Revisiting control establishments for emerging energy hubs

NASA Astrophysics Data System (ADS)

Nasirian, Vahidreza

Emerging small-scale energy systems, i.e., microgrids and smartgrids, rely on centralized controllers for voltage regulation, load sharing, and economic dispatch. However, the central controller is a single-point-of-failure in such a design as either the controller or attached communication links failure can render the entire system inoperable. This work seeks for alternative distributed control structures to improve system reliability and help to the scalability of the system. A cooperative distributed controller is proposed that uses a noise-resilient voltage estimator and handles global voltage regulation and load sharing across a DC microgrid. Distributed adaptive droop control is also investigated as an alternative solution. A droop-free distributed control is offered to handle voltage/frequency regulation and load sharing in AC systems. This solution does not require frequency measurement and, thus, features a fast frequency regulation. Distributed economic dispatch is also studied, where a distributed protocol is designed that controls generation units to merge their incremental costs into a consensus and, thus, push the entire system to generate with the minimum cost. Experimental verifications and Hardware-in-the-Loop (HIL) simulations are used to study efficacy of the proposed control protocols.

Economic Analysis Case Studies of Battery Energy Storage with SAM

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

DiOrio, Nicholas; Dobos, Aron; Janzou, Steven

2015-11-01

Interest in energy storage has continued to increase as states like California have introduced mandates and subsidies to spur adoption. This energy storage includes customer sited behind-the-meter storage coupled with photovoltaics (PV). This paper presents case study results from California and Tennessee, which were performed to assess the economic benefit of customer-installed systems. Different dispatch strategies, including manual scheduling and automated peak-shaving were explored to determine ideal ways to use the storage system to increase the system value and mitigate demand charges. Incentives, complex electric tariffs, and site specific load and PV data were used to perform detailed analysis. Themore » analysis was performed using the free, publically available System Advisor Model (SAM) tool. We find that installation of photovoltaics with a lithium-ion battery system priced at $300/kWh in Los Angeles under a high demand charge utility rate structure and dispatched using perfect day-ahead forecasting yields a positive net-present value, while all other scenarios cost the customer more than the savings accrued. Different dispatch strategies, including manual scheduling and automated peak-shaving were explored to determine ideal ways to use the storage system to increase the system value and mitigate demand charges. Incentives, complex electric tariffs, and site specific load and PV data were used to perform detailed analysis. The analysis was performed using the free, publically available System Advisor Model (SAM) tool. We find that installation of photovoltaics with a lithium-ion battery system priced at $300/kWh in Los Angeles under a high demand charge utility rate structure and dispatched using perfect day-ahead forecasting yields a positive net-present value, while all other scenarios cost the customer more than the savings accrued.« less

Near-term implications of a ban on new coal-fired power plants in the United States.

PubMed

Newcomer, Adam; Apt, Jay

2009-06-01

Large numbers of proposed new coal power generators in the United States have been canceled, and some states have prohibited new coal power generators. We examine the effects on the U.S. electric power system of banning the construction of coal-fired electricity generators, which has been proposed as a means to reduce U.S. CO2 emissions. The model simulates load growth, resource planning, and economic dispatch of the Midwest Independent Transmission System Operator (ISO), Inc., Electric Reliability Council of Texas (ERCOT), and PJM under a ban on new coal generation and uses an economic dispatch model to calculate the resulting changes in dispatch order, CO2 emissions, and fuel use under three near-term (until 2030) future electric power sector scenarios. A national ban on new coal-fired power plants does not lead to CO2 reductions of the scale required under proposed federal legislation such as Lieberman-Warner but would greatly increase the fraction of time when natural gas sets the price of electricity, even with aggressive wind and demand response policies.

View west of load dispatch model board; section covers substations ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View west of load dispatch model board; section covers substations from edgerly (right) to thorndale and west yard (left). Instruments at bottom of center board section formerly monitored energy usage and were replaced by a computerized monitoring system. - Thirtieth Street Station, Load Dispatch Center, Thirtieth & Market Streets, Railroad Station, Amtrak (formerly Pennsylvania Railroad Station), Philadelphia, Philadelphia County, PA

Heat Transfer Search Algorithm for Non-convex Economic Dispatch Problems

NASA Astrophysics Data System (ADS)

Hazra, Abhik; Das, Saborni; Basu, Mousumi

2018-06-01

This paper presents Heat Transfer Search (HTS) algorithm for the non-linear economic dispatch problem. HTS algorithm is based on the law of thermodynamics and heat transfer. The proficiency of the suggested technique has been disclosed on three dissimilar complicated economic dispatch problems with valve point effect; prohibited operating zone; and multiple fuels with valve point effect. Test results acquired from the suggested technique for the economic dispatch problem have been fitted to that acquired from other stated evolutionary techniques. It has been observed that the suggested HTS carry out superior solutions.

Heat Transfer Search Algorithm for Non-convex Economic Dispatch Problems

NASA Astrophysics Data System (ADS)

Hazra, Abhik; Das, Saborni; Basu, Mousumi

2018-03-01

This paper presents Heat Transfer Search (HTS) algorithm for the non-linear economic dispatch problem. HTS algorithm is based on the law of thermodynamics and heat transfer. The proficiency of the suggested technique has been disclosed on three dissimilar complicated economic dispatch problems with valve point effect; prohibited operating zone; and multiple fuels with valve point effect. Test results acquired from the suggested technique for the economic dispatch problem have been fitted to that acquired from other stated evolutionary techniques. It has been observed that the suggested HTS carry out superior solutions.

Stochastic Multi-Timescale Power System Operations With Variable Wind Generation

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

Wu, Hongyu; Krad, Ibrahim; Florita, Anthony

This paper describes a novel set of stochastic unit commitment and economic dispatch models that consider stochastic loads and variable generation at multiple operational timescales. The stochastic model includes four distinct stages: stochastic day-ahead security-constrained unit commitment (SCUC), stochastic real-time SCUC, stochastic real-time security-constrained economic dispatch (SCED), and deterministic automatic generation control (AGC). These sub-models are integrated together such that they are continually updated with decisions passed from one to another. The progressive hedging algorithm (PHA) is applied to solve the stochastic models to maintain the computational tractability of the proposed models. Comparative case studies with deterministic approaches are conductedmore » in low wind and high wind penetration scenarios to highlight the advantages of the proposed methodology, one with perfect forecasts and the other with current state-of-the-art but imperfect deterministic forecasts. The effectiveness of the proposed method is evaluated with sensitivity tests using both economic and reliability metrics to provide a broader view of its impact.« less

View west within the periphery of the load dispatch model ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View west within the periphery of the load dispatch model board, operator's console is at lower center and button board is at lower right of the photograph; section of model board shown covers substation from Perryman (left) to Frankford (right); instruments at right center of photograph formerly monitored energy usage and were replaced by computerized monitoring system. - Thirtieth Street Station, Load Dispatch Center, Thirtieth & Market Streets, Railroad Station, Amtrak (formerly Pennsylvania Railroad Station), Philadelphia, Philadelphia County, PA

Near-term implications of a ban on new coal-fired power plants in the United States

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

Adam Newcomer; Jay Apt

2009-06-15

Large numbers of proposed new coal power generators in the United States have been cancelled, and some states have prohibited new coal power generators. We examine the effects on the U.S. electric power system of banning the construction of coal-fired electricity generators, which has been proposed as a means to reduce U.S. CO{sub 2} emissions. The model simulates load growth, resource planning, and economic dispatch of the Midwest Independent Transmission System Operator (ISO), Inc., Electric Reliability Council of Texas (ERCOT), and PJM under a ban on new coal generation and uses an economic dispatch model to calculate the resulting changesmore » in dispatch order, CO{sub 2} emissions, and fuel use under three near-term (until 2030) future electric power sector scenarios. A national ban on new coal-fired power plants does not lead to CO{sub 2} reductions of the scale required under proposed federal legislation such as Lieberman-Warner but would greatly increase the fraction of time when natural gas sets the price of electricity, even with aggressive wind and demand response policies. 50 refs., 5 figs., 4 tabs.« less

Dispatch Strategy Development for Grid-tied Household Energy Systems

NASA Astrophysics Data System (ADS)

Cardwell, Joseph

The prevalence of renewable generation will increase in the next several decades and offset conventional generation more and more. Yet this increase is not coming without challenges. Solar, wind, and even some water resources are intermittent and unpredictable, and thereby create scheduling challenges due to their inherent "uncontrolled" nature. To effectively manage these distributed renewable assets, new control algorithms must be developed for applications including energy management, bridge power, and system stability. This can be completed through a centralized control center though efforts are being made to parallel the control architecture with the organization of the renewable assets themselves--namely, distributed controls. Building energy management systems are being employed to control localized energy generation, storage, and use to reduce disruption on the net utility load. One such example is VOLTTRONTM, an agent-based platform for building energy control in real time. In this thesis, algorithms developed in VOLTTRON simulate a home energy management system that consists of a solar PV array, a lithium-ion battery bank, and the grid. Dispatch strategies are implemented to reduce energy charges from overall consumption (/kWh) and demand charges (/kW). Dispatch strategies for implementing storage devices are tuned on a month-to-month basis to provide a meaningful economic advantage under simulated scenarios to explore algorithm sensitivity to changing external factors. VOLTTRON agents provide automated real-time optimization of dispatch strategies to efficiently manage energy supply and demand, lower consumer costs associated with energy usage, and reduce load on the utility grid.

Hybrid robust predictive optimization method of power system dispatch

DOEpatents

Chandra, Ramu Sharat [Niskayuna, NY; Liu, Yan [Ballston Lake, NY; Bose, Sumit [Niskayuna, NY; de Bedout, Juan Manuel [West Glenville, NY

2011-08-02

A method of power system dispatch control solves power system dispatch problems by integrating a larger variety of generation, load and storage assets, including without limitation, combined heat and power (CHP) units, renewable generation with forecasting, controllable loads, electric, thermal and water energy storage. The method employs a predictive algorithm to dynamically schedule different assets in order to achieve global optimization and maintain the system normal operation.

Minimum-Time Consensus-Based Approach for Power System Applications

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

Yang, Tao; Wu, Di; Sun, Yannan

2016-02-01

This paper presents minimum-time consensus based distributed algorithms for power system applications, such as load shedding and economic dispatch. The proposed algorithms are capable of solving these problems in a minimum number of time steps instead of asymptotically as in most of existing studies. Moreover, these algorithms are applicable to both undirected and directed communication networks. Simulation results are used to validate the proposed algorithms.

Self-Organizing Hierarchical Particle Swarm Optimization with Time-Varying Acceleration Coefficients for Economic Dispatch with Valve Point Effects and Multifuel Options

NASA Astrophysics Data System (ADS)

Polprasert, Jirawadee; Ongsakul, Weerakorn; Dieu, Vo Ngoc

2011-06-01

This paper proposes a self-organizing hierarchical particle swarm optimization (SPSO) with time-varying acceleration coefficients (TVAC) for solving economic dispatch (ED) problem with non-smooth functions including multiple fuel options (MFO) and valve-point loading effects (VPLE). The proposed SPSO with TVAC is the new approach optimizer and good performance for solving ED problems. It can handle the premature convergence of the problem by re-initialization of velocity whenever particles are stagnated in the search space. To properly control both local and global explorations of the swarm during the optimization process, the performance of TVAC is included. The proposed method is tested in different ED problems with non-smooth cost functions and the obtained results are compared to those from many other methods in the literature. The results have revealed that the proposed SPSO with TVAC is effective in finding higher quality solutions for non-smooth ED problems than many other methods.

Refined genetic algorithm -- Economic dispatch example

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

Sheble, G.B.; Brittig, K.

1995-02-01

A genetic-based algorithm is used to solve an economic dispatch (ED) problem. The algorithm utilizes payoff information of perspective solutions to evaluate optimality. Thus, the constraints of classical LaGrangian techniques on unit curves are eliminated. Using an economic dispatch problem as a basis for comparison, several different techniques which enhance program efficiency and accuracy, such as mutation prediction, elitism, interval approximation and penalty factors, are explored. Two unique genetic algorithms are also compared. The results are verified for a sample problem using a classical technique.

Flexible Energy Scheduling Tool for Integrating Variable Generation | Grid

Science.gov Websites

, security-constrained economic dispatch, and automatic generation control programs. DOWNLOAD PAPER Electric commitment, security-constrained economic dispatch, and automatic generation control sub-models. Each sub resolutions and operating strategies can be explored. FESTIV produces not only economic metrics but also

Sample EP Flow Analysis of Severely Damaged Networks

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

Werley, Kenneth Alan; McCown, Andrew William

These are slides for a presentation at the working group meeting of the WESC SREMP Software Product Integration Team on sample EP flow analysis of severely damaged networks. The following topics are covered: ERCOT EP Transmission Model; Zoomed in to Houston and Overlaying StreetAtlas; EMPACT Solve/Dispatch/Shedding Options; QACS BaseCase Power Flow Solution; 3 Substation Contingency; Gen. & Load/100 Optimal Dispatch; Dispatch Results; Shed Load for Low V; Network Damage Summary; Estimated Service Areas (Potential); Estimated Outage Areas (potential).

Instituto Nacional de Electrification, Guatemala Load Dispatch Center and Global Communications Center. Feasibility report (Instituto Nacional de Electrificacion, Guatemala Centro Nacional de Despacho de Carga y Sistema Global de Comunicaciones). Export trade information

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

Not Available

1985-07-01

The report presents the results of a feasibility study for the National Load Dispatch Center and Global Communications System Project in Guatemala. The project consists of a communication system which will provide Institute Nacional de Electrificacion (INDE) operations personnel direct voice access to all major power system facilities. In addition, a modern computer based load dispatch center has been configured on a secure and reliable basis to provide automatic generation control of all major interconnected generating plants within Guatemala.

View southeast of computer controlled energy monitoring system. System replaced ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View southeast of computer controlled energy monitoring system. System replaced strip chart recorders and other instruments under the direct observation of the load dispatcher. - Thirtieth Street Station, Load Dispatch Center, Thirtieth & Market Streets, Railroad Station, Amtrak (formerly Pennsylvania Railroad Station), Philadelphia, Philadelphia County, PA

A review on economic emission dispatch problems using quantum computational intelligence

NASA Astrophysics Data System (ADS)

Mahdi, Fahad Parvez; Vasant, Pandian; Kallimani, Vish; Abdullah-Al-Wadud, M.

2016-11-01

Economic emission dispatch (EED) problems are one of the most crucial problems in power systems. Growing energy demand, limitation of natural resources and global warming make this topic into the center of discussion and research. This paper reviews the use of Quantum Computational Intelligence (QCI) in solving Economic Emission Dispatch problems. QCI techniques like Quantum Genetic Algorithm (QGA) and Quantum Particle Swarm Optimization (QPSO) algorithm are discussed here. This paper will encourage the researcher to use more QCI based algorithm to get better optimal result for solving EED problems.

Real-Time Dispatch of Petroleum Tank Trucks.

DTIC Science & Technology

1979-12-01

dispatches for each bulk terminal from which loads are hauled. The dispatchers, located at a central national order processing facility, must each...of an order processor and new capa- bilities to, for instance, trace orders. Also, uniform control of thef order processing function is desirable, if

Multi-objective generation scheduling with hybrid energy resources

NASA Astrophysics Data System (ADS)

Trivedi, Manas

In economic dispatch (ED) of electric power generation, the committed generating units are scheduled to meet the load demand at minimum operating cost with satisfying all unit and system equality and inequality constraints. Generation of electricity from the fossil fuel releases several contaminants into the atmosphere. So the economic dispatch objective can no longer be considered alone due to the environmental concerns that arise from the emissions produced by fossil fueled electric power plants. This research is proposing the concept of environmental/economic generation scheduling with traditional and renewable energy sources. Environmental/economic dispatch (EED) is a multi-objective problem with conflicting objectives since emission minimization is conflicting with fuel cost minimization. Production and consumption of fossil fuel and nuclear energy are closely related to environmental degradation. This causes negative effects to human health and the quality of life. Depletion of the fossil fuel resources will also be challenging for the presently employed energy systems to cope with future energy requirements. On the other hand, renewable energy sources such as hydro and wind are abundant, inexhaustible and widely available. These sources use native resources and have the capacity to meet the present and the future energy demands of the world with almost nil emissions of air pollutants and greenhouse gases. The costs of fossil fuel and renewable energy are also heading in opposite directions. The economic policies needed to support the widespread and sustainable markets for renewable energy sources are rapidly evolving. The contribution of this research centers on solving the economic dispatch problem of a system with hybrid energy resources under environmental restrictions. It suggests an effective solution of renewable energy to the existing fossil fueled and nuclear electric utilities for the cheaper and cleaner production of electricity with hourly emission targets. Since minimizing the emissions and fuel cost are conflicting objectives, a practical approach based on multi-objective optimization is applied to obtain compromised solutions in a single simulation run using genetic algorithm. These solutions are known as non-inferior or Pareto-optimal solutions, graphically illustrated by the trade-off curves between criterions fuel cost and pollutant emission. The efficacy of the proposed approach is illustrated with the help of different sample test cases. This research would be useful for society, electric utilities, consultants, regulatory bodies, policy makers and planners.

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

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

Long, Matthew; Simpkins, Travis; Cutler, Dylan

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

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

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

Long, Matthew; Simpkins, Travis; Cutler, Dylan

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

Collective neurodynamic optimization for economic emission dispatch problem considering valve point effect in microgrid.

PubMed

Wang, Tiancai; He, Xing; Huang, Tingwen; Li, Chuandong; Zhang, Wei

2017-09-01

The economic emission dispatch (EED) problem aims to control generation cost and reduce the impact of waste gas on the environment. It has multiple constraints and nonconvex objectives. To solve it, the collective neurodynamic optimization (CNO) method, which combines heuristic approach and projection neural network (PNN), is attempted to optimize scheduling of an electrical microgrid with ten thermal generators and minimize the plus of generation and emission cost. As the objective function has non-derivative points considering valve point effect (VPE), differential inclusion approach is employed in the PNN model introduced to deal with them. Under certain conditions, the local optimality and convergence of the dynamic model for the optimization problem is analyzed. The capability of the algorithm is verified in a complicated situation, where transmission loss and prohibited operating zones are considered. In addition, the dynamic variation of load power at demand side is considered and the optimal scheduling of generators within 24 h is described. Copyright © 2017 Elsevier Ltd. All rights reserved.

System dynamics model of taxi management in metropolises: Economic and environmental implications for Beijing.

PubMed

Wang, Hao; Zhang, Kai; Chen, Junhua; Wang, Zhifeng; Li, Guijun; Yang, Yuqi

2018-05-01

Taxis are an important component of urban passenger transport. Research on the daily dispatching of taxis and the utility of governmental management is important for the improvement of passenger travel, taxi driver income and environmental impacts. However, urban taxi management is a complex and dynamic system that is affected by many factors, and positive/negative feedback relationships and nonlinear interactions exist between each subsystem and variable. Therefore, conventional research methods can hardly depict its characteristics comprehensively. To bridge this gap, this paper develops a system dynamics model of urban taxi management, in which the empty-loaded rate and total demand are selected as key factors affecting taxi dispatching, and the impacts of taxi fares on driver income and travel demand are taken into account. After the validation of the model, taxi operations data derived from a prior analysis of origin-destination data of Beijing taxis are used as input for the model to simulate the taxi market in Beijing. Finally, economic and environmental implications are provided for the government to optimise policies on taxi management. Copyright © 2018 Elsevier Ltd. All rights reserved.

TLBO based Voltage Stable Environment Friendly Economic Dispatch Considering Real and Reactive Power Constraints

NASA Astrophysics Data System (ADS)

Verma, H. K.; Mafidar, P.

2013-09-01

In view of growing concern towards environment, power system engineers are forced to generate quality green energy. Hence the economic dispatch (ED) aims at the power generation to meet the load demand at minimum fuel cost with environmental and voltage constraints along with essential constraints on real and reactive power. The emission control which reduces the negative impact on environment is achieved by including the additional constraints in ED problem. Presently, the power system mostly operates near its stability limits, therefore with increased demand the system faces voltage problem. The bus voltages are brought within limit in the present work by placement of static var compensator (SVC) at weak bus which is identified from bus participation factor. The optimal size of SVC is determined by univariate search method. This paper presents the use of Teaching Learning based Optimization (TLBO) algorithm for voltage stable environment friendly ED problem with real and reactive power constraints. The computational effectiveness of TLBO is established through test results over particle swarm optimization (PSO) and Big Bang-Big Crunch (BB-BC) algorithms for the ED problem.

Multi-objective optimal dispatch of distributed energy resources

NASA Astrophysics Data System (ADS)

Longe, Ayomide

This thesis is composed of two papers which investigate the optimal dispatch for distributed energy resources. In the first paper, an economic dispatch problem for a community microgrid is studied. In this microgrid, each agent pursues an economic dispatch for its personal resources. In addition, each agent is capable of trading electricity with other agents through a local energy market. In this paper, a simple market structure is introduced as a framework for energy trades in a small community microgrid such as the Solar Village. It was found that both sellers and buyers benefited by participating in this market. In the second paper, Semidefinite Programming (SDP) for convex relaxation of power flow equations is used for optimal active and reactive dispatch for Distributed Energy Resources (DER). Various objective functions including voltage regulation, reduced transmission line power losses, and minimized reactive power charges for a microgrid are introduced. Combinations of these goals are attained by solving a multiobjective optimization for the proposed ORPD problem. Also, both centralized and distributed versions of this optimal dispatch are investigated. It was found that SDP made the optimal dispatch faster and distributed solution allowed for scalability.

Research on intelligent power consumption strategy based on time-of-use pricing

NASA Astrophysics Data System (ADS)

Fu, Wei; Gong, Li; Chen, Heli; He, Yu

2017-06-01

In this paper, through the analysis of shortcomings of the current domestic and foreign household power consumption strategy: Passive way of power consumption, ignoring the different priority of electric equipment, neglecting the actual load pressure of the grid, ignoring the interaction with the user, to decrease the peak-valley difference and improve load curve in residential area by demand response (DR technology), an intelligent power consumption scheme based on time-of-use(TOU) pricing for household appliances is proposed. The main contribution of this paper is: (1) Three types of household appliance loads are abstracted from different operating laws of various household appliances, and the control models and DR strategies corresponding to these types are established. (2) The fuzzified processing for the information of TOU price, which is based on the time intervals, is performed to get the price priority, in accordance with such DR events as the maximum restricted load of DR, the time of DR and the duration of interruptible load and so on, the DR control rule and pre-scheduling mechanism are led in. (3) The dispatching sequence of household appliances in the control and scheduling queue are switched and controlled to implement the equilibrium of peak and valley loads. The equilibrium effects and economic benefits of power system by pre-scheduling and DR dispatching are compared and analyzed by simulation example, and the results show that using the proposed household appliance control (HAC) scheme the overall cost of consumers can be reduced and the power system load can be alleviated, so the proposed household appliance control (HAC) scheme is feasible and reasonable.

Innovative telecommunications for law enforcement

NASA Technical Reports Server (NTRS)

Sohn, R. L.

1976-01-01

The operation of computer-aided dispatch, mobile digital communications, and automatic vehicle location systems used in law enforcement is discussed, and characteristics of systems used by different agencies are compared. With reference to computer-aided dispatch systems, the data base components, dispatcher work load, extent of usage, and design trends are surveyed. The capabilities, levels of communication, and traffic load of mobile digital communications systems are examined. Different automatic vehicle location systems are distinguished, and two systems are evaluated. Other aspects of the application of innovative technology to operational command, control, and communications systems for law enforcement agencies are described.

Calculation and application of energy transaction allocation factors in electric power transmission systems

NASA Astrophysics Data System (ADS)

Fradi, Aniss

The ability to allocate the active power (MW) loading on transmission lines and transformers, is the basis of the "flow based" transmission allocation system developed by the North American Electric Reliability Council. In such a system, the active power flows must be allocated to each line or transformer in proportion to the active power being transmitted by each transaction imposed on the system. Currently, this is accomplished through the use of the linear Power Transfer Distribution Factors (PTDFs). Unfortunately, no linear allocation models exist for other energy transmission quantities, such as MW and MVAR losses, MVAR and MVA flows, etc. Early allocation schemes were developed to allocate MW losses due to transactions to branches in a transmission system, however they exhibited diminished accuracy, since most of them are based on linear power flow modeling of the transmission system. This thesis presents a new methodology to calculate Energy Transaction Allocation factors (ETA factors, or eta factors), using the well-known process of integration of a first derivative function, as well as consistent and well-established mathematical and AC power flow models. The factors give a highly accurate allocation of any non-linear system quantity to transactions placed on the transmission system. The thesis also extends the new ETA factors calculation procedure to restructure a new economic dispatch scheme where multiple sets of generators are economically dispatched to meet their corresponding load and their share of the losses.

Impact of Uncertainty from Load-Based Reserves and Renewables on Dispatch Costs and Emissions

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

Li, Bowen; Maroukis, Spencer D.; Lin, Yashen

2016-11-21

Aggregations of controllable loads are considered to be a fast-responding, cost-efficient, and environmental-friendly candidate for power system ancillary services. Unlike conventional service providers, the potential capacity from the aggregation is highly affected by factors like ambient conditions and load usage patterns. Previous work modeled aggregations of controllable loads (such as air conditioners) as thermal batteries, which are capable of providing reserves but with uncertain capacity. A stochastic optimal power flow problem was formulated to manage this uncertainty, as well as uncertainty in renewable generation. In this paper, we explore how the types and levels of uncertainty, generation reserve costs, andmore » controllable load capacity affect the dispatch solution, operational costs, and CO2 emissions. We also compare the results of two methods for solving the stochastic optimization problem, namely the probabilistically robust method and analytical reformulation assuming Gaussian distributions. Case studies are conducted on a modified IEEE 9-bus system with renewables, controllable loads, and congestion. We find that different types and levels of uncertainty have significant impacts on dispatch and emissions. More controllable loads and less conservative solution methodologies lead to lower costs and emissions.« less

Chance-constrained economic dispatch with renewable energy and storage

DOE PAGES

Cheng, Jianqiang; Chen, Richard Li-Yang; Najm, Habib N.; ...

2018-04-19

Increased penetration of renewables, along with uncertainties associated with them, have transformed how power systems are operated. High levels of uncertainty means that it is not longer possible to guarantee operational feasibility with certainty, instead constraints are required to be satisfied with high probability. We present a chance-constrained economic dispatch model that efficiently integrates energy storage and high renewable penetration to satisfy renewable portfolio requirements. Specifically, it is required that wind energy contributes at least a prespecified ratio of the total demand and that the scheduled wind energy is dispatchable with high probability. We develop an approximated partial sample averagemore » approximation (PSAA) framework to enable efficient solution of large-scale chanceconstrained economic dispatch problems. Computational experiments on the IEEE-24 bus system show that the proposed PSAA approach is more accurate, closer to the prescribed tolerance, and about 100 times faster than sample average approximation. Improved efficiency of our PSAA approach enables solution of WECC-240 system in minutes.« less

Chance-constrained economic dispatch with renewable energy and storage

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

Cheng, Jianqiang; Chen, Richard Li-Yang; Najm, Habib N.

Increased penetration of renewables, along with uncertainties associated with them, have transformed how power systems are operated. High levels of uncertainty means that it is not longer possible to guarantee operational feasibility with certainty, instead constraints are required to be satisfied with high probability. We present a chance-constrained economic dispatch model that efficiently integrates energy storage and high renewable penetration to satisfy renewable portfolio requirements. Specifically, it is required that wind energy contributes at least a prespecified ratio of the total demand and that the scheduled wind energy is dispatchable with high probability. We develop an approximated partial sample averagemore » approximation (PSAA) framework to enable efficient solution of large-scale chanceconstrained economic dispatch problems. Computational experiments on the IEEE-24 bus system show that the proposed PSAA approach is more accurate, closer to the prescribed tolerance, and about 100 times faster than sample average approximation. Improved efficiency of our PSAA approach enables solution of WECC-240 system in minutes.« less

Short-Term Load Forecasting Error Distributions and Implications for Renewable Integration Studies: Preprint

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

Hodge, B. M.; Lew, D.; Milligan, M.

2013-01-01

Load forecasting in the day-ahead timescale is a critical aspect of power system operations that is used in the unit commitment process. It is also an important factor in renewable energy integration studies, where the combination of load and wind or solar forecasting techniques create the net load uncertainty that must be managed by the economic dispatch process or with suitable reserves. An understanding of that load forecasting errors that may be expected in this process can lead to better decisions about the amount of reserves necessary to compensate errors. In this work, we performed a statistical analysis of themore » day-ahead (and two-day-ahead) load forecasting errors observed in two independent system operators for a one-year period. Comparisons were made with the normal distribution commonly assumed in power system operation simulations used for renewable power integration studies. Further analysis identified time periods when the load is more likely to be under- or overforecast.« less

Power management of remote microgrids considering battery lifetime

NASA Astrophysics Data System (ADS)

Chalise, Santosh

Currently, 20% (1.3 billion) of the world's population still lacks access to electricity and many live in remote areas where connection to the grid is not economical or practical. Remote microgrids could be the solution to the problem because they are designed to provide power for small communities within clearly defined electrical boundaries. Reducing the cost of electricity for remote microgrids can help to increase access to electricity for populations in remote areas and developing countries. The integration of renewable energy and batteries in diesel based microgrids has shown to be effective in reducing fuel consumption. However, the operational cost remains high due to the low lifetime of batteries, which are heavily used to improve the system's efficiency. In microgrid operation, a battery can act as a source to augment the generator or a load to ensure full load operation. In addition, a battery increases the utilization of PV by storing extra energy. However, the battery has a limited energy throughput. Therefore, it is required to provide balance between fuel consumption and battery lifetime throughput in order to lower the cost of operation. This work presents a two-layer power management system for remote microgrids. First layer is day ahead scheduling, where power set points of dispatchable resources were calculated. Second layer is real time dispatch, where schedule set points from the first layer are accepted and resources are dispatched accordingly. A novel scheduling algorithm is proposed for a dispatch layer, which considers the battery lifetime in optimization and is expected to reduce the operational cost of the microgrid. This method is based on a goal programming approach which has the fuel and the battery wear cost as two objectives to achieve. The effectiveness of this method was evaluated through a simulation study of a PV-diesel hybrid microgrid using deterministic and stochastic approach of optimization.

REopt Lite Web Tool Evaluates Photovoltaics and Battery Storage

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

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

A Gaussian Processes Technique for Short-term Load Forecasting with Considerations of Uncertainty

NASA Astrophysics Data System (ADS)

Ohmi, Masataro; Mori, Hiroyuki

In this paper, an efficient method is proposed to deal with short-term load forecasting with the Gaussian Processes. Short-term load forecasting plays a key role to smooth power system operation such as economic load dispatching, unit commitment, etc. Recently, the deregulated and competitive power market increases the degree of uncertainty. As a result, it is more important to obtain better prediction results to save the cost. One of the most important aspects is that power system operator needs the upper and lower bounds of the predicted load to deal with the uncertainty while they require more accurate predicted values. The proposed method is based on the Bayes model in which output is expressed in a distribution rather than a point. To realize the model efficiently, this paper proposes the Gaussian Processes that consists of the Bayes linear model and kernel machine to obtain the distribution of the predicted value. The proposed method is successively applied to real data of daily maximum load forecasting.

Comparing post-combustion CO2 capture operation at retrofitted coal-fired power plants in the Texas and Great Britain electric grids

NASA Astrophysics Data System (ADS)

Cohen, Stuart M.; Chalmers, Hannah L.; Webber, Michael E.; King, Carey W.

2011-04-01

This work analyses the carbon dioxide (CO2) capture system operation within the Electric Reliability Council of Texas (ERCOT) and Great Britain (GB) electric grids using a previously developed first-order hourly electricity dispatch and pricing model. The grids are compared in their 2006 configuration with the addition of coal-based CO2 capture retrofits and emissions penalties from 0 to 100 US dollars per metric ton of CO2 (USD/tCO2). CO2 capture flexibility is investigated by comparing inflexible CO2 capture systems to flexible ones that can choose between full- and zero-load CO2 capture depending on which operating mode has lower costs or higher profits. Comparing these two grids is interesting because they have similar installed capacity and peak demand, and both are isolated electricity systems with competitive wholesale electricity markets. However, differences in capacity mix, demand patterns, and fuel markets produce diverging behaviours of CO2 capture at coal-fired power plants. Coal-fired facilities are primarily base load in ERCOT for a large range of CO2 prices but are comparably later in the dispatch order in GB and consequently often supply intermediate load. As a result, the ability to capture CO2 is more important for ensuring dispatch of coal-fired facilities in GB than in ERCOT when CO2 prices are high. In GB, higher overall coal prices mean that CO2 prices must be slightly higher than in ERCOT before the emissions savings of CO2 capture offset capture energy costs. However, once CO2 capture is economical, operating CO2 capture on half the coal fleet in each grid achieves greater emissions reductions in GB because the total coal-based capacity is 6 GW greater than in ERCOT. The market characteristics studied suggest greater opportunity for flexible CO2 capture to improve operating profits in ERCOT, but profit improvements can be offset by a flexibility cost penalty.

Performance modeling and techno-economic analysis of a modular concentrated solar power tower with latent heat storage

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

Rea, Jonathan E.; Oshman, Christopher J.; Olsen, Michele L.

In this paper, we present performance simulations and techno-economic analysis of a modular dispatchable solar power tower. Using a heliostat field and power block three orders of magnitude smaller than conventional solar power towers, our unique configuration locates thermal storage and a power block directly on a tower receiver. To make the system dispatchable, a valved thermosyphon controls heat flow from a latent heat thermal storage tank to a Stirling engine. The modular design results in minimal balance of system costs and enables high deployment rates with a rapid realization of economies of scale. In this new analysis, we combinemore » performance simulations with techno-economic analysis to evaluate levelized cost of electricity, and find that the system has potential for cost-competitiveness with natural gas peaking plants and alternative dispatchable renewables.« less

Inefficient power generation as an optimal route to negative emissions via BECCS?

NASA Astrophysics Data System (ADS)

Mac Dowell, Niall; Fajardy, Mathilde

2017-04-01

Current ambitions to limit climate change to no more than 1.5 °C-2 °C by the end of the 21st century rely heavily on the availability of negative emissions technologies (NETs)—bioenergy with CO2 capture and storage (BECCS) and direct air capture in particular. In this context, these NETs are providing a specific service by removing CO2 from the atmosphere, and therefore investors would expect an appropriate risk-adjusted rate of return, varying as a function of the quantity of public money involved. Uniquely, BECCS facilities have the possibility to generate both low carbon power and remove CO2 from the atmosphere, but in an energy system characterised by high penetration of intermittent renewable energy such as wind and solar power plants, the dispatch load factor of such BECCS facilities may be small relative to their capacity. This has the potential to significantly under utilise these assets for their primary purpose of removing CO2 from the atmosphere. In this study, we present a techno-economic environmental evaluation of BECCS plants with a range of operating efficiencies, considering their full- and part-load operation relative to a national-scale annual CO2 removal target. We find that in all cases, a lower capital cost, lower efficiency BECCS plant is superior to a higher cost, higher efficiency facility from both environmental and economic perspectives. We show that it may be preferable to operate the BECCS facility in base-load fashion, constantly removing CO2 from the atmosphere and dispatching electricity on an as-needed basis. We show that the use of this ‘spare capacity’ to produce hydrogen for, e.g. injection to a natural gas system for the provision of low carbon heating can add to the overall environmental and economic benefit of such a system. The only point where this hypothesis appears to break down is where the CO2 emissions associated with the biomass supply chain are sufficiently large so as to eliminate the service of CO2 removal.

Multicriteria meta-heuristics for AGV dispatching control based on computational intelligence.

PubMed

Naso, David; Turchiano, Biagio

2005-04-01

In many manufacturing environments, automated guided vehicles are used to move the processed materials between various pickup and delivery points. The assignment of vehicles to unit loads is a complex problem that is often solved in real-time with simple dispatching rules. This paper proposes an automated guided vehicles dispatching approach based on computational intelligence. We adopt a fuzzy multicriteria decision strategy to simultaneously take into account multiple aspects in every dispatching decision. Since the typical short-term view of dispatching rules is one of the main limitations of such real-time assignment heuristics, we also incorporate in the multicriteria algorithm a specific heuristic rule that takes into account the empty-vehicle travel on a longer time-horizon. Moreover, we also adopt a genetic algorithm to tune the weights associated to each decision criteria in the global decision algorithm. The proposed approach is validated by means of a comparison with other dispatching rules, and with other recently proposed multicriteria dispatching strategies also based on computational Intelligence. The analysis of the results obtained by the proposed dispatching approach in both nominal and perturbed operating conditions (congestions, faults) confirms its effectiveness.

Active and Reactive Power Optimal Dispatch Associated with Load and DG Uncertainties in Active Distribution Network

NASA Astrophysics Data System (ADS)

Gao, F.; Song, X. H.; Zhang, Y.; Li, J. F.; Zhao, S. S.; Ma, W. Q.; Jia, Z. Y.

2017-05-01

In order to reduce the adverse effects of uncertainty on optimal dispatch in active distribution network, an optimal dispatch model based on chance-constrained programming is proposed in this paper. In this model, the active and reactive power of DG can be dispatched at the aim of reducing the operating cost. The effect of operation strategy on the cost can be reflected in the objective which contains the cost of network loss, DG curtailment, DG reactive power ancillary service, and power quality compensation. At the same time, the probabilistic constraints can reflect the operation risk degree. Then the optimal dispatch model is simplified as a series of single stage model which can avoid large variable dimension and improve the convergence speed. And the single stage model is solved using a combination of particle swarm optimization (PSO) and point estimate method (PEM). Finally, the proposed optimal dispatch model and method is verified by the IEEE33 test system.

Dispatch Control with PEV Charging and Renewables for Multiplayer Game Application

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

Davis, Nathan; Johnson, Brian; McJunkin, Timothy

This paper presents a demand response model for a hypothetical microgrid that integrates renewable resources and plug-in electric vehicle (PEV) charging systems. It is assumed that the microgrid has black start capability and that external generation is available for purchase while grid connected to satisfy additional demand. The microgrid is developed such that in addition to renewable, non-dispatchable generation from solar, wind and run of the river hydroelectric resources, local dispatchable generation is available in the form of small hydroelectric and moderately sized gas and coal fired facilities. To accurately model demand, the load model is separated into independent residential,more » commercial, industrial, and PEV charging systems. These are dispatched and committed based on a mixed integer linear program developed to minimize the cost of generation and load shedding while satisfying constraints associated with line limits, conservation of energy, and ramp rates of the generation units. The model extends a research tool to longer time frames intended for policy setting and educational environments and provides a realistic and intuitive understanding of beneficial and challenging aspects of electrification of vehicles combined with integration of green electricity production.« less

Development and implementation of a dynamic TES dispatch control component in a PV-CSP techno-economic performance modelling tool

NASA Astrophysics Data System (ADS)

Hansson, Linus; Guédez, Rafael; Larchet, Kevin; Laumert, Bjorn

2017-06-01

The dispatchability offered by thermal energy storage (TES) in concentrated solar power (CSP) and solar hybrid plants based on such technology presents the most important difference compared to power generation based only on photovoltaics (PV). This has also been one reason for recent hybridization efforts of the two technologies and the creation of Power Purchase Agreement (PPA) payment schemes based on offering higher payment multiples during daily hours of higher (peak or priority) demand. Recent studies involving plant-level thermal energy storage control strategies are however to a large extent based on pre-determined approaches, thereby not taking into account the actual dynamics of thermal energy storage system operation. In this study, the implementation of a dynamic dispatch strategy in the form of a TRNSYS controller for hybrid PV-CSP plants in the power-plant modelling tool DYESOPT is presented. In doing this it was attempted to gauge the benefits of incorporating a day-ahead approach to dispatch control compared to a fully pre-determined approach determining hourly dispatch only once prior to annual simulation. By implementing a dynamic strategy, it was found possible to enhance technical and economic performance for CSP-only plants designed for peaking operation and featuring low values of the solar multiple. This was achieved by enhancing dispatch control, primarily by taking storage levels at the beginning of every simulation day into account. The sequential prediction of the TES level could therefore be improved, notably for evaluated plants without integrated PV, for which the predicted storage levels deviated less than when PV was present in the design. While also featuring dispatch performance gains, optimal plant configurations for hybrid PV-CSP was found to present a trade-off in economic performance in the form of an increase in break-even electricity price when using the dynamic strategy which was offset to some extent by a reduction in upfront investment cost. An increase in turbine starts for the implemented strategy however highlights that this is where further improvements can be made.

Multi-Fluid Geothermal Energy Systems: Using CO2 for Dispatchable Renewable Power Generation and Grid Stabilization

NASA Astrophysics Data System (ADS)

Buscheck, T. A.; Bielicki, J. M.; Randolph, J.; Chen, M.; Hao, Y.; Sun, Y.

2013-12-01

Abstract We present an approach to use CO2 to (1) generate dispatchable renewable power that can quickly respond to grid fluctuations and be cost-competitive with natural gas, (2) stabilize the grid by efficiently storing large quantities of energy, (3) enable seasonal storage of solar thermal energy for grid integration, (4) produce brine for power-plant cooling, all which (5) increase CO2 value, rendering CO2 capture to be commerically viable, while (6) sequestering huge quantities of CO2. These attributes reduce carbon intensity of electric power, and enable cost-competitive, dispatchable power from major sources of renewable energy: wind, solar, and geothermal. Conventional geothermal power systems circulate brine as the working fluid to extract heat, but the parasitic power load for this circulation can consume a large portion of gross power output. Recently, CO2 has been considered as a working fluid because its advantageous properties reduce this parasitic loss. We expand on this idea by using multiple working fluids: brine, CO2, and N2. N2 can be separated from air at lower cost than captured CO2, it is not corrosive, and it will not react with the formation. N2 also can improve the economics of energy production and enable energy storage, while reducing operational risk. Extracting heat from geothermal reservoirs often requires submersible pumps to lift brine, but these pumps consume much of the generated electricity. In contrast, our approach drives fluid circulation by injecting supplemental, compressible fluids (CO2, and N2) with high coefficients of thermal expansion. These fluids augment reservoir pressure, produce artesian flow at the producers, and reduce the parasitic load. Pressure augmentation is improved by the thermosiphon effect that results from injecting cold/dense CO2 and N2. These fluids are heated to reservoir temperature, greatly expand, and increase the artesian flow of brine and supplemental fluid at the producers. Rather than using pumps, the thermosiphon directly converts reservoir thermal energy into mechanical energy for fluid circulation. Because stored pressure drives fluid production, the response time is faster than that of conventional geothermal power, already considered to be dispatchable. For conventional geothermal, the parasitic power load is in phase with gross power output. In contrast, our approach can time-shift much of the parasitic power load, which is dominated by the power required to separate N2 from air and compress it for injection. Because N2 is readily available, it can be injected intermittently. Thus, most of the parasitic power load can be shifted to coincide with minimum power demand or when there is a surplus of renewable power. Such a time-shift also allows net power output to be nearly equal to gross power output during peak demand. Energy storage can be almost 100 percent efficient because it is achieved by shifting the parasitic load, which is more efficient than other methods used to store energy and stabilize the grid. This work was performed under the auspices of the U.S. DOE by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Operation management of daily economic dispatch using novel hybrid particle swarm optimization and gravitational search algorithm with hybrid mutation strategy

NASA Astrophysics Data System (ADS)

Wang, Yan; Huang, Song; Ji, Zhicheng

2017-07-01

This paper presents a hybrid particle swarm optimization and gravitational search algorithm based on hybrid mutation strategy (HGSAPSO-M) to optimize economic dispatch (ED) including distributed generations (DGs) considering market-based energy pricing. A daily ED model was formulated and a hybrid mutation strategy was adopted in HGSAPSO-M. The hybrid mutation strategy includes two mutation operators, chaotic mutation, Gaussian mutation. The proposed algorithm was tested on IEEE-33 bus and results show that the approach is effective for this problem.

Optimized dispatch in a first-principles concentrating solar power production model

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

Wagner, Michael J.; Newman, Alexandra M.; Hamilton, William T.

Concentrating solar power towers, which include a steam-Rankine cycle with molten salt thermal energy storage, is an emerging technology whose maximum effectiveness relies on an optimal operational and dispatch policy. Given parameters such as start-up and shut-down penalties, expected electricity price profiles, solar availability, and system interoperability requirements, this paper seeks a profit-maximizing solution that determines start-up and shut-down times for the power cycle and solar receiver, and the times at which to dispatch stored and instantaneous quantities of energy over a 48-h horizon at hourly fidelity. The mixed-integer linear program (MIP) is subject to constraints including: (i) minimum andmore » maximum rates of start-up and shut-down, (ii) energy balance, including energetic state of the system as a whole and its components, (iii) logical rules governing the operational modes of the power cycle and solar receiver, and (iv) operational consistency between time periods. The novelty in this work lies in the successful integration of a dispatch optimization model into a detailed techno-economic analysis tool, specifically, the National Renewable Energy Laboratory's System Advisor Model (SAM). The MIP produces an optimized operating strategy, historically determined via a heuristic. Using several market electricity pricing profiles, we present comparative results for a system with and without dispatch optimization, indicating that dispatch optimization can improve plant profitability by 5-20% and thereby alter the economics of concentrating solar power technology. While we examine a molten salt power tower system, this analysis is equally applicable to the more mature concentrating solar parabolic trough system with thermal energy storage.« less

Technical assistance for law-enforcement communications: Case study report two

NASA Technical Reports Server (NTRS)

Reilly, N. B.; Mustain, J. A.

1979-01-01

Two case histories are presented. In one study the feasibility of consolidating dispatch center operations for small agencies is considered. System load measurements were taken and queueing analysis applied to determine numbers of personnel required for each separate agency and for a consolidated dispatch center. Functional requirements were developed and a cost model was designed to compare relative costs of various alternatives including continuation of the present system, consolidation of a manual system, and consolidated computer-aided dispatching. The second case history deals with the consideration of a multi-regional, intrastate radio frequency for improved interregional communications. Sample standards and specifications for radio equipment are provided.

Smart Grid | Climate Neutral Research Campuses | NREL

Science.gov Websites

begun to build smart grids. Most operate electricity grids that include power generation; load control plant managers use these communications for energy management and load shedding, which are among the top familiar with equipment interoperability, central dispatch, and load shedding. These are common in smart

Operational Impacts of Wind Energy Resources in the Bonneville Power Administration Control Area - Phase I Report

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

Makarov, Yuri V.; Lu, Shuai

2008-07-15

This report presents a methodology developed to study the future impact of wind on BPA power system load following and regulation requirements. The methodology uses historical data and stochastic processes to simulate the load balancing processes in the BPA power system, by mimicking the actual power system operations. Therefore, the results are close to reality, yet the study based on this methodology is convenient to conduct. Compared with the proposed methodology, existing methodologies for doing similar analysis include dispatch model simulation and standard deviation evaluation on load and wind data. Dispatch model simulation is constrained by the design of themore » dispatch program, and standard deviation evaluation is artificial in separating the load following and regulation requirements, both of which usually do not reflect actual operational practice. The methodology used in this study provides not only capacity requirement information, it also analyzes the ramp rate requirements for system load following and regulation processes. The ramp rate data can be used to evaluate generator response/maneuverability requirements, which is another necessary capability of the generation fleet for the smooth integration of wind energy. The study results are presented in an innovative way such that the increased generation capacity or ramp requirements are compared for two different years, across 24 hours a day. Therefore, the impact of different levels of wind energy on generation requirements at different times can be easily visualized.« less

Coordinated control of micro-grid based on distributed moving horizon control.

PubMed

Ma, Miaomiao; Shao, Liyang; Liu, Xiangjie

2018-05-01

This paper proposed the distributed moving horizon coordinated control scheme for the power balance and economic dispatch problems of micro-grid based on distributed generation. We design the power coordinated controller for each subsystem via moving horizon control by minimizing a suitable objective function. The objective function of distributed moving horizon coordinated controller is chosen based on the principle that wind power subsystem has the priority to generate electricity while photovoltaic power generation coordinates with wind power subsystem and the battery is only activated to meet the load demand when necessary. The simulation results illustrate that the proposed distributed moving horizon coordinated controller can allocate the output power of two generation subsystems reasonably under varying environment conditions, which not only can satisfy the load demand but also limit excessive fluctuations of output power to protect the power generation equipment. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

The impact of ancillary services in optimal DER investment decisions

DOE PAGES

Cardoso, Goncalo; Stadler, Michael; Mashayekh, Salman; ...

2017-04-25

Microgrid resource sizing problems typically include the analysis of a combination of value streams such as peak shaving, load shifting, or load scheduling, which support the economic feasibility of the microgrid deployment. However, microgrid benefits can go beyond these, and the ability to provide ancillary grid services such as frequency regulation or spinning and non-spinning reserves is well known, despite typically not being considered in resource sizing problems. This paper proposes the expansion of the Distributed Energy Resources Customer Adoption Model (DER-CAM), a state-of-the-art microgrid resource sizing model, to include revenue streams resulting from the participation in ancillary service markets.more » Results suggest that participation in such markets may not only influence the optimum resource sizing, but also the operational dispatch, with results being strongly influenced by the exact market requirements and clearing prices.« less

The impact of ancillary services in optimal DER investment decisions

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

Cardoso, Goncalo; Stadler, Michael; Mashayekh, Salman

Microgrid resource sizing problems typically include the analysis of a combination of value streams such as peak shaving, load shifting, or load scheduling, which support the economic feasibility of the microgrid deployment. However, microgrid benefits can go beyond these, and the ability to provide ancillary grid services such as frequency regulation or spinning and non-spinning reserves is well known, despite typically not being considered in resource sizing problems. This paper proposes the expansion of the Distributed Energy Resources Customer Adoption Model (DER-CAM), a state-of-the-art microgrid resource sizing model, to include revenue streams resulting from the participation in ancillary service markets.more » Results suggest that participation in such markets may not only influence the optimum resource sizing, but also the operational dispatch, with results being strongly influenced by the exact market requirements and clearing prices.« less

Improving the Military Household Goods Movement Program

DTIC Science & Technology

1989-06-01

They include the central franchise firms, local agencies, over-the-road vehicles and owner-operators [Ref. 37: p. 3-1]. However, the central franchise ...corporate logo may appear on the local agency and over-the-road vehicles. The central franchise firms are used for central dispatch and proper traffic...outbound and inbound moves which are normally dispatched and controlled :he central franchise firm. The last group. the owner-operators, will load, haul

Artificial neural network and SARIMA based models for power load forecasting in Turkish electricity market

PubMed Central

2017-01-01

Load information plays an important role in deregulated electricity markets, since it is the primary factor to make critical decisions on production planning, day-to-day operations, unit commitment and economic dispatch. Being able to predict the load for a short term, which covers one hour to a few days, equips power generation facilities and traders with an advantage. With the deregulation of electricity markets, a variety of short term load forecasting models are developed. Deregulation in Turkish Electricity Market has started in 2001 and liberalization is still in progress with rules being effective in its predefined schedule. However, there is a very limited number of studies for Turkish Market. In this study, we introduce two different models for current Turkish Market using Seasonal Autoregressive Integrated Moving Average (SARIMA) and Artificial Neural Network (ANN) and present their comparative performances. Building models that cope with the dynamic nature of deregulated market and are able to run in real-time is the main contribution of this study. We also use our ANN based model to evaluate the effect of several factors, which are claimed to have effect on electrical load. PMID:28426739

Artificial neural network and SARIMA based models for power load forecasting in Turkish electricity market.

PubMed

Bozkurt, Ömer Özgür; Biricik, Göksel; Tayşi, Ziya Cihan

2017-01-01

Load information plays an important role in deregulated electricity markets, since it is the primary factor to make critical decisions on production planning, day-to-day operations, unit commitment and economic dispatch. Being able to predict the load for a short term, which covers one hour to a few days, equips power generation facilities and traders with an advantage. With the deregulation of electricity markets, a variety of short term load forecasting models are developed. Deregulation in Turkish Electricity Market has started in 2001 and liberalization is still in progress with rules being effective in its predefined schedule. However, there is a very limited number of studies for Turkish Market. In this study, we introduce two different models for current Turkish Market using Seasonal Autoregressive Integrated Moving Average (SARIMA) and Artificial Neural Network (ANN) and present their comparative performances. Building models that cope with the dynamic nature of deregulated market and are able to run in real-time is the main contribution of this study. We also use our ANN based model to evaluate the effect of several factors, which are claimed to have effect on electrical load.

Metrics for Assessment of Smart Grid Data Integrity Attacks

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

Annarita Giani; Miles McQueen; Russell Bent

2012-07-01

There is an emerging consensus that the nation’s electricity grid is vulnerable to cyber attacks. This vulnerability arises from the increasing reliance on using remote measurements, transmitting them over legacy data networks to system operators who make critical decisions based on available data. Data integrity attacks are a class of cyber attacks that involve a compromise of information that is processed by the grid operator. This information can include meter readings of injected power at remote generators, power flows on transmission lines, and relay states. These data integrity attacks have consequences only when the system operator responds to compromised datamore » by redispatching generation under normal or contingency protocols. These consequences include (a) financial losses from sub-optimal economic dispatch to service loads, (b) robustness/resiliency losses from placing the grid at operating points that are at greater risk from contingencies, and (c) systemic losses resulting from cascading failures induced by poor operational choices. This paper is focused on understanding the connections between grid operational procedures and cyber attacks. We first offer two examples to illustrate how data integrity attacks can cause economic and physical damage by misleading operators into taking inappropriate decisions. We then focus on unobservable data integrity attacks involving power meter data. These are coordinated attacks where the compromised data are consistent with the physics of power flow, and are therefore passed by any bad data detection algorithm. We develop metrics to assess the economic impact of these attacks under re-dispatch decisions using optimal power flow methods. These metrics can be use to prioritize the adoption of appropriate countermeasures including PMU placement, encryption, hardware upgrades, and advance attack detection algorithms.« less

Novel methods for Solving Economic Dispatch of Security-Constrained Unit Commitment Based on Linear Programming

NASA Astrophysics Data System (ADS)

Guo, Sangang

2017-09-01

There are two stages in solving security-constrained unit commitment problems (SCUC) within Lagrangian framework: one is to obtain feasible units’ states (UC), the other is power economic dispatch (ED) for each unit. The accurate solution of ED is more important for enhancing the efficiency of the solution to SCUC for the fixed feasible units’ statues. Two novel methods named after Convex Combinatorial Coefficient Method and Power Increment Method respectively based on linear programming problem for solving ED are proposed by the piecewise linear approximation to the nonlinear convex fuel cost functions. Numerical testing results show that the methods are effective and efficient.

Symbiotic organisms search algorithm for dynamic economic dispatch with valve-point effects

NASA Astrophysics Data System (ADS)

Sonmez, Yusuf; Kahraman, H. Tolga; Dosoglu, M. Kenan; Guvenc, Ugur; Duman, Serhat

2017-05-01

In this study, symbiotic organisms search (SOS) algorithm is proposed to solve the dynamic economic dispatch with valve-point effects problem, which is one of the most important problems of the modern power system. Some practical constraints like valve-point effects, ramp rate limits and prohibited operating zones have been considered as solutions. Proposed algorithm was tested on five different test cases in 5 units, 10 units and 13 units systems. The obtained results have been compared with other well-known metaheuristic methods reported before. Results show that proposed algorithm has a good convergence and produces better results than other methods.

Study of Flexible Load Dispatch to Improve the Capacity of Wind Power Absorption

NASA Astrophysics Data System (ADS)

Yunlei, Yang; Shifeng, Zhang; Xiao, Chang; Da, Lei; Min, Zhang; Jinhao, Wang; Shengwen, Li; Huipeng, Li

2017-05-01

The dispatch method which track the trend of load demand by arranging the generation scheme of controllable hydro or thermal units faces great difficulties and challenges. With the increase of renewable energy sources such as wind power and photovoltaic power introduced to grid, system has to arrange much more spinning reserve units to compensate the unbalanced power. How to exploit the peak-shaving potential of flexible load which can be shifted with time or storage energy has become many scholars’ research direction. However, the modelling of different kinds of load and control strategy is considerably difficult, this paper choose the Air Conditioner with compressor which can storage energy in fact to study. The equivalent thermal parameters of Air Conditioner has been established. And with the use of “loop control” strategies, we can predict the regulated power of Air Conditioner. Then we established the Gen-Load optimal scheduling model including flexible load based on traditional optimal scheduling model. At last, an improved IEEE-30 case is used to verify. The result of simulation shows that flexible load can fast-track renewable power changes. More than that, with flexible load and reasonable incentive method to consumers, the operating cost of the system can be greatly cut down.

A new algorithm for real-time optimal dispatch of active and reactive power generation retaining nonlinearity

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

Roy, L.; Rao, N.D.

1983-04-01

This paper presents a new method for optimal dispatch of real and reactive power generation which is based on cartesian coordinate formulation of economic dispatch problem and reclassification of state and control variables associated with generator buses. The voltage and power at these buses are classified as parametric and functional inequality constraints, and are handled by reduced gradient technique and penalty factor approach respectively. The advantage of this classification is the reduction in the size of the equality constraint model, leading to less storage requirement. The rectangular coordinate formulation results in an exact equality constraint model in which the coefficientmore » matrix is real, sparse, diagonally dominant, smaller in size and need be computed and factorized once only in each gradient step. In addition, Lagragian multipliers are calculated using a new efficient procedure. A natural outcome of these features is the solution of the economic dispatch problem, faster than other methods available to date in the literature. Rapid and reliable convergence is an additional desirable characteristic of the method. Digital simulation results are presented on several IEEE test systems to illustrate the range of application of the method visa-vis the popular Dommel-Tinney (DT) procedure. It is found that the proposed method is more reliable, 3-4 times faster and requires 20-30 percent less storage compared to the DT algorithm, while being just as general. Thus, owing to its exactness, robust mathematical model and less computational requirements, the method developed in the paper is shown to be a practically feasible algorithm for on-line optimal power dispatch.« less

76 FR 72203 - Voltage Coordination on High Voltage Grids; Notice of Reliability Workshop Agenda

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-22

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. AD12-5-000] Voltage... currently coordinate the dispatch of reactive resources to support forecasted loads, generation and... reactive power needs of the distribution system or loads are coordinated or optimized. Panelists: Khaled...

Investigation on application of genetic algorithms to optimal reactive power dispatch of power systems

NASA Astrophysics Data System (ADS)

Wu, Q. H.; Ma, J. T.

1993-09-01

A primary investigation into application of genetic algorithms in optimal reactive power dispatch and voltage control is presented. The application was achieved, based on (the United Kingdom) National Grid 48 bus network model, using a novel genetic search approach. Simulation results, compared with that obtained using nonlinear programming methods, are included to show the potential of applications of the genetic search methodology in power system economical and secure operations.

