasing light-duty vehicle fuel economy in the United States has been a matter of manufacturers decisions to apply technology to increase the technical efficiency of cars and light trucks. Understanding how efficiently the market determines the technical fuel economy of new vehicles would seem to be critical to formulating effective policies to encourage future fuel economy improvement. The central issue is whether or not the market for fuel economy is economically efficient. Rubenstein (1998) lists the key assumptions of the rational economic decision model. The decision maker must have a clear picture of the choice problem he or she faces. He should be fully aware of the set of alternatives from which to choose and have the skill necessary to make complicated calculations needed to discover the optimal course of action. Finally, the decision maker should have the unlimited ability to calculate and be indifferent to alternatives and choice sets.« less

A probabilistic dynamic energy model for ad-hoc wireless sensors network with varying topology

NASA Astrophysics Data System (ADS)

Al-Husseini, Amal

In this dissertation we investigate the behavior of Wireless Sensor Networks (WSNs) from the degree distribution and evolution perspective. In specific, we focus on implementation of a scale-free degree distribution topology for energy efficient WSNs. WSNs is an emerging technology that finds its applications in different areas such as environment monitoring, agricultural crop monitoring, forest fire monitoring, and hazardous chemical monitoring in war zones. This technology allows us to collect data without human presence or intervention. Energy conservation/efficiency is one of the major issues in prolonging the active life WSNs. Recently, many energy aware and fault tolerant topology control algorithms have been presented, but there is dearth of research focused on energy conservation/efficiency of WSNs. Therefore, we study energy efficiency and fault-tolerance in WSNs from the degree distribution and evolution perspective. Self-organization observed in natural and biological systems has been directly linked to their degree distribution. It is widely known that scale-free distribution bestows robustness, fault-tolerance, and access efficiency to system. Fascinated by these properties, we propose two complex network theoretic self-organizing models for adaptive WSNs. In particular, we focus on adopting the Barabasi and Albert scale-free model to fit into the constraints and limitations of WSNs. We developed simulation models to conduct numerical experiments and network analysis. The main objective of studying these models is to find ways to reducing energy usage of each node and balancing the overall network energy disrupted by faulty communication among nodes. The first model constructs the wireless sensor network relative to the degree (connectivity) and remaining energy of every individual node. We observed that it results in a scale-free network structure which has good fault tolerance properties in face of random node failures. The second model considers additional constraints on the maximum degree of each node as well as the energy consumption relative to degree changes. This gives more realistic results from a dynamical network perspective. It results in balanced network-wide energy consumption. The results show that networks constructed using the proposed approach have good properties for different centrality measures. The outcomes of the presented research are beneficial to building WSN control models with greater self-organization properties which leads to optimal energy consumption.

Efficiency assessment of wastewater treatment plants: A data envelopment analysis approach integrating technical, economic, and environmental issues.

PubMed

Castellet, Lledó; Molinos-Senante, María

2016-02-01

The assessment of the efficiency of wastewater treatment plants (WWTPs) is essential to compare their performance and consequently to identify the best operational practices that can contribute to the reduction of operational costs. Previous studies have evaluated the efficiency of WWTPs using conventional data envelopment analysis (DEA) models. Most of these studies have considered the operational costs of the WWTPs as inputs, while the pollutants removed from wastewater are treated as outputs. However, they have ignored the fact that each pollutant removed by a WWTP involves a different environmental impact. To overcome this limitation, this paper evaluates for the first time the efficiency of a sample of WWTPs by applying the weighted slacks-based measure model. It is a non-radial DEA model which allows assigning weights to the inputs and outputs according their importance. Thus, the assessment carried out integrates environmental issues with the traditional "techno-economic" efficiency assessment of WWTPs. Moreover, the potential economic savings for each cost item have been quantified at a plant level. It is illustrated that the WWTPs analyzed have significant room to save staff and energy costs. Several managerial implications to help WWTPs' operators make informed decisions were drawn from the methodology and empirical application carried out. Copyright © 2015 Elsevier Ltd. All rights reserved.

Transport of phase space densities through tetrahedral meshes using discrete flow mapping

NASA Astrophysics Data System (ADS)

Bajars, Janis; Chappell, David J.; Søndergaard, Niels; Tanner, Gregor

2017-01-01

Discrete flow mapping was recently introduced as an efficient ray based method determining wave energy distributions in complex built up structures. Wave energy densities are transported along ray trajectories through polygonal mesh elements using a finite dimensional approximation of a ray transfer operator. In this way the method can be viewed as a smoothed ray tracing method defined over meshed surfaces. Many applications require the resolution of wave energy distributions in three-dimensional domains, such as in room acoustics, underwater acoustics and for electromagnetic cavity problems. In this work we extend discrete flow mapping to three-dimensional domains by propagating wave energy densities through tetrahedral meshes. The geometric simplicity of the tetrahedral mesh elements is utilised to efficiently compute the ray transfer operator using a mixture of analytic and spectrally accurate numerical integration. The important issue of how to choose a suitable basis approximation in phase space whilst maintaining a reasonable computational cost is addressed via low order local approximations on tetrahedral faces in the position coordinate and high order orthogonal polynomial expansions in momentum space.

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.

Conductive Fabric-Based Stretchable Hybridized Nanogenerator for Scavenging Biomechanical Energy.

PubMed

Zhang, Kewei; Wang, Zhong Lin; Yang, Ya

2016-04-26

We demonstrate a stretchable hybridized nanogenerator based on a highly conductive fabric of glass fibers/silver nanowires/polydimethylsiloxane. Including a triboelectric nanogenerator and an electromagnetic generator, the hybridized nanogenerator can deliver output voltage/current signals from stretchable movements by both triboelectrification and electromagnetic induction, maximizing the efficiency of energy scavenging from one motion. Compared to the individual energy-harvesting units, the hybridized nanogenerator has a better charging performance, where a 47 μF capacitor can be charged to 2.8 V in only 16 s. The hybridized nanogenerator can be integrated with a bus grip for scavenging wasted biomechanical energy from human body movements to solve the power source issue of some electric devices in the pure electric bus.

Energy-efficient privacy protection for smart home environments using behavioral semantics.

PubMed

Park, Homin; Basaran, Can; Park, Taejoon; Son, Sang Hyuk

2014-09-02

Research on smart environments saturated with ubiquitous computing devices is rapidly advancing while raising serious privacy issues. According to recent studies, privacy concerns significantly hinder widespread adoption of smart home technologies. Previous work has shown that it is possible to infer the activities of daily living within environments equipped with wireless sensors by monitoring radio fingerprints and traffic patterns. Since data encryption cannot prevent privacy invasions exploiting transmission pattern analysis and statistical inference, various methods based on fake data generation for concealing traffic patterns have been studied. In this paper, we describe an energy-efficient, light-weight, low-latency algorithm for creating dummy activities that are semantically similar to the observed phenomena. By using these cloaking activities, the amount of  fake data transmissions can be flexibly controlled to support a trade-off between energy efficiency and privacy protection. According to the experiments using real data collected from a smart home environment, our proposed method can extend the lifetime of the network by more than 2× compared to the previous methods in the literature. Furthermore, the activity cloaking method supports low latency transmission of real data while also significantly reducing the accuracy of the wireless snooping attacks.

Energy-Efficient Privacy Protection for Smart Home Environments Using Behavioral Semantics

PubMed Central

Park, Homin; Basaran, Can; Park, Taejoon; Son, Sang Hyuk

2014-01-01

Research on smart environments saturated with ubiquitous computing devices is rapidly advancing while raising serious privacy issues. According to recent studies, privacy concerns significantly hinder widespread adoption of smart home technologies. Previous work has shown that it is possible to infer the activities of daily living within environments equipped with wireless sensors by monitoring radio fingerprints and traffic patterns. Since data encryption cannot prevent privacy invasions exploiting transmission pattern analysis and statistical inference, various methods based on fake data generation for concealing traffic patterns have been studied. In this paper, we describe an energy-efficient, light-weight, low-latency algorithm for creating dummy activities that are semantically similar to the observed phenomena. By using these cloaking activities, the amount of fake data transmissions can be flexibly controlled to support a trade-off between energy efficiency and privacy protection. According to the experiments using real data collected from a smart home environment, our proposed method can extend the lifetime of the network by more than 2× compared to the previous methods in the literature. Furthermore, the activity cloaking method supports low latency transmission of real data while also significantly reducing the accuracy of the wireless snooping attacks. PMID:25184489

Design of New Power Management Circuit for Light Energy Harvesting System

PubMed Central

Jafer, Issa; Stack, Paul; MacNamee, Kevin

2016-01-01

Nowadays, it can be observed that Wireless Sensors Networks (WSN) are taking increasingly vital roles in many applications, such as building energy monitoring and control, which is the focus of the work in this paper. However, the main challenging issue with adopting WSN technology is the use of power sources such as batteries, which have a limited lifetime. A smart solution that could tackle this problem is using Energy Harvesting technology. The work in this paper will be focused on proposing a new power management design through harvesting indoor light intensity. The new approach is inspired by the use of the Fractional Open Circuit Voltage based Maximum Power Point tracking (MPPT) concept for sub mw Photo Voltaic (PV) cells. The new design adopts two main features: First, it minimizes the power consumed by the power management section; and second, it maximizes the MPPT-converted output voltage and consequently improves the efficiency of the power conversion in the sub mw power level. The new experimentally-tested design showed an improvement of 81% in the efficiency of MPPT conversion using 0.5 mW input power in comparison with the other presented solutions that showed less efficiency with higher input power. PMID:26907300

An Analysis of the Cost and Performance of Photovoltaic Systems as a Function of Module Area

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

Horowitz, Kelsey A.W.; Fu, Ran; Silverman, Tim

We investigate the potential effects of module area on the cost and performance of photovoltaic systems. Applying a bottom-up methodology, we analyzed the costs associated with mc-Si and thin-film modules and systems as a function of module area. We calculate a potential for savings of up to $0.04/W, $0.10/W, and $0.13/W in module manufacturing costs for mc-Si, CdTe, and CIGS respectively, with large area modules. We also find that an additional $0.05/W savings in balance-of-systems costs may be achieved. However, these savings are dependent on the ability to maintain efficiency and manufacturing yield as area scales. Lifetime energy yield mustmore » also be maintained to realize reductions in the levelized cost of energy. We explore the possible effects of module size on efficiency and energy production, and find that more research is required to understand these issues for each technology. Sensitivity of the $/W cost savings to module efficiency and manufacturing yield is presented. We also discuss non-cost barriers to adoption of large area modules.« less

Fundamental Study of Energy Storage for Electric Railway Combining Electric Double-layer Capacitors and Battery

NASA Astrophysics Data System (ADS)

Konishi, Takeshi; Hase, Shin-Ichi; Nakamichi, Yoshinobu; Nara, Hidetaka; Uemura, Tadashi

The methods to stabilize power sources, which are the measures against voltage drop, power loading fluctuation, regenerative power lapse and so on, have been important issues in DC railway feeding circuits. Therefore, an energy storage medium that uses power efficiently and reduces above-mentioned problems is much concerned about. Electric double-layer capacitors (EDLC) can be charged and discharged rapidly in a short time with large power. On the other hand, a battery has a high energy density so that it is proper to be charged and discharged for a long time. Therefore, from a viewpoint of load pattern for electric railway, hybrid energy storage system combining both energy storage media may be effective. This paper introduces two methods for hybrid energy system theoretically, and describes the results of the fundamental tests.

Operation and planning of coordinated natural gas and electricity infrastructures

NASA Astrophysics Data System (ADS)

Zhang, Xiaping

Natural gas is becoming rapidly the optimal choice for fueling new generating units in electric power system driven by abundant natural gas supplies and environmental regulations that are expected to cause coal-fired generation retirements. The growing reliance on natural gas as a dominant fuel for electricity generation throughout North America has brought the interaction between the natural gas and power grids into sharp focus. The primary concern and motivation of this research is to address the emerging interdependency issues faced by the electric power and natural gas industry. This thesis provides a comprehensive analysis of the interactions between the two systems regarding the short-term operation and long-term infrastructure planning. Natural gas and renewable energy appear complementary in many respects regarding fuel price and availability, environmental impact, resource distribution and dispatchability. In addition, demand response has also held the promise of making a significant contribution to enhance system operations by providing incentives to customers for a more flat load profile. We investigated the coordination between natural gas-fired generation and prevailing nontraditional resources including renewable energy, demand response so as to provide economical options for optimizing the short-term scheduling with the intense natural gas delivery constraints. As the amount and dispatch of gas-fired generation increases, the long-term interdependency issue is whether there is adequate pipeline capacity to provide sufficient gas to natural gas-fired generation during the entire planning horizon while it is widely used outside the power sector. This thesis developed a co-optimization planning model by incorporating the natural gas transportation system into the multi-year resource and transmission system planning problem. This consideration would provide a more comprehensive decision for the investment and accurate assessment for system adequacy and reliability. With the growing reliance on natural gas and widespread utilization of highly efficient combined heat and power (CHP), it is also questionable that whether the independent design of infrastructures can meet potential challenges of future energy supply. To address this issue, this thesis proposed an optimization framework for a sustainable multiple energy system expansion planning based on an energy hub model while considering the energy efficiency, emission and reliability performance. In addition, we introduced the probabilistic reliability evaluation and flow network analysis into the multiple energy system design in order to obtain an optimal and reliable network topology.

Building America Best Practices Series Volume 12: Builders Challenge Guide to 40% Whole-House Energy Savings in the Cold and Very Cold Climates

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

Baechler, Michael C.; Gilbride, Theresa L.; Hefty, Marye G.

2011-02-01

This best practices guide is the twelfth in a series of guides for builders produced by PNNL for the U.S. Department of Energy’s Building America program. This guide book is a resource to help builders design and construct homes that are among the most energy-efficient available, while addressing issues such as building durability, indoor air quality, and occupant health, safety, and comfort. With the measures described in this guide, builders in the cold and very cold climates can build homes that have whole-house energy savings of 40% over the Building America benchmark with no added overall costs for consumers. Themore » best practices described in this document are based on the results of research and demonstration projects conducted by Building America’s research teams. Building America brings together the nation’s leading building scientists with over 300 production builders to develop, test, and apply innovative, energy-efficient construction practices. Building America builders have found they can build homes that meet these aggressive energy-efficiency goals at no net increased costs to the homeowners. Currently, Building America homes achieve energy savings of 40% greater than the Building America benchmark home (a home built to mid-1990s building practices roughly equivalent to the 1993 Model Energy Code). The recommendations in this document meet or exceed the requirements of the 2009 IECC and 2009 IRC and thos erequirements are highlighted in the text. This document will be distributed via the DOE Building America website: www.buildingamerica.gov.« less

Rechargeable Al-CO2 Batteries for Reversible Utilization of CO2.

PubMed

Ma, Wenqing; Liu, Xizheng; Li, Chao; Yin, Huiming; Xi, Wei; Liu, Ruirui; He, Guang; Zhao, Xian; Luo, Jun; Ding, Yi

2018-05-21

The excessive emission of CO 2 and the energy crisis are two major issues facing humanity. Thus, the electrochemical reduction of CO 2 and its utilization in metal-CO 2 batteries have attracted wide attention because the batteries can simultaneously accelerate CO 2 fixation/utilization and energy storage/release. Here, rechargeable Al-CO 2 batteries are proposed and realized, which use chemically stable Al as the anode. The batteries display small discharge/charge voltage gaps down to 0.091 V and high energy efficiencies up to 87.7%, indicating an efficient battery performance. Their chemical reaction mechanism to produce the performance is revealed to be 4Al + 9CO 2 ↔ 2Al 2 (CO 3 ) 3 + 3C, by which CO 2 is reversibly utilized. These batteries are envisaged to effectively and safely serve as a potential CO 2 fixation/utilization strategy with stable Al. © 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Representing energy efficiency diagnosis strategies in cognitive work analysis.

PubMed

Hilliard, Antony; Jamieson, Greg A

2017-03-01

This article describes challenges encountered in applying Jens Rasmussen's Cognitive Work Analysis (CWA) framework to the practice of energy efficiency Monitoring & Targeting (M&T). Eight theoretic issues encountered in the analysis are described with respect to Rasmussen's work and the modeling solutions we adopted. We grappled with how to usefully apply Work Domain Analysis (WDA) to analyze categories of domains with secondary purposes and no ideal grain of decomposition. This difficulty encouraged us to pursue Control Task (ConTA) and Strategies (StrA) analysis, which are under-explored as bases for interface design. In ConTA we found M&T was best represented by two interlinked work functions; one controlling energy, the other maintaining knowledge representations. From StrA, we identified a popular representation-dependent strategy and inferred information required to diagnose faults in system performance and knowledge representation. This article presents and discusses excerpts from our analysis, and outlines their application to diagnosis support tools. Copyright © 2015 Elsevier Ltd. All rights reserved.

MQ-MAC: A Multi-Constrained QoS-Aware Duty Cycle MAC for Heterogeneous Traffic in Wireless Sensor Networks

PubMed Central

Monowar, Muhammad Mostafa; Rahman, Md. Obaidur; Hong, Choong Seon; Lee, Sungwon

2010-01-01

Energy conservation is one of the striking research issues now-a-days for power constrained wireless sensor networks (WSNs) and hence, several duty-cycle based MAC protocols have been devised for WSNs in the last few years. However, assimilation of diverse applications with different QoS requirements (i.e., delay and reliability) within the same network also necessitates in devising a generic duty-cycle based MAC protocol that can achieve both the delay and reliability guarantee, termed as multi-constrained QoS, while preserving the energy efficiency. To address this, in this paper, we propose a Multi-constrained QoS-aware duty-cycle MAC for heterogeneous traffic in WSNs (MQ-MAC). MQ-MAC classifies the traffic based on their multi-constrained QoS demands. Through extensive simulation using ns-2 we evaluate the performance of MQ-MAC. MQ-MAC provides the desired delay and reliability guarantee according to the nature of the traffic classes as well as achieves energy efficiency. PMID:22163439

Understanding the human dimensions of a sustainable energy transition.

PubMed

Steg, Linda; Perlaviciute, Goda; van der Werff, Ellen

2015-01-01

Global climate change threatens the health, economic prospects, and basic food and water sources of people. A wide range of changes in household energy behavior is needed to realize a sustainable energy transition. We propose a general framework to understand and encourage sustainable energy behaviors, comprising four key issues. First, we need to identify which behaviors need to be changed. A sustainable energy transition involves changes in a wide range of energy behaviors, including the adoption of sustainable energy sources and energy-efficient technology, investments in energy efficiency measures in buildings, and changes in direct and indirect energy use behavior. Second, we need to understand which factors underlie these different types of sustainable energy behaviors. We discuss three main factors that influence sustainable energy behaviors: knowledge, motivations, and contextual factors. Third, we need to test the effects of interventions aimed to promote sustainable energy behaviors. Interventions can be aimed at changing the actual costs and benefits of behavior, or at changing people's perceptions and evaluations of different costs and benefits of behavioral options. Fourth, it is important to understand which factors affect the acceptability of energy policies and energy systems changes. We discuss important findings from psychological studies on these four topics, and propose a research agenda to further explore these topics. We emphasize the need of an integrated approach in studying the human dimensions of a sustainable energy transition that increases our understanding of which general factors affect a wide range of energy behaviors as well as the acceptability of different energy policies and energy system changes.