Economic dispatch optimization for system integrating renewable energy sources

NASA Astrophysics Data System (ADS)

Jihane, Kartite; Mohamed, Cherkaoui

2018-05-01

Nowadays, the use of energy is growing especially in transportation and electricity industries. However this energy is based on conventional sources which pollute the environment. Multi-source system is seen as the best solution to sustainable development. This paper proposes the Economic Dispatch (ED) of hybrid renewable power system. The hybrid system is composed of ten thermal generators, photovoltaic (PV) generator and wind turbine generator. To show the importance of renewable energy sources (RES) in the energy mix we have ran the simulation for system integrated PV only and PV plus wind. The result shows that the system with renewable energy sources (RES) is more compromising than the system without RES in terms of fuel cost.

A Decomposition Method for Security Constrained Economic Dispatch of a Three-Layer Power System

NASA Astrophysics Data System (ADS)

Yang, Junfeng; Luo, Zhiqiang; Dong, Cheng; Lai, Xiaowen; Wang, Yang

2018-01-01

This paper proposes a new decomposition method for the security-constrained economic dispatch in a three-layer large-scale power system. The decomposition is realized using two main techniques. The first is to use Ward equivalencing-based network reduction to reduce the number of variables and constraints in the high-layer model without sacrificing accuracy. The second is to develop a price response function to exchange signal information between neighboring layers, which significantly improves the information exchange efficiency of each iteration and results in less iterations and less computational time. The case studies based on the duplicated RTS-79 system demonstrate the effectiveness and robustness of the proposed method.

Optimization Scheduling Model for Wind-thermal Power System Considering the Dynamic penalty factor

NASA Astrophysics Data System (ADS)

PENG, Siyu; LUO, Jianchun; WANG, Yunyu; YANG, Jun; RAN, Hong; PENG, Xiaodong; HUANG, Ming; LIU, Wanyu

2018-03-01

In this paper, a new dynamic economic dispatch model for power system is presented.Objective function of the proposed model presents a major novelty in the dynamic economic dispatch including wind farm: introduced the “Dynamic penalty factor”, This factor could be computed by using fuzzy logic considering both the variable nature of active wind power and power demand, and it could change the wind curtailment cost according to the different state of the power system. Case studies were carried out on the IEEE30 system. Results show that the proposed optimization model could mitigate the wind curtailment and the total cost effectively, demonstrate the validity and effectiveness of the proposed model.

A Modified Artificial Bee Colony Algorithm Application for Economic Environmental Dispatch

NASA Astrophysics Data System (ADS)

Tarafdar Hagh, M.; Baghban Orandi, Omid

2018-03-01

In conventional fossil-fuel power systems, the economic environmental dispatch (EED) problem is a major problem that optimally determines the output power of generating units in a way that cost of total production and emission level be minimized simultaneously, and at the same time all the constraints of units and system are satisfied properly. To solve EED problem which is a non-convex optimization problem, a modified artificial bee colony (MABC) algorithm is proposed in this paper. This algorithm by implementing weighted sum method is applied on two test systems, and eventually, obtained results are compared with other reported results. Comparison of results confirms superiority and efficiency of proposed method clearly.

Adaptive grid based multi-objective Cauchy differential evolution for stochastic dynamic economic emission dispatch with wind power uncertainty

PubMed Central

Lei, Xiaohui; Wang, Chao; Yue, Dong; Xie, Xiangpeng

2017-01-01

Since wind power is integrated into the thermal power operation system, dynamic economic emission dispatch (DEED) has become a new challenge due to its uncertain characteristics. This paper proposes an adaptive grid based multi-objective Cauchy differential evolution (AGB-MOCDE) for solving stochastic DEED with wind power uncertainty. To properly deal with wind power uncertainty, some scenarios are generated to simulate those possible situations by dividing the uncertainty domain into different intervals, the probability of each interval can be calculated using the cumulative distribution function, and a stochastic DEED model can be formulated under different scenarios. For enhancing the optimization efficiency, Cauchy mutation operation is utilized to improve differential evolution by adjusting the population diversity during the population evolution process, and an adaptive grid is constructed for retaining diversity distribution of Pareto front. With consideration of large number of generated scenarios, the reduction mechanism is carried out to decrease the scenarios number with covariance relationships, which can greatly decrease the computational complexity. Moreover, the constraint-handling technique is also utilized to deal with the system load balance while considering transmission loss among thermal units and wind farms, all the constraint limits can be satisfied under the permitted accuracy. After the proposed method is simulated on three test systems, the obtained results reveal that in comparison with other alternatives, the proposed AGB-MOCDE can optimize the DEED problem while handling all constraint limits, and the optimal scheme of stochastic DEED can decrease the conservation of interval optimization, which can provide a more valuable optimal scheme for real-world applications. PMID:28961262

A Method for Optimal Load Dispatch of a Multi-zone Power System with Zonal Exchange Constraints

NASA Astrophysics Data System (ADS)

Hazarika, Durlav; Das, Ranjay

2018-04-01

This paper presented a method for economic generation scheduling of a multi-zone power system having inter zonal operational constraints. For this purpose, the generator rescheduling for a multi area power system having inter zonal operational constraints has been represented as a two step optimal generation scheduling problem. At first, the optimal generation scheduling has been carried out for the zone having surplus or deficient generation with proper spinning reserve using co-ordination equation. The power exchange required for the deficit zones and zones having no generation are estimated based on load demand and generation for the zone. The incremental transmission loss formulas for the transmission lines participating in the power transfer process among the zones are formulated. Using these, incremental transmission loss expression in co-ordination equation, the optimal generation scheduling for the zonal exchange has been determined. Simulation is carried out on IEEE 118 bus test system to examine the applicability and validity of the method.

Hybrid solar converters for maximum exergy and inexpensive dispatchable electricity

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

Branz, Howard M.; Regan, William; Gerst, Kacy J.

Photovoltaic (PV) solar energy systems are being deployed at an accelerating rate to supply low-carbon electricity worldwide. However, PV is unlikely to economically supply much more than 10% of the world's electricity unless there is a dramatic reduction in the cost of electricity storage. There is an important scientific and technological opportunity to address the storage challenge by developing inexpensive hybrid solar converters that collect solar heat at temperatures between about 200 and 600 °C and also incorporate PV. Since heat can be stored and converted to electricity at relatively low cost, collection of high exergy content (high temperature) solarmore » heat can provide energy that is dispatchable on demand to meet loads that are not well matched to solar insolation. However, PV cells can collect and convert much of the solar spectrum to electricity more efficiently and inexpensively than solar thermal systems. Advances in spectrum-splitting optics, high-temperature PV cells, thermal management and system design are needed for transformational hybrid converters. We propose that maximizing the exergy output from the solar converters while minimizing the cost of exergy can help propel solar energy toward a higher contribution to carbon-free electricity in the long term than the prevailing paradigm of maximizing the energy output while minimizing the cost of energy« less

Coordinated Scheduling for Interdependent Electric Power and Natural Gas Infrastructures

DOE PAGES

Zlotnik, Anatoly; Roald, Line; Backhaus, Scott; ...

2016-03-24

The extensive installation of gas-fired power plants in many parts of the world has led electric systems to depend heavily on reliable gas supplies. The use of gas-fired generators for peak load and reserve provision causes high intraday variability in withdrawals from high-pressure gas transmission systems. Such variability can lead to gas price fluctuations and supply disruptions that affect electric generator dispatch, electricity prices, and threaten the security of power systems and gas pipelines. These infrastructures function on vastly different spatio-temporal scales, which prevents current practices for separate operations and market clearing from being coordinated. Here in this article, wemore » apply new techniques for control of dynamic gas flows on pipeline networks to examine day-ahead scheduling of electric generator dispatch and gas compressor operation for different levels of integration, spanning from separate forecasting, and simulation to combined optimal control. We formulate multiple coordination scenarios and develop tractable physically accurate computational implementations. These scenarios are compared using an integrated model of test networks for power and gas systems with 24 nodes and 24 pipes, respectively, which are coupled through gas-fired generators. The analysis quantifies the economic efficiency and security benefits of gas-electric coordination and dynamic gas system operation.« less

Dynamic Energy Management System for a Smart Microgrid.

PubMed

Venayagamoorthy, Ganesh Kumar; Sharma, Ratnesh K; Gautam, Prajwal K; Ahmadi, Afshin

2016-08-01

This paper presents the development of an intelligent dynamic energy management system (I-DEMS) for a smart microgrid. An evolutionary adaptive dynamic programming and reinforcement learning framework is introduced for evolving the I-DEMS online. The I-DEMS is an optimal or near-optimal DEMS capable of performing grid-connected and islanded microgrid operations. The primary sources of energy are sustainable, green, and environmentally friendly renewable energy systems (RESs), e.g., wind and solar; however, these forms of energy are uncertain and nondispatchable. Backup battery energy storage and thermal generation were used to overcome these challenges. Using the I-DEMS to schedule dispatches allowed the RESs and energy storage devices to be utilized to their maximum in order to supply the critical load at all times. Based on the microgrid's system states, the I-DEMS generates energy dispatch control signals, while a forward-looking network evaluates the dispatched control signals over time. Typical results are presented for varying generation and load profiles, and the performance of I-DEMS is compared with that of a decision tree approach-based DEMS (D-DEMS). The robust performance of the I-DEMS was illustrated by examining microgrid operations under different battery energy storage conditions.

A Distributed Algorithm for Economic Dispatch Over Time-Varying Directed Networks With Delays

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

Yang, Tao; Lu, Jie; Wu, Di

In power system operation, economic dispatch problem (EDP) is designed to minimize the total generation cost while meeting the demand and satisfying generator capacity limits. This paper proposes an algorithm based on the gradient-push method to solve the EDP in a distributed manner over communication networks potentially with time-varying topologies and communication delays. It has been shown that the proposed method is guaranteed to solve the EDP if the time-varying directed communication network is uniformly jointly strongly connected. Moreover, the proposed algorithm is also able to handle arbitrarily large but bounded time delays on communication links. Numerical simulations are usedmore » to illustrate and validate the proposed algorithm.« less

Optimization of joint energy micro-grid with cold storage

NASA Astrophysics Data System (ADS)

Xu, Bin; Luo, Simin; Tian, Yan; Chen, Xianda; Xiong, Botao; Zhou, Bowen

2018-02-01

To accommodate distributed photovoltaic (PV) curtailment, to make full use of the joint energy micro-grid with cold storage, and to reduce the high operating costs, the economic dispatch of joint energy micro-grid load is particularly important. Considering the different prices during the peak and valley durations, an optimization model is established, which takes the minimum production costs and PV curtailment fluctuations as the objectives. Linear weighted sum method and genetic-taboo Particle Swarm Optimization (PSO) algorithm are used to solve the optimization model, to obtain optimal power supply output. Taking the garlic market in Henan as an example, the simulation results show that considering distributed PV and different prices in different time durations, the optimization strategies are able to reduce the operating costs and accommodate PV power efficiently.

Short-term load forecasting of power system

NASA Astrophysics Data System (ADS)

Xu, Xiaobin

2017-05-01

In order to ensure the scientific nature of optimization about power system, it is necessary to improve the load forecasting accuracy. Power system load forecasting is based on accurate statistical data and survey data, starting from the history and current situation of electricity consumption, with a scientific method to predict the future development trend of power load and change the law of science. Short-term load forecasting is the basis of power system operation and analysis, which is of great significance to unit combination, economic dispatch and safety check. Therefore, the load forecasting of the power system is explained in detail in this paper. First, we use the data from 2012 to 2014 to establish the partial least squares model to regression analysis the relationship between daily maximum load, daily minimum load, daily average load and each meteorological factor, and select the highest peak by observing the regression coefficient histogram Day maximum temperature, daily minimum temperature and daily average temperature as the meteorological factors to improve the accuracy of load forecasting indicators. Secondly, in the case of uncertain climate impact, we use the time series model to predict the load data for 2015, respectively, the 2009-2014 load data were sorted out, through the previous six years of the data to forecast the data for this time in 2015. The criterion for the accuracy of the prediction is the average of the standard deviations for the prediction results and average load for the previous six years. Finally, considering the climate effect, we use the BP neural network model to predict the data in 2015, and optimize the forecast results on the basis of the time series model.

An Approach to Economic Dispatch with Multiple Fuels Based on Particle Swarm Optimization

NASA Astrophysics Data System (ADS)

Sriyanyong, Pichet

2011-06-01

Particle Swarm Optimization (PSO), a stochastic optimization technique, shows superiority to other evolutionary computation techniques in terms of less computation time, easy implementation with high quality solution, stable convergence characteristic and independent from initialization. For this reason, this paper proposes the application of PSO to the Economic Dispatch (ED) problem, which occurs in the operational planning of power systems. In this study, ED problem can be categorized according to the different characteristics of its cost function that are ED problem with smooth cost function and ED problem with multiple fuels. Taking the multiple fuels into account will make the problem more realistic. The experimental results show that the proposed PSO algorithm is more efficient than previous approaches under consideration as well as highly promising in real world applications.

18. VIEW OF ANCHOR BRIDGE NUMBER 310 LOOKING WEST ALONG ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

18. VIEW OF ANCHOR BRIDGE NUMBER 310 LOOKING WEST ALONG THE MAIN TRACK LOCATED TO THE NORTH OF THE COS COB POWER PLANT. THE LOAD DISPATCHER'S TOWER IS SHOWN IN THE LEFT FOREGROUND. AT THIS STATION THE DISPATCHER CONTROLLED POWER OUTPUT TO VARIOUS PARTS OF THE SYSTEM. THE STRUCTURE SERVES THE SAME PURPOSE IN 1993 AND CAN BE OPERATED LOCALLY OR REMOTELY FROM METRO-NORTH'S HEADQUARTERS IN MANHATTAN. THE STEEL STRUCTURE AND STACK IN THE BACKGROUND ARE PART OF THE BOILER 902-903 INSTALLATION. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

The state of energy storage in electric utility systems and its effect on renewable energy resources

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

Rau, N S

1994-08-01

This report describes the state of the art of electric energy storage technologies and discusses how adding intermittent renewable energy technologies (IRETs) to a utility network affects the benefits from storage dispatch. Load leveling was the mode of storage dispatch examined in the study. However, the report recommended that other modes be examined in the future for kilowatt and kilowatt-hour optimization of storage. The motivation to install storage with IRET generation can arise from two considerations: reliability and enhancement of the value of energy. Because adding storage increases cost, reliability-related storage is attractive only if the accruing benefits exceed themore » cost of storage installation. The study revealed that the operation of storage should not be guided by the output of the IRET but rather by system marginal costs. Consequently, in planning studies to quantify benefits, storage should not be considered as an entity belonging to the system and not as a component of IRETS. The study also indicted that because the infusion of IRET energy tends to reduce system marginal cost, the benefits from load leveling (value of energy) would be reduced. However, if a system has storage, particularly if the storage is underutilized, its dispatch can be reoriented to enhance the benefits of IRET integration.« less

A Multiobjective Interval Programming Model for Wind-Hydrothermal Power System Dispatching Using 2-Step Optimization Algorithm

PubMed Central

Jihong, Qu

2014-01-01

Wind-hydrothermal power system dispatching has received intensive attention in recent years because it can help develop various reasonable plans to schedule the power generation efficiency. But future data such as wind power output and power load would not be accurately predicted and the nonlinear nature involved in the complex multiobjective scheduling model; therefore, to achieve accurate solution to such complex problem is a very difficult task. This paper presents an interval programming model with 2-step optimization algorithm to solve multiobjective dispatching. Initially, we represented the future data into interval numbers and simplified the object function to a linear programming problem to search the feasible and preliminary solutions to construct the Pareto set. Then the simulated annealing method was used to search the optimal solution of initial model. Thorough experimental results suggest that the proposed method performed reasonably well in terms of both operating efficiency and precision. PMID:24895663

A multiobjective interval programming model for wind-hydrothermal power system dispatching using 2-step optimization algorithm.

PubMed

Ren, Kun; Jihong, Qu

2014-01-01

Wind-hydrothermal power system dispatching has received intensive attention in recent years because it can help develop various reasonable plans to schedule the power generation efficiency. But future data such as wind power output and power load would not be accurately predicted and the nonlinear nature involved in the complex multiobjective scheduling model; therefore, to achieve accurate solution to such complex problem is a very difficult task. This paper presents an interval programming model with 2-step optimization algorithm to solve multiobjective dispatching. Initially, we represented the future data into interval numbers and simplified the object function to a linear programming problem to search the feasible and preliminary solutions to construct the Pareto set. Then the simulated annealing method was used to search the optimal solution of initial model. Thorough experimental results suggest that the proposed method performed reasonably well in terms of both operating efficiency and precision.

Alleviating line overload by line switching

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

Brown, H.E.

1988-01-01

Traditionally, the method used by power system dispatchers to reduce or to eliminate line overload conditions has been to shift generation. Such shifts are generally in conflict with the carefully considered economic dispatch of generation. A proper generation schedule has taken into account many factors, such as generator limits, transmission penalties, incremental costs, var support, and system security. Any deviation from this schedule results in increased production cost. Recently, consideration has been given to alleviating line overloads by line switching. In many situations, line switching does not greatly change the transmission penalty factors and, therefore, can be undertaken without seriouslymore » affecting the economic dispatch. It would be convenient for system operators to have a fast, easy-to-operate computer and program available for the evaluation of the efficacy of a line removal (or addition) in dealing with an overload. It is imperative that the operator be properly advised, that a certain line switching reduces the overload and not aggravate the condition. After it has been determined that a line opening (or closing) produces the desired effect, the operator still must assess the consequence of such switching on system security before actually taking such action.« less

Short-term benefits from central unit commitment and dispatch: Application to the Southern African Power Pool

NASA Astrophysics Data System (ADS)

Bowen, Brian Hugh

1998-12-01

Electricity utilities in the Southern African region are conscious that gains could be made from more economically efficient trading but have had no tools with which to analyze the effects of a change in policy. This research is the first to provide transparent quantitative techniques to quantify the impacts of new trading arrangements in this region. The study poses a model of the recently formed Southern African Power Pool, built with the collaboration of the region's national utilities to represent each country's demand and generation/transmission system. The multi-region model includes commitment and dispatch from diverse hydrothermal sources over a vast area. Economic gains are determined by comparing the total costs under free-trade conditions with those from the existing fixed-trade bilateral arrangements. The objective function minimizes production costs needed to meet total demand, subject to each utility's constraints for thermal and hydro generation, transmission, load balance and losses. Linearized thermal cost functions are used along with linearized input output hydropower plant curves and hydrothermal on/off status variables to formulate a mixed-integer programming problem. Results from the modeling show that moving to optimal trading patterns could save between 70 million and 130 million per year. With free-trade policies the quantity of power flow between utilities is doubled and maximum usage is made of the hydropower stations thus reducing costs and fuel use. In electricity exporting countries such as Zambia and Mozambique gains from increased trade are achieved which equal 16% and 18% respectively of the value of their total manufactured exports. A sensitivity analysis is conducted on the possible effects of derating generation, derating transmission and reducing water inflows but gains remain large. Maximum economic gains from optimal trading patterns can be achieved by each country allowing centralized control through the newly founded SAPP coordination center. Using standard mixed integer programming solvers makes the cost of such modeling activity easily affordable to each utility in the Southern African pool. This research provides the utilities with the modeling tools to quantify the gains from increased trade and thereby furthers a move towards greater efficiency, faster economic growth and reduced use of fossil fuels.

Analyzing the Effect of Multi-fuel and Practical Constraints on Realistic Economic Load Dispatch using Novel Two-stage PSO

NASA Astrophysics Data System (ADS)

Chintalapudi, V. S.; Sirigiri, Sivanagaraju

2017-04-01

In power system restructuring, pricing the electrical power plays a vital role in cost allocation between suppliers and consumers. In optimal power dispatch problem, not only the cost of active power generation but also the costs of reactive power generated by the generators should be considered to increase the effectiveness of the problem. As the characteristics of reactive power cost curve are similar to that of active power cost curve, a nonconvex reactive power cost function is formulated. In this paper, a more realistic multi-fuel total cost objective is formulated by considering active and reactive power costs of generators. The formulated cost function is optimized by satisfying equality, in-equality and practical constraints using the proposed uniform distributed two-stage particle swarm optimization. The proposed algorithm is a combination of uniform distribution of control variables (to start the iterative process with good initial value) and two-stage initialization processes (to obtain best final value in less number of iterations) can enhance the effectiveness of convergence characteristics. Obtained results for the considered standard test functions and electrical systems indicate the effectiveness of the proposed algorithm and can obtain efficient solution when compared to existing methods. Hence, the proposed method is a promising method and can be easily applied to optimize the power system objectives.

Wind Energy Management System EMS Integration Project: Incorporating Wind Generation and Load Forecast Uncertainties into Power Grid Operations

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

Makarov, Yuri V.; Huang, Zhenyu; Etingov, Pavel V.

2010-01-01

The power system balancing process, which includes the scheduling, real time dispatch (load following) and regulation processes, is traditionally based on deterministic models. Since the conventional generation needs time to be committed and dispatched to a desired megawatt level, the scheduling and load following processes use load and wind and solar power production forecasts to achieve future balance between the conventional generation and energy storage on the one side, and system load, intermittent resources (such as wind and solar generation), and scheduled interchange on the other side. Although in real life the forecasting procedures imply some uncertainty around the loadmore » and wind/solar forecasts (caused by forecast errors), only their mean values are actually used in the generation dispatch and commitment procedures. Since the actual load and intermittent generation can deviate from their forecasts, it becomes increasingly unclear (especially, with the increasing penetration of renewable resources) whether the system would be actually able to meet the conventional generation requirements within the look-ahead horizon, what the additional balancing efforts would be needed as we get closer to the real time, and what additional costs would be incurred by those needs. To improve the system control performance characteristics, maintain system reliability, and minimize expenses related to the system balancing functions, it becomes necessary to incorporate the predicted uncertainty ranges into the scheduling, load following, and, in some extent, into the regulation processes. It is also important to address the uncertainty problem comprehensively by including all sources of uncertainty (load, intermittent generation, generators’ forced outages, etc.) into consideration. All aspects of uncertainty such as the imbalance size (which is the same as capacity needed to mitigate the imbalance) and generation ramping requirement must be taken into account. The latter unique features make this work a significant step forward toward the objective of incorporating of wind, solar, load, and other uncertainties into power system operations. Currently, uncertainties associated with wind and load forecasts, as well as uncertainties associated with random generator outages and unexpected disconnection of supply lines, are not taken into account in power grid operation. Thus, operators have little means to weigh the likelihood and magnitude of upcoming events of power imbalance. In this project, funded by the U.S. Department of Energy (DOE), a framework has been developed for incorporating uncertainties associated with wind and load forecast errors, unpredicted ramps, and forced generation disconnections into the energy management system (EMS) as well as generation dispatch and commitment applications. A new approach to evaluate the uncertainty ranges for the required generation performance envelope including balancing capacity, ramping capability, and ramp duration has been proposed. The approach includes three stages: forecast and actual data acquisition, statistical analysis of retrospective information, and prediction of future grid balancing requirements for specified time horizons and confidence levels. Assessment of the capacity and ramping requirements is performed using a specially developed probabilistic algorithm based on a histogram analysis, incorporating all sources of uncertainties of both continuous (wind and load forecast errors) and discrete (forced generator outages and start-up failures) nature. A new method called the “flying brick” technique has been developed to evaluate the look-ahead required generation performance envelope for the worst case scenario within a user-specified confidence level. A self-validation algorithm has been developed to validate the accuracy of the confidence intervals.« less

A tutorial description of an interior point method and its applications to security-constrained economic dispatch

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

Vargas, L.S.; Quintana, V.H.; Vannelli, A.

This paper deals with the use of Successive Linear Programming (SLP) for the solution of the Security-Constrained Economic Dispatch (SCED) problem. The authors tutorially describe an Interior Point Method (IPM) for the solution of Linear Programming (LP) problems, discussing important implementation issues that really make this method far superior to the simplex method. A study of the convergence of the SLP technique and a practical criterion to avoid oscillatory behavior in the iteration process are also proposed. A comparison of the proposed method with an efficient simplex code (MINOS) is carried out by solving SCED problems on two standard IEEEmore » systems. The results show that the interior point technique is reliable, accurate and more than two times faster than the simplex algorithm.« less

Intelligent power consumption with two-way shift able feature and its implementation

NASA Astrophysics Data System (ADS)

Xu, Jing; Liu, Youwei

2017-10-01

This paper proposes an intelligent power consumption system with two-way shift able feature and its implementation. Based on power consumption information of standby load and load in working state, a dispatching system decomposes load regulation demand top-down to smart appliances and makes them response orderly as required. It designs a code-based representation method for power consumption information and takes account of standby load, which lays the information foundation for load increment. It also presents a shift able index, which can be used to comprehensively reflect feature of electrical equipment and users and provides a basis for load priority.

Distributed Optimal Consensus Over Resource Allocation Network and Its Application to Dynamical Economic Dispatch.

PubMed

Li, Chaojie; Yu, Xinghuo; Huang, Tingwen; He, Xing; Chaojie Li; Xinghuo Yu; Tingwen Huang; Xing He; Li, Chaojie; Huang, Tingwen; He, Xing; Yu, Xinghuo

2018-06-01

The resource allocation problem is studied and reformulated by a distributed interior point method via a -logarithmic barrier. By the facilitation of the graph Laplacian, a fully distributed continuous-time multiagent system is developed for solving the problem. Specifically, to avoid high singularity of the -logarithmic barrier at boundary, an adaptive parameter switching strategy is introduced into this dynamical multiagent system. The convergence rate of the distributed algorithm is obtained. Moreover, a novel distributed primal-dual dynamical multiagent system is designed in a smart grid scenario to seek the saddle point of dynamical economic dispatch, which coincides with the optimal solution. The dual decomposition technique is applied to transform the optimization problem into easily solvable resource allocation subproblems with local inequality constraints. The good performance of the new dynamical systems is, respectively, verified by a numerical example and the IEEE six-bus test system-based simulations.

Assessing CO2 Mitigation Options Utilizing Detailed Electricity Characteristics and Including Renewable Generation

NASA Astrophysics Data System (ADS)

Bensaida, K.; Alie, Colin; Elkamel, A.; Almansoori, A.

2017-08-01

This paper presents a novel techno-economic optimization model for assessing the effectiveness of CO2 mitigation options for the electricity generation sub-sector that includes renewable energy generation. The optimization problem was formulated as a MINLP model using the GAMS modeling system. The model seeks the minimization of the power generation costs under CO2 emission constraints by dispatching power from low CO2 emission-intensity units. The model considers the detailed operation of the electricity system to effectively assess the performance of GHG mitigation strategies and integrates load balancing, carbon capture and carbon taxes as methods for reducing CO2 emissions. Two case studies are discussed to analyze the benefits and challenges of the CO2 reduction methods in the electricity system. The proposed mitigations options would not only benefit the environment, but they will as well improve the marginal cost of producing energy which represents an advantage for stakeholders.

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

Krishnamurthy, Dheepak

This paper is an overview of Power System Simulation Toolbox (psst). psst is an open-source Python application for the simulation and analysis of power system models. psst simulates the wholesale market operation by solving a DC Optimal Power Flow (DCOPF), Security Constrained Unit Commitment (SCUC) and a Security Constrained Economic Dispatch (SCED). psst also includes models for the various entities in a power system such as Generator Companies (GenCos), Load Serving Entities (LSEs) and an Independent System Operator (ISO). psst features an open modular object oriented architecture that will make it useful for researchers to customize, expand, experiment beyond solvingmore » traditional problems. psst also includes a web based Graphical User Interface (GUI) that allows for user friendly interaction and for implementation on remote High Performance Computing (HPCs) clusters for parallelized operations. This paper also provides an illustrative application of psst and benchmarks with standard IEEE test cases to show the advanced features and the performance of toolbox.« less

Closeup view of a general electric company demand meter which ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Close-up view of a general electric company demand meter which formerly monitored railroad power usage obtained from Philadelphia Electric Company sources. - Thirtieth Street Station, Load Dispatch Center, Thirtieth & Market Streets, Railroad Station, Amtrak (formerly Pennsylvania Railroad Station), Philadelphia, Philadelphia County, PA

Scheduling revisited workstations in integrated-circuit fabrication

NASA Technical Reports Server (NTRS)

Kline, Paul J.

1992-01-01

The cost of building new semiconductor wafer fabrication factories has grown rapidly, and a state-of-the-art fab may cost 250 million dollars or more. Obtaining an acceptable return on this investment requires high productivity from the fabrication facilities. This paper describes the Photo Dispatcher system which was developed to make machine-loading recommendations on a set of key fab machines. Dispatching policies that generally perform well in job shops (e.g., Shortest Remaining Processing Time) perform poorly for workstations such as photolithography which are visited several times by the same lot of silicon wafers. The Photo Dispatcher evaluates the history of workloads throughout the fab and identifies bottleneck areas. The scheduler then assigns priorities to lots depending on where they are headed after photolithography. These priorities are designed to avoid starving bottleneck workstations and to give preference to lots that are headed to areas where they can be processed with minimal waiting. Other factors considered by the scheduler to establish priorities are the nearness of a lot to the end of its process flow and the time that the lot has already been waiting in queue. Simulations that model the equipment and products in one of Texas Instrument's wafer fabs show the Photo Dispatcher can produce a 10 percent improvement in the time required to fabricate integrated circuits.

Research on wind power grid-connected operation and dispatching strategies of Liaoning power grid

NASA Astrophysics Data System (ADS)

Han, Qiu; Qu, Zhi; Zhou, Zhi; He, Xiaoyang; Li, Tie; Jin, Xiaoming; Li, Jinze; Ling, Zhaowei

2018-02-01

As a kind of clean energy, wind power has gained rapid development in recent years. Liaoning Province has abundant wind resources and the total installed capacity of wind power is in the forefront. With the large-scale wind power grid-connected operation, the contradiction between wind power utilization and peak load regulation of power grid has been more prominent. To this point, starting with the power structure and power grid installation situation of Liaoning power grid, the distribution and the space-time output characteristics of wind farm, the prediction accuracy, the curtailment and the off-grid situation of wind power are analyzed. Based on the deep analysis of the seasonal characteristics of power network load, the composition and distribution of main load are presented. Aiming at the problem between the acceptance of wind power and power grid adjustment, the scheduling strategies are given, including unit maintenance scheduling, spinning reserve, energy storage equipment settings by the analysis of the operation characteristics and the response time of thermal power units and hydroelectric units, which can meet the demand of wind power acceptance and provide a solution to improve the level of power grid dispatching.

Using Conventional Hydropower to Help Alleviate Variable Resource Grid Integration Challenges in the Western U.S

NASA Astrophysics Data System (ADS)

Veselka, T. D.; Poch, L.

2011-12-01

Integrating high penetration levels of wind and solar energy resources into the power grid is a formidable challenge in virtually all interconnected systems due to the fact that supply and demand must remain in balance at all times. Since large scale electricity storage is currently not economically viable, generation must exactly match electricity demand plus energy losses in the system as time unfolds. Therefore, as generation from variable resources such as wind and solar fluctuate, production from generating resources that are easier to control and dispatch need to compensate for these fluctuations while at the same time respond to both instantaneous change in load and follow daily load profiles. The grid in the Western U.S. is not exempt to grid integration challenges associated with variable resources. However, one advantage that the power system in the Western U.S. has over many other regional power systems is that its footprint contains an abundance of hydropower resources. Hydropower plants, especially those that have reservoir water storage, can physically change electricity production levels very quickly both via a dispatcher and through automatic generation control. Since hydropower response time is typically much faster than other dispatchable resources such as steam or gas turbines, it is well suited to alleviate variable resource grid integration issues. However, despite an abundance of hydropower resources and the current low penetration of variable resources in the Western U.S., problems have already surfaced. This spring in the Pacific Northwest, wetter than normal hydropower conditions in combination with transmission constraints resulted in controversial wind resource shedding. This action was taken since water spilling would have increased dissolved oxygen levels downstream of dams thereby significantly degrading fish habitats. The extent to which hydropower resources will be able to contribute toward a stable and reliable Western grid is currently being studied. Typically these studies consider the inherent flexibility of hydropower technologies, but tend to fall short on details regarding grid operations, institutional arrangements, and hydropower environmental regulations. This presentation will focus on an analysis that Argonne National Laboratory is conducting in collaboration with the Western Area Power Administration (Western). The analysis evaluates the extent to which Western's hydropower resources may help with grid integration challenges via a proposed Energy Imbalance Market. This market encompasses most of the Western Electricity Coordinating Council footprint. It changes grid operations such that the real-time dispatch would be, in part, based on a 5-minute electricity market. The analysis includes many factors such as site-specific environmental considerations at each of its hydropower facilities, long-term firm purchase agreements, and hydropower operating objectives and goals. Results of the analysis indicate that site-specific details significantly affect the ability of hydropower plant to respond to grid needs in a future which will have a high penetration of variable resources.

Engineering Sedimentary Geothermal Resources for Large-Scale Dispatchable Renewable Electricity

NASA Astrophysics Data System (ADS)

Bielicki, Jeffrey; Buscheck, Thomas; Chen, Mingjie; Sun, Yunwei; Hao, Yue; Saar, Martin; Randolph, Jimmy

2014-05-01

Mitigating climate change requires substantial penetration of renewable energy and economically viable options for CO2 capture and storage (CCS). We present an approach using CO2 and N2 in sedimentary basin geothermal resources that (1) generates baseload and dispatchable power, (2) efficiently stores large amounts of energy, and (3) enables seasonal storage of solar energy, all which (5) increase the value of CO2 and render CCS commercially viable. Unlike the variability of solar and wind resources, geothermal heat is a constant source of renewable energy. Using CO2 as a supplemental geothermal working fluid, in addition to brine, reduces the parasitic load necessary to recirculate fluids. Adding N2 is beneficial because it is cheaper, will not react with materials and subsurface formations, and enables bulk energy storage. The high coefficients of thermal expansion of CO2 and N2 (a) augment reservoir pressure, (b) generate artesian flow at the production wells, and (c) produce self-convecting thermosiphons that directly convert reservoir heat to mechanical energy for fluid recirculation. Stored pressure drives fluid production and responds faster than conventional brine-based geothermal systems. Our design uses concentric rings of horizontal wells to create a hydraulic divide that stores supplemental fluids and pressure. Production and injection wells are controlled to schedule power delivery and time-shift the parasitic power necessary to separate N2 from air and compress it for injection. The parasitic load can be scheduled during minimum power demand or when there is excess electricity from wind or solar. Net power output can nearly equal gross power output during peak demand, and energy storage is almost 100% efficient because it is achieved by the time-shift. Further, per-well production rates can take advantage of the large productivity of horizontal wells, with greater leveraging of well costs, which often constitute a major portion of capital costs for geothermal power systems.

Distributed Energy Resources and Dynamic Microgrid: An Integrated Assessment

NASA Astrophysics Data System (ADS)

Shang, Duo Rick

The overall goal of this thesis is to improve understanding in terms of the benefit of DERs to both utility and to electricity end-users when integrated in power distribution system. To achieve this goal, a series of two studies was conducted to assess the value of DERs when integrated with new power paradigms. First, the arbitrage value of DERs was examined in markets with time-variant electricity pricing rates (e.g., time of use, real time pricing) under a smart grid distribution paradigm. This study uses a stochastic optimization model to estimate the potential profit from electricity price arbitrage over a five-year period. The optimization process involves two types of PHEVs (PHEV-10, and PHEV-40) under three scenarios with different assumptions on technology performance, electricity market and PHEV owner types. The simulation results indicate that expected arbitrage profit is not a viable option to engage PHEVs in dispatching and in providing ancillary services without more favorable policy and PHEV battery technologies. Subsidy or change in electricity tariff or both are needed. Second, it examined the concept of dynamic microgrid as a measure to improve distribution resilience, and estimates the prices of this emerging service. An economic load dispatch (ELD) model is developed to estimate the market-clearing price in a hypothetical community with single bid auction electricity market. The results show that the electricity market clearing price on the dynamic microgrid is predominantly decided by power output and cost of electricity of each type of DGs. At circumstances where CHP is the only source, the electricity market clearing price in the island is even cheaper than the on-grid electricity price at normal times. Integration of PHEVs in the dynamic microgrid will increase electricity market clearing prices. It demonstrates that dynamic microgrid is an economically viable alternative to enhance grid resilience.

Policies to keep and expand the option of concentrating solar power for dispatchable renewable electricity

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

Lilliestam, Johan; Barradi, Touria; Caldes, Natalia

Concentrating solar power (CSP) is one of the few renewable electricity technologies that can offer dispatchable electricity at large scale. Thus, it may play an important role in the future, especially to balance fluctuating sources in increasingly renewables-based power systems. Today, its costs are higher than those of PV and wind power and, as most countries do not support CSP, deployment is slow. Unless the expansion gains pace and costs decrease, the industry may stagnate or collapse, and an important technology for climate change mitigation has been lost. Keeping CSP as a maturing technology for dispatchable renewable power thus requiresmore » measures to improve its short-term economic attractiveness and to continue reducing costs in the longer term. We suggest a set of three policy instruments - feed-in tariffs or auctions reflecting the value of dispatchable CSP, and not merely its cost; risk coverage support for innovative designs; and demonstration projects - to be deployed, in regions where CSP has a potentially large role to play. This could provide the CSP industry with a balance of attractive profits and competitive pressure, the incentive to expand CSP while also reducing its costs, making it ready for broad-scale deployment when it is needed.« less

Policies to keep and expand the option of concentrating solar power for dispatchable renewable electricity

DOE PAGES

Lilliestam, Johan; Barradi, Touria; Caldes, Natalia; ...

2018-02-16

Concentrating solar power (CSP) is one of the few renewable electricity technologies that can offer dispatchable electricity at large scale. Thus, it may play an important role in the future, especially to balance fluctuating sources in increasingly renewables-based power systems. Today, its costs are higher than those of PV and wind power and, as most countries do not support CSP, deployment is slow. Unless the expansion gains pace and costs decrease, the industry may stagnate or collapse, and an important technology for climate change mitigation has been lost. Keeping CSP as a maturing technology for dispatchable renewable power thus requiresmore » measures to improve its short-term economic attractiveness and to continue reducing costs in the longer term. We suggest a set of three policy instruments - feed-in tariffs or auctions reflecting the value of dispatchable CSP, and not merely its cost; risk coverage support for innovative designs; and demonstration projects - to be deployed, in regions where CSP has a potentially large role to play. This could provide the CSP industry with a balance of attractive profits and competitive pressure, the incentive to expand CSP while also reducing its costs, making it ready for broad-scale deployment when it is needed.« less

Research on unit commitment with large-scale wind power connected power system

NASA Astrophysics Data System (ADS)

Jiao, Ran; Zhang, Baoqun; Chi, Zhongjun; Gong, Cheng; Ma, Longfei; Yang, Bing

2017-01-01

Large-scale integration of wind power generators into power grid brings severe challenges to power system economic dispatch due to its stochastic volatility. Unit commitment including wind farm is analyzed from the two parts of modeling and solving methods. The structures and characteristics can be summarized after classification has been done according to different objective function and constraints. Finally, the issues to be solved and possible directions of research and development in the future are discussed, which can adapt to the requirements of the electricity market, energy-saving power generation dispatching and smart grid, even providing reference for research and practice of researchers and workers in this field.

Security and Cloud Outsourcing Framework for Economic Dispatch

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

Sarker, Mushfiqur R.; Wang, Jianhui; Li, Zuyi

The computational complexity and problem sizes of power grid applications have increased significantly with the advent of renewable resources and smart grid technologies. The current paradigm of solving these issues consist of inhouse high performance computing infrastructures, which have drawbacks of high capital expenditures, maintenance, and limited scalability. Cloud computing is an ideal alternative due to its powerful computational capacity, rapid scalability, and high cost-effectiveness. A major challenge, however, remains in that the highly confidential grid data is susceptible for potential cyberattacks when outsourced to the cloud. In this work, a security and cloud outsourcing framework is developed for themore » Economic Dispatch (ED) linear programming application. As a result, the security framework transforms the ED linear program into a confidentiality-preserving linear program, that masks both the data and problem structure, thus enabling secure outsourcing to the cloud. Results show that for large grid test cases the performance gain and costs outperforms the in-house infrastructure.« less

Augmented Lagrange Hopfield network for solving economic dispatch problem in competitive environment

NASA Astrophysics Data System (ADS)

Vo, Dieu Ngoc; Ongsakul, Weerakorn; Nguyen, Khai Phuc

2012-11-01

This paper proposes an augmented Lagrange Hopfield network (ALHN) for solving economic dispatch (ED) problem in the competitive environment. The proposed ALHN is a continuous Hopfield network with its energy function based on augmented Lagrange function for efficiently dealing with constrained optimization problems. The ALHN method can overcome the drawbacks of the conventional Hopfield network such as local optimum, long computational time, and linear constraints. The proposed method is used for solving the ED problem with two revenue models of revenue based on payment for power delivered and payment for reserve allocated. The proposed ALHN has been tested on two systems of 3 units and 10 units for the two considered revenue models. The obtained results from the proposed methods are compared to those from differential evolution (DE) and particle swarm optimization (PSO) methods. The result comparison has indicated that the proposed method is very efficient for solving the problem. Therefore, the proposed ALHN could be a favorable tool for ED problem in the competitive environment.

Security and Cloud Outsourcing Framework for Economic Dispatch

DOE PAGES

Sarker, Mushfiqur R.; Wang, Jianhui; Li, Zuyi; ...

2017-04-24

The computational complexity and problem sizes of power grid applications have increased significantly with the advent of renewable resources and smart grid technologies. The current paradigm of solving these issues consist of inhouse high performance computing infrastructures, which have drawbacks of high capital expenditures, maintenance, and limited scalability. Cloud computing is an ideal alternative due to its powerful computational capacity, rapid scalability, and high cost-effectiveness. A major challenge, however, remains in that the highly confidential grid data is susceptible for potential cyberattacks when outsourced to the cloud. In this work, a security and cloud outsourcing framework is developed for themore » Economic Dispatch (ED) linear programming application. As a result, the security framework transforms the ED linear program into a confidentiality-preserving linear program, that masks both the data and problem structure, thus enabling secure outsourcing to the cloud. Results show that for large grid test cases the performance gain and costs outperforms the in-house infrastructure.« less

DEMONSTRATION OF NATURAL GAS REBURN FOR NOX EMISSIONS REDUCTION AT OHIO EDISON COMPANY'S CYCLONE-FIRED NILES PLANT UNIT NO. 1

EPA Science Inventory

The report describes a demonstration of reburning on a cyclone-fired boiler. The project included a review of reburn technology, aerodynamic flow model testing, long-term load dispatch testing, and boiler tube wall thickness monitoring. The report also contains a description of O...

Defense Threat Reduction Agency > Research > DTRIAC > DTRIAC Dispatch

Science.gov Websites

@mail.mil with your submissions. DTRIAC Dispatch - Vol 5, Issue 3 DTRIAC Dispatch - Vol 5, Issue 2 DTRIAC Dispatch - Vol 5, Issue 1 DTRIAC Dispatch - Vol 4, Issue 1 DTRIAC Dispatch - Vol 3, Issue 4 DTRIAC Dispatch - Vol 3, Issue 3 DTRIAC Dispatch - Vol 3, Issue 2 DTRIAC Dispatch - Vol 3, Issue 1 DTRIAC Dispatch - Vol

Hybridizing a Geothermal Plant with Solar and Thermal Energy Storage to Enhance Power Generation

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

McTigue, Joshua Dominic P; Zhu, Guangdong; Turchi, Craig S

The objective of this project is to identify cost-effective thermal storage systems for a geothermal/solar hybrid system in order to increase the plant dispatchability. Furthermore, an optimal quantity of thermal storage will also be determined to achieve the best economics of a geothermal/solar hybrid plant. NREL is working with Hyperlight Energy and Coso Operating Company to develop techno-economic models of such a system.

Transmission dispatch and congestion management in open market systems

NASA Astrophysics Data System (ADS)

Fang, Risheng

This thesis is located in the domain of electricity supply industry restructuring. It deals with emerging issues, whose understanding is essential to advancing knowledge of open access transmission theory and proceeds to develop approaches for solving the transmission dispatch and congestion management problem. An overview of current trends and experiences in utility restructuring and the main models for restructuring, as well as the classifications of system operators, is first presented. A fully unbundled competitive electricity market model, called the bilateral/multilateral trades model, is then developed. A survey of current research in transmission dispatch and congestion management is included with discussion of transmission capacity and ancillary services. A methodology for the power dispatch problem in a structure dominated by bilateral and multilateral transmission contracts is presented. Group structures are mathematically formulated and explored and three basic types of curtailment strategies proposed for use by market participants. A more complex model is then developed, which takes into account the co-existence of bilateral and multilateral contracts with pool type dynamic supplies and demands based on bids and market clearing prices. An integrated dispatch strategy to reconcile all three types of transactions (bilateral, multilateral and pool) is then developed. Prioritization of electricity transactions and related curtailment strategies are explored and a mechanism for coordination between market participants to achieve additional economic advantages is described. A theory of security based rescheduling is presented in order to investigate the security-related aspects of operation in an unbundled and deregulated system. The impact of post-contingency corrective capability on optimal rescheduling results has been identified and the advantage of incorporating post-contingency corrective rescheduling into the objective function demonstrated. Finally, integrated congestion management procedures in real-time system operation and in forward energy markets are developed. Market price response and coordination of dispatch by the ISO are incorporated to achieve an overall strategy.

Land mobile satellite communication system. Volume 3: Annexes to volume 2: Particular aspects of market analyses

NASA Astrophysics Data System (ADS)

Carnebianca, C.; Pavesi, B.; Tuozzi, A.; Capone, R.

1986-06-01

The socioeconomic desirability in terms of market demand, technical economic feasibility, and price-performance for a Land Mobile Communication system ground based and/or satellite aided, able to satisfy the request of the traffic demand, foreseeable in the 1995 to 2005 time frame, for the Western European countries was assessed. The criterion of economic value of the mobile system is considered as the driving element. Data on traffic; socioeconomic factors; economic factors; and radiotelephony, paging, and dispatch subscription and value for money trends are presented.

Modeling and Economic Analysis of Power Grid Operations in a Water Constrained System

NASA Astrophysics Data System (ADS)

Zhou, Z.; Xia, Y.; Veselka, T.; Yan, E.; Betrie, G.; Qiu, F.

2016-12-01

The power sector is the largest water user in the United States. Depending on the cooling technology employed at a facility, steam-electric power stations withdrawal and consume large amounts of water for each megawatt hour of electricity generated. The amounts are dependent on many factors, including ambient air and water temperatures, cooling technology, etc. Water demands from most economic sectors are typically highest during summertime. For most systems, this coincides with peak electricity demand and consequently a high demand for thermal power plant cooling water. Supplies however are sometimes limited due to seasonal precipitation fluctuations including sporadic droughts that lead to water scarcity. When this occurs there is an impact on both unit commitments and the real-time dispatch. In this work, we model the cooling efficiency of several different types of thermal power generation technologies as a function of power output level and daily temperature profiles. Unit specific relationships are then integrated in a power grid operational model that minimizes total grid production cost while reliably meeting hourly loads. Grid operation is subject to power plant physical constraints, transmission limitations, water availability and environmental constraints such as power plant water exit temperature limits. The model is applied to a standard IEEE-118 bus system under various water availability scenarios. Results show that water availability has a significant impact on power grid economics.

Multi-time Scale Joint Scheduling Method Considering the Grid of Renewable Energy

NASA Astrophysics Data System (ADS)

Zhijun, E.; Wang, Weichen; Cao, Jin; Wang, Xin; Kong, Xiangyu; Quan, Shuping

2018-01-01

Renewable new energy power generation prediction error like wind and light, brings difficulties to dispatch the power system. In this paper, a multi-time scale robust scheduling method is set to solve this problem. It reduces the impact of clean energy prediction bias to the power grid by using multi-time scale (day-ahead, intraday, real time) and coordinating the dispatching power output of various power supplies such as hydropower, thermal power, wind power, gas power and. The method adopts the robust scheduling method to ensure the robustness of the scheduling scheme. By calculating the cost of the abandon wind and the load, it transforms the robustness into the risk cost and optimizes the optimal uncertainty set for the smallest integrative costs. The validity of the method is verified by simulation.

An Evaluation of the HVAC Load Potential for Providing Load Balancing Service

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

Lu, Ning

This paper investigates the potential of providing aggregated intra-hour load balancing services using heating, ventilating, and air-conditioning (HVAC) systems. A direct-load control algorithm is presented. A temperature-priority-list method is used to dispatch the HVAC loads optimally to maintain consumer-desired indoor temperatures and load diversity. Realistic intra-hour load balancing signals were used to evaluate the operational characteristics of the HVAC load under different outdoor temperature profiles and different indoor temperature settings. The number of HVAC units needed is also investigated. Modeling results suggest that the number of HVACs needed to provide a {+-}1-MW load balancing service 24 hours a day variesmore » significantly with baseline settings, high and low temperature settings, and the outdoor temperatures. The results demonstrate that the intra-hour load balancing service provided by HVAC loads meet the performance requirements and can become a major source of revenue for load-serving entities where the smart grid infrastructure enables direct load control over the HAVC loads.« less

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

Smith, L.L.; Hooper, M.

This report summarizes the activities and results for the second testing phase (Phase 2) of an Innovative Clean Coal Technology (ICCT) demonstration of advanced tangentially fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. All three levels of Asea Brown Boveri Combustion Engineering Service`s (ABB CE`s) Low-NO{sub x} Concentric Firing System (LNCFS) are being demonstrated during this project. The primary goal of this project is to demonstrate the NO{sub x} emissions characteristics of these technologies when operated under normal load dispatched conditions. The equipment is being tested at Gulf Power Company`s Plant Lansing Smith Unitmore » 2 in Lynn Haven, Florida. The long-term NO{sub x} emission trends were documented while the unit was operating under normal load dispatch conditions with the LNCFS Level II equipment. Fifty-five days of long-term data were collected. The data included the effects of mill patterns, unit load, mill outages, weather, fuel variability, and load swings. Test results indicated full-load (180 MW) NO{sub x} emissions of 0.39 lb/MBtu, which is about equal to the short-term test results. At 110 MW, long-term NO{sub x} emissions increased to 0.42 lb/MBtu, which are slightly higher than the short-term data. At 75 MW, NO{sub x} emissions were 0.51 lb/MBtu, which is significantly higher than the short-term data. The annual and 30-day average achievable NOx emissions were determined to be 0.41 and 0.45 lb/MBtu, respectively, for long-term testing load scenarios. NO{sub x} emissions were reduced by a maximum of 40 percent when compared to the baseline data collected in the previous phase. The long-term NO{sub x} reduction at full load (180 MW) was 37 percent while NO{sub x} reduction at low load was minimal.« less

Fixed-speed and Variable-speed Pumped Storage Dispatch Model in Power Systems with High Renewable Penetration

NASA Astrophysics Data System (ADS)

Yuan, Bo; Zong, Jin; Xu, Zhicheng

2018-06-01

According to different operating characteristics of pumped storage fixed speed unit and variable speed unit, a joint dispatching model of pumped storage unit and other types of units based on mixed integer linear optimization is constructed. The model takes into account the operating conditions, reservoir capacity, cycle type and other pumped storage unit constraints, but also consider the frequent start and stop and the stability of the operation of the unit caused by the loss. Using the Cplex solver to solve the model, the empirical example of the provincial power grid shows that the model can effectively arrange the pumping storage speed and the dispatching operation of the variable speed unit under the precondition of economic life of the unit, and give full play to the function of peak shaving and accommodating new energy. Because of its more flexible regulation characteristics of power generation and pumping conditions, the variable speed unit can better improve the operating conditions of other units in the system and promote the new energy dissipation.

Estimating the Performance and Economic Value of Multiple Concentrating Solar Power Technologies in a Production Cost Model

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

Jorgenson, Jennie; Denholm, Paul; Mehos, Mark

2013-12-01

Concentrating solar power with thermal energy storage (CSP-TES) is a unique source of renewable energy in that the solar thermal energy can be dispatched similarly to conventional thermal generation. However, CSP-TES plants are energy-limited, meaning that their response might be restricted by solar availability. Therefore, the use of this limited solar energy must be optimally scheduled toprovide the greatest value to the system. The timing of CSP-TES dispatch depends on a variety of factors, including electricity demand patterns, the penetration of variable generation sources, and the configuration of the CSP-TES plant itself. We use an established CSP-TES modeling framework inmore » a commercially available production cost model to compare the dispatch and value of two CSP-TEStechnologies (molten salt towers and parabolic troughs) in a Colorado test system. In addition, we consider a range of configuration parameters, such as the solar multiple and thermal energy storage limit, to evaluate how the operational and capacity value varies with plant configuration.« less

Emissions and Cost Implications of Controlled Electric Vehicle Charging in the U.S. PJM Interconnection.

PubMed

Weis, Allison; Michalek, Jeremy J; Jaramillo, Paulina; Lueken, Roger

2015-05-05

We develop a unit commitment and economic dispatch model to estimate the operation costs and the air emissions externality costs attributable to new electric vehicle electricity demand under controlled vs uncontrolled charging schemes. We focus our analysis on the PJM Interconnection and use scenarios that characterize (1) the most recent power plant fleet for which sufficient data are available, (2) a hypothetical 2018 power plant fleet that reflects upcoming plant retirements, and (3) the 2018 fleet with increased wind capacity. We find that controlled electric vehicle charging can reduce associated generation costs by 23%-34% in part by shifting loads to lower-cost, higher-emitting coal plants. This shift results in increased externality costs of health and environmental damages from increased air pollution. On balance, we find that controlled charging of electric vehicles produces negative net social benefits in the recent PJM grid but could have positive net social benefits in a future grid with sufficient coal retirements and wind penetration.

Decentralized DC Microgrid Monitoring and Optimization via Primary Control Perturbations

NASA Astrophysics Data System (ADS)

Angjelichinoski, Marko; Scaglione, Anna; Popovski, Petar; Stefanovic, Cedomir

2018-06-01

We treat the emerging power systems with direct current (DC) MicroGrids, characterized with high penetration of power electronic converters. We rely on the power electronics to propose a decentralized solution for autonomous learning of and adaptation to the operating conditions of the DC Mirogrids; the goal is to eliminate the need to rely on an external communication system for such purpose. The solution works within the primary droop control loops and uses only local bus voltage measurements. Each controller is able to estimate (i) the generation capacities of power sources, (ii) the load demands, and (iii) the conductances of the distribution lines. To define a well-conditioned estimation problem, we employ decentralized strategy where the primary droop controllers temporarily switch between operating points in a coordinated manner, following amplitude-modulated training sequences. We study the use of the estimator in a decentralized solution of the Optimal Economic Dispatch problem. The evaluations confirm the usefulness of the proposed solution for autonomous MicroGrid operation.

Simulation of hybrid solar power plants

NASA Astrophysics Data System (ADS)

Dieckmann, Simon; Dersch, Jürgen

2017-06-01

Hybrid solar power plants have the potential to combine advantages of two different technologies at the cost of increased complexity. The present paper shows the potential of the software greenius for the techno-economic evaluation of hybrid solar power plants and discusses two exemplary scenarios. Depreciated Concentrated Solar Power (CSP) plants based on trough technology can be retrofitted with solar towers in order to reach higher steam cycle temperatures and hence efficiencies. Compared to a newly built tower plant the hybridization of a depreciated trough plant causes about 30% lower LCOE reaching 104 /MWh. The second hybrid scenario combines cost-efficient photovoltaics with dispatchable CSP technology. This hybrid plant offers very high capacity factors up to 69% based on 100% load from 8am to 11pm. The LCOE of the hybrid plant are only slightly lower (174 vs. 186 /MWh) compared to the pure CSP plant because the capital expenditure for thermal storage and power block remains the same while the electricity output is much lower.

Three-stage variability-based reserve modifiers for enhancing flexibility reserve requirements under high variable generation penetrations

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

Krad, Ibrahim; Gao, David Wenzhong; Ibanez, Eduardo

2016-12-01

The electric power system has continuously evolved in order to accommodate new technologies and operating strategies. As the penetration of integrated variable generation in the system increases, it is beneficial to develop strategies that can help mitigate their effect on the grid. Historically, power system operators have held excess capacity during the commitment and dispatch process to allow the system to handle unforeseen load ramping events. As variable generation resources increase, sufficient flexibility scheduled in the system is required to ensure that system performance is not deteriorated in the presence of additional variability and uncertainty. This paper presents a systematicmore » comparison of various flexibility reserve strategies. Several of them are implemented and applied in a common test system, in order to evaluate their effect on the economic and reliable operations. Furthermore, a three stage reserve modifier algorithm is proposed and evaluated for its ability to improve system performance.« less

Development of Quadratic Programming Algorithm Based on Interior Point Method with Estimation Mechanism of Active Constraints

NASA Astrophysics Data System (ADS)

Hashimoto, Hiroyuki; Takaguchi, Yusuke; Nakamura, Shizuka

Instability of calculation process and increase of calculation time caused by increasing size of continuous optimization problem remain the major issues to be solved to apply the technique to practical industrial systems. This paper proposes an enhanced quadratic programming algorithm based on interior point method mainly for improvement of calculation stability. The proposed method has dynamic estimation mechanism of active constraints on variables, which fixes the variables getting closer to the upper/lower limit on them and afterwards releases the fixed ones as needed during the optimization process. It is considered as algorithm-level integration of the solution strategy of active-set method into the interior point method framework. We describe some numerical results on commonly-used bench-mark problems called “CUTEr” to show the effectiveness of the proposed method. Furthermore, the test results on large-sized ELD problem (Economic Load Dispatching problems in electric power supply scheduling) are also described as a practical industrial application.

Energy conservation, energy efficiency and energy savings regulatory hypotheses - taxation, subsidies and underlying economics

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

Trumpy, T.