Understanding the human dimensions of a sustainable energy transition

PubMed Central

Steg, Linda; Perlaviciute, Goda; van der Werff, Ellen

2015-01-01

Global climate change threatens the health, economic prospects, and basic food and water sources of people. A wide range of changes in household energy behavior is needed to realize a sustainable energy transition. We propose a general framework to understand and encourage sustainable energy behaviors, comprising four key issues. First, we need to identify which behaviors need to be changed. A sustainable energy transition involves changes in a wide range of energy behaviors, including the adoption of sustainable energy sources and energy-efficient technology, investments in energy efficiency measures in buildings, and changes in direct and indirect energy use behavior. Second, we need to understand which factors underlie these different types of sustainable energy behaviors. We discuss three main factors that influence sustainable energy behaviors: knowledge, motivations, and contextual factors. Third, we need to test the effects of interventions aimed to promote sustainable energy behaviors. Interventions can be aimed at changing the actual costs and benefits of behavior, or at changing people’s perceptions and evaluations of different costs and benefits of behavioral options. Fourth, it is important to understand which factors affect the acceptability of energy policies and energy systems changes. We discuss important findings from psychological studies on these four topics, and propose a research agenda to further explore these topics. We emphasize the need of an integrated approach in studying the human dimensions of a sustainable energy transition that increases our understanding of which general factors affect a wide range of energy behaviors as well as the acceptability of different energy policies and energy system changes. PMID:26136705

Feasibility survey on international cooperation for high efficiency energy conversion technology in fiscal 1993

NASA Astrophysics Data System (ADS)

1994-03-01

Following cooperative researches on fuel cell jointly conducted by NEDO and EGAT (Electricity Generating Authority of Thailand), the survey on international cooperation relating to high efficiency energy conversion technology was carried out for the ASEAN countries. The paper summed up the results of the survey. The study of the international cooperation is made for the following three items: a program for periodical exchange of information with EGAT, a project for cooperative research on phosphoric acid fuel cell in Indonesia, and a project for cooperative research with EGAT on electric power storage by advanced battery. In Malaysia, which is small in scale of state, part of the Ministry of Energy, Telecommunication and Posts is only in charge of the energy issue. Therefore, the situation is that they cannot answer well to many items of research/development cooperation brought in from Japan. The item of medium- and long-term developmental research in the Philippines is about the problems which are seen subsequently in the Manila metropolitan area where the problem of outage is being settled. Accordingly, it is essential to promote the cooperative research, well confirming policies and systems of the Ministry of Energy and the national electricity corporation.

Evaluating knowledge benefits of automotive lightweighting materials R&D projects.

PubMed

Peretz, Jean H; Das, Sujit; Tonn, Bruce E

2009-08-01

This paper presents a set of metrics used to evaluate short-run knowledge benefits that accrued from research and development (R&D) projects funded in fiscal years 2000-2004 by automotive lightweighting materials (ALM) of the U.S. Department of Energy (DOE). Although DOE presents to Congress energy, environmental, and security benefits and costs of its R&D efforts under the Government Performance and Results Act, DOE has yet to include knowledge benefits in that report [U.S. Department of Energy. (2007). Projected benefits of federal energy efficiency and renewable energy programs: FY2008 budget request. NREL/TP-640-41347 (March). Washington, DC: National Renewable Energy Laboratory for DOE Energy Efficiency and Renewable Energy. Retrieved February 12, 2007 from http://www1.eere.energy.gov/ba/pba/2008_benefits.html]. ALM focuses on development and validation of advanced technologies that significantly reduce automotive vehicle body and chassis weight without compromising other attributes such as safety, performance, recyclability, and cost [U.S. Department of Energy. (2005a). Automotive lightweighting materials 2004 annual progress report. Washington, DC: DOE Energy Efficiency and Renewable Energy. Retrieved March 30, 2005 from http://www.eere.energy.gov/vehiclesandfuels/resources/fcvt_alm_fy04.shtml]. The ultimate goal of ALM to have lightweighter materials in vehicles hinges on many issues, including the (1) collaborative nature of ALMs R&D with the automobile industry and (2) manufacturing knowledge gained through the R&D effort. The ALM projects evaluated in this paper yielded numerous knowledge benefits in the short run. While these knowledge benefits are impressive, there remains uncertainty about whether the research will lead to incorporation of lightweight materials by the Big Three automakers into their manufacturing process and introduction of lightweight vehicles into the marketplace. The uncertainty illustrates a difference between (1) knowledge benefits and (2) energy, environmental, and security benefits emanating from R&D.

Functional unit, technological dynamics, and scaling properties for the life cycle energy of residences.

PubMed

Frijia, Stephane; Guhathakurta, Subhrajit; Williams, Eric

2012-02-07

Prior LCA studies take the operational phase to include all energy use within a residence, implying a functional unit of all household activities, but then exclude related supply chains such as production of food, appliances, and household chemicals. We argue that bounding the functional unit to provision of a climate controlled space better focuses the LCA on the building, rather than activities that occur within a building. The second issue explored in this article is how technological change in the operational phase affects life cycle energy. Heating and cooling equipment is replaced at least several times over the lifetime of a residence; improved efficiency of newer equipment affects life cycle energy use. The third objective is to construct parametric models to describe LCA results for a family of related products. We explore these three issues through a case study of energy use of residences: one-story and two-story detached homes, 1,500-3,500 square feet in area, located in Phoenix, Arizona, built in 2002 and retired in 2051. With a restricted functional unit and accounting for technological progress, approximately 30% of a building's life cycle energy can be attributed to materials and construction, compared to 0.4-11% in previous studies.

Optimizing the Energy and Throughput of a Water-Quality Monitoring System.

PubMed

Olatinwo, Segun O; Joubert, Trudi-H

2018-04-13

This work presents a new approach to the maximization of energy and throughput in a wireless sensor network (WSN), with the intention of applying the approach to water-quality monitoring. Water-quality monitoring using WSN technology has become an interesting research area. Energy scarcity is a critical issue that plagues the widespread deployment of WSN systems. Different power supplies, harvesting energy from sustainable sources, have been explored. However, when energy-efficient models are not put in place, energy harvesting based WSN systems may experience an unstable energy supply, resulting in an interruption in communication, and low system throughput. To alleviate these problems, this paper presents the joint maximization of the energy harvested by sensor nodes and their information-transmission rate using a sum-throughput technique. A wireless information and power transfer (WIPT) method is considered by harvesting energy from dedicated radio frequency sources. Due to the doubly near-far condition that confronts WIPT systems, a new WIPT system is proposed to improve the fairness of resource utilization in the network. Numerical simulation results are presented to validate the mathematical formulations for the optimization problem, which maximize the energy harvested and the overall throughput rate. Defining the performance metrics of achievable throughput and fairness in resource sharing, the proposed WIPT system outperforms an existing state-of-the-art WIPT system, with the comparison based on numerical simulations of both systems. The improved energy efficiency of the proposed WIPT system contributes to addressing the problem of energy scarcity.

Optimizing the Energy and Throughput of a Water-Quality Monitoring System

PubMed Central

Olatinwo, Segun O.

2018-01-01

This work presents a new approach to the maximization of energy and throughput in a wireless sensor network (WSN), with the intention of applying the approach to water-quality monitoring. Water-quality monitoring using WSN technology has become an interesting research area. Energy scarcity is a critical issue that plagues the widespread deployment of WSN systems. Different power supplies, harvesting energy from sustainable sources, have been explored. However, when energy-efficient models are not put in place, energy harvesting based WSN systems may experience an unstable energy supply, resulting in an interruption in communication, and low system throughput. To alleviate these problems, this paper presents the joint maximization of the energy harvested by sensor nodes and their information-transmission rate using a sum-throughput technique. A wireless information and power transfer (WIPT) method is considered by harvesting energy from dedicated radio frequency sources. Due to the doubly near–far condition that confronts WIPT systems, a new WIPT system is proposed to improve the fairness of resource utilization in the network. Numerical simulation results are presented to validate the mathematical formulations for the optimization problem, which maximize the energy harvested and the overall throughput rate. Defining the performance metrics of achievable throughput and fairness in resource sharing, the proposed WIPT system outperforms an existing state-of-the-art WIPT system, with the comparison based on numerical simulations of both systems. The improved energy efficiency of the proposed WIPT system contributes to addressing the problem of energy scarcity. PMID:29652866

Macroporous Double-Network Hydrogel for High-Efficiency Solar Steam Generation Under 1 sun Illumination.

PubMed

Yin, Xiangyu; Zhang, Yue; Guo, Qiuquan; Cai, Xiaobing; Xiao, Junfeng; Ding, Zhifeng; Yang, Jun

2018-04-04

Solar steam generation is one of the most promising solar-energy-harvesting technologies to address the issue of water shortage. Despite intensive efforts to develop high-efficiency solar steam generation devices, challenges remain in terms of the relatively low solar thermal efficiency, complicated fabrications, high cost, and difficulty in scaling up. Herein, a double-network hydrogel with a porous structure (p-PEGDA-PANi) is demonstrated for the first time as a flexible, recyclable, and efficient photothermal platform for low-cost and scalable solar steam generation. As a novel photothermal platform, the p-PEGDA-PANi involves all necessary properties of efficient broadband solar absorption, exceptional hydrophilicity, low heat conductivity, and porous structure for high-efficiency solar steam generation. As a result, the hydrogel-based solar steam generator exhibits a maximum solar thermal efficiency of 91.5% with an evaporation rate of 1.40 kg m -2 h -1 under 1 sun illumination, which is comparable to state-of-the-art solar steam generation devices. Furthermore, the good durability and environmental stability of the p-PEGDA-PANi hydrogel enables a convenient recycling and reusing process toward real-life applications. The present research not only provides a novel photothermal platform for solar energy harvest but also opens a new avenue for the application of the hydrogel materials in solar steam generation.

IoT-based smart garbage system for efficient food waste management.

PubMed

Hong, Insung; Park, Sunghoi; Lee, Beomseok; Lee, Jaekeun; Jeong, Daebeom; Park, Sehyun

2014-01-01

Owing to a paradigm shift toward Internet of Things (IoT), researches into IoT services have been conducted in a wide range of fields. As a major application field of IoT, waste management has become one such issue. The absence of efficient waste management has caused serious environmental problems and cost issues. Therefore, in this paper, an IoT-based smart garbage system (SGS) is proposed to reduce the amount of food waste. In an SGS, battery-based smart garbage bins (SGBs) exchange information with each other using wireless mesh networks, and a router and server collect and analyze the information for service provisioning. Furthermore, the SGS includes various IoT techniques considering user convenience and increases the battery lifetime through two types of energy-efficient operations of the SGBs: stand-alone operation and cooperation-based operation. The proposed SGS had been operated as a pilot project in Gangnam district, Seoul, Republic of Korea, for a one-year period. The experiment showed that the average amount of food waste could be reduced by 33%.

IoT-Based Smart Garbage System for Efficient Food Waste Management

PubMed Central

Lee, Jaekeun

2014-01-01

Owing to a paradigm shift toward Internet of Things (IoT), researches into IoT services have been conducted in a wide range of fields. As a major application field of IoT, waste management has become one such issue. The absence of efficient waste management has caused serious environmental problems and cost issues. Therefore, in this paper, an IoT-based smart garbage system (SGS) is proposed to reduce the amount of food waste. In an SGS, battery-based smart garbage bins (SGBs) exchange information with each other using wireless mesh networks, and a router and server collect and analyze the information for service provisioning. Furthermore, the SGS includes various IoT techniques considering user convenience and increases the battery lifetime through two types of energy-efficient operations of the SGBs: stand-alone operation and cooperation-based operation. The proposed SGS had been operated as a pilot project in Gangnam district, Seoul, Republic of Korea, for a one-year period. The experiment showed that the average amount of food waste could be reduced by 33%. PMID:25258730

Accounting Methodology for Source Energy of Non-Combustible Renewable Electricity Generation

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

Donohoo-Vallett, Paul

As non-combustible sources of renewable power (wind, solar, hydro, and geothermal) do not consume fuel, the “source” (or “primary”) energy from these sources cannot be accounted for in the same manner as it is for fossil fuel sources. The methodology chosen for these technologies is important as it affects the perception of the relative size of renewable source energy to fossil energy, affects estimates of source-based building energy use, and overall source energy based metrics such as energy productivity. This memo reviews the methodological choices, outlines implications of each choice, summarizes responses to a request for information on this topic,more » and presents guiding principles for the U.S. Department of Energy, (DOE) Office of Energy Efficiency and Renewable Energy (EERE) to use to determine where modifying the current renewable source energy accounting method used in EERE products and analyses would be appropriate to address the issues raised above.« less

World Energy Resources and New Technologies

NASA Astrophysics Data System (ADS)

Szmyd, Janusz S.

2016-01-01

The development of civilisation is linked inextricably with growing demand for electricity. Thus, the still-rapid increase in the level of utilisation of natural resources, including fossil fuels, leaves it more and more urgent that conventional energy technologies and the potential of the renewable energy sources be made subject to re-evaluation. It is estimated that last 200 years have seen use made of more than 50% of the available natural resources. Equally, if economic forecasts prove accurate, for at least several more decades, oil, natural gas and coal will go on being the basic primary energy sources. The alternative solution represented by nuclear energy remains a cause of considerable public concern, while the potential for use to be made of renewable energy sources is seen to be very much dependent on local environmental conditions. For this reason, it is necessary to emphasise the impact of research that focuses on the further sharpening-up of energy efficiency, as well as actions aimed at increasing society's awareness of the relevant issues. The history of recent centuries has shown that rapid economic and social transformation followed on from the industrial and technological revolutions, which is to say revolutions made possible by the development of power-supply technologies. While the 19th century was "the age of steam" or of coal, and the 20th century the era of oil and gas, the question now concerns the name that will at some point come to be associated with the 21st century. In this paper, the subjects of discussion are primary energy consumption and energy resources, though three international projects on the global scale are also presented, i.e. ITER, Hydrates and DESERTEC. These projects demonstrate new scientific and technical possibilities, though it is unlikely that commercialisation would prove feasible before 2050. Research should thus be focused on raising energy efficiency. The development of high-efficiency technologies that reinforce energy security is presented, with it being assumed that these new high-efficiency technologies are capable of being applied globally in the near future.

Evaluation of Signal Regeneration Impact on the Power Efficiency of Long-Haul DWDM Systems

NASA Astrophysics Data System (ADS)

Pavlovs, D.; Bobrovs, V.; Parfjonovs, M.; Alsevska, A.; Ivanovs, G.

2017-10-01

Due to potential economic benefits and expected environmental impact, the power consumption issue in wired networks has become a major challenge. Furthermore, continuously increasing global Internet traffic demands high spectral efficiency values. As a result, the relationship between spectral efficiency and energy consumption of telecommunication networks has become a popular topic of academic research over the past years, where a critical parameter is power efficiency. The present research contains calculation results that can be used by optical network designers and operators as guidance for developing more power efficient communication networks if the planned system falls within the scope of this paper. The research results are presented as average aggregated traffic curves that provide more flexible data for the systems with different spectrum availability. Further investigations could be needed in order to evaluate the parameters under consideration taking into account particular spectral parameters, e.g., the entire C-band.

The Nasal Geometry of the Reindeer Gives Energy-Efficient Respiration

NASA Astrophysics Data System (ADS)

Magnanelli, Elisa; Wilhelmsen, Øivind; Acquarone, Mario; Folkow, Lars P.; Kjelstrup, Signe

2017-01-01

Reindeer in the arctic region live under very harsh conditions and may face temperatures below 233 K. Therefore, efficient conservation of body heat and water is important for their survival. Alongside their insulating fur, the reindeer nasal mechanism for heat and mass exchange during respiration plays a fundamental role. We present a dynamic model to describe the heat and mass transport that takes place inside the reindeer nose, where we account for the complicated geometrical structure of the subsystems that are part of the nose. The model correctly captures the trend in experimental data for the temperature, heat and water recovery in the reindeer nose during respiration. As a reference case, we model a nose with a simple cylindrical-like geometry, where the total volume and contact area are the same as those determined in the reindeer nose. A comparison of the reindeer nose with the reference case shows that the nose geometry has a large influence on the velocity, temperature and water content of the air inside the nose. For all investigated cases, we find that the total entropy production during a breathing cycle is lower for the reindeer nose than for the reference case. The same trend is observed for the total energy consumption. The reduction in the total entropy production caused by the complicated geometry is higher (up to -20 %) at more extreme ambient conditions, when energy efficiency is presumably more important for the maintenance of energy balance in the animal. In the literature, a hypothesis has been proposed, which states that the most energy-efficient design of a system is characterized by equipartition of the entropy production. In agreement with this hypothesis, we find that the local entropy production during a breathing cycle is significantly more uniform for the reindeer nose than for the reference case. This suggests that natural selection has favored designs that give uniform entropy production when energy efficiency is an issue. Animals living in the harsh arctic climate, such as the reindeer, can therefore serve as inspiration for a novel industrial design with increased efficiency.

Three Essays on Macroeconomics

NASA Astrophysics Data System (ADS)

Doda, Lider Baran

This dissertation consists of three independent essays in macroeconomics. The first essay studies the transition to a low carbon economy using an extension of the neoclassical growth model featuring endogenous energy efficiency, exhaustible energy and explicit climate-economy interaction. I derive the properties of the laissez faire equilibrium and compare them to the optimal allocations of a social planner who internalizes the climate change externality. Three main results emerge. First, the exhaustibility of energy generates strong market based incentives to improve energy efficiency and reduce CO 2 emissions without any government intervention. Second, the market and optimal allocations are substantially different suggesting a role for the government. Third, high and persistent taxes are required to implement the optimal allocations as a competitive equilibrium with taxes. The second essay focuses on coal fired power plants (CFPP) - one of the largest sources of CO2 emissions globally - and their generation efficiency using a macroeconomic model with an embedded CFPP sector. A key feature of the model is the endogenous choice of production technologies which differ in their energy efficiency. After establishing four empirical facts about the CFPP sector, I analyze the long run quantitative effects of energy taxes. Using the calibrated model, I find that sector-specific coal taxes have large effects on generation efficiency by inducing the use of more efficient technologies. Moreover, such taxes achieve large CO2 emissions reductions with relatively small effects on consumption and output. The final essay studies the procyclicality of fiscal policy in developing countries, which is a well-documented empirical observation seemingly at odds with Neoclassical and Keynesian policy prescriptions. I examine this issue by solving the optimal fiscal policy problem of a small open economy government when the interest rates on external debt are endogenous. Given an incomplete asset market, endogeneity is achieved by removing the government's ability to commit to repaying its external obligations. When calibrated to Argentina, the model generates procyclical government spending and countercyclical labor income tax rates. Simultaneously, the model's implications for key business cycle moments align well with the data.

Real-Time QoS Routing Protocols in Wireless Multimedia Sensor Networks: Study and Analysis.

PubMed

Alanazi, Adwan; Elleithy, Khaled

2015-09-02

Many routing protocols have been proposed for wireless sensor networks. These routing protocols are almost always based on energy efficiency. However, recent advances in complementary metal-oxide semiconductor (CMOS) cameras and small microphones have led to the development of Wireless Multimedia Sensor Networks (WMSN) as a class of wireless sensor networks which pose additional challenges. The transmission of imaging and video data needs routing protocols with both energy efficiency and Quality of Service (QoS) characteristics in order to guarantee the efficient use of the sensor nodes and effective access to the collected data. Also, with integration of real time applications in Wireless Senor Networks (WSNs), the use of QoS routing protocols is not only becoming a significant topic, but is also gaining the attention of researchers. In designing an efficient QoS routing protocol, the reliability and guarantee of end-to-end delay are critical events while conserving energy. Thus, considerable research has been focused on designing energy efficient and robust QoS routing protocols. In this paper, we present a state of the art research work based on real-time QoS routing protocols for WMSNs that have already been proposed. This paper categorizes the real-time QoS routing protocols into probabilistic and deterministic protocols. In addition, both categories are classified into soft and hard real time protocols by highlighting the QoS issues including the limitations and features of each protocol. Furthermore, we have compared the performance of mobility-aware query based real-time QoS routing protocols from each category using Network Simulator-2 (NS2). This paper also focuses on the design challenges and future research directions as well as highlights the characteristics of each QoS routing protocol.