1995-12-01

More efficient use of energy resources can be promoted by various regulatory means, i.e., taxation, subsidies, and pricing. Various incentives can be provided by income and revenue tax breaks-deductible energy audit fees, energy saving investment credits, breaks for energy saving entrepreneurs, and energy savings accounts run through utility accounts. Value added and excise taxes can also be adjusted to reward energy saving investments and energy saving entrepreneurial activity. Incentives can be provided in the form of cash refunds, including trade-in-and-scrap programs and reimbursements or subsidies on audit costs and liability insurance. Pricing incentives include lower rates for less energy use,more » prepayment of deposit related to peak load use, electronically dispatched multiple tariffs, savings credits based on prior peak use, and subsidized {open_quotes}leasing{close_quotes} of more efficient appliances and lights. Credits, with an emphasis on pooling small loans, and 5-year energy savings contracts are also discussed.« less

Thermodynamic Modeling and Dispatch of Distributed Energy Technologies including Fuel Cell -- Gas Turbine Hybrids

NASA Astrophysics Data System (ADS)

McLarty, Dustin Fogle

Distributed energy systems are a promising means by which to reduce both emissions and costs. Continuous generators must be responsive and highly efficiency to support building dynamics and intermittent on-site renewable power. Fuel cell -- gas turbine hybrids (FC/GT) are fuel-flexible generators capable of ultra-high efficiency, ultra-low emissions, and rapid power response. This work undertakes a detailed study of the electrochemistry, chemistry and mechanical dynamics governing the complex interaction between the individual systems in such a highly coupled hybrid arrangement. The mechanisms leading to the compressor stall/surge phenomena are studied for the increased risk posed to particular hybrid configurations. A novel fuel cell modeling method introduced captures various spatial resolutions, flow geometries, stack configurations and novel heat transfer pathways. Several promising hybrid configurations are analyzed throughout the work and a sensitivity analysis of seven design parameters is conducted. A simple estimating method is introduced for the combined system efficiency of a fuel cell and a turbine using component performance specifications. Existing solid oxide fuel cell technology is capable of hybrid efficiencies greater than 75% (LHV) operating on natural gas, and existing molten carbonate systems greater than 70% (LHV). A dynamic model is calibrated to accurately capture the physical coupling of a FC/GT demonstrator tested at UC Irvine. The 2900 hour experiment highlighted the sensitivity to small perturbations and a need for additional control development. Further sensitivity studies outlined the responsiveness and limits of different control approaches. The capability for substantial turn-down and load following through speed control and flow bypass with minimal impact on internal fuel cell thermal distribution is particularly promising to meet local demands or provide dispatchable support for renewable power. Advanced control and dispatch heuristics are discussed using a case study of the UCI central plant. Thermal energy storage introduces a time horizon into the dispatch optimization which requires novel solution strategies. Highly efficient and responsive generators are required to meet the increasingly dynamic loads of today's efficient buildings and intermittent local renewable wind and solar power. Fuel cell gas turbine hybrids will play an integral role in the complex and ever-changing solution to local electricity production.

The Eastern Renewable Generation Integration Study: Insights on System Stress: Preprint

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

Bloom, Aaron; Novacheck, Josh

The Eastern Renewable Generation Integration Study (ERGIS) explores the operational impacts of the wide spread adoption of wind and solar photovoltaics (PV) resources in North America's Eastern and Quebec Interconnections. We explore the impact of large scale adoption of wind and solar generation on the unit commitment and economic dispatch of the largest coordinated power system in the world by simulating hourly and five-minute operations. Using NREL's high-performance computing capabilities and new methodologies to model operations, we found that the modeled system, as simulated with evolutionary change in 2026, could balance the variability and uncertainty of wind and solar PVmore » at a five-minute level under a variety of conditions. Our simulations achieve instantaneous penetrations that exceed 50% of load while meeting an annual penetration of 30% on an energy basis. The system meets balanced load and supply in all intervals, with modest curtailment, using technologies and practices that are widely available today. However, a variety of the conditions present in these simulations deviate substantially from historical practice. In this work, we analyze potentially stressful system conditions that occur in the simulations and identify opportunities for innovation, regulatory reform, and changes in operating practices that require further analysis to enable the transition to a system with more wind and solar PV.« less

System-wide emissions implications of increased wind power penetration.

PubMed

Valentino, Lauren; Valenzuela, Viviana; Botterud, Audun; Zhou, Zhi; Conzelmann, Guenter

2012-04-03

This paper discusses the environmental effects of incorporating wind energy into the electric power system. We present a detailed emissions analysis based on comprehensive modeling of power system operations with unit commitment and economic dispatch for different wind penetration levels. First, by minimizing cost, the unit commitment model decides which thermal power plants will be utilized based on a wind power forecast, and then, the economic dispatch model dictates the level of production for each unit as a function of the realized wind power generation. Finally, knowing the power production from each power plant, the emissions are calculated. The emissions model incorporates the effects of both cycling and start-ups of thermal power plants in analyzing emissions from an electric power system with increasing levels of wind power. Our results for the power system in the state of Illinois show significant emissions effects from increased cycling and particularly start-ups of thermal power plants. However, we conclude that as the wind power penetration increases, pollutant emissions decrease overall due to the replacement of fossil fuels.

Economical Video Monitoring of Traffic

NASA Technical Reports Server (NTRS)

Houser, B. C.; Paine, G.; Rubenstein, L. D.; Parham, O. Bruce, Jr.; Graves, W.; Bradley, C.

1986-01-01

Data compression allows video signals to be transmitted economically on telephone circuits. Telephone lines transmit television signals to remote traffic-control center. Lines also carry command signals from center to TV camera and compressor at highway site. Video system with television cameras positioned at critical points on highways allows traffic controllers to determine visually, almost immediately, exact cause of traffic-flow disruption; e.g., accidents, breakdowns, or spills, almost immediately. Controllers can then dispatch appropriate emergency services and alert motorists to minimize traffic backups.

View of button board which accommodates the 1200 button switches ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of button board which accommodates the 1200 button switches which manually control the indicating pilot lights on the model board. Not all switches are active, some switches were installed for a planned, but never constructed, system expansion. - Thirtieth Street Station, Load Dispatch Center, Thirtieth & Market Streets, Railroad Station, Amtrak (formerly Pennsylvania Railroad Station), Philadelphia, Philadelphia County, PA

Closeup view of leeds and northrup strip chart recorders used ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Close-up view of leeds and northrup strip chart recorders used to indicate power usage on certain portions of the system. Note model board builders plaque which reads Kellogg Switchboard and Supply Company- Chicago, USA at left center of photograph. - Thirtieth Street Station, Load Dispatch Center, Thirtieth & Market Streets, Railroad Station, Amtrak (formerly Pennsylvania Railroad Station), Philadelphia, Philadelphia County, PA

Solar Energy Grid Integration Systems (SEGIS): adding functionality while maintaining reliability and economics

NASA Astrophysics Data System (ADS)

Bower, Ward

2011-09-01

An overview of the activities and progress made during the US DOE Solar Energy Grid Integration Systems (SEGIS) solicitation, while maintaining reliability and economics is provided. The SEGIS R&D opened pathways for interconnecting PV systems to intelligent utility grids and micro-grids of the future. In addition to new capabilities are "value added" features. The new hardware designs resulted in smaller, less material-intensive products that are being viewed by utilities as enabling dispatchable generation and not just unpredictable negative loads. The technical solutions enable "advanced integrated system" concepts and "smart grid" processes to move forward in a faster and focused manner. The advanced integrated inverters/controllers can now incorporate energy management functionality, intelligent electrical grid support features and a multiplicity of communication technologies. Portals for energy flow and two-way communications have been implemented. SEGIS hardware was developed for the utility grid of today, which was designed for one-way power flow, for intermediate grid scenarios, AND for the grid of tomorrow, which will seamlessly accommodate managed two-way power flows as required by large-scale deployment of solar and other distributed generation. The SEGIS hardware and control developed for today meets existing standards and codes AND provides for future connections to a "smart grid" mode that enables utility control and optimized performance.

Residential Solar PV Systems in the Carolinas: Opportunities and Outcomes.

PubMed

Alqahtani, Bandar Jubran; Holt, Kyra Moore; Patiño-Echeverri, Dalia; Pratson, Lincoln

2016-02-16

This paper presents a first-order analysis of the feasibility and technical, environmental, and economic effects of large levels of solar photovoltaic (PV) penetration within the services areas of the Duke Energy Carolinas (DEC) and Duke Energy Progress (DEP). A PV production model based on household density and a gridded hourly global horizontal irradiance data set simulates hourly PV power output from roof-top installations, while a unit commitment and real-time economic dispatch (UC-ED) model simulates hourly system operations. We find that the large generating capacity of base-load nuclear power plants (NPPs) without ramping capability in the region limits PV integration levels to 5.3% (6510 MW) of 2015 generation. Enabling ramping capability for NPPs would raise the limit of PV penetration to near 9% of electricity generated. If the planned retirement of coal-fired power plants together with new installations and upgrades of natural gas and nuclear plants materialize in 2025, and if NPPs operate flexibly, then the share of coal-fired electricity will be reduced from 37% to 22%. A 9% penetration of electricity from PV would further reduce the share of coal-fired electricity by 4-6% resulting in a system-wide CO2 emissions rate of 0.33 to 0.40 tons/MWh and associated abatement costs of 225-415 (2015$ per ton).

Optimal Real-time Dispatch for Integrated Energy Systems

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

Firestone, Ryan Michael

This report describes the development and application of a dispatch optimization algorithm for integrated energy systems (IES) comprised of on-site cogeneration of heat and electricity, energy storage devices, and demand response opportunities. This work is intended to aid commercial and industrial sites in making use of modern computing power and optimization algorithms to make informed, near-optimal decisions under significant uncertainty and complex objective functions. The optimization algorithm uses a finite set of randomly generated future scenarios to approximate the true, stochastic future; constraints are included that prevent solutions to this approximate problem from deviating from solutions to the actual problem.more » The algorithm is then expressed as a mixed integer linear program, to which a powerful commercial solver is applied. A case study of United States Postal Service Processing and Distribution Centers (P&DC) in four cities and under three different electricity tariff structures is conducted to (1) determine the added value of optimal control to a cogeneration system over current, heuristic control strategies; (2) determine the value of limited electric load curtailment opportunities, with and without cogeneration; and (3) determine the trade-off between least-cost and least-carbon operations of a cogeneration system. Key results for the P&DC sites studied include (1) in locations where the average electricity and natural gas prices suggest a marginally profitable cogeneration system, optimal control can add up to 67% to the value of the cogeneration system; optimal control adds less value in locations where cogeneration is more clearly profitable; (2) optimal control under real-time pricing is (a) more complicated than under typical time-of-use tariffs and (b) at times necessary to make cogeneration economic at all; (3) limited electric load curtailment opportunities can be more valuable as a compliment to the cogeneration system than alone; and (4) most of the trade-off between least-cost and least-carbon IES is determined during the system design stage; for the IES system considered, there is little difference between least-cost control and least-carbon control.« less

A maintenance model for k-out-of-n subsystems aboard a fleet of advanced commercial aircraft

NASA Technical Reports Server (NTRS)

Miller, D. R.

1978-01-01

Proposed highly reliable fault-tolerant reconfigurable digital control systems for a future generation of commercial aircraft consist of several k-out-of-n subsystems. Each of these flight-critical subsystems will consist of n identical components, k of which must be functioning properly in order for the aircraft to be dispatched. Failed components are recoverable; they are repaired in a shop. Spares are inventoried at a main base where they may be substituted for failed components on planes during layovers. Penalties are assessed when failure of a k-out-of-n subsystem causes a dispatch cancellation or delay. A maintenance model for a fleet of aircraft with such control systems is presented. The goals are to demonstrate economic feasibility and to optimize.

Implications of low natural gas prices on life cycle greenhouse gas emissions in the U.S. electricity sector

NASA Astrophysics Data System (ADS)

Jaramillo, P.; Venkatesh, A.; Griffin, M.; Matthews, S.

2012-12-01

Increased production of unconventional natural gas resources in the U.S. has drastically reduced the price of natural gas. While in 2005 prices went above 10/MMBtu, since 2011 they have been below 3/MMBtu. These low prices have encouraged the increase of natural gas utilization in the United States electricity sector. Natural gas can offset coal for power generation, reducing emissions such as greenhouse gases, sulfur and nitrogen oxides. In quantifying the benefit of offsetting coal by using natural gas, life cycle assessment (LCA) studies have shown up to 50% reductions in life cycle greenhouse gas (GHG) emissions can be expected. However, these studies predominantly use limited system boundaries that contain single individual coal and natural gas power plants. They do not consider (regional) fleets of power plants that are dispatched on the basis of their short-run marginal costs. In this study, simplified economic dispatch models (representing existing power plants in a given region) are developed for three U.S. regions - ERCOT, MISO and PJM. These models, along with historical load data are used to determine how natural gas utilization will increase in the short-term due to changes in natural gas price. The associated changes in fuel mix and life cycle GHG emissions are estimated. Results indicate that life cycle GHG emissions may, at best, decrease by 5-15% as a result of low natural gas prices, compared to almost 50% reductions estimated by previous LCAs. This study thus provides more reasonable estimates of potential reductions in GHG emissions from using natural gas instead of coal in the electricity sector in the short-term.

Parallel dispatch: a new paradigm of electrical power system dispatch

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

Zhang, Jun Jason; Wang, Fei-Yue; Wang, Qiang

Modern power systems are evolving into sociotechnical systems with massive complexity, whose real-time operation and dispatch go beyond human capability. Thus, the need for developing and applying new intelligent power system dispatch tools are of great practical significance. In this paper, we introduce the overall business model of power system dispatch, the top level design approach of an intelligent dispatch system, and the parallel intelligent technology with its dispatch applications. We expect that a new dispatch paradigm, namely the parallel dispatch, can be established by incorporating various intelligent technologies, especially the parallel intelligent technology, to enable secure operation of complexmore » power grids, extend system operators U+02BC capabilities, suggest optimal dispatch strategies, and to provide decision-making recommendations according to power system operational goals.« less

Wind Energy Management System Integration Project Incorporating Wind Generation and Load Forecast Uncertainties into Power Grid Operations

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

Makarov, Yuri V.; Huang, Zhenyu; Etingov, Pavel V.

2010-09-01

The power system balancing process, which includes the scheduling, real time dispatch (load following) and regulation processes, is traditionally based on deterministic models. Since the conventional generation needs time to be committed and dispatched to a desired megawatt level, the scheduling and load following processes use load and wind power production forecasts to achieve future balance between the conventional generation and energy storage on the one side, and system load, intermittent resources (such as wind and solar generation) and scheduled interchange on the other side. Although in real life the forecasting procedures imply some uncertainty around the load and windmore » forecasts (caused by forecast errors), only their mean values are actually used in the generation dispatch and commitment procedures. Since the actual load and intermittent generation can deviate from their forecasts, it becomes increasingly unclear (especially, with the increasing penetration of renewable resources) whether the system would be actually able to meet the conventional generation requirements within the look-ahead horizon, what the additional balancing efforts would be needed as we get closer to the real time, and what additional costs would be incurred by those needs. In order to improve the system control performance characteristics, maintain system reliability, and minimize expenses related to the system balancing functions, it becomes necessary to incorporate the predicted uncertainty ranges into the scheduling, load following, and, in some extent, into the regulation processes. It is also important to address the uncertainty problem comprehensively, by including all sources of uncertainty (load, intermittent generation, generators’ forced outages, etc.) into consideration. All aspects of uncertainty such as the imbalance size (which is the same as capacity needed to mitigate the imbalance) and generation ramping requirement must be taken into account. The latter unique features make this work a significant step forward toward the objective of incorporating of wind, solar, load, and other uncertainties into power system operations. In this report, a new methodology to predict the uncertainty ranges for the required balancing capacity, ramping capability and ramp duration is presented. Uncertainties created by system load forecast errors, wind and solar forecast errors, generation forced outages are taken into account. The uncertainty ranges are evaluated for different confidence levels of having the actual generation requirements within the corresponding limits. The methodology helps to identify system balancing reserve requirement based on a desired system performance levels, identify system “breaking points”, where the generation system becomes unable to follow the generation requirement curve with the user-specified probability level, and determine the time remaining to these potential events. The approach includes three stages: statistical and actual data acquisition, statistical analysis of retrospective information, and prediction of future grid balancing requirements for specified time horizons and confidence intervals. Assessment of the capacity and ramping requirements is performed using a specially developed probabilistic algorithm based on a histogram analysis incorporating all sources of uncertainty and parameters of a continuous (wind forecast and load forecast errors) and discrete (forced generator outages and failures to start up) nature. Preliminary simulations using California Independent System Operator (California ISO) real life data have shown the effectiveness of the proposed approach. A tool developed based on the new methodology described in this report will be integrated with the California ISO systems. Contractual work is currently in place to integrate the tool with the AREVA EMS system.« less

Cancellations of (helicopter-transported) mobile medical team dispatches in the Netherlands.

PubMed

Giannakopoulos, Georgios F; Lubbers, Wouter D; Christiaans, Herman M T; van Exter, Pieternel; Bet, Piet; Hugen, Paul J C; Innemee, Gerard; Schubert, Edo; de Lange-Klerk, Elly S M; Goslings, J Carel; Jukema, Gerrolt N

2010-08-01

The trauma centre of the Trauma Center Region North-West Netherlands (TRNWN) has consensus criteria for Mobile Medical Team (MMT) scene dispatch. The MMT can be dispatched by the EMS-dispatch centre or by the on-scene ambulance crew and is transported by helicopter or ground transport. Although much attention has been paid to improve the dispatch criteria, the MMT is often cancelled after being dispatched. The aim of this study was to assess the cancellation rate and the noncompliant dispatches of our MMT and to identify factors associated with this form of primary overtriage. By retrospective analysis of all MMT dispatches in the period from 1 July 2006 till 31 December 2006 using chart review, we conducted a consecutive case review of 605 dispatches. Four hundred and sixty seven of these were included for our study, collecting data related to prehospital triage, patient's condition on-scene and hospital course. Average age was 35.9 years; the majority of the patients were male (65.3%). Four hundred and thirty patients were victims of trauma, sustaining injuries in most cases from blunt trauma (89.3%). After being dispatched, the MMT was cancelled 203 times (43.5%). Statistically significant differences between assists and cancellations were found for overall mortality, mean RTS, GCS and ISS, mean hospitalization, length and amount of ICU admissions (p < 0.001). All dispatches were evaluated by using the MMT-dispatch criteria and mission appropriateness criteria. Almost 26% of all dispatches were neither appropriate, nor met the dispatch criteria. Fourteen missions were appropriate, but did not meet the dispatch criteria. The remaining 318 dispatches had met the dispatch criteria, of which 135 (30.3%) were also appropriate. The calculated additional costs of the cancelled dispatches summed up to a total of 34,448 euro, amounting to 2.2% of the total MMT costs during the study period. In our trauma system, the MMT dispatches are involved with high rates of overtriage. After being dispatched, the MMT is cancelled in almost 50% of all cases. We found an undertriage rate of 4%, which we think is acceptable. All cancellations were justified. The additional costs of the cancelled missions were within an acceptable range. According to this study, it seems to be possible to reduce the overtriage rate of the MMT dispatches, without increasing the undertriage rate to non-acceptable levels.

Evaluating the Technical and Economic Performance of PV Plus Storage Power Plants: Report Summary

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

Denholm, Paul L.; Margolis, Robert M.; Eichman, Joshua D.

The decreasing costs of both PV and energy storage technologies have raised interest in the creation of combined PV plus storage systems to provide dispatchable energy and reliable capacity. In this study, we examine the tradeoffs among various PV plus storage configurations and quantify the impact of configuration on system net value.

Evaluating the Technical and Economic Performance of PV Plus Storage Power Plants

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

Denholm, Paul L.; Margolis, Robert M.; Eichman, Joshua D.

The decreasing costs of both PV and energy storage technologies have raised interest in the creation of combined PV plus storage systems to provide dispatchable energy and reliable capacity. In this study, we examine the tradeoffs among various PV plus storage configurations and quantify the impact of configuration on system net value.

76 FR 61137 - Hours of Service of Drivers: Western Pilot Service Application for Exemption

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-03

... the 70th hour of cumulative on-duty time in any 8-day period. FMCSA requests public comment on the... and be ready to mix, load, fuel, and service its aircraft at all times during daylight hours and must... and mental work in a given day. While Western's drivers wait for an aircraft to be dispatched or land...

Dynamic modeling and evaluation of solid oxide fuel cell - combined heat and power system operating strategies

NASA Astrophysics Data System (ADS)

Nanaeda, Kimihiro; Mueller, Fabian; Brouwer, Jacob; Samuelsen, Scott

Operating strategies of solid oxide fuel cell (SOFC) combined heat and power (CHP) systems are developed and evaluated from a utility, and end-user perspective using a fully integrated SOFC-CHP system dynamic model that resolves the physical states, thermal integration and overall efficiency of the system. The model can be modified for any SOFC-CHP system, but the present analysis is applied to a hotel in southern California based on measured electric and heating loads. Analysis indicates that combined heat and power systems can be operated to benefit both the end-users and the utility, providing more efficient electric generation as well as grid ancillary services, namely dispatchable urban power. Design and operating strategies considered in the paper include optimal sizing of the fuel cell, thermal energy storage to dispatch heat, and operating the fuel cell to provide flexible grid power. Analysis results indicate that with a 13.1% average increase in price-of-electricity (POE), the system can provide the grid with a 50% operating range of dispatchable urban power at an overall thermal efficiency of 80%. This grid-support operating mode increases the operational flexibility of the SOFC-CHP system, which may make the technology an important utility asset for accommodating the increased penetration of intermittent renewable power.

Reliability Constrained Priority Load Shedding for Aerospace Power System Automation

NASA Technical Reports Server (NTRS)

Momoh, James A.; Zhu, Jizhong; Kaddah, Sahar S.; Dolce, James L. (Technical Monitor)

2000-01-01

The need for improving load shedding on board the space station is one of the goals of aerospace power system automation. To accelerate the optimum load-shedding functions, several constraints must be involved. These constraints include congestion margin determined by weighted probability contingency, component/system reliability index, generation rescheduling. The impact of different faults and indices for computing reliability were defined before optimization. The optimum load schedule is done based on priority, value and location of loads. An optimization strategy capable of handling discrete decision making, such as Everett optimization, is proposed. We extended Everett method to handle expected congestion margin and reliability index as constraints. To make it effective for real time load dispatch process, a rule-based scheme is presented in the optimization method. It assists in selecting which feeder load to be shed, the location of the load, the value, priority of the load and cost benefit analysis of the load profile is included in the scheme. The scheme is tested using a benchmark NASA system consisting of generators, loads and network.

Distributed Optimal Dispatch of Distributed Energy Resources Over Lossy Communication Networks

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

Wu, Junfeng; Yang, Tao; Wu, Di

In this paper, we consider the economic dispatch problem (EDP), where a cost function that is assumed to be strictly convex is assigned to each of distributed energy resources (DERs), over packet dropping networks. The goal of a standard EDP is to minimize the total generation cost while meeting total demand and satisfying individual generator output limit. We propose a distributed algorithm for solving the EDP over networks. The proposed algorithm is resilient against packet drops over communication links. Under the assumption that the underlying communication network is strongly connected with a positive probability and the packet drops are independentmore » and identically distributed (i.i.d.), we show that the proposed algorithm is able to solve the EDP. Numerical simulation results are used to validate and illustrate the main results of the paper.« less

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

Simpkins, Travis; Cutler, Dylan; Hirsch, Brian

There are thousands of isolated, diesel-powered microgrids that deliver energy to remote communities around the world at very high energy costs. The Remote Communities Renewable Energy program aims to help these communities reduce their fuel consumption and lower their energy costs through the use of high penetration renewable energy. As part of this program, the REopt modeling platform for energy system integration and optimization was used to analyze cost-optimal pathways toward achieving a combined 75% reduction in diesel fuel and fuel oil consumption in a select Alaskan village. In addition to the existing diesel generator and fuel oil heating technologies,more » the model was able to select from among wind, battery storage, and dispatchable electric heaters to meet the electrical and thermal loads. The model results indicate that while 75% fuel reduction appears to be technically feasible it may not be economically viable at this time. When the fuel reduction target was relaxed, the results indicate that by installing high-penetration renewable energy, the community could lower their energy costs by 21% while still reducing their fuel consumption by 54%.« less

Electricity Market Module - NEMS Documentation

EIA Publications

2017-01-01

Documents the Electricity Market Module as it was used for the Annual Energy Outlook. The Electricity Market Module (EMM) is the electricity supply component of the National Energy Modeling System (NEMS). The EMM represents the generation, transmission, and pricing of electricity. It consists of four submodules: the Electricity Capacity Planning (ECP) Submodule, the Electricity Fuel Dispatch (EFD) Submodule, the Electricity Finance and Pricing (EFP) Submodule, and the Electricity Load and Demand (ELD) Submodule.

Emissions implications of downscaled electricity generation scenarios for the western United States

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

Nsanzineza, Rene; O’Connell, Matthew; Brinkman, Gregory

This study explores how emissions from electricity generation in the Western Interconnection region of the U.S. might respond in circa 2030 to contrasting scenarios for fuel prices and greenhouse gas (GHG) emissions fees. We examine spatial and temporal variations in generation mix across the region and year using the PLEXOS unit commitment and dispatch model with a production cost model database adapted from the Western Electricity Coordinating Council. Emissions estimates are computed by combining the dispatch model results with unit-specific, emissions-load relationships. Wind energy displaces natural gas and coal in scenarios with relatively expensive natural gas or with GHG fees.more » Correspondingly, annual emissions of NOx, SO2, and CO2 are reduced by 20-40% in these cases. NOx emissions, which are a concern as a precursor of ground-level ozone, are relatively high and consistent across scenarios during summer, when peak electricity loads occur and wind resources in the region are comparatively weak. Accounting for the difference in start-up versus stabilized NOx emissions rates for natural gas plants had little impact on region-wide emissions estimates due to the dominant contribution from coal-fired plants, but would be more important in the vicinity of the natural gas units.« less

Coordination and Control of Flexible Building Loads for Renewable Integration; Demonstrations using VOLTTRON

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

Hao, He; Liu, Guopeng; Huang, Sen

Renewable energy resources such as wind and solar power have a high degree of uncertainty. Large-scale integration of these variable generation sources into the grid is a big challenge for power system operators. Buildings, in which we live and work, consume about 75% of the total electricity in the United States. They also have a large capacity of power flexibility due to their massive thermal capacitance. Therefore, they present a great opportunity to help the grid to manage power balance. In this report, we study coordination and control of flexible building loads for renewable integration. We first present the motivationmore » and background, and conduct a literature review on building-to-grid integration. We also compile a catalog of flexible building loads that have great potential for renewable integration, and discuss their characteristics. We next collect solar generation data from a photovoltaic panel on Pacific Northwest National Laboratory campus, and conduct data analysis to study their characteristics. We find that solar generation output has a strong uncertainty, and the uncertainty occurs at almost all time scales. Additional data from other sources are also used to verify our study. We propose two transactive coordination strategies to manage flexible building loads for renewable integration. We prove the theories that support the two transactive coordination strategies and discuss their pros and cons. In this report, we select three types of flexible building loads—air-handling unit, rooftop unit, and a population of WHs—for which we demonstrate control of the flexible load to track a dispatch signal (e.g., renewable generation fluctuation) using experiment, simulation, or hardware-in-the-loop study. More specifically, we present the system description, model identification, controller design, test bed setup, and experiment results for each demonstration. We show that coordination and control of flexible loads has a great potential to integrate variable generation sources. The flexible loads can successfully track a power dispatch signal from the coordinator, while having little impact on the quality of service to the end-users.« less

Modernization of dump truck onboard system

NASA Astrophysics Data System (ADS)

Semenov, M. A.; Bolshunova, O. M.; Korzhev, A. A.; Kamyshyan, A. M.

2017-10-01

The review of the only automated dispatch system for the career dump trucks, which is presented in the domestic market, was made. A method for upgrading the loading control system and technological weighing process of the career dump was proposed. The cargo weight during loading is determined by the gas pressure in the suspension cylinders at the time of the oscillation ending and at the start of the vibration smoothing process; the smoothing speed correction is performed. The error of the cargo weighting is 2.5-3%, and of the technological weighing process during driving - 1%, which corresponds to the error level of the steady-state weighting means.

Short run effects of a price on carbon dioxide emissions from U.S. electric generators.

PubMed

Newcomer, Adam; Blumsack, Seth A; Apt, Jay; Lave, Lester B; Morgan, M Granger

2008-05-01

The price of delivered electricity will rise if generators have to pay for carbon dioxide emissions through an implicit or explicit mechanism. There are two main effects that a substantial price on CO2 emissions would have in the short run (before the generation fleet changes significantly). First, consumers would react to increased price by buying less, described by their price elasticity of demand. Second, a price on CO2 emissions would change the order in which existing generators are economically dispatched, depending on their carbon dioxide emissions and marginal fuel prices. Both the price increase and dispatch changes depend on the mix of generation technologies and fuels in the region available for dispatch, although the consumer response to higher prices is the dominant effect. We estimate that the instantaneous imposition of a price of $35 per metric ton on CO2 emissions would lead to a 10% reduction in CO2 emissions in PJM and MISO at a price elasticity of -0.1. Reductions in ERCOT would be about one-third as large. Thus, a price on CO2 emissions that has been shown in earlier workto stimulate investment in new generation technology also provides significant CO2 reductions before new technology is deployed at large scale.

Development of a concentrating solar power system using fluidized-bed technology for thermal energy conversion and solid particles for thermal energy storage

DOE PAGES

Ma, Z.; Mehos, M.; Glatzmaier, G.; ...

2015-05-01

Concentrating solar power (CSP) is an effective way to convert solar energy into electricity with an economic energy-storage capability for grid-scale, dispatchable renewable power generation. However, CSP plants need to reduce costs to be competitive with other power generation methods. Two ways to reduce CSP cost are to increase solar-to-electric efficiency by supporting a high-efficiency power conversion system, and to use low-cost materials in the system. The current nitrate-based molten-salt systems have limited potential for cost reduction and improved power-conversion efficiency with high operating temperatures. Even with significant improvements in operating performance, these systems face challenges in satisfying the costmore » and performance targets. This paper introduces a novel CSP system with high-temperature capability that can be integrated into a high-efficiency CSP plant and that meets the low-cost, high-performance CSP targets. Unlike a conventional salt-based CSP plant, this design uses gas/solid, two-phase flow as the heat-transfer fluid (HTF); separated solid particles as storage media; and stable, inexpensive materials for the high-temperature receiver and energy storage containment. We highlight the economic and performance benefits of this innovative CSP system design, which has thermal energy storage capability for base-load power generation.« less

The new Venezuelan national control center

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

Beluche, C.M.

1984-07-01

This paper describes the actual status of the Venezuelan Electric Power System, the different operational areas involved, and finally the Interconnected System. Due to the development in the Power System, and in order to perform a more reliable and economic operation, it was established the need to implement a new supervisory system, for the Interconnected System Control Center. Also is described the system for the new control center for Oficina de Operacion de Sistemas Interconectados (OPSIS). OPSIS will monitor the Bulk Transmission Network (BTN), and will exchange information and control with the Regional Dispatch Centers through the computer network. Themore » Regional Dispatch Center (RDC) shall have the responsibility to accomplish the control order. The Bulk Transmissions System consists of that portion of the system from 800 KV to 230 KV. A total of six RDCs will be included in the system.« less

Model Predictive Control-based Optimal Coordination of Distributed Energy Resources

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

Mayhorn, Ebony T.; Kalsi, Karanjit; Lian, Jianming

2013-01-07

Distributed energy resources, such as renewable energy resources (wind, solar), energy storage and demand response, can be used to complement conventional generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging, especially in isolated systems. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation performance. The goals of the optimization problem are to minimize fuel costs and maximize the utilization of wind while considering equipment life of generators and energy storage. Model predictive controlmore » (MPC) is used to solve a look-ahead dispatch optimization problem and the performance is compared to an open loop look-ahead dispatch problem. Simulation studies are performed to demonstrate the efficacy of the closed loop MPC in compensating for uncertainties and variability caused in the system.« less

Model Predictive Control-based Optimal Coordination of Distributed Energy Resources

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

Mayhorn, Ebony T.; Kalsi, Karanjit; Lian, Jianming

2013-04-03

Distributed energy resources, such as renewable energy resources (wind, solar), energy storage and demand response, can be used to complement conventional generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging, especially in isolated systems. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation performance. The goals of the optimization problem are to minimize fuel costs and maximize the utilization of wind while considering equipment life of generators and energy storage. Model predictive controlmore » (MPC) is used to solve a look-ahead dispatch optimization problem and the performance is compared to an open loop look-ahead dispatch problem. Simulation studies are performed to demonstrate the efficacy of the closed loop MPC in compensating for uncertainties and variability caused in the system.« less

Stochastic representation of fire behavior in a wildland fire protection planning model for California.

Treesearch

J. Keith Gilless; Jeremy S. Fried

1998-01-01

A fire behavior module was developed for the California Fire Economics Simulator version 2 (CFES2), a stochastic simulation model of initial attack on wildland fire used by the California Department of Forestry and Fire Protection. Fire rate of spread (ROS) and fire dispatch level (FDL) for simulated fires "occurring" on the same day are determined by making...

A Hybrid Demand Response Simulator Version 1.0

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

2012-05-02

A hybrid demand response simulator is developed to test different control algorithms for centralized and distributed demand response (DR) programs in a small distribution power grid. The HDRS is designed to model a wide variety of DR services such as peak having, load shifting, arbitrage, spinning reserves, load following, regulation, emergency load shedding, etc. The HDRS does not model the dynamic behaviors of the loads, rather, it simulates the load scheduling and dispatch process. The load models include TCAs (water heaters, air conditioners, refrigerators, freezers, etc) and non-TCAs (lighting, washer, dishwasher, etc.) The ambient temperature changes, thermal resistance, capacitance, andmore » the unit control logics can be modeled for TCA loads. The use patterns of the non-TCA can be modeled by probability of use and probabilistic durations. Some of the communication network characteristics, such as delays and errors, can also be modeled. Most importantly, because the simulator is modular and greatly simplified the thermal models for TCA loads, it is very easy and fast to be used to test and validate different control algorithms in a simulated environment.« less

The United States Strategic Bombing Surveys, (European War) (Pacific War)

DTIC Science & Technology

1987-10-01

traffic between the Ruhr and points on the north coast and in central Germany . By October 14, traffic on the Rhine had been interdicted by a bomb that...the National Load Dispatcher, and secret minutes of the Central Planning Committee . Fears that their extreme vulnerability would be discovered were...fighting and other defensive resources of surrounding communities and, as a final resort, on mobile reserves deployed by the central government through

[Dispatchers' impressions and actual quality of cardiopulmonary resuscitation during telephone-assisted bystander cardiopulmonary resuscitation: a pooled analysis of 94 simulated, manikin-based scenarios].

PubMed

van Tulder, Raphael; Roth, Dominik; Laggner, Roberta; Krammel, Mario; Schriefl, Christoph; Kienbacher, Calvin; Novosad, Heinz; Chwojka, Constantin Christof; Sterz, Fritz; Havel, Christof; Schreiber, Wolfgang; Herkner, Harald

2017-02-01

The quality of telephone-assisted cardiopulmonary resuscitation (CPR) needs improvement. This study investigates whether a dispatchers' perception is an adequate measure of the actual quality of CPR provided by laypersons. Individual participant data from 3 randomized simulation trials, with identical methodology but different interventions, were combined for this analysis. Professional dispatchers gave telephone assistance to laypersons, who each provided 10 minutes of CPR on a manikin. Dispatchers were requested to classify the quality of providers' CPR as adequate or inadequate. Based on actual readings from manikins we classified providers' performance as adequate at 5-6 cm for depth and 100-120 compressions per minute (cpm) for rate. We calculated metrics of dispatcher accuracy. Six dispatchers rated the performance of 94 laypersons (38 women [42%]) with a mean (SD) age of 37 (14) years. In 905 analyzed minutes of telephone-assisted CPR, the mean compression depth and rate was 41 (13) mm and 98 (24) cpm, respectively. Analysis of dispatchers' diagnostic test accuracy for adequate compression depth yielded a sensitivity of 65% (95 CI 36%-95%) and specificity of 42% (95% CI, 32%-53%). Analysis of their assessment of adequate compression rate yielded a sensitivity of 75% (95% CI, 64%-86%) and specificity of 42% (95% CI, 32%-52%). Although dispatchers always underestimated the actual values of CPR parameters, the female dispatchers evaluations were less inaccurate than the evaluations of make dispatchers; the dispatchers overall (males and females together) underestimated the adequacy of female laypersons' CPR performance to a greater degree than female dispatchers did. The ability of dispatchers to estimate the quality of telephone-assisted CPR is limited. Dispatchers estimates of CPR adequacy needs to be studied further in order to find ways that telephone-assisted CPR might be improved.

The Mathematics of Dispatchability, Revisited

NASA Technical Reports Server (NTRS)

Morris, Paul

2016-01-01

Dispatchability is an important property for the efficient execution of temporal plans where the temporal constraints are represented as a Simple Temporal Network (STN). It has been shown that every STN may be reformulated as a dispatchable STN, and dispatchability ensures that the temporal constraints need only be satisfied locally during execution. Recently, it has also been shown that Simple Temporal Networks with Uncertainty, augmented with wait edges, are Dynamically Controllable provided every projection is dispatchable. Thus, dispatchability has considerable theoretical as well as practical significance. One thing that hampers further work in this area is the underdeveloped theory. Moreover, the existing foundation is inadequate in certain respects. In this paper, we develop a new mathematical theory of dispatchability and its relationship to execution. We also provide several characterizations of dispatchability, including characterizations in terms of the structural properties of the STN graph. This facilitates the potential application of the theory to other areas.

The Mathematics of Dispatchability Revisited

NASA Technical Reports Server (NTRS)

Morris, Paul

2016-01-01

Dispatchability is an important property for the efficient execution of temporal plans where the temporal constraints are represented as a Simple Temporal Network (STN). It has been shown that every STN may be reformulated as a dispatchable STN, and dispatchability ensures that the temporal constraints need only be satisfied locally during execution. Recently it has also been shown that Simple Temporal Networks with Uncertainty, augmented with wait edges, are Dynamically Controllable provided every projection is dispatchable. Thus, the dispatchability property has both theoretical and practical interest. One thing that hampers further work in this area is the underdeveloped theory. The existing definitions are expressed in terms of algorithms, and are less suitable for mathematical proofs. In this paper, we develop a new formal theory of dispatchability in terms of execution sequences. We exploit this to prove a characterization of dispatchability involving the structural properties of the STN graph. This facilitates the potential application of the theory to uncertainty reasoning.

Implications of near-term coal power plant retirement for SO2 and NOX and life cycle GHG emissions.

PubMed

Venkatesh, Aranya; Jaramillo, Paulina; Griffin, W Michael; Matthews, H Scott

2012-09-18

Regulations monitoring SO(2), NO(X), mercury, and other metal emissions in the U.S. will likely result in coal plant retirement in the near-term. Life cycle assessment studies have previously estimated the environmental benefits of displacing coal with natural gas for electricity generation, by comparing systems that consist of individual natural gas and coal power plants. However, such system comparisons may not be appropriate to analyze impacts of coal plant retirement in existing power fleets. To meet this limitation, simplified economic dispatch models for PJM, MISO, and ERCOT regions are developed in this study to examine changes in regional power plant dispatch that occur when coal power plants are retired. These models estimate the order in which existing power plants are dispatched to meet electricity demand based on short-run marginal costs, with cheaper plants being dispatched first. Five scenarios of coal plant retirement are considered: retiring top CO(2) emitters, top NO(X) emitters, top SO(2) emitters, small and inefficient plants, and old and inefficient plants. Changes in fuel use, life cycle greenhouse gas emissions (including uncertainty), and SO(2) and NO(X) emissions are estimated. Life cycle GHG emissions were found to decrease by less than 4% in almost all scenarios modeled. In addition, changes in marginal damage costs due to SO(2), and NO(X) emissions are estimated using the county level marginal damage costs reported in the Air Pollution Emissions Experiments and Policy (APEEP) model, which are a proxy for measuring regional impacts of SO(2) and NO(X) emissions. Results suggest that location specific parameters should be considered within environmental policy frameworks targeting coal plant retirement, to account for regional variability in the benefits of reducing the impact of SO(2) and NO(X) emissions.

14 CFR 65.67 - Aircraft dispatcher certification courses: Personnel.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Aircraft dispatcher certification courses....67 Aircraft dispatcher certification courses: Personnel. (a) Each applicant for an aircraft dispatcher certification course must meet the following personnel requirements: (1) Each applicant must have...

14 CFR 65.67 - Aircraft dispatcher certification courses: Personnel.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Aircraft dispatcher certification courses....67 Aircraft dispatcher certification courses: Personnel. (a) Each applicant for an aircraft dispatcher certification course must meet the following personnel requirements: (1) Each applicant must have...

14 CFR 65.67 - Aircraft dispatcher certification courses: Personnel.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft dispatcher certification courses....67 Aircraft dispatcher certification courses: Personnel. (a) Each applicant for an aircraft dispatcher certification course must meet the following personnel requirements: (1) Each applicant must have...

14 CFR 65.67 - Aircraft dispatcher certification courses: Personnel.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aircraft dispatcher certification courses....67 Aircraft dispatcher certification courses: Personnel. (a) Each applicant for an aircraft dispatcher certification course must meet the following personnel requirements: (1) Each applicant must have...

14 CFR 65.67 - Aircraft dispatcher certification courses: Personnel.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Aircraft dispatcher certification courses....67 Aircraft dispatcher certification courses: Personnel. (a) Each applicant for an aircraft dispatcher certification course must meet the following personnel requirements: (1) Each applicant must have...

Emissions impacts and benefits of plug-in hybrid electric vehicles and vehicle-to-grid services

DOE PAGES

Sioshansi, Ramteen; Denholm, Paul

2009-01-22

Plug-in hybrid electric vehicles (PHEVs) have been promoted as a potential technology to reduce emissions of greenhouse gases and other pollutants by using electricity instead of petroleum, and by improving electric system efficiency by providing vehicle-to-grid (V2G) services. We use an electric power system model to explicitly evaluate the change in generator dispatches resulting from PHEV deployment in the Texas grid, and apply fixed and non-parametric estimates of generator emissions rates, to estimate the resulting changes in generation emissions. Here, we find that by using the flexibility of when vehicles may be charged, generator efficiency can be increased substantially. Bymore » changing generator dispatch, a PHEV fleet of up to 15% of light-duty vehicles can actually decrease net generator NO x emissions during the ozone season, despite the additional charging load. By adding V2G services, such as spinning reserves and energy storage, CO 2, SO 2, and NO x emissions can be reduced even further.« less

Dispatchable Renewable Energy Model for Microgrid Power System

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

Chiou, Fred; Gentle, Jake P.; McJunkin, Timothy R.

2017-04-01

Over the years, many research projects have been performed and focused on finding out the effective ways to balance the power demands and supply on the utility grid. The causes of the imbalance could be the increasing demands from the end users, the loss of power generation (generators down), faults on the transmission lines, power tripped due to overload, and weather conditions, etc. An efficient Load Frequency Control (LFC) can assure the desired electricity quality provided to the residential, commercial and industrial end users. A simulation model is built in this project to investigate the contribution of the modeling ofmore » dispatchable energy such as solar energy, wind power, hydro power and energy storage to the balance of the microgrid power system. An analysis of simplified feedback control system with proportional, integral, and derivative (PID) controller was performed. The purpose of this research is to investigate a simulation model that achieves certain degree of the resilient control for the microgrid.« less

Emissions impacts and benefits of plug-in hybrid electric vehicles and vehicle-to-grid services.

PubMed

Sioshansi, Ramteen; Denholm, Paul

2009-02-15

Plug-in hybrid electric vehicles (PHEVs) have been promoted as a potential technology to reduce emissions of greenhouse gases and other pollutants by using electricity instead of petroleum, and byimproving electric system efficiency by providing vehicle-to-grid (V2G) services. We use an electric power system model to explicitly evaluate the change in generator dispatches resulting from PHEV deployment in the Texas grid, and apply fixed and non-parametric estimates of generator emissions rates, to estimate the resulting changes in generation emissions. We find that by using the flexibility of when vehicles may be charged, generator efficiency can be increased substantially. By changing generator dispatch, a PHEVfleet of up to 15% of light-duty vehicles can actually decrease net generator NOx emissions during the ozone season, despite the additional charging load. By adding V2G services, such as spinning reserves and energy storage, CO2, SO2, and NOx emissions can be reduced even further.

Ancillary-service costs for 12 US electric utilities

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

Kirby, B.; Hirst, E.

1996-03-01

Ancillary services are those functions performed by electrical generating, transmission, system-control, and distribution-system equipment and people to support the basic services of generating capacity, energy supply, and power delivery. The Federal Energy Regulatory Commission defined ancillary services as ``those services necessary to support the transmission of electric power from seller to purchaser given the obligations of control areas and transmitting utilities within those control areas to maintain reliable operations of the interconnected transmission system.`` FERC divided these services into three categories: ``actions taken to effect the transaction (such as scheduling and dispatching services) , services that are necessary to maintainmore » the integrity of the transmission system [and] services needed to correct for the effects associated with undertaking a transaction.`` In March 1995, FERC published a proposed rule to ensure open and comparable access to transmission networks throughout the country. The rule defined six ancillary services and developed pro forma tariffs for these services: scheduling and dispatch, load following, system protection, energy imbalance, loss compensation, and reactive power/voltage control.« less

Modelling Concentrating Solar Power with Thermal Energy Storage for Integration Studies (Presentation)

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

Hummon, M.; Jorgenson, J.; Denholm, P.

2013-10-01

Concentrating solar power with thermal energy storage (CSP-TES) can provide multiple benefits to the grid, including low marginal cost energy and the ability to levelize load, provide operating reserves, and provide firm capacity. It is challenging to properly value the integration of CSP because of the complicated nature of this technology. Unlike completely dispatchable fossil sources, CSP is a limited energy resource, depending on the hourly and daily supply of solar energy. To optimize the use of this limited energy, CSP-TES must be implemented in a production cost model with multiple decision variables for the operation of the CSP-TES plant.more » We develop and implement a CSP-TES plant in a production cost model that accurately characterizes the three main components of the plant: solar field, storage tank, and power block. We show the effect of various modelling simplifications on the value of CSP, including: scheduled versus optimized dispatch from the storage tank and energy-only operation versus co-optimization with ancillary services.« less

Modelling Concentrating Solar Power with Thermal Energy Storage for Integration Studies: Preprint

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

Hummon, M.; Denholm, P.; Jorgenson, J.

2013-10-01

Concentrating solar power with thermal energy storage (CSP-TES) can provide multiple benefits to the grid, including low marginal cost energy and the ability to levelize load, provide operating reserves, and provide firm capacity. It is challenging to properly value the integration of CSP because of the complicated nature of this technology. Unlike completely dispatchable fossil sources, CSP is a limited energy resource, depending on the hourly and daily supply of solar energy. To optimize the use of this limited energy, CSP-TES must be implemented in a production cost model with multiple decision variables for the operation of the CSP-TES plant.more » We develop and implement a CSP-TES plant in a production cost model that accurately characterizes the three main components of the plant: solar field, storage tank, and power block. We show the effect of various modelling simplifications on the value of CSP, including: scheduled versus optimized dispatch from the storage tank and energy-only operation versus co-optimization with ancillary services.« less

Power Distribution Analysis For Electrical Usage In Province Area Using Olap (Online Analytical Processing)

NASA Astrophysics Data System (ADS)

Samsinar, Riza; Suseno, Jatmiko Endro; Widodo, Catur Edi

2018-02-01

The distribution network is the closest power grid to the customer Electric service providers such as PT. PLN. The dispatching center of power grid companies is also the data center of the power grid where gathers great amount of operating information. The valuable information contained in these data means a lot for power grid operating management. The technique of data warehousing online analytical processing has been used to manage and analysis the great capacity of data. Specific methods for online analytics information systems resulting from data warehouse processing with OLAP are chart and query reporting. The information in the form of chart reporting consists of the load distribution chart based on the repetition of time, distribution chart on the area, the substation region chart and the electric load usage chart. The results of the OLAP process show the development of electric load distribution, as well as the analysis of information on the load of electric power consumption and become an alternative in presenting information related to peak load.

Impacts of temperature change on ambulance dispatches and seasonal effect modification.

PubMed

Cheng, Jian; Xu, Zhiwei; Zhao, Desheng; Xie, Mingyu; Yang, Huihui; Wen, Liying; Li, Kesheng; Su, Hong

2016-12-01

Ambulance dispatch is a proxy of acute health outcomes, and growing epidemiological evidence documented its relation to extreme temperature events. Research, however, on short-term temperature change and ambulance dispatches is scarce. We aimed to investigate the effect of short-term temperature change on ambulance dispatches and potential modification by season. Daily data on ambulance dispatch and weather factors were collected in Huainan, a Chinese inland city from December 2011 through December 2013. A Poison generalized linear regression model combined with distributed lag nonlinear model was constructed to examine the association of temperature change between neighboring days (TCN) with ambulance dispatches. The effect modification by season was also examined. There were 48,700 ambulance attendances during the study period. A statistically significant association of TCN with ambulance dispatches was observed. Temperature rise between neighboring days (TCN > 0) was associated with elevated adverse risk of ambulance dispatches, and the effects appeared to be acute (lag0, on the current day) and could last for at least a week, while temperature drop between neighboring days (TCN < 0) had a protective effect. For a 1 °C increase of TCN at lag0 and lag06 (on the 7-day moving average), the risk of ambulance dispatches increased by 2 % (95 % CI 1-3 %) and 7 (95 % CI 1-13 %), respectively. Extreme TCN increase (95th percentile, 3.3 °C vs. 0 °C) at lag0 and lag05 was accompanied by 6 (95 % CI 3-8 %) and 27 % (95 % CI 12-44 %) increase in ambulance dispatches. Ambulance dispatches were more vulnerable to extremely great temperature rise in summer and autumn. TCN was adopted for the first time to quantify the impact of short-term temperature change on ambulance dispatches. Temperature drop between neighboring days (TCN < 0) had a protective effect on ambulance dispatches, while temperature rise between neighboring days (TCN > 0) could acutely trigger the increase in ambulance dispatches, and TCN effect differs by season.

Electricity from fossil fuels without CO2 emissions: assessing the costs of carbon dioxide capture and sequestration in U.S. electricity markets.

PubMed

Johnson, T L; Keith, D W

2001-10-01

The decoupling of fossil-fueled electricity production from atmospheric CO2 emissions via CO2 capture and sequestration (CCS) is increasingly regarded as an important means of mitigating climate change at a reasonable cost. Engineering analyses of CO2 mitigation typically compare the cost of electricity for a base generation technology to that for a similar plant with CO2 capture and then compute the carbon emissions mitigated per unit of cost. It can be hard to interpret mitigation cost estimates from this plant-level approach when a consistent base technology cannot be identified. In addition, neither engineering analyses nor general equilibrium models can capture the economics of plant dispatch. A realistic assessment of the costs of carbon sequestration as an emissions abatement strategy in the electric sector therefore requires a systems-level analysis. We discuss various frameworks for computing mitigation costs and introduce a simplified model of electric sector planning. Results from a "bottom-up" engineering-economic analysis for a representative U.S. North American Electric Reliability Council (NERC) region illustrate how the penetration of CCS technologies and the dispatch of generating units vary with the price of carbon emissions and thereby determine the relationship between mitigation cost and emissions reduction.

Electricity from Fossil Fuels without CO2 Emissions: Assessing the Costs of Carbon Dioxide Capture and Sequestration in U.S. Electricity Markets.

PubMed

Johnson, Timothy L; Keith, David W

2001-10-01

The decoupling of fossil-fueled electricity production from atmospheric CO 2 emissions via CO 2 capture and sequestration (CCS) is increasingly regarded as an important means of mitigating climate change at a reasonable cost. Engineering analyses of CO 2 mitigation typically compare the cost of electricity for a base generation technology to that for a similar plant with CO 2 capture and then compute the carbon emissions mitigated per unit of cost. It can be hard to interpret mitigation cost estimates from this plant-level approach when a consistent base technology cannot be identified. In addition, neither engineering analyses nor general equilibrium models can capture the economics of plant dispatch. A realistic assessment of the costs of carbon sequestration as an emissions abatement strategy in the electric sector therefore requires a systems-level analysis. We discuss various frameworks for computing mitigation costs and introduce a simplified model of electric sector planning. Results from a "bottom-up" engineering-economic analysis for a representative U.S. North American Electric Reliability Council (NERC) region illustrate how the penetration of CCS technologies and the dispatch of generating units vary with the price of carbon emissions and thereby determine the relationship between mitigation cost and emissions reduction.

Wind-Friendly Flexible Ramping Product Design in Multi-Timescale Power System Operations

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

Cui, Mingjian; Zhang, Jie; Wu, Hongyu

With increasing wind power penetration in the electricity grid, system operators are recognizing the need for additional flexibility, and some are implementing new ramping products as a type of ancillary service. However, wind is generally thought of as causing the need for ramping services, not as being a potential source for the service. In this paper, a multi-timescale unit commitment and economic dispatch model is developed to consider the wind power ramping product (WPRP). An optimized swinging door algorithm with dynamic programming is applied to identify and forecast wind power ramps (WPRs). Designed as positive characteristics of WPRs, the WPRPmore » is then integrated into the multi-timescale dispatch model that considers new objective functions, ramping capacity limits, active power limits, and flexible ramping requirements. Numerical simulations on the modified IEEE 118-bus system show the potential effectiveness of WPRP in increasing the economic efficiency of power system operations with high levels of wind power penetration. It is found that WPRP not only reduces the production cost by using less ramping reserves scheduled by conventional generators, but also possibly enhances the reliability of power system operations. Moreover, wind power forecasts play an important role in providing high-quality WPRP service.« less

Cost analysis of an electricity supply chain using modification of price based dynamic economic dispatch in wheeling transaction scheme

NASA Astrophysics Data System (ADS)

Wahyuda; Santosa, Budi; Rusdiansyah, Ahmad

2018-04-01

Deregulation of the electricity market requires coordination between parties to synchronize the optimization on the production side (power station) and the transport side (transmission). Electricity supply chain presented in this article is designed to facilitate the coordination between the parties. Generally, the production side is optimized with price based dynamic economic dispatch (PBDED) model, while the transmission side is optimized with Multi-echelon distribution model. Both sides optimization are done separately. This article proposes a joint model of PBDED and multi-echelon distribution for the combined optimization of production and transmission. This combined optimization is important because changes in electricity demand on the customer side will cause changes to the production side that automatically also alter the transmission path. The transmission will cause two cost components. First, the cost of losses. Second, the cost of using the transmission network (wheeling transaction). Costs due to losses are calculated based on ohmic losses, while the cost of using transmission lines using the MW - mile method. As a result, this method is able to provide best allocation analysis for electrical transactions, as well as emission levels in power generation and cost analysis. As for the calculation of transmission costs, the Reverse MW-mile method produces a cheaper cost than the Absolute MW-mile method

A price-responsive dispatching strategy for Vehicle-to-Grid: An economic evaluation applied to the case of Singapore

NASA Astrophysics Data System (ADS)

Pelzer, Dominik; Ciechanowicz, David; Aydt, Heiko; Knoll, Alois

2014-06-01

Employing electric vehicles as short-term energy storage could improve power system stability and at the same time create a new income source for vehicle owners. In this paper, the economic viability of this concept referred to as Vehicle-to-Grid is investigated. For this purpose, a price-responsive charging and dispatching strategy built upon temporally resolved electricity market data is presented. This concept allows vehicle owners to maximize returns by restricting market participation to profitable time periods. As a case study, this strategy is then applied using the example of Singapore. It is shown that an annual loss of S 1000 resulting from a non-price-responsive strategy as employed in previous works can be turned into a S 130 profit by applying the price-responsive approach. In addition to this scenario, realistic mobility patterns which restrict the temporal availability of vehicles are considered. In this case, profits in the range of S 21-S 121 are achievable. Returns in this order of magnitude are not expected to make Vehicle-to-Grid a viable business case, sensitivity analyses, however, show that improved technical parameters could increase profitability. It is further assumed that employing the price-responsive strategy to other national markets may yield significantly greater returns.

A Game Changer: Electrifying Remote Communities by Using Isolated Microgrids

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

Lu, Xiaonan; Wang, Jianhui

Microgrids, as self-contained entities, are of increasing interest in modern electric grids. Microgrids provide a sustainable solution to aggregate distributed energy resources (DERs) [e.g., photovoltaics (PVs), wind turbines], energy storage, and loads in a localized manner, especially in distribution systems. As a controllable unit, a microgrid can manage and balance the source and load power inside it to ensure stable and reliable operation. Moreover, through coordination with upper-level control systems, it can be dispatched and respond to the control commands issued by the central controller in the distribution system-in other words, a system that is effectively a distribution management systemmore » (DMS).« less

Dispatcher Recognition of Stroke Using the National Academy Medical Priority Dispatch System

PubMed Central

Buck, Brian H; Starkman, Sidney; Eckstein, Marc; Kidwell, Chelsea S; Haines, Jill; Huang, Rainy; Colby, Daniel; Saver, Jeffrey L

2009-01-01

Background Emergency Medical Dispatchers (EMDs) play an important role in optimizing stroke care if they are able to accurately identify calls regarding acute cerebrovascular disease. This study was undertaken to assess the diagnostic accuracy of the current national protocol guiding dispatcher questioning of 911 callers to identify stroke, QA Guide v 11.1 of the National Academy Medical Priority Dispatch System (MPDS). Methods We identified all Los Angeles Fire Department paramedic transports of patients to UCLA Medical Center during the 12 month period from January to December 2005 in a prospectively maintained database. Dispatcher-assigned MPDS codes for each of these patient transports were abstracted from the paramedic run sheets and compared to final hospital discharge diagnosis. Results Among 3474 transported patients, 96 (2.8%) had a final diagnosis of stroke or transient ischemic attack. Dispatchers assigned a code of potential stroke to 44.8% of patients with a final discharge diagnosis of stroke or TIA. Dispatcher identification of stroke showed a sensitivity of 0.41, specificity of 0.96, positive predictive value of 0.45, and negative predictive value of 0.95. Conclusions Dispatcher recognition of stroke calls using the widely employed MPDS algorithm is suboptimal, with failure to identify more than half of stroke patients as likely stroke. Revisions to the current national dispatcher structured interview and complaint identification algorithm for stroke may facilitate more accurate recognition of stroke by EMDs. PMID:19390065

A Hybrid Multilevel Storage Architecture for Electric Power Dispatching Big Data

NASA Astrophysics Data System (ADS)

Yan, Hu; Huang, Bibin; Hong, Bowen; Hu, Jing

2017-10-01

Electric power dispatching is the center of the whole power system. In the long run time, the power dispatching center has accumulated a large amount of data. These data are now stored in different power professional systems and form lots of information isolated islands. Integrating these data and do comprehensive analysis can greatly improve the intelligent level of power dispatching. In this paper, a hybrid multilevel storage architecture for electrical power dispatching big data is proposed. It introduces relational database and NoSQL database to establish a power grid panoramic data center, effectively meet power dispatching big data storage needs, including the unified storage of structured and unstructured data fast access of massive real-time data, data version management and so on. It can be solid foundation for follow-up depth analysis of power dispatching big data.

Hybrid Geo-Energy Systems for Energy Storage and Dispatchable Renewable and Low-Carbon Electricity

NASA Astrophysics Data System (ADS)

Buscheck, Thomas; Bielicki, Jeffrey; Ogland-Hand, Jonathan; Hao, Yue; Sun, Yunwei; Randolph, Jimmy; Saar, Martin

2015-04-01

Three primary challenges for energy systems are to (1) reduce the amount of carbon dioxide (CO2) being emitted to the atmosphere, (2) increase the penetration of renewable energy technologies, and (3) reduce the water intensity of energy production. Integrating variable renewable energy sources (wind, sunlight) into electric grids requires advances in energy storage approaches, which are currently expensive, and tend to have limited capacity and/or geographic deployment potential. Our approach uses CO2, that would otherwise be emitted to the atmosphere, to generate electricity from geothermal resources, to store excess energy from variable (wind, solar photovoltaic) and thermal (nuclear, fossil, concentrated solar power) sources, and to thus enable increased penetration of renewable energy technologies. We take advantage of the enormous fluid and thermal storage capacity of the subsurface to harvest, store, and dispatch energy. Our approach uses permeable geologic formations that are vertically bounded by impermeable layers to constrain pressure and the migration of buoyant CO2 and heated brine. Supercritical CO2 captured from fossil power plants is injected into these formations as a cushion gas to store pressure (bulk energy), provide an heat efficient extraction fluid for efficient power conversion in Brayton Cycle turbines, and generate artesian flow of brine -- which can be used to cool power plants and/or pre-heated (thermal storage) prior to re-injection. Concentric rings of injection and production wells create a hydraulic divide to store pressure, CO2, and thermal energy. The system is pressurized and/or heated when power supply exceeds demand and depressurized when demand exceeds supply. Time-shifting the parasitic loads from pressurizing and injecting brine and CO2 provides bulk energy storage over days to months, whereas time-shifting thermal-energy supply provides dispatchable power and addresses seasonal mismatches between supply and demand. These conditions enable efficient fluid recirculation, heat extraction, power conversion, and add operational flexibility to dispatch electricity. Overall, the system can (a) levelize concentrating solar power, (b) mitigate variability of wind and solar power, (c) reduce water and carbon intensity of energy systems, (d) avoid wasting or curtailing high-capital cost, low-carbon energy resources and (e) allow low-carbon, base-load power to operate at full capacity. This work was performed under the auspices of the U.S. DOE by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, and has been funded by the U.S. National Science Foundation Sustainable Energy Pathways Program (1230691) and the U.S. Department of Energy Geothermal Technologies Office (DE-FOA-0000336).

Air Quality Improvements of Increased Integration of Renewables: Solar Photovoltaics Penetration Scenarios

NASA Astrophysics Data System (ADS)

Duran, P.; Holloway, T.; Brinkman, G.; Denholm, P.; Littlefield, C. M.

2011-12-01

Solar photovoltaics (PV) are an attractive technology because they can be locally deployed and tend to yield high production during periods of peak electric demand. These characteristics can reduce the need for conventional large-scale electricity generation, thereby reducing emissions of criteria air pollutants (CAPs) and improving ambient air quality with regard to such pollutants as nitrogen oxides, sulfur oxides and fine particulates. Such effects depend on the local climate, time-of-day emissions, available solar resources, the structure of the electric grid, and existing electricity production among other factors. This study examines the air quality impacts of distributed PV across the United States Eastern Interconnection. In order to accurately model the air quality impact of distributed PV in space and time, we used the National Renewable Energy Lab's (NREL) Regional Energy Deployment System (ReEDS) model to form three unique PV penetration scenarios in which new PV construction is distributed spatially based upon economic drivers and natural solar resources. Those scenarios are 2006 Eastern Interconnection business as usual, 10% PV penetration, and 20% PV penetration. With the GridView (ABB, Inc) dispatch model, we used historical load data from 2006 to model electricity production and distribution for each of the three scenarios. Solar PV electric output was estimated using historical weather data from 2006. To bridge the gap between dispatch and air quality modeling, we will create emission profiles for electricity generating units (EGUs) in the Eastern Interconnection from historical Continuous Emissions Monitoring System (CEMS) data. Via those emissions profiles, we will create hourly emission data for EGUs in the Eastern Interconnect for each scenario during 2006. Those data will be incorporated in the Community Multi-scale Air Quality (CMAQ) model using the Sparse Matrix Operator Kernel Emissions (SMOKE) model. Initial results indicate that PV penetration significantly reduces conventional peak electricity production and that, due to reduced emissions during periods of extremely active photochemistry, air quality could see benefits.

Impacts of demand response and renewable generation in electricity power market

NASA Astrophysics Data System (ADS)

Zhao, Zhechong

This thesis presents the objective of the research which is to analyze the impacts of uncertain wind power and demand response on power systems operation and power market clearing. First, in order to effectively utilize available wind generation, it is usually given the highest priority by assigning zero or negative energy bidding prices when clearing the day-ahead electric power market. However, when congestion occurs, negative wind bidding prices would aggravate locational marginal prices (LMPs) to be negative in certain locations. A load shifting model is explored to alleviate possible congestions and enhance the utilization of wind generation, by shifting proper amount of load from peak hours to off peaks. The problem is to determine proper amount of load to be shifted, for enhancing the utilization of wind generation, alleviating transmission congestions, and making LMPs to be non-negative values. The second piece of work considered the price-based demand response (DR) program which is a mechanism for electricity consumers to dynamically manage their energy consumption in response to time-varying electricity prices. It encourages consumers to reduce their energy consumption when electricity prices are high, and thereby reduce the peak electricity demand and alleviate the pressure to power systems. However, it brings additional dynamics and new challenges on the real-time supply and demand balance. Specifically, price-sensitive DR load levels are constantly changing in response to dynamic real-time electricity prices, which will impact the economic dispatch (ED) schedule and in turn affect electricity market clearing prices. This thesis adopts two methods for examining the impacts of different DR price elasticity characteristics on the stability performance: a closed-loop iterative simulation method and a non-iterative method based on the contraction mapping theorem. This thesis also analyzes the financial stability of DR load consumers, by incorporating explicit LMP formulations and consumer payment requirements into the network-constrained unit commitment (NCUC) problem. The proposed model determines the proper amount of DR loads to be shifted from peak hours to off-peaks under ISO's direct load control, for reducing the operation cost and ensuring that consumer payments of DR loads will not deteriorate significantly after load shifting. Both MINLP and MILP models are discussed, and improved formulation strategies are presented.

Handling of drug-related emergencies: an evaluation of emergency medical dispatch.

PubMed

Tonje, Lorem; Elisabeth, Saether; Lars, Wik

2009-02-01

Documenting the quality of emergency dispatch centres handling of emergency calls regarding intoxicated unconscious patients. Interview with eight emergency dispatch centre directors and a nationwide survey among 313 dispatchers in Norway were performed. In addition, a customized scoring system was used to evaluate dispatcher log recordings of real cases. The recordings were compared with information from corresponding ambulance records. Ninety-nine percent of the dispatchers stated that they used the Norwegian protocol for medical emergencies and 89% of them found it useful. The interviews, the survey, and the recordings, however, documented frequent deviation from the protocol. This instructs ambulance dispatch for any unconscious patient, but 21% stated that they would not dispatch any resource for an unconscious patient without further survey in alcohol-related cases. This was significantly more often (P<0.05) than for the narcotic, combination and prescription - drug-related cases with 4, 10 and 7%, respectively. The recordings revealed deviation from the protocol with dispatchers only determining the patients' level of consciousness and respiratory status in 64 and 70% of the cases, respectively. For 16% of the cases, the dispatcher did not ask the caller about consciousness at all, even though these patients later were found with reduced consciousness. On the basis of the interviews and the survey, cases were handled according to guidelines. The log recordings, however, disclosed deviation from the protocol. Alcohol intoxication was associated with higher rate of deviation from the protocol compared with other intoxications.

The effect of work shift configurations on emergency medical dispatch center response.

PubMed

Montassier, Emmanuel; Labady, Julien; Andre, Antoine; Potel, Gilles; Berthier, Frederic; Jenvrin, Joel; Penverne, Yann

2015-01-01

It has been proved that emergency medical dispatch centers (EMDC) save lives by promoting an appropriate allocation of emergency medical service resources. Indeed, optimal dispatcher call duration is pivotal to reduce the time gap between the time a call is placed and the delivery of medical care. However, little is known about the impact of work shift configurations (i.e., work shift duration and work shift rotation throughout the day) and dispatcher call duration. Thus, the objective of our study was to assess the effect of work shift configurations on dispatcher call duration. During a 1-year study period, we analyzed the dispatcher call durations for medical and trauma calls during the 4 different work shift rotations (day, morning, evening, and night) and during the 10-hour work shift of each dispatcher in the EMDC of Nantes. We extracted dispatcher call durations from our advanced telephone system, configured with CC Pulse + (Genesys, Alcatel Lucent), and collected them in a custom designed database (Excel, Microsoft). Afterward, we analyzed these data using linear mixed effects models. During the study period, our EMDC received 408,077 calls. Globally, the mean dispatcher call duration was 107 ± 45 seconds. Based on multivariate linear mixed effects models, the dispatcher call duration was affected by night work shift and work shift duration greater than 8 hours, increasing it by about 10 ± 1 seconds and 4 ± 1 seconds, respectively (both p < 0.001). Our study showed that there was a statistically significant difference in dispatcher call duration over work shift rotation and duration, with longer durations seen over night shifts and shifts over 8 hours. While these differences are small and may not have clinical significance, they may have implications for EMDC efficiency.

Effect and accuracy of emergency dispatch telephone guidance to bystanders in trauma: post-hoc analysis of a prospective observational study.

PubMed

Bakke, Håkon Kvåle; Steinvik, Tine; Ruud, Håkon; Wisborg, Torben

2017-03-07

Emergency medical communication centres (EMCCs) dispatch and allocate ambulance resources, and provide first-aid guidance to on-scene bystanders. We aimed to 1) evaluate whether dispatcher guidance improved bystander first aid in trauma, and 2) to evaluate whether dispatchers and on-scene emergency medical services (EMS) crews identified the same first aid measures as indicated. For 18 months, the crew on the first EMS crew responding to trauma calls used a standard form to assess bystander first aid. Audio recordings of the corresponding telephone calls from bystanders to the EMCC were reviewed. A total of 311 trauma calls were included. The on-scene EMS crew identified needs for the following first-aid measures: free airway in 26 patients, CPR in 6 patients, and hypothermia prevention in 179 patients. EMCC dispatchers advised these measures, respectively, in 16 (62%), 5 (83%), and 54 (30%) of these cases. Dispatcher guidance was not correlated with correctly performed bystander first aid. For potentially life saving first aid measures, all (20/20) callers who received dispatcher guidance attempted first aid, while only some few (4/22) of the callers who did not receive dispatcher guidance did not attempt first aid. Overall, the EMCC dispatchers had low sensitivity and specificity for correctly identifying trauma patients requiring first-aid measures. Dispatcher guidance did not significantly influence whether on-scene bystander first aid was performed correctly or attempted in this study setting, with a remarkably high willingness to perform first-aid. However, the findings for potentially lifesaving measures suggests that there may be differences that this study was unable to detect. This study found a high rate of first-aid willingness and performance, even without dispatcher prompting, and a low precision in dispatcher advice. This underlines the need for further knowledge about how to increase EMCC dispatchers' possibility to identify trauma patients in need of first aid. The correlation between EMCC-guidance and bystander first aid should be investigated in study settings with lower spontaneous first-aid rates.

Feasibility study report for distribution dispatching center project 2nd stage for the Provincial Electricity Authority (PEA), Bangkok, Thailand, June 1998. Export trade information

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

NONE

The study concerns the Provincial Electricity Authority, a state agency within the Ministry of Interior that supplies electricity to 73 of Thailand`s provinces. The primary objective of this study is to help increase the ability of the Authority to meet the rapidly increasing demand for electric power within the Kingdom of Thailand in a reliable, safe and economic manner. This is Volume 1 and it consists of the following: (1) introduction; (2) assessment; (3) conceptual design; (4) economic and financial evaluation; (5) project plan; (6) Thailand impact; (7) industry review; (8) conclusion; and appendices.

Dispatchable hydrogen production at the forecourt for electricity grid balancing

NASA Astrophysics Data System (ADS)

Rahil, Abdulla; Gammon, Rupert; Brown, Neil

2017-02-01

The rapid growth of renewable energy (RE) generation and its integration into electricity grids has been motivated by environmental issues and the depletion of fossil fuels. For the same reasons, an alternative to hydrocarbon fuels is needed for vehicles; hence the anticipated uptake of electric and fuel cell vehicles. High penetrations of RE generators with variable and intermittent output threaten to destabilise electricity networks by reducing the ability to balance electricity supply and demand. This can be greatly mitigated by the use of energy storage and demand-side response (DSR) techniques. Hydrogen production by electrolysis is a promising option for providing DSR as well as an emission-free vehicle fuel. Tariff structures can be used to incentivise the operating of electrolysers as controllable (dispatchable) loads. This paper compares the cost of hydrogen production by electrolysis at garage forecourts under both dispatchable and continuous operation, while ensuring no interruption of fuel supply to fuel cell vehicles. An optimisation algorithm is applied to investigate a hydrogen refueling station in both dispatchable and continuous operation. Three scenarios are tested to see whether a reduced off-peak electricity price could lower the cost of electrolytic hydrogen. These scenarios are: 1) "Standard Continuous", where the electrolyser is operated continuously on a standard all-day tariff of 12p/kWh; 2) "Off-peak Only", where it runs only during off-peak periods in a 2-tier tariff system at the lower price of 5p/kWh; and 3) "2-Tier Continuous", operating continuously and paying a low tariff at off- peak times and a high tariff at other times. This study uses the Libyan coastal city of Derna as a case study. The cheapest electricity cost per kg of hydrogen produced was £2.8, which occurred in Scenario 2. The next cheapest, at £5.8 - £6.3, was in Scenario 3, and the most expensive was £6.8/kg in Scenario 1.

An implementation of particle swarm optimization to evaluate optimal under-voltage load shedding in competitive electricity markets

NASA Astrophysics Data System (ADS)

Hosseini-Bioki, M. M.; Rashidinejad, M.; Abdollahi, A.

2013-11-01

Load shedding is a crucial issue in power systems especially under restructured electricity environment. Market-driven load shedding in reregulated power systems associated with security as well as reliability is investigated in this paper. A technoeconomic multi-objective function is introduced to reveal an optimal load shedding scheme considering maximum social welfare. The proposed optimization problem includes maximum GENCOs and loads' profits as well as maximum loadability limit under normal and contingency conditions. Particle swarm optimization (PSO) as a heuristic optimization technique, is utilized to find an optimal load shedding scheme. In a market-driven structure, generators offer their bidding blocks while the dispatchable loads will bid their price-responsive demands. An independent system operator (ISO) derives a market clearing price (MCP) while rescheduling the amount of generating power in both pre-contingency and post-contingency conditions. The proposed methodology is developed on a 3-bus system and then is applied to a modified IEEE 30-bus test system. The obtained results show the effectiveness of the proposed methodology in implementing the optimal load shedding satisfying social welfare by maintaining voltage stability margin (VSM) through technoeconomic analyses.

Technical assistance for law-enforcement communications: Case study report

NASA Technical Reports Server (NTRS)

Reilly, N. B.; Mustain, J. A.

1979-01-01

Methods developed to improve police communications systems are described. Use of queueing analysis shows several ways of improving time of response to inquiries made from the field for license plate checks and for information on current wants and warrants, through a state multiple switcher network. Design criteria for more efficient centralized switching equipment are developed. A message load problem experienced in a dispatch center is analyzed, showing that communications could be improved by adding communications channels, not by adding people.

The useful potential of using existing data to uniquely identify predictable wind events and regimes, part 1

NASA Technical Reports Server (NTRS)

Trettel, D. W.; Aquino, J. T.; Piazza, T. R.; Taylor, L. E.; Trask, D. C.

1982-01-01

Correlations between standard meteorological data and wind power generation potential were developed. Combined with appropriate wind forecasts, these correlations can be useful to load dispatchers to supplement conventional energy sources. Hourly wind data were analyzed for four sites, each exhibiting a unique physiography. These sites are Amarillo, Texas; Ludington, Michigan; Montauk Point, New York; and San Gorgonio, California. Synoptic weather maps and tables are presented to illustrate various wind 'regimes' at these sites.

17. VIEW OF ANCHOR BRIDGE NUMBER 310 LOOKING EAST ALONG ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. VIEW OF ANCHOR BRIDGE NUMBER 310 LOOKING EAST ALONG THE MAIN LINE TRACK LOCATED TO THE NORTH OF THE COS COB POWER PLANT. ANCHOR BRIDGES LOCATED AT TWO MILE INTERVALS WITHSTAND CATENARY TENSION AND PROVIDE A PLATFORM FOR MOUNTING OIL FILLED CIRCUIT BREAKERS, LIGHTNING ARRESTORS AND OTHER ELECTRICAL EQUIPMENT. THE ROOF OF THE LOAD DISPATCHER'S TOWER CAN BE SEEN DIRECTLY BEHIND THE RIGHT SIDE OF THE BRIDGE. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

Optimal Control of Distributed Energy Resources using Model Predictive Control

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

Mayhorn, Ebony T.; Kalsi, Karanjit; Elizondo, Marcelo A.

2012-07-22

In an isolated power system (rural microgrid), Distributed Energy Resources (DERs) such as renewable energy resources (wind, solar), energy storage and demand response can be used to complement fossil fueled generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation. The problem is formulated as a multi-objective optimization problem with the goals of minimizing fuel costs and changes in power output of diesel generators, minimizingmore » costs associated with low battery life of energy storage and maintaining system frequency at the nominal operating value. Two control modes are considered for controlling the energy storage to compensate either net load variability or wind variability. Model predictive control (MPC) is used to solve the aforementioned problem and the performance is compared to an open-loop look-ahead dispatch problem. Simulation studies using high and low wind profiles, as well as, different MPC prediction horizons demonstrate the efficacy of the closed-loop MPC in compensating for uncertainties in wind and demand.« less

Dispatching power system for preventive and corrective voltage collapse problem in a deregulated power system

NASA Astrophysics Data System (ADS)

Alemadi, Nasser Ahmed

Deregulation has brought opportunities for increasing efficiency of production and delivery and reduced costs to customers. Deregulation has also bought great challenges to provide the reliability and security customers have come to expect and demand from the electrical delivery system. One of the challenges in the deregulated power system is voltage instability. Voltage instability has become the principal constraint on power system operation for many utilities. Voltage instability is a unique problem because it can produce an uncontrollable, cascading instability that results in blackout for a large region or an entire country. In this work we define a system of advanced analytical methods and tools for secure and efficient operation of the power system in the deregulated environment. The work consists of two modules; (a) contingency selection module and (b) a Security Constrained Optimization module. The contingency selection module to be used for voltage instability is the Voltage Stability Security Assessment and Diagnosis (VSSAD). VSSAD shows that each voltage control area and its reactive reserve basin describe a subsystem or agent that has a unique voltage instability problem. VSSAD identifies each such agent. VS SAD is to assess proximity to voltage instability for each agent and rank voltage instability agents for each contingency simulated. Contingency selection and ranking for each agent is also performed. Diagnosis of where, why, when, and what can be done to cure voltage instability for each equipment outage and transaction change combination that has no load flow solution is also performed. A security constrained optimization module developed solves a minimum control solvability problem. A minimum control solvability problem obtains the reactive reserves through action of voltage control devices that VSSAD determines are needed in each agent to obtain solution of the load flow. VSSAD makes a physically impossible recommendation of adding reactive generation capability to specific generators to allow a load flow solution to be obtained. The minimum control solvability problem can also obtain solution of the load flow without curtailing transactions that shed load and generation as recommended by VSSAD. A minimum control solvability problem will be implemented as a corrective control, that will achieve the above objectives by using minimum control changes. The control includes; (1) voltage setpoint on generator bus voltage terminals; (2) under load tap changer tap positions and switchable shunt capacitors; and (3) active generation at generator buses. The minimum control solvability problem uses the VSSAD recommendation to obtain the feasible stable starting point but completely eliminates the impossible or onerous recommendation made by VSSAD. This thesis reviews the capabilities of Voltage Stability Security Assessment and Diagnosis and how it can be used to implement a contingency selection module for the Open Access System Dispatch (OASYDIS). The OASYDIS will also use the corrective control computed by Security Constrained Dispatch. The corrective control would be computed off line and stored for each contingency that produces voltage instability. The control is triggered and implemented to correct the voltage instability in the agent experiencing voltage instability only after the equipment outage or operating changes predicted to produce voltage instability have occurred. The advantages and the requirements to implement the corrective control are also discussed.

Status Report on Modelling and Simulation Capabilities for Nuclear-Renewable Hybrid Energy Systems

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

Rabiti, C.; Epiney, A.; Talbot, P.

This report summarizes the current status of the modeling and simulation capabilities developed for the economic assessment of Nuclear-Renewable Hybrid Energy Systems (N-R HES). The increasing penetration of variable renewables is altering the profile of the net demand, with which the other generators on the grid have to cope. N-R HES analyses are being conducted to determine the potential feasibility of mitigating the resultant volatility in the net electricity demand by adding industrial processes that utilize either thermal or electrical energy as stabilizing loads. This coordination of energy generators and users is proposed to mitigate the increase in electricity costmore » and cost volatility through the production of a saleable commodity. Overall, the financial performance of a system that is comprised of peaking units (i.e. gas turbine), baseload supply (i.e. nuclear power plant), and an industrial process (e.g. hydrogen plant) should be optimized under the constraint of satisfying an electricity demand profile with a certain level of variable renewable (wind) penetration. The optimization should entail both the sizing of the components/subsystems that comprise the system and the optimal dispatch strategy (output at any given moment in time from the different subsystems). Some of the capabilities here described have been reported separately in [1, 2, 3]. The purpose of this report is to provide an update on the improvement and extension of those capabilities and to illustrate their integrated application in the economic assessment of N-R HES.« less

Visualization of the Eastern Renewable Generation Integration Study: Preprint

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

Gruchalla, Kenny; Novacheck, Joshua; Bloom, Aaron

The Eastern Renewable Generation Integration Study (ERGIS), explores the operational impacts of the wide spread adoption of wind and solar photovoltaics (PV) resources in the U.S. Eastern Interconnection and Quebec Interconnection (collectively, EI). In order to understand some of the economic and reliability challenges of managing hundreds of gigawatts of wind and PV generation, we developed state of the art tools, data, and models for simulating power system operations using hourly unit commitment and 5-minute economic dispatch over an entire year. Using NREL's high-performance computing capabilities and new methodologies to model operations, we found that the EI, as simulated withmore » evolutionary change in 2026, could balance the variability and uncertainty of wind and PV at a 5-minute level under a variety of conditions. A large-scale display and a combination of multiple coordinated views and small multiples were used to visually analyze the four large highly multivariate scenarios with high spatial and temporal resolutions. state of the art tools, data, and models for simulating power system operations using hourly unit commitment and 5-minute economic dispatch over an entire year. Using NRELs high-performance computing capabilities and new methodologies to model operations, we found that the EI, as simulated with evolutionary change in 2026, could balance the variability and uncertainty of wind and PV at a 5-minute level under a variety of conditions. A large-scale display and a combination of multiple coordinated views and small multiples were used to visually analyze the four large highly multivariate scenarios with high spatial and temporal resolutions.« less

Dispatcher assistance and automated external defibrillator performance among elders.

PubMed

Ecker, R; Rea, T D; Meischke, H; Schaeffer, S M; Kudenchuk, P; Eisenberg, M S

2001-10-01

Automated external defibrillators (AEDs) provide an opportunity to improve survival in out-of-hospital, ventricular fibrillation (VF) cardiac arrest by enabling laypersons not trained in rhythm recognition to deliver lifesaving therapy. The potential role of emergency dispatchers in the layperson use of AEDs is uncertain. This study was performed to examine whether dispatcher telephone assistance affected AED skill performance during a simulated VF cardiac arrest among a cohort of older adults. The hypothesis was that dispatcher assistance would increase the proportion who were able to correctly deliver a shock, but might require additional time. One hundred fifty community-dwelling persons aged 58-84 years were recruited from eight senior centers in King County, Washington. All participants had received AED training approximately six months previously. For this study, the participants were randomized to AED operation with or without dispatcher assistance during a simulated VF cardiac arrest. The proportions who successfully delivered a shock and the time intervals from collapse to shock were compared between the two groups. The participants who received dispatcher assistance were more likely to correctly deliver a shock with the AED during the simulated VF cardiac arrest (91% vs 68%, p = 0.001). Among those who were able to deliver a shock, the participants who received dispatcher assistance required a longer time interval from collapse to shock [median (25th, 75th percentile) = 193 seconds (165, 225) for dispatcher assistance, and 148 seconds (138, 166) for no dispatcher assistance, p = 0.001]. Among older laypersons previously trained in AED operation, dispatcher assistance may increase the proportion who can successfully deliver a shock during a VF cardiac arrest.

8760-Based Method for Representing Variable Generation Capacity Value in Capacity Expansion Models: Preprint

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

Frew, Bethany A; Cole, Wesley J; Sun, Yinong

Capacity expansion models (CEMs) are widely used to evaluate the least-cost portfolio of electricity generators, transmission, and storage needed to reliably serve demand over the evolution of many years or decades. Various CEM formulations are used to evaluate systems ranging in scale from states or utility service territories to national or multi-national systems. CEMs can be computationally complex, and to achieve acceptable solve times, key parameters are often estimated using simplified methods. In this paper, we focus on two of these key parameters associated with the integration of variable generation (VG) resources: capacity value and curtailment. We first discuss commonmore » modeling simplifications used in CEMs to estimate capacity value and curtailment, many of which are based on a representative subset of hours that can miss important tail events or which require assumptions about the load and resource distributions that may not match actual distributions. We then present an alternate approach that captures key elements of chronological operation over all hours of the year without the computationally intensive economic dispatch optimization typically employed within more detailed operational models. The updated methodology characterizes the (1) contribution of VG to system capacity during high load and net load hours, (2) the curtailment level of VG, and (3) the potential reductions in curtailments enabled through deployment of storage and more flexible operation of select thermal generators. We apply this alternate methodology to an existing CEM, the Regional Energy Deployment System (ReEDS). Results demonstrate that this alternate approach provides more accurate estimates of capacity value and curtailments by explicitly capturing system interactions across all hours of the year. This approach could be applied more broadly to CEMs at many different scales where hourly resource and load data is available, greatly improving the representation of challenges associate with integration of variable generation resources.« less

Real-time pricing strategy of micro-grid energy centre considering price-based demand response

NASA Astrophysics Data System (ADS)

Xu, Zhiheng; Zhang, Yongjun; Wang, Gan

2017-07-01

With the development of energy conversion technology such as power to gas (P2G), fuel cell and so on, the coupling between energy sources becomes more and more closely. Centralized dispatch among electricity, natural gas and heat will become a trend. With the goal of maximizing the system revenue, this paper establishes the model of micro-grid energy centre based on energy hub. According to the proposed model, the real-time pricing strategy taking into account price-based demand response of load is developed. And the influence of real-time pricing strategy on the peak load shifting is discussed. In addition, the impact of wind power predicted inaccuracy on real-time pricing strategy is analysed.

Effects of Dispatcher-assisted Cardiopulmonary Resuscitation on Survival Outcomes in Infants, Children, and Adolescents with Out-of-hospital Cardiac Arrests.

PubMed

Ro, Young Sun; Shin, Sang Do; Song, Kyoung Jun; Hong, Ki Jeong; Ahn, Ki Ok; Kim, Do Kyun; Kwak, Young Ho

2016-11-01

We studied the effect of a dispatcher-assisted cardiopulmonary resuscitation (CPR) program on paediatric out-of-hospital cardiac arrest (OHCA) outcomes by age groups. All emergency medical services (EMS)-treated paediatric OHCAs in Korea were enrolled between 2012 and 2014, excluding cases witnessed by EMS providers and those with unknown outcomes. The cases were divided into three groups: bystander CPR with dispatcher assistance, bystander CPR without dispatcher assistance, and no-bystander CPR. The endpoint was survival until discharge from hospital. Multivariable logistic regression analysis was performed. The final model with an interaction term was evaluated to compare the effects across age groups. A total of 1529 patients (32.8% bystander CPR with dispatcher assistance, 17.3% without dispatcher assistance, and 54.6% no-bystander CPR) were included. Both bystander CPR groups were more likely to have higher rate of survival to discharge (8.8% and 12.1%) compared to no-bystander CPR (3.9%). The adjusted OR (95% CI) for survival to discharge were 1.77 (1.04-3.00) in bystander CPR with dispatcher assistance and 2.86 (1.61-5.08) in without dispatcher assistance compared with no-bystander CPR. By age groups, the adjusted OR (95% CI) in bystander CPR with and without dispatcher assistance were 2.18 (1.07-4.42) and 2.27 (1.01-5.14) for the group aged 9-18 years; 2.32 (0.64-8.44) and 6.21 (1.83-21.01) for the group aged 1-8 years; 1.06 (0.41-2.77) and 2.00 (0.64-6.18) for the group aged 0-12 months, respectively. Bystander CPR, regardless of dispatcher assistance, was associated with improved survival outcomes after OHCA in the paediatric population. However, the associations between dispatcher-assisted bystander CPR and survival outcomes varied by age. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Comparison of Medical Priority Dispatch (MPD) and Criteria Based Dispatch (CBD) relating to cardiac arrest calls.

PubMed

Hardeland, Camilla; Olasveengen, Theresa M; Lawrence, Rob; Garrison, Danny; Lorem, Tonje; Farstad, Gunnar; Wik, Lars

2014-05-01

Prompt emergency medical service (EMS) system activation with rapid delivery of pre-hospital treatment is essential for patients suffering out-of-hospital cardiac arrest (OHCA). The two most commonly used dispatch tools are Medical Priority Dispatch (MPD) and Criteria Based Dispatch (CBD). We compared cardiac arrest call processing using these two dispatch tools in two different dispatch centres. Observational study of adult EMS confirmed (non-EMS witnessed) OHCA calls during one year in Richmond, USA (MPD) and Oslo, Norway (CBD). Patients receiving CPR prior to call, interrupted calls or calls where the caller did not have access to the patients were excluded from analysis. Dispatch logs, ambulance records and digitalized dispatcher and caller voice recordings were compared. The MPDS-site processed 182 cardiac arrest calls and the CBD-site 232, of which 100 and 140 calls met the inclusion criteria, respectively. The recognition of cardiac arrest was not different in the MPD and CBD systems; 82% vs. 77% (p=0.42), and pre-EMS arrival CPR instructions were offered to 81% vs. 74% (p=0.22) of callers, respectively. Time to ambulance dispatch was median (95% confidence interval) 15 (13, 17) vs. 33 (29, 36) seconds (p<0.001) and time to chest compression delivery; 4.3 (3.7, 4.9) vs. 3.7 (3.0, 4.1)min for the MPD and CBD systems, respectively (p=0.05). Pre-arrival CPR instructions were offered faster and more frequently in the CBD system, but in both systems chest compressions were delayed 3-4min. Earlier recognition of cardiac arrest and improved CPR instructions may facilitate earlier lay rescuer CPR. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Emergency medical dispatch : national standard curriculum ready

DOT National Transportation Integrated Search

1996-05-01

This Traffic Tech describes the recently updated "Emergency Medical Dispatch: National Standard Curriculum," which was developed in 1972. Emergency service providers use these uniform standards to develop or select an emergency medical dispatch progr...

Ambulance dispatches to schools during a 5-year period in Fukui Prefecture.

PubMed

Takinami, Yoshikazu; Maeda, Shinji

2017-01-01

To determine the characteristics and trends of medical emergencies during school activities by analyzing information provided by fire departments. During a 5-year period from January 2009 to December 2013, all nine fire departments in Fukui Prefecture handled 850 emergencies at schools. We investigated the 850 cases with the age range of 0-63 years. It was found that 21.5% of ambulance dispatches to schools were on weekends and there were more dispatches for non-faculty members of all age groups on weekends than on weekdays. The percentage of weekend dispatches was particularly high for students aged ≥19 years. Emergency calls for junior high school students and younger students accounted for the majority of weekday calls. There were a total of 524 ambulance dispatches for the three categories "sprains, contusions, dislocations, and fractures" ( n = 245), "seizures, epilepsy, and syncope" ( n = 171), and "cuts, bruises, lacerations, trauma, amputations, and burns" ( n = 108), with dispatches for these three categories accounting for 61.6% of all dispatches. Almost all dispatches for "heat stroke and dehydration" were during school hours and were concentrated between the months of July and September. Heat stroke was most common among high school students and most often occurred during the summer/fall season and on weekends. Heat stroke was the fourth most frequent condition that required an ambulance dispatch after the above three conditions. Heat stroke is predictable, indicating that it is necessary to prevent heat stroke during high school club activities.

Real -time dispatching modelling for trucks with different capacities in open pit mines / Modelowanie w czasie rzeczywistym przewozów ciężarówek o różnej ładowności w kopalni odkrywkowej

NASA Astrophysics Data System (ADS)

Ahangaran, Daryoush Kaveh; Yasrebi, Amir Bijan; Wetherelt, Andy; Foster, Patrick

2012-10-01

Application of fully automated systems for truck dispatching plays a major role in decreasing the transportation costs which often represent the majority of costs spent on open pit mining. Consequently, the application of a truck dispatching system has become fundamentally important in most of the world's open pit mines. Recent experiences indicate that by decreasing a truck's travelling time and the associated waiting time of its associated shovel then due to the application of a truck dispatching system the rate of production will be considerably improved. Computer-based truck dispatching systems using algorithms, advanced and accurate software are examples of these innovations. Developing an algorithm of a computer- based program appropriated to a specific mine's conditions is considered as one of the most important activities in connection with computer-based dispatching in open pit mines. In this paper the changing trend of programming and dispatching control algorithms and automation conditions will be discussed. Furthermore, since the transportation fleet of most mines use trucks with different capacities, innovative methods, operational optimisation techniques and the best possible methods for developing the required algorithm for real-time dispatching are selected by conducting research on mathematical-based planning methods. Finally, a real-time dispatching model compatible with the requirement of trucks with different capacities is developed by using two techniques of flow networks and integer programming.

Did Geomagnetic Activity Challenge Electric Power Reliability During Solar Cycle 23? Evidence from the PJM Regional Transmission Organization in North America

NASA Technical Reports Server (NTRS)

Forbes, Kevin F.; Cyr, Chris St

2012-01-01

During solar cycle 22, a very intense geomagnetic storm on 13 March 1989 contributed to the collapse of the Hydro-Quebec power system in Canada. This event clearly demonstrated that geomagnetic storms have the potential to lead to blackouts. This paper addresses whether geomagnetic activity challenged power system reliability during solar cycle 23. Operations by PJM Interconnection, LLC (hereafter PJM), a regional transmission organization in North America, are examined over the period 1 April 2002 through 30 April 2004. During this time PJM coordinated the movement of wholesale electricity in all or parts of Delaware, Maryland, New Jersey, Ohio, Pennsylvania, Virginia, West Virginia, and the District of Columbia in the United States. We examine the relationship between a proxy of geomagnetically induced currents (GICs) and a metric of challenged reliability. In this study, GICs are proxied using magnetometer data from a geomagnetic observatory located just outside the PJM control area. The metric of challenged reliability is the incidence of out-of-economic-merit order dispatching due to adverse reactive power conditions. The statistical methods employed make it possible to disentangle the effects of GICs on power system operations from purely terrestrial factors. The results of the analysis indicate that geomagnetic activity can significantly increase the likelihood that the system operator will dispatch generating units based on system stability considerations rather than economic merit.

Executor Framework for DIRAC

NASA Astrophysics Data System (ADS)

Casajus Ramo, A.; Graciani Diaz, R.

2012-12-01

DIRAC framework for distributed computing has been designed as a group of collaborating components, agents and servers, with persistent database back-end. Components communicate with each other using DISET, an in-house protocol that provides Remote Procedure Call (RPC) and file transfer capabilities. This approach has provided DIRAC with a modular and stable design by enforcing stable interfaces across releases. But it made complicated to scale further with commodity hardware. To further scale DIRAC, components needed to send more queries between them. Using RPC to do so requires a lot of processing power just to handle the secure handshake required to establish the connection. DISET now provides a way to keep stable connections and send and receive queries between components. Only one handshake is required to send and receive any number of queries. Using this new communication mechanism DIRAC now provides a new type of component called Executor. Executors process any task (such as resolving the input data of a job) sent to them by a task dispatcher. This task dispatcher takes care of persisting the state of the tasks to the storage backend and distributing them among all the Executors based on the requirements of each task. In case of a high load, several Executors can be started to process the extra load and stop them once the tasks have been processed. This new approach of handling tasks in DIRAC makes Executors easy to replace and replicate, thus enabling DIRAC to further scale beyond the current approach based on polling agents.

The Future Impact of Wind on BPA Power System Load Following and Regulation Requirements

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

Makarov, Yuri V.; Lu, Shuai; McManus, Bart

Wind power is growing in a very fast pace as an alternative generating resource. As the ratio of wind power over total system capacity increases, the impact of wind on various system aspects becomes significant. This paper presents a methodology to study the future impact of wind on BPA power system load following and regulation requirements. Existing methodologies for similar analysis include dispatch model simulation and standard deviation evaluation on load and wind data. The methodology proposed in this paper uses historical data and stochastic processes to simulate the load balancing processes in the BPA power system. It mimics themore » actual power system operations therefore the results are close to reality yet the study based on this methodology is convenient to perform. The capacity, ramp rate and ramp duration characteristics are extracted from the simulation results. System load following and regulation capacity requirements are calculated accordingly. The ramp rate and ramp duration data obtained from the analysis can be used to evaluate generator response or maneuverability requirement and regulating units’ energy requirement, respectively.« less

Technoeconomic Modeling of Battery Energy Storage in SAM

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

DiOrio, Nicholas; Dobos, Aron; Janzou, Steven

Detailed comprehensive lead-acid and lithium-ion battery models have been integrated with photovoltaic models in an effort to allow System Advisor Model (SAM) to offer the ability to predict the performance and economic benefit of behind the meter storage. In a system with storage, excess PV energy can be saved until later in the day when PV production has fallen, or until times of peak demand when it is more valuable. Complex dispatch strategies can be developed to leverage storage to reduce energy consumption or power demand based on the utility rate structure. This document describes the details of the batterymore » performance and economic models in SAM.« less

Decreasing the dispatch time of medical reports sent from hospital to primary care with Lean Six Sigma.

PubMed

Basta, Yara L; Zwetsloot, Inez M; Klinkenbijl, Jean H G; Rohof, Thomas; Monster, Mathijs M C; Fockens, Paul; Tytgat, Kristien M A J

2016-10-01

Timely communication is important to ensure high-quality health care. To facilitate this, the Gastro Intestinal Oncology Center Amsterdam (GIOCA) stipulated to dispatch medical reports on the day of the patient's visit. However, with the increasing number of patients, administrative processes at GIOCA were under pressure, and this standard was not met for the majority of patients. The aim and objective of this study was to dispatch 90% of medical reports on the day of the patient's visit by improving the logistic process. To assess the main causes for a prolonged dispatch time and to design improvements actions, the roadmap offered by Lean Six Sigma (LSS) was used, consisting of five phases: Define, Measure, Analyze, Improve and Control (DMAIC roadmap). Initially, 12.3% of the reports were dispatched on the day of the patient's visit. Three causes for a prolonged dispatch time were identified: (1) determining which doctors involved with treatment would compose the report; (2) the reports composed by a senior resident had to be reviewed by a medical specialist; and (3) a medical specialist had to authorize the administration to dispatch the reports. To circumvent these causes, a digital form was implemented in the electronic medical record that could be completed during the multidisciplinary team meeting. After implementation, 90.6% of the reports were dispatched on the day of the visit. The dispatch time of reports sent from hospital to primary care can be significantly reduced using Lean Six Sigma, improving the communication between hospital and primary care. © 2016 John Wiley & Sons, Ltd.

Modeling work of the dispatching service of high-rise building as queuing system

NASA Astrophysics Data System (ADS)

Dement'eva, Marina; Dement'eva, Anastasiya

2018-03-01

The article presents the results of calculating the performance indicators of the dispatcher service of a high-rise building as a queuing system with an unlimited queue. The calculation was carried out for three models: with a single control room and brigade of service, with a single control room and a specialized service, with several dispatch centers and specialized services. The aim of the work was to investigate the influence of the structural scheme of the organization of the dispatcher service of a high-rise building on the amount of operating costs and the time of processing and fulfilling applications. The problems of high-rise construction and their impact on the complication of exploitation are analyzed. The composition of exploitation activities of high-rise buildings is analyzed. The relevance of the study is justified by the need to review the role of dispatch services in the structure of management of the quality of buildings. Dispatching service from the lower level of management of individual engineering systems becomes the main link in the centralized automated management of the exploitation of high-rise buildings. With the transition to market relations, the criterion of profitability at the organization of the dispatching service becomes one of the main parameters of the effectiveness of its work. A mathematical model for assessing the efficiency of the dispatching service on a set of quality of service indicators is proposed. The structure of operating costs is presented. The algorithm of decision-making is given when choosing the optimal structural scheme of the dispatching service of a high-rise building.

Training requirements for railroad dispatchers : objectives, syllabi and test designs

DOT National Transportation Integrated Search

1998-11-01

This report presents the results of a study to develop railroad dispatcher training objectives, syllabi for three types of training programs and test designs for the three programs. Information about current railroad dispatching methods and training ...

Optimizing Staffing levels and Schedules for Railroad Dispatching Centers

DOT National Transportation Integrated Search

2004-09-01

This report presents the results of a study to explore approaches to establishing staffing levels and schedules for railroad dispatchers. The : work was conducted as follow-up to a prior study that found fatigue among dispatchers, particularly those ...

Dispatch-assisted CPR: where are the hold-ups during calls to emergency dispatchers? A preliminary analysis of caller-dispatcher interactions during out-of-hospital cardiac arrest using a novel call transcription technique.

PubMed

Clegg, Gareth R; Lyon, Richard M; James, Scott; Branigan, Holly P; Bard, Ellen G; Egan, Gerry J

2014-01-01

Survival from out-of-hospital cardiac arrest (OHCA) is dependent on the chain of survival. Early recognition of cardiac arrest and provision of bystander cardiopulmonary resuscitation (CPR) are key determinants of OHCA survival. Emergency medical dispatchers play a key role in cardiac arrest recognition and giving telephone CPR advice. The interaction between caller and dispatcher can influence the time to bystander CPR and quality of resuscitation. We sought to pilot the use of emergency call transcription to audit and evaluate the holdups in performing dispatch-assisted CPR. A retrospective case selection of 50 consecutive suspected OHCA was performed. Audio recordings of calls were downloaded from the emergency medical dispatch centre computer database. All calls were transcribed using proprietary software and voice dialogue was compared with the corresponding stage on the Medical Priority Dispatch System (MPDS). Time to progress through each stage and number of caller-dispatcher interactions were calculated. Of the 50 downloaded calls, 47 were confirmed cases of OHCA. Call transcription was successfully completed for all OHCA calls. Bystander CPR was performed in 39 (83%) of these. In the remaining cases, the caller decided the patient was beyond help (n = 7) or the caller said that they were physically unable to perform CPR (n = 1). MPDS stages varied substantially in time to completion. Stage 9 (determining if the patient is breathing through airway instructions) took the longest time to complete (median = 59 s, IQR 22-82 s). Stage 11 (giving CPR instructions) also took a relatively longer time to complete compared to the other stages (median = 46 s, IQR 37-75 s). Stage 5 (establishing the patient's age) took the shortest time to complete (median = 5.5s, IQR 3-9s). Transcription of OHCA emergency calls and caller-dispatcher interaction compared to MPDS stage is feasible. Confirming whether a patient is breathing and completing CPR instructions required the longest time and most interactions between caller and dispatcher. Use of call transcription has the potential to identify key factors in caller-dispatcher interaction that could improve time to CPR and further research is warranted in this area. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Understanding how train dispatchers manage and control trains : results of a cognitive task analysis

DOT National Transportation Integrated Search

2001-05-01

This report documents the results of a Cognitive Task Analysis that examined how experienced railroad dispatchers manage and : schedule trains in todays environment. The objective was to understand the cognitive demands placed on railroad dispatch...

Understanding how train dispatchers manage and control trains : results of a cognitive task analysis

DOT National Transportation Integrated Search

2001-05-01

This report documents the results ofaCognitive Task Analysis that examined how experienced railroad dispatchers manage and : schedule trains in today's environment. The objective was to understand the cognitive demands placed on railroad dispatchers ...

Understanding how train dispatchers manage and control trains : results of a cognitive task analysis.

DOT National Transportation Integrated Search

2001-05-01

This report documents the results of a Cognitive Task Analysis that examined how experienced railroad dispatchers manage and schedule trains in todays environment. The objective was to understand the cognitive demands placed on railroad dispatcher...

The U.S. - Japan Security Alliance: Will it Survive in the New World Order?

DTIC Science & Technology

1991-04-01

34 Washinqton Post, October 17, 1990, p. A-18. 97. Ibid. 98. Henry Cutter, Diet Takes Up Troop Dispatch Plan, ’ Japan Times, October 22-28, 1990. 99. Charles ...11. Auer, James E. "Japanis Defense Policy." Current Histpy. Vol. 87, April 1988, pp. 145-148. Babbage , Ross. "Change in the North Pacific...Smith, Charles . "Stretching Things-." Fara&a Etern.Eonomic Review. November 1, 1990, p. 16. Smith, Charles . "Vacuum Gleaner." Far Eastern Economic

Research on Novel Algorithms for Smart Grid Reliability Assessment and Economic Dispatch

NASA Astrophysics Data System (ADS)

Luo, Wenjin

In this dissertation, several studies of electric power system reliability and economy assessment methods are presented. To be more precise, several algorithms in evaluating power system reliability and economy are studied. Furthermore, two novel algorithms are applied to this field and their simulation results are compared with conventional results. As the electrical power system develops towards extra high voltage, remote distance, large capacity and regional networking, the application of a number of new technique equipments and the electric market system have be gradually established, and the results caused by power cut has become more and more serious. The electrical power system needs the highest possible reliability due to its complication and security. In this dissertation the Boolean logic Driven Markov Process (BDMP) method is studied and applied to evaluate power system reliability. This approach has several benefits. It allows complex dynamic models to be defined, while maintaining its easy readability as conventional methods. This method has been applied to evaluate IEEE reliability test system. The simulation results obtained are close to IEEE experimental data which means that it could be used for future study of the system reliability. Besides reliability, modern power system is expected to be more economic. This dissertation presents a novel evolutionary algorithm named as quantum evolutionary membrane algorithm (QEPS), which combines the concept and theory of quantum-inspired evolutionary algorithm and membrane computation, to solve the economic dispatch problem in renewable power system with on land and offshore wind farms. The case derived from real data is used for simulation tests. Another conventional evolutionary algorithm is also used to solve the same problem for comparison. The experimental results show that the proposed method is quick and accurate to obtain the optimal solution which is the minimum cost for electricity supplied by wind farm system.

Managing Sustainable Demand-side Infrastructure for Power System Ancillary Services

NASA Astrophysics Data System (ADS)

Parkinson, Simon Christopher

Widespread access to renewable electricity is seen as a viable method to mitigate carbon emissions, although problematic are the issues associated with the integration of the generation systems within current power system configurations. Wind power plants are the primary large-scale renewable generation technology applied globally, but display considerable short-term supply variability that is difficult to predict. Power systems are currently not designed to operate under these conditions, and results in the need to increase operating reserve in order to guarantee stability. Often, operating conventional generation as reserve is both technically and economically inefficient, which can overshadow positive benefits associated with renewable energy exploitation. The purpose of this thesis is to introduce and assess an alternative method of enhancing power system operations through the control of electric loads. In particular, this thesis focuses on managing highly-distributed sustainable demand-side infrastructure, in the form of heat pumps, electric vehicles, and electrolyzers, as dispatchable short-term energy balancing resources. The main contribution of the thesis is an optimal control strategy capable of simultaneously balancing grid- and demand-side objectives. The viability of the load control strategy is assessed through model-based simulations that explicitly track end-use functionality of responsive devices within a power systems analysis typically implemented to observe the effects of integrated wind energy systems. Results indicate that there is great potential for the proposed method to displace the need for increased reserve capacity in systems considering a high penetration of wind energy, thereby allowing conventional generation to operate more efficiently and avoid the need for possible capacity expansions.

14 CFR 121.533 - Responsibility for operational control: Domestic operations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations... aircraft dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight in compliance with this chapter and operations specifications. (c) The aircraft dispatcher is...

14 CFR 121.533 - Responsibility for operational control: Domestic operations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations... aircraft dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight in compliance with this chapter and operations specifications. (c) The aircraft dispatcher is...

14 CFR 121.533 - Responsibility for operational control: Domestic operations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations... aircraft dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight in compliance with this chapter and operations specifications. (c) The aircraft dispatcher is...

14 CFR 121.422 - Aircraft dispatchers: Initial and transition ground training.

Code of Federal Regulations, 2011 CFR

2011-01-01

... computations; (iv) Basic airplane performance dispatch requirements and procedures; (v) Flight planning including track selection, flight time analysis, and fuel requirements; and (vi) Emergency procedures. (3... procedures, and other subjects having a bearing on dispatcher duties and responsibilities; (ii) Flight...

14 CFR 121.533 - Responsibility for operational control: Domestic operations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations... aircraft dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight in compliance with this chapter and operations specifications. (c) The aircraft dispatcher is...

14 CFR 121.422 - Aircraft dispatchers: Initial and transition ground training.

Code of Federal Regulations, 2012 CFR

2012-01-01

... computations; (iv) Basic airplane performance dispatch requirements and procedures; (v) Flight planning including track selection, flight time analysis, and fuel requirements; and (vi) Emergency procedures. (3... procedures, and other subjects having a bearing on dispatcher duties and responsibilities; (ii) Flight...

14 CFR 121.533 - Responsibility for operational control: Domestic operations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations... aircraft dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight in compliance with this chapter and operations specifications. (c) The aircraft dispatcher is...

14 CFR 121.422 - Aircraft dispatchers: Initial and transition ground training.

Code of Federal Regulations, 2013 CFR

2013-01-01

... computations; (iv) Basic airplane performance dispatch requirements and procedures; (v) Flight planning including track selection, flight time analysis, and fuel requirements; and (vi) Emergency procedures. (3... procedures, and other subjects having a bearing on dispatcher duties and responsibilities; (ii) Flight...

14 CFR 121.422 - Aircraft dispatchers: Initial and transition ground training.

Code of Federal Regulations, 2010 CFR

2010-01-01

... computations; (iv) Basic airplane performance dispatch requirements and procedures; (v) Flight planning including track selection, flight time analysis, and fuel requirements; and (vi) Emergency procedures. (3... procedures, and other subjects having a bearing on dispatcher duties and responsibilities; (ii) Flight...

14 CFR 121.422 - Aircraft dispatchers: Initial and transition ground training.

Code of Federal Regulations, 2014 CFR

2014-01-01

... computations; (iv) Basic airplane performance dispatch requirements and procedures; (v) Flight planning including track selection, flight time analysis, and fuel requirements; and (vi) Emergency procedures. (3... procedures, and other subjects having a bearing on dispatcher duties and responsibilities; (ii) Flight...

Expanding the first link in the chain of survival - Experiences from dispatcher referral of callers to AED locations.

PubMed

Fredman, David; Svensson, Leif; Ban, Yifang; Jonsson, Martin; Hollenberg, Jacob; Nordberg, Per; Ringh, Mattias; Rosenqvist, Mårten; Lundén, Margareta; Claesson, Andreas

2016-10-01

Early use of automated external defibrillators (AED) increases survival in cases of out-of-hospital cardiac arrest (OHCA). Dispatchers play important roles in identifying OHCA, dispatching ambulances and providing callers with telephone-assisted cardiopulmonary resuscitation. Guidelines recommend that AED registries be linked to dispatch centres as tools to refer callers to nearby AED. The aim of this study was to investigate to what extent dispatchers, when provided with a tool to display AED locations and accessibility, referred callers to nearby AED. An application providing real-time visualization of AED locations and accessibility was implemented at four dispatch centres in Sweden. Dispatchers were instructed to refer callers to nearby AED when OHCA was suspected. Such cases were prospectively collected, and geographic information systems were used to identify those located ≤100m from an AED. Audio recordings of emergency calls were assessed to evaluate the AED referral rate. Between February and August 2014, 3009 suspected OHCA calls were received. In 6.6% of those calls (200/3009), an AED was ≤100m from the suspected OHCA. The AED was accessible and the caller was not alone on scene in 24% (47/200) of these cases. In two of those 47 cases (4.3%), the dispatcher referred the caller to the AED. Despite a tool for dispatchers to refer callers to a nearby AED, referral was rare. Only a minority of the suspected OHCA cases occurred ≤100m from an AED. We identified AED accessibility and callers being alone on scene as obstacles for AED referral. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Emergency medical dispatch priority in chest pain patients due to life threatening conditions: A cohort study examining circadian variations and impact of the education.

PubMed

Rawshani, Araz; Rawshani, Nina; Gelang, Carita; Andersson, Jan-Otto; Larsson, Anna; Bång, Angela; Herlitz, Johan; Gellerstedt, Martin

2017-06-01

We examined the accuracy in assessments of emergency dispatchers according to their education and time of the day. We examined this in chest pain patients who were diagnosed with a potentially life-threatening condition (LTC) or died within 30days. Among 2205 persons, 482 died, 1631 experienced an acute coronary syndrome (ACS), 1914 had a LTC. Multivariable logistic regression was used to study how time of the call and the dispatcher's education were associated with the risk of missing to give priority 1 (the highest). Among patients who died, a 7-fold increase in odds of missing to give priority 1 was noted at 1.00pm, as compared with midnight. Compared with assistant nurses, odds ratio for dispatchers with no (medical) training was 0.34 (95% CI 0.14 to 0.77). Among patients with an ACS, odds ratio for calls arriving before lunch was 2.02 (95% CI 1.22 to 3.43), compared with midnight. Compared with assistant nurses, odds ratio for operators with no training was 0.23 (95% CI 0.13 to 0.40). Similar associations were noted for those with any LTC. Dispatcher's education was not associated with the patient's survival. In this group of patients, which experience substantial mortality and morbidity, the risk of not obtaining highest dispatch priority was increased up to 7-fold during lunchtime. Dispatch operators without medical education had the lowest risk, compared with nurses and assistant nurses, of missing to give priority 1, at the expense of lower positive predictive value. What is already known about this subject? Use of the emergency medical service (EMS) increases survival among patients with acute coronary syndromes. It is unknown whether the efficiency - as judged by the ability to identify life-threatening cases among patients with chest pain - varies according to the dispatcher's educational level and the time of day. What does this study add? We provide evidence that the dispatcher's education does not influence survival among patients calling the EMS due to chest discomfort. However, medically educated dispatchers are at greatest risk of missing to identify life-threatening cases, which is explained by more parsimonious use of the highest dispatch priority. We also show that the risk of missing life-threatening cases is at highest around lunch time. How might this impact on clinical practice? Dispatch centers are operated differently all over the world and chest discomfort is one of the most frequent symptoms encountered; we provide evidence that it is safe to operate a dispatch center without medically trained personnel, who actually miss fewer cases of acute coronary syndromes. However, non-medically trained dispatchers consume more pre-hospital resources. Copyright © 2017 Elsevier B.V. All rights reserved.

14 CFR 121.463 - Aircraft dispatcher qualifications.

Code of Federal Regulations, 2010 CFR

2010-01-01

... aircraft dispatcher for a particular airplane group unless that person has, with respect to an airplane of that group, satisfactorily completed the following: (1) Initial dispatcher training, except that a person who has satisfactorily completed such training for another type airplane of the same group need...

14 CFR 121.415 - Crewmember and dispatcher training requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... indoctrination ground training for newly hired crewmembers or dispatchers including 40 programmed hours of... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Crewmember and dispatcher training... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Training Program § 121.415 Crewmember...

Influence of dispatching rules on average production lead time for multi-stage production systems.

PubMed

Hübl, Alexander; Jodlbauer, Herbert; Altendorfer, Klaus

2013-08-01

In this paper the influence of different dispatching rules on the average production lead time is investigated. Two theorems based on covariance between processing time and production lead time are formulated and proved theoretically. Theorem 1 links the average production lead time to the "processing time weighted production lead time" for the multi-stage production systems analytically. The influence of different dispatching rules on average lead time, which is well known from simulation and empirical studies, can be proved theoretically in Theorem 2 for a single stage production system. A simulation study is conducted to gain more insight into the influence of dispatching rules on average production lead time in a multi-stage production system. We find that the "processing time weighted average production lead time" for a multi-stage production system is not invariant of the applied dispatching rule and can be used as a dispatching rule independent indicator for single-stage production systems.

Reducing Wind Curtailment through Transmission Expansion in a Wind Vision Future

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

Jorgensen, Jennie; Mai, Trieu; Brinkman, Greg

The Department of Energy's 2015 Wind Vision study, which analyzed an ambitious scenario where wind power served 35% of U.S. electricity consumption in 2050, showed the potential for wind energy to provide substantial health, environmental, and economic benefits. Using a commercial unit commitment and economic dispatch model, we build on this research by assessing the hourly operational feasibility of a similar high wind future in the Western United States. Our detailed simulations found no hours of unmet load or reserve violations with more than 35% potential wind (and 12% potential solar) available on the system, which highlights the technical possibilitymore » of integrating large amounts of wind energy. However, absent significant changes to the western grid, we find that substantial wind curtailment could be an issue, as it could degrade the potential for wind power to reduce fuel costs and lowering the emission benefits. To assess the value of transmission to mitigate wind curtailment, we model a suite of transmission expansion scenarios. We find that wind curtailment could be reduced by approximately half under a scenario where new transmission is based only on proposed projects. This avoided wind curtailment could lower annual production costs and reduce carbon dioxide emissions substantially. Greater transmission expansion was found to yield further benefits, although the marginal benefits of these new lines were found to decline. Overall, these results suggest that power systems operation can be realized with more than 35% wind penetration, but that transmission expansion is likely to play a vital role.« less

14 CFR 121.404 - Compliance dates: Crew and dispatcher resource management training.

Code of Federal Regulations, 2010 CFR

2010-01-01

... approved crew resource management (CRM) or dispatcher resource management (DRM) initial training, as... resource management training. 121.404 Section 121.404 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... § 121.404 Compliance dates: Crew and dispatcher resource management training. After March 19, 1998, no...

14 CFR 121.687 - Dispatch release: Flag and domestic operations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Dispatch release: Flag and domestic operations. 121.687 Section 121.687 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF...) The dispatch release must contain, or have attached to it, weather reports, available weather...

14 CFR 121.687 - Dispatch release: Flag and domestic operations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Dispatch release: Flag and domestic operations. 121.687 Section 121.687 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF...) The dispatch release must contain, or have attached to it, weather reports, available weather...

14 CFR 121.687 - Dispatch release: Flag and domestic operations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Dispatch release: Flag and domestic operations. 121.687 Section 121.687 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF...) The dispatch release must contain, or have attached to it, weather reports, available weather...

14 CFR 121.687 - Dispatch release: Flag and domestic operations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Dispatch release: Flag and domestic operations. 121.687 Section 121.687 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF...) The dispatch release must contain, or have attached to it, weather reports, available weather...

14 CFR 121.687 - Dispatch release: Flag and domestic operations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Dispatch release: Flag and domestic operations. 121.687 Section 121.687 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF...) The dispatch release must contain, or have attached to it, weather reports, available weather...

Solar Thermoelectricity via Advanced Latent Heat Storage

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

Olsen, Michele L.; Rea, J.; Glatzmaier, Greg C.