Real-Time QoS Routing Protocols in Wireless Multimedia Sensor Networks: Study and Analysis

PubMed Central

Alanazi, Adwan; Elleithy, Khaled

2015-01-01

Many routing protocols have been proposed for wireless sensor networks. These routing protocols are almost always based on energy efficiency. However, recent advances in complementary metal-oxide semiconductor (CMOS) cameras and small microphones have led to the development of Wireless Multimedia Sensor Networks (WMSN) as a class of wireless sensor networks which pose additional challenges. The transmission of imaging and video data needs routing protocols with both energy efficiency and Quality of Service (QoS) characteristics in order to guarantee the efficient use of the sensor nodes and effective access to the collected data. Also, with integration of real time applications in Wireless Senor Networks (WSNs), the use of QoS routing protocols is not only becoming a significant topic, but is also gaining the attention of researchers. In designing an efficient QoS routing protocol, the reliability and guarantee of end-to-end delay are critical events while conserving energy. Thus, considerable research has been focused on designing energy efficient and robust QoS routing protocols. In this paper, we present a state of the art research work based on real-time QoS routing protocols for WMSNs that have already been proposed. This paper categorizes the real-time QoS routing protocols into probabilistic and deterministic protocols. In addition, both categories are classified into soft and hard real time protocols by highlighting the QoS issues including the limitations and features of each protocol. Furthermore, we have compared the performance of mobility-aware query based real-time QoS routing protocols from each category using Network Simulator-2 (NS2). This paper also focuses on the design challenges and future research directions as well as highlights the characteristics of each QoS routing protocol. PMID:26364639

Inlet Diameter and Flow Volume Effects on Separation and Energy Efficiency of Hydrocyclones

NASA Astrophysics Data System (ADS)

Erikli, Ş.; Olcay, A. B.

2015-08-01

This study investigates hydrocyclone performance of an oil injected screw compressor. Especially, the oil separation efficiency of a screw compressor plays a significant role for air quality and non-stop working hour of compressors has become an important issue when the efficiency in energy is considered. In this study, two separation efficiency parameters were selected to be hydrocyclone inlet diameter and flow volume height between oil reservoir surface and top of the hydrocyclone. Nine different cases were studied in which cyclone inlet diameter and flow volume height between oil reservoir surface and top were investigated in regards to separation and energy performance aspects and the effect of the parameters on the general performance appears to be causing powerful influence. Flow inside the hydrocyclone geometry was modelled by Reynolds Stress Model (RSM) and hydro particles were tracked by Discrete Phase Model (DPM). Besides, particle break up was modelled by the Taylor Analogy Breakup (TAB) model. The reversed vortex generation was observed at different planes. The upper limit of the inlet diameter of the cyclone yields the centrifugal force on particles to decrease while the flow becomes slower; and the larger diameter implies slower flow. On the contrary, the lower limit is increment in speed causes breakup problems that the particle diameters become smaller; consequently, it is harder to separate them from gas.

The role of ion-exchange membrane in energy conversion

NASA Astrophysics Data System (ADS)

Khoiruddin, Aryanti, Putu T. P.; Hakim, Ahmad N.; Wenten, I. Gede

2017-05-01

Ion-exchange membrane (IEM) may play an important role in the future of electrical energy generation which is considered as renewable and clean energy. Fell cell (FC) is one of the promising technologies for solving energy issues in the future owing to the interesting features such as high electrical efficiency, low emissions, low noise level, and modularity. IEM-based processes, such as microbial fuel cell (MFC) and reverse electrodialysis (RED) may be combined with water or wastewater treatment into an integrated system. By using the integrated system, water and energy could be produced simultaneously. The IEM-based processes can be used for direct electricity generation or long term energy storage such as by harnessing surplus electricity from an existing renewable energy system to be converted into hydrogen gas via electrolysis or stored into chemical energy via redox flow battery (RFB). In this paper, recent development and applications of IEM-based processes in energy conversion are reviewed. In addition, perspective and challenges of IEM-based processes in energy conversion are pointed out.

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.

Building America Best Practices Series Volume 13: Energy Performance Techniques and Technologies: Preserving Historic Homes

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

Britt, Michelle L.; Baechler, Michael C.; Gilbride, Theresa L.

2011-03-01

This guide is a resource to help contractors renovate historic houses, while addressing issues such as building durability, indoor air quality, and occupant health, safety, and comfort. The best practices described in this document are based on the results of research and demonstration projects conducted by Building America’s research teams. Building America brings together the nation’s leading building scientists with over 300 production builders to develop, test, and apply innovative, energy-efficient construction practices. The guide is available for download from the DOE Building America website www.buildingamerica.gov.

Energy-efficient Public Procurement: Best Practice in Program Delivery

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

Payne, Christopher; Weber, Andrew; Semple, Abby

2013-02-15

This document illustrates the key issues and considerations involved in implementing energy-efficient public procurement. Our primary sources of information have been our partners in the Super Efficient Equipment and Appliance Deployment (SEAD) Initiative Procurement Working Group. Where applicable, we have highlighted specific ways in which working group participants have successfully overcome barriers to delivering effective programs. The following key points emerge from this analysis of programs for energy-efficient public procurement. Lessons for both developed and developing programs are highlighted throughout the guide. 1. Policy: Policy provides the initiative to begin a transition from first cost to life-cycle cost based purchasingmore » methods and culture. Effective policy is well-communicated, establishes accountability from top to bottom of organizations and simplifies the processes necessary to comply. Flexibility and responsiveness are essential in policy development and implementation. Mandatory and voluntary policies may complement one another. 2. Procurement Criteria: Procurement staff must be confident that energy-efficient procurement criteria offer the best long-term value for their organization’s money and represent real environmental gains. Involving multiple stakeholders at the early stages of the criteria creation process can result in greater levels of cooperation from private industry. Criteria should make comparison of products easy for purchasers and require minimal additional calculations. Criteria will need to be regularly updated to reflect market developments. 3. Training: Resources for the creation of training programs are usually very limited, but well-targeted training is necessary in order for a program to be effective. Training must emphasize a process that is efficient for purchasers and simplifies compliance. Purchaser resources and policy must be well designed for training to be effective. Training program development is an excellent opportunity for collaboration amongst public authorities. 4. Procurement Processes: Many tools and guides intended to help buyers comply with energy-efficient procurement policy are designed without detailed knowledge of the procurement process. A deeper understanding of purchasing pathways allows resources to be better directed. Current research by national and international bodies aims to analyze purchasing pathways and can assist in developing future resources.« less

Energy-efficient growth of phage Q Beta in Escherichia coli.

PubMed

Kim, Hwijin; Yin, John

2004-10-20

The role of natural selection in the optimal design of organisms is controversial. Optimal forms, functions, or behaviors of organisms have long been claimed without knowledge of how genotype contributes to phenotype, delineation of design constraints, or reference to alternative designs. Moreover, arguments for optimal designs have been often based on models that were difficult, if not impossible, to test. Here, we begin to address these issues by developing and probing a kinetic model for the intracellular growth of bacteriophage Q beta in Escherichia coli. The model accounts for the energetic costs of all template-dependent polymerization reactions, in ATP equivalents, including RNA-dependent RNA elongation by the phage replicase and synthesis of all phage proteins by the translation machinery of the E. coli host cell. We found that translation dominated phage growth, requiring 85% of the total energy expenditure. Only 10% of the total energy was applied to activities other than the direct synthesis of progeny phage components, reflecting primarily the cost of making the negative-strand RNA template that is needed for replication of phage genomic RNA. Further, we defined an energy efficiency of phage growth and showed its direct relationship to the yield of phage progeny. Finally, we performed a sensitivity analysis and found that the growth of wild-type phage was optimized for progeny yield or energy efficiency, suggesting that phage Q beta has evolved to optimally utilize the finite resources of its host cells.

Integration of Energy Consumption and CO2 Emissions into the DES Tool with Lean Thinking

NASA Astrophysics Data System (ADS)

Nujoom, Reda; Wang, Qian

2018-01-01

Products are often made by accomplishing a number of manufacturing processes on a sequential flow line which is also known as manufacturing systems. In a traditional way, design or evaluation of a manufacturing system involves a determination or an analysis of the system performance by adjusting system parameters relating to such as system capacity, material processing time, material-handling and transportation and shop-floor layout. Environment related parameters, however, are not considered or considered as separate issues. In the past decade, there has been a growing concern about the environmental protection and governments almost in all over the world enforced certain rules and regulation to promote energy saving and reduce carbon dioxide (CO2) emissions in manufacturing industry. To date, development of a sustainable manufacturing system requires designers who need not merely to apply traditional methods of improving system efficiency and productivity but also examine the environmental issues in production of the developed manufacturing system. Most researchers, however, focused on operational systems, which do not incorporate the effect of environmental factors that may also affect the system performance. This paper presents a research work aiming to addresses these issues in design and evaluation of sustainable manufacturing systems incorporating parameters of energy consumption and CO2 emissions into a DES (discrete event simulation) tool.

Simulated Tempering Distributed Replica Sampling, Virtual Replica Exchange, and Other Generalized-Ensemble Methods for Conformational Sampling.

PubMed

Rauscher, Sarah; Neale, Chris; Pomès, Régis

2009-10-13

Generalized-ensemble algorithms in temperature space have become popular tools to enhance conformational sampling in biomolecular simulations. A random walk in temperature leads to a corresponding random walk in potential energy, which can be used to cross over energetic barriers and overcome the problem of quasi-nonergodicity. In this paper, we introduce two novel methods: simulated tempering distributed replica sampling (STDR) and virtual replica exchange (VREX). These methods are designed to address the practical issues inherent in the replica exchange (RE), simulated tempering (ST), and serial replica exchange (SREM) algorithms. RE requires a large, dedicated, and homogeneous cluster of CPUs to function efficiently when applied to complex systems. ST and SREM both have the drawback of requiring extensive initial simulations, possibly adaptive, for the calculation of weight factors or potential energy distribution functions. STDR and VREX alleviate the need for lengthy initial simulations, and for synchronization and extensive communication between replicas. Both methods are therefore suitable for distributed or heterogeneous computing platforms. We perform an objective comparison of all five algorithms in terms of both implementation issues and sampling efficiency. We use disordered peptides in explicit water as test systems, for a total simulation time of over 42 μs. Efficiency is defined in terms of both structural convergence and temperature diffusion, and we show that these definitions of efficiency are in fact correlated. Importantly, we find that ST-based methods exhibit faster temperature diffusion and correspondingly faster convergence of structural properties compared to RE-based methods. Within the RE-based methods, VREX is superior to both SREM and RE. On the basis of our observations, we conclude that ST is ideal for simple systems, while STDR is well-suited for complex systems.

Conservation: Toward firmer ground

NASA Technical Reports Server (NTRS)

1975-01-01

The following aspects of energy conservation were discussed: conservation history and goals, conservation modes, conservation accounting-criteria, and a method to overcome obstacles. The conservation modes tested fall into one of the following categories: reduced energy consumption, increased efficiency of energy utilization, or substitution of one or more forms of energy for another which is in shorter supply or in some sense thought to be of more value. The conservation accounting criteria include net energy reduction, economic, and technical criteria. A method to overcome obstacles includes (approaches such as: direct personal impact (life style, income, security, aspiration), an element of crisis, large scale involvement of environmental, safety, and health issues, connections to big government, big business, big politics, involvement of known and speculative science and technology, appeal to moral and ethical standards, the transient nature of opportunities to correct the system.

Audit Report "The Department of Energy's Loan Guarantee Program for Innovative Energy Technologies"

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

None

2009-02-01

The Energy Policy Act of 2005 authorized the Department of Energy to guarantee loans for new or significantly improved energy production technologies that avoid, reduce, or sequester air pollutants and other greenhouse gases. As of December 2008, Congress authorized the Department to make $42.5 billion in loan guarantees to support innovative energy projects. These guarantees were authorized for up to 80% of the total project costs and were designed to promote the commercial use of innovative technologies. Under the terms of the Act, the loan guarantees are contingent upon reasonable prospect of repayment by the borrower. Consistent with the Energymore » Policy Act, the Department is responsible for soliciting and evaluating loan applications, approving loan guarantees, and monitoring project and loan guarantee performance. through December 2008, the Department had issued five solicitations for projects that support innovative clean coal technologies, energy efficiency, renewable energy, advanced electricity transmission and distribution, and nuclear and fossil energy projects. These solicitations were issued in three phases with the first in August 2006, and the final in September 2008. Eleven substantially complete applications requesting approximately $8.2 billion in loan guarantees had been received by the Department in response to the first solicitation. The Department had begun the review of applications and was in the process of completing due diligence procedures necessary to evaluate projects received in response to the first solicitation. Under current plans, the Department is to issue its first loan guarantees in the spring of 2009. Because of the importance of this program as part of an effort to address the Nation's most challenging and pressing energy needs; and, the potential risk of loss to the United States taxpayers should default occur, we initiated this review to evaluate the Department's progress in establishing internal and operational controls over its Loan Guarantee Program.« less

What limits photosynthetic energy conversion efficiency in nature? Lessons from the oceans.

PubMed

Falkowski, Paul G; Lin, Hanzhi; Gorbunov, Maxim Y

2017-09-26

Constraining photosynthetic energy conversion efficiency in nature is challenging. In principle, two yield measurements must be made simultaneously: photochemistry, fluorescence and/or thermal dissipation. We constructed two different, extremely sensitive and precise active fluorometers: one measures the quantum yield of photochemistry from changes in variable fluorescence, the other measures fluorescence lifetimes in the picosecond time domain. By deploying the pair of instruments on eight transoceanic cruises over six years, we obtained over 200 000 measurements of fluorescence yields and lifetimes from surface waters in five ocean basins. Our results revealed that the average quantum yield of photochemistry was approximately 0.35 while the average quantum yield of fluorescence was approximately 0.07. Thus, closure on the energy budget suggests that, on average, approximately 58% of the photons absorbed by phytoplankton in the world oceans are dissipated as heat. This extraordinary inefficiency is associated with the paucity of nutrients in the upper ocean, especially dissolved inorganic nitrogen and iron. Our results strongly suggest that, in nature, most of the time, most of the phytoplankton community operates at approximately half of its maximal photosynthetic energy conversion efficiency because nutrients limit the synthesis or function of essential components in the photosynthetic apparatus.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'. © 2017 The Author(s).

Renewable Energy and Climate Change

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

Chum, H. L.

2012-01-01

The Intergovernmental Panel on Climate Change issued the Special Report on Renewable Energy Sources and Climate Change Mitigation (SRREN) at http://srren.ipcc-wg3.de/ (May 2011 electronic version; printed form ISBN 978-1-107-60710-1, 2012). More than 130 scientists contributed to the report.* The SRREN assessed existing literature on the future potential of renewable energy for the mitigation of climate change within a portfolio of mitigation options including energy conservation and efficiency, fossil fuel switching, RE, nuclear and carbon capture and storage (CCS). It covers the six most important renewable energy technologies - bioenergy, direct solar, geothermal, hydropower, ocean and wind, as well as theirmore » integration into present and future energy systems. It also takes into consideration the environmental and social consequences associated with these technologies, the cost and strategies to overcome technical as well as non-technical obstacles to their application and diffusion.« less

Towards greener and more sustainable batteries for electrical energy storage

NASA Astrophysics Data System (ADS)

Larcher, D.; Tarascon, J.-M.

2015-01-01

Ever-growing energy needs and depleting fossil-fuel resources demand the pursuit of sustainable energy alternatives, including both renewable energy sources and sustainable storage technologies. It is therefore essential to incorporate material abundance, eco-efficient synthetic processes and life-cycle analysis into the design of new electrochemical storage systems. At present, a few existing technologies address these issues, but in each case, fundamental and technological hurdles remain to be overcome. Here we provide an overview of the current state of energy storage from a sustainability perspective. We introduce the notion of sustainability through discussion of the energy and environmental costs of state-of-the-art lithium-ion batteries, considering elemental abundance, toxicity, synthetic methods and scalability. With the same themes in mind, we also highlight current and future electrochemical storage systems beyond lithium-ion batteries. The complexity and importance of recycling battery materials is also discussed.

Poverty of power: energy and the economic crisis

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

Commoner, B.

1976-01-01

Economic and energy decisions based on thermodynamically sound principles can resolve many of our energy problems and bring capitalism back into balance. The Second Law of Thermodynamics, if used to compare amounts of energy available with the amounts needed, leads to the conclusion that a solar economy is needed. The use of coal as a transition fuel is preferred to the use of synthetic or nuclear fuels. Solar energy can be matched thermodynamically to end uses, has unlimited possibilities for expansion, and cannot be monopolized. The results of poor planning in the areas of transportation and production (especially of chemicalsmore » and fuels) can be reversed if energy decisions are based on efficiency rather than economics. Three articles based on this book appeared in February, 1976 issues of The New Yorker and were abstracted in EAPA 2(5), Abstract Nos. 721, 722, and 723. (DCK)« less

Design, Specification and Construction of Specialized Measurement System in the Experimental Building

NASA Astrophysics Data System (ADS)

Fedorczak-Cisak, Malgorzata; Kwasnowski, Pawel; Furtak, Marcin; Hayduk, Grzegorz

2017-10-01

Experimental buildings for “in situ” research are a very important tool for collecting data on energy efficiency of the energy-saving technologies. One of the most advanced building of this type in Poland is the Maloposkie Laboratory of Energy-saving Buildings at Cracow University of Technology. The building itself is used by scientists as a research object and research tool to test energy-saving technologies. It is equipped with a specialized measuring system consisting of approx. 3 000 different sensors distributed in technical installations and structural elements of the building (walls, ceilings, cornices) and the ground. The authors of the paper will present the innovative design and technology of this specialized instrumentation. They will discuss issues arising during the implementation and use of the building.

Optimization of urban wastewater treatment plants process with low C/N ratio

NASA Astrophysics Data System (ADS)

Zheng, L.; Xu, G. M.; Chen, J.; Chen, B.; Lv, Z.; Yang, Y. A.

2016-08-01

In southern China, the inflow of water to wastewater treatment plants has a lower concentration of organic matter. This causes treatment plants to face issues in the denitrification and phosphorus removal processes such as deficient carbon sources, high energy consumption, and unstable nitrogen removal. To resolve these issues, we propose the reconstruction of the internal reflux port, improvement of the internal reflux ratio to 200%, the addition of carbon source to anoxic zone, and the addition of phosphorus removal agents in secondary settling tank. The results of study show significantly improved efficiency of nitrogen and phosphorus removal, which ensures the stability of subsequent supply of reused water.