2016-05-31

We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a 'thermalmore » valve,' which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.« less

Solar thermoelectricity via advanced latent heat storage

NASA Astrophysics Data System (ADS)

Olsen, M. L.; Rea, J.; Glatzmaier, G. C.; Hardin, C.; Oshman, C.; Vaughn, J.; Roark, T.; Raade, J. W.; Bradshaw, R. W.; Sharp, J.; Avery, A. D.; Bobela, D.; Bonner, R.; Weigand, R.; Campo, D.; Parilla, P. A.; Siegel, N. P.; Toberer, E. S.; Ginley, D. S.

2016-05-01

We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a "thermal valve," which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.

Wind farms production: Control and prediction

NASA Astrophysics Data System (ADS)

El-Fouly, Tarek Hussein Mostafa

Wind energy resources, unlike dispatchable central station generation, produce power dependable on external irregular source and that is the incident wind speed which does not always blow when electricity is needed. This results in the variability, unpredictability, and uncertainty of wind resources. Therefore, the integration of wind facilities to utility electrical grid presents a major challenge to power system operator. Such integration has significant impact on the optimum power flow, transmission congestion, power quality issues, system stability, load dispatch, and economic analysis. Due to the irregular nature of wind power production, accurate prediction represents the major challenge to power system operators. Therefore, in this thesis two novel models are proposed for wind speed and wind power prediction. One proposed model is dedicated to short-term prediction (one-hour ahead) and the other involves medium term prediction (one-day ahead). The accuracy of the proposed models is revealed by comparing their results with the corresponding values of a reference prediction model referred to as the persistent model. Utility grid operation is not only impacted by the uncertainty of the future production of wind farms, but also by the variability of their current production and how the active and reactive power exchange with the grid is controlled. To address this particular task, a control technique for wind turbines, driven by doubly-fed induction generators (DFIGs), is developed to regulate the terminal voltage by equally sharing the generated/absorbed reactive power between the rotor-side and the gridside converters. To highlight the impact of the new developed technique in reducing the power loss in the generator set, an economic analysis is carried out. Moreover, a new aggregated model for wind farms is proposed that accounts for the irregularity of the incident wind distribution throughout the farm layout. Specifically, this model includes the wake effect and the time delay of the incident wind speed of the different turbines on the farm, and to simulate the fluctuation in the generated power more accurately and more closer to real-time operation. Recently, wind farms with considerable output power ratings have been installed. Their integrating into the utility grid will substantially affect the electricity markets. This thesis investigates the possible impact of wind power variability, wind farm control strategy, wind energy penetration level, wind farm location, and wind power prediction accuracy on the total generation costs and close to real time electricity market prices. These issues are addressed by developing a single auction market model for determining the real-time electricity market prices.

49 CFR 1242.57 - Dispatching trains (account XX-51-58).

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 9 2010-10-01 2010-10-01 false Dispatching trains (account XX-51-58). 1242.57 Section 1242.57 Transportation Other Regulations Relating to Transportation (Continued) SURFACE...-Transportation § 1242.57 Dispatching trains (account XX-51-58). Separate common expenses on the basis of train...

14 CFR 65.61 - Aircraft dispatcher certification courses: Content and minimum hours.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aircraft dispatcher certification courses: Content and minimum hours. 65.61 Section 65.61 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... aircraft dispatcher certification course must: (1) Provide instruction in the areas of knowledge and topics...

14 CFR 65.61 - Aircraft dispatcher certification courses: Content and minimum hours.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft dispatcher certification courses: Content and minimum hours. 65.61 Section 65.61 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... aircraft dispatcher certification course must: (1) Provide instruction in the areas of knowledge and topics...

A priority dispatch system for emergency medical services.

PubMed

Slovis, C M; Carruth, T B; Seitz, W J; Thomas, C M; Elsea, W R

1985-11-01

A decision tree priority dispatch system for emergency medical services (EMS) was developed and implemented in Atlanta and Fulton County, Georgia. The dispatch system shortened the average response time from 14.2 minutes to 10.4 minutes for the 30% of patients deemed most urgent (P less than or equal to .05); resulted in a significant increase in the use of advanced life support units for this group (P less than or equal to .02); decreased the number of calls that required a backup ambulance service; and significantly increased conformity to national EMS response time standards for critically ill and injured patients (P less than or equal to .0009). Due to dispatch error, 0.3% of calls were dispatched as least severe but subsequently were found to be most urgent.

DISPATCH: a numerical simulation framework for the exa-scale era - I. Fundamentals

NASA Astrophysics Data System (ADS)

Nordlund, Åke; Ramsey, Jon P.; Popovas, Andrius; Küffmeier, Michael

2018-06-01

We introduce a high-performance simulation framework that permits the semi-independent, task-based solution of sets of partial differential equations, typically manifesting as updates to a collection of `patches' in space-time. A hybrid MPI/OpenMP execution model is adopted, where work tasks are controlled by a rank-local `dispatcher' which selects, from a set of tasks generally much larger than the number of physical cores (or hardware threads), tasks that are ready for updating. The definition of a task can vary, for example, with some solving the equations of ideal magnetohydrodynamics (MHD), others non-ideal MHD, radiative transfer, or particle motion, and yet others applying particle-in-cell (PIC) methods. Tasks do not have to be grid based, while tasks that are, may use either Cartesian or orthogonal curvilinear meshes. Patches may be stationary or moving. Mesh refinement can be static or dynamic. A feature of decisive importance for the overall performance of the framework is that time-steps are determined and applied locally; this allows potentially large reductions in the total number of updates required in cases when the signal speed varies greatly across the computational domain, and therefore a corresponding reduction in computing time. Another feature is a load balancing algorithm that operates `locally' and aims to simultaneously minimize load and communication imbalance. The framework generally relies on already existing solvers, whose performance is augmented when run under the framework, due to more efficient cache usage, vectorization, local time-stepping, plus near-linear and, in principle, unlimited OpenMP and MPI scaling.

Enabling the extended compact genetic algorithm for real-parameter optimization by using adaptive discretization.

PubMed

Chen, Ying-ping; Chen, Chao-Hong

2010-01-01

An adaptive discretization method, called split-on-demand (SoD), enables estimation of distribution algorithms (EDAs) for discrete variables to solve continuous optimization problems. SoD randomly splits a continuous interval if the number of search points within the interval exceeds a threshold, which is decreased at every iteration. After the split operation, the nonempty intervals are assigned integer codes, and the search points are discretized accordingly. As an example of using SoD with EDAs, the integration of SoD and the extended compact genetic algorithm (ECGA) is presented and numerically examined. In this integration, we adopt a local search mechanism as an optional component of our back end optimization engine. As a result, the proposed framework can be considered as a memetic algorithm, and SoD can potentially be applied to other memetic algorithms. The numerical experiments consist of two parts: (1) a set of benchmark functions on which ECGA with SoD and ECGA with two well-known discretization methods: the fixed-height histogram (FHH) and the fixed-width histogram (FWH) are compared; (2) a real-world application, the economic dispatch problem, on which ECGA with SoD is compared to other methods. The experimental results indicate that SoD is a better discretization method to work with ECGA. Moreover, ECGA with SoD works quite well on the economic dispatch problem and delivers solutions better than the best known results obtained by other methods in existence.

Analysis of operating reserve demand curves in power system operations in the presence of variable generation

DOE PAGES

Krad, Ibrahim; Gao, David Wenzhong; Ela, Erik; ...

2017-06-07

The electric power industry landscape is continually evolving. As emerging technologies such as wind and solar generating systems become more cost effective, traditional power system operating strategies will need to be re-evaluated. The presence of wind and solar generation (commonly referred to as variable generation or VG) can increase variability and uncertainty in the net-load profile. One mechanism to mitigate this issue is to schedule and dispatch additional operating reserves. These operating reserves aim to ensure that there is enough capacity online in the system to account for the increased variability and uncertainty occurring at finer temporal resolutions. A newmore » operating reserve strategy, referred to as flexibility reserve, has been introduced in some regions. A similar implementation is explored in this study, and its implications on power system operations are analyzed. Results show that flexibility reserve products can improve economic metrics, particularly in significantly reducing the number of scarcity pricing events, with minimal impacts on reliability metrics and production costs. Furthermore, the production costs increased due to increased VG curtailment - i.e. including the flexible ramping product in the commitment of excess thermal capacity that needed to remain online at the expense of VG output.« less

Analysis of operating reserve demand curves in power system operations in the presence of variable generation

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

Krad, Ibrahim; Gao, David Wenzhong; Ela, Erik

The electric power industry landscape is continually evolving. As emerging technologies such as wind and solar generating systems become more cost effective, traditional power system operating strategies will need to be re-evaluated. The presence of wind and solar generation (commonly referred to as variable generation or VG) can increase variability and uncertainty in the net-load profile. One mechanism to mitigate this issue is to schedule and dispatch additional operating reserves. These operating reserves aim to ensure that there is enough capacity online in the system to account for the increased variability and uncertainty occurring at finer temporal resolutions. A newmore » operating reserve strategy, referred to as flexibility reserve, has been introduced in some regions. A similar implementation is explored in this study, and its implications on power system operations are analyzed. Results show that flexibility reserve products can improve economic metrics, particularly in significantly reducing the number of scarcity pricing events, with minimal impacts on reliability metrics and production costs. Furthermore, the production costs increased due to increased VG curtailment - i.e. including the flexible ramping product in the commitment of excess thermal capacity that needed to remain online at the expense of VG output.« less

Optimization under Uncertainty of a Biomass-integrated Renewable Energy Microgrid with Energy Storage

NASA Astrophysics Data System (ADS)

Zheng, Yingying

The growing energy demands and needs for reducing carbon emissions call more and more attention to the development of renewable energy technologies and management strategies. Microgrids have been developed around the world as a means to address the high penetration level of renewable generation and reduce greenhouse gas emissions while attempting to address supply-demand balancing at a more local level. This dissertation presents a model developed to optimize the design of a biomass-integrated renewable energy microgrid employing combined heat and power with energy storage. A receding horizon optimization with Monte Carlo simulation were used to evaluate optimal microgrid design and dispatch under uncertainties in the renewable energy and utility grid energy supplies, the energy demands, and the economic assumptions so as to generate a probability density function for the cost of energy. Case studies were examined for a conceptual utility grid-connected microgrid application in Davis, California. The results provide the most cost effective design based on the assumed energy load profile, local climate data, utility tariff structure, and technical and financial performance of the various components of the microgrid. Sensitivity and uncertainty analyses are carried out to illuminate the key parameters that influence the energy costs. The model application provides a means to determine major risk factors associated with alternative design integration and operating strategies.

Steam dispatching control system demonstration at Fort Benjamin Harrison. Final technical report

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

Diks, C.L.; Moshage, R.E.; Lin, M.C.

1993-07-01

Currently most Army Central steam heating systems operate by maintaining a constant steam pressure regardless of actual steam demand. This method offers some operational convenience, but is often the cause of significant energy losses. Researchers at the U.S. Army Construction Engineering Research Laboratories (USACERL) have investigated the Steam Dispatching Control System (SDCS), a control system that lowers supply steam pressure-and therefore steam temperature-to slightly above the amount needed to meet the steam demand. The lower Steam temperature and reduction in steam loss (from leaks and faulty traps) result in lower heat losses and higher energy savings. Limiting steam pressure canmore » diminish the amount of excess heat loss in the distribution system while still meeting the demand. The Army's Facilities Engineering Applications Program (FEAP) chose Fort Benjamin Harrison, IN, as the Army demonstration site for SDCS. Researchers found that use of SDCS is technically and economically viable improvement over current operating procedures. Analysis based on demonstration results show that the simple payback for SDCS is less than 1 year. The results of this demonstration are generally applicable to installations with a large central heating plant and a substantial steam distribution system. Findings, indicate that energy savings form SDCS are significant regardless of what type of fuel powers the boiler. The authors note that, during the initial evaluation of a potential SDCS application, attention must be paid to the condensate return to ensure that it will operate properly. Fort Benjamin Harrison, IN, Steam Dispatching Control System(SDCS), Central heating plants, energy conservation.« less

77 FR 64977 - Texas Dispatchable Wind 1, LLC; Supplemental Notice That Initial Market-Based Rate Filing...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-24

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ER13-70-000] Texas Dispatchable Wind 1, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for... Texas Dispatchable Wind 1 LLC's application for market-based rate authority, with an accompanying rate...

Information needs for increasing log transport efficiency

Treesearch

Timothy P. McDonald; Steven E. Taylor; Robert B. Rummer; Jorge Valenzuela

2001-01-01

Three methods of dispatching trucks to loggers were tested using a log transport simulation model: random allocation, fixed assignment of trucks to loggers, and dispatch based on knowledge of the current status of trucks and loggers within the system. This 'informed' dispatch algorithm attempted to minimize the difference in time between when a logger would...

14 CFR 121.601 - Aircraft dispatcher information to pilot in command: Domestic and flag operations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... command: Domestic and flag operations. 121.601 Section 121.601 Aeronautics and Space FEDERAL AVIATION... Flight Release Rules § 121.601 Aircraft dispatcher information to pilot in command: Domestic and flag operations. (a) The aircraft dispatcher shall provide the pilot in command all available current reports or...

14 CFR 121.601 - Aircraft dispatcher information to pilot in command: Domestic and flag operations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... command: Domestic and flag operations. 121.601 Section 121.601 Aeronautics and Space FEDERAL AVIATION... Flight Release Rules § 121.601 Aircraft dispatcher information to pilot in command: Domestic and flag operations. (a) The aircraft dispatcher shall provide the pilot in command all available current reports or...

14 CFR 121.601 - Aircraft dispatcher information to pilot in command: Domestic and flag operations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... command: Domestic and flag operations. 121.601 Section 121.601 Aeronautics and Space FEDERAL AVIATION... Flight Release Rules § 121.601 Aircraft dispatcher information to pilot in command: Domestic and flag operations. (a) The aircraft dispatcher shall provide the pilot in command all available current reports or...

14 CFR 121.601 - Aircraft dispatcher information to pilot in command: Domestic and flag operations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... command: Domestic and flag operations. 121.601 Section 121.601 Aeronautics and Space FEDERAL AVIATION... Flight Release Rules § 121.601 Aircraft dispatcher information to pilot in command: Domestic and flag operations. (a) The aircraft dispatcher shall provide the pilot in command all available current reports or...

14 CFR 121.601 - Aircraft dispatcher information to pilot in command: Domestic and flag operations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... command: Domestic and flag operations. 121.601 Section 121.601 Aeronautics and Space FEDERAL AVIATION... Flight Release Rules § 121.601 Aircraft dispatcher information to pilot in command: Domestic and flag operations. (a) The aircraft dispatcher shall provide the pilot in command all available current reports or...

77 FR 12104 - Agency Information Collection Activities: Requests for Comments; Clearance of Renewed Approval of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-28

... Courses AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice and request for comments... certification and approval of aircraft dispatcher courses. The FAA uses the information to ensure compliance and..., Subpart C, Aircraft Dispatchers and App. A Aircraft Dispatcher Courses. Form Numbers: There are no FAA...

VIEW OF THE DISPATCH OFFICE IN BUILDING 331. ALL SITEWIDE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF THE DISPATCH OFFICE IN BUILDING 331. ALL SITE-WIDE FIRE ALARM SIGNALS, INCLUDING ALL FIRE PHONES, FIRE PULL BOXES, HEAT AND SMOKE DETECTORS, AND SUPPRESSION SYSTEM FLOW ALARMS, ARE TRANSMITTED TO THE BUILDING 331 DISPATCHER'S OFFICE. (3/77) - Rocky Flats Plant, Vehicle Maintenance Garage & Fire Station, Golden, Jefferson County, CO

Uncertainties that flight crews and dispatchers must consider when calculating the fuel needed for a flight

NASA Technical Reports Server (NTRS)

Trujillo, Anna C.

1996-01-01

In 1993, fuel accounted for approximately 15 percent of an airline's expenses. Fuel consumption increases as fuel reserves increase because of the added weight to the aircraft. Calculating fuel reserves is a function of Federal Aviation Regulations, airline company policy, and factors that impact or are impacted by fuel usage enroute. This research studied how pilots and dispatchers determined the fuel needed for a flight and identified areas where improvements in methods may yield measurable fuel savings by (1) listing the uncertainties that contribute to adding contingency fuel, (2) obtaining the pilots' and dispatchers' perspective on how often each uncertainty occurred, and (3) obtaining pilots' and dispatchers' perspective on the fuel used for each occurrence. This study found that for the majority of the time, pilots felt that dispatchers included enough fuel. As for the uncertainties that flight crews and dispatchers account for, air traffic control accounts for 28% and weather uncertainties account for 58 percent. If improvements can be made in these two areas, a great potential exists to decrease the reserve required, and therefore, fuel usage without jeopardizing safety.

The Future Impact of Wind on BPA Power System Ancillary Services

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

Makarov, Yuri V.; Lu, Shuai; McManus, Bart

Wind power is growing in a very fast pace as an alternative generating resource. As the ratio of wind power over total system capacity increases, the impact of wind on various system aspects becomes significant. This paper presents a methodology to study the future impact of wind on BPA power system ancillary services including load following and regulation. Existing approaches for similar analysis include dispatch model simulation and standard deviation evaluation. The methodology proposed in this paper uses historical data and stochastic processes to simulate the load balancing processes in BPA power system. Then capacity, ramp rate and ramp durationmore » characteristics are extracted from the simulation results, and load following and regulation requirements are calculated accordingly. It mimics the actual power system operations therefore the results can be more realistic yet the approach is convenient to perform. Further, the ramp rate and ramp duration data obtained from the analysis can be used to evaluate generator response or maneuverability and energy requirement, respectively, additional to the capacity requirement.« less

Registered nurses' experiences of their decision-making at an Emergency Medical Dispatch Centre.

PubMed

Ek, Bosse; Svedlund, Marianne

2015-04-01

To describe registered nurses' experiences at an Emergency Medical Dispatch Centre. It is important that ambulances are urgently directed to patients who are in need of immediate help and of quick transportation to a hospital. Because resources are limited, Emergency Medical Dispatch centres cannot send ambulances with high priority to all callers. The efficiency of the system is therefore dependent on triage. Nurses worldwide are involved in patient triage, both before the patient's arrival to the hospital and in the subsequent emergency care. Ambulance dispatching is traditionally a duty for operators at Emergency Medical Dispatch centres, and in Sweden this duty has become increasingly performed by registered nurses. A qualitative design was used for this study. Fifteen registered nurses with experience at Emergency Medical Dispatch centres were interviewed. The participants were asked to describe the content of their work and their experiences. They also described the most challenging and difficult situations according to the critical incidence technique. Content analysis was used. Two themes emerged during the analysis: 'Having a profession with opportunities and obstacles' and 'Meeting serious and difficult situations', with eight sub-themes. The results showed that the decisions to dispatch ambulances were both challenging and difficult. Difficulties included conveying medical advice without seeing the patient, teaching cardio-pulmonary resuscitation via telephone and dealing with intoxicated and aggressive callers. Conflicts with colleagues and ambulance crews as well as fear of making wrong decisions were also mentioned. Work at Emergency Medical Dispatch centres is a demanding but stimulating duty for registered nurses. Great benefits can be achieved using experienced triage nurses, including increased patient safety and better use of medical resources. Improved internal support systems at Emergency Medical Dispatch centres and striving for a blame-free culture are important factors to attract and retain employees. © 2014 John Wiley & Sons Ltd.

Development of structural diagram of automated dispatch control system for power consumption at non-ferrous metallurgy enterprises

NASA Astrophysics Data System (ADS)

Klyuev, R. V.; Bosikov, I. I.; Madaeva, M. Z.; A-V Turluev, R.

2018-03-01

The structural scheme of the automated control system of power consumption at the industrial enterprise is developed in the article. At the non-ferrous metallurgy enterprise, an energy inspection and a rank analysis of the electrical energy consumption of the main processing equipment were carried out. It is established that the enterprises of non-ferrous metallurgy are a complex process system consisting of a set of thousands of jointly functioning technological facilities. For the most effective estimation of power consumption of enterprises, it is reasonable to use the automated system of dispatching control of power consumption (ASDCPC). The paper presents the results of the development of the ASDCPC structural diagram that allows one to perform on-line control and management of the energy and process parameters of the main production units and the enterprise as a whole. As a result of the introduction of ASDCPC at the non-ferrous metallurgy enterprise, the consumed active power was reduced during the peak hours of the load by 20%, the specific electricity consumption - by 14%, the cost of the energy component in the cost of production of hard alloys - by 3%.

Recommendations in dispatcher-assisted bystander resuscitation from emergency call center.

PubMed

García del Águila, J; López-Messa, J; Rosell-Ortiz, F; de Elías Hernández, R; Martínez del Valle, M; Sánchez-Santos, L; López-Herce, J; Cerdà-Vila, M; Roza-Alonso, C L; Bernardez-Otero, M

2015-01-01

Dispatch-assisted bystander cardiopulmonary resuscitation in out-of-hospital cardiac arrest has been shown as an effective measure to improve the survival of this process. The development of a unified protocol for all dispatch centers of the different emergency medical services can be a first step towards this goal in our environment. The process of developing a recommendations document and the realization of posters of dispatch-assisted cardiopulmonary resuscitation, agreed by different actors and promoted by the Spanish Resuscitation Council, is presented. Copyright © 2015 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.

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

Dias, F. G.; Luo, Y.; Mohanpurkar, M.

Since the modern-day introduction of plug-in electric vehicles (PEVs), scientists have proposed leveraging PEV battery packs as distributed energy resources for the electric grid. PEV charging can be controlled not only to provide energy for transportation but also to provide grid services and to facilitate the integration of renewable energy generation. With renewable generation increasing at an unprecedented rate, most of which is non-dispatchable and intermittent, the concept of using PEVs as controllable loads is appealing to electric utilities. This additional functionality could also provide value to PEV owners and drive PEV adoption. It has been widely proposed that PEVsmore » can provide valuable grid services, such as load shifting to provide voltage regulation. The objective this work is to address the degree to which PEVs can provide grid services and mutually benefit the electric utilities, PEV owners, and auto manufacturers.« less

Integrating Solar PV in Utility System Operations

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

Mills, A.; Botterud, A.; Wu, J.

2013-10-31

This study develops a systematic framework for estimating the increase in operating costs due to uncertainty and variability in renewable resources, uses the framework to quantify the integration costs associated with sub-hourly solar power variability and uncertainty, and shows how changes in system operations may affect these costs. Toward this end, we present a statistical method for estimating the required balancing reserves to maintain system reliability along with a model for commitment and dispatch of the portfolio of thermal and renewable resources at different stages of system operations. We estimate the costs of sub-hourly solar variability, short-term forecast errors, andmore » day-ahead (DA) forecast errors as the difference in production costs between a case with “realistic” PV (i.e., subhourly solar variability and uncertainty are fully included in the modeling) and a case with “well behaved” PV (i.e., PV is assumed to have no sub-hourly variability and can be perfectly forecasted). In addition, we highlight current practices that allow utilities to compensate for the issues encountered at the sub-hourly time frame with increased levels of PV penetration. In this analysis we use the analytical framework to simulate utility operations with increasing deployment of PV in a case study of Arizona Public Service Company (APS), a utility in the southwestern United States. In our analysis, we focus on three processes that are important in understanding the management of PV variability and uncertainty in power system operations. First, we represent the decisions made the day before the operating day through a DA commitment model that relies on imperfect DA forecasts of load and wind as well as PV generation. Second, we represent the decisions made by schedulers in the operating day through hour-ahead (HA) scheduling. Peaking units can be committed or decommitted in the HA schedules and online units can be redispatched using forecasts that are improved relative to DA forecasts, but still imperfect. Finally, we represent decisions within the operating hour by schedulers and transmission system operators as real-time (RT) balancing. We simulate the DA and HA scheduling processes with a detailed unit-commitment (UC) and economic dispatch (ED) optimization model. This model creates a least-cost dispatch and commitment plan for the conventional generating units using forecasts and reserve requirements as inputs. We consider only the generation units and load of the utility in this analysis; we do not consider opportunities to trade power with neighboring utilities. We also do not consider provision of reserves from renewables or from demand-side options. We estimate dynamic reserve requirements in order to meet reliability requirements in the RT operations, considering the uncertainty and variability in load, solar PV, and wind resources. Balancing reserve requirements are based on the 2.5th and 97.5th percentile of 1-min deviations from the HA schedule in a previous year. We then simulate RT deployment of balancing reserves using a separate minute-by-minute simulation of deviations from the HA schedules in the operating year. In the simulations we assume that balancing reserves can be fully deployed in 10 min. The minute-by-minute deviations account for HA forecasting errors and the actual variability of the load, wind, and solar generation. Using these minute-by-minute deviations and deployment of balancing reserves, we evaluate the impact of PV on system reliability through the calculation of the standard reliability metric called Control Performance Standard 2 (CPS2). Broadly speaking, the CPS2 score measures the percentage of 10-min periods in which a balancing area is able to balance supply and demand within a specific threshold. Compliance with the North American Electric Reliability Corporation (NERC) reliability standards requires that the CPS2 score must exceed 90% (i.e., the balancing area must maintain adequate balance for 90% of the 10-min periods). The combination of representing DA forecast errors in the DA commitments, using 1-min PV data to simulate RT balancing, and estimates of reliability performance through the CPS2 metric, all factors that are important to operating systems with increasing amounts of PV, makes this study unique in its scope.« less

Modelling utility-scale wind power plants. Part 1: Economics

NASA Astrophysics Data System (ADS)

Milligan, Michael R.

1999-10-01

As the worldwide use of wind turbine generators continues to increase in utility-scale applications, it will become increasingly important to assess the economic and reliability impact of these intermittent resources. Although the utility industry in the United States appears to be moving towards a restructured environment, basic economic and reliability issues will continue to be relevant to companies involved with electricity generation. This article is the first of two which address modelling approaches and results obtained in several case studies and research projects at the National Renewable Energy Laboratory (NREL). This first article addresses the basic economic issues associated with electricity production from several generators that include large-scale wind power plants. An important part of this discussion is the role of unit commitment and economic dispatch in production cost models. This paper includes overviews and comparisons of the prevalent production cost modelling methods, including several case studies applied to a variety of electric utilities. The second article discusses various methods of assessing capacity credit and results from several reliability-based studies performed at NREL.

Technical assistance for law-enforcement communications: Grant summary

NASA Technical Reports Server (NTRS)

Reilly, N. B.

1979-01-01

A summary overview of project activities and results are presented. The goals and objectives are reviewed and a description of the approaches used to attain them is given. The feedback received from the seminars conducted as part of the project, and results from a questionnaire about the project are included. Significant findings of the project in such areas as radio channel loading, dispatch system design, training and technology transfer are discussed. Several specific problem areas are identified and evaluated. Specific recommendations for future technical assistance efforts are presented along with an inventory of technical-assistance reports generated throughout the project.

Forecasting Electricity Prices in an Optimization Hydrothermal Problem

NASA Astrophysics Data System (ADS)

Matías, J. M.; Bayón, L.; Suárez, P.; Argüelles, A.; Taboada, J.

2007-12-01

This paper presents an economic dispatch algorithm in a hydrothermal system within the framework of a competitive and deregulated electricity market. The optimization problem of one firm is described, whose objective function can be defined as its profit maximization. Since next-day price forecasting is an aspect crucial, this paper proposes an efficient yet highly accurate next-day price new forecasting method using a functional time series approach trying to exploit the daily seasonal structure of the series of prices. For the optimization problem, an optimal control technique is applied and Pontryagin's theorem is employed.

Nuclear Hybrid Energy Systems Initial Integrated Case Study Development and Analysis

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

Harrison, Thomas J.; Greenwood, Michael Scott

The US Department of Energy Office of Nuclear Energy established the Nuclear Hybrid Energy System (NHES) project to develop a systematic, rigorous, technically accurate set of methods to model, analyze, and optimize the integration of dispatchable nuclear, fossil, and electric storage with an industrial customer. Ideally, the optimized integration of these systems will provide economic and operational benefits to the overall system compared to independent operation, and it will enhance the stability and responsiveness of the grid as intermittent, nondispatchable, renewable resources provide a greater share of grid power.

Barriers to dispatcher-assisted cardiopulmonary resuscitation in Singapore.

PubMed

Ho, Andrew Fu Wah; Sim, Zariel Jiaying; Shahidah, Nur; Hao, Ying; Ng, Yih Yng; Leong, Benjamin S H; Zarinah, Siti; Teo, Winston K L; Goh, Geraldine Shu Yi; Jaafar, Hamizah; Ong, Marcus E H

2016-08-01

Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) is effective in increasing bystander CPR in out-of-hospital cardiac arrests (OHCA). Singapore has recently implemented a DA-CPR program. We aimed to characterize barriers to commencement of chest compressions by callers in Singapore. We analyzed dispatch recordings of OHCA cases received by the ambulance call center between July 2012 and March 2015. Audio recordings of poor quality were excluded. Trained reviewers noted the sequential stages of the dispatcher's recognition of CPR, delivering CPR instructions and caller performing CPR. Time taken to reach these milestones was noted. Barriers to chest compressions were identified. A total of 4897 OHCA occurred during the study period, overall bystander CPR rate was 45.7%. 1885 dispatch recordings were reviewed with 1157 cases qualified for dispatcher CPR. In 1128 (97.5%) cases, the dispatcher correctly recognized the need for CPR. CPR instructions were delivered in 1056 (91.3%) cases. Of these, 1007 (87.0%) callers performed CPR to instruction. One or more barriers to chest compressions were identified in 430 (37.2%) cases. The commonest barrier identified was "could not move patient" (27%). Cases where barriers were identified were less likely to have the need for CPR recognized by the dispatcher (94.9% vs. 99.0%, p<0.001), CPR instructions given (79.3% vs. 98.3%, p<0.001) and CPR started (67.9% vs. 98.3%, p<0.001), while the time taken to reach each of these stages were significantly longer (p<0.001). Barriers were present in 37% of cases. They were associated with lower proportion of CPR started and longer delay to CPR. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Short-term Hydropower Reservoir Operations in Chile's Central Interconnected System: Tradeoffs between Hydrologic Alteration and Economic Performance

NASA Astrophysics Data System (ADS)

Olivares, M. A.

2011-12-01

Hydropower accounts for about 50% of the installed capacity in Chile's Central Interconnected System (CIS) and new developments are envisioned in the near future. Large projects involving reservoirs are perceived negatively by the general public. In terms of operations, hydropower scheduling takes place at monthly, weekly, daily and hourly intervals, and operations at each level affect different environmental processes. Due to its ability to quickly and inexpensively respond to short-term changes in demand, hydropower reservoirs often are operated to provide power during periods of peak demand. This operational scheme, known as hydropeaking, changes the hydrologic regime by altering the rate and frequency of changes in flow magnitude on short time scales. To mitigate impacts on downstream ecosystems, operational constraints -typically minimum instream flows and maximum ramping rates- are imposed on hydropower plants. These operational restrictions limit reduce operational flexibility and can reduce the economic value of energy generation by imposing additional costs on the operation of interconnected power systems. Methods to predict the degree of hydrologic alteration rely on statistical analyses of instream flow time series. Typically, studies on hydrologic alteration use historical operational records for comparison between pre- and post-dam conditions. Efforts to assess hydrologic alteration based on future operational schemes of reservoirs are scarce. This study couples two existing models: a mid-term operations planning and a short-term economic dispatch to simulate short-term hydropower reservoir operations under different future scenarios. Scenarios of possible future configurations of the Chilean CIS are defined with emphasis on the introduction of non-conventional renewables (particularly wind energy) and large hydropower projects in Patagonia. Both models try to reproduce the actual decision making process in the Chilean Central Interconnected System (CIS). Chile's CIS is structured as a mandatory pool with audited costs and therefore the economic dispatch can be formulated as a cost minimization problem. Consequently, hydropower reservoir operations are controlled by the ISO. Reservoirs with the most potential to cause short-term hydrologic alteration were identified from existing operational records. These records have also been used to validate our simulated operations. Results in terms of daily and subdaily hydrologic alteration as well as the economic performance of the CIS are presented for alternative energy matrix scenarios. Tradeoff curves representing the compromise between indicators of hydrologic alteration and economic indicators of the CIS operation are developed.

Operating health analysis of electric power systems

NASA Astrophysics Data System (ADS)

Fotuhi-Firuzabad, Mahmud

The required level of operating reserve to be maintained by an electric power system can be determined using both deterministic and probabilistic techniques. Despite the obvious disadvantages of deterministic approaches there is still considerable reluctance to apply probabilistic techniques due to the difficulty of interpreting a single numerical risk index and the lack of sufficient information provided by a single index. A practical way to overcome difficulties is to embed deterministic considerations in the probabilistic indices in order to monitor the system well-being. The system well-being can be designated as healthy, marginal and at risk. The concept of system well-being is examined and extended in this thesis to cover the overall area of operating reserve assessment. Operating reserve evaluation involves the two distinctly different aspects of unit commitment and the dispatch of the committed units. Unit commitment health analysis involves the determination of which unit should be committed to satisfy the operating criteria. The concepts developed for unit commitment health, margin and risk are extended in this thesis to evaluate the response well-being of a generating system. A procedure is presented to determine the optimum dispatch of the committed units to satisfy the response criteria. The impact on the response wellbeing being of variations in the margin time, required regulating margin and load forecast uncertainty are illustrated. The effects on the response well-being of rapid start units, interruptible loads and postponable outages are also illustrated. System well-being is, in general, greatly improved by interconnection with other power systems. The well-being concepts are extended to evaluate the spinning reserve requirements in interconnected systems. The interconnected system unit commitment problem is decomposed into two subproblems in which unit scheduling is performed in each isolated system followed by interconnected system evaluation. A procedure is illustrated to determine the well-being indices of the overall interconnected system. Under normal operating conditions, the system may also be able to carry a limited amount of interruptible load on top of its firm load without violating the operating criterion. An energy based approach is presented to determine the optimum interruptible load carrying capability in both the isolated and interconnected systems. Composite system spinning reserve assessment and composite system well-being are also examined in this research work. The impacts on the composite well-being of operating reserve considerations such as stand-by units, interruptible loads and the physical locations of these resources are illustrated. It is expected that the well-being framework and the concepts developed in this research work will prove extremely useful in the new competitive utility environment.

A Hybrid Genetic Programming Algorithm for Automated Design of Dispatching Rules.

PubMed

Nguyen, Su; Mei, Yi; Xue, Bing; Zhang, Mengjie

2018-06-04

Designing effective dispatching rules for production systems is a difficult and timeconsuming task if it is done manually. In the last decade, the growth of computing power, advanced machine learning, and optimisation techniques has made the automated design of dispatching rules possible and automatically discovered rules are competitive or outperform existing rules developed by researchers. Genetic programming is one of the most popular approaches to discovering dispatching rules in the literature, especially for complex production systems. However, the large heuristic search space may restrict genetic programming from finding near optimal dispatching rules. This paper develops a new hybrid genetic programming algorithm for dynamic job shop scheduling based on a new representation, a new local search heuristic, and efficient fitness evaluators. Experiments show that the new method is effective regarding the quality of evolved rules. Moreover, evolved rules are also significantly smaller and contain more relevant attributes.

Modeling and Simulation of Bus Dispatching Policy for Timed Transfers on Signalized Networks

NASA Astrophysics Data System (ADS)

Cho, Hsun-Jung; Lin, Guey-Shii

2007-12-01

The major work of this study is to formulate the system cost functions and to integrate the bus dispatching policy with signal control. The integrated model mainly includes the flow dispersion model for links, signal control model for nodes, and dispatching control model for transfer terminals. All such models are inter-related for transfer operations in one-center transit network. The integrated model that combines dispatching policies with flexible signal control modes can be applied to assess the effectiveness of transfer operations. It is found that, if bus arrival information is reliable, an early dispatching decision made at the mean bus arrival times is preferable. The costs for coordinated operations with slack times are relatively low at the optimal common headway when applying adaptive route control. Based on such findings, a threshold function of bus headway for justifying an adaptive signal route control under various time values of auto drivers is developed.

Secure provision of reactive power ancillary services in competitive electricity markets

NASA Astrophysics Data System (ADS)

El-Samahy, Ismael

The research work presented in this thesis discusses various complex issues associated with reactive power management and pricing in the context of new operating paradigms in deregulated power systems, proposing appropriate policy solutions. An integrated two-level framework for reactive power management is set forth, which is both suitable for a competitive market and ensures a secure and reliable operation of the associated power system. The framework is generic in nature and can be adopted for any electricity market structure. The proposed hierarchical reactive power market structure comprises two stages: procurement of reactive power resources on a seasonal basis, and real-time reactive power dispatch. The main objective of the proposed framework is to provide appropriate reactive power support from service providers at least cost, while ensuring a secure operation of the power system. The proposed procurement procedure is based on a two-step optimization model. First, the marginal benefits of reactive power supply from each provider, with respect to system security, are obtained by solving a loadability-maximization problem subject to transmission security constraints imposed by voltage and thermal limits. Second, the selected set of generators is determined by solving an optimal power flow (OPF)-based auction. This auction maximizes a societal advantage function comprising generators' offers and their corresponding marginal benefits with respect to system security, and considering all transmission system constraints. The proposed procedure yields the selected set of generators and zonal price components, which would form the basis for seasonal contracts between the system operator and the selected reactive power service providers. The main objective of the proposed reactive power dispatch model is to minimize the total payment burden on the Independent System Operator (ISO), which is associated with reactive power dispatch. The real power generation is decoupled and assumed to be fixed during the reactive power dispatch procedures; however, the effect of reactive power on real power is considered in the model by calculating the required reduction in real power output of a generator due to an increase in its reactive power supply. In this case, real power generation is allowed to be rescheduled, within given limits, from the already dispatched levels obtained from the energy market clearing process. The proposed dispatch model achieves the main objective of an ISO in a competitive electricity market, which is to provide the required reactive power support from generators at least cost while ensuring a secure operation of the power system. The proposed reactive power procurement and dispatch models capture both the technical and economic aspects of power system operation in competitive electricity markets; however, from an optimization point of view, these models represent non-convex mixed integer non-linear programming (MINLP) problems due to the presence of binary variables associated with the different regions of reactive power operation in a synchronous generator. Such MINLP optimization problems are difficult to solve, especially for an actual power system. A novel Generator Reactive Power Classification (GRPC) algorithm is proposed in this thesis to address this issue, with the advantage of iteratively solving the optimization models as a series of non-linear programming (NLP) sub-problems. The proposed reactive power procurement and dispatch models are implemented and tested on the CIGRE 32-bus system, with several case studies that represent different practical operating scenarios. The developed models are also compared with other approaches for reactive power provision, and the results demonstrate the robustness and effectiveness of the proposed model. The results clearly reveal the main features of the proposed models for optimal provision of reactive power ancillary service, in order to suit the requirements of an ISO under today's stressed system conditions in a competitive market environment.

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

Dall'Anese, Emiliano

Past works that focused on addressing power-quality and reliability concerns related to renewable energy resources (RESs) operating with business-as-usual practices have looked at the design of Volt/VAr and Volt/Watt strategies to regulate real or reactive powers based on local voltage measurements, so that terminal voltages are within acceptable levels. These control strategies have the potential of operating at the same time scale of distribution-system dynamics, and can therefore mitigate disturbances precipitated fast time-varying loads and ambient conditions; however, they do not necessarily guarantee system-level optimality, and stability claims are mainly based on empirical evidences. On a different time scale, centralizedmore » and distributed optimal power flow (OPF) algorithms have been proposed to compute optimal steady-state inverter setpoints, so that power losses and voltage deviations are minimized and economic benefits to end-users providing ancillary services are maximized. However, traditional OPF schemes may offer decision making capabilities that do not match the dynamics of distribution systems. Particularly, during the time required to collect data from all the nodes of the network (e.g., loads), solve the OPF, and subsequently dispatch setpoints, the underlying load, ambient, and network conditions may have already changed; in this case, the DER output powers would be consistently regulated around outdated setpoints, leading to suboptimal system operation and violation of relevant electrical limits. The present work focuses on the synthesis of distributed RES-inverter controllers that leverage the opportunities for fast feedback offered by power-electronics interfaced RESs. The overarching objective is to bridge the temporal gap between long-term system optimization and real-time control, to enable seamless RES integration in large scale with stability and efficiency guarantees, while congruently pursuing system-level optimization objectives. The design of the control framework is based on suitable linear approximations of the AC power-flow equations as well as Lagrangian regularization methods. The proposed controllers enable an update of the power outputs at a time scale that is compatible with the underlying dynamics of loads and ambient conditions, and continuously drive the system operation towards OPF-based solutions.« less

Information processing in an urban fire department communication system.

PubMed

Siegel, J; Weitzman, D O

1975-09-01

One of the most important functions of any fire department is to provide selective contact with fire fighting units and to dispatch these units based on information gathered from street alarm boxes and telephones. This paper is concerned with the problem of dispatching tactical response information to remote fire fighting units and with the effect of workload on the dispatch function.

Real-time OHT Dispatching Mechanism for the Interbay Automated Material Handling System with Shortcuts and Bypasses

NASA Astrophysics Data System (ADS)

Pan, Cong; Zhang, Jie; Qin, Wei

2017-05-01

As a key to improve the performance of the interbay automated material handling system (AMHS) in 300 mm semiconductor wafer fabrication system, the real-time overhead hoist transport (OHT) dispatching problem has received much attention. This problem is first formulated as a special form of assignment problem and it is proved that more than one solution will be obtained by Hungarian algorithm simultaneously. Through proposing and strictly proving two propositions related to the characteristics of these solutions, a modified Hungarian algorithm is designed to distinguish these solutions. Finally, a new real-time OHT dispatching method is carefully designed by implementing the solution obtained by the modified Hungarian algorithm. The experimental results of discrete event simulations show that, compared with conventional Hungarian algorithm dispatching method, the proposed dispatching method that chooses the solution with the maximum variance respectively reduces on average 4 s of the average waiting time and average lead time of wafer lots, and its performance is rather stable in multiple different scenarios of the interbay AMHS with different quantities of shortcuts. This research provides an efficient real-time OHT dispatching mechanism for the interbay AMHS with shortcuts and bypasses.

Do emergency medical services dispatch nature and severity codes agree with paramedic field findings?

PubMed

Neely, K W; Eldurkar, J A; Drake, M E

2000-02-01

Emergency medical services (EMS) systems increasingly seek to triage patients to alternative EMS resources. Emergency medical services dispatchers may be asked to perform this triage. New protocols may be necessary. Alternatively, existing protocols may be sufficient for this task. For an existing dispatch protocol to be sufficient, it at least must accurately categorize patient condition and severity based on an external standard. To examine the extent to which nature codes (NCs), or patient condition codes, and severity codes (SCs) currently assigned in one urban 911 center agree with paramedic field findings. The null hypothesis was that there is no routine agreement (75%) between dispatcher-assigned NC or SC and paramedic-assigned NC or SC for the same patient using the same protocol. Emergency medical services dispatch nature and severity code data and matching out-of-hospital data were prospectively gathered over six months. Dispatch data included the NC: caller-identified problem, and the SC: dispatcher-assessed severity. Each NC is modified by one of three SCs (1, 3, or 9): 1 is emergent, 3 is urgent, and 9 is neither. Paramedics verified and/or corrected dispatcher-assigned NCs and SCs using the same dispatch protocol. One thousand forty usable cases fell into 33 unique NC/SC combinations. The designation of SC 1 was assigned 275 times, SC 3 was assigned 736 times, and SC 9 was assigned 24 times. The SC was missing five times. The overall NC agreement was 0.70 (95% CI = 0.697 to 0.703). The overall SC agreement was 0.65 (95% CI = 0.645 to 0.655). The NC agreement exceeded 75% for ten (59%) NC/SC combinations. The SC agreement exceeded 75% for five (29%) NC/SC combinations. There was both NC and SC agreement for four (24%) combinations: urgent breathing problems, urgent diabetic problems, urgent falls, and urgent overdoses. The greatest NC/SC disagreement occurred within emergent and urgent traffic crashes. Paramedics adjusted SC toward lower severity 29% of the time and toward higher severity 5.4% of the time. There was no upward SC adjustment for eight (47%) combinations. Certain dispatcher-assigned NC and SC codes and NC/SC combinations achieved the study threshold. Overall agreement failed to achieve the threshold. The lowest SC level was rarely assigned, preventing a meaningful analysis of all severity levels.

Hospital-Confirmed Acute Myocardial Infarction: Prehospital Identification Using the Medical Priority Dispatch System.

PubMed

Clawson, Jeff J; Gardett, Isabel; Scott, Greg; Fivaz, Conrad; Barron, Tracey; Broadbent, Meghan; Olola, Christopher

2018-02-01

Introduction Early recognition of an acute myocardial infarction (AMI) can increase the patient's likelihood of survival. As the first point of contact for patients accessing medical care through emergency services, emergency medical dispatchers (EMDs) represent the earliest potential identification point for AMIs. The objective of the study was to determine how AMI cases were coded and prioritized at the dispatch point, and also to describe the distribution of these cases by patient age and gender. Hypothesis/Problem No studies currently exist that describe the EMD's ability to correctly triage AMIs into Advanced Life Support (ALS) response tiers. The retrospective descriptive study utilized data from three sources: emergency medical dispatch, Emergency Medical Services (EMS), and emergency departments (EDs)/hospitals. The primary outcome measure was the distributions of AMI cases, as categorized by Chief Complaint Protocol, dispatch priority code and level, and patient age and gender. The EMS and ED/hospital data came from the Utah Department of Health (UDoH), Salt Lake City, Utah. Dispatch data came from two emergency communication centers covering the entirety of Salt Lake City and Salt Lake County, Utah. Overall, 89.9% of all the AMIs (n=606) were coded in one of the three highest dispatch priority levels, all of which call for ALS response (called CHARLIE, DELTA, and ECHO in the studied system). The percentage of AMIs significantly increased for patients aged 35 years and older, and varied significantly by gender, dispatch level, and chief complaint. A total of 85.7% of all deaths occurred among patients aged 55 years and older, and 88.9% of the deaths were handled in the ALS-recommended priority levels. Acute myocardial infarctions may present as a variety of clinical symptoms, and the study findings demonstrated that more than one-half were identified as having chief complaints of Chest Pain or Breathing Problems at the dispatch point, followed by Sick Person and Unconscious/Fainting. The 35-year age cutoff for assignment to higher priority levels is strongly supported. The Falls and Sick Person Protocols offer opportunities to capture atypical AMI presentations. Clawson JJ , Gardett I , Scott G , Fivaz C , Barron T , Broadbent M , Olola C . Hospital-confirmed acute myocardial infarction: prehospital identification using the Medical Priority Dispatch System. Prehosp Disaster Med. 2018;33(1):29-35.

Feasibility of a computer-assisted feedback system between dispatch centre and ambulances.

PubMed

Lindström, Veronica; Karlsten, Rolf; Falk, Ann-Charlotte; Castrèn, Maaret

2011-06-01

The aim of the study was to evaluate the feasibility of a newly developed computer-assisted feedback system between dispatch centre and ambulances in Stockholm, Sweden. A computer-assisted feedback system based on a Finnish model was designed to fit the Swedish emergency medical system. Feedback codes were identified and divided into three categories; assessment of patients' primary condition when ambulance arrives at scene, no transport by the ambulance and level of priority. Two ambulances and one emergency medical communication centre (EMCC) in Stockholm participated in the study. A sample of 530 feedback codes sent through the computer-assisted feedback system was reviewed. The information on the ambulance medical records was compared with the feedback codes used and 240 assignments were further analyzed. The used feedback codes sent from ambulance to EMCC were correct in 92% of the assignments. The most commonly used feedback code sent to the emergency medical dispatchers was 'agree with the dispatchers' assessment'. In addition, in 160 assignments there was a mismatch between emergency medical dispatchers and ambulance nurse assessments. Our results have shown a high agreement between medical dispatchers and ambulance nurse assessment. The feasibility of the feedback codes seems to be acceptable based on the small margin of error. The computer-assisted feedback system may, when used on a daily basis, make it possible for the medical dispatchers to receive feedback in a structural way. The EMCC organization can directly evaluate any changes in the assessment protocol by structured feedback sent from the ambulance.

Dispatcher-assisted compression-only cardiopulmonary resuscitation provides best quality cardiopulmonary resuscitation by laypersons: A randomised controlled single-blinded manikin trial.

PubMed

Spelten, Oliver; Warnecke, Tobias; Wetsch, Wolfgang A; Schier, Robert; Böttiger, Bernd W; Hinkelbein, Jochen

2016-08-01

High-quality cardiopulmonary resuscitation (CPR) by laypersons is a key determinant of both outcome and survival for out-of-hospital cardiac arrest. Dispatcher-assisted CPR (telephone-CPR, T-CPR) increases the frequency and correctness of bystander-CPR but results in prolonged time to first chest compressions. However, it remains unclear whether instructions for rescue ventilation and/or chest compressions should be recommended for dispatcher-assisted CPR. The aim of this study was to evaluate both principles of T-CPR with respect to CPR quality. Randomised controlled single-blinded manikin trial. University Hospital of Cologne, Germany, 1 July 2012 to 30 September 2012. Sixty laypersons between 18 and 65 years. Medically educated individuals, medical professionals and pregnant women were excluded. Participants were asked to resuscitate a manikin and were randomised into three groups: not dispatcher-assisted (uninstructed) CPR (group 1; U-CPR; n = 20), dispatcher-assisted compression-only CPR (group 2; DACO-CPR; n = 19) and full dispatcher-assisted CPR with rescue ventilation (group 3; DAF-CPR; n = 19). Specific parameters of CPR quality [i.e. no-flow-time (NFT) as well as compression and ventilation parameters] were analysed. To compare different groups we used Student's t test and P less than 0.05 was considered significant. Initial NFT was lowest in the DACO-CPR group (mean 21.3 ± 14.4%), followed by dispatcher-assisted full CPR (mean 49.1 ± 8.5%) and by unassisted CPR (mean 55.0 ± 12.9%). Initial NFT covering the time of instruction was lower in DACO-CPR (12.1 ± 5.4%) as compared to dispatcher-assisted full CPR (20.7 ± 8.1%). Compression depth was similar in all three groups: 40.6 ± 13.0 mm (unassisted CPR), 41.0 ± 12.2 mm (DACO-CPR) and 38.8 ± 15.8 mm (dispatcher-assisted full CPR). Average compression frequency was highest in the DACO-CPR group (65.2 ± 22.4 min) compared with the unassisted CPR group (35.6 ± 24.2 min) and the dispatcher-assisted full CPR group (44.5 ± 10.8 min). Correct rescue ventilation was given in 3.1 ± 11.1% (unassisted CPR) and 1.6 ± 16.1% (dispatcher-assisted full CPR) of all ventilation attempts. Best quality of CPR was achieved by DACO-CPR because of superior compression frequencies and reduced NFT. In contrast, the full dispatcher-assisted CPR with a longer initial instructing phase (initial NFT) did not result in enhanced CPR quality or an optimised compression depth.

An Approximate Dynamic Programming Mode for Optimal MEDEVAC Dispatching

DTIC Science & Technology

2015-03-26

over the myopic policy. This indicates the ADP policy is efficiently managing resources by 28 not immediately sending the nearest available MEDEVAC...DISPATCHING THESIS Presented to the Faculty Department of Operational Sciences Graduate School of Engineering and Management Air Force Institute of Technology...medical evacuation (MEDEVAC) dispatch policies. To solve the MDP, we apply an ap- proximate dynamic programming (ADP) technique. The problem of deciding

Generating short-term probabilistic wind power scenarios via nonparametric forecast error density estimators: Generating short-term probabilistic wind power scenarios via nonparametric forecast error density estimators

DOE PAGES

Staid, Andrea; Watson, Jean -Paul; Wets, Roger J. -B.; ...

2017-07-11

Forecasts of available wind power are critical in key electric power systems operations planning problems, including economic dispatch and unit commitment. Such forecasts are necessarily uncertain, limiting the reliability and cost effectiveness of operations planning models based on a single deterministic or “point” forecast. A common approach to address this limitation involves the use of a number of probabilistic scenarios, each specifying a possible trajectory of wind power production, with associated probability. We present and analyze a novel method for generating probabilistic wind power scenarios, leveraging available historical information in the form of forecasted and corresponding observed wind power timemore » series. We estimate non-parametric forecast error densities, specifically using epi-spline basis functions, allowing us to capture the skewed and non-parametric nature of error densities observed in real-world data. We then describe a method to generate probabilistic scenarios from these basis functions that allows users to control for the degree to which extreme errors are captured.We compare the performance of our approach to the current state-of-the-art considering publicly available data associated with the Bonneville Power Administration, analyzing aggregate production of a number of wind farms over a large geographic region. Finally, we discuss the advantages of our approach in the context of specific power systems operations planning problems: stochastic unit commitment and economic dispatch. Here, our methodology is embodied in the joint Sandia – University of California Davis Prescient software package for assessing and analyzing stochastic operations strategies.« less

Quantifying the Economic and Grid Reliability Impacts of Improved Wind Power Forecasting

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

Wang, Qin; Martinez-Anido, Carlo Brancucci; Wu, Hongyu

Wind power forecasting is an important tool in power system operations to address variability and uncertainty. Accurately doing so is important to reducing the occurrence and length of curtailment, enhancing market efficiency, and improving the operational reliability of the bulk power system. This research quantifies the value of wind power forecasting improvements in the IEEE 118-bus test system as modified to emulate the generation mixes of Midcontinent, California, and New England independent system operator balancing authority areas. To measure the economic value, a commercially available production cost modeling tool was used to simulate the multi-timescale unit commitment (UC) and economicmore » dispatch process for calculating the cost savings and curtailment reductions. To measure the reliability improvements, an in-house tool, FESTIV, was used to calculate the system's area control error and the North American Electric Reliability Corporation Control Performance Standard 2. The approach allowed scientific reproducibility of results and cross-validation of the tools. A total of 270 scenarios were evaluated to accommodate the variation of three factors: generation mix, wind penetration level, and wind fore-casting improvements. The modified IEEE 118-bus systems utilized 1 year of data at multiple timescales, including the day-ahead UC, 4-hour-ahead UC, and 5-min real-time dispatch. The value of improved wind power forecasting was found to be strongly tied to the conventional generation mix, existence of energy storage devices, and the penetration level of wind energy. The simulation results demonstrate that wind power forecasting brings clear benefits to power system operations.« less

Generating short-term probabilistic wind power scenarios via nonparametric forecast error density estimators: Generating short-term probabilistic wind power scenarios via nonparametric forecast error density estimators

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

Staid, Andrea; Watson, Jean -Paul; Wets, Roger J. -B.

Forecasts of available wind power are critical in key electric power systems operations planning problems, including economic dispatch and unit commitment. Such forecasts are necessarily uncertain, limiting the reliability and cost effectiveness of operations planning models based on a single deterministic or “point” forecast. A common approach to address this limitation involves the use of a number of probabilistic scenarios, each specifying a possible trajectory of wind power production, with associated probability. We present and analyze a novel method for generating probabilistic wind power scenarios, leveraging available historical information in the form of forecasted and corresponding observed wind power timemore » series. We estimate non-parametric forecast error densities, specifically using epi-spline basis functions, allowing us to capture the skewed and non-parametric nature of error densities observed in real-world data. We then describe a method to generate probabilistic scenarios from these basis functions that allows users to control for the degree to which extreme errors are captured.We compare the performance of our approach to the current state-of-the-art considering publicly available data associated with the Bonneville Power Administration, analyzing aggregate production of a number of wind farms over a large geographic region. Finally, we discuss the advantages of our approach in the context of specific power systems operations planning problems: stochastic unit commitment and economic dispatch. Here, our methodology is embodied in the joint Sandia – University of California Davis Prescient software package for assessing and analyzing stochastic operations strategies.« less

Introducing systematic dispatcher-assisted cardiopulmonary resuscitation (telephone-CPR) in a non-Advanced Medical Priority Dispatch System (AMPDS): implementation process and costs.

PubMed

Dami, Fabrice; Fuchs, Vincent; Praz, Laurent; Vader, John-Paul

2010-07-01

In order to improve the quality of our Emergency Medical Services (EMS), to raise bystander cardiopulmonary resuscitation rates and thereby meet what is becoming a universal standard in terms of quality of emergency services, we decided to implement systematic dispatcher-assisted or telephone-CPR (T-CPR) in our medical dispatch center, a non-Advanced Medical Priority Dispatch System. The aim of this article is to describe the implementation process, costs and results following the introduction of this new "quality" procedure. This was a prospective study. Over an 8-week period, our EMS dispatchers were given new procedures to provide T-CPR. We then collected data on all non-traumatic cardiac arrests within our state (Vaud, Switzerland) for the following 12 months. For each event, the dispatchers had to record in writing the reason they either ruled out cardiac arrest (CA) or did not propose T-CPR in the event they did suspect CA. All emergency call recordings were reviewed by the medical director of the EMS. The analysis of the recordings and the dispatchers' written explanations were then compared. During the 12-month study period, a total of 497 patients (both adults and children) were identified as having a non-traumatic cardiac arrest. Out of this total, 203 cases were excluded and 294 cases were eligible for T-CPR. Out of these eligible cases, dispatchers proposed T-CPR on 202 occasions (or 69% of eligible cases). They also erroneously proposed T-CPR on 17 occasions when a CA was wrongly identified (false positive). This represents 7.8% of all T-CPR. No costs were incurred to implement our study protocol and procedures. This study demonstrates it is possible, using a brief campaign of sensitization but without any specific training, to implement systematic dispatcher-assisted cardiopulmonary resuscitation in a non-Advanced Medical Priority Dispatch System such as our EMS that had no prior experience with systematic T-CPR. The results in terms of T-CPR delivery rate and false positive are similar to those found in previous studies. We found our results satisfying the given short time frame of this study. Our results demonstrate that it is possible to improve the quality of emergency services at moderate or even no additional costs and this should be of interest to all EMS that do not presently benefit from using T-CPR procedures. EMS that currently do not offer T-CPR should consider implementing this technique as soon as possible, and we expect our experience may provide answers to those planning to incorporate T-CPR in their daily practice.

Reserve valuation in electric power systems

NASA Astrophysics Data System (ADS)

Ruiz, Pablo Ariel

Operational reliability is provided in part by scheduling capacity in excess of the load forecast. This reserve capacity balances the uncertain power demand with the supply in real time and provides for equipment outages. Traditionally, reserve scheduling has been ensured by enforcing reserve requirements in the operations planning. An alternate approach is to employ a stochastic formulation, which allows the explicit modeling of the sources of uncertainty. This thesis compares stochastic and reserve methods and evaluates the benefits of a combined approach for the efficient management of uncertainty in the unit commitment problem. Numerical studies show that the unit commitment solutions obtained for the combined approach are robust and superior with respect to the traditional approach. These robust solutions are especially valuable in areas with a high proportion of wind power, as their built-in flexibility allows the dispatch of practically all the available wind power while minimizing the costs of operation. The scheduled reserve has an economic value since it reduces the outage costs. In several electricity markets, reserve demand functions have been implemented to take into account the value of reserve in the market clearing process. These often take the form of a step-down function at the reserve requirement level, and as such they may not appropriately represent the reserve value. The value of reserve is impacted by the reliability, dynamic and stochastic characteristics of system components, the system operation policies, and the economic aspects such as the risk preferences of the demand. In this thesis, these aspects are taken into account to approximate the reserve value and construct reserve demand functions. Illustrative examples show that the demand functions constructed have similarities with those implemented in some markets.