Review on Microwave-Matter Interaction Fundamentals and Efficient Microwave-Associated Heating Strategies

PubMed Central

Sun, Jing; Wang, Wenlong; Yue, Qinyan

2016-01-01

Microwave heating is rapidly emerging as an effective and efficient tool in various technological and scientific fields. A comprehensive understanding of the fundamentals of microwave–matter interactions is the precondition for better utilization of microwave technology. However, microwave heating is usually only known as dielectric heating, and the contribution of the magnetic field component of microwaves is often ignored, which, in fact, contributes greatly to microwave heating of some aqueous electrolyte solutions, magnetic dielectric materials and certain conductive powder materials, etc. This paper focuses on this point and presents a careful review of microwave heating mechanisms in a comprehensive manner. Moreover, in addition to the acknowledged conventional microwave heating mechanisms, the special interaction mechanisms between microwave and metal-based materials are attracting increasing interest for a variety of metallurgical, plasma and discharge applications, and therefore are reviewed particularly regarding the aspects of the reflection, heating and discharge effects. Finally, several distinct strategies to improve microwave energy utilization efficiencies are proposed and discussed with the aim of tackling the energy-efficiency-related issues arising from the application of microwave heating. This work can present a strategic guideline for the developed understanding and utilization of the microwave heating technology. PMID:28773355

Energy Conservation Projects to Benefit the Railroad Industry

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

Clifford Mirman; Promod Vohra

The Energy Conservation Projects to benefit the railroad industry using the Norfolk Southern Company as a model for the railroad industry has five unique tasks which are in areas of importance within the rail industry, and specifically in the area of energy conservation. The NIU Engineering and Technology research team looked at five significant areas in which research and development work can provide unique solutions to the railroad industry in energy the conservation. (1) Alternate Fuels - An examination of various blends of bio-based diesel fuels for the railroad industry, using Norfolk Southern as a model for the industry. Themore » team determined that bio-diesel fuel is a suitable alternative to using straight diesel fuel, however, the cost and availability across the country varies to a great extent. (2) Utilization of fuel cells for locomotive power systems - While the application of the fuel cell has been successfully demonstrated in the passenger car, this is a very advanced topic for the railroad industry. There are many safety and power issues that the research team examined. (3) Thermal and emission reduction for current large scale diesel engines - The current locomotive system generates large amount of heat through engine cooling and heat dissipation when the traction motors are used to decelerate the train. The research team evaluated thermal management systems to efficiently deal with large thermal loads developed by the operating engines. (4) Use of Composite and Exotic Replacement Materials - Research team redesigned various components using new materials, coatings, and processes to provide the needed protection. Through design, analysis, and testing, new parts that can withstand the hostile environments were developed. (5) Tribology Applications - Identification of tribology issues in the Railroad industry which play a significant role in the improvement of energy usage. Research team analyzed and developed solutions which resulted in friction modification to improve energy efficiency.« less

Economics, energy, and environmental assessment of diversified crop rotations in sub-Himalayas of India.

PubMed

Singh, Raman Jeet; Meena, Roshan Lal; Sharma, N K; Kumar, Suresh; Kumar, Kuldeep; Kumar, Dileep

2016-02-01

Reducing the carbon footprint and increasing energy use efficiency of crop rotations are the two most important sustainability issues of the modern agriculture. Present study was undertaken to assess economics, energy, and environmental parameters of common diversified crop rotations (maize-tomato, and maize-toria-wheat) vis-a-vis traditional crop rotations like maize-wheat, maize + ginger and rice-wheat of the north-western Himalayan region of India. Results revealed that maize-tomato and maize + ginger crop rotations being on par with each other produced significantly higher system productivity in terms of maize equivalent yield (30.2-36.2 t/ha) than other crop rotations (5.04-7.68 t/ha). But interestingly in terms of energy efficiencies, traditional maize-wheat system (energy efficiency 7.9, human energy profitability of 177.8 and energy profitability of 6.9 MJ/ha) was significantly superior over other systems. Maize + ginger rotation showed greater competitive advantage over other rotations because of less consumption of non-renewable energy resources. Similarly, maize-tomato rotation had ability of the production process to exploit natural resources due to 14-38% less use of commercial or purchased energy sources over other crop rotations. Vegetable-based crop rotations (maize + ginger and maize-tomato) maintained significantly the least carbon footprint (0.008 and 0.019 kg CO2 eq./kg grain, respectively) and the highest profitability (154,322 and 274,161 Rs./ha net return, respectively) over other crop rotations. As the greatest inputs of energy and carbon across the five crop rotations were nitrogen fertilizer (15-29% and 17-28%, respectively), diesel (14-24% and 8-19%, respectively) and irrigation (10-27% and 11-44%, respectively), therefore, alternative sources like organic farming, conservation agriculture practices, soil and water conservation measures, rain water harvesting etc. should be encouraged to reduce dependency of direct energy and external carbon inputs particularly in sub-Himalayas of India.

Design of a tubular skylight system

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

Chao, B.L.

1996-10-01

Since its introduction to the US market in 1991, tubular skylight provides a solution to the problem of lighting up dark corners in a house. Over the years, design of similar products has emphasized on quantity alone and attention to a range of other equally important issues: efficient collecting system, selection of higher specular reflectance material, seals, distribution and quality of light, was not noted. In this paper, the fundamental design concept of an efficient tubular skylight and the possibility of collimating diffuse light is reviewed. The importance of specular reflectance of the tube material on the performance of tubularmore » skylight is demonstrated. Visual appearance (quality) of transmitted light down the tube is related in part to the yellowness index of various materials. Discussion of adequacy of current building and energy code requirements on tubular skylights is briefly touched on and energy simulation results based on a numerical code are presented.« less

Gardening as vector of a humanization of high-rise building

NASA Astrophysics Data System (ADS)

Lekareva, Nina; Zaslavskaya, Anna

2018-03-01

Article is devoted to issue of integration of vertical gardening into structure of high-rise building in the conditions of the constrained town-planning situation. On the basis of the analysis of the existing experience of design and building of "biopositive" high-rise building ecological, town-planning, social and constructive advantages of the organization of gardens on roofs and vertical gardens are considered [1]. As the main mechanism of increase in investment appeal of high-rise building the principle of a humanization due to gardening of high-rise building taking into account requirements of ecology, energy efficiency of buildings and improvement of quality of construction with minimization of expenses and maximizing comfort moves forward. The National Standards of Green construction designed to adapt the international requirements of architecture and construction of the energy efficient, eco-friendly and comfortable building or a complex to local conditions are considered [2,3].

A multi-dimensional nonlinearly implicit, electromagnetic Vlasov-Darwin particle-in-cell (PIC) algorithm

NASA Astrophysics Data System (ADS)

Chen, Guangye; Chacón, Luis; CoCoMans Team

2014-10-01

For decades, the Vlasov-Darwin model has been recognized to be attractive for PIC simulations (to avoid radiative noise issues) in non-radiative electromagnetic regimes. However, the Darwin model results in elliptic field equations that renders explicit time integration unconditionally unstable. Improving on linearly implicit schemes, fully implicit PIC algorithms for both electrostatic and electromagnetic regimes, with exact discrete energy and charge conservation properties, have been recently developed in 1D. This study builds on these recent algorithms to develop an implicit, orbit-averaged, time-space-centered finite difference scheme for the particle-field equations in multiple dimensions. The algorithm conserves energy, charge, and canonical-momentum exactly, even with grid packing. A simple fluid preconditioner allows efficient use of large timesteps, O (√{mi/me}c/veT) larger than the explicit CFL. We demonstrate the accuracy and efficiency properties of the of the algorithm with various numerical experiments in 2D3V.

Frequency stabilization and transverse mode discrimination in injection-seeded unstable resonator TEA CO2 lasers

NASA Technical Reports Server (NTRS)

Ancellet, G. M.; Menzies, R. T.; Brothers, A. M.

1987-01-01

Longitudinal mode selection by injection has been demonstrated as a viable technique for TEA-CO2 lasers with pulse energies of a Joule or greater. Once reliable generation of single-longitudinal-mode (SLM) pulses is obtained, the characteristics and the causes of intrapulse frequency variation can be studied. These include the effect of the decaying plasma, the thermal gradient due to the energy dissipation associated with the laser mechanism itself, and the pressure shift of the center frequency of the laser transition. The use of the positive-branch unstable resonator as an efficient means of coupling a discharge with large spatial dimensions to an optical cavity mode introduces another concern: namely, what can be done to emphasize transverse mode discrimination in an unstable resonator cavity while maintaining high coupling efficiency. These issues are discussed in this paper, and relevant experimental results are included.

Beyond Extreme Ultra Violet (BEUV) Radiation from Spherically symmetrical High-Z plasmas

NASA Astrophysics Data System (ADS)

Yoshida, Kensuke; Fujioka, Shinsuke; Higashiguchi, Takeshi; Ugomori, Teruyuki; Tanaka, Nozomi; Kawasaki, Masato; Suzuki, Yuhei; Suzuki, Chihiro; Tomita, Kentaro; Hirose, Ryouichi; Eshima, Takeo; Ohashi, Hayato; Nishikino, Masaharu; Scally, Enda; Nshimura, Hiroaki; Azechi, Hiroshi; O'Sullivan, Gerard

2016-03-01

Photo-lithography is a key technology for volume manufacture of high performance and compact semiconductor devices. Smaller and more complex structures can be fabricated by using shorter wavelength light in the photolithography. One of the most critical issues in development of the next generation photo-lithography is to increase energy conversion efficiency (CE) from laser to shorter wavelength light. Experimental database of beyond extreme ultraviolet (BEUV) radiation was obtained by using spherically symmetrical high-Z plasmas generated with spherically allocated laser beams. Absolute energy and spectra of BEUV light emitted from Tb, Gd, and Mo plasmas were measured with a absolutely calibrated BEUV calorimeter and a transmission grating spectrometer. 1.0 x 1012 W/cm2 is the optimal laser intensity to produced efficient BEUV light source plasmas with Tb and Gd targets. Maximum CE is achieved at 0.8% that is two times higher than the published CEs obtained with planar targets.

Efficient and accurate treatment of electron correlations with correlation matrix renormalization theory

DOE PAGES

Yao, Y. X.; Liu, J.; Liu, C.; ...

2015-08-28

We present an efficient method for calculating the electronic structure and total energy of strongly correlated electron systems. The method extends the traditional Gutzwiller approximation for one-particle operators to the evaluation of the expectation values of two particle operators in the many-electron Hamiltonian. The method is free of adjustable Coulomb parameters, and has no double counting issues in the calculation of total energy, and has the correct atomic limit. We demonstrate that the method describes well the bonding and dissociation behaviors of the hydrogen and nitrogen clusters, as well as the ammonia composed of hydrogen and nitrogen atoms. We alsomore » show that the method can satisfactorily tackle great challenging problems faced by the density functional theory recently discussed in the literature. The computational workload of our method is similar to the Hartree-Fock approach while the results are comparable to high-level quantum chemistry calculations.« less

Stakeholder analysis methodologies resource book

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

Babiuch, W.M.; Farhar, B.C.

1994-03-01

Stakeholder analysis allows analysts to identify how parties might be affected by government projects. This process involves identifying the likely impacts of a proposed action and stakeholder groups affected by that action. Additionally, the process involves assessing how these groups might be affected and suggesting measures to mitigate any adverse effects. Evidence suggests that the efficiency and effectiveness of government actions can be increased and adverse social impacts mitigated when officials understand how a proposed action might affect stakeholders. This report discusses how to conduct useful stakeholder analyses for government officials making decisions on energy-efficiency and renewable-energy technologies and theirmore » commercialization. It discusses methodological issues that may affect the validity and reliability of findings, including sampling, generalizability, validity, ``uncooperative`` stakeholder groups, using social indicators, and the effect of government regulations. The Appendix contains resource directories and a list of specialists in stakeholder analysis and involvement.« less

Increasing Efficiency by Maximizing Electrical Output

DTIC Science & Technology

2016-07-27

in a few limited areas, one being a geothermal flash plant at Naval Air Weapons Station China Lake. But, there are few other heat to electricity...generation sources (but, closest to geothermal because of the lack of combustion and the maintenance issues involved with combustion). [11] Clearly, a...of Energy Resources Technology, March 2009, Vol. 131 [4] “The Chena Hot Springs 400kW Geothermal Power Plant: Experience Gained During the First

Science You Can Use Bulletin: Burgeoning biomass: Creating efficient and sustainable forest biomass supply chains in the Rockies

Treesearch

Sue Miller; Maureen Essen; Nate Anderson; Woody Chung; Bill Elliot; Deb Page-Dumroese; Han-Sup Han; John Hogland; Christopher R. Keyes

2014-01-01

Woody biomass could be used to generate energy in the western US if the utilization process is both economically feasible and ecologically sustainable. The purpose of the RMRS-led Biomass Research and Development Initiative (BRDI) is to develop technologies, approaches, and new science that will help to make this possible. This issue of the Bulletin is focused on...

Self-Formed Hybrid Interphase Layer on Lithium Metal for High-Performance Lithium-Sulfur Batteries.

PubMed

Li, Guoxing; Huang, Qingquan; He, Xin; Gao, Yue; Wang, Daiwei; Kim, Seong H; Wang, Donghai

2018-02-27

Lithium-sulfur (Li-S) batteries are promising candidates for high-energy storage devices due to high theoretical capacities of both the sulfur cathode and lithium (Li) metal anode. Considerable efforts have been devoted to improving sulfur cathodes. However, issues associated with Li anodes, such as low Coulombic efficiency (CE) and growth of Li dendrites, remain unsolved due to unstable solid-electrolyte interphase (SEI) and lead to poor capacity retention and a short cycling life of Li-S batteries. In this work, we demonstrate a facile and effective approach to fabricate a flexible and robust hybrid SEI layer through co-deposition of aromatic-based organosulfides and inorganic Li salts using poly(sulfur-random-1,3-diisopropenylbenzene) as an additive in an electrolyte. The aromatic-based organic components with planar backbone conformation and π-π interaction in the SEI layers can improve the toughness and flexibility to promote stable and high efficient Li deposition/dissolution. The as-formed durable SEI layer can inhibit dendritic Li growth, enhance Li deposition/dissolution CE (99.1% over 420 cycles), and in turn enable Li-S batteries with good cycling stability (1000 cycles) and slow capacity decay. This work demonstrates a route to address the issues associated with Li metal anodes and promote the development of high-energy rechargeable Li metal batteries.

Building America Best Practices Series Volume 15: 40% Whole-House Energy Savings in the Hot-Humid Climate

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

Baechler, Michael C.; Gilbride, Theresa L.; Hefty, Marye G.

2011-09-01

This best practices guide is the 15th in a series of guides for builders produced by PNNL for the U.S. Department of Energy’s Building America program. This guide book is a resource to help builders design and construct homes that are among the most energy-efficient available, while addressing issues such as building durability, indoor air quality, and occupant health, safety, and comfort. With the measures described in this guide, builders in the hot-humid climate can build homes that have whole-house energy savings of 40% over the Building America benchmark with no added overall costs for consumers. The best practices describedmore » in this document are based on the results of research and demonstration projects conducted by Building America’s research teams. Building America brings together the nation’s leading building scientists with over 300 production builders to develop, test, and apply innovative, energy-efficient construction practices. Building America builders have found they can build homes that meet these aggressive energy-efficiency goals at no net increased costs to the homeowners. Currently, Building America homes achieve energy savings of 40% greater than the Building America benchmark home (a home built to mid-1990s building practices roughly equivalent to the 1993 Model Energy Code). The recommendations in this document meet or exceed the requirements of the 2009 IECC and 2009 IRC and those requirements are highlighted in the text. Requirements of the 2012 IECC and 2012 IRC are also noted in text and tables throughout the guide. This document will be distributed via the DOE Building America website: www.buildingamerica.gov.« less

Building America Best Practices Series Volume 16: 40% Whole-House Energy Savings in the Mixed-Humid Climate

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

Baechler, Michael C.; Gilbride, Theresa L.; Hefty, Marye G.

2011-09-01

This best practices guide is the 16th in a series of guides for builders produced by PNNL for the U.S. Department of Energy’s Building America program. This guide book is a resource to help builders design and construct homes that are among the most energy-efficient available, while addressing issues such as building durability, indoor air quality, and occupant health, safety, and comfort. With the measures described in this guide, builders in the mixed-humid climate can build homes that have whole-house energy savings of 40% over the Building America benchmark with no added overall costs for consumers. The best practices describedmore » in this document are based on the results of research and demonstration projects conducted by Building America’s research teams. Building America brings together the nation’s leading building scientists with over 300 production builders to develop, test, and apply innovative, energy-efficient construction practices. Building America builders have found they can build homes that meet these aggressive energy-efficiency goals at no net increased costs to the homeowners. Currently, Building America homes achieve energy savings of 40% greater than the Building America benchmark home (a home built to mid-1990s building practices roughly equivalent to the 1993 Model Energy Code). The recommendations in this document meet or exceed the requirements of the 2009 IECC and 2009 IRC and those requirements are highlighted in the text. Requirements of the 2012 IECC and 2012 IRC are also noted in text and tables throughout the guide. This document will be distributed via the DOE Building America website: www.buildingamerica.gov.« less

Exploring the Housing and Household Energy Pathways to Stress: A Mixed Methods Study.

PubMed

Hernández, Diana; Phillips, Douglas; Siegel, Eva Laura

2016-09-14

Chronic stress, known to contribute to negative physical and mental health outcomes, is closely associated with broader issues of material hardship, poor neighborhood conditions, residential instability, and inadequate housing conditions. However, few studies have comprehensively explored pathways to stress in a low-income housing environment. A mixed-methods pilot study investigated the concept of energy insecurity by looking at the impacts of weatherization and energy efficiency interventions on low-income households in the South Bronx neighborhood of New York City. In-depth interviews were conducted with 20 low-income heads of household; participants also completed health, housing and budget assessments. Physical deficiencies, economic hardship, and health issues all interacted to directly and indirectly produce living conditions that contribute to chronic stress. Households with higher stress reported more health problems. Poor quality housing led to coping responses that increased expenses, which in turn increased stress around housing and energy affordability. This study provides further support for the connections between both health and the built environment and between low socio-economic status populations and net negative health outcomes. Energy insecurity is an important contributor to chronic stress in low-income households, and isolating pathways to stress where there is potential for interventions is important for future policy and housing-based strategies.

Exploring the Housing and Household Energy Pathways to Stress: A Mixed Methods Study

PubMed Central

Hernández, Diana; Phillips, Douglas; Siegel, Eva Laura

2016-01-01

Chronic stress, known to contribute to negative physical and mental health outcomes, is closely associated with broader issues of material hardship, poor neighborhood conditions, residential instability, and inadequate housing conditions. However, few studies have comprehensively explored pathways to stress in a low-income housing environment. A mixed-methods pilot study investigated the concept of energy insecurity by looking at the impacts of weatherization and energy efficiency interventions on low-income households in the South Bronx neighborhood of New York City. In-depth interviews were conducted with 20 low-income heads of household; participants also completed health, housing and budget assessments. Physical deficiencies, economic hardship, and health issues all interacted to directly and indirectly produce living conditions that contribute to chronic stress. Households with higher stress reported more health problems. Poor quality housing led to coping responses that increased expenses, which in turn increased stress around housing and energy affordability. This study provides further support for the connections between both health and the built environment and between low socio-economic status populations and net negative health outcomes. Energy insecurity is an important contributor to chronic stress in low-income households, and isolating pathways to stress where there is potential for interventions is important for future policy and housing-based strategies. PMID:27649222

Method Evaluations for Adsorption Free Energy Calculations at the Solid/Water Interface through Metadynamics, Umbrella Sampling, and Jarzynski's Equality.

PubMed

Wei, Qichao; Zhao, Weilong; Yang, Yang; Cui, Beiliang; Xu, Zhijun; Yang, Xiaoning

2018-03-19

Considerable interest in characterizing protein/peptide-surface interactions has prompted extensive computational studies on calculations of adsorption free energy. However, in many cases, each individual study has focused on the application of free energy calculations to a specific system; therefore, it is difficult to combine the results into a general picture for choosing an appropriate strategy for the system of interest. Herein, three well-established computational algorithms are systemically compared and evaluated to compute the adsorption free energy of small molecules on two representative surfaces. The results clearly demonstrate that the characteristics of studied interfacial systems have crucial effects on the accuracy and efficiency of the adsorption free energy calculations. For the hydrophobic surface, steered molecular dynamics exhibits the highest efficiency, which appears to be a favorable method of choice for enhanced sampling simulations. However, for the charged surface, only the umbrella sampling method has the ability to accurately explore the adsorption free energy surface. The affinity of the water layer to the surface significantly affects the performance of free energy calculation methods, especially at the region close to the surface. Therefore, a general principle of how to discriminate between methodological and sampling issues based on the interfacial characteristics of the system under investigation is proposed. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mitochondrial fatty acid oxidation alterations in heart failure, ischaemic heart disease and diabetic cardiomyopathy

PubMed Central

Fillmore, N; Mori, J; Lopaschuk, G D

2014-01-01

Heart disease is a leading cause of death worldwide. In many forms of heart disease, including heart failure, ischaemic heart disease and diabetic cardiomyopathies, changes in cardiac mitochondrial energy metabolism contribute to contractile dysfunction and to a decrease in cardiac efficiency. Specific metabolic changes include a relative increase in cardiac fatty acid oxidation rates and an uncoupling of glycolysis from glucose oxidation. In heart failure, overall mitochondrial oxidative metabolism can be impaired while, in ischaemic heart disease, energy production is impaired due to a limitation of oxygen supply. In both of these conditions, residual mitochondrial fatty acid oxidation dominates over mitochondrial glucose oxidation. In diabetes, the ratio of cardiac fatty acid oxidation to glucose oxidation also increases, although primarily due to an increase in fatty acid oxidation and an inhibition of glucose oxidation. Recent evidence suggests that therapeutically regulating cardiac energy metabolism by reducing fatty acid oxidation and/or increasing glucose oxidation can improve cardiac function of the ischaemic heart, the failing heart and in diabetic cardiomyopathies. In this article, we review the cardiac mitochondrial energy metabolic changes that occur in these forms of heart disease, what role alterations in mitochondrial fatty acid oxidation have in contributing to cardiac dysfunction and the potential for targeting fatty acid oxidation to treat these forms of heart disease. LINKED ARTICLES This article is part of a themed issue on Mitochondrial Pharmacology: Energy, Injury & Beyond. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2014.171.issue-8 PMID:24147975

Ternary metal fluorides as high-energy cathodes with low cycling hysteresis

DOE PAGES

Wang, Feng; Kim, Sung -Wook; Seo, Dong -Hwa; ...

2015-03-26

In this study, transition metal fluorides are an appealing alternative to conventional intercalation compounds for use as cathodes in next-generation lithium batteries due to their extremely high capacity (3–4 times greater than the current state-of-the-art). However, issues related to reversibility, energy efficiency and kinetics prevent their practical application. Here we report on the synthesis, structural and electrochemical properties of ternary metal fluorides (M 1 yM 2 1-yF x: M 1, M 2 = Fe, Cu), which may overcome these issues. By substituting Cu into the Fe lattice, forming the solid–solution Cu yFe 1-yF 2, reversible Cu and Fe redox reactionsmore » are achieved with surprisingly small hysteresis (<150 mV). This finding indicates that cation substitution may provide a new avenue for tailoring key electrochemical properties of conversion electrodes. In conclusion, although the reversible capacity of Cu conversion fades rapidly, likely due to Cu + dissolution, the low hysteresis and high energy suggest that a Cu-based fluoride cathode remains an intriguing candidate for rechargeable lithium batteries.« less

Status of China's Energy Efficiency Standards and Labels for Appliances and International Collaboration

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

Zhou, Nan

2008-03-01

China first adopted minimum energy performance standards (MEPS) in 1989. Today, there are standards for a wide range of domestic, commercial and selected industrial equipment. In 1999, China launched a voluntary endorsement label, which has grown to cover over 40 products including water-saving products (See Figure 1). Further, in 2005, China started a mandatory energy information label (also referred to as the 'Energy Label'). Today, the Energy Label is applied to four products including: air conditioners; household refrigerators; clothes washers; and unitary air conditioners (See Figure 2). MEPS and the voluntary endorsement labeling specifications have been updated and revised inmore » order to reflect technology improvements to those products in the market. These programs have had an important impact in reducing energy consumption of appliances in China. Indeed, China has built up a strong infrastructure to develop and implement product standards. Historically, however, the government's primary focus has been on the technical requirements for efficiency performance. Less attention has been paid to monitoring and enforcement with a minimal commitment of resources and little expansion of administrative capacity in this area. Thus, market compliance with both mandatory standards and labeling programs has been questionable and actual energy savings may have been undermined as a result. The establishment of a regularized monitoring system for tracking compliance with the mandatory standard and energy information label in China is a major area for program improvement. Over the years, the Collaborative Labeling and Appliance Standards Program (CLASP) has partnered with several Chinese institutions to promote energy-efficient products in China. CLASP, together with its implementing partner Lawrence Berkeley National Laboratory (LBNL), has assisted China in developing and updating the above-mentioned standards and labeling programs. Because of the increasing need for the development of a monitoring system to track compliance with standards and labeling, CLASP, with support from Japan's Ministry of Economy, Trade and Industry (METI), has expanded its ongoing collaboration with the China National Institute of Standards (CNIS) to include enforcement and monitoring. CNIS has already begun working on the issue of compliance. CNIS has conducted modest sample testing in 2006 for refrigerators, freezers and room air-conditioners, and repeated the same task in 2007 with a similar sample size for three products (refrigerators, freezers, air-conditioners and clothes washers). And, CNIS, with technical support from LBNL, has analyzed the data collected through testing. At the same time, parallel effort has also been paid to look at the potential impact of the label to 2020. In conjunction with CNIS, CLASP technical experts reviewed the standards development timeline of the four products currently subject to the mandatory energy information label. CLASP, with the support of METI/IEEJ, collaborated with CNIS to develop the efficiency grades, providing: technical input to the process; comment and advice on particular technical issues; as well as evaluation of the results. In addition, in order to effectively evaluate the impact of the label on China's market, CLASP further provided assistance to CNIS to collect data on both the efficiency distribution and product volume distribution of refrigerators on the market. This short report summarizes the status of Standards and Labeling program, current enforcement and monitoring mechanism in China, and states the importance of international collaborations.« less

Building energy modeling for green architecture and intelligent dashboard applications

NASA Astrophysics Data System (ADS)

DeBlois, Justin

Buildings are responsible for 40% of the carbon emissions in the United States. Energy efficiency in this sector is key to reducing overall greenhouse gas emissions. This work studied the passive technique called the roof solar chimney for reducing the cooling load in homes architecturally. Three models of the chimney were created: a zonal building energy model, computational fluid dynamics model, and numerical analytic model. The study estimated the error introduced to the building energy model (BEM) through key assumptions, and then used a sensitivity analysis to examine the impact on the model outputs. The conclusion was that the error in the building energy model is small enough to use it for building simulation reliably. Further studies simulated the roof solar chimney in a whole building, integrated into one side of the roof. Comparisons were made between high and low efficiency constructions, and three ventilation strategies. The results showed that in four US climates, the roof solar chimney results in significant cooling load energy savings of up to 90%. After developing this new method for the small scale representation of a passive architecture technique in BEM, the study expanded the scope to address a fundamental issue in modeling - the implementation of the uncertainty from and improvement of occupant behavior. This is believed to be one of the weakest links in both accurate modeling and proper, energy efficient building operation. A calibrated model of the Mascaro Center for Sustainable Innovation's LEED Gold, 3,400 m2 building was created. Then algorithms were developed for integration to the building's dashboard application that show the occupant the energy savings for a variety of behaviors in real time. An approach using neural networks to act on real-time building automation system data was found to be the most accurate and efficient way to predict the current energy savings for each scenario. A stochastic study examined the impact of the representation of unpredictable occupancy patterns on model results. Combined, these studies inform modelers and researchers on frameworks for simulating holistically designed architecture and improving the interaction between models and building occupants, in residential and commercial settings. v

22.5% efficient silicon heterojunction solar cell with molybdenum oxide hole collector

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

Geissbühler, Jonas, E-mail: jonas.geissbuehler@epfl.ch; Werner, Jérémie; Martin de Nicolas, Silvia

2015-08-24

Substituting the doped amorphous silicon films at the front of silicon heterojunction solar cells with wide-bandgap transition metal oxides can mitigate parasitic light absorption losses. This was recently proven by replacing p-type amorphous silicon with molybdenum oxide films. In this article, we evidence that annealing above 130 °C—often needed for the curing of printed metal contacts—detrimentally impacts hole collection of such devices. We circumvent this issue by using electrodeposited copper front metallization and demonstrate a silicon heterojunction solar cell with molybdenum oxide hole collector, featuring a fill factor value higher than 80% and certified energy conversion efficiency of 22.5%.

A survey on investigating the need for intelligent power-aware load balanced routing protocols for handling critical links in MANETs.

PubMed

Sivakumar, B; Bhalaji, N; Sivakumar, D

2014-01-01

In mobile ad hoc networks connectivity is always an issue of concern. Due to dynamism in the behavior of mobile nodes, efficiency shall be achieved only with the assumption of good network infrastructure. Presence of critical links results in deterioration which should be detected in advance to retain the prevailing communication setup. This paper discusses a short survey on the specialized algorithms and protocols related to energy efficient load balancing for critical link detection in the recent literature. This paper also suggests a machine learning based hybrid power-aware approach for handling critical nodes via load balancing.

A Survey on Investigating the Need for Intelligent Power-Aware Load Balanced Routing Protocols for Handling Critical Links in MANETs

PubMed Central

Sivakumar, B.; Bhalaji, N.; Sivakumar, D.

2014-01-01

In mobile ad hoc networks connectivity is always an issue of concern. Due to dynamism in the behavior of mobile nodes, efficiency shall be achieved only with the assumption of good network infrastructure. Presence of critical links results in deterioration which should be detected in advance to retain the prevailing communication setup. This paper discusses a short survey on the specialized algorithms and protocols related to energy efficient load balancing for critical link detection in the recent literature. This paper also suggests a machine learning based hybrid power-aware approach for handling critical nodes via load balancing. PMID:24790546

22.5% efficient silicon heterojunction solar cell with molybdenum oxide hole collector

DOE PAGES

Geissbühler, Jonas; Werner, Jérémie; Nicolas, Silvia Martin de; ...

2015-08-24

Substituting the doped amorphous silicon films at the front of silicon heterojunction solar cells with wide-bandgap transition metal oxides can mitigate parasitic light absorption losses. This was recently proven by replacing p-type amorphous silicon with molybdenum oxide films. In this article, we evidence that annealing above 130 °C—often needed for the curing of printed metal contacts—detrimentally impacts hole collection of such devices. Furthermore, we circumvent this issue by using electrodeposited copper front metallization and demonstrate a silicon heterojunction solar cell with molybdenum oxide hole collector, featuring a fill factor value higher than 80% and certified energy conversion efficiency of 22.5%.

Beyond 11% efficient sulfide kesterite Cu 2Zn xCd 1–xSnS 4 solar cell: Effects of cadmium alloying

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

Yan, Chang; Sun, Kaiwen; Huang, Jialiang

2017-04-03

Here, kesterite Cu 2ZnSnS 4 (CZTS) thin-film solar cells have drawn worldwide attention because of outstanding performance and earth-abundant constituents. However, problems such as coexistence of complex secondary phases, the band tailing issue, short minority lifetime, bulk defects, and undesirable band alignment at p-n interfaces need to be addressed for further efficiency improvement. In this regard, Cd alloying shows promise for dealing with some of these problems. In this work, a beyond 11% efficient Cd-alloyed CZTS solar cell is achieved, and the effects of Cd-alloying and mechanism underpinning the performance improvement have been investigated. The introduction of Cd can significantlymore » reduce the band tailing issue, which is confirmed by the reduction in the difference between the photoluminescence peak and optical band gap (E g) as well as decreased Urbach energy. The microstructure, minority lifetime, and electrical properties of CZTS absorber are greatly improved by Cd alloying. Further XPS analyses show that the partial Cd alloying slightly reduces the band gap of CZTS via elevating the valence band maximum of CZTS. This suggests that there are opportunities for further efficiency improvement by engineering the absorber and the associated interface with the buffer.« less

State-of-The-Art of Modeling Methodologies and Optimization Operations in Integrated Energy System

NASA Astrophysics Data System (ADS)

Zheng, Zhan; Zhang, Yongjun

2017-08-01

Rapid advances in low carbon technologies and smart energy communities are reshaping future patterns. Uncertainty in energy productions and demand sides are paving the way towards decentralization management. Current energy infrastructures could not meet with supply and consumption challenges, along with emerging environment and economic requirements. Integrated Energy System(IES) whereby electric power, natural gas, heating couples with each other demonstrates that such a significant technique would gradually become one of main comprehensive and optimal energy solutions with high flexibility, friendly renewables absorption and improving efficiency. In these global energy trends, we summarize this literature review. Firstly the accurate definition and characteristics of IES have been presented. Energy subsystem and coupling elements modeling issues are analyzed. It is pointed out that decomposed and integrated analysis methods are the key algorithms for IES optimization operations problems, followed by exploring the IES market mechanisms. Finally several future research tendencies of IES, such as dynamic modeling, peer-to-peer trading, couple market design, sare under discussion.

Investigation on energy conversion technology using biochemical reaction elements, 2

NASA Astrophysics Data System (ADS)

1994-03-01

For measures taken for resource/energy and environmental issues, a study is made on utilization of microbial biochemical reaction. As a reaction system using chemical energy, cited is production of petroleum substitution substances and food/feed by CO2 fixation using hydrogen energy and hydrogen bacteria. As to photo energy utilization, regarded as promising are CO2 fixation using photo energy and microalgae, and production of hydrogen and useful carbon compound using photosynthetic organisms. As living organism/electric energy interconversion, cited is the culture of chemoautotrophic bacteria which fix CO2 using electric energy. For enhancing its conversion efficiency, it is important to develop a technology of gene manipulation of the bacteria and a system to use functional biochemical elements adaptable to the electrode reaction. With regard to utilization of the microorganism metabolic function, the paper presents emission of soluble nitrogen in the hydrosphere into the atmosphere using denitrifying bacteria, removal of phosphorus, reduction in environmental pollution caused by heavy metal dilute solutions, and recovery as resources, etc.

Eleven Tribes Jump START Clean Energy Projects, Summer 2012 (Newsletter)

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

Not Available

This newsletter describes key activities of the DOE Office of Indian Energy Policy and Programs for Summer 2012. The U.S. Department of Energy Office of Indian Energy Policy and Programs (DOE-IE) has selected 11 Tribes - five in Alaska and six in the contiguous United States - to receive on-the-ground technical support for community-based energy efficiency and renewable energy projects as part of DOE-IE's Strategic Technical Assistance Response Team (START) Program. START finalists were selected based on the clarity of their requests for technical assistance and the ability of START to successfully work with their projects or community. Technical expertsmore » from DOE and its National Renewable Energy Laboratory (NREL) will work directly with community-based project teams to analyze local energy issues and assist the Tribes in moving their projects forward. In Alaska, the effort will be bolstered by DOE-IE's partnership with the Denali Commission, which will provide additional assistance and expertise, as well as funding to fuel the Alaska START initiative.« less

A Review of Protocol Implementations and Energy Efficient Cross-Layer Design for Wireless Body Area Networks

PubMed Central

Hughes, Laurie; Wang, Xinheng; Chen, Tao

2012-01-01

The issues inherent in caring for an ever-increasing aged population has been the subject of endless debate and continues to be a hot topic for political discussion. The use of hospital-based facilities for the monitoring of chronic physiological conditions is expensive and ties up key healthcare professionals. The introduction of wireless sensor devices as part of a Wireless Body Area Network (WBAN) integrated within an overall eHealth solution could bring a step change in the remote management of patient healthcare. Sensor devices small enough to be placed either inside or on the human body can form a vital part of an overall health monitoring network. An effectively designed energy efficient WBAN should have a minimal impact on the mobility and lifestyle of the patient. WBAN technology can be deployed within a hospital, care home environment or in the patient's own home. This study is a review of the existing research in the area of WBAN technology and in particular protocol adaptation and energy efficient cross-layer design. The research reviews the work carried out across various layers of the protocol stack and highlights how the latest research proposes to resolve the various challenges inherent in remote continual healthcare monitoring. PMID:23202185

Increasing the doping efficiency by surface energy control for ultra-transparent graphene conductors.

PubMed

Chang, Kai-Wen; Hsieh, Ya-Ping; Ting, Chu-Chi; Su, Yen-Hsun; Hofmann, Mario

2017-08-22

Graphene's attractiveness in many applications is limited by its high resistance. Extrinsic doping has shown promise to overcome this challenge but graphene's performance remains below industry requirements. This issue is caused by a limited charge transfer efficiency (CTE) between dopant and graphene. Using AuCl 3 as a model system, we measure CTE as low as 5% of the expected values due to the geometrical capacitance of small adsorbate clusters. We here demonstrate a strategy for enhancing the CTE by a two-step optimization of graphene's surface energy prior to AuCl 3 doping. First, exposure to UV ozone modified the hydrophilicity of graphene and was found to decrease the cluster's geometric capacitance, which had a direct effect on the CTE. Occurrence of lattice defects at high UV exposure, however, deteriorated graphene's transport characteristics and limited the effectiveness of this pretreatment step. Thus, prior to UV exposure, a functionalized polymer layer was introduced that could further enhance graphene's surface energy while protecting it from damage. Combination of these treatment steps were found to increase the AuCl 3 charge transfer efficiency to 70% and lower the sheet resistance to 106 Ω/γ at 97% transmittance which represents the highest reported performance for doped single layer graphene and is on par with commercially available transparent conductors.

EDITORIAL: Special issue on green photonics Special issue on green photonics

NASA Astrophysics Data System (ADS)

Boardman, Allan; Brongersma, Mark; Polman, Albert

2012-02-01

Photovoltaic (PV) cells can provide virtually unlimited amounts of energy by effectively converting sunlight into clean electrical power. Over the years, significant research and development efforts have been devoted to improving the structural and charge transport properties of the materials used in PV cells. Despite these efforts, the current energy conversion efficiencies of commercial solar cells are still substantially lower than the ultimate limits set by thermodynamics. Economic arguments in addition to the scarcity of some semiconductors and materials used in transparent conductive oxides are also driving us to use less and less material in a cell. For these reasons, it is clear that new approaches need to be found. One possible solution that is more-or-less orthogonal to previous approaches is aimed at managing the photons rather than the electrons or atoms in a cell. This type of photon management is termed Green Photonics. Nano- and micro-photonic trapping techniques are currently gaining significant attention. The use of engineered plasmonic and high refractive index structures shows tremendous potential for enhancing the light absorption per unit volume in semiconductors. Unfortunately, the design space in terms of the nanostructure sizes, shapes, and array structures is too large to allow for optimization of PV cells using brute force simulations. For this reason, new intuitive models and rapid optimization techniques for advanced light trapping technologies need to be developed. At the same time we need to come up with new, inexpensive, and scalable nanostructure fabrication and optical characterization techniques in order to realize the dream of inexpensive, high power conversion efficiency cells that make economic sense. This special issue discusses some of the exciting new approaches to light trapping that leverage the most recent advances in the field of nanophotonics. It also provides some insights into why giving the green light to green photonics may help play a role in resolving the pending energy crisis.The papers included in this `green photonics' special issue demonstrate current global activity, involving a wide range of distinguished authors.