Improving emergency medical dispatching with emphasis on mass-casualty incidents.

PubMed

Kleinoscheg, Gabriel; Burgsteiner, Harald; Bernroider, Martin; Kiechle, Günter; Obermayer, Maria

2014-01-01

Dispatching ambulances is a demanding and stressful task for dispatchers. This is especially true in case of mass-casualty incidents. Therefore, the aim of this work was to investigate if and to what extent the dispatch operation of the Red Cross Salzburg can be optimized on such occasions with a computerized system. The basic problem of a dynamic multi-vehicle Dial-a-Ride Problem with time windows was enhanced according to the requirements of the Red Cross Salzburg. The general objective was to minimize the total mileage covered by ambulances and the waiting time of patients. Furthermore, in case of emergencies suitable adaptions to a plan should be carried out automatically. Consequently, the problem is solved by using the Adaptive Large Neighborhood Search. Evaluation results indicate that the system outperforms a human dispatcher by between 2.5% and 36% within 1 minute of runtime concerning total costs. Moreover, the system's response time in case that a plan has to be updated is less than 1 minute on average.

HOMER: The hybrid optimization model for electric renewable

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

Lilienthal, P.; Flowers, L.; Rossmann, C.

1995-12-31

Hybrid renewable systems are often more cost-effective than grid extensions or isolated diesel generators for providing power to remote villages. There are a wide variety of hybrid systems being developed for village applications that have differing combinations of wind, photovoltaics, batteries, and diesel generators. Due to variations in loads and resources determining the most appropriate combination of these components for a particular village is a difficult modelling task. To address this design problem the National Renewable Energy Laboratory has developed the Hybrid Optimization Model for Electric Renewables (HOMER). Existing models are either too detailed for screening analysis or too simplemore » for reliable estimation of performance. HOMER is a design optimization model that determines the configuration, dispatch, and load management strategy that minimizes life-cycle costs for a particular site and application. This paper describes the HOMER methodology and presents representative results.« less

Hierarchical control framework for integrated coordination between distributed energy resources and demand response

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

Wu, Di; Lian, Jianming; Sun, Yannan

Demand response is representing a significant but largely untapped resource that can greatly enhance the flexibility and reliability of power systems. In this paper, a hierarchical control framework is proposed to facilitate the integrated coordination between distributed energy resources and demand response. The proposed framework consists of coordination and device layers. In the coordination layer, various resource aggregations are optimally coordinated in a distributed manner to achieve the system-level objectives. In the device layer, individual resources are controlled in real time to follow the optimal power generation or consumption dispatched from the coordination layer. For the purpose of practical applications,more » a method is presented to determine the utility functions of controllable loads by taking into account the real-time load dynamics and the preferences of individual customers. The effectiveness of the proposed framework is validated by detailed simulation studies.« less

Examining the Fundamental Obstructs of Adopting Cloud Computing for 9-1-1 Dispatch Centers in the USA

ERIC Educational Resources Information Center

Osman, Abdulaziz

2016-01-01

The purpose of this research study was to examine the unknown fears of embracing cloud computing which stretches across measurements like fear of change from leaders and the complexity of the technology in 9-1-1 dispatch centers in USA. The problem that was addressed in the study was that many 9-1-1 dispatch centers in USA are still using old…

Solar hybrid power plants: Solar energy contribution in reaching full dispatchability and firmness

NASA Astrophysics Data System (ADS)

Servert, Jorge F.; López, Diego; Cerrajero, Eduardo; Rocha, Alberto R.; Pereira, Daniel; Gonzalez, Lucía

2016-05-01

Renewable energies for electricity generation have always been considered as a risk for the electricity system due to its lack of dispatchability and firmness. Renewable energies penetration is constrained to strong grids or else its production must be limited to ensure grid stability, which is kept by the usage of hydropower energy or fossil-fueled power plants. CSP technology has an opportunity to arise not only as a dispatchable and firm technology, but also as an alternative that improves grid stability. To achieve that objective, solar hybrid configurations are being developed, being the most representative three different solutions: SAPG, ISCC and HYSOL. A reference scenario in Kingdom of Saudi Arabia (KSA) has been defined to compare these solutions, which have been modelled, simulated and evaluated in terms of dispatchability and firmness using ratios defined by the authors. The results show that: a) SAPG obtains the highest firmness KPI values, but no operation constraints have been considered for the coal boiler and the solar energy contribution is limited to 1.7%, b) ISCC provides dispatchable and firm electricity production but its solar energy contribution is limited to a 6.4%, and c) HYSOL presents the higher solar energy contribution of all the technologies considered: 66.0% while providing dispatchable and firm generation in similar conditions as SAPG and ISCC.

Optimal Dispatch of Unreliable Electric Grid-Connected Diesel Generator-Battery Power Systems

NASA Astrophysics Data System (ADS)

Xu, D.; Kang, L.

2015-06-01

Diesel generator (DG)-battery power systems are often adopted by telecom operators, especially in semi-urban and rural areas of developing countries. Unreliable electric grids (UEG), which have frequent and lengthy outages, are peculiar to these regions. DG-UEG-battery power system is an important kind of hybrid power system. System dispatch is one of the key factors to hybrid power system integration. In this paper, the system dispatch of a DG-UEG-lead acid battery power system is studied with the UEG of relatively ample electricity in Central African Republic (CAR) and UEG of poor electricity in Congo Republic (CR). The mathematical models of the power system and the UEG are studied for completing the system operation simulation program. The net present cost (NPC) of the power system is the main evaluation index. The state of charge (SOC) set points and battery bank charging current are the optimization variables. For the UEG in CAR, the optimal dispatch solution is SOC start and stop points 0.4 and 0.5 that belong to the Micro-Cycling strategy and charging current 0.1 C. For the UEG in CR, the optimal dispatch solution is of 0.1 and 0.8 that belongs to the Cycle-Charging strategy and 0.1 C. Charging current 0.1 C is suitable for both grid scenarios compared to 0.2 C. It makes the dispatch strategy design easier in commercial practices that there are a few very good candidate dispatch solutions with system NPC values close to that of the optimal solution for both UEG scenarios in CAR and CR.

The appropriateness of emergency medical service responses in the eThekwini district of KwaZulu-Natal, South Africa.

PubMed

Newton, P R; Naidoo, R; Brysiewicz, P

2015-09-19

 Emergency medical services (EMS) are sometimes required to respond to cases that are later found not to be emergencies, resulting in high levels of inappropriate responses. This study evaluated the extent to which this occurs.  All cases dispatched over 72 hours by the eThekwini EMS in Durban, South Africa, were prospectively enrolled in a quantitative descriptive study. Vehicle control forms containing dispatch data were matched and compared with patient report forms containing epidemiological and clinical data to describe the nature and extent of inappropriate responses based on patient need. Data were subjected to simple descriptive analysis, correlations and χ2 testing.  A total of 1 385 cases met the study inclusion criteria. Marked variations existed between dispatch and on-scene priority settings, most notably in the highest priority 'red-code' category, which constituted >56% of cases dispatched yet accounted for <2% at the scene (p<0.001). Conversely, >80% of 'red-code' dispatches required a lower priority response. When comparing resource allocation according to patient interventional needs, >58% of cases required either no intervention or transport only and almost 36% required basic life support intervention only (p<0.001). Moreover, <12% of advanced life support dispatches were for patients found to be 'red code' at the scene.  There is a significant mismatch between the dispatch of EMS resources and actual patient need in the eThekwini district, with significantly high levels of inappropriate emergency responses.

Paediatric medical emergency calls to a Danish Emergency Medical Dispatch Centre: a retrospective, observational study.

PubMed

Andersen, Kasper; Mikkelsen, Søren; Jørgensen, Gitte; Zwisler, Stine Thorhauge

2018-01-05

Little is known regarding paediatric medical emergency calls to Danish Emergency Medical Dispatch Centres (EMDC). This study aimed to investigate these calls, specifically the medical issues leading to them and the pre-hospital units dispatched to the paediatric emergencies. We performed a retrospective, observational study on paediatric medical emergency calls managed by the EMDC in the Region of Southern Denmark in February 2016. We reviewed audio recordings of emergency calls and ambulance records to identify calls concerning patients ≤ 15 years. We examined EMDC dispatch records to establish how the medical issues leading to these calls were classified and which pre-hospital units were dispatched to the paediatric emergencies. We analysed the data using descriptive statistics. Of a total of 7052 emergency calls in February 2016, 485 (6.9%) concerned patients ≤ 15 years. We excluded 19 and analysed the remaining 466. The reported medical issues were commonly classified as: "seizures" (22.1%), "sick child" (18.9%) and "unclear problem" (12.9%). The overall most common pre-hospital response was immediate dispatch of an ambulance with sirens and lights with a supporting physician-manned mobile emergency care unit (56.4%). The classification of medical issues and the dispatched pre-hospital units varied with patient age. We believe our results might help focus the paediatric training received by emergency medical dispatch staff on commonly encountered medical issues, such as the symptoms and conditions pertaining to the symptom categories "seizures" and "sick child". Furthermore, the results could prove useful in hypothesis generation for future studies examining paediatric medical emergency calls. Almost 7% of all calls concerned patients ≤ 15 years. Medical issues pertaining to the symptom categories "seizures", "sick child" and "unclear problem" were common and the calls commonly resulted in urgent pre-hospital responses.

Stress and salivary cortisol in emergency medical dispatchers: A randomized shifts control trial

PubMed Central

Bedini, Sarah; Braun, François; Weibel, Laurence; Aussedat, Michel; Pereira, Bruno; Dutheil, Frédéric

2017-01-01

Stress at work is a public health concern. Phone operators in emergency medical dispatch centers are particularly at risk. We aimed to demonstrate that the most stressful time for emergency medical dispatchers is the shift when they receive emergency incoming calls, with cortisol as a biomarker of stress. For each emergency medical dispatcher, we measured outcomes over a control day and during three types of shift: Incoming emergency call, Dispatch and Re-assessment. The pattern of shifts was randomized. Saliva was sampled every 15 minutes for 2 hours, i.e. 6 consecutive times, starting 15 minutes after the first life-and-death incoming emergency call between 2 and 5 pm during three types of shift. We measured saliva cortisol every 2 hours over a control day, from 7am to 9pm. Perceived stress was assessed by a visual analog scale. We recruited 22 phone operators aged 36.4+/-10.8 years old (14 women and 8 men). Cortisol values were higher during the Incoming emergency call shift than during the Dispatch (p = .04) and Re-assessment (p = .04) shifts. The increase in cortisol levels was greater in men than in women (p = .009). There were no differences between control values and those of the three shifts. The kinetics of cortisol increased with greater perceived stress overall (p < .001) and for each type of shift (Incoming emergency call, p = .02; Dispatch p = .03; Re-assessment: p < .001). The kinetics of cortisol in response to incoming emergency calls was greater when the call was an absolute emergency (p = .03), and also tended to further increase when a subsequent absolute incoming emergency call was received (p = 0.07). In conclusion, the incoming emergency call shift carries particular risk for dispatchers, who have greater perceived stress and a greater increase in cortisol levels. PMID:28505199

Stress and salivary cortisol in emergency medical dispatchers: A randomized shifts control trial.

PubMed

Bedini, Sarah; Braun, François; Weibel, Laurence; Aussedat, Michel; Pereira, Bruno; Dutheil, Frédéric

2017-01-01

Stress at work is a public health concern. Phone operators in emergency medical dispatch centers are particularly at risk. We aimed to demonstrate that the most stressful time for emergency medical dispatchers is the shift when they receive emergency incoming calls, with cortisol as a biomarker of stress. For each emergency medical dispatcher, we measured outcomes over a control day and during three types of shift: Incoming emergency call, Dispatch and Re-assessment. The pattern of shifts was randomized. Saliva was sampled every 15 minutes for 2 hours, i.e. 6 consecutive times, starting 15 minutes after the first life-and-death incoming emergency call between 2 and 5 pm during three types of shift. We measured saliva cortisol every 2 hours over a control day, from 7am to 9pm. Perceived stress was assessed by a visual analog scale. We recruited 22 phone operators aged 36.4+/-10.8 years old (14 women and 8 men). Cortisol values were higher during the Incoming emergency call shift than during the Dispatch (p = .04) and Re-assessment (p = .04) shifts. The increase in cortisol levels was greater in men than in women (p = .009). There were no differences between control values and those of the three shifts. The kinetics of cortisol increased with greater perceived stress overall (p < .001) and for each type of shift (Incoming emergency call, p = .02; Dispatch p = .03; Re-assessment: p < .001). The kinetics of cortisol in response to incoming emergency calls was greater when the call was an absolute emergency (p = .03), and also tended to further increase when a subsequent absolute incoming emergency call was received (p = 0.07). In conclusion, the incoming emergency call shift carries particular risk for dispatchers, who have greater perceived stress and a greater increase in cortisol levels.

Multi-Fluid Geo-Energy Systems for Bulk and Thermal Energy Storage and Dispatchable Renewable and Low-Carbon Electricity

NASA Astrophysics Data System (ADS)

Buscheck, T. A.; Randolph, J.; Saar, M. O.; Hao, Y.; Sun, Y.; Bielicki, J. M.

2014-12-01

Integrating renewable energy sources into electricity grids requires advances in bulk and thermal energy storage technologies, which are currently expensive and have limited capacity. We present an approach that uses the huge fluid and thermal storage capacity of the subsurface to harvest, store, and dispatch energy from subsurface (geothermal) and surface (solar, nuclear, fossil) thermal resources. CO2 captured from fossil-energy systems and N2 separated from air are injected into permeable formations to store pressure, generate artesian flow of brine, and provide additional working fluids. These enable efficient fluid recirculation, heat extraction, and power conversion, while adding operational flexibility. Our approach can also store and dispatch thermal energy, which can be used to levelize concentrating solar power and mitigate variability of wind and solar power. This may allow low-carbon, base-load power to operate at full capacity, with the stored excess energy being available to addresss diurnal and seasonal mismatches between supply and demand. Concentric rings of horizontal injection and production wells are used to create a hydraulic divide to store pressure, CO2, N2, and thermal energy. Such storage can take excess power from the grid and excess thermal energy, and dispatch that energy when it is demanded. The system is pressurized and/or heated when power supply exceeds demand and depressurized when demand exceeds supply. Supercritical CO2 and N2 function as cushion gases to provide enormous pressure-storage capacity. Injecting CO2 and N2 displaces large quantities of brine, reducing the use of fresh water. Geologic CO2 storage is a crucial option for reducing CO2 emissions, but valuable uses for CO2 are needed to justify capture costs. The initial "charging" of our system requires permanently isolating large volumes of CO2 from the atmosphere and thus creates a market for its disposal. Our approach is designed for locations where a permeable geologic formation is overlain by an impermeable formation that constrains migration of buoyant CO2 and/or N2, and heated brine. Such geologic conditions exist over nearly half of the contiguous United States. This work was performed under the auspices of the U.S. DOE by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Evaluation of a binary optimization approach to find the optimum locations of energy storage devices in a power grid with stochastically varying loads and wind generation

NASA Astrophysics Data System (ADS)

Dar, Zamiyad

The prices in the electricity market change every five minutes. The prices in peak demand hours can be four or five times more than the prices in normal off peak hours. Renewable energy such as wind power has zero marginal cost and a large percentage of wind energy in a power grid can reduce the price significantly. The variability of wind power prevents it from being constantly available in peak hours. The price differentials between off-peak and on-peak hours due to wind power variations provide an opportunity for a storage device owner to buy energy at a low price and sell it in high price hours. In a large and complex power grid, there are many locations for installation of a storage device. Storage device owners prefer to install their device at locations that allow them to maximize profit. Market participants do not possess much information about the system operator's dispatch, power grid, competing generators and transmission system. The publicly available data from the system operator usually consists of Locational Marginal Prices (LMP), load, reserve prices and regulation prices. In this thesis, we develop a method to find the optimum location of a storage device without using the grid, transmission or generator data. We formulate and solve an optimization problem to find the most profitable location for a storage device using only the publicly available market pricing data such as LMPs, and reserve prices. We consider constraints arising due to storage device operation limitations in our objective function. We use binary optimization and branch and bound method to optimize the operation of a storage device at a given location to earn maximum profit. We use two different versions of our method and optimize the profitability of a storage unit at each location in a 36 bus model of north eastern United States and south eastern Canada for four representative days representing four seasons in a year. Finally, we compare our results from the two versions of our method with a multi period stochastically optimized economic dispatch of the same power system with storage device at locations proposed by our method. We observe a small gap in profit values arising due to the effect of storage device on market prices. However, we observe that the ranking of different locations in terms of profitability remains almost unchanged. This leads us to conclude that our method can successfully predict the optimum locations for installation of storage units in a complex grid using only the publicly available electricity market data.

Real-Time, Wide Area Dispatch of Mobil Tank Trucks

DTIC Science & Technology

1987-01-01

human dispatchers it assists. Using CAD, Mobil has substantially re- duced costs and staff while improving customer service. I n the spring of 1985, a...process by establishing the Mobil order response center (MORC). To use MORC, the customer dials a toll-free number, available 24 hours a day, seven...MATS Figwe 3: Mobil light products order and dispatch information flow. Customers call an audio re- sponse computer system named MORC ( Mobil order

Clean Energy Generation and Dispatch in Reformed Wholesale Electricity Markets: Experience in the United States

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

Zhou, Shengru; Hurlbut, David J; Li, Ma

In recent years, the US electricity market has undergone several stages of reform, and gradually formed the market where the wholesale electricity price is determined by the supply and demand. The US electricity market also changes along with the rapid development of clean energy, forming a number of the market mechanisms that is specifically developed for clean energy power generation characteristics. On the basis of discussing the pricing mechanism of US electricity market, this paper analyzes the experience and practice of encouraging renewable energy development policy and clean energy dispatch from the angle of market mechanism and dispatching decision, andmore » puts forward the reference for clean energy dispatching in China.« less

ERDA/NASA 100 kilowatt mod-o wind turbine operations and performance. [at the NASA Plum Brook Station, Ohio

NASA Technical Reports Server (NTRS)

Thomas, R. L.; Richards, T. R.

1977-01-01

The ERDA/NASA 100 kW Mod-0 wind turbine is operating at the NASA Plum Brook Station near Sandusky, Ohio. The operation of the wind turbine has been fully demonstrated and includes start-up, synchronization to the utility network, blade pitch control for control of power and speed, and shut-down. Also, fully automatic operation has been demonstrated by use of a remote control panel, 50 miles from the site, similar to what a utility dispatcher might use. The operation systems and experience with the wind turbine loads, electrical power and aerodynamic performance obtained from testing are described.

[Stress management for office workers].

PubMed

Hayashi, Takeshi

2002-09-01

The environment which surrounds office workers has undergone a big transformation with the collapse of lifetime employment, the shift from the long employment principle to meritocracy, the results principle, the introduction of flexible work hours, outsourcing and dispatch work. Today's office worker stressor include 1. VDT work, 2. meritocracy, 3. management by objective, 4. excessive load on the middle and advanced age generations, 5. the collapse of the lifetime employment system and 6. non-employee changes. (1) VDT work management, (2) the use of Information technology, (3) Improvement of office environments, (4) Management of long overtime work and (5) Support of superiors and colleagues are thought as stress management.

Optimizing Storage and Renewable Energy Systems with REopt

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

Elgqvist, Emma M.; Anderson, Katherine H.; Cutler, Dylan S.

Under the right conditions, behind the meter (BTM) storage combined with renewable energy (RE) technologies can provide both cost savings and resiliency. Storage economics depend not only on technology costs and avoided utility rates, but also on how the technology is operated. REopt, a model developed at NREL, can be used to determine the optimal size and dispatch strategy for BTM or off-grid applications. This poster gives an overview of three applications of REopt: Optimizing BTM Storage and RE to Extend Probability of Surviving Outage, Optimizing Off-Grid Energy System Operation, and Optimizing Residential BTM Solar 'Plus'.

Preferences and concerns of potential users in the selection of solar thermal systems for industrial and small utility applications

NASA Astrophysics Data System (ADS)

Gresham, J. B.; Kriz, T. A.

1981-03-01

To achieve widespread application in the industrial and utility sectors, solar systems must be economically competitive. Economic viability is, in turn, determined by a number of supporting criteria, ranging from system reliability to dispatch characteristics to how the system supports the main product line. In addition, solar systems possess some inherent attributes that may render some of the traditional supporting criteria inappropriate or require their redefinition. Those criteria and their relation to the solar investments are discussed in three steps. First, the main concerns and preferences of the potential users, as identified in recent SERI studies, are identified. Second, the equitability of the resulting decision criteria for solar investments are examined. Finally, the implications of these criteria for solar energy's penetration into these markets are discussed.

Pre-recorded instructional audio vs. dispatchers' conversational assistance in telephone cardiopulmonary resuscitation: A randomized controlled simulation study.

PubMed

Birkun, Alexei; Glotov, Maksim; Ndjamen, Herman Franklin; Alaiye, Esther; Adeleke, Temidara; Samarin, Sergey

2018-01-01

To assess the effectiveness of the telephone chest-compression-only cardiopulmonary resuscitation (CPR) guided by a pre-recorded instructional audio when compared with dispatcher-assisted resuscitation. It was a prospective, blind, randomised controlled study involving 109 medical students without previous CPR training. In a standardized mannequin scenario, after the step of dispatcher-assisted cardiac arrest recognition, the participants performed compression-only resuscitation guided over the telephone by either: (1) the pre-recorded instructional audio ( n =57); or (2) verbal dispatcher assistance ( n =52). The simulation video records were reviewed to assess the CPR performance using a 13-item checklist. The interval from call reception to the first compression, total number and rate of compressions, total number and duration of pauses after the first compression were also recorded. There were no significant differences between the recording-assisted and dispatcher-assisted groups based on the overall performance score (5.6±2.2 vs. 5.1±1.9, P >0.05) or individual criteria of the CPR performance checklist. The recording-assisted group demonstrated significantly shorter time interval from call receipt to the first compression (86.0±14.3 vs. 91.2±14.2 s, P <0.05), higher compression rate (94.9±26.4 vs. 89.1±32.8 min -1 ) and number of compressions provided (170.2±48.0 vs. 156.2±60.7). When provided by untrained persons in the simulated settings, the compression-only resuscitation guided by the pre-recorded instructional audio is no less efficient than dispatcher-assisted CPR. Future studies are warranted to further assess feasibility of using instructional audio aid as a potential alternative to dispatcher assistance.

Predictive Ability of an Emergency Medical Dispatch Stroke Diagnostic Tool in Identifying Hospital-Confirmed Strokes.

PubMed

Clawson, Jeff J; Scott, Greg; Gardett, Isabel; Youngquist, Scott; Taillac, Peter; Fivaz, Conrad; Olola, Christopher

2016-08-01

Early hospital notification of a possible stroke arriving via emergency medical services (EMS) can prepare stroke center personnel for timely treatment, especially timely administration of tissue plasminogen activator. Stroke center notification from the emergency dispatch center-before responders reach the scene-may promote even earlier and faster system activation, meaning that stroke center teams may be ready to receive patients as soon as the ambulance arrives. This study evaluates the use of a Medical Priority Dispatch System (MPDS; Priority Dispatch Corp., Salt Lake City, UT) Stroke Diagnostic Tool (SDxT) to identify possible strokes early by comparing the tools' results to on-scene and hospital findings. The retrospective descriptive study utilized stroke data from 3 sources: emergency medical dispatch, EMS, and emergency department/hospital. A total of 830 cases were collected between June 2012 and December 2013, of which 603 (72.7%) had matching dispatch records. Of the 603 cases, 304 (50.4%) were handled using MPDS Stroke Protocol 28. The SDxT had an 86.4% ability (OR [95% CI]: 2.3 [1.5, 3.5]) to effectively identify strokes among all the hospital-confirmed stroke cases (sensitivity), and a 26.6% ability to effectively identify nonstrokes among all the hospital-confirmed nonstroke cases (specificity). The SDxT demonstrated a very high sensitivity, compared to similar tools used in the field and at dispatch. The specificity was somewhat low, but this was expected-and is intended in the creation of protocols to be used over the phone in emergency situations. The tool is a valuable method for identifying strokes early and may allow early hospital notification. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

A novel protocol for dispatcher assisted CPR improves CPR quality and motivation among rescuers-A randomized controlled simulation study.

PubMed

Rasmussen, Stinne Eika; Nebsbjerg, Mette Amalie; Krogh, Lise Qvirin; Bjørnshave, Katrine; Krogh, Kristian; Povlsen, Jonas Agerlund; Riddervold, Ingunn Skogstad; Grøfte, Thorbjørn; Kirkegaard, Hans; Løfgren, Bo

2017-01-01

Emergency dispatchers use protocols to instruct bystanders in cardiopulmonary resuscitation (CPR). Studies changing one element in the dispatcher's protocol report improved CPR quality. Whether several changes interact is unknown and the effect of combining multiple changes previously reported to improve CPR quality into one protocol remains to be investigated. We hypothesize that a novel dispatch protocol, combining multiple beneficial elements improves CPR quality compared with a standard protocol. A novel dispatch protocol was designed including wording on chest compressions, using a metronome, regular encouragements and a 10-s rest each minute. In a simulated cardiac arrest scenario, laypersons were randomized to perform single-rescuer CPR guided with the novel or the standard protocol. a composite endpoint of time to first compression, hand position, compression depth and rate and hands-off time (maximum score: 22 points). Afterwards participants answered a questionnaire evaluating the dispatcher assistance. The novel protocol (n=61) improved CPR quality score compared with the standard protocol (n=64) (mean (SD): 18.6 (1.4)) points vs. 17.5 (1.7) points, p<0.001. The novel protocol resulted in deeper chest compressions (mean (SD): 58 (12)mm vs. 52 (13)mm, p=0.02) and improved rate of correct hand position (61% vs. 36%, p=0.01) compared with the standard protocol. In both protocols hands-off time was short. The novel protocol improved motivation among rescuers compared with the standard protocol (p=0.002). Participants guided with a standard dispatch protocol performed high quality CPR. A novel bundle of care protocol improved CPR quality score and motivation among rescuers. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Evaluating the CO 2 emissions reduction potential and cost of power sector re-dispatch

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

Steinberg, Daniel C.; Bielen, David A.; Townsend, Aaron

Prior studies of the U.S. electricity sector have recognized the potential to reduce carbon dioxide (CO2) emissions by substituting generation from coal-fired units with generation from under-utilized and lower-emitting natural gas-fired units; in fact, this type of 're-dispatch' was invoked as one of the three building blocks used to set the emissions targets under the Environmental Protection Agency's Clean Power Plan. Despite the existence of surplus natural gas capacity in the U.S., power system operational constraints not often considered in power sector policy analyses, such as transmission congestion, generator ramping constraints, minimum generation constraints, planned and unplanned generator outages, andmore » ancillary service requirements, could limit the potential and increase the cost of coal-to-gas re-dispatch. Using a highly detailed power system unit commitment and dispatch model, we estimate the maximum potential for re-dispatch in the Eastern Interconnection, which accounts for the majority of coal capacity and generation in the U.S. Under our reference assumptions, we find that maximizing coal-to-gas re-dispatch yields emissions reductions of 230 million metric tons (Mt), or 13% of power sector emissions in the Eastern Interconnection, with a corresponding average abatement cost of $15-$44 per metric ton of CO2, depending on the assumed supply elasticity of natural gas.« less

Interior view of Dispatch Office and counter, facing south ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior view of Dispatch Office and counter, facing south - International Longshoremen's & Warehousemen's Union Hall, Naval Civil Engineering Laboratory, Port Hueneme Road, Port Hueneme, Ventura County, CA

76 FR 29335 - Qualification, Service, and Use of Crewmembers and Aircraft Dispatchers

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-20

...On January 12, 2009, the FAA published a notice of proposed rulemaking on qualification, service, and use of crewmembers and aircraft dispatchers. Because of the complexity of the issues and the concerns raised by commenters, the FAA is issuing this supplemental notice of proposed rulemaking. The FAA proposes to amend the regulations for crewmember and aircraft dispatcher training programs in domestic, flag, and supplemental operations. The proposed regulations enhance traditional training programs by requiring the use of flight simulation training devices for flightcrew members and including additional training and evaluation requirements for all crewmembers and aircraft dispatchers in areas that are critical to safety. The proposal also reorganizes and revises the qualification, training, and evaluation requirements. The proposed changes are intended to contribute significantly to reducing aviation accidents.

Greening the Grid: Pathways to Integrate 175 Gigawatts of Renewable Energy into India’s Electric Grid, Vol. 1. National Study

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

Palchak, David; Cochran, Jaquelin; Deshmukh, Ranjit

The use of renewable energy (RE) sources, primarily wind and solar generation, is poised to grow significantly within the Indian power system. The Government of India has established a target of 175 gigawatts (GW) of installed RE capacity by 2022, including 60 GW of wind and 100 GW of solar, up from 29 GW wind and 9 GW solar at the beginning of 2017. Using advanced weather and power system modeling made for this project, the study team is able to explore operational impacts of meeting India’s RE targets and identify actions that may be favorable for integration. Our primarymore » tool is a detailed production cost model, which simulates optimal scheduling and dispatch of available generation in a future year (2022) by minimizing total production costs subject to physical, operational, and market constraints. Our team comprises a core group from the Power System Operation Corporation, Ltd. (POSOCO), which is the national grid operator (with representation from the National, Southern, and Western Regional Load Dispatch Centers) under Ministry of Power, National Renewable Energy Laboratory (NREL), and Lawrence Berkeley National Laboratory (Berkeley Lab), and a broader modeling team that includes Central Electricity Authority (CEA), POWERGRID (the central transmission utility, CTU), and State Load Dispatch Centers in Maharashtra, Gujarat, Tamil Nadu, Karnataka, Rajasthan, and Andhra Pradesh. Our model includes high-resolution wind and solar data (forecasts and actuals), unique properties for each generator, CEA/CTU’s anticipated buildout of the power system, and enforced state-to-state transmission flows. Assuming the fulfillment of current efforts to provide better access to the physical flexibility of the power system, we find that power system balancing with 100 GW of solar and 60 GW of wind is achievable at 15-minute operational timescales with minimal RE curtailment. This RE capacity meets 22% of total projected 2022 electricity consumption in India with annual RE curtailment of 1.4%, in line with experiences in other countries with significant RE penetrations (Bird et al. 2016). Changes to operational practice can further reduce the cost of operating the power system and reduce RE curtailment. Coordinating scheduling and dispatch over a broader area is the largest driver to reduce costs, saving INR 6300 crore (USD 980 million) annually when optimized regionally. Lowering minimum operating levels of coal plants (from 70% to 40%) is the biggest driver to reduce RE curtailment—from 3.5% down to 0.76%. In fact, this operating property is more influential than faster thermal generation ramp rates in lowering the projected levels of curtailment. While this study does not answer every question relevant to planning for India’s 2022 RE targets, it is an important step toward analyzing operational challenges and cost saving opportunities using state-of-the-art power system planning tools. Further analysis can build upon this basis to explore optimal renewable resource and intrastate transmission siting, system stability during contingencies, and the influence of total power system investment costs on customer tariffs.« less

Greening the Grid: Pathways to Integrate 175 Gigawatts of Renewable Energy into India's Electric Grid, Vol. I -- National Study

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

Palchak, David; Cochran, Jaquelin; Ehlen, Ali

The use of renewable energy (RE) sources, primarily wind and solar generation, is poised to grow significantly within the Indian power system. The Government of India has established a target of 175 gigawatts (GW) of installed RE capacity by 2022, including 60 GW of wind and 100 GW of solar, up from 29 GW wind and 9 GW solar at the beginning of 2017. Thanks to advanced weather and power system modeling made for this project, the study team is able to explore operational impacts of meeting India's RE targets and identify actions that may be favorable for integration. Ourmore » primary tool is a detailed production cost model, which simulates optimal scheduling and dispatch of available generation in a future year (2022) by minimizing total production costs subject to physical, operational, and market constraints. Our team comprises a core group from the Power System Operation Corporation, Ltd. (POSOCO), which is the national grid operator (with representation from the National, Southern, and Western Regional Load Dispatch Centers) under Ministry of Power, National Renewable Energy Laboratory (NREL), and Lawrence Berkeley National Laboratory (LBNL), and a broader modeling team that includes Central Electricity Authority (CEA), POWERGRID (the central transmission utility, CTU), and State Load Dispatch Centers in Maharashtra, Gujarat, Tamil Nadu, Karnataka, Rajasthan, and Andhra Pradesh. Our model includes high-resolution wind and solar data (forecasts and actuals), unique properties for each generator, CEA/CTU's anticipated buildout of the power system, and enforced state-to-state transmission flows. Assuming the fulfillment of current efforts to provide better access to the physical flexibility of the power system, we find that power system balancing with 100 GW of solar and 60 GW of wind is achievable at 15-minute operational timescales with minimal RE curtailment. This RE capacity meets 22% of total projected 2022 electricity consumption in India with annual RE curtailment of 1.4%, in line with experiences in other countries with significant RE penetrations (Bird et al. 2016). Changes to operational practice can further reduce the cost of operating the power system and reduce RE curtailment. Coordinating scheduling and dispatch over a broader area is the largest driver to reduce costs, saving INR 6300 crore (USD $920 million) annually when optimized regionally. Lowering minimum operating levels of coal plants (from 70% to 40%) is the biggest driver to reduce RE curtailment - from 3.5% down to 0.76%. In fact, this operating property is more influential than faster thermal generation ramp rates in lowering the projected levels of curtailment. While this study does not answer every question relevant to planning for India's 2022 RE targets, it is an important step toward analyzing operational challenges and cost saving opportunities using state-of-the-art power system planning tools. Further analysis can build upon this basis to explore optimal renewable resource and intrastate transmission siting, system stability during contingencies, and the influence of total power system investment costs on customer tariffs.« less

Engineering the Implementation of Pumped Hydro Energy Storage in the Arizona Power Grid

NASA Astrophysics Data System (ADS)

Dixon, William Jesse J.

This thesis addresses the issue of making an economic case for bulk energy storage in the Arizona bulk power system. Pumped hydro energy storage (PHES) is used in this study. Bulk energy storage has often been suggested for large scale electric power systems in order to levelize load (store energy when it is inexpensive [energy demand is low] and discharge energy when it is expensive [energy demand is high]). It also has the potential to provide opportunities to avoid transmission and generation expansion, and provide for generation reserve margins. As the level of renewable energy resources increases, the uncertainty and variability of wind and solar resources may be improved by bulk energy storage technologies. For this study, the MATLab software platform is used, a mathematical based modeling language, optimization solvers (specifically Gurobi), and a power flow solver (PowerWorld) are used to simulate an economic dispatch problem that includes energy storage and transmission losses. A program is created which utilizes quadratic programming to analyze various cases using a 2010 summer peak load from the Arizona portion of the Western Electricity Coordinating Council (WECC) system. Actual data from industry are used in this test bed. In this thesis, the full capabilities of Gurobi are not utilized (e.g., integer variables, binary variables). However, the formulation shown here does create a platform such that future, more sophisticated modeling may readily be incorporated. The developed software is used to assess the Arizona test bed with a low level of energy storage to study how the storage power limit effects several optimization outputs such as the system wide operating costs. Large levels of energy storage are then added to see how high level energy storage affects peak shaving, load factor, and other system applications. Finally, various constraint relaxations are made to analyze why the applications tested eventually approach a constant value. This research illustrates the use of energy storage which helps minimize the system wide generator operating cost by "shaving" energy off of the peak demand. The thesis builds on the work of another recent researcher with the objectives of strengthening the assumptions used, checking the solutions obtained, utilizing higher level simulation languages to affirm results, and expanding the results and conclusions. One important point not fully discussed in the present thesis is the impact of efficiency in the pumped hydro cycle. The efficiency of the cycle for modern units is estimated at higher than 90%. Inclusion of pumped hydro losses is relegated to future work.

Interior detail of dispatch boards in main hall, facing west ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior detail of dispatch boards in main hall, facing west - International Longshoremen's & Warehousemen's Union Hall, Naval Civil Engineering Laboratory, Port Hueneme Road, Port Hueneme, Ventura County, CA

Flair-fleet location and information reporting

NASA Technical Reports Server (NTRS)

Norman, E. R.; Dunlap, M. E.

1974-01-01

The FLAIR system, as now produced, automatically updates each vehicle's location and corresponding officer's status once each two seconds and presents this information to police dispatchers in the command and control center. The position of all vehicles available for assignment is displayed on a color video map at each dispatcher's console to an accuracy of 50 feet. This gives the dispatcher a continuous picture of the deployment of the total available force and thus complete command and control of all police under his responsibility.

An Overview of the Automated Dispatch Controller Algorithms in the System Advisor Model (SAM)

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

DiOrio, Nicholas A

2017-11-22

Three automatic dispatch modes have been added to the battery model within the System Adviser Model. These controllers have been developed to perform peak shaving in an automated fashion, providing users with a way to see the benefit of reduced demand charges without manually programming a complicated dispatch control. A flexible input option allows more advanced interaction with the automated controller. This document will describe the algorithms in detail and present brief results on its use and limitations.

The Analysis and Discussion in the Effective Application of the Dispatcher Training Based on Case Teaching Method with the Cause from the Action of the Gap Protection of Main Transformer

NASA Astrophysics Data System (ADS)

Yuanyuan, Xu; Zhengmao, Zhang; Xiang, Fang; Yuanshuai, Xu; Xinxin, Song

2018-03-01

The combination of theory and practice is a difficult problem on dispatcher training. Through a typical example of case, this paper provides an effective case teaching method for dispatcher training, and combines the theoretical discussion of the rule of experience with cases and achieves vividness. It helps students to understand and catch the key points of the theory, and improve their practical skills.

Stem Inc. SunShot Incubator Program Final Technical Report

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

Butterfield, Karen

In this Energy Storage Control Algorithms project, Stem sought to develop tools and control algorithms to increase the value and reduce balance-of-system and grid integration costs associated with adding distributed solar generation to the grid. These advances fell under the headings SolarScope and SolarController. Stem sought to create initial market traction with a fully commercialized product for the solar industry to size storage systems (SolarScope) as well as a solar intermittency-mitigation framework for utilities (SolarController) in the course of the project. The company sought to align strategic growth plans and enable the rollout of the products to broader audiences inmore » multiple geographic regions by leveraging the major solar companies in the national market as partners. Both final products were both intended to be commercialized. They are: SolarScope: Analysis tool to identify viable PV + storage projects and thereby expedite the sales and interconnection processes. SolarScope combines customer load data, PV production estimates, utility rate tariff, and simulated storage into a simple user interface for PV developers. Developers can easily identify viable solar + storage sites without the need for complex and time consuming, site-by-site spreadsheet modeling. SolarContoller: Tool to autonomously dispatch distributed storage in order to mitigate voltage fluctuation and reduce curtailment. SolarController co-optimizes, in real time, storage dispatch for circuit stability and curtailment reduction, enabling higher penetrations of PV. SolarController is automated, not requiring utility dispatch or management, as Stem hardware senses grid voltage, frequency, customer load, PV production, and power factor. In the end the two products met with different outcomes. SolarScope was tested by potential users, and continues to be used as a foundational platform for partnership with key solar industry partners. SolarController, on the other hand, was successful in lab testing but was not commercialized due to a lack of marketability and lack of interested customer base. Together the development of these two products marked a material step forward for Stem; and a new milestone along the pathway of integration for the solar and storage industries. SolarScope is leading to real, out-of-the-lab project development in storage + solar for the commercial customer sector. Meanwhile SolarController has opened the eyes of regulators and utility executives alike to the potential of distributed solar and by doing so, has moved the conversation forward for the integration of distributed energy resources more broadly on the grid.« less

Review for the Korean Health Professionals and International Cooperation Doctors Dispatched to Peru by the Korea International Cooperation Agency (KOICA).

PubMed

Kim, Bongyoung

2015-04-01

South Korea dispatches Korean nationals to partner developing countries as an Official Development Assistance (ODA) project through the Korea International Cooperation Agency (KOICA). In the health sector, KOICA dispatches international cooperation doctors (ICDs), nurses, physical therapists, radiologic technologists, nutritionists, medical laboratory technologists, occupational therapists, and dental hygienists. A total of 216 ICDs were dispatched over 19 times from 1995 until 2013. There were 19 areas of specialties among the ICDs. The most common specialty was internal medicine (61/216, 28.2%), the second most common specialty was general surgery (43/216, 19.9%), followed by oriental medicine (27/216, 12.5%), pediatrics (17/216, 7.9%), orthopedics (16/216, 7.4%), family medicine (16/216, 7.4%), and odontology (14/216, 6.5%). The ICDs have worked in 21 countries. KOICA dispatched the highest number of ICDs to Asia (97/216, 44.9%), followed by Africa (50/216, 23.1%), Latin America (34/216, 15.7%), the commonwealth of independent states (31/216, 14.4%), and Oceania (4/216, 1.9%). Nobody was dispatched to the Middle East. A total of 134 KOICA health professionals were dispatched to Peru from 1996 until October 1, 2014. Of these, 19.4% (26/134) were ICDs, 44.8% (60/216) were nurses, 20.1% (27/134) were physical therapists, 6.7% (9/134) were radiologic technologists, 2.2% (3/134) were nutritionists, and 6.7% (9/134) were medical laboratory. ICDs' specialties comprised internal medicine (13/26, 50%), family medicine (8/26, 30.8%), pediatrics (2/26, 7.7%), otorhinolaryngology (1/26, 3.8%), orthopedics (1/26, 3.8%), and oriental medicine (1/26, 3.8%). Most of the dispatched health professionals worked at institutions that were supported by KOICA. For this reason, the proportion of health professionals who worked at public health centers (PHCs) was the highest (58.2%, 78/134) when classified by workplace type. Other KOICA health professionals worked at hospitals, governmental organizations (GOs), or schools.

Minimizing Uncertainties Impact in Decision Making with an Applicability Study for Economic Power Dispatch

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

Wang, Hong; Wang, Shaobu; Fan, Rui

This report summaries the work performed under the LDRD project on the preliminary study on knowledge automation, where specific focus has been made on the investigation of the impact of uncertainties of human decision making onto the optimization of the process operation. At first the statistics on signals from the Brain-Computing Interface (BCI) is analyzed so as to obtain the uncertainties characterization of human operators during the decision making phase using the electroencephalogram (EEG) signals. This is then followed by the discussions of an architecture that reveals the equivalence between optimization and closed loop feedback control design, where it hasmore » been shown that all the optimization problems can be transferred into the control design problem for closed loop systems. This has led to a “closed loop” framework, where the structure of the decision making is shown to be subjected to both process disturbances and controller’s uncertainties. The latter can well represent the uncertainties or randomness occurred during human decision making phase. As a result, a stochastic optimization problem has been formulated and a novel solution has been proposed using probability density function (PDF) shaping for both the cost function and the constraints using stochastic distribution control concept. A sufficient condition has been derived that guarantees the convergence of the optimal solution and discussions have been made for both the total probabilistic solution and chanced constrained optimization which have been well-studied in optimal power flows (OPF) area. A simple case study has been carried out for the economic dispatch of powers for a grid system when there are distributed energy resources (DERs) in the system, and encouraging results have been obtained showing that a significant savings on the generation cost can be expected.« less

26 CFR 49.4253-5 - Exemption for items otherwise taxed.

Code of Federal Regulations, 2011 CFR

2011-04-01

... otherwise taxed. A dispatch, message, or conversation transmitted by toll telephone, telegraph, or... considered to be one dispatch, message, or conversation, and is subject to only one payment of tax under...

26 CFR 49.4253-5 - Exemption for items otherwise taxed.

Code of Federal Regulations, 2010 CFR

2010-04-01

... otherwise taxed. A dispatch, message, or conversation transmitted by toll telephone, telegraph, or... considered to be one dispatch, message, or conversation, and is subject to only one payment of tax under...

Efficient dispatching in a terminal city network

DOT National Transportation Integrated Search

2001-01-01

This report describes new optimization and simulation tools to address several problems in transportation, specifically driver dispatching and tour formation in full truckload trucking. In this segment of transportation industry, one of the problems ...

Best practices in bus dispatch.

DOT National Transportation Integrated Search

2012-06-01

In 2007, the National Center for Transit Research (NCTR) sponsored a study to examine best practices in : extraboard operator management. In most transit agencies, extraboard manpower is managed by the : dispatch function, but extraboard management i...

Evaluation of Human Reliability in Selected Activities in the Railway Industry

NASA Astrophysics Data System (ADS)

Sujová, Erika; Čierna, Helena; Molenda, Michał

2016-09-01

The article focuses on evaluation of human reliability in the human - machine system in the railway industry. Based on a survey of a train dispatcher and of selected activities, we have identified risk factors affecting the dispatcher`s work and the evaluated risk level of their influence on the reliability and safety of preformed activities. The research took place at the authors` work place between 2012-2013. A survey method was used. With its help, authors were able to identify selected work activities of train dispatcher's risk factors that affect his/her work and the evaluated seriousness of its influence on the reliability and safety of performed activities. Amongst the most important finding fall expressions of unclear and complicated internal regulations and work processes, a feeling of being overworked, fear for one's safety at small, insufficiently protected stations.

Robust optimization-based DC optimal power flow for managing wind generation uncertainty

NASA Astrophysics Data System (ADS)

Boonchuay, Chanwit; Tomsovic, Kevin; Li, Fangxing; Ongsakul, Weerakorn

2012-11-01

Integrating wind generation into the wider grid causes a number of challenges to traditional power system operation. Given the relatively large wind forecast errors, congestion management tools based on optimal power flow (OPF) need to be improved. In this paper, a robust optimization (RO)-based DCOPF is proposed to determine the optimal generation dispatch and locational marginal prices (LMPs) for a day-ahead competitive electricity market considering the risk of dispatch cost variation. The basic concept is to use the dispatch to hedge against the possibility of reduced or increased wind generation. The proposed RO-based DCOPF is compared with a stochastic non-linear programming (SNP) approach on a modified PJM 5-bus system. Primary test results show that the proposed DCOPF model can provide lower dispatch cost than the SNP approach.

Cluster analyses of association of weather, daily factors and emergent medical conditions.

PubMed

Malkić, Jasmin; Sarajlić, Nermin; Smrke, Barbara U R; Smrke, Dragica

2013-03-01

The goal of this study was to evaluate associations between the meteorological conditions and the number of emergency cases for five distinctive causes of dispatch groups reported to SOS dispatch centre in Uppsala, Sweden. Center's responsibility include alerting to 17 ambulances in whole Uppsala County, area of 8,209 km2 with around 320,000 inhabitants representing the target patient group. Source of the medical data for this study is the database of dispatch data for the year of 2009, while the metrological data have been provided from Uppsala University Department of Earth Sciences yearly weather report. Medical and meteorological data were summoned into the unified data space where each point represents a day with its weather parameters and dispatch cause group cardinality. DBSCAN data mining algorithm was implemented to five distinctive groups of dispatch causes after the data spaces have gone through the variance adjustment and the principal component analyses. As the result, several point clusters were discovered in each of the examined data spaces indicating the distinctive conditions regarding the weather and daily cardinality of the dispatch cause, as well as the associations between these two. Most interesting finding is that specific type of winter weather formed a cluster only around the days with the high count of breathing difficulties, while one of the summer weather clusters made similar association with the days with low number of cases. Findings were confirmed by confidence level estimation based on signal to noise ratio for the observed data points.

A coordination theory for intelligent machines

NASA Technical Reports Server (NTRS)

Wang, Fei-Yue; Saridis, George N.

1990-01-01

A formal model for the coordination level of intelligent machines is established. The framework of the coordination level investigated consists of one dispatcher and a number of coordinators. The model called coordination structure has been used to describe analytically the information structure and information flow for the coordination activities in the coordination level. Specifically, the coordination structure offers a formalism to (1) describe the task translation of the dispatcher and coordinators; (2) represent the individual process within the dispatcher and coordinators; (3) specify the cooperation and connection among the dispatcher and coordinators; (4) perform the process analysis and evaluation; and (5) provide a control and communication mechanism for the real-time monitor or simulation of the coordination process. A simple procedure for the task scheduling in the coordination structure is presented. The task translation is achieved by a stochastic learning algorithm. The learning process is measured with entropy and its convergence is guaranteed. Finally, a case study of the coordination structure with three coordinators and one dispatcher for a simple intelligent manipulator system illustrates the proposed model and the simulation of the task processes performed on the model verifies the soundness of the theory.

Best practices in bus dispatch [summary].

DOT National Transportation Integrated Search

2012-01-01

In 2007, the National Center for Transit Research : sponsored a study of best practices in extraboard : operator management, finding that in most transit : agencies, extraboard manpower is managed by : dispatchers as one of their many functions. This...

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.

Electricity without carbon dioxide: Assessing the role of carbon capture and sequestration in United States electric markets

NASA Astrophysics Data System (ADS)

Johnson, Timothy Lawrence

2002-09-01

Stabilization of atmospheric greenhouse gas concentrations will likely require significant cuts in electric sector carbon dioxide (CO2) emissions. The ability to capture and sequester CO2 in a manner compatible with today's fossil-fuel based power generating infrastructure offers a potentially low-cost contribution to a larger climate change mitigation strategy. This thesis fills a niche between economy-wide studies of CO 2 abatement and plant-level control technology assessments by examining the contribution that carbon capture and sequestration (CCS) might make toward reducing US electric sector CO2 emissions. The assessment's thirty year perspective ensures that costs sunk in current infrastructure remain relevant and allows time for technological diffusion, but remains free of assumptions about the emergence of unidentified radical innovations. The extent to which CCS might lower CO2 mitigation costs will vary directly with the dispatch of carbon capture plants in actual power-generating systems, and will depend on both the retirement of vintage capacity and competition from abatement alternatives such as coal-to-gas fuel switching and renewable energy sources. This thesis therefore adopts a capacity planning and dispatch model to examine how the current distribution of generating units, natural gas prices, and other industry trends affect the cost of CO2 control via CCS in an actual US electric market. The analysis finds that plants with CO2 capture consistently provide significant reductions in base-load emissions at carbon prices near 100 $/tC, but do not offer an economical means of meeting peak demand unless CO2 reductions in excess of 80 percent are required. Various scenarios estimate the amount by which turn-over of the existing generating infrastructure and the severity of criteria pollutant constraints reduce mitigation costs. A look at CO2 sequestration in the seabed beneath the US Outer Continental Shelf (OCS) complements this model-driven assessment by considering issues of risk, geological storage capacity, and regulation. Extensive experience with offshore oil and gas operations suggests that the technical uncertainties associated with OCS sequestration are not large. The legality of seabed CO 2 disposal under US law and international environmental agreements, however, is ambiguous, and the OCS may be the first region where these regulatory regimes clash over CO2 sequestration.

The effectiveness of plug-in hybrid electric vehicles and renewable power in support of holistic environmental goals: Part 2 - Design and operation implications for load-balancing resources on the electric grid

NASA Astrophysics Data System (ADS)

Tarroja, Brian; Eichman, Joshua D.; Zhang, Li; Brown, Tim M.; Samuelsen, Scott

2015-03-01

A study has been performed that analyzes the effectiveness of utilizing plug-in vehicles to meet holistic environmental goals across the combined electricity and transportation sectors. In this study, plug-in hybrid electric vehicle (PHEV) penetration levels are varied from 0 to 60% and base renewable penetration levels are varied from 10 to 63%. The first part focused on the effect of installing plug-in hybrid electric vehicles on the environmental performance of the combined electricity and transportation sectors. The second part addresses impacts on the design and operation of load-balancing resources on the electric grid associated with fleet capacity factor, peaking and load-following generator capacity, efficiency, ramp rates, start-up events and the levelized cost of electricity. PHEVs using smart charging are found to counteract many of the disruptive impacts of intermittent renewable power on balancing generators for a wide range of renewable penetration levels, only becoming limited at high renewable penetration levels due to lack of flexibility and finite load size. This study highlights synergy between sustainability measures in the electric and transportation sectors and the importance of communicative dispatch of these vehicles.

An intertemporal decision framework for electrochemical energy storage management

NASA Astrophysics Data System (ADS)

He, Guannan; Chen, Qixin; Moutis, Panayiotis; Kar, Soummya; Whitacre, Jay F.

2018-05-01

Dispatchable energy storage is necessary to enable renewable-based power systems that have zero or very low carbon emissions. The inherent degradation behaviour of electrochemical energy storage (EES) is a major concern for both EES operational decisions and EES economic assessments. Here, we propose a decision framework that addresses the intertemporal trade-offs in terms of EES degradation by deriving, implementing and optimizing two metrics: the marginal benefit of usage and the average benefit of usage. These metrics are independent of the capital cost of the EES system, and, as such, separate the value of EES use from the initial cost, which provides a different perspective on storage valuation and operation. Our framework is proved to produce the optimal solution for EES life-cycle profit maximization. We show that the proposed framework offers effective ways to assess the economic values of EES, to make investment decisions for various applications and to inform related subsidy policies.

Contracts for dispatchable power

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

Kahn, E.P.; Stoft, S.; Marnay, C.

1990-10-01

Competitive bidding for electric power is maturing. Increasing numbers of utilities are soliciting proposals from private suppliers. The amount of capacity being sought is increasing, and potential suppliers appear to be abundant. Analysis of these developments still remains limited. Evidence on the behavior of this market is scarce and sketchy. The underlying economic principles that are shaping the market have not clearly been articulated. In this report we examine the economics of competitive bidding both empirically and analytically. Previous study of this market has focused on the evaluation criteria specified in Requests for Proposals (RFPs), and highly aggregated summary statisticsmore » on participation and results. We continue the examination of RFPs, but also survey the details of long term contracts that have emerged from competitive bidding. Contracts provide a new level of specific detail that has not been previously available. 68 refs., 13 figs., 25 tabs.« less

Energy management system turns data into market info

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

Traynor, P.J.; Ackerman, W.J.

1996-09-01

The designers claim that Wisconsin Power & Light Co`s new energy management system is the first system of its type in the world in terms of the comprehensiveness and scope of its stored and retrievable data. Furthermore, the system`s link to the utility`s generating assets enables powerplant management to dispatch generation resources based on up-to-date unit characteristics. That means that the new system gives WP&L a competitive tool to optimize operations as well as fine-tune its EMS based on timely load and unit response information. Additionally, the EMS gives WP&L insight into the complex issues related to the unbundling ofmore » generation resources.« less

An Energy Integrated Dispatching Strategy of Multi- energy Based on Energy Internet

NASA Astrophysics Data System (ADS)

Jin, Weixia; Han, Jun

2018-01-01

Energy internet is a new way of energy use. Energy internet achieves energy efficiency and low cost by scheduling a variety of different forms of energy. Particle Swarm Optimization (PSO) is an advanced algorithm with few parameters, high computational precision and fast convergence speed. By improving the parameters ω, c1 and c2, PSO can improve the convergence speed and calculation accuracy. The objective of optimizing model is lowest cost of fuel, which can meet the load of electricity, heat and cold after all the renewable energy is received. Due to the different energy structure and price in different regions, the optimization strategy needs to be determined according to the algorithm and model.

ISLE (Image and Signal LISP Environment): A functional language interface for signal and image processing

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

Azevedo, S.G.; Fitch, J.P.

1987-10-21

Conventional software interfaces that use imperative computer commands or menu interactions are often restrictive environments when used for researching new algorithms or analyzing processed experimental data. We found this to be true with current signal-processing software (SIG). As an alternative, ''functional language'' interfaces provide features such as command nesting for a more natural interaction with the data. The Image and Signal LISP Environment (ISLE) is an example of an interpreted functional language interface based on common LISP. Advantages of ISLE include multidimensional and multiple data-type independence through dispatching functions, dynamic loading of new functions, and connections to artificial intelligence (AI)more » software. 10 refs.« less

ISLE (Image and Signal Lisp Environment): A functional language interface for signal and image processing

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

Azevedo, S.G.; Fitch, J.P.

1987-05-01

Conventional software interfaces which utilize imperative computer commands or menu interactions are often restrictive environments when used for researching new algorithms or analyzing processed experimental data. We found this to be true with current signal processing software (SIG). Existing ''functional language'' interfaces provide features such as command nesting for a more natural interaction with the data. The Image and Signal Lisp Environment (ISLE) will be discussed as an example of an interpreted functional language interface based on Common LISP. Additional benefits include multidimensional and multiple data-type independence through dispatching functions, dynamic loading of new functions, and connections to artificial intelligencemore » software.« less

Multi-agent simulation of generation expansion in electricity markets.

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

Botterud, A; Mahalik, M. R.; Veselka, T. D.

2007-06-01

We present a new multi-agent model of generation expansion in electricity markets. The model simulates generation investment decisions of decentralized generating companies (GenCos) interacting in a complex, multidimensional environment. A probabilistic dispatch algorithm calculates prices and profits for new candidate units in different future states of the system. Uncertainties in future load, hydropower conditions, and competitors actions are represented in a scenario tree, and decision analysis is used to identify the optimal expansion decision for each individual GenCo. We test the model using real data for the Korea power system under different assumptions about market design, market concentration, and GenCo'smore » assumed expectations about their competitors investment decisions.« less

Evaluation of a Dispatcher's Route Optimization Decision Aid to Avoid Aviation Weather Hazards

NASA Technical Reports Server (NTRS)

Dorneich, Michael C.; Olofinboba, Olu; Pratt, Steve; Osborne, Dannielle; Feyereisen, Thea; Latorella, Kara

2003-01-01

This document describes the results and analysis of the formal evaluation plan for the Honeywell software tool developed under the NASA AWIN (Aviation Weather Information) 'Weather Avoidance using Route Optimization as a Decision Aid' project. The software tool aims to provide airline dispatchers with a decision aid for selecting optimal routes that avoid weather and other hazards. This evaluation compares and contrasts route selection performance with the AWIN tool to that of subjects using a more traditional dispatcher environment. The evaluation assesses gains in safety, in fuel efficiency of planned routes, and in time efficiency in the pre-flight dispatch process through the use of the AWIN decision aid. In addition, we are interested in how this AWIN tool affects constructs that can be related to performance. The construct of Situation Awareness (SA), workload, trust in an information system, and operator acceptance are assessed using established scales, where these exist, as well as through the evaluation of questionnaire responses and subject comments. The intention of the experiment is to set up a simulated operations area for the dispatchers to work in. They will be given scenarios in which they are presented with stored company routes for a particular city-pair and aircraft type. A diverse set of external weather information sources is represented by a stand-alone display (MOCK), containing the actual historical weather data typically used by dispatchers. There is also the possibility of presenting selected weather data on the route visualization tool. The company routes have not been modified to avoid the weather except in the case of one additional route generated by the Honeywell prototype flight planning system. The dispatcher will be required to choose the most appropriate and efficient flight plan route in the displayed weather conditions. The route may be modified manually or may be chosen from those automatically displayed.