Rotating-Sleeve Triboelectric-Electromagnetic Hybrid Nanogenerator for High Efficiency of Harvesting Mechanical Energy.

PubMed

Cao, Ran; Zhou, Tao; Wang, Bin; Yin, Yingying; Yuan, Zuqing; Li, Congju; Wang, Zhong Lin

2017-08-22

Currently, a triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG) have been hybridized to effectively scavenge mechanical energy. However, one critical issue of the hybrid device is the limited output power due to the mismatched output impedance between the two generators. In this work, impedance matching between the TENG and EMG is achieved facilely through commercial transformers, and we put forward a highly integrated hybrid device. The rotating-sleeve triboelectric-electromagnetic hybrid nanogenerator (RSHG) is designed by simulating the structure of a common EMG, which ensures a high efficiency in transferring ambient mechanical energy into electric power. The RSHG presents an excellent performance with a short-circuit current of 1 mA and open-circuit voltage of 48 V at a rotation speed of 250 rpm. Systematic measurements demonstrate that the hybrid nanogenerator can deliver the largest output power of 13 mW at a loading resistance of 8 kΩ. Moreover, it is demonstrated that a wind-driven RSHG can light dozens of light-emitting diodes and power an electric watch. The distinctive structure and high output performance promise the practical application of this rotating-sleeve structured hybrid nanogenerator for large-scale energy conversion.

The Physics of Energy

NASA Astrophysics Data System (ADS)

Jaffe, Robert L.; Taylor, Washington

2018-01-01

Part I. Basic Energy Physics and Uses: 1. Introduction; 2. Mechanical energy; 3. Electromagnetic energy; 4. Waves and light; 5. Thermodynamics I: heat and thermal energy; 6. Heat transfer; 7. Introduction to quantum physics; 8. Thermodynamics II: entropy and temperature; 9. Energy in matter; 10. Thermal energy conversion; 11. Internal combustion engines; 12. Phase-change energy conversion; 13. Thermal power and heat extraction cycles; Part II. Energy Sources: 14. The forces of nature; 15. Quantum phenomena in energy systems; 16. An overview of nuclear power; 17. Structure, properties and decays of nuclei; 18. Nuclear energy processes: fission and fusion; 19. Nuclear fission reactors and nuclear fusion experiments; 20. Ionizing radiation; 21. Energy in the universe; 22. Solar energy: solar production and radiation; 23. Solar energy: solar radiation on Earth; 24. Solar thermal energy; 25. Photovoltaic solar cells; 26. Biological energy; 27. Ocean energy flow; 28. Wind: a highly variable resource; 29. Fluids – the basics; 30. Wind turbines; 31. Energy from moving water: hydro, wave, tidal, and marine current power; 32. Geothermal energy; 33. Fossil fuels; Part III. Energy System Issues and Externalities: 34. Energy and climate; 35. Earth's climate: past, present, and future; 36. Energy efficiency, conservation, and changing energy sources; 37. Energy storage; 38. Electricity generation and transmission.

Recent Development of Plasmonic Resonance-Based Photocatalysis and Photovoltaics for Solar Utilization.

PubMed

Fan, Wenguang; Leung, Michael K H

2016-02-02

Increasing utilization of solar energy is an effective strategy to tackle our energy and energy-related environmental issues. Both solar photocatalysis (PC) and solar photovoltaics (PV) have high potential to develop technologies of many practical applications. Substantial research efforts are devoted to enhancing visible light activation of the photoelectrocatalytic reactions by various modifications of nanostructured semiconductors. This review paper emphasizes the recent advancement in material modifications by means of the promising localized surface plasmonic resonance (LSPR) mechanisms. The principles of LSPR and its effects on the photonic efficiency of PV and PC are discussed here. Many research findings reveal the promise of Au and Ag plasmonic nanoparticles (NPs). Continual investigation for increasing the stability of the plasmonic NPs will be fruitful.

Fighting detection using interaction energy force

NASA Astrophysics Data System (ADS)

Wateosot, Chonthisa; Suvonvorn, Nikom

2017-02-01

Fighting detection is an important issue in security aimed to prevent criminal or undesirable events in public places. Many researches on computer vision techniques have studied to detect the specific event in crowded scenes. In this paper we focus on fighting detection using social-based Interaction Energy Force (IEF). The method uses low level features without object extraction and tracking. The interaction force is modeled using the magnitude and direction of optical flows. A fighting factor is developed under this model to detect fighting events using thresholding method. An energy map of interaction force is also presented to identify the corresponding events. The evaluation is performed using NUSHGA and BEHAVE datasets. The results show the efficiency with high accuracy regardless of various conditions.

Manipulating the Electronic Excited State Energies of Pyrimidine-Based Thermally Activated Delayed Fluorescence Emitters To Realize Efficient Deep-Blue Emission.

PubMed

Komatsu, Ryutaro; Ohsawa, Tatsuya; Sasabe, Hisahiro; Nakao, Kohei; Hayasaka, Yuya; Kido, Junji

2017-02-08

The development of efficient and robust deep-blue emitters is one of the key issues in organic light-emitting devices (OLEDs) for environmentally friendly, large-area displays or general lighting. As a promising technology that realizes 100% conversion from electrons to photons, thermally activated delayed fluorescence (TADF) emitters have attracted considerable attention. However, only a handful of examples of deep-blue TADF emitters have been reported to date, and the emitters generally show large efficiency roll-off at practical luminance over several hundreds to thousands of cd m -2 , most likely because of the long delayed fluorescent lifetime (τ d ). To overcome this problem, we molecularly manipulated the electronic excited state energies of pyrimidine-based TADF emitters to realize deep-blue emission and reduced τ d . We then systematically investigated the relationships among the chemical structure, properties, and device performances. The resultant novel pyrimidine emitters, called Ac-XMHPMs (X = 1, 2, and 3), contain different numbers of bulky methyl substituents at acceptor moieties, increasing the excited singlet (E S ) and triplet state (E T ) energies. Among them, Ac-3MHPM, with a high E T of 2.95 eV, exhibited a high external quantum efficiency (η ext,max ) of 18% and an η ext of 10% at 100 cd m -2 with Commission Internationale de l'Eclairage chromaticity coordinates of (0.16, 0.15). These efficiencies are among the highest values to date for deep-blue TADF OLEDs. Our molecular design strategy provides fundamental guidance to design novel deep-blue TADF emitters.

Probabilistic monitoring in intrusion detection module for energy efficiency in mobile ad hoc networks

NASA Astrophysics Data System (ADS)

De Rango, Floriano; Lupia, Andrea

2016-05-01

MANETs allow mobile nodes communicating to each other using the wireless medium. A key aspect of these kind of networks is the security, because their setup is done without an infrastructure, so external nodes could interfere in the communication. Mobile nodes could be compromised, misbehaving during the multi-hop transmission of data, or they could have a selfish behavior to save energy, which is another important constraint in MANETs. The detection of these behaviors need a framework that takes into account the latest interactions among nodes, so malicious or selfish nodes could be detected also if their behavior is changed over time. The monitoring activity increases the energy consumption, so our proposal takes into account this issue reducing the energy required by the monitoring system, keeping the effectiveness of the intrusion detection system. The results show an improvement in the saved energy, improving the detection performance too.

Metering Best Practices, A Guide to Achieving Utility Resource Efficiency, Release 2.0

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

Sullivan, Greg; Hunt, W. D.; Pugh, Ray

2011-08-31

This release is an update and expansion of the information provided in Release 1.0 of the Metering Best Practice Guide that was issued in October 2007. This release, as was the previous release, was developed under the direction of the U.S. Department of Energy's Federal Energy Management Program (FEMP). The mission of FEMP is to facilitate the Federal Government's implementation of sound cost-effective energy management and investment practices to enhance the nation's energy security and environmental stewardship. Each of these activities is directly related to achieving requirements set forth in the Energy Policy Acts of 1992 and 2005, the Energymore » Independence and Security Act (EISA) of 2007, and the goals that have been established in Executive Orders 13423 and 13514 - and also those practices that are inherent in sound management of Federal financial and personnel resources.« less

Impact of Mixed Feedstocks and Feedstock Densification on Ionic Liquid Pretreatment Efficiency

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

Jian Shi; Vicki S. Thompson; Neal A. Yancey

2013-01-01

Background: Lignocellulosic biorefineries must be able to efficiently process the regional feedstocks that are available at cost-competitive prices year round. These feedstocks typically have low energy densities and vary significantly in composition. One potential solution to these issues is blending and/or densifying the feedstocks in order to create a uniform feedstock. Results/discussion: We have mixed four feedstocks - switchgrass, lodgepole pine, corn stover, and eucalyptus - in flour and pellet form and processed them using the ionic liquid 1-ethyl-3-methylimidazolium acetate. Sugar yields from both the mixed flour and pelletized feedstocks reach 90% within 24 hours of saccharification. Conclusions: Mixed feedstocks,more » in either flour or pellet form, are efficiently processed using this pretreatment process, and demonstrate that this approach has significant potential.« less

Resonant tunneling diodes as energy-selective contacts used in hot-carrier solar cells

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

Takeda, Yasuhiko, E-mail: takeda@mosk.tytlabs.co.jp; Sugimoto, Noriaki; Ichiki, Akihisa

2015-09-28

Among the four features unique to hot-carrier solar cells (HC-SCs): (i) carrier thermalization time and (ii) carrier equilibration time in the absorber, (iii) energy-selection width and (iv) conductance of the energy-selective contacts (ESCs), requisites of (i)-(iii) for high conversion efficiency have been clarified. We have tackled the remaining issues related to (iv) in the present study. The detailed balance model of HC-SC operation has been improved to involve a finite value of the ESC conductance to find the required values, which in turn has been revealed to be feasible using resonant tunneling diodes (RTDs) consisting of semiconductor quantum dots (QDs)more » and quantum wells (QWs) by means of a formulation to calculate the conductance of the QD- and QW-RTDs derived using the rigorous solutions of the effective-mass Hamiltonians. Thus, all of the four requisites unique to HC-SCs to achieve high conversion efficiency have been elucidated, and the two requisites related to the ESCs can be fulfilled using the QD- and QW-RTDs.« less

Enhancing energy transport in conjugated polymers

NASA Astrophysics Data System (ADS)

Holmes, Russell J.

2018-05-01

The conversion of light into usable chemical energy by plants is enabled by the precise spatial arrangement of light-absorbing photosynthetic systems and associated molecular complexes (1). In organic solar cells, there is also the need to control intermolecular spacing and molecular orientation, as well as thin-film crystallinity and morphology, so as to enable efficient energy migration and photoconversion (2). In an organic solar cell, light absorption creates excitons, tightly bound electron-hole pairs that must be efficiently dissociated into their component charge carriers in order to create an electrical current. Thus, long-range exciton migration must occur from the point of photogeneration to a dissociating site. On page 897 of this issue, Jin et al. (3) report on a conjugated polymer nanofiber system that yields exciton diffusion lengths greater than 200 nm. In comparison, organic solar cells are typically constructed with materials having exciton diffusion lengths one order of magnitude smaller than this value, which limits device thickness and optical absorption. Their approach exploits a sequential synthesis method that enables measurement of this long exciton diffusion length (see the figure).

Lowering the temperature of solid oxide fuel cells.

PubMed

Wachsman, Eric D; Lee, Kang Taek

2011-11-18

Fuel cells are uniquely capable of overcoming combustion efficiency limitations (e.g., the Carnot cycle). However, the linking of fuel cells (an energy conversion device) and hydrogen (an energy carrier) has emphasized investment in proton-exchange membrane fuel cells as part of a larger hydrogen economy and thus relegated fuel cells to a future technology. In contrast, solid oxide fuel cells are capable of operating on conventional fuels (as well as hydrogen) today. The main issue for solid oxide fuel cells is high operating temperature (about 800°C) and the resulting materials and cost limitations and operating complexities (e.g., thermal cycling). Recent solid oxide fuel cells results have demonstrated extremely high power densities of about 2 watts per square centimeter at 650°C along with flexible fueling, thus enabling higher efficiency within the current fuel infrastructure. Newly developed, high-conductivity electrolytes and nanostructured electrode designs provide a path for further performance improvement at much lower temperatures, down to ~350°C, thus providing opportunity to transform the way we convert and store energy.

The photobiological production of hydrogen: potential efficiency and effectiveness as a renewable fuel.

PubMed

Prince, Roger C; Kheshgi, Haroon S

2005-01-01

Photosynthetic microorganisms can produce hydrogen when illuminated, and there has been considerable interest in developing this to a commercially viable process. Its appealing aspects include the fact that the hydrogen would come from water, and that the process might be more energetically efficient than growing, harvesting, and processing crops. We review current knowledge about photobiological hydrogen production, and identify and discuss some of the areas where scientific and technical breakthroughs are essential for commercialization. First we describe the underlying biochemistry of the process, and identify some opportunities for improving photobiological hydrogen production at the molecular level. Then we address the fundamental quantum efficiency of the various processes that have been suggested, technological issues surrounding large-scale growth of hydrogen-producing microorganisms, and the scale and efficiency on which this would have to be practiced to make a significant contribution to current energy use.

High Efficiency, Transparent, Reusable, and Active PM2.5 Filters by Hierarchical Ag Nanowire Percolation Network.

PubMed

Jeong, Seongmin; Cho, Hyunmin; Han, Seonggeun; Won, Phillip; Lee, Habeom; Hong, Sukjoon; Yeo, Junyeob; Kwon, Jinhyeong; Ko, Seung Hwan

2017-07-12

Air quality has become a major public health issue in Asia including China, Korea, and India. Particulate matters are the major concern in air quality. We present the first environmental application demonstration of Ag nanowire percolation network for a novel, electrical type transparent, reusable, and active PM2.5 air filter although the Ag nanowire percolation network has been studied as a very promising transparent conductor in optoelectronics. Compared with previous particulate matter air filter study using relatively weaker short-range intermolecular force in polar polymeric nanofiber, Ag nanowire percolation network filters use stronger long-range electrostatic force to capture PM2.5, and they are highly efficient (>99.99%), transparent, working on an active mode, low power consumption, antibacterial, and reusable after simple washing. The proposed new particulate matter filter can be applied for a highly efficient, reusable, active and energy efficient filter for wearable electronics application.

Computational issues in complex water-energy optimization problems: Time scales, parameterizations, objectives and algorithms

NASA Astrophysics Data System (ADS)

Efstratiadis, Andreas; Tsoukalas, Ioannis; Kossieris, Panayiotis; Karavokiros, George; Christofides, Antonis; Siskos, Alexandros; Mamassis, Nikos; Koutsoyiannis, Demetris

2015-04-01

Modelling of large-scale hybrid renewable energy systems (HRES) is a challenging task, for which several open computational issues exist. HRES comprise typical components of hydrosystems (reservoirs, boreholes, conveyance networks, hydropower stations, pumps, water demand nodes, etc.), which are dynamically linked with renewables (e.g., wind turbines, solar parks) and energy demand nodes. In such systems, apart from the well-known shortcomings of water resources modelling (nonlinear dynamics, unknown future inflows, large number of variables and constraints, conflicting criteria, etc.), additional complexities and uncertainties arise due to the introduction of energy components and associated fluxes. A major difficulty is the need for coupling two different temporal scales, given that in hydrosystem modeling, monthly simulation steps are typically adopted, yet for a faithful representation of the energy balance (i.e. energy production vs. demand) a much finer resolution (e.g. hourly) is required. Another drawback is the increase of control variables, constraints and objectives, due to the simultaneous modelling of the two parallel fluxes (i.e. water and energy) and their interactions. Finally, since the driving hydrometeorological processes of the integrated system are inherently uncertain, it is often essential to use synthetically generated input time series of large length, in order to assess the system performance in terms of reliability and risk, with satisfactory accuracy. To address these issues, we propose an effective and efficient modeling framework, key objectives of which are: (a) the substantial reduction of control variables, through parsimonious yet consistent parameterizations; (b) the substantial decrease of computational burden of simulation, by linearizing the combined water and energy allocation problem of each individual time step, and solve each local sub-problem through very fast linear network programming algorithms, and (c) the substantial decrease of the required number of function evaluations for detecting the optimal management policy, using an innovative, surrogate-assisted global optimization approach.

Energy management study: A proposed case of government building

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

Tahir, Mohamad Zamhari; Nawi, Mohd Nasrun Mohd; Baharum, Mohd Faizal

Align with the current needs of the sustainable and green technology in Malaysian construction industry, this research is conducted to seek and identify opportunities to better manage energy use including the process of understand when, where, and how energy is used in a building. The purpose of this research is to provide a best practice guideline as a practical tool to assist construction industry in Malaysia to improve the energy efficiency of the office building during the post-production by reviewing the current practice of the building operation and maintenance in order to optimum the usage and reduce the amount ofmore » energy input into the building. Therefore, this paper will review the concept of maintenance management, current issue in energy management, and on how the research process will be conducted. There are several process involves and focuses on technical and management techniques such as energy metering, tracing, harvesting, and auditing based on the case study that will be accomplish soon. Accordingly, a case study is appropriate to be selected as a strategic research approach in which involves an empirical investigation of a particular contemporary phenomenon within its real life context using multiple sources of evidence for the data collection process. A Government office building will be selected as an appropriate case study for this research. In the end of this research, it will recommend a strategic approach or model in a specific guideline for enabling energy-efficient operation and maintenance in the office building.« less

Energy management study: A proposed case of government building

NASA Astrophysics Data System (ADS)

Tahir, Mohamad Zamhari; Nawi, Mohd Nasrun Mohd; Baharum, Mohd Faizal

2015-05-01

Align with the current needs of the sustainable and green technology in Malaysian construction industry, this research is conducted to seek and identify opportunities to better manage energy use including the process of understand when, where, and how energy is used in a building. The purpose of this research is to provide a best practice guideline as a practical tool to assist construction industry in Malaysia to improve the energy efficiency of the office building during the post-production by reviewing the current practice of the building operation and maintenance in order to optimum the usage and reduce the amount of energy input into the building. Therefore, this paper will review the concept of maintenance management, current issue in energy management, and on how the research process will be conducted. There are several process involves and focuses on technical and management techniques such as energy metering, tracing, harvesting, and auditing based on the case study that will be accomplish soon. Accordingly, a case study is appropriate to be selected as a strategic research approach in which involves an empirical investigation of a particular contemporary phenomenon within its real life context using multiple sources of evidence for the data collection process. A Government office building will be selected as an appropriate case study for this research. In the end of this research, it will recommend a strategic approach or model in a specific guideline for enabling energy-efficient operation and maintenance in the office building.

EDITORIAL: Semiconductor nanotechnology: novel materials and devices for electronics, photonics and renewable energy applications Semiconductor nanotechnology: novel materials and devices for electronics, photonics and renewable energy applications

NASA Astrophysics Data System (ADS)

Goodnick, Stephen; Korkin, Anatoli; Krstic, Predrag; Mascher, Peter; Preston, John; Zaslavsky, Alex

2010-04-01

Electronic and photonic information technology and renewable energy alternatives, such as solar energy, fuel cells and batteries, have now reached an advanced stage in their development. Cost-effective improvements to current technological approaches have made great progress, but certain challenges remain. As feature sizes of the latest generations of electronic devices are approaching atomic dimensions, circuit speeds are now being limited by interconnect bottlenecks. This has prompted innovations such as the introduction of new materials into microelectronics manufacturing at an unprecedented rate and alternative technologies to silicon CMOS architectures. Despite the environmental impact of conventional fossil fuel consumption, the low cost of these energy sources has been a long-standing economic barrier to the development of alternative and more efficient renewable energy sources, fuel cells and batteries. In the face of mounting environmental concerns, interest in such alternative energy sources has grown. It is now widely accepted that nanotechnology offers potential solutions for securing future progress in information and energy technologies. The Canadian Semiconductor Technology Conference (CSTC) forum was established 25 years ago in Ottawa as an important symbol of the intrinsic strength of the Canadian semiconductor research and development community, and the Canadian semiconductor industry as a whole. In 2007, the 13th CSTC was held in Montreal, moving for the first time outside the national capital region. The first three meetings in the series of 'Nano and Giga Challenges in Electronics and Photonics'— NGCM2002 in Moscow, NGCM2004 in Krakow, and NGC2007 in Phoenix— were focused on interdisciplinary research from the fundamentals of materials science to the development of new system architectures. In 2009 NGC2009 and the 14th Canadian Semiconductor Technology Conference (CSTC2009) were held as a joint event, hosted by McMaster University (10-14 August, Hamilton, Ontario, Canada) and the scope was expanded to include renewable energy research and development. This special issue of Nanotechnology is devoted to a better understanding of the function and design of semiconductor devices that are relevant to information technology (both electronics and photonics based) and renewable energy applications. The papers contained in this special issue are selected from the NGC/CSTC2009 symposium. Among them is a report by Ray LaPierre from McMaster University and colleagues at the University of Waterloo in Canada on the ability to manipulate single spins in nanowire quantum bits. The paper also reports the development of a testbed of a few qubits for general quantum information processing tasks [1]. Lower cost and greater energy conversion efficiency compared with thin film devices have led to a high level of activity in nanowire research related to photovoltaic applications. This special issue also contains results from an impedance spectroscopy study of core-shell GaAs nanowires to throw light on the transport and recombination mechanisms relevant to solar cell research [2]. Information technology research and renewable energy sources are research areas of enormous public interest. This special issue addresses both theoretical and experimental achievements and provides a stimulating outlook for technological developments in these highly topical fields of research. References [1] Caram J, Sandoval C, Tirado M, Comedi D, Czaban J, Thompson D A and LaPierre R R 2101 Nanotechnology 21 134007 [2] Baugh J, Fung J S and LaPierre RR 2010 Nanotechnology 21 134018

The Department of Defense: Reducing Its Reliance on Fossil-Based Aviation Fuel - Issues for Congress

DTIC Science & Technology

2007-06-15

19 Figure 2. KC-135 Winglet Flight Tests at Dryden Flight Research Center . . . . 23 List of Tables Table 1...involving two or more opposing forces using rules, data, and procedures designed to depict an actual or assumed real life situation.” 19 Winglets , for...applying winglets to DOD aircraft. See page 24 of this report for further information. reflect the DOD’s true fuel costs, masks energy efficiency

Worldwide Emerging Environmental Issues Affecting the U.S. Military. March 2010

DTIC Science & Technology

2010-03-01

typical vibrations in the human body. Both piezoelectric and electromagnetic induction types have been tested and are claimed to be more efficient...than previous devices with vibrations that are non-periodic and occur at low frequencies. [Related item: “Energy Harvesting ” Offers Possibilities for...polarization http://www.nature.com/nnano/ journal /vaop/ncurrent/abs/nnano.2010.34.html 6.2 New Detection and Cleanup Techniques 6.2.1 New Polymer

High-Penetration Photovoltaics Standards and Codes Workshop, Denver, Colorado, May 20, 2010: Workshop Proceedings

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

Coddington, M.; Kroposki, B.; Basso, T.

Effectively interconnecting high-level penetration of photovoltaic (PV) systems requires careful technical attention to ensuring compatibility with electric power systems. Standards, codes, and implementation have been cited as major impediments to widespread use of PV within electric power systems. On May 20, 2010, in Denver, Colorado, the National Renewable Energy Laboratory, in conjunction with the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), held a workshop to examine the key technical issues and barriers associated with high PV penetration levels with an emphasis on codes and standards. This workshop included building upon results of the Highmore » Penetration of Photovoltaic (PV) Systems into the Distribution Grid workshop held in Ontario California on February 24-25, 2009, and upon the stimulating presentations of the diverse stakeholder presentations.« less

Engineering cyanobacteria for fuels and chemicals production.

PubMed

Zhou, Jie; Li, Yin

2010-03-01

The world's energy and global warming crises call for sustainable, renewable, carbon-neutral alternatives to replace fossil fuel resources. Currently, most biofuels are produced from agricultural crops and residues, which lead to concerns about food security and land shortage. Compared to the current biofuel production system, cyanobacteria, as autotrophic prokaryotes, do not require arable land and can grow to high densities by efficiently using solar energy, CO(2), water, and inorganic nutrients. Moreover, powerful genetic techniques of cyanobacteria have been developed. For these reasons, cyanobacteria, which carry out oxygenic photosynthesis, are attractive hosts for production of fuels and chemicals. Recently, several chemicals including ethanol, isobutanol and isoprene have been produced by engineered cyanobacteria directly using solar energy, CO(2), and water. Cyanobacterium is therefore a potential novel cell factory for fuels and chemicals production to address global energy security and climate change issues.

A New Lamination and doping Concepts for Enhanced Li – S Battery Performance

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

Kumta, Prashant N.; Datta, Moni K.; Velikokhatnyi, Oleg

Lithium ion batteries (LIBs) clearly dominated the area of high-energy storage systems for the past decade with significant research and development activity focused on the development of cathode and anode materials to maximize the specific energy storage, stability, and cycle life of the batteries. However, with the increasing demand in the EV industry for low cost, low weight, and high-energy storage batteries to meet the EV everywhere grand challenge, the current focus of research has shifted towards the development of lithium sulfur batteries (LSB) owing to the high theoretical specific capacity exhibited by sulfur compared to other cathode materials currentlymore » available. Li–S battery shows a theoretical capacity of 1675 mAh/g corresponding to the formation of Li2S which makes sulfur a promising electrode to replace the layered transition metal oxides (~150 mAh/g) and LiFePO4 (~170 mAh/g) hitherto deployed in present LIB systems. Moreover, the abundance of sulfur in the earth’s crust makes it a more economical and highly attractive proposition compared to currently existing cathodes. Despite advantages of sulfur, the existing Li-S battery technology display poor cyclability, low coulombic efficiency (CE) and very low cycle life due to the following issues: 1. Polysulfide (PS) dissolution; 2. Sluggish kinetics of PS to Li2S conversion; 3. High PS diffusivity in the electrolyte; 4. Insulating nature or poor conductivity of sulfur/Li2S; 5. Volumetric expansion/contraction of sulfur; 6. Shuttling of PS along with Li+. These issues result in loss of sulfur causing mechanical disintegration, surface passivation of both anode and cathode, thereby decreasing the specific capacity and columbic efficiency (CE). Present generation sulfur cathodes also show low specific storage capacity, very poor charging rates and low loading densities. Research is needed to overcome the issues impeding Li-S battery technology development.« less

The African disability scooter: efficiency testing in paediatric amputees in Malawi

PubMed Central

Beckles, Verona; McCahill, Jennifer L.; Stebbins, Julie; Mkandawire, Nyengo; Church, John C. T.; Lavy, Chris

2016-01-01

Abstract Purpose: The African Disability Scooter (ADS) was developed for lower limb amputees, to improve mobility and provide access to different terrains. The aim of this study was to test the efficiency of the ADS in Africa over different terrains. Method: Eight subjects with a mean age of 12 years participated. Energy expenditure and speed were calculated over different terrains using the ADS, a prosthetic limb, and crutches. Repeated testing was completed on different days to assess learning effect. Results: Speed was significantly faster with the ADS on a level surface compared to crutch walking. This difference was maintained when using the scooter on rough terrain. Oxygen cost was halved with the scooter on level ground compared to crutch walking. There were no significant differences in oxygen consumption or heart rate. There were significant differences in oxygen cost and speed between days using the scooter over level ground, suggesting the presence of a learning effect. Conclusions: This study demonstrates that the ADS is faster and more energy efficient than crutch walking in young individuals with amputations, and should be considered as an alternative to a prosthesis where this is not available. The presence of a learning effect suggests supervision and training is required when the scooter is first issued.Implications for RehabilitationThe African Disability Scooter:is faster than crutch walking in amputees;is more energy efficient than walking with crutches;supervised use is needed when learning to use the device;is a good alternative/adjunct for mobility. PMID:25316033

COD capture: a feasible option towards energy self-sufficient domestic wastewater treatment

PubMed Central

Wan, Junfeng; Gu, Jun; Zhao, Qian; Liu, Yu

2016-01-01

Although the activated sludge process, one of the most remarkable engineering inventions in the 20th century, has made significant contribution to wastewater reclamation in the past 100 years, its high energy consumption is posing a serious impact and challenge on the current wastewater industry worldwide and is also inevitably linked to the issue of global climate change. In this study, we argued that substantial improvement in the energy efficiency might be no longer achievable through further optimization of the activated sludge process. Instead, we should devote more effort to the development or the adoption of novel treatment configurations and emerging technologies. Of which an example is A-B process which can significantly improve the energy recovery potential at A-stage, while markedly reduces energy consumption at B-stage. Various configurations of A-B process with energy analysis are thus discussed. It appears highly possible to achieve an overall energy gain in WWTPs with A-B process as a core. PMID:27121339

Global energy demand to 2060

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

Starr, C.

The projection of global energy demand to the year 2060 is of particular interest because of its relevance to the current greenhouse concerns. The long-term growth of global energy demand in the time scale of climatic change has received relatively little attention in the public discussion of national policy alternatives. The sociological, political, and economic issues have rarely been mentioned in this context. This study emphasizes that the two major driving forces are global population growth and economic growth (gross national product per capita), as would be expected. The modest annual increases assumed in this study result in a yearmore » 2060 annual energy use of >4 times the total global current use (year 1986) if present trends continue, and >2 times with extreme efficiency improvements in energy use. Even assuming a zero per capita growth for energy and economics, the population increase by the year 2060 results in a 1.5 times increase in total annual energy use.« less

Advertising, marketing and purchase behavior for energy-related products

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

Tiedemann, K.; Nelson, D.

Energy conservation programs have relied heavily on incentives and regulatory standards to reduce residential energy consumption. However, in the changing market environment characterized by competitive pressures, alternative mechanisms such as marketing and promotions may increase substantially in importance compared to the demand-side management programs which have been the focus of most research. This paper describes the role of marketing and promotions in encouraging energy efficiency at the household level in British Columbia. The paper examines three related issues: first, the purchase process for energy-related products; second, the criteria used by customers in making purchase decisions; and third, the impact andmore » effectiveness of alternative marketing tools. A key finding is the energy-related purchases do not fall into the impulse purchase category. There are two reasons for this: first, most of these products require installation and this requires a high level of commitment on the part of the purchaser; second, many energy-related products require a significant outlay of funds and this reduces impulse buying.« less

Integration of net zero energy building with smart grid to improve regional electrification ratio towards sustainable development

NASA Astrophysics Data System (ADS)

Latief, Yusuf; Berawi, Mohammed Ali; Supriadi, Leni; Bintang Koesalamwardi, Ario; Petroceany, Jade; Herzanita, Ayu

2017-12-01

Indonesia is currently encouraging its physical, social and economy development. Physical development for economic development have to be supported by energy availability. For Indonesia, 90% of electrification ratio is still become an important task that has to be completed by the Government. However, the effort to increase electrification can become an environmental problem if it’s done with BAU scenario. The by-product of electric generation is the GHG, which increasing every year since 2006 from various sectors i.e. industry, housing, commercial, transportation, and energy. Net Zero Energy Building (NZEB) is an energy efficient building which can produce energy independently from clean and renewable sources. The energy that is generated by NZEB can be used for the building itself, and can be exported to the central grid. The integration of NZEB and Smart Grid can solve today’s issue on electrification ratio. Literature study will find benchmarks which can be applied in Indonesia along with possible obstacles in applying this technology.

Recent progress in stabilizing hybrid perovskites for solar cell applications

NASA Astrophysics Data System (ADS)

Chen, Jianqing; Cai, Xin; Yang, Donghui; Song, Dan; Wang, Jiajia; Jiang, Jinghua; Ma, Aibin; Lv, Shiquan; Hu, Michael Z.; Ni, Chaoying

2017-07-01

Hybrid inorganic-organic perovskites have quickly evolved as a promising group of materials for solar cells and optoelectronic applications mainly owing to the inexpensive materials, relatively simple and versatile fabrication and high power conversion efficiency (PCE). The certified energy conversion efficiency for perovskite solar cell (PSC) has reached above 20%, which is compatible to the current best for commercial applications. However, long-term stabilities of the materials and devices remain to be the biggest challenging issue for realistic implementation of the PSCs. This article discusses the key issues related to the stability of perovskite absorbing layer including crystal structural stability, chemical stability under moisture, oxygen, illumination and interface reaction, effects of electron-transporting materials (ETM), hole-transporting materials (HTM), contact electrodes, ion migration and preparation conditions. Towards the end, prospective strategies for improving the stability of PSCs are also briefly discussed and summarized. We focus on recent understanding of the stability of materials and devices and our perspectives about the strategies for the stability improvement.

Development of a Comprehensive Community Nitrogen Oxide Emissions Reduction Toolkit (CCNERT)

NASA Astrophysics Data System (ADS)

Sung, Yong Hoon

The main objective of this study is to research and develop a simplified tool to estimate energy use in a community and its associated effects on air pollution. This tool is intended to predict the impacts of selected energy conservation options and efficiency programs on emission reduction. It is intended to help local government and their residents understand and manage information collection and the procedures to be used. This study presents a broad overview of the community-wide energy use and NOx emissions inventory process. It also presents various simplified procedures to estimate each sector's energy use. In an effort to better understand community-wide energy use and its associated NOx emissions, the City of College Station, Texas, was selected as a case study community for this research. While one community might successfully reduce the production of NOx emissions by adopting electricity efficiency programs in its buildings, another community might be equally successful by changing the mix of fuel sources used to generate electricity, which is consumed by the community. In yet a third community low NOx automobiles may be mandated. Unfortunately, the impact and cost of one strategy over another changes over time as major sources of pollution are reduced. Therefore, this research proposes to help community planners answer these questions and to assist local communities with their NOx emission reduction plans by developing a Comprehensive Community NOx Emissions Reduction Toolkit (CCNERT). The proposed simplified tool could have a substantial impact on reducing NOx emission by providing decision-makers with a preliminary understanding about the impacts of various energy efficiency programs on emissions reductions. To help decision makers, this study has addressed these issues by providing a general framework for examining how a community's non-renewable energy use leads to NOx emissions, by quantifying each end-user's energy usage and its associated NOx emissions, and by evaluating the environmental benefits of various types of energy saving options.

Joint China-United States Report for Year 1 Insulation Materials and Systems Project Area Clean Energy Research Center Building Energy Efficiency (CERC-BEE)

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

Stovall, Therese K; Biswas, Kaushik; Song, Bo

In November of 2009, the presidents of China and the U.S. announced the establishment of the Clean Energy Research Center (CERC). This broad research effort is co-funded by both countries and involves a large number of research centers and universities in both countries. One part of this program is focused on improving the energy efficiency of buildings. One portion of the CERC-BEE was focused on building insulation systems. The research objective of this effort was to Identify and investigate candidate high performance fire resistant building insulation technologies that meet the goal of building code compliance for exterior wall applications inmore » green buildings in multiple climate zones. A Joint Work Plan was established between researchers at the China Academy of Building Research and Oak Ridge National Laboratory. Efforts in the first year under this plan focused on information gathering. The objective of this research program is to reduce building energy use in China via improved building insulation technology. In cold regions in China, residents often use inefficient heating systems to provide a minimal comfort level within inefficient buildings. In warmer regions, air conditioning has not been commonly used. As living standards rise, energy consumption in these regions will increase dramatically unless significant improvements are made in building energy performance. Previous efforts that defined the current state of the built environment in China and in the U.S. will be used in this research. In countries around the world, building improvements have typically followed the implementation of more stringent building codes. There have been several changes in building codes in both the U.S. and China within the last few years. New U.S. building codes have increased the amount of wall insulation required in new buildings. New government statements from multiple agencies in China have recently changed the requirements for buildings in terms of energy efficiency and fire safety. A related issue is the degree to which new standards are adopted and enforced. In the U.S., standards are developed using a consensus process, and local government agencies are free to implement these standards or to ignore them. For example, some U.S. states are still using 2003 versions of the building efficiency standards. There is also a great variation in the degree to which the locally adopted standards are enforced in different U.S. cities and states. With a more central process in China, these issues are different, but possible impacts of variable enforcement efficacy may also exist. Therefore, current building codes in China will be compared to the current state of building fire-safety and energy-efficiency codes in the U.S. and areas for possible improvements in both countries will be explored. In particular, the focus of the applications in China will be on green buildings. The terminology of 'green buildings' has different meanings to different audiences. The U.S. research is interested in both new, green buildings, and on retrofitting existing inefficient buildings. An initial effort will be made to clarify the scope of the pertinent wall insulation systems for these applications.« less

An Indian scenario on renewable and sustainable energy sources with emphasis on algae.

PubMed

Hemaiswarya, S; Raja, Rathinam; Carvalho, Isabel S; Ravikumar, R; Zambare, Vasudeo; Barh, Debmalya

2012-12-01

India is the fifth largest primary energy consumer and fourth largest petroleum consumer after USA, China, and Japan. Despite the global economic crisis, India's economy is expected to grow at 6 to 8 %/year. There is an extreme dependence on petroleum products with considerable risks and environmental issues. Petroleum-derived transport fuels are of limited availability and contribute to global warming, making renewable biofuel as the best alternative. The focus on biogas and biomass-based energy, such as bioethanol and biohydrogen, will enhance cost-effectiveness and provide an opportunity for the rural community. Among all energy sources, microalgae have received, so far, more attention due to their facile adaptability to grow in the photobioreactors or open ponds, high yields, and multiple applications. Microalgae can produce a substantial amount of triacylglycerols as a storage lipid under photooxidative stress or other adverse environmental conditions. In addition to renewable biofuels, they can provide different types of high-value bioproducts added to their advantages, such as higher photosynthetic efficiency, higher biomass production, and faster growth compared to any other energy crops. The viability of first-generation biofuels production is, however, questionable because of the conflict with food supply. In the future, biofuels should ideally create the environmental, economic, and social benefits to the communities and reflect energy efficiency so as to plan a road map for the industry to produce third-generation biofuels.

Experimental model of a wind energy conversion system

NASA Astrophysics Data System (ADS)

Vasar, C.; Rat, C. L.; Prostean, O.