Essays on measurement and evaluation of demand side management programs in the electricity industry, and impacts of firm strategy on stock price in the biotechnology industry

NASA Astrophysics Data System (ADS)

Bandres Motola, Miguel A.

Essay one estimates changes in small business customer energy consumption (kWh) patterns resulting from a seasonally differentiated pricing structure. Econometric analysis leverages cross-sectional time series data across the entire population of affected customers, from 2007 through the present. Observations include: monthly energy usage (kWh), relevant customer segmentations, local daily temperature, energy price, and region-specific economic conditions, among other variables. The study identifies the determinants of responsiveness to seasonal price differentiation. In addition, estimated energy consumption changes occurring during the 2010 summer season are reported for the average customer and in aggregate grouped by relevant customer segments, climate zone, and total customer base. Essay two develops an econometric modeling methodology to evaluate load impacts for short duration demand response events. The study analyzes time series data from a season of direct load control program tests aimed at integrating demand response into the wholesale electricity market. I have combined "fuzzy logic" with binary variables to create "fuzzy indicator variables" that allow for measurement of short duration events while using industry standard model specifications. Typically, binary variables for every hour are applied in load impact analysis of programs dispatched in hourly intervals. As programs evolve towards integration with the wholesale market, event durations become irregular and often occur for periods of only a few minutes. This methodology is innovative in that it conserves the degrees of freedom in the model while allowing for analysis of high frequency data using fixed effects. Essay three examines the effects of strategies, intangibles, and FDA news on the stocks of young biopharmaceutical firms. An event study methodology is used to explore those effects. This study investigates 20,839 announcements from 1990 to 2005. Announcements on drug development, alliances, publications, presentations, and FDA approval have a positive effect on the short-term performance of young biopharmaceutical firms. Announcements on goals not met, FDA drug approval denied, and changes in structural organizations have a negative effect on the short-term performance of young biopharmaceutical firms.

Cloud computing for energy management in smart grid - an application survey

NASA Astrophysics Data System (ADS)

Naveen, P.; Kiing Ing, Wong; Kobina Danquah, Michael; Sidhu, Amandeep S.; Abu-Siada, Ahmed

2016-03-01

The smart grid is the emerging energy system wherein the application of information technology, tools and techniques that make the grid run more efficiently. It possesses demand response capacity to help balance electrical consumption with supply. The challenges and opportunities of emerging and future smart grids can be addressed by cloud computing. To focus on these requirements, we provide an in-depth survey on different cloud computing applications for energy management in the smart grid architecture. In this survey, we present an outline of the current state of research on smart grid development. We also propose a model of cloud based economic power dispatch for smart grid.

Airline Transport Pilot, Aircraft Dispatcher, and Flight Navigator Knowledge Test Guide

DOT National Transportation Integrated Search

1995-01-01

The Flight Standards Service of the Federal Aviation Administration (FAA) has developed this guide to help applicants meet the knowledge requirements for airline transport pilot, aircraft dispatcher, and flight navigator certification. This guide con...

Aircraft Dispatcher - Practical Test Standards

DOT National Transportation Integrated Search

1995-06-01

The Flight Standards Service of the FAA has developed this practical : test book as a standard to be used by FAA inspectors and designated : examiners when conducting the aircraft dispatcher practical test. : Instructors are expected to use this book...

Design of a cooperative problem-solving system for enroute flight planning: An empirical study of its use by airline dispatchers

NASA Technical Reports Server (NTRS)

Smith, Philip J.; Mccoy, C. Elaine; Layton, Charles; Orasanu, Judith; Chappel, Sherry; Palmer, EV; Corker, Kevin

1993-01-01

In a previous report, an empirical study of 30 pilots using the Flight Planning Testbed was reported. An identical experiment using the Flight Planning Testbed (FPT), except that 27 airline dispatchers were studied, is described. Five general questions were addressed in this study: (1) under what circumstances do the introduction of computer-generated suggestions (flight plans) influence the planning behavior of dispatchers (either in a beneficial or adverse manner); (2) what is the nature of such influences (i.e., how are the person's cognitive processes changed); (3) how beneficial are the general design concepts underlying FPT (use of a graphical interface, embedding graphics in a spreadsheet, etc.); (4) how effective are the specific implementation decisions made in realizing these general design concepts; and (5) how effectively do dispatchers evaluate situations requiring replanning, and how effectively do they identify appropriate solutions to these situations.

The impacts of electricity dispatch protocols on the emission reductions due to wind power and carbon tax.

PubMed

Yu, Yang; Rajagopal, Ram

2015-02-17

Two dispatch protocols have been adopted by electricity markets to deal with the uncertainty of wind power but the effects of the selection between the dispatch protocols have not been comprehensively analyzed. We establish a framework to compare the impacts of adopting different dispatch protocols on the efficacy of using wind power and implementing a carbon tax to reduce emissions. We suggest that a market has high potential to achieve greater emission reduction by adopting the stochastic dispatch protocol instead of the static protocol when the wind energy in the market is highly uncertain or the market has enough adjustable generators, such as gas-fired combustion generators. Furthermore, the carbon-tax policy is more cost-efficient for reducing CO2 emission when the market operates according to the stochastic protocol rather than the static protocol. An empirical study, which is calibrated according to the data from the Electric Reliability Council of Texas market, confirms that using wind energy in the Texas market results in a 12% CO2 emission reduction when the market uses the stochastic dispatch protocol instead of the 8% emission reduction associated with the static protocol. In addition, if a 6$/ton carbon tax is implemented in the Texas market operated according to the stochastic protocol, the CO2 emission is similar to the emission level from the same market with a 16$/ton carbon tax operated according to the static protocol. Correspondingly, the 16$/ton carbon tax associated with the static protocol costs 42.6% more than the 6$/ton carbon tax associated with the stochastic protocol.

A Feeder-Bus Dispatch Planning Model for Emergency Evacuation in Urban Rail Transit Corridors

PubMed Central

Wang, Yun; Yan, Xuedong; Zhou, Yu; Zhang, Wenyi

2016-01-01

The mobility of modern metropolises strongly relies on urban rail transit (URT) systems, and such a heavy dependence causes that even minor service interruptions would make the URT systems unsustainable. This study aims at optimally dispatching the ground feeder-bus to coordinate with the urban rails’ operation for eliminating the effect of unexpected service interruptions in URT corridors. A feeder-bus dispatch planning model was proposed for the collaborative optimization of URT and feeder-bus cooperation under emergency situations and minimizing the total evacuation cost of the feeder-buses. To solve the model, a concept of dummy feeder-bus system is proposed to transform the non-linear model into traditional linear programming (ILP) model, i.e., traditional transportation problem. The case study of Line #2 of Nanjing URT in China was adopted to illustrate the model application and sensitivity analyses of the key variables. The modeling results show that as the evacuation time window increases, the total evacuation cost as well as the number of dispatched feeder-buses decrease, and the dispatched feeder-buses need operate for more times along the feeder-bus line. The number of dispatched feeder-buses does not show an obvious change with the increase of parking spot capacity and time window, indicating that simply increasing the parking spot capacity would cause huge waste for the emergent bus utilization. When the unbalanced evacuation demand exists between stations, the more feeder-buses are needed. The method of this study will contribute to improving transportation emergency management and resource allocation for URT systems. PMID:27676179

Development of a surveillance case definition for heat-related illness using 911 medical dispatch data.

PubMed

Bassil, Kate L; Cole, Donald C; Moineddin, Rahim; Gournis, Effie; Schwartz, Brian; Craig, Alan M; Lou, W Y Wendy; Rea, Elizabeth

2008-01-01

The adverse effects of hot weather on public health are of increasing concern. A surveillance system using 911 medical dispatch data for the detection of heat-related illness (HRI) could provide new information on the impact of excessive heat on the population. This paper describes how we identified medical dispatch call codes, called "determinants", that could represent HRI events. Approximately 500 medical dispatch determinants were reviewed in focus groups composed of Emergency Medical Services (EMS) paramedics, dispatchers, physicians, and public health epidemiologists. Each group was asked to select those determinants that might adequately represent HRI. Selections were then assessed empirically using correlations with daily mean temperature over the study period (June 1-August 31,2005). The focus groups identified 12 determinant groupings and ranked them according to specificity for HRI. Of these, "Heat/cold exposure" was deemed the most specific. The call determinant groupings with the clearest positive associations with daily mean temperature empirically were "Heat/cold exposure" (Spearman's correlation coefficient (SCC) 0.71, p < 0.0001) and "Unknown problem (man down)" (SCC 0.21, p = 0.04). Within each grouping, the determinant "Unknown status (3rd party caller)" showed significant associations, SCC = 0.34 (p = 0.001) and SCC = 0.22 (p = 0.03) respectively. Clinically-informed expertise and empirical evidence both contributed to identification of a group of 911 medical dispatch call determinants that plausibly represent HRI events. Once evaluated prospectively, these may be used in public health surveillance to better understand environmental health impacts on human populations and inform targeted public health interventions.

Alternatives to Traditional EMS Dispatch and Transport: A Scoping Review of Reported Outcomes.

PubMed

Jensen, Jan L; Carter, Alix J E; Rose, Jennifer; Visintini, Sarah; Bourdon, Emmanuelle; Brown, Ryan; McVey, Jennifer; Travers, Andrew H

2015-09-01

Emergency medical services (EMS) programs, which provide an alternative to traditional EMS dispatch or transport to the emergency department (ED), are becoming widely implemented. This scoping review identified and catalogued all outcomes used to measure such alternative EMS programs. Data Source Broad systematized bibliographic and grey literature searches were conducted. Study Selection Inclusion criteria were 911 callers/EMS patients, reported on alternatives to traditional EMS dispatch OR traditional EMS transport to the ED, and reported an outcome measure. Data Extraction The reports were categorized as either alternative to dispatch or to EMS transport, and outcome measures were categorized and described. Data Synthesis The bibliographic search retrieved 13,215 records, of which 34 articles met the inclusion criteria, with an additional 10 added from reference list hand-searching (n=44 included). In the grey literature search, 31 websites were identified, from which four met criteria and were retrieved (n=4 included). Fifteen reports (16 studies) described alternatives to EMS dispatch, and 33 reports described alternatives to EMS transport. The most common outcomes reported in the alternatives to EMS dispatch reports were service utilization and decision accuracy. Twenty-four different specific outcomes were reported. The most common outcomes reported in the alternatives to EMS transport reports were service utilization and safety, and 50 different specific outcomes were reported. Numerous outcome measures were identified in reports of alternative EMS programs, which were catalogued and described. Researchers and program leaders should achieve consensus on uniform outcome measures, to allow benchmarking and improve comparison across programs.

The linguistic and interactional factors impacting recognition and dispatch in emergency calls for out-of-hospital cardiac arrest: a mixed-method linguistic analysis study protocol

PubMed Central

Riou, Marine; Ball, Stephen; Williams, Teresa A; Whiteside, Austin; O’Halloran, Kay L; Bray, Janet; Perkins, Gavin D; Cameron, Peter; Fatovich, Daniel M; Inoue, Madoka; Bailey, Paul; Brink, Deon; Smith, Karen; Della, Phillip; Finn, Judith

2017-01-01

Introduction Emergency telephone calls placed by bystanders are crucial to the recognition of out-of-hospital cardiac arrest (OHCA), fast ambulance dispatch and initiation of early basic life support. Clear and efficient communication between caller and call-taker is essential to this time-critical emergency, yet few studies have investigated the impact that linguistic factors may have on the nature of the interaction and the resulting trajectory of the call. This research aims to provide a better understanding of communication factors impacting on the accuracy and timeliness of ambulance dispatch. Methods and analysis A dataset of OHCA calls and their corresponding metadata will be analysed from an interdisciplinary perspective, combining linguistic analysis and health services research. The calls will be transcribed and coded for linguistic and interactional variables and then used to answer a series of research questions about the recognition of OHCA and the delivery of basic life-support instructions to bystanders. Linguistic analysis of calls will provide a deeper understanding of the interactional dynamics between caller and call-taker which may affect recognition and dispatch for OHCA. Findings from this research will translate into recommendations for modifications of the protocols for ambulance dispatch and provide directions for further research. Ethics and dissemination The study has been approved by the Curtin University Human Research Ethics Committee (HR128/2013) and the St John Ambulance Western Australia Research Advisory Group. Findings will be published in peer-reviewed journals and communicated to key audiences, including ambulance dispatch professionals. PMID:28694349

Novel optimization technique of isolated microgrid with hydrogen energy storage.

PubMed

Beshr, Eman Hassan; Abdelghany, Hazem; Eteiba, Mahmoud

2018-01-01

This paper presents a novel optimization technique for energy management studies of an isolated microgrid. The system is supplied by various Distributed Energy Resources (DERs), Diesel Generator (DG), a Wind Turbine Generator (WTG), Photovoltaic (PV) arrays and supported by fuel cell/electrolyzer Hydrogen storage system for short term storage. Multi-objective optimization is used through non-dominated sorting genetic algorithm to suit the load requirements under the given constraints. A novel multi-objective flower pollination algorithm is utilized to check the results. The Pros and cons of the two optimization techniques are compared and evaluated. An isolated microgrid is modelled using MATLAB software package, dispatch of active/reactive power, optimal load flow analysis with slack bus selection are carried out to be able to minimize fuel cost and line losses under realistic constraints. The performance of the system is studied and analyzed during both summer and winter conditions and three case studies are presented for each condition. The modified IEEE 15 bus system is used to validate the proposed algorithm.

Multi-Time Step Service Restoration for Advanced Distribution Systems and Microgrids

DOE PAGES

Chen, Bo; Chen, Chen; Wang, Jianhui; ...

2017-07-07

Modern power systems are facing increased risk of disasters that can cause extended outages. The presence of remote control switches (RCSs), distributed generators (DGs), and energy storage systems (ESS) provides both challenges and opportunities for developing post-fault service restoration methodologies. Inter-temporal constraints of DGs, ESS, and loads under cold load pickup (CLPU) conditions impose extra complexity on problem formulation and solution. In this paper, a multi-time step service restoration methodology is proposed to optimally generate a sequence of control actions for controllable switches, ESSs, and dispatchable DGs to assist the system operator with decision making. The restoration sequence is determinedmore » to minimize the unserved customers by energizing the system step by step without violating operational constraints at each time step. The proposed methodology is formulated as a mixed-integer linear programming (MILP) model and can adapt to various operation conditions. Furthermore, the proposed method is validated through several case studies that are performed on modified IEEE 13-node and IEEE 123-node test feeders.« less

Novel optimization technique of isolated microgrid with hydrogen energy storage

PubMed Central

Abdelghany, Hazem; Eteiba, Mahmoud

2018-01-01

This paper presents a novel optimization technique for energy management studies of an isolated microgrid. The system is supplied by various Distributed Energy Resources (DERs), Diesel Generator (DG), a Wind Turbine Generator (WTG), Photovoltaic (PV) arrays and supported by fuel cell/electrolyzer Hydrogen storage system for short term storage. Multi-objective optimization is used through non-dominated sorting genetic algorithm to suit the load requirements under the given constraints. A novel multi-objective flower pollination algorithm is utilized to check the results. The Pros and cons of the two optimization techniques are compared and evaluated. An isolated microgrid is modelled using MATLAB software package, dispatch of active/reactive power, optimal load flow analysis with slack bus selection are carried out to be able to minimize fuel cost and line losses under realistic constraints. The performance of the system is studied and analyzed during both summer and winter conditions and three case studies are presented for each condition. The modified IEEE 15 bus system is used to validate the proposed algorithm. PMID:29466433

The prevalence of voice disorders in 911 emergency telecommunicators.

PubMed

Johns-Fiedler, Heidi; van Mersbergen, Miriam

2015-05-01

Emergency 911 dispatchers or telecommunicators have been cited as occupational voice users who could be at risk for voice disorders. To test the theoretical assumption that the 911 emergency telecommunicators (911ETCs) are exposed to risk for voice disorders because of their heavy vocal load, this study assessed the prevalence of voice complaints in 911ETCs. A cross-sectional survey was sent to two large national organizations for 911ETCs with 71 complete responses providing information about voice health, voice complaints, and work load. Although 911ETCs have a higher rate of reported voice symptoms and score higher on the Voice Handicap Index-10 than the general public, they have a voice disorder diagnosis prevalence that mirrors the prevalence of the general population. The 911ETCs may be underserved in the voice community and would benefit from education on vocal health and treatments for voice complaints. Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Multi-Time Step Service Restoration for Advanced Distribution Systems and Microgrids

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

Chen, Bo; Chen, Chen; Wang, Jianhui

Modern power systems are facing increased risk of disasters that can cause extended outages. The presence of remote control switches (RCSs), distributed generators (DGs), and energy storage systems (ESS) provides both challenges and opportunities for developing post-fault service restoration methodologies. Inter-temporal constraints of DGs, ESS, and loads under cold load pickup (CLPU) conditions impose extra complexity on problem formulation and solution. In this paper, a multi-time step service restoration methodology is proposed to optimally generate a sequence of control actions for controllable switches, ESSs, and dispatchable DGs to assist the system operator with decision making. The restoration sequence is determinedmore » to minimize the unserved customers by energizing the system step by step without violating operational constraints at each time step. The proposed methodology is formulated as a mixed-integer linear programming (MILP) model and can adapt to various operation conditions. Furthermore, the proposed method is validated through several case studies that are performed on modified IEEE 13-node and IEEE 123-node test feeders.« less

49 CFR 241.9 - Prohibition against extraterritorial dispatching; exceptions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... emergency situation, a railroad may require or permit one of its dispatchers located outside the United... or by electronic mail. (3) A list of the States that make up the FRA regions and the street and e...

Task Decomposition Model for Dispatchers in Dynamic Scheduling of Demand Responsive Transit Systems

DOT National Transportation Integrated Search

2000-06-01

Since the passage of ADA, the demand for paratransit service is steadily increasing. Paratransit companies are relying on computer automation to streamline dispatch operations, increase productivity and reduce operator stress and error. Little resear...

Impact of data link technology on railroad dispatching operations

DOT National Transportation Integrated Search

2004-10-01

This study examined data link communication as an alternative channel to voice radio for railroad dispatchers. The goal was to compare how data link affected performance compared to voice radio only communications on measures related to safety, produ...

SMART operational field test evaluation : dispatchers survey report : final report

DOT National Transportation Integrated Search

1997-06-01

The Suburban Mobility Authority for Regional Transportation (SMART) has installed an automaticscheduling and dispatch system (ASD) in Southeast Michigan in accordance with their plans toimplement ITS as a site for an operational field test. The purpo...

An analysis of the job of railroad train dispatcher.

DOT National Transportation Integrated Search

1974-04-01

This report constitutes a detailed study of the job of railroad train dispatcher, conducted to provide a data base for the derivation of criteria of job knowledge, skills and training consonant with safe operations. Documentation was reviewed; specia...

Treatment of cardiac arrest with rapid defibrillation by police in King County, Washington.

PubMed

Becker, Linda; Husain, Sofia; Kudenchuk, Peter; Doll, Ann; Rea, Tom; Eisenberg, Mickey

2014-01-01

Improving survival from out-of-hospital cardiac arrest is an ongoing challenge for emergency medical services (EMS). Various strategies for shortening the time from collapse to defibrillation have been used, and one is to equip police officers with defibrillators. Objective. We evaluated the programmatic implementation of police defibrillation to determine if such a program could improve the process of care in a high-functioning and mature EMS system. We conducted a prospective observational study of implementation of a police defibrillation in two police departments in King County, Washington, from March 1, 2010 to March 31, 2012. The program was designed to dispatch police specifically to cases with a high suspicion of cardiac arrest, defined as a patient who was unconscious and not breathing normally. We included all nontraumatic out-of-hospital cardiac arrest events that occurred prior to EMS arrival and within the city limits of the two cities. We collected both EMS and police dispatch reports to document times of call receipt, dispatch, and arrival of both agencies. We obtained rhythm recordings when the automated external defibrillators (AEDs) were used by the police. Descriptive statistics were used to measure frequency of police dispatch and to compare times to treatment between patients with a police response and those without. During the study period there were 231 cases of cardiac arrest that occurred prior to EMS arrival eligible for police response in the study communities. Police were dispatched to 124 (54%) of these cases. Of the 124, the police arrived before EMS 37 times, or 16% of the 231 cases. Police performed CPR in 29 of these cases and applied the AED in 21 of them. Of the 21 cases in which the AED was applied for cardiac arrest, a shock was delivered on first analysis for 6 patients. Although the response interval between dispatch to scene arrival was similar for EMS and police (4.5 minutes versus 4.6 minutes respectively, p = 0.08), police were dispatched considerably slower than EMS (1.8 minutes versus 0.6 minutes, p < 0.001). In the current programmatic implementation, police had a measurable but limited involvement in resuscitation. Efforts to address dispatch challenges may improve police involvement.

Solar + Storage Synergies for Managing Commercial-Customer Demand Charges

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

Gagnon, P.; Govindarajan, A.; Bird, L.

Demand charges, which are based on a customer’s maximum demand in kilowatts (kW), are a common element of electricity rate structures for commercial customers. Customer-sited solar photovoltaic (PV) systems can potentially reduce demand charges, but the level of savings is difficult to predict, given variations in demand charge designs, customer loads, and PV generation profiles. Lawrence Berkeley National Laboratory (Berkeley Lab) and the National Renewable Energy Laboratory (NREL) are collaborating on a series of studies to understand how solar PV can impact demand charges. Prior studies in the series examined demand charge reductions from solar on a stand-alone basis formore » residential and commercial customers. Those earlier analyses found that solar, alone, has limited ability to reduce demand charges depending on the specific design of the demand charge and on the shape of the customer’s load profile. This latest analysis estimates demand charge savings from solar in commercial buildings when co-deployed with behind-the-meter storage, highlighting the complementary roles of the two technologies. The analysis is based on simulated loads, solar generation, and storage dispatch across a wide variety of building types, locations, system configurations, and demand charge designs.« less

Intra-Hour Dispatch and Automatic Generator Control Demonstration with Solar Forecasting - Final Report

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

Coimbra, Carlos F. M.

2016-02-25

In this project we address multiple resource integration challenges associated with increasing levels of solar penetration that arise from the variability and uncertainty in solar irradiance. We will model the SMUD service region as its own balancing region, and develop an integrated, real-time operational tool that takes solar-load forecast uncertainties into consideration and commits optimal energy resources and reserves for intra-hour and intra-day decisions. The primary objectives of this effort are to reduce power system operation cost by committing appropriate amount of energy resources and reserves, as well as to provide operators a prediction of the generation fleet’s behavior inmore » real time for realistic PV penetration scenarios. The proposed methodology includes the following steps: clustering analysis on the expected solar variability per region for the SMUD system, Day-ahead (DA) and real-time (RT) load forecasts for the entire service areas, 1-year of intra-hour CPR forecasts for cluster centers, 1-year of smart re-forecasting CPR forecasts in real-time for determination of irreducible errors, and uncertainty quantification for integrated solar-load for both distributed and central stations (selected locations within service region) PV generation.« less

Computer-aided dispatch--traffic management center field operational test final detailed test plan : WSDOT deployment

DOT National Transportation Integrated Search

2003-10-01

The purpose of this document is to expand upon the evaluation components presented in "Computer-aided dispatch--traffic management center field operational test final evaluation plan : WSDOT deployment". This document defines the objective, approach,...

A preliminary examination of railroad dispatcher workload, stress, and fatigue

DOT National Transportation Integrated Search

2001-05-01

This report presents the methods, findings and recommendations from a field study that examined the sources and levels of railroad dispatcher workload, stress, and fatigue. The study was initiated in response to concerns raised by two Federal Railroa...

Computer-aided dispatch--traffic management center field operational test : Washington State final report

DOT National Transportation Integrated Search

2006-05-01

This document provides the final report for the evaluation of the USDOT-sponsored Computer-Aided Dispatch - Traffic Management Center Integration Field Operations Test in the State of Washington. The document discusses evaluation findings in the foll...

Analyzing railroad dispatchers' strategies : a cognitive task analysis of a distributed planning task

DOT National Transportation Integrated Search

1998-10-11

This paper describes a preliminary cognitive task analysis (CTA) that is being conducted to examine how experienced train dispatchers manage and schedule trains. The CTA uses ethnographic field observations and structured interview techniques. The ob...

A framework for analyzing the impact of data integrity/quality on electricity market operations

NASA Astrophysics Data System (ADS)

Choi, Dae Hyun

This dissertation examines the impact of data integrity/quality in the supervisory control and data acquisition (SCADA) system on real-time locational marginal price (LMP) in electricity market operations. Measurement noise and/or manipulated sensor errors in a SCADA system may mislead system operators about real-time conditions in a power system, which, in turn, may impact the price signals in real-time power markets. This dissertation serves as a first attempt to analytically investigate the impact of bad/malicious data on electric power market operations. In future power system operations, which will probably involve many more sensors, the impact of sensor data integrity/quality on grid operations will become increasingly important. The first part of this dissertation studies from a market participant's perspective a new class of malicious data attacks on state estimation, which subsequently influences the result of the newly emerging look-ahead dispatch models in the real-time power market. In comparison with prior work of cyber-attack on static dispatch where no inter-temporal ramping constraint is considered, we propose a novel attack strategy, named ramp-induced data (RID) attack, with which the attacker can manipulate the limits of ramp constraints of generators in look-ahead dispatch. It is demonstrated that the proposed attack can lead to financial profits via malicious capacity withholding of selected generators, while being undetected by the existing bad data detection algorithm embedded in today's state estimation software. In the second part, we investigate from a system operator's perspective the sensitivity of locational marginal price (LMP) with respect to data corruption-induced state estimation error in real-time power market. Two data corruption scenarios are considered, in which corrupted continuous data (e.g., the power injection/flow and voltage magnitude) falsify power flow estimate whereas corrupted discrete data (e.g., the on/off status of a circuit breaker) do network topology estimate, thus leading to the distortion of LMP. We present an analytical framework to quantify real-time LMP sensitivity subject to continuous and discrete data corruption via state estimation. The proposed framework offers system operators an analytical tool to identify economically sensitive buses and transmission lines to data corruption as well as find sensors that impact LMP changes significantly. This dissertation serves as a first step towards rigorous understanding of the fundamental coupling among cyber, physical and economical layers of operations in future smart grid.

An online dispatcher training simulator function for real-time analysis and training

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

Vadari, S.V.; Montstream, M.J.; Ross, H.B. Jr.

1995-11-01

Today`s power systems have become so complex that it is not easy for the system dispatcher to realistically predict the results of outages. The situation is compounded whenever the power grid is not in its normal configuration due to maintenance switching or equipment failure. The authors feel that the DTS is an excellent tool that can be used to teach the dispatcher how to react under these conditions. In this paper, the authors present an on-line implementation of the DTS which allows the user to initialize the DTS to an EMS disturbance using data that was captured at the timemore » of the disturbance; and place the DTS in a playback mode and go back to specific times in the scenario. The former feature allows the analyst to investigate EMS disturbances and then train the various dispatchers to be able to recognize such disturbances and to recover from them when they occur. The latter feature allows the instructor (with the trainee) to review and re-experience desired portions of the scenario. It is the authors` feeling that these two features will help the EMS operational staff understand their power system better and help their dispatchers in dealing with operational problems associated with the proper running of the system.« less

Characteristics of service requests and service processes of fire and rescue service dispatch centers: analysis of real world data and the underlying probability distributions.

PubMed

Krueger, Ute; Schimmelpfeng, Katja

2013-03-01

A sufficient staffing level in fire and rescue dispatch centers is crucial for saving lives. Therefore, it is important to estimate the expected workload properly. For this purpose, we analyzed whether a dispatch center can be considered as a call center. Current call center publications very often model call arrivals as a non-homogeneous Poisson process. This bases on the underlying assumption of the caller's independent decision to call or not to call. In case of an emergency, however, there are often calls from more than one person reporting the same incident and thus, these calls are not independent. Therefore, this paper focuses on the dependency of calls in a fire and rescue dispatch center. We analyzed and evaluated several distributions in this setting. Results are illustrated using real-world data collected from a typical German dispatch center in Cottbus ("Leitstelle Lausitz"). We identified the Pólya distribution as being superior to the Poisson distribution in describing the call arrival rate and the Weibull distribution to be more suitable than the exponential distribution for interarrival times and service times. However, the commonly used distributions offer acceptable approximations. This is important for estimating a sufficient staffing level in practice using, e.g., the Erlang-C model.

Ability of the medical priority dispatch system protocol to predict the acuity of "unknown problem" dispatch response levels.

PubMed

Clawson, Jeff; Olola, Christopher; Heward, Andy; Patterson, Brett; Scott, Greg

2008-01-01

To determine if Medical Priority Dispatch System's (MPDS's) Protocol 32-Unknown Problem interrogation-based differential dispatch coding distinguishes the acuity of patients as found at the scene by responders, when little (if any) clinical information is known. "Unknown problem" situations (i.e., all cases not fitting into any other chief complaint group) constitute 5-8% of all calls to dispatch centers. From the total patient encounters (n=599,107) in the aggregate data of one year (September 2005 to August 2006), we examined 3,947 (0.7%) encounters initially coded as "unknown problem" by the London Ambulance Service Communications Center for the scene presence of cardiac arrest (CA) and paramedic-determined high-acuity (blue-in [BI]/"lights and siren") findings. Odds ratios (ORs) with 95% confidence intervals (95% CIs) and p-values were used to assess the degree of associations between determinant codes and case outcomes (i.e., CA/BI). Statistically significant association between clinical dispatch determinant codes and case outcomes was observed in the "life status questionable" (LSQ; DELTA-1 [D-1]) and the "standing, sitting, moving, or talking" (BRAVO-1 [B-1]) code pair for the CA outcome (OR [95% CI]: 0.11 [0, 0.63], p=0.005) and for the BI outcome (OR [95% CI]: 0.47 [0.28, 0.77], p=0.003). The LSQ and all three code pairs (i.e., B-1; "community alarm notifications" [B-2]; and "unknown status" [B-3]) also demonstrated significant associations both with the CA outcome (OR [95% CI]: 0.43 [0.23, 0.81], p=0.010) and with the BI outcome (OR [95% CI]: 0.74 [0.56, 0.97], p=0.033). All the determinant code levels yielded significant association between BI and CA cases. This dispatch protocol for unknown problems successfully differentiates dispatch coding of low-acuity and non-CA patients only when specific situational information such as the patient's standing, sitting, moving, or talking can be determined during the interrogation process. Also, emergency medical dispatcher (EMD) reliance on caller-volunteered information to identify predefined critical situations does not appear to add to the protocol's ability to differentiate high-acuity and CA patients. LSQ proved to be a better predictor of both CA and BI outcomes, when compared with the BRAVO-level determinant codes within the "unknown problem" chief complaint. The B-3 (completely unknown) determinant code is a better predictor of severe outcomes than nearly all of the clinically similar BRAVO determinant codes in the entire MPDS protocol. Hence, the B-3 coding should be considered-in terms of its predictability for severe outcome-as falling somewhere between a typical DELTA and a typical BRAVO determinant code.

REopt: A Platform for Energy System Integration and Optimization: Preprint

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

Simpkins, T.; Cutler, D.; Anderson, K.

2014-08-01

REopt is NREL's energy planning platform offering concurrent, multi-technology integration and optimization capabilities to help clients meet their cost savings and energy performance goals. The REopt platform provides techno-economic decision-support analysis throughout the energy planning process, from agency-level screening and macro planning to project development to energy asset operation. REopt employs an integrated approach to optimizing a site?s energy costs by considering electricity and thermal consumption, resource availability, complex tariff structures including time-of-use, demand and sell-back rates, incentives, net-metering, and interconnection limits. Formulated as a mixed integer linear program, REopt recommends an optimally-sized mix of conventional and renewable energy, andmore » energy storage technologies; estimates the net present value associated with implementing those technologies; and provides the cost-optimal dispatch strategy for operating them at maximum economic efficiency. The REopt platform can be customized to address a variety of energy optimization scenarios including policy, microgrid, and operational energy applications. This paper presents the REopt techno-economic model along with two examples of recently completed analysis projects.« less

[Law courts and clinical documentation].

PubMed

Jiménez Carnicero, M P; Magallón, A I; Gordillo, A

2006-01-01

Background. Until 2004, requests for clinical documentation proceeding from the Judicial Administration on Specialist Care of Pamplona were received in six different centres and were processed independently, with different procedures, and documents were even sent in duplicate, with the resulting work load. This article describes the procedure for processing requests for documentation proceeding from the Law Courts and analyses the requests received. Methods. A circuit was set up to channel the judicial requests that arrived at the Specialist Health Care Centres of Pamplona and at the Juridical Regime Service of the Health System of Navarra-Osasunbidea, and a Higher Technician in Health Documentation was contracted to centralise these requests. A proceedings protocol was established to unify criteria and speed up the process, and a database was designed to register the proceedings. Results. In the course of 2004, 210 requests for documentation by legal requirement were received. Of these, 24 were claims of patrimonial responsibility and 13 were requested by lawyers with the patient's authorisation. The most frequent jurisdictional order was penal (43.33%). Ninety-three point one five percent (93.15%) of the requests proceeded from law courts in the autonomous community of Navarra. The centre that received the greatest number of requests was the "Príncipe de Viana" Consultation Centre (33.73%).The most frequently requested documentation was a copy of reports (109) and a copy of the complete clinical record (39). On two occasions the original clinical record was required. The average time of response was 6.6 days. Conclusions. The centralisation of administration has brought greater agility to the process and homogeneity in the criteria of processing. Less time is involved in preparing and dispatching the documentation, the dispatch of duplicate documents is avoided, the work load has been reduced and the dispersal of documentation is avoided, a situation that guarantees greater privacy for the patient.

Prehospital Indicators for Disaster Preparedness and Response: New York City Emergency Medical Services in Hurricane Sandy.

PubMed

Smith, Silas W; Braun, James; Portelli, Ian; Malik, Sidrah; Asaeda, Glenn; Lancet, Elizabeth; Wang, Binhuan; Hu, Ming; Lee, David C; Prezant, David J; Goldfrank, Lewis R

2016-06-01

We aimed to evaluate emergency medical services (EMS) data as disaster metrics and to assess stress in surrounding hospitals and a municipal network after the closure of Bellevue Hospital during Hurricane Sandy in 2012. We retrospectively reviewed EMS activity and call types within New York City's 911 computer-assisted dispatch database from January 1, 2011, to December 31, 2013. We evaluated EMS ambulance transports to individual hospitals during Bellevue's closure and incremental recovery from urgent care capacity, to freestanding emergency department (ED) capability, freestanding ED with 911-receiving designation, and return of inpatient services. A total of 2,877,087 patient transports were available for analysis; a total of 707,593 involved Manhattan hospitals. The 911 ambulance transports disproportionately increased at the 3 closest hospitals by 63.6%, 60.7%, and 37.2%. When Bellevue closed, transports to specific hospitals increased by 45% or more for the following call types: blunt traumatic injury, drugs and alcohol, cardiac conditions, difficulty breathing, "pedestrian struck," unconsciousness, altered mental status, and emotionally disturbed persons. EMS data identified hospitals with disproportionately increased patient loads after Hurricane Sandy. Loss of Bellevue, a public, safety net medical center, produced statistically significant increases in specific types of medical and trauma transports at surrounding hospitals. Focused redeployment of human, economic, and social capital across hospital systems may be required to expedite regional health care systems recovery. (Disaster Med Public Health Preparedness. 2016;10:333-343).

Energy management of a university campus utilizing short-term load forecasting with an artificial neural network

NASA Astrophysics Data System (ADS)

Palchak, David

Electrical load forecasting is a tool that has been utilized by distribution designers and operators as a means for resource planning and generation dispatch. The techniques employed in these predictions are proving useful in the growing market of consumer, or end-user, participation in electrical energy consumption. These predictions are based on exogenous variables, such as weather, and time variables, such as day of week and time of day as well as prior energy consumption patterns. The participation of the end-user is a cornerstone of the Smart Grid initiative presented in the Energy Independence and Security Act of 2007, and is being made possible by the emergence of enabling technologies such as advanced metering infrastructure. The optimal application of the data provided by an advanced metering infrastructure is the primary motivation for the work done in this thesis. The methodology for using this data in an energy management scheme that utilizes a short-term load forecast is presented. The objective of this research is to quantify opportunities for a range of energy management and operation cost savings of a university campus through the use of a forecasted daily electrical load profile. The proposed algorithm for short-term load forecasting is optimized for Colorado State University's main campus, and utilizes an artificial neural network that accepts weather and time variables as inputs. The performance of the predicted daily electrical load is evaluated using a number of error measurements that seek to quantify the best application of the forecast. The energy management presented utilizes historical electrical load data from the local service provider to optimize the time of day that electrical loads are being managed. Finally, the utilization of forecasts in the presented energy management scenario is evaluated based on cost and energy savings.

Computer-aided dispatch--traffic management center field operational test : state of Utah final report

DOT National Transportation Integrated Search

2006-07-01

This document provides the final report for the evaluation of the USDOT-sponsored Computer-Aided Dispatch Traffic Management Center Integration Field Operations Test in the State of Utah. The document discusses evaluation findings in the followin...

Computer-aided dispatch--traffic management center field operational test final test plans : state of Utah

DOT National Transportation Integrated Search

2004-01-01

The purpose of this document is to expand upon the evaluation components presented in "Computer-aided dispatch--traffic management center field operational test final evaluation plan : state of Utah". This document defines the objective, approach, an...

Understanding how train dispatchers manage and control trains : results of a cognitive task analysis

DOT National Transportation Integrated Search

1999-03-01

This report documents the results of a preliminary Cognitive Task Analysis (CTA) that examined how experienced train dispatchers manage and : schedule trains in today's environment The objective was to understand the cognitive demands placed on train...

49 CFR 228.17 - Dispatcher's record of train movements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Section 228.17 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HOURS OF SERVICE OF RAILROAD EMPLOYEES Records and Reporting § 228..., telephone, radio, or any other electrical or mechanical device to dispatch, report, transmit, receive, or...

Do dispatcher instructions facilitate bystander-initiated cardiopulmonary resuscitation and improve outcomes in patients with out-of-hospital cardiac arrest? A comparison of family and non-family bystanders.

PubMed

Fujie, Keiko; Nakata, Yoshio; Yasuda, Susumu; Mizutani, Taro; Hashimoto, Koichi

2014-03-01

Bystander-initiated cardiopulmonary resuscitation (CPR) has been reported to increase the possibility of survival in patients with out-of-hospital cardiopulmonary arrest (OHCA). We evaluated the effects of CPR instructions by emergency medical dispatchers on the frequency of bystander CPR and outcomes, and whether these effects differed between family and non-family bystanders. We conducted a retrospective cohort study, using Utstein-style records of OHCA taken in a rural area of Japan between January 2004 and December 2009. Of the 559 patients with non-traumatic OHCA witnessed by laypeople, 231 (41.3%) were given bystander CPR. More OHCA patients received resuscitation when the OHCA was witnessed by non-family bystanders than when it was witnessed by family members (61.4% vs. 34.2%). The patients with non-family-witnessed OHCA were more likely to be given conventional CPR (chest compression plus rescue breathing) or defibrillation with an AED than were those with family-witnessed OHCA. Dispatcher instructions significantly increased the provision of bystander CPR regardless of who the witnesses were. Neurologically favorable survival was increased by CPR in non-family-witnessed, but not in family-witnessed, OHCA patients. No difference in survival rate was observed between the cases provided with dispatcher instructions and those not provided with the instructions. Dispatcher instructions increased the frequency of bystander CPR, but did not improve the rate of neurologically favorable survival in patients with witnessed OHCA. Efforts to enhance the frequency and quality of resuscitation, especially by family members, are required for dispatcher-assisted CPR. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Limitations in Prehospital Communication Between Trauma Helicopter, Ambulance Services, and Dispatch Centers.

PubMed

Harmsen, Annelieke Maria Karien; Giannakopoulos, Georgios; Franschman, Gaby; Christiaans, Herman; Bloemers, Frank

2017-04-01

Prehospital communication with Emergency Medical Services (EMS) is carried out in hectic situations. Proper communication among all medical personal is required to enhance collaboration, to provide the best care and enable shared situational awareness. The objective of this article was to give insight into current Dutch prehospital emergency care communication among all EMS and evaluate the usage of a new physician staffed helicopter EMS (P-HEMS) cancellation model. Trauma-related P-HEMS dispatches between November 1, 2014 and May 31, 2015 for the Lifeliner 1 were included; a random sample of 100 dispatches was generated. Tape recordings on all verbal prehospital communication between the dispatch center, EMS, and P-HEMS were transcribed and analyzed. Qualitative content analysis was performed, using open coding to code key messages. Ninety-two tape recordings were analyzed. The most frequent reason for P-HEMS dispatch was suspicion of brain injury (24%). The cancellation model was followed in 66%, overruled in 9%, and not applicable in 25%. The main reason for not adhering to the model was hemodynamic stability. In 5% of P-HEMS dispatches, a complete ABCD (airway, breathing, circulation, disability) methodology was used for handover, in 9% a complete Situation-Background-Assessment-Recommendation technique, in 2% a complete Mechanism-Injuries-Signs-Treatment method was used. The other handovers were incomplete. Prehospital handover between EMS on-scene and P-HEMS often entails insufficient information. The cancellation model for P-HEMS is frequently used and promotes adequate information transfer. To increase joined decision-making, more patient and situational information needs to be handed over. Standardization of prehospital trauma handovers will facilitate this and improve trauma patient's outcome. Copyright © 2016 Elsevier Inc. All rights reserved.

Air ambulance tasking: mechanism of injury, telephone interrogation or ambulance crew assessment?

PubMed

Wilmer, Ian; Chalk, Graham; Davies, Gareth Edward; Weaver, Anne Elizabeth; Lockey, David John

2015-10-01

The identification of serious injury is critical to the tasking of air ambulances. London's Air Ambulance (LAA) is dispatched by a flight paramedic based on mechanism of injury (MOI), paramedical interrogation of caller (INT) or land ambulance crew request (REQ).This study aimed to demonstrate which of the dispatch methods was most effective (in accuracy and time) in identifying patients with serious injury. A retrospective review of 3 years of data (to December 2010) was undertaken. Appropriate dispatch was defined as the requirement for LAA to escort the patient to hospital or for resuscitation on-scene. Inaccurate dispatch was where LAA was cancelled or left the patient in the care of the land ambulance crew. The χ(2) test was used to calculate p values; with significance adjusted to account for multiple testing. There were 2203 helicopter activations analysed: MOI 18.9% (n=417), INT 62.4% (n=1375) and REQ 18.7% (n=411). Appropriate dispatch rates were MOI 58.7% (245/417), INT 69.7% (959/1375) and REQ 72.2% (297/411). INT and REQ were both significantly more accurate than MOI (p<0.0001). There was no significant difference in accuracy between INT and REQ (p=0.36). Combining MOI and INT remotely identified 80.2% of patients, with an overtriage rate of 32.8%. Mean time to dispatch (in minutes) was MOI 4, INT 8 and REQ 21. Telephone interrogation of the caller by a flight paramedic is as accurate as ground ambulance crew requests, and both are significantly better than MOI in identifying serious injury. Overtriage remains an issue with all methods. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Pre-recorded instructional audio vs. dispatchers’ conversational assistance in telephone cardiopulmonary resuscitation: A randomized controlled simulation study

PubMed Central

Birkun, Alexei; Glotov, Maksim; Ndjamen, Herman Franklin; Alaiye, Esther; Adeleke, Temidara; Samarin, Sergey

2018-01-01

BACKGROUND: To assess the effectiveness of the telephone chest-compression-only cardiopulmonary resuscitation (CPR) guided by a pre-recorded instructional audio when compared with dispatcher-assisted resuscitation. METHODS: It was a prospective, blind, randomised controlled study involving 109 medical students without previous CPR training. In a standardized mannequin scenario, after the step of dispatcher-assisted cardiac arrest recognition, the participants performed compression-only resuscitation guided over the telephone by either: (1) the pre-recorded instructional audio (n=57); or (2) verbal dispatcher assistance (n=52). The simulation video records were reviewed to assess the CPR performance using a 13-item checklist. The interval from call reception to the first compression, total number and rate of compressions, total number and duration of pauses after the first compression were also recorded. RESULTS: There were no significant differences between the recording-assisted and dispatcher-assisted groups based on the overall performance score (5.6±2.2 vs. 5.1±1.9, P>0.05) or individual criteria of the CPR performance checklist. The recording-assisted group demonstrated significantly shorter time interval from call receipt to the first compression (86.0±14.3 vs. 91.2±14.2 s, P<0.05), higher compression rate (94.9±26.4 vs. 89.1±32.8 min-1) and number of compressions provided (170.2±48.0 vs. 156.2±60.7). CONCLUSION: When provided by untrained persons in the simulated settings, the compression-only resuscitation guided by the pre-recorded instructional audio is no less efficient than dispatcher-assisted CPR. Future studies are warranted to further assess feasibility of using instructional audio aid as a potential alternative to dispatcher assistance.

Mobile-phone dispatch of laypersons for CPR in out-of-hospital cardiac arrest.

PubMed

Ringh, Mattias; Rosenqvist, Mårten; Hollenberg, Jacob; Jonsson, Martin; Fredman, David; Nordberg, Per; Järnbert-Pettersson, Hans; Hasselqvist-Ax, Ingela; Riva, Gabriel; Svensson, Leif

2015-06-11

Cardiopulmonary resuscitation (CPR) performed by bystanders is associated with increased survival rates among persons with out-of-hospital cardiac arrest. We investigated whether rates of bystander-initiated CPR could be increased with the use of a mobile-phone positioning system that could instantly locate mobile-phone users and dispatch lay volunteers who were trained in CPR to a patient nearby with out-of-hospital cardiac arrest. We conducted a blinded, randomized, controlled trial in Stockholm from April 2012 through December 2013. A mobile-phone positioning system that was activated when ambulance, fire, and police services were dispatched was used to locate trained volunteers who were within 500 m of patients with out-of-hospital cardiac arrest; volunteers were then dispatched to the patients (the intervention group) or not dispatched to them (the control group). The primary outcome was bystander-initiated CPR before the arrival of ambulance, fire, and police services. A total of 5989 lay volunteers who were trained in CPR were recruited initially, and overall 9828 were recruited during the study. The mobile-phone positioning system was activated in 667 out-of-hospital cardiac arrests: 46% (306 patients) in the intervention group and 54% (361 patients) in the control group. The rate of bystander-initiated CPR was 62% (188 of 305 patients) in the intervention group and 48% (172 of 360 patients) in the control group (absolute difference for intervention vs. control, 14 percentage points; 95% confidence interval, 6 to 21; P<0.001). A mobile-phone positioning system to dispatch lay volunteers who were trained in CPR was associated with significantly increased rates of bystander-initiated CPR among persons with out-of-hospital cardiac arrest. (Funded by the Swedish Heart-Lung Foundation and Stockholm County; ClinicalTrials.gov number, NCT01789554.).

The linguistic and interactional factors impacting recognition and dispatch in emergency calls for out-of-hospital cardiac arrest: a mixed-method linguistic analysis study protocol.

PubMed

Riou, Marine; Ball, Stephen; Williams, Teresa A; Whiteside, Austin; O'Halloran, Kay L; Bray, Janet; Perkins, Gavin D; Cameron, Peter; Fatovich, Daniel M; Inoue, Madoka; Bailey, Paul; Brink, Deon; Smith, Karen; Della, Phillip; Finn, Judith

2017-07-09

Emergency telephone calls placed by bystanders are crucial to the recognition of out-of-hospital cardiac arrest (OHCA), fast ambulance dispatch and initiation of early basic life support. Clear and efficient communication between caller and call-taker is essential to this time-critical emergency, yet few studies have investigated the impact that linguistic factors may have on the nature of the interaction and the resulting trajectory of the call. This research aims to provide a better understanding of communication factors impacting on the accuracy and timeliness of ambulance dispatch. A dataset of OHCA calls and their corresponding metadata will be analysed from an interdisciplinary perspective, combining linguistic analysis and health services research. The calls will be transcribed and coded for linguistic and interactional variables and then used to answer a series of research questions about the recognition of OHCA and the delivery of basic life-support instructions to bystanders. Linguistic analysis of calls will provide a deeper understanding of the interactional dynamics between caller and call-taker which may affect recognition and dispatch for OHCA. Findings from this research will translate into recommendations for modifications of the protocols for ambulance dispatch and provide directions for further research. The study has been approved by the Curtin University Human Research Ethics Committee (HR128/2013) and the St John Ambulance Western Australia Research Advisory Group. Findings will be published in peer-reviewed journals and communicated to key audiences, including ambulance dispatch professionals. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Unraveling the Importance of Climate Change Resilience in Planning the Future Sustainable Energy System

NASA Astrophysics Data System (ADS)

Tarroja, B.; AghaKouchak, A.; Forrest, K.; Chiang, F.; Samuelsen, S.

2017-12-01

In response to concerns regarding the environmental impacts of the current energy resource mix, significant research efforts have been focused on determining the future energy resource mix to meet emissions reduction and environmental sustainability goals. Many of these studies focus on various constraints such as costs, grid operability requirements, and environmental performance, and develop different plans for the rollout of energy resources between the present and future years. One aspect that has not yet been systematically taken into account in these planning studies, however, is the potential impacts that changing climates may have on the availability and performance of key energy resources that compose these plans. This presentation will focus on a case study for California which analyzes the impacts of climate change on the greenhouse gas emissions and renewable resource utilization of an energy resource plan developed by Energy Environmental Economics for meeting the state's year 2050 greenhouse gas goal of 80% reduction in emissions by the year 2050. Specifically, climate change impacts on three aspects of the energy system are investigated: 1) changes in hydropower generation due to altered precipitation, streamflow and runoff patterns, 2) changes in the availability of solar thermal and geothermal power plant capacity due to shifting water availability, and 3) changes in the residential and commercial electric building loads due to increased temperatures. These impacts were discovered to cause the proposed resource plan to deviate from meeting its emissions target by up to 5.9 MMT CO2e/yr and exhibit a reduction in renewable resource penetration of up to 3.1% of total electric energy. The impacts of climate change on energy system performance were found to be mitigated by increasing the flexibility of the energy system through increased storage and electric load dispatchability. Overall, this study highlights the importance of taking into account and building resilience against potential climate change impacts on the energy system in planning the future energy resource mix.

14 CFR Special Federal Aviation... - Alternative Communications and Dispatching Procedures

Code of Federal Regulations, 2010 CFR

2010-01-01

... Procedures Federal Special Federal Aviation Regulation 80 Aeronautics and Space FEDERAL AVIATION... No. 80 Special Federal Aviation Regulation 80—Alternative Communications and Dispatching Procedures 1. Applicability. This Special Federal Aviation Regulation applies to each holder of an air carrier or operating...

14 CFR Special Federal Aviation... - Alternative Communications and Dispatching Procedures

Code of Federal Regulations, 2011 CFR

2011-01-01

... Procedures Federal Special Federal Aviation Regulation 80 Aeronautics and Space FEDERAL AVIATION... No. 80 Special Federal Aviation Regulation 80—Alternative Communications and Dispatching Procedures 1. Applicability. This Special Federal Aviation Regulation applies to each holder of an air carrier or operating...

77 FR 64498 - Combined Notice of Filings #1

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-22

... Dispatchable Wind 1, LLC. Description: TEXAS DISPATCHABLE WIND 1, LLC MBR Application to be effective 10/10... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 1 Take notice.../12. Docket Numbers: ER12-2619-001. Applicants: Eligo Energy, LLC. Description: Amendment to...

Emergency Medical Dispatch. National Standard Curriculum. Instructor Guide. Trainee Guide.

ERIC Educational Resources Information Center

National Highway Traffic Safety Administration (DOT), Washington, DC.

This guide contains all instructor materials and requirements for the National Highway Traffic Safety Administration (NHTSA), Emergency Medical Dispatch (EMD) National Standard Curriculum. It includes lesson plans, instructional aids, and tools and supporting information designed to elevate trained and experienced public safety telecommunicators…

Evaluation of transit operations : data applications of Tri-Met's automated bus dispatching system

DOT National Transportation Integrated Search

2001-02-01

This paper presents an analysis of operating performance for Tri-Met, the transit provider for the Portland, Oregon metropolitan area. The analysis draws on data recovered by Tri-Met's automated Bus Dispatching System (BDS) and focuses on two main su...

Highballing with flimsies : working under train orders on the Espee's coast line

DOT National Transportation Integrated Search

1990-01-01

In classic timetable and train-order territory, the study focuses on several dimensions of train : dispatchers' work, viewed through the other end of the telescope, i.e., from the perspective of the : dispatched train crewmembers and others in the fi...

Dispatching demand response transit service maximizing productivity and service quality guidebook : final report, March 2009.

DOT National Transportation Integrated Search

2009-03-01

The ability of transit agencies to staff dispatch effectively and use technology to its full advantage is critical : in responding proactively as service changes occur and in making sound routing decisions. Sound routing : decisions result in improve...

14 CFR 121.535 - Responsibility for operational control: Flag operations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight in... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations...— (1) Monitoring the progress of each flight; (2) Issuing necessary instructions and information for...

14 CFR 121.535 - Responsibility for operational control: Flag operations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight in... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations...— (1) Monitoring the progress of each flight; (2) Issuing necessary instructions and information for...

14 CFR 121.535 - Responsibility for operational control: Flag operations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight in... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations...— (1) Monitoring the progress of each flight; (2) Issuing necessary instructions and information for...

14 CFR 121.535 - Responsibility for operational control: Flag operations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight in... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations...— (1) Monitoring the progress of each flight; (2) Issuing necessary instructions and information for...

14 CFR 121.535 - Responsibility for operational control: Flag operations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight in... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations...— (1) Monitoring the progress of each flight; (2) Issuing necessary instructions and information for...

Reliability evaluation of microgrid considering incentive-based demand response

NASA Astrophysics Data System (ADS)

Huang, Ting-Cheng; Zhang, Yong-Jun

2017-07-01

Incentive-based demand response (IBDR) can guide customers to adjust their behaviour of electricity and curtail load actively. Meanwhile, distributed generation (DG) and energy storage system (ESS) can provide time for the implementation of IBDR. The paper focus on the reliability evaluation of microgrid considering IBDR. Firstly, the mechanism of IBDR and its impact on power supply reliability are analysed. Secondly, the IBDR dispatch model considering customer’s comprehensive assessment and the customer response model are developed. Thirdly, the reliability evaluation method considering IBDR based on Monte Carlo simulation is proposed. Finally, the validity of the above models and method is studied through numerical tests on modified RBTS Bus6 test system. Simulation results demonstrated that IBDR can improve the reliability of microgrid.

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

Pennock, Kenneth; Makarov, Yuri V.; Rajagopal, Sankaran

The need for proactive closed-loop integration of uncertainty information into system operations and probability-based controls is widely recognized, but rarely implemented in system operations. Proactive integration for this project means that the information concerning expected uncertainty ranges for net load and balancing requirements, including required balancing capacity, ramping and ramp duration characteristics, will be fed back into the generation commitment and dispatch algorithms to modify their performance so that potential shortages of these characteristics can be prevented. This basic, yet important, premise is the motivating factor for this project. The achieved project goal is to demonstrate the benefit of suchmore » a system. The project quantifies future uncertainties, predicts additional system balancing needs including the prediction intervals for capacity and ramping requirements of future dispatch intervals, evaluates the impacts of uncertainties on transmission including the risk of overloads and voltage problems, and explores opportunities for intra-hour generation adjustments helping to provide more flexibility for system operators. The resulting benefits culminate in more reliable grid operation in the face of increased system uncertainty and variability caused by solar power. The project identifies that solar power does not require special separate penetration level restrictions or penalization for its intermittency. Ultimately, the collective consideration of all sources of intermittency distributed over a wide area unified with the comprehensive evaluation of various elements of balancing process, i.e. capacity, ramping, and energy requirements, help system operators more robustly and effectively balance generation against load and interchange. This project showed that doing so can facilitate more solar and other renewable resources on the grid without compromising reliability and control performance. Efforts during the project included developing and integrating advanced probabilistic solar forecasts, including distributed PV forecasts, into closed –loop decision making processes. Additionally, new uncertainty quantifications methods and tools for the direct integration of uncertainty and variability information into grid operations at the transmission and distribution levels were developed and tested. During Phase 1, project work focused heavily on the design, development and demonstration of a set of processes and tools that could reliably and efficiently incorporate solar power into California’s grid operations. In Phase 2, connectivity between the ramping analysis tools and market applications software were completed, multiple dispatch scenarios demonstrated a successful reduction of overall uncertainty and an analysis to quantify increases in system operator reliability, and the transmission and distribution system uncertainty prediction tool was introduced to system operation engineers in a live webinar. The project met its goals, the experiments prove the advancements to methods and tools, when working together, are beneficial to not only the California Independent System Operator, but the benefits are transferable to other system operators in the United States.« less

A biometeorology study of climate and heat-related morbidity in Phoenix from 2001 to 2006

NASA Astrophysics Data System (ADS)

Golden, Jay S.; Hartz, Donna; Brazel, Anthony; Luber, George; Phelan, Patrick

2008-07-01

Heat waves kill more people in the United States than hurricanes, tornadoes, earthquakes, and floods combined. Recently, international attention focused on the linkages and impacts of human health vulnerability to urban climate when Western Europe experienced over 30,000 excess deaths during the heat waves of the summer of 2003—surpassing the 1995 heat wave in Chicago, Illinois, that killed 739. While Europe dealt with heat waves, in the United States, Phoenix, Arizona, established a new all-time high minimum temperature for the region on July 15, 2003. The low temperature of 35.5°C (96°F) was recorded, breaking the previous all-time high minimum temperature record of 33.8°C (93°F). While an extensive literature on heat-related mortality exists, greater understanding of influences of heat-related morbidity is required due to climate change and rapid urbanization influences. We undertook an analysis of 6 years (2001 2006) of heat-related dispatches through the Phoenix Fire Department regional dispatch center to examine temporal, climatic and other non-spatial influences contributing to high-heat-related medical dispatch events. The findings identified that there were no significant variations in day-of-week dispatch events. The greatest incidence of heat-related medical dispatches occurred between the times of peak solar irradiance and maximum diurnal temperature, and during times of elevated human comfort indices (combined temperature and relative humidity).

Outcome of patients identified as dead (beyond resuscitation) at the point of the emergency call.