2018-01-01

The renewable energy domain represents an important issue for the sustainable development of the mankind in the actual context of increasing demand for energy along with the increasing pollution that affect the environment. A significant quota of the clean energy is represented by the wind energy. As a consequence, the developing of wind energy conversion systems (WECS) in order to achieve high energetic performances (efficiency, stability, availability, competitive cost etc) represents a topic of permanent actuality. Testing and developing of an optimized control strategy for a WECS direct implemented on a real energetic site is quite difficult and not cost efficient. Thus a more convenient solution consists in a flexible laboratory setup which requires an experimental model of a WECS. Such approach would allow the simulation of various real conditions very similar with existing energetic sites. This paper presents a grid-connected wind turbine emulator. The wind turbine is implemented through a real-time Hardware-in-the-Loop (HIL) emulator, which will be analyzed extensively in the paper. The HIL system uses software implemented in the LabVIEW programming environment to control an ABB ACS800 electric drive. ACS800 has the task of driving an induction machine coupled to a permanent magnet synchronous generator. The power obtained from the synchronous generator is rectified, filtered and sent to the main grid through a controlled inverter. The control strategy is implemented on a NI CompactRIO (cRIO) platform.

Collaborative Emission Reduction Model Based on Multi-Objective Optimization for Greenhouse Gases and Air Pollutants.

PubMed

Meng, Qing-chun; Rong, Xiao-xia; Zhang, Yi-min; Wan, Xiao-le; Liu, Yuan-yuan; Wang, Yu-zhi

2016-01-01

CO2 emission influences not only global climate change but also international economic and political situations. Thus, reducing the emission of CO2, a major greenhouse gas, has become a major issue in China and around the world as regards preserving the environmental ecology. Energy consumption from coal, oil, and natural gas is primarily responsible for the production of greenhouse gases and air pollutants such as SO2 and NOX, which are the main air pollutants in China. In this study, a mathematical multi-objective optimization method was adopted to analyze the collaborative emission reduction of three kinds of gases on the basis of their common restraints in different ways of energy consumption to develop an economic, clean, and efficient scheme for energy distribution. The first part introduces the background research, the collaborative emission reduction for three kinds of gases, the multi-objective optimization, the main mathematical modeling, and the optimization method. The second part discusses the four mathematical tools utilized in this study, which include the Granger causality test to analyze the causality between air quality and pollutant emission, a function analysis to determine the quantitative relation between energy consumption and pollutant emission, a multi-objective optimization to set up the collaborative optimization model that considers energy consumption, and an optimality condition analysis for the multi-objective optimization model to design the optimal-pole algorithm and obtain an efficient collaborative reduction scheme. In the empirical analysis, the data of pollutant emission and final consumption of energies of Tianjin in 1996-2012 was employed to verify the effectiveness of the model and analyze the efficient solution and the corresponding dominant set. In the last part, several suggestions for collaborative reduction are recommended and the drawn conclusions are stated.

Collaborative Emission Reduction Model Based on Multi-Objective Optimization for Greenhouse Gases and Air Pollutants

PubMed Central

Zhang, Yi-min; Wan, Xiao-le; Liu, Yuan-yuan; Wang, Yu-zhi

2016-01-01

CO2 emission influences not only global climate change but also international economic and political situations. Thus, reducing the emission of CO2, a major greenhouse gas, has become a major issue in China and around the world as regards preserving the environmental ecology. Energy consumption from coal, oil, and natural gas is primarily responsible for the production of greenhouse gases and air pollutants such as SO2 and NOX, which are the main air pollutants in China. In this study, a mathematical multi-objective optimization method was adopted to analyze the collaborative emission reduction of three kinds of gases on the basis of their common restraints in different ways of energy consumption to develop an economic, clean, and efficient scheme for energy distribution. The first part introduces the background research, the collaborative emission reduction for three kinds of gases, the multi-objective optimization, the main mathematical modeling, and the optimization method. The second part discusses the four mathematical tools utilized in this study, which include the Granger causality test to analyze the causality between air quality and pollutant emission, a function analysis to determine the quantitative relation between energy consumption and pollutant emission, a multi-objective optimization to set up the collaborative optimization model that considers energy consumption, and an optimality condition analysis for the multi-objective optimization model to design the optimal-pole algorithm and obtain an efficient collaborative reduction scheme. In the empirical analysis, the data of pollutant emission and final consumption of energies of Tianjin in 1996–2012 was employed to verify the effectiveness of the model and analyze the efficient solution and the corresponding dominant set. In the last part, several suggestions for collaborative reduction are recommended and the drawn conclusions are stated. PMID:27010658

ATIC Flight Data Processing

NASA Technical Reports Server (NTRS)

Ahn, H. S.; Whitaker, Ann F. (Technical Monitor)

2001-01-01

The first flight of the Advanced Thin Ionization Calorimeter (ATIC) experiment from McMurdo, Antarctica lasted for 16 days, starting in December, 2000. The ATIC instrument consists of a fully active 320-crystal, 960-channel Bismuth Germanate (BGO) calorimeter, 202 scintillator strips in 3 hodoscopes interleaved with a graphite target, and a 4480-pixel silicon matrix charge detector. We have developed an Object Oriented data processing package based on ROOT. In this paper, we will describe the data processing scheme used in handling the accumulated 45 GB of flight data. We will also discuss trigger issues by comparing the measured energy-dependent trigger efficiency with its simulation and calibration issues by considering the time-dependence of housekeeping information, etc.

Final report on the oxidation of energetic materials in supercritical water. Final Air Force report

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

Buelow, S.J.; Allen, D.; Anderson, G.K.

1995-04-03

The objective of this project was to determine the suitability of oxidation in supercritical fluids (SCO), particularly water (SCWO), for disposal of propellants, explosives, and pyrotechnics (PEPs). The SCO studies of PEPs addressed the following issues: The efficiency of destruction of the substrate. The products of destruction contained in the effluents. Whether the process can be conducted safely on a large scale. Whether energy recovery from the process is economically practicable. The information essential for process development and equipment design was also investigated, including issues such as practical throughput of explosives through a SCWO reactor, reactor materials and corrosion, andmore » models for process design and optimization.« less

Home retrofitting for energy conservation and solar considerations

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

Not Available

1981-10-01

This manual explains both the key concepts behind our need for and our impact on energy usage, as well as a nuts-and-bolts explanation of how to improve the energy efficiency of your home. By reviewing both the concepts and practices of energy conservation, the manual presents a comprehensive picture of how home energy use is effected by the inhabitants and by the structure itself. The manual begins with an explanation of why we are looking at energy, then proceeds to explain how the heat transfer occurs between houses and humans. Next is a chapter on energy audits and how tomore » use them, followed by a comprehensive section on energy conservation actions to do now to reduce energy use. Conservation actions include low cost/no cost measures, schemes to reduce infiltration, how to increase insulation, and what to do with windows and doors, heating and heat distribution systems, and water heaters. Solar energy options are then briefly explained, as well as the all important issues of financing and tax credits. The manual concludes with a bibliography to direct the reader to more sources of information.« less

Higher energy efficient homes are associated with increased risk of doctor diagnosed asthma in a UK subpopulation.

PubMed

Sharpe, Richard A; Thornton, Christopher R; Nikolaou, Vasilis; Osborne, Nicholas J

2015-02-01

The United Kingdom (UK) has one of the highest prevalence of asthma in the world, which represents a significant economic and societal burden. Reduced ventilation resulting from increased energy efficiency measures acts as a modifier for mould contamination and risk of allergic diseases. To our knowledge no previous study has combined detailed asset management property and health data together to assess the impact of household energy efficiency (using the UK Government's Standard Assessment Procedure) on asthma outcomes in an adult population residing in social housing. Postal questionnaires were sent to 3867 social housing properties to collect demographic, health and environmental information on all occupants. Detailed property data, residency periods, indices of multiple deprivation (IMD) and household energy efficiency ratings were also investigated. Logistic regression was used to calculate odds ratios and confidence intervals while allowing for clustering of individuals coming from the same location. Eighteen percent of our target social housing population were recruited into our study. Adults had a mean age of 59 (SD±17.3) years and there was a higher percentage of female (59%) and single occupancy (58%) respondents. Housing demographic characteristics were representative of the target homes. A unit increase in household Standard Assessment Procedure (SAP) rating was associated with a 2% increased risk of current asthma, with the greatest risk in homes with SAP >71. We assessed exposure to mould and found that the presence of a mouldy/musty odour was associated with a two-fold increased risk of asthma (OR 2.2 95%; CI 1.3-3.8). A unit increase in SAP led to a 4-5% reduction in the risk of visible mould growth and a mouldy/musty odour. In contrast to previous research, we report that residing in energy efficient homes may increase the risk of adult asthma. We report that mould contamination increased the risk of asthma, which is in agreement with existing knowledge. Exposure to mould contamination could not fully explain the association between increased energy efficiency and asthma. Our findings may be explained by increased energy efficiency combined with the provision of inadequate heating, ventilation, and increased concentrations of other biological, chemical and physical contaminants. This is likely to be modified by a complex interaction between occupant behaviours and changes to the built environment. Our findings may also be confounded by our response rate, demographic and behavioural differences between those residing in low versus high energy efficient homes, and use of self-reported exposures and outcomes. Energy efficiency may increase the risk of current adult asthma in a population residing in social housing. This association was not significantly modified by the presence of visible mould growth, although further research is needed to investigate the interaction between other demographic and housing characteristic risk factors, especially the impact of fuel poverty on indoor exposures and health outcomes. A multidisciplinary approach is required to assess the interaction between energy efficiency measures and fuel poverty behaviours on health outcomes prior to the delivery of physical interventions aimed at improving the built environment. Policy incentives are required to address fuel poverty issues alongside measures to achieve SAP ratings of 71 or greater, which must be delivered with the provision of adequate heating and ventilation strategies to minimise indoor dampness. Changes in the built environment without changes in behaviour of domicile residents may lead to negative health outcomes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Application of porous medium for efficiency improvement of a concentrated solar air heating system

NASA Astrophysics Data System (ADS)

Prasartkaew, Boonrit

2018-01-01

The objective of this study is to evaluate the thermal efficiency of a concentrated solar collector for a high temperature air heating system. The proposed system consists of a 25-m2 focused multi-flat-mirror solar heliostat equipped with a porous medium solar collector/receiver which was installed on the top of a 3-m tower, called ‘tower receiver’. To know how the system efficiency cloud be improved by using porous medium, the proposed system with and without porous medium were tested and the comparative study was performed. The experimental results reveal that, for the proposed system, application of porous medium is promising, the efficiency can be increased about 2 times compared to the conventional one. In addition, due to the porous medium used in this study was the waste material with very low cost. It can be summarized that the substantial efficiency improvement with very low investment cost of the proposed system seem to be a vital measures for addressing the energy issues.

An Energy-Efficient Algorithm for Wearable Electrocardiogram Signal Processing in Ubiquitous Healthcare Applications

PubMed Central

Sodhro, Ali Hassan; Sodhro, Gul Hassan; Lohano, Sonia; Pirbhulal, Sandeep

2018-01-01

Rapid progress and emerging trends in miniaturized medical devices have enabled the un-obtrusive monitoring of physiological signals and daily activities of everyone’s life in a prominent and pervasive manner. Due to the power-constrained nature of conventional wearable sensor devices during ubiquitous sensing (US), energy-efficiency has become one of the highly demanding and debatable issues in healthcare. This paper develops a single chip-based wearable wireless electrocardiogram (ECG) monitoring system by adopting analog front end (AFE) chip model ADS1292R from Texas Instruments. The developed chip collects real-time ECG data with two adopted channels for continuous monitoring of human heart activity. Then, these two channels and the AFE are built into a right leg drive right leg drive (RLD) driver circuit with lead-off detection and medical graded test signal. Human ECG data was collected at 60 beats per minute (BPM) to 120 BPM with 60 Hz noise and considered throughout the experimental set-up. Moreover, notch filter (cutoff frequency 60 Hz), high-pass filter (cutoff frequency 0.67 Hz), and low-pass filter (cutoff frequency 100 Hz) with cut-off frequencies of 60 Hz, 0.67 Hz, and 100 Hz, respectively, were designed with bilinear transformation for rectifying the power-line noise and artifacts while extracting real-time ECG signals. Finally, a transmission power control-based energy-efficient (ETPC) algorithm is proposed, implemented on the hardware and then compared with the several conventional TPC methods. Experimental results reveal that our developed chip collects real-time ECG data efficiently, and the proposed ETPC algorithm achieves higher energy savings of 35.5% with a slightly larger packet loss ratio (PLR) as compared to conventional TPC (e.g., constant TPC, Gao’s, and Xiao’s methods). PMID:29558433

An Energy-Efficient Algorithm for Wearable Electrocardiogram Signal Processing in Ubiquitous Healthcare Applications.

PubMed

Sodhro, Ali Hassan; Sangaiah, Arun Kumar; Sodhro, Gul Hassan; Lohano, Sonia; Pirbhulal, Sandeep

2018-03-20

Rapid progress and emerging trends in miniaturized medical devices have enabled the un-obtrusive monitoring of physiological signals and daily activities of everyone's life in a prominent and pervasive manner. Due to the power-constrained nature of conventional wearable sensor devices during ubiquitous sensing (US), energy-efficiency has become one of the highly demanding and debatable issues in healthcare. This paper develops a single chip-based wearable wireless electrocardiogram (ECG) monitoring system by adopting analog front end (AFE) chip model ADS1292R from Texas Instruments. The developed chip collects real-time ECG data with two adopted channels for continuous monitoring of human heart activity. Then, these two channels and the AFE are built into a right leg drive right leg drive (RLD) driver circuit with lead-off detection and medical graded test signal. Human ECG data was collected at 60 beats per minute (BPM) to 120 BPM with 60 Hz noise and considered throughout the experimental set-up. Moreover, notch filter (cutoff frequency 60 Hz), high-pass filter (cutoff frequency 0.67 Hz), and low-pass filter (cutoff frequency 100 Hz) with cut-off frequencies of 60 Hz, 0.67 Hz, and 100 Hz, respectively, were designed with bilinear transformation for rectifying the power-line noise and artifacts while extracting real-time ECG signals. Finally, a transmission power control-based energy-efficient (ETPC) algorithm is proposed, implemented on the hardware and then compared with the several conventional TPC methods. Experimental results reveal that our developed chip collects real-time ECG data efficiently, and the proposed ETPC algorithm achieves higher energy savings of 35.5% with a slightly larger packet loss ratio (PLR) as compared to conventional TPC (e.g., constant TPC, Gao's, and Xiao's methods).

Interregional sharing of energy conservation targets in China: Efficiency and equity

NASA Astrophysics Data System (ADS)

Wei, Dan

Energy conservation is a long-term strategic policy in China to support its economic and social development. This policy strategy is important for saving resources, protecting the environment, and ensuring the secure supply of energy to all economic activities. However, energy conservation often involves large amounts of investment and may also have dampening impacts on some local and regional economies. Moreover, energy conservation and efficiency improvement have many features of a public good. Therefore, government policy and intervention play a strong role to foster regional efforts and cooperative interregional actions on this issue. This dissertation introduces and analyzes a promising policy instrument---an interregional energy conservation-quota trading system---to help China fulfill its national energy conservation objective in an efficient and equitable way. To analyze the workings of the energy conservation-quota trading system, trading entities are first determined. In this study, statistical analyses (principal component analysis and cluster analysis) are applied to identify regional aggregations of provinces of China to act as the trading units. The marginal energy conservation cost curves of these regions are developed using engineering-economic methods and regression analysis. Simulations of interregional conservation-quota trading are undertaken after China's conservation goals in 2010 are allocated among regions according to several equity criteria. Various equity criteria are applied and analyzed in this study because of the philosophical differences in the appropriate definition of the concept. The trading simulations yield several important findings. First, the introduction of an interregional quota trading system can minimize both regional net compliance costs and national total conservation costs, irrespective of how the conservation tasks are initially allocated among regions according to different equity rules. Second, regional welfare implications differ across the applications of various equity criteria. However, for the energy production-based sovereignty and egalitarian equity criteria, the poorest region (in terms of per capita gross regional product) can enjoy net profits from trading, while the clustered region of wealthy coastal provinces shoulders the highest cost. This indicates that a conservation-quota trading system applying these two equity criteria is consistent with the national strategy in China to reduce regional income disparities and to develop the interior and western less-developed regions of the country. Third, compared with trading among conventional regions, trading among statistically clustered regions can more sharply apply the equity criteria to burden sharing and utilize larger differences in marginal conservation costs between regions to achieve a lower total net cost for the country as a whole. In sum, this research develops a useful methodology and identifies an operational way to attain energy conservation targets in China. It offers insights for similar interregional burden-sharing or benefit-sharing policies for China in the future, such as greenhouse gas emission trading, which is closely related to the energy conservation issue.

Semiconductor Nanotechnology: Novel Materials and Devices for Electronics, Photonics, and Renewable Energy Applications

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

Goodnick, Stephen; Korkin, Anatoli; Krstic, Predrag S

2010-03-01

Electronic and photonic information technology and renewable energy alternatives, such as solar energy, fuel cells and batteries, have now reached an advanced stage in their development. Cost-effective improvements to current technological approaches have made great progress, but certain challenges remain. As feature sizes of the latest generations of electronic devices are approaching atomic dimensions, circuit speeds are now being limited by interconnect bottlenecks. This has prompted innovations such as the introduction of new materials into microelectronics manufacturing at an unprecedented rate and alternative technologies to silicon CMOS architectures. Despite the environmental impact of conventional fossil fuel consumption, the low costmore » of these energy sources has been a long-standing economic barrier to the development of alternative and more efficient renewable energy sources, fuel cells and batteries. In the face of mounting environmental concerns, interest in such alternative energy sources has grown. It is now widely accepted that nanotechnology offers potential solutions for securing future progress in information and energy technologies. The Canadian Semiconductor Technology Conference (CSTC) forum was established 25 years ago in Ottawa as an important symbol of the intrinsic strength of the Canadian semiconductor research and development community, and the Canadian semiconductor industry as a whole. In 2007, the 13th CSTC was held in Montreal, moving for the first time outside the national capital region. The first three meetings in the series of Nano and Giga Challenges in Electronics and Photonics NGCM2002 in Moscow, NGCM2004 in Krakow, and NGC2007 in Phoenix were focused on interdisciplinary research from the fundamentals of materials science to the development of new system architectures. In 2009 NGC2009 and the 14th Canadian Semiconductor Technology Conference (CSTC2009) were held as a joint event, hosted by McMaster University (10 14 August, Hamilton, Ontario, Canada) and the scope was expanded to include renewable energy research and development. This special issue of Nanotechnology is devoted to a better understanding of the function and design of semiconductor devices that are relevant to information technology (both electronics and photonics based) and renewable energy applications. The papers contained in this special issue are selected from the NGC/CSTC2009 symposium. Among them is a report by Ray LaPierre from McMaster University and colleagues at the University of Waterloo in Canada on the ability to manipulate single spins in nanowire quantum bits. The paper also reports the development of a testbed of a few qubits for general quantum information processing tasks [1]. Lower cost and greater energy conversion efficiency compared with thin film devices have led to a high level of activity in nanowire research related to photovoltaic applications. This special issue also contains results from an impedance spectroscopy study of core shell GaAs nanowires to throw light on the transport and recombination mechanisms relevant to solar cell research [2]. Information technology research and renewable energy sources are research areas of enormous public interest. This special issue addresses both theoretical and experimental achievements and provides a stimulating outlook for technological developments in these highly topical fields of research. References [1] Caram J, Sandoval C, Tirado M, Comedi D, Czaban J, Thompson D A and LaPierre R R 2010 Electrical characteristics of core shell p-n GaAs nanowire structures with Te as the n-dopant Nanotechnology 21 134007 [2] Baugh J, Fung J S and LaPierre R R 2010 Building a spin quantum bit register using semiconductor nanowires Nanotechnology 21 134018« less