PubMed

Harvey, L; Woollard, M

2004-05-01

Currently, an emergency ambulance is dispatched to all cardiac arrest victims. This study aimed to determine the outcome of patients with a dispatch code of 09B01 ("obvious death") and considers the appropriateness of dispatching a non-emergency response. Dispatch records, patient report forms, and hospital records were reviewed to determine patient outcome. Within the one year study period 141 emergency calls were coded as 09B01. Records were obtained for 59 of these cases (42%). Ambulance crews diagnosed 54 as beyond resuscitation (91.5%, 95% CI 79.5% to 96.2%). Three received resuscitation attempts (5.1%, 95% CI 1.1% to 14.2%): two were subsequently pronounced dead at scene and one on arrival at hospital. Two patients were not in cardiac arrest (3.4%, 95% CI 0.4% to 11.7%): one was a transiently unconscious assault victim, and one had a hand injury after a road accident. Three patients coded as 09B01 were transported to hospital for treatment other than confirmation of death (5.1%, 95% CI 1.1% to 14.2%). Not all patients coded 09B01 by dispatchers are assessed as "dead beyond resuscitation" by attending ambulance crews. Although poor data recovery and a small sample size limited the study, its findings suggest that it is inappropriate to allocate a non-emergency response to 09B01 (obvious death) calls.

Home Care Providers to the Rescue: A Novel First-Responder Programme

PubMed Central

Hansen, Steen M.; Brøndum, Stig; Thomas, Grethe; Rasmussen, Susanne R.; Kvist, Birgitte; Christensen, Anette; Lyng, Charlotte; Lindberg, Jan; Lauritsen, Torsten L. B.; Lippert, Freddy K.; Torp-Pedersen, Christian; Hansen, Poul A.

2015-01-01

Aim To describe the implementation of a novel first-responder programme in which home care providers equipped with automated external defibrillators (AEDs) were dispatched in parallel with existing emergency medical services in the event of a suspected out-of-hospital cardiac arrest (OHCA). Methods We evaluated a one-year prospective study that trained home care providers in performing cardiopulmonary resuscitation (CPR) and using an AED in cases of suspected OHCA. Data were collected from cardiac arrest case files, case files from each provider dispatch and a survey among dispatched providers. The study was conducted in a rural district in Denmark. Results Home care providers were dispatched to 28 of the 60 OHCAs that occurred in the study period. In ten cases the providers arrived before the ambulance service and subsequently performed CPR. AED analysis was executed in three cases and shock was delivered in one case. For 26 of the 28 cases, the cardiac arrest occurred in a private home. Ninety-five per cent of the providers who had been dispatched to a cardiac arrest reported feeling prepared for managing the initial resuscitation, including use of AED. Conclusion Home care providers are suited to act as first-responders in predominantly rural and residential districts. Future follow-up will allow further evaluation of home care provider arrivals and patient survival. PMID:26509532

A biometeorology study of climate and heat-related morbidity in Phoenix from 2001 to 2006.

PubMed

Golden, Jay S; Hartz, Donna; Brazel, Anthony; Luber, George; Phelan, Patrick

2008-07-01

Heat waves kill more people in the United States than hurricanes, tornadoes, earthquakes, and floods combined. Recently, international attention focused on the linkages and impacts of human health vulnerability to urban climate when Western Europe experienced over 30,000 excess deaths during the heat waves of the summer of 2003-surpassing the 1995 heat wave in Chicago, Illinois, that killed 739. While Europe dealt with heat waves, in the United States, Phoenix, Arizona, established a new all-time high minimum temperature for the region on July 15, 2003. The low temperature of 35.5 degrees C (96 degrees F) was recorded, breaking the previous all-time high minimum temperature record of 33.8 degrees C (93 degrees F). While an extensive literature on heat-related mortality exists, greater understanding of influences of heat-related morbidity is required due to climate change and rapid urbanization influences. We undertook an analysis of 6 years (2001-2006) of heat-related dispatches through the Phoenix Fire Department regional dispatch center to examine temporal, climatic and other non-spatial influences contributing to high-heat-related medical dispatch events. The findings identified that there were no significant variations in day-of-week dispatch events. The greatest incidence of heat-related medical dispatches occurred between the times of peak solar irradiance and maximum diurnal temperature, and during times of elevated human comfort indices (combined temperature and relative humidity).

Constructing probabilistic scenarios for wide-area solar power generation

DOE PAGES

Woodruff, David L.; Deride, Julio; Staid, Andrea; ...

2017-12-22

Optimizing thermal generation commitments and dispatch in the presence of high penetrations of renewable resources such as solar energy requires a characterization of their stochastic properties. In this study, we describe novel methods designed to create day-ahead, wide-area probabilistic solar power scenarios based only on historical forecasts and associated observations of solar power production. Each scenario represents a possible trajectory for solar power in next-day operations with an associated probability computed by algorithms that use historical forecast errors. Scenarios are created by segmentation of historic data, fitting non-parametric error distributions using epi-splines, and then computing specific quantiles from these distributions.more » Additionally, we address the challenge of establishing an upper bound on solar power output. Our specific application driver is for use in stochastic variants of core power systems operations optimization problems, e.g., unit commitment and economic dispatch. These problems require as input a range of possible future realizations of renewables production. However, the utility of such probabilistic scenarios extends to other contexts, e.g., operator and trader situational awareness. Finally, we compare the performance of our approach to a recently proposed method based on quantile regression, and demonstrate that our method performs comparably to this approach in terms of two widely used methods for assessing the quality of probabilistic scenarios: the Energy score and the Variogram score.« less

Constructing probabilistic scenarios for wide-area solar power generation

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

Woodruff, David L.; Deride, Julio; Staid, Andrea

Optimizing thermal generation commitments and dispatch in the presence of high penetrations of renewable resources such as solar energy requires a characterization of their stochastic properties. In this study, we describe novel methods designed to create day-ahead, wide-area probabilistic solar power scenarios based only on historical forecasts and associated observations of solar power production. Each scenario represents a possible trajectory for solar power in next-day operations with an associated probability computed by algorithms that use historical forecast errors. Scenarios are created by segmentation of historic data, fitting non-parametric error distributions using epi-splines, and then computing specific quantiles from these distributions.more » Additionally, we address the challenge of establishing an upper bound on solar power output. Our specific application driver is for use in stochastic variants of core power systems operations optimization problems, e.g., unit commitment and economic dispatch. These problems require as input a range of possible future realizations of renewables production. However, the utility of such probabilistic scenarios extends to other contexts, e.g., operator and trader situational awareness. Finally, we compare the performance of our approach to a recently proposed method based on quantile regression, and demonstrate that our method performs comparably to this approach in terms of two widely used methods for assessing the quality of probabilistic scenarios: the Energy score and the Variogram score.« less

Training Program for Emergency Medical Technician: Dispatcher. 2--Instructor Lesson Plans.

ERIC Educational Resources Information Center

National Highway Traffic Safety Administration (DOT), Washington, DC.

Intended to assist instructors who wish to conduct a training course for emergency medical technicians (EMTs) serving as dispatchers, this document contains detailed lesson plans organized to structure course presentations. Each lesson plan includes the following elements: unit objectives; suggestions for adapting the lessons to local policies and…

40 CFR 72.92 - Phase I unit allowance surrender.

Code of Federal Regulations, 2010 CFR

2010-07-01

... chapter) for all Phase I units in the dispatch system. (iii) Calculating percentage change in dispatch... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Phase I unit allowance surrender. 72... (CONTINUED) PERMITS REGULATION Compliance Certification § 72.92 Phase I unit allowance surrender. (a) Annual...

40 CFR 72.92 - Phase I unit allowance surrender.

Code of Federal Regulations, 2011 CFR

2011-07-01

... chapter) for all Phase I units in the dispatch system. (iii) Calculating percentage change in dispatch... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Phase I unit allowance surrender. 72... (CONTINUED) PERMITS REGULATION Compliance Certification § 72.92 Phase I unit allowance surrender. (a) Annual...

45 CFR 2105.3 - Action on initial requests.

Code of Federal Regulations, 2010 CFR

2010-10-01

... sound grounds. (b) Determination will be dispatched within ten days, excluding Saturdays, Sundays, and... initial determination on requests may be delayed up to a total of ten additional days, excluding Saturdays, Sundays, and legal public holidays and notice of such delay shall be dispatched within the first ten days...

77 FR 64500 - Combined Notice of Filings #1

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-22

...-000. Applicants: Texas Dispatchable Wind 1, LLC. Description: Self-Certification of Texas Dispatchable Wind 1, LLC. Filed Date: 10/11/12. Accession Number: 20121011-5210. Comments Due: 5 p.m. ET 11/1/12... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 1 Take notice...

49 CFR 241.11 - Prohibition against conducting a railroad operation dispatched by an extraterritorial dispatcher...

Code of Federal Regulations, 2010 CFR

2010-10-01

... opportunity to file a waiver request pursuant to § 241.7. (c) Emergencies. (1) In an emergency situation, a... mail. (3) A list of the States that make up the FRA regions and the street and e-mail addresses and fax...

14 CFR 121.605 - Airplane equipment.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Airplane equipment. 121.605 Section 121.605..., FLAG, AND SUPPLEMENTAL OPERATIONS Dispatching and Flight Release Rules § 121.605 Airplane equipment. No person may dispatch or release an airplane unless it is airworthy and is equipped as prescribed in § 121...

14 CFR 121.605 - Airplane equipment.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Airplane equipment. 121.605 Section 121.605..., FLAG, AND SUPPLEMENTAL OPERATIONS Dispatching and Flight Release Rules § 121.605 Airplane equipment. No person may dispatch or release an airplane unless it is airworthy and is equipped as prescribed in § 121...

14 CFR 121.605 - Airplane equipment.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Airplane equipment. 121.605 Section 121.605..., FLAG, AND SUPPLEMENTAL OPERATIONS Dispatching and Flight Release Rules § 121.605 Airplane equipment. No person may dispatch or release an airplane unless it is airworthy and is equipped as prescribed in § 121...

14 CFR 121.605 - Airplane equipment.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Airplane equipment. 121.605 Section 121.605..., FLAG, AND SUPPLEMENTAL OPERATIONS Dispatching and Flight Release Rules § 121.605 Airplane equipment. No person may dispatch or release an airplane unless it is airworthy and is equipped as prescribed in § 121...

14 CFR 121.605 - Airplane equipment.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airplane equipment. 121.605 Section 121.605..., FLAG, AND SUPPLEMENTAL OPERATIONS Dispatching and Flight Release Rules § 121.605 Airplane equipment. No person may dispatch or release an airplane unless it is airworthy and is equipped as prescribed in § 121...

78 FR 63172 - Commission Information Collection Activities (FERC-733); Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-23

... Electric Reliability Corporation (NERC) and EIA, to fielding and collecting data using a FERC designed... Commission in time to complete the 2014 report to Congress. NERC, as the Electric Reliability Organization... dispatchable and non-dispatchable resources that it needs to conduct its reliability work. Reporting demand...

MIT - Massachusetts Institute of Technology

Science.gov Websites

energy cancer diversity global industry public service Solve The MIT Campaign for a Better World give to produce electricity Drug-carrying nanoparticles could help fight brain cancer Drug-carrying nanoparticles could help fight brain cancer New dispatching approach optimizes a city's taxi fleet New dispatching

14 CFR 121.611 - Dispatch or flight release under VFR.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Dispatch or flight release under VFR. 121.611 Section 121.611 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... operation unless the ceiling and visibility en route, as indicated by available weather reports or forecasts...

14 CFR 121.611 - Dispatch or flight release under VFR.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Dispatch or flight release under VFR. 121.611 Section 121.611 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... operation unless the ceiling and visibility en route, as indicated by available weather reports or forecasts...

14 CFR 121.611 - Dispatch or flight release under VFR.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Dispatch or flight release under VFR. 121.611 Section 121.611 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... operation unless the ceiling and visibility en route, as indicated by available weather reports or forecasts...

14 CFR 121.611 - Dispatch or flight release under VFR.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Dispatch or flight release under VFR. 121.611 Section 121.611 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... operation unless the ceiling and visibility en route, as indicated by available weather reports or forecasts...

14 CFR 121.611 - Dispatch or flight release under VFR.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Dispatch or flight release under VFR. 121.611 Section 121.611 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... operation unless the ceiling and visibility en route, as indicated by available weather reports or forecasts...

14 CFR 121.99 - Communications facilities-domestic and flag operations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... communication approved by the FAA certificate holding district office, is available over the entire route. The... communications under normal operating conditions between each airplane and the appropriate dispatch office, and... dispatch office must be independent of any system operated by the United States. (c) Each certificate...

14 CFR 121.99 - Communications facilities-domestic and flag operations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... communication approved by the FAA certificate holding district office, is available over the entire route. The... communications under normal operating conditions between each airplane and the appropriate dispatch office, and... dispatch office must be independent of any system operated by the United States. (c) Each certificate...

Wind Energy Forecasting: A Collaboration of the National Center for Atmospheric Research (NCAR) and Xcel Energy

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

Parks, K.; Wan, Y. H.; Wiener, G.

2011-10-01

The focus of this report is the wind forecasting system developed during this contract period with results of performance through the end of 2010. The report is intentionally high-level, with technical details disseminated at various conferences and academic papers. At the end of 2010, Xcel Energy managed the output of 3372 megawatts of installed wind energy. The wind plants span three operating companies1, serving customers in eight states2, and three market structures3. The great majority of the wind energy is contracted through power purchase agreements (PPAs). The remainder is utility owned, Qualifying Facilities (QF), distributed resources (i.e., 'behind the meter'),more » or merchant entities within Xcel Energy's Balancing Authority footprints. Regardless of the contractual or ownership arrangements, the output of the wind energy is balanced by Xcel Energy's generation resources that include fossil, nuclear, and hydro based facilities that are owned or contracted via PPAs. These facilities are committed and dispatched or bid into day-ahead and real-time markets by Xcel Energy's Commercial Operations department. Wind energy complicates the short and long-term planning goals of least-cost, reliable operations. Due to the uncertainty of wind energy production, inherent suboptimal commitment and dispatch associated with imperfect wind forecasts drives up costs. For example, a gas combined cycle unit may be turned on, or committed, in anticipation of low winds. The reality is winds stayed high, forcing this unit and others to run, or be dispatched, to sub-optimal loading positions. In addition, commitment decisions are frequently irreversible due to minimum up and down time constraints. That is, a dispatcher lives with inefficient decisions made in prior periods. In general, uncertainty contributes to conservative operations - committing more units and keeping them on longer than may have been necessary for purposes of maintaining reliability. The downside is costs are higher. In organized electricity markets, units that are committed for reliability reasons are paid their offer price even when prevailing market prices are lower. Often, these uplift charges are allocated to market participants that caused the inefficient dispatch in the first place. Thus, wind energy facilities are burdened with their share of costs proportional to their forecast errors. For Xcel Energy, wind energy uncertainty costs manifest depending on specific market structures. In the Public Service of Colorado (PSCo), inefficient commitment and dispatch caused by wind uncertainty increases fuel costs. Wind resources participating in the Midwest Independent System Operator (MISO) footprint make substantial payments in the real-time markets to true-up their day-ahead positions and are additionally burdened with deviation charges called a Revenue Sufficiency Guarantee (RSG) to cover out of market costs associated with operations. Southwest Public Service (SPS) wind plants cause both commitment inefficiencies and are charged Southwest Power Pool (SPP) imbalance payments due to wind uncertainty and variability. Wind energy forecasting helps mitigate these costs. Wind integration studies for the PSCo and Northern States Power (NSP) operating companies have projected increasing costs as more wind is installed on the system due to forecast error. It follows that reducing forecast error would reduce these costs. This is echoed by large scale studies in neighboring regions and states that have recommended adoption of state-of-the-art wind forecasting tools in day-ahead and real-time planning and operations. Further, Xcel Energy concluded reduction of the normalized mean absolute error by one percent would have reduced costs in 2008 by over $1 million annually in PSCo alone. The value of reducing forecast error prompted Xcel Energy to make substantial investments in wind energy forecasting research and development.« less

Microgrid to enable optimal distributed energy retail and end-user demand response

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

Jin, Ming; Feng, Wei; Marnay, Chris

In the face of unprecedented challenges in environmental sustainability and grid resilience, there is an increasingly held consensus regarding the adoption of distributed and renewable energy resources such as microgrids (MGs), and the utilization of flexible electric loads by demand response (DR) to potentially drive a necessary paradigm shift in energy production and consumption patterns. However, the potential value of distributed generation and demand flexibility has not yet been fully realized in the operation of MGs. This study investigates the pricing and operation strategy with DR for a MG retailer in an integrated energy system (IES). Based on co-optimizing retailmore » rates and MG dispatch formulated as a mixed integer quadratic programming (MIQP) problem, our model devises a dynamic pricing scheme that reflects the cost of generation and promotes DR, in tandem with an optimal dispatch plan that exploits spark spread and facilitates the integration of renewables, resulting in improved retailer profits and system stability. Main issues like integrated energy coupling and customer bill reduction are addressed during pricing to ensure rates competitiveness and customer protection. By evaluating on real datasets, the system is demonstrated to optimally coordinate storage, renewables, and combined heat and power (CHP), reduce carbon dioxide emission while maintaining profits, and effectively alleviate the PV curtailment problem. Finally, the model can be used by retailers and MG operators to optimize their operations, as well as regulators to design new utility rates in support of the ongoing transformation of energy systems.« less

Development of Nuclear Renewable Oil Shale Systems for Flexible Electricity and Reduced Fossil Fuel Emissions

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

Daniel Curtis; Charles Forsberg; Humberto Garcia

2015-05-01

We propose the development of Nuclear Renewable Oil Shale Systems (NROSS) in northern Europe, China, and the western United States to provide large supplies of flexible, dispatchable, very-low-carbon electricity and fossil fuel production with reduced CO2 emissions. NROSS are a class of large hybrid energy systems in which base-load nuclear reactors provide the primary energy used to produce shale oil from kerogen deposits and simultaneously provide flexible, dispatchable, very-low-carbon electricity to the grid. Kerogen is solid organic matter trapped in sedimentary shale, and large reserves of this resource, called oil shale, are found in northern Europe, China, and the westernmore » United States. NROSS couples electricity generation and transportation fuel production in a single operation, reduces lifecycle carbon emissions from the fuel produced, improves revenue for the nuclear plant, and enables a major shift toward a very-low-carbon electricity grid. NROSS will require a significant development effort in the United States, where kerogen resources have never been developed on a large scale. In Europe, however, nuclear plants have been used for process heat delivery (district heating), and kerogen use is familiar in certain countries. Europe, China, and the United States all have the opportunity to use large scale NROSS development to enable major growth in renewable generation and either substantially reduce or eliminate their dependence on foreign fossil fuel supplies, accelerating their transitions to cleaner, more efficient, and more reliable energy systems.« less

Microgrid to enable optimal distributed energy retail and end-user demand response

DOE PAGES

Jin, Ming; Feng, Wei; Marnay, Chris; ...

2018-06-07

In the face of unprecedented challenges in environmental sustainability and grid resilience, there is an increasingly held consensus regarding the adoption of distributed and renewable energy resources such as microgrids (MGs), and the utilization of flexible electric loads by demand response (DR) to potentially drive a necessary paradigm shift in energy production and consumption patterns. However, the potential value of distributed generation and demand flexibility has not yet been fully realized in the operation of MGs. This study investigates the pricing and operation strategy with DR for a MG retailer in an integrated energy system (IES). Based on co-optimizing retailmore » rates and MG dispatch formulated as a mixed integer quadratic programming (MIQP) problem, our model devises a dynamic pricing scheme that reflects the cost of generation and promotes DR, in tandem with an optimal dispatch plan that exploits spark spread and facilitates the integration of renewables, resulting in improved retailer profits and system stability. Main issues like integrated energy coupling and customer bill reduction are addressed during pricing to ensure rates competitiveness and customer protection. By evaluating on real datasets, the system is demonstrated to optimally coordinate storage, renewables, and combined heat and power (CHP), reduce carbon dioxide emission while maintaining profits, and effectively alleviate the PV curtailment problem. Finally, the model can be used by retailers and MG operators to optimize their operations, as well as regulators to design new utility rates in support of the ongoing transformation of energy systems.« less

Development of a dynamic traffic assignment and simulation model for incident and emergency management applications in the Birmingham region : aim 3, emergency dispatchers' survey.

DOT National Transportation Integrated Search

2010-09-01

Traffic congestion is a primary concern during major incident and evacuation scenarios and can create difficulties for emergency vehicles attempting to enter and exit affected areas; however, many of the dispatchers who would be responsible for direc...

Airline Transport Pilot, Aircraft Dispatcher, and Flight Navigator. Question Book. Expires September 1, 1991.

ERIC Educational Resources Information Center

Federal Aviation Administration (DOT), Washington, DC.

This question book was developed by the Federal Aviation Administration (FAA) for testing applicants who are preparing for certification as airline transport pilots, aircraft dispatchers, or flight navigators. The publication contains several innovative features that are a departure from previous FAA publications related to air carrier personnel…

Dispatch No. 107 of 7 August 1989.

PubMed

1989-01-01

This Order prohibits the cutting, exploitation, and deforestation of "Pino Laso (Decussocarpus rospigliosii)" and other species of the family Podocarpaceae on all public and private property in Venezuela, except in limited and controlled circumstances. The preamble to the Dispatch states that trees of this species help to protect the sources of most of the country's water.

40 CFR 72.33 - Identification of dispatch system.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) PERMITS REGULATION Acid Rain Permit Applications § 72.33 Identification of dispatch system. (a... approval of the petition, all provisions of the Acid Rain Program applicable to an affected source or an... provision of the Acid Rain Program and shall not change the liability of the owners and operators of an...

40 CFR 72.33 - Identification of dispatch system.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) PERMITS REGULATION Acid Rain Permit Applications § 72.33 Identification of dispatch system. (a... approval of the petition, all provisions of the Acid Rain Program applicable to an affected source or an... provision of the Acid Rain Program and shall not change the liability of the owners and operators of an...

40 CFR 72.33 - Identification of dispatch system.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) PERMITS REGULATION Acid Rain Permit Applications § 72.33 Identification of dispatch system. (a... approval of the petition, all provisions of the Acid Rain Program applicable to an affected source or an... provision of the Acid Rain Program and shall not change the liability of the owners and operators of an...

40 CFR 72.33 - Identification of dispatch system.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) PERMITS REGULATION Acid Rain Permit Applications § 72.33 Identification of dispatch system. (a... approval of the petition, all provisions of the Acid Rain Program applicable to an affected source or an... provision of the Acid Rain Program and shall not change the liability of the owners and operators of an...

40 CFR 72.33 - Identification of dispatch system.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) PERMITS REGULATION Acid Rain Permit Applications § 72.33 Identification of dispatch system. (a... approval of the petition, all provisions of the Acid Rain Program applicable to an affected source or an... provision of the Acid Rain Program and shall not change the liability of the owners and operators of an...

14 CFR 121.615 - Dispatch or flight release over water: Flag and supplemental operations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Dispatch or flight release over water: Flag and supplemental operations. 121.615 Section 121.615 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS OPERATING...

Distributed problem solving by pilots and dispatchers

NASA Technical Reports Server (NTRS)

Orasanu, Judith; Wich, Mike; Fischer, Ute; Jobe, Kim; Mccoy, Elaine; Beatty, Roger; Smith, Phil

1993-01-01

The study addressed the following question: Are flight planning problems solved differently by PILOTS and DISPATCHERS when they work alone versus when they work together? Aspect of their performance that were of interest include the following: Problem perception and definition; Problem solving strategies and information use; Options considered; Solution and rational; and errors.

14 CFR 121.613 - Dispatch or flight release under IFR or over the top.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Dispatch or flight release under IFR or over the top. 121.613 Section 121.613 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... appropriate weather reports or forecasts, or any combination thereof, indicate that the weather conditions...

14 CFR 121.613 - Dispatch or flight release under IFR or over the top.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Dispatch or flight release under IFR or over the top. 121.613 Section 121.613 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... appropriate weather reports or forecasts, or any combination thereof, indicate that the weather conditions...

14 CFR 121.613 - Dispatch or flight release under IFR or over the top.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Dispatch or flight release under IFR or over the top. 121.613 Section 121.613 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... appropriate weather reports or forecasts, or any combination thereof, indicate that the weather conditions...

14 CFR 121.613 - Dispatch or flight release under IFR or over the top.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Dispatch or flight release under IFR or over the top. 121.613 Section 121.613 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... appropriate weather reports or forecasts, or any combination thereof, indicate that the weather conditions...

14 CFR 121.613 - Dispatch or flight release under IFR or over the top.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Dispatch or flight release under IFR or over the top. 121.613 Section 121.613 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... appropriate weather reports or forecasts, or any combination thereof, indicate that the weather conditions...

46 CFR 401.710 - Operating requirements for holders of Certificates of Authorization.

Code of Federal Regulations, 2010 CFR

2010-10-01

... of America and the Minister of Transport of Canada”, effective July 7, 1970, as amended; (c) Provide continuous arrangements and facilities for the efficient dispatching of pilotage service on a first-come, first-serve basis to vessels that give notice of pilotage service requirements to the pilotage dispatch...

The Australian electricity market's pre-dispatch process: Some observations on its efficiency using ordered probit model

NASA Astrophysics Data System (ADS)

Zainudin, Wan Nur Rahini Aznie; Becker, Ralf; Clements, Adam

2015-12-01

Many market participants in Australia Electricity Market had cast doubts on whether the pre-dispatch process in the electricity market is able to give them good and timely quantity and price information. In a study by [11], they observed a significant bias (mainly indicating that the pre-dispatch process tends to underestimate spot price outcomes), a seasonality features of the bias across seasons and/or trading periods and changes in bias across the years in our sample period (1999 to 2007). In a formal setting of an ordered probit model we establish that there are some exogenous variables that are able to explain increased probabilities of over- or under-predictions of the spot price. It transpires that meteorological data, expected pre-dispatch prices and information on past over- and under-predictions contribute significantly to explaining variation in the probabilities for over- and under-predictions. The results allow us to conjecture that some of the bids and re-bids provided by electricity generators are not made in good faith.

A Real-Time Greedy-Index Dispatching Policy for using PEVs to Provide Frequency Regulation Service

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

Ke, Xinda; Wu, Di; Lu, Ning

This article presents a real-time greedy-index dispatching policy (GIDP) for using plug-in electric vehicles (PEVs) to provide frequency regulation services. A new service cost allocation mechanism is proposed to award PEVs based on the amount of service they provided, while considering compensations for delayed-charging and reduction of battery lifetime due to participation of the service. The GIDP transforms the optimal dispatch problem from a high-dimensional space into a one-dimensional space while preserving the solution optimality. When solving the transformed problem in real-time, the global optimality of the GIDP solution can be guaranteed by mathematically proved “indexability”. Because the GIDP indexmore » can be calculated upon the PEV’s arrival and used for the entire decision making process till its departure, the computational burden is minimized and the complexity of the aggregator dispatch process is significantly reduced. Finally, simulation results are used to evaluate the proposed GIDP, and to demonstrate the potential profitability from providing frequency regulation service by using PEVs.« less

Review of Reactive Power Dispatch Strategies for Loss Minimization in a DFIG-based Wind Farm

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

Zhang, Baohua; Hu, Weihao; Hou, Peng

This study reviews and compares the performance of reactive power dispatch strategies for the loss minimization of Doubly Fed Induction Generator (DFIG)-based Wind Farms (WFs). Twelve possible combinations of three WF level reactive power dispatch strategies and four Wind Turbine (WT) level reactive power control strategies are investigated. All of the combined strategies are formulated based on the comprehensive loss models of WFs, including the loss models of DFIGs, converters, filters, transformers, and cables of the collection system. Optimization problems are solved by a Modified Particle Swarm Optimization (MPSO) algorithm. The effectiveness of these strategies is evaluated by simulations onmore » a carefully designed WF under a series of cases with different wind speeds and reactive power requirements of the WF. The wind speed at each WT inside the WF is calculated using the Jensen wake model. The results show that the best reactive power dispatch strategy for loss minimization comes when the WF level strategy and WT level control are coordinated and the losses from each device in the WF are considered in the objective.« less

Review of Reactive Power Dispatch Strategies for Loss Minimization in a DFIG-based Wind Farm

DOE PAGES

Zhang, Baohua; Hu, Weihao; Hou, Peng; ...

2017-06-27

This study reviews and compares the performance of reactive power dispatch strategies for the loss minimization of Doubly Fed Induction Generator (DFIG)-based Wind Farms (WFs). Twelve possible combinations of three WF level reactive power dispatch strategies and four Wind Turbine (WT) level reactive power control strategies are investigated. All of the combined strategies are formulated based on the comprehensive loss models of WFs, including the loss models of DFIGs, converters, filters, transformers, and cables of the collection system. Optimization problems are solved by a Modified Particle Swarm Optimization (MPSO) algorithm. The effectiveness of these strategies is evaluated by simulations onmore » a carefully designed WF under a series of cases with different wind speeds and reactive power requirements of the WF. The wind speed at each WT inside the WF is calculated using the Jensen wake model. The results show that the best reactive power dispatch strategy for loss minimization comes when the WF level strategy and WT level control are coordinated and the losses from each device in the WF are considered in the objective.« less

A Real-Time Greedy-Index Dispatching Policy for using PEVs to Provide Frequency Regulation Service

DOE PAGES

Ke, Xinda; Wu, Di; Lu, Ning

2017-09-18

This article presents a real-time greedy-index dispatching policy (GIDP) for using plug-in electric vehicles (PEVs) to provide frequency regulation services. A new service cost allocation mechanism is proposed to award PEVs based on the amount of service they provided, while considering compensations for delayed-charging and reduction of battery lifetime due to participation of the service. The GIDP transforms the optimal dispatch problem from a high-dimensional space into a one-dimensional space while preserving the solution optimality. When solving the transformed problem in real-time, the global optimality of the GIDP solution can be guaranteed by mathematically proved “indexability”. Because the GIDP indexmore » can be calculated upon the PEV’s arrival and used for the entire decision making process till its departure, the computational burden is minimized and the complexity of the aggregator dispatch process is significantly reduced. Finally, simulation results are used to evaluate the proposed GIDP, and to demonstrate the potential profitability from providing frequency regulation service by using PEVs.« less

On Why It Is Impossible to Prove that the BDX90 Dispatcher Implements a Time-sharing System

NASA Technical Reports Server (NTRS)

Boyer, R. S.; Moore, J. S.

1983-01-01

The Software Implemented Fault Tolerance SIFT system, is written in PASCAL except for about a page of machine code. The SIFT system implements a small time sharing system in which PASCAL programs for separate application tasks are executed according to a schedule with real time constraints. The PASCAL language has no provision for handling the notion of an interrupt such as the B930 clock interrupt. The PASCAL language also lacks the notion of running a PASCAL subroutine for a given amount of time, suspending it, saving away the suspension, and later activating the suspension. Machine code was used to overcome these inadequacies of PASCAL. Code which handles clock interrupts and suspends processes is called a dispatcher. The time sharing/virtual machine idea is completely destroyed by the reconfiguration task. After termination of the reconfiguration task, the tasks run by the dispatcher have no relation to those run before reconfiguration. It is impossible to view the dispatcher as a time-sharing system implementing virtual BDX930s running concurrently when one process can wipe out the others.

Multicriteria Selection of Optimal Location of TCSC in a Competitive Energy Market

NASA Astrophysics Data System (ADS)

Alomoush, Muwaffaq I.

2010-05-01

The paper investigates selection of the best location of thyristor-controlled series compensator (TCSC) in a transmission system from many candidate locations in a competitive energy market such that the TCSC causes a net valuable impact on congestion management outcome, transmission utilization, transmission losses, voltage stability, degree of fulfillment of spot market contracts, and system security. The problem is treated as a multicriteria decision-making process such that the candidate locations of TCSC are the alternatives and the conflicting objectives are the outcomes of the dispatch process, which may have different importance weights. The paper proposes some performance indices that the dispatch decision-making entity can use to measure market dispatch outcomes of each alternative. Based on agreed-upon preferences, the measures presented may help the decision maker compare and rank dispatch scenarios to ultimately decide which location is the optimal one. To solve the multicriteria decision, we use the preference ranking organization method for enrichment evaluations (PROMETHEE), which is a multicriteria decision support method that can handle complex conflicting-objective decision-making processes.

Review and future perspective of central receiver design and performance

NASA Astrophysics Data System (ADS)

Zhu, Guangdong; Libby, Cara

2017-06-01

Concentrating solar power (CSP) technology provides a commercial solar option to the utility-scale electricity market. CSP is unique in its ability to include low-cost thermal storage; thus, it can generate electricity when the sun is not available and dispatch electricity to meet varying load requirements. Within the suite of CSP technologies, the central receiver design represents the state-of-the-art technology, promising low cost, high performance, and dispatchable energy production. Current total capacity of central receiver plants worldwide is about 1.0 gigawatt (electric) with operating plants in Spain and the United States, as well as projects under construction in Asia, the Middle East, and North Africa. Central receiver technology has been under development since the 1950s, and a variety of central receiver designs have been explored. A distinguishing feature is the heat transfer medium. Central receiver designs exist that use dense fluids, gases, and solid particles in this role. Water/steam and molten salt receivers have been adopted in current commercial plants and are often coupled with a steam-Rankine power cycle with an operating temperature of less than 600°C. Many new central receiver concepts, such as the volumetric air, supercritical carbon dioxide (sCO2), solid particle, and liquid-metal receiver designs, are under active research and development (R&D). New designs target operating temperatures generally higher than 700°C-800°C—and even above 1000°C—so that higher-performance power cycles such as the sCO2-Brayton cycle or air-Brayton/steam-Rankine combined cycle can be used to promote greater overall system efficiency. Central receiver thermal storage provides dispatchability unavailable from variable-output renewables such as solar photovoltaic and wind power. Case study analysis of the California grid shows that there is a limit on the amount of non-dispatchable renewable generation that the grid can accommodate, beyond which overgeneration, spillage, and instability may occur. Energy storage may well become a necessity in some areas in order to maintain reliability. Next-generation central receiver technologies will have higher operating temperatures and additional features that allow higher-efficiency power generation and deliver other cost-performance advantages. The underlying innovations will come from areas such as multi-physics modeling, high-temperature materials, novel power cycles and heat exchanger designs, and collector field sensing and performance monitoring technologies. Technology innovation is expected to improve the cost and performance of central receiver designs. To deliver value as a generation and storage option, central receiver technology must also be supported by flexible and robust financial models and comprehensive energy and ancillary service markets justifying the capital-intensive investment. Progress in these areas will position CSP central receiver technology for future deployment.

Review and Future Perspective of Central Receiver Design and Performance

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

Zhu, Guangdong; Libby, Cara

Concentrating solar power (CSP) technology provides a commercial solar option to the utility-scale electricity market. CSP is unique in its ability to include low-cost thermal storage; thus, it can generate electricity when the sun is not available and dispatch electricity to meet varying load requirements. Within the suite of CSP technologies, the central receiver design represents the state-of-the-art technology, promising low cost, high performance, and dispatchable energy production. Current total capacity of central receiver plants worldwide is about 1.0 gigawatt (electric) with operating plants in Spain and the United States, as well as projects under construction in Asia, the Middlemore » East, and North Africa. Central receiver technology has been under development since the 1950s, and a variety of central receiver designs have been explored. A distinguishing feature is the heat transfer medium. Central receiver designs exist that use dense fluids, gases, and solid particles in this role. Water/steam and molten salt receivers have been adopted in current commercial plants and are often coupled with a steam-Rankine power cycle with an operating temperature of less than 600 degrees C. Many new central receiver concepts, such as the volumetric air, supercritical carbon dioxide (sCO2), solid particle, and liquid-metal receiver designs, are under active research and development (R&D). New designs target operating temperatures generally higher than 700 degrees C-800 degrees C -- and even above 1000 degrees C -- so that higher-performance power cycles such as the sCO2-Brayton cycle or air-Brayton/steam-Rankine combined cycle can be used to promote greater overall system efficiency. Central receiver thermal storage provides dispatchability unavailable from variable-output renewables such as solar photovoltaic and wind power. Case study analysis of the California grid shows that there is a limit on the amount of non-dispatchable renewable generation that the grid can accommodate, beyond which overgeneration, spillage, and instability may occur. Energy storage may well become a necessity in some areas in order to maintain reliability. Next-generation central receiver technologies will have higher operating temperatures and additional features that allow higher-efficiency power generation and deliver other cost-performance advantages. The underlying innovations will come from areas such as multi-physics modeling, high-temperature materials, novel power cycles and heat exchanger designs, and collector field sensing and performance monitoring technologies. Technology innovation is expected to improve the cost and performance of central receiver designs. To deliver value as a generation and storage option, central receiver technology must also be supported by flexible and robust financial models and comprehensive energy and ancillary service markets justifying the capital-intensive investment. Progress in these areas will position CSP central receiver technology for future deployment.« less

Bystander capability to activate speaker function for continuous dispatcher assisted CPR in case of suspected cardiac arrest.

PubMed

Steensberg, Alvilda T; Eriksen, Mette M; Andersen, Lars B; Hendriksen, Ole M; Larsen, Heinrich D; Laier, Gunnar H; Thougaard, Thomas

2017-06-01

The European Resuscitation Council Guidelines 2015 recommend bystanders to activate their mobile phone speaker function, if possible, in case of suspected cardiac arrest. This is to facilitate continuous dialogue with the dispatcher including (if required) cardiopulmonary resuscitation instructions. The aim of this study was to measure the bystander capability to activate speaker function in case of suspected cardiac arrest. In 87days, a systematic prospective registration of bystander capability to activate the speaker function, when cardiac arrest was suspected, was performed. For those asked, "can you activate your mobile phone's speaker function", audio recordings were examined and categorized into groups according to the bystanders capability to activate speaker function on their own initiative, without instructions, or with instructions from the emergency medical dispatcher. Time delay was measured, in seconds, for the bystanders without pre-activated speaker function. 42.0% (58) was able to activate the speaker function without instructions, 2.9% (4) with instructions, 18.1% (25) on own initiative and 37.0% (51) were unable to activate the speaker function. The median time to activate speaker function was 19s and 8s, with and without instructions, respectively. Dispatcher assisted cardiopulmonary resuscitation with activated speaker function, in cases of suspected cardiac arrest, allows for continuous dialogue between the emergency medical dispatcher and the bystander. In this study, we found a 63.0% success rate of activating the speaker function in such situations. Copyright © 2017 Elsevier B.V. All rights reserved.

The survival benefit of dual dispatch of EMS and fire-fighters in out-of-hospital cardiac arrest may differ depending on population density--a prospective cohort study.

PubMed

Nordberg, Per; Jonsson, Martin; Forsberg, Sune; Ringh, Mattias; Fredman, David; Riva, Gabriel; Hasselqvist-Ax, Ingela; Hollenberg, Jacob

2015-05-01

Outcome after out-of-hospital cardiac arrest (OHCA) varies between contexts. Dual dispatching of fire-fighters or police in addition to emergency medical services (EMS) has the potential to increase survival, but the effect in urban vs. rural areas is unknown. The aim of this study was to determine the effects of dual dispatching on response times and outcome in regions with different population density. The study design was a prospective cohort study of EMS-treated OHCAs from 2004 (historical controls, only EMS dispatch) and 2006-2009 (intervention, dual dispatch of EMS and fire-fighters), with data on exact geographical coordinates. Patients were divided into four subgroups depending on population density: rural (<250 persons/km2), suburban (250-2999/km2), urban (3000-5999/km2) and downtown (≥6000/km2). Totally, 2513 OHCAs were included (historical controls, n=571 and intervention, n=1942). Median time to arrival of first unit shortened significantly in all subgroups, ranging from 0.8 to 3.2 min, with the main time gain in the rural area. There were significant differences in 30-day survival between the historical controls vs. the intervention group in the suburban population (3.1% vs. 7.0%, p=0.02) and in downtown (4.1 vs. 14.6, p=0.04). In the urban population the difference was 2.7 vs. 6.9% (p=0.06) and in the rural population (4.7 vs. 5.3, p=0.82). Dual dispatch of fire-fighters and EMS in OHCA significantly reduced response times in all studied regions. The 30-day survival increased significantly in the downtown and suburban populations, while a limited impact was seen in the rural areas. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Bidding strategy for microgrid in day-ahead market based on hybrid stochastic/robust optimization

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

Liu, Guodong; Xu, Yan; Tomsovic, Kevin

In this paper, we propose an optimal bidding strategy in the day-ahead market of a microgrid consisting of intermittent distributed generation (DG), storage, dispatchable DG and price responsive loads. The microgrid coordinates the energy consumption or production of its components and trades electricity in both the day-ahead and real-time markets to minimize its operating cost as a single entity. The bidding problem is challenging due to a variety of uncertainties, including power output of intermittent DG, load variation, day-ahead and real-time market prices. A hybrid stochastic/robust optimization model is proposed to minimize the expected net cost, i.e., expected total costmore » of operation minus total benefit of demand. This formulation can be solved by mixed integer linear programming. The uncertain output of intermittent DG and day-ahead market price are modeled via scenarios based on forecast results, while a robust optimization is proposed to limit the unbalanced power in real-time market taking account of the uncertainty of real-time market price. Numerical simulations on a microgrid consisting of a wind turbine, a PV panel, a fuel cell, a micro-turbine, a diesel generator, a battery and a responsive load show the advantage of stochastic optimization in addition to robust optimization.« less

Bidding strategy for microgrid in day-ahead market based on hybrid stochastic/robust optimization

DOE PAGES

Liu, Guodong; Xu, Yan; Tomsovic, Kevin

2016-01-01

In this paper, we propose an optimal bidding strategy in the day-ahead market of a microgrid consisting of intermittent distributed generation (DG), storage, dispatchable DG and price responsive loads. The microgrid coordinates the energy consumption or production of its components and trades electricity in both the day-ahead and real-time markets to minimize its operating cost as a single entity. The bidding problem is challenging due to a variety of uncertainties, including power output of intermittent DG, load variation, day-ahead and real-time market prices. A hybrid stochastic/robust optimization model is proposed to minimize the expected net cost, i.e., expected total costmore » of operation minus total benefit of demand. This formulation can be solved by mixed integer linear programming. The uncertain output of intermittent DG and day-ahead market price are modeled via scenarios based on forecast results, while a robust optimization is proposed to limit the unbalanced power in real-time market taking account of the uncertainty of real-time market price. Numerical simulations on a microgrid consisting of a wind turbine, a PV panel, a fuel cell, a micro-turbine, a diesel generator, a battery and a responsive load show the advantage of stochastic optimization in addition to robust optimization.« less

Parameterizing the Variability and Uncertainty of Wind and Solar in CEMs

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

Frew, Bethany

We present current and improved methods for estimating the capacity value and curtailment impacts from variable generation (VG) in capacity expansion models (CEMs). The ideal calculation of these variability metrics is through an explicit co-optimized investment-dispatch model using multiple years of VG and load data. Because of data and computational limitations, existing CEMs typically approximate these metrics using a subset of all hours from a single year and/or using statistical methods, which often do not capture the tail-event impacts or the broader set of interactions between VG, storage, and conventional generators. In our proposed new methods, we use hourly generationmore » and load values across all hours of the year to characterize the (1) contribution of VG to system capacity during high load hours, (2) the curtailment level of VG, and (3) the reduction in VG curtailment due to storage and shutdown of select thermal generators. Using CEM model outputs from a preceding model solve period, we apply these methods to exogenously calculate capacity value and curtailment metrics for the subsequent model solve period. Preliminary results suggest that these hourly methods offer improved capacity value and curtailment representations of VG in the CEM from existing approximation methods without additional computational burdens.« less

Generation and Use of Thermal Energy in the Industrial Sector and Opportunities to Reduce its Carbon Emissions

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

McMillan, Colin; Boardman, Richard; McKellar, Michael

Changes are occurring throughout the U.S. economy, especially in regard to how energy is generated and used in the electricity, buildings, industrial, and transportation sectors. These changes are being driven by environmental and energy security concerns and by economics. The electric-sector market share of natural gas and variable renewable generation, such as wind and solar photovoltaics (PV), continues to grow. The buildings sector is evolving to meet efficiency standards, the transportation sector is evolving to meet efficiency and renewable fuels standards, and the industrial sector is evolving to reduce emissions. Those changes are driving investment and utilization strategies for generationmore » and other assets. Nuclear and renewable energy sources are important to consider in the energy sector’s evolution because both are considered to be clean and non-carbon-emitting energy sources. The Idaho National Laboratory (INL) and the National Renewable Energy Laboratory (NREL) are jointly investigating potential synergies between technologies exploiting nuclear and renewable energy sources. The two laboratories have held several joint workshops since 2011. Those workshops brought together experts in both areas to identify synergies and potential opportunities to work together. Workshop participants identified nuclear-renewable hybrid energy systems (N-R HESs) as one of the opportunities and recommended investigating whether N-R HESs could both generate dispatchable electricity without carbon emissions and provide clean energy to industrial processes. They also recommended analyzing the potential for N-R HESs to provide dispatchable capacity to a grid with high penetrations of non-dispatchable resources and to investigate whether real inertia provided by thermal power cycles within N-R HESs provides value to the grid. This report is one of a series of reports INL and NREL are producing to investigate the technical and economic aspects of N-R HESs. Previous reports focused on tightly coupled N-R HESs. Previously, INL analyzed the dynamic performance of two hypothetical N-R HESs and NREL analyzed the optimal economic configurations and operation of the same two N-R HESs. The first of those two is a Texas-synthetic gasoline scenario that includes four subsystems: a nuclear reactor, thermal power cycle, wind power plant, and synthetic gasoline production technology. The second hypothetical N-R HES is an Arizona-desalination scenario with four subsystems: a nuclear reactor, thermal power cycle, PV, and a desalination plant. INL analyzed the technical performance of the same two N-R HESs in another report. In another report NREL used the Texas-synthetic gasoline scenario provides the basis; however, the industrial process was removed. Instead, that N-R HES sells heat directly to an industrial customer. Subsystems that convert electricity to heat were also included. Future analyses are planned for other N-R HES options including one where hydrogen is produced within an N-R HES. This report quantifies greenhouse gas (GHG) emissions from the industrial sector and identifies opportunities for non-GHG-emitting thermal energy sources, such as N-R HESs, to replace the most significant GHG-emitting U.S. industries based on targeted, process-level analysis of industrial heat requirements.« less

Analysis of the methods for assessing socio-economic development level of urban areas

NASA Astrophysics Data System (ADS)

Popova, Olga; Bogacheva, Elena

2017-01-01

The present paper provides a targeted analysis of current approaches (ratings) in the assessment of socio-economic development of urban areas. The survey focuses on identifying standardized methodologies to area assessment techniques formation that will result in developing the system of intelligent monitoring, dispatching, building management, scheduling and effective management of an administrative-territorial unit. This system is characterized by complex hierarchical structure, including tangible and intangible properties (parameters, attributes). Investigating the abovementioned methods should increase the administrative-territorial unit's attractiveness for investors and residence. The research aims at studying methods for evaluating socio-economic development level of the Russian Federation territories. Experimental and theoretical territory estimating methods were revealed. Complex analysis of the characteristics of the areas was carried out and evaluation parameters were determined. Integral indicators (resulting rating criteria values) as well as the overall rankings (parameters, characteristics) were analyzed. The inventory of the most widely used partial indicators (parameters, characteristics) of urban areas was revealed. The resulting criteria of rating values homogeneity were verified and confirmed by determining the root mean square deviation, i.e. divergence of indices. The principal shortcomings of assessment methodologies were revealed. The assessment methods with enhanced effectiveness and homogeneity were proposed.

49 CFR 234.306 - Multiple dispatching or maintaining railroads with respect to the same highway-rail or pathway...

Code of Federal Regulations, 2012 CFR

2012-10-01

... respect to the same highway-rail or pathway grade crossing; appointment of responsible railroad. 234.306... Conditions at Highway-Rail and Pathway Grade Crossings § 234.306 Multiple dispatching or maintaining railroads with respect to the same highway-rail or pathway grade crossing; appointment of responsible...

49 CFR 234.306 - Multiple dispatching or maintaining railroads with respect to the same highway-rail or pathway...

Code of Federal Regulations, 2013 CFR

2013-10-01

... respect to the same highway-rail or pathway grade crossing; appointment of responsible railroad. 234.306... Conditions at Highway-Rail and Pathway Grade Crossings § 234.306 Multiple dispatching or maintaining railroads with respect to the same highway-rail or pathway grade crossing; appointment of responsible...

49 CFR 234.306 - Multiple dispatching or maintaining railroads with respect to the same highway-rail or pathway...

Code of Federal Regulations, 2014 CFR

2014-10-01

... respect to the same highway-rail or pathway grade crossing; appointment of responsible railroad. 234.306... Conditions at Highway-Rail and Pathway Grade Crossings § 234.306 Multiple dispatching or maintaining railroads with respect to the same highway-rail or pathway grade crossing; appointment of responsible...

17 CFR 240.17Ad-1 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-04-01

... or mails the item to, or the item is awaiting pick-up by, the presentor or a person designated by the... transfer agent dispatches or mails the item to, or the item is awaiting pick-up by, the outside registrar... registrar dispatches or mails the item to, or the item is awaiting pick-up by, the presenting transfer agent...

17 CFR 240.17Ad-1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-04-01

... or mails the item to, or the item is awaiting pick-up by, the presentor or a person designated by the... transfer agent dispatches or mails the item to, or the item is awaiting pick-up by, the outside registrar... registrar dispatches or mails the item to, or the item is awaiting pick-up by, the presenting transfer agent...

Model documentation: Electricity Market Module, Electricity Fuel Dispatch Submodule

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

Not Available

This report documents the objectives, analytical approach and development of the National Energy Modeling System Electricity Fuel Dispatch Submodule (EFD), a submodule of the Electricity Market Module (EMM). The report catalogues and describes the model assumptions, computational methodology, parameter estimation techniques, model source code, and forecast results generated through the synthesis and scenario development based on these components.

A methodology to identify stranded generation facilities and estimate stranded costs for Louisiana's electric utility industry

NASA Astrophysics Data System (ADS)

Cope, Robert Frank, III

1998-12-01

The electric utility industry in the United States is currently experiencing a new and different type of growing pain. It is the pain of having to restructure itself into a competitive business. Many industry experts are trying to explain how the nation as a whole, as well as individual states, will implement restructuring and handle its numerous "transition problems." One significant transition problem for federal and state regulators rests with determining a utility's stranded costs. Stranded generation facilities are assets which would be uneconomic in a competitive environment or costs for assets whose regulated book value is greater than market value. At issue is the methodology which will be used to estimate stranded costs. The two primary methods are known as "Top-Down" and "Bottom-Up." The "Top-Down" approach simply determines the present value of the losses in revenue as the market price for electricity changes over a period of time into the future. The problem with this approach is that it does not take into account technical issues associated with the generation and wheeling of electricity. The "Bottom-Up" approach computes the present value of specific strandable generation facilities and compares the resulting valuations with their historical costs. It is regarded as a detailed and difficult, but more precise, approach to identifying stranded assets and their associated costs. This dissertation develops a "Bottom-Up" quantitative, optimization-based approach to electric power wheeling within the state of Louisiana. It optimally evaluates all production capabilities and coordinates the movement of bulk power through transmission interconnections of competing companies in and around the state. Sensitivity analysis to this approach is performed by varying seasonal consumer demand, electric power imports, and transmission inter-connection cost parameters. Generation facility economic dispatch and transmission interconnection bulk power transfers, specific to each set of parameters, lead to the identification of stranded generation facilities. Stranded costs of non-dispatched and uneconomically dispatched generation facilities can then be estimated to indicate, arguably, the largest portion of restructuring transition costs as the industry is transformed from its present monopolistic structure to a competitive one.

Optimizing DER Participation in Inertial and Primary-Frequency Response

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

Dall-Anese, Emiliano; Zhao, Changhong; Guggilam, Swaroop

This paper develops an approach to enable the optimal participation of distributed energy resources (DERs) in inertial and primary-frequency response alongside conventional synchronous generators. Leveraging a reduced-order model description of frequency dynamics, DERs' synthetic inertias and droop coefficients are designed to meet time-domain performance objectives of frequency overshoot and steady-state regulation. Furthermore, an optimization-based method centered around classical economic dispatch is developed to ensure that DERs share the power injections for inertial- and primary-frequency response in proportion to their power ratings. Simulations for a modified New England test-case system composed of ten synchronous generators and six instances of the IEEEmore » 37-node test feeder with frequency-responsive DERs validate the design strategy.« less

Analysis and Application of Microgrids

NASA Astrophysics Data System (ADS)

Yue, Lu

New trends of generating electricity locally and utilizing non-conventional or renewable energy sources have attracted increasing interests due to the gradual depletion of conventional fossil fuel energy sources. The new type of power generation is called Distributed Generation (DG) and the energy sources utilized by Distributed Generation are termed Distributed Energy Sources (DERs). With DGs embedded in the distribution networks, they evolve from passive distribution networks to active distribution networks enabling bidirectional power flows in the networks. Further incorporating flexible and intelligent controllers and employing future technologies, active distribution networks will turn to a Microgrid. A Microgrid is a small-scale, low voltage Combined with Heat and Power (CHP) supply network designed to supply electrical and heat loads for a small community. To further implement Microgrids, a sophisticated Microgrid Management System must be integrated. However, due to the fact that a Microgrid has multiple DERs integrated and is likely to be deregulated, the ability to perform real-time OPF and economic dispatch with fast speed advanced communication network is necessary. In this thesis, first, problems such as, power system modelling, power flow solving and power system optimization, are studied. Then, Distributed Generation and Microgrid are studied and reviewed, including a comprehensive review over current distributed generation technologies and Microgrid Management Systems, etc. Finally, a computer-based AC optimization method which minimizes the total transmission loss and generation cost of a Microgrid is proposed and a wireless communication scheme based on synchronized Code Division Multiple Access (sCDMA) is proposed. The algorithm is tested with a 6-bus power system and a 9-bus power system.

Hydro power flexibility for power systems with variable renewable energy sources: an IEA Task 25 collaboration: Hydro power flexibility for power systems

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

Huertas-Hernando, Daniel; Farahmand, Hossein; Holttinen, Hannele

2016-06-20

Hydro power is one of the most flexible sources of electricity production. Power systems with considerable amounts of flexible hydro power potentially offer easier integration of variable generation, e.g., wind and solar. However, there exist operational constraints to ensure mid-/long-term security of supply while keeping river flows and reservoirs levels within permitted limits. In order to properly assess the effective available hydro power flexibility and its value for storage, a detailed assessment of hydro power is essential. Due to the inherent uncertainty of the weather-dependent hydrological cycle, regulation constraints on the hydro system, and uncertainty of internal load as wellmore » as variable generation (wind and solar), this assessment is complex. Hence, it requires proper modeling of all the underlying interactions between hydro power and the power system, with a large share of other variable renewables. A summary of existing experience of wind integration in hydro-dominated power systems clearly points to strict simulation methodologies. Recommendations include requirements for techno-economic models to correctly assess strategies for hydro power and pumped storage dispatch. These models are based not only on seasonal water inflow variations but also on variable generation, and all these are in time horizons from very short term up to multiple years, depending on the studied system. Another important recommendation is to include a geographically detailed description of hydro power systems, rivers' flows, and reservoirs as well as grid topology and congestion.« less

Relationship between Dongting Lake and surrounding rivers under the operation of the Three Gorges Reservoir, China.

PubMed

Zhan, Lucheng; Chen, Jiansheng; Zhang, Shiyin; Huang, Dewen; Li, Ling

2015-01-01

The natural flow properties of the Yangtze River have been changed completely following the construction of the Three Gorges Dam. The dam's operation has affected the resources and environment in the middle and lower reaches of the Yangtze River, changing the hydrological conditions and ecological environment of the Dongting Lake. During three different dispatching periods of the reservoir, we took triplicate samples of the river and lake water. All the samples were analysed for δ(2)H and δ(18)O to determine the relationship between the lake and the Yangtze River (and other rivers), and to evaluate objectively the influence of the dam's operation on the lake. During the period of water-supply dispatch, the Four Rivers and Miluo River are the main recharge sources of the lake. During the flood-storage dispatching period, the Dongting Lake is recharged largely by the Three Outlets and the Four Rivers, whereas during the period of water-storage dispatch, most of the lake's water originates from the Miluo, Xiang, Zi, and Yuan rivers. Although the Yangtze River only contributes significantly to the lake's recharge through the Three Outlets during the flood-storage dispatching period, the lake discharges large amounts of water into the Yangtze River during all three periods. Through the operation of the reservoir, it should be ensured that the water level of the Dongting Lake is not too low during the dry season, nor too high during the wet season, thus preventing the lake region from future flood and drought disasters.

Helicopter-based emergency medical services for a sparsely populated region: A study of 42,500 dispatches.

PubMed

Østerås, Ø; Brattebø, G; Heltne, J-K

2016-05-01

The Helicopter Emergency Medical Service (HEMS) in Norway is operated day and night, despite challenging geography and weather. In Western Norway, three ambulance helicopters, with a rapid response car as an alternative, cover close to 1 million inhabitants in an area of 45,000 km(2) . Our objective was to assess patterns of emergency medical problems and treatments in HEMS in a geographically large, but sparsely populated region. Data from all HEMS dispatches during 2004-2013 were assessed retrospectively. Information was analyzed with respect to patient treatment and characteristics, in addition to variations in services use during the day, week, and seasons. A total of 42,456 dispatches were analyzed. One third of the patients encountered were severely ill or injured, and two thirds of these received advanced treatment. Median activation time and on-scene time in primary helicopter missions were 5 and 11 min, respectively. Most patients (95%) were reached within 45 min by helicopter or rapid response car. Patterns of use did not change. More than one third of all dispatches were declined or aborted, mostly due to no longer medical indication, bad weather conditions, or competing missions. One third of the patients encountered were severely ill or injured, and more than two thirds of these received advanced treatment. HEMS use did not change over the 10-year period, however HEMS use peaked during daytime, weekends, and the summer. More than one third of all dispatches were declined or aborted. © 2015 The Authors. Acta Anaesthesiologica Scandinavica published by John Wiley & Sons Ltd on behalf of Acta Anaesthesiologica Scandinavica Foundation.

14 CFR 121.631 - Original dispatch or flight release, redispatch or amendment of dispatch or flight release.

Code of Federal Regulations, 2011 CFR

2011-01-01

... a flight to continue beyond the ETOPS Entry Point unless— (1) Except as provided in paragraph (d) of... with weather conditions at or above operating minima. (e) Before the ETOPS Entry Point, the pilot in... update the flight plan if needed because of a re-evaluation of aircraft system capabilities. (f) No...

14 CFR 121.631 - Original dispatch or flight release, redispatch or amendment of dispatch or flight release.

Code of Federal Regulations, 2012 CFR

2012-01-01

... a flight to continue beyond the ETOPS Entry Point unless— (1) Except as provided in paragraph (d) of... with weather conditions at or above operating minima. (e) Before the ETOPS Entry Point, the pilot in... update the flight plan if needed because of a re-evaluation of aircraft system capabilities. (f) No...

14 CFR 121.631 - Original dispatch or flight release, redispatch or amendment of dispatch or flight release.

Code of Federal Regulations, 2013 CFR

2013-01-01

... a flight to continue beyond the ETOPS Entry Point unless— (1) Except as provided in paragraph (d) of... with weather conditions at or above operating minima. (e) Before the ETOPS Entry Point, the pilot in... update the flight plan if needed because of a re-evaluation of aircraft system capabilities. (f) No...