WorldWideScience

Sample records for distributed energy storage

  1. ENERGY EFFICIENCY AND ENVIRONMENTALLY FRIENDLY DISTRIBUTED ENERGY STORAGE BATTERY

    Energy Technology Data Exchange (ETDEWEB)

    LANDI, J.T.; PLIVELICH, R.F.

    2006-04-30

    Electro Energy, Inc. conducted a research project to develop an energy efficient and environmentally friendly bipolar Ni-MH battery for distributed energy storage applications. Rechargeable batteries with long life and low cost potentially play a significant role by reducing electricity cost and pollution. A rechargeable battery functions as a reservoir for storage for electrical energy, carries energy for portable applications, or can provide peaking energy when a demand for electrical power exceeds primary generating capabilities.

  2. Distributed coordination of energy storage with distributed generators

    NARCIS (Netherlands)

    Yang, Tao; Wu, Di; Stoorvogel, Anton A.; Stoustrup, Jakob

    2016-01-01

    With a growing emphasis on energy efficiency and system flexibility, a great effort has been made recently in developing distributed energy resources (DER), including distributed generators and energy storage systems. This paper first formulates an optimal DER coordination problem considering constr

  3. Distributed Coordination of Energy Storage with Distributed Generators

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tao; Wu, Di; Stoorvogel, Antonie A.; Stoustrup, Jakob

    2016-07-18

    With a growing emphasis on energy efficiency and system flexibility, a great effort has been made recently in developing distributed energy resources (DER), including distributed generators and energy storage systems. This paper first formulates an optimal coordination problem considering constraints at both system and device levels, including power balance constraint, generator output limits, storage energy and power capacity and charging/discharging efficiencies. An algorithm is then proposed to dynamically and automatically coordinate DERs in a distributed manner. With the proposed algorithm, the agent at each DER only maintains a local incremental cost and updates it through information exchange with a few neighbors, without relying on any central decision maker. Simulation results are used to illustrate and validate the proposed algorithm.

  4. Energy storage system control strategies for power distribution systems

    Directory of Open Access Journals (Sweden)

    Areewan Kajorndech

    2015-03-01

    Full Text Available Energy storage systems have been widely employed to attain several benefits, such as reliability improvement, stabilization of power systems connected with renewable energy resources, economic benefits and etc. To achieve the above objectives, the appropriate and effective control strategies for energy storage systems are needed to be developed. This research proposes energy storage system control strategies for power distribution systems equipped with a limited size of energy storage system in order to improve reliability and save energy costs by determining an optimal charging schedule of the energy storage system. Simulation results demonstrate the benefits of energy storage system applications under the different control strategies.

  5. Energy Storage and Distributed Energy Generation Project, Final Project Report

    Energy Technology Data Exchange (ETDEWEB)

    Schwank, Johannes; Mader, Jerry; Chen, Xiaoyin; Mi, Chris; Linic, Suljo; Sastry, Ann Marie; Stefanopoulou, Anna; Thompson, Levi; Varde, Keshav

    2008-03-31

    This report serves as a Final Report under the “Energy Storage and Distribution Energy Generation Project” carried out by the Transportation Energy Center (TEC) at the University of Michigan (UM). An interdisciplinary research team has been working on fundamental and applied research on: -distributed power generation and microgrids, -power electronics, and -advanced energy storage. The long-term objective of the project was to provide a framework for identifying fundamental research solutions to technology challenges of transmission and distribution, with special emphasis on distributed power generation, energy storage, control methodologies, and power electronics for microgrids, and to develop enabling technologies for novel energy storage and harvesting concepts that can be simulated, tested, and scaled up to provide relief for both underserved and overstressed portions of the Nation’s grid. TEC’s research is closely associated with Sections 5.0 and 6.0 of the DOE "Five-year Program Plan for FY2008 to FY2012 for Electric Transmission and Distribution Programs, August 2006.”

  6. Energy storage system control strategies for power distribution systems

    OpenAIRE

    Areewan Kajorndech; Dulpichet Rerkpreedapong

    2015-01-01

    Energy storage systems have been widely employed to attain several benefits, such as reliability improvement, stabilization of power systems connected with renewable energy resources, economic benefits and etc. To achieve the above objectives, the appropriate and effective control strategies for energy storage systems are needed to be developed. This research proposes energy storage system control strategies for power distribution systems equipped with a limited size of energy storage system ...

  7. Advanced Energy Storage Management in Distribution Network

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guodong [ORNL; Ceylan, Oguzhan [ORNL; Xiao, Bailu [ORNL; Starke, Michael R [ORNL; Ollis, T Ben [ORNL; King, Daniel J [ORNL; Irminger, Philip [ORNL; Tomsovic, Kevin [University of Tennessee, Knoxville (UTK)

    2016-01-01

    With increasing penetration of distributed generation (DG) in the distribution networks (DN), the secure and optimal operation of DN has become an important concern. In this paper, an iterative mixed integer quadratic constrained quadratic programming model to optimize the operation of a three phase unbalanced distribution system with high penetration of Photovoltaic (PV) panels, DG and energy storage (ES) is developed. The proposed model minimizes not only the operating cost, including fuel cost and purchasing cost, but also voltage deviations and power loss. The optimization model is based on the linearized sensitivity coefficients between state variables (e.g., node voltages) and control variables (e.g., real and reactive power injections of DG and ES). To avoid slow convergence when close to the optimum, a golden search method is introduced to control the step size and accelerate the convergence. The proposed algorithm is demonstrated on modified IEEE 13 nodes test feeders with multiple PV panels, DG and ES. Numerical simulation results validate the proposed algorithm. Various scenarios of system configuration are studied and some critical findings are concluded.

  8. Distributed energy storage: Time-dependent tree flow design

    Science.gov (United States)

    Bejan, A.; Ziaei, S.; Lorente, S.

    2016-05-01

    This article proposes "distributed energy storage" as a basic design problem of distributing energy storage material on an area. The energy flows by fluid flow from a concentrated source to points (users) distributed equidistantly on the area. The flow is time-dependent. Several scenarios are analyzed: sensible-heat storage, latent-heat storage, exergy storage vs energy storage, and the distribution of a finite supply of heat transfer surface between the source fluid and the distributed storage material. The chief conclusion is that the finite amount of storage material should be distributed proportionally with the distribution of the flow rate of heating agent arriving on the area. The total time needed by the source stream to "invade" the area is cumulative (the sum of the storage times required at each storage site) and depends on the energy distribution paths and the sequence in which the users are served by the source stream. Directions for future designs of distributed storage and retrieval are outlined in the concluding section.

  9. Distributed Energy Systems with Wind Power and Energy Storage

    OpenAIRE

    Korpås, Magnus

    2004-01-01

    The topic of this thesis is the study of energy storage systems operating with wind power plants. The motivation for applying energy storage in this context is that wind power generation is intermittent and generally difficult to predict, and that good wind energy resources are often found in areas with limited grid capacity. Moreover, energy storage in the form of hydrogen makes it possible to provide clean fuel for transportation. The aim of this work has been to evaluate how local energy s...

  10. Distributed Energy Systems with Wind Power and Energy Storage

    OpenAIRE

    Korpås, Magnus

    2004-01-01

    The topic of this thesis is the study of energy storage systems operating with wind power plants. The motivation for applying energy storage in this context is that wind power generation is intermittent and generally difficult to predict, and that good wind energy resources are often found in areas with limited grid capacity. Moreover, energy storage in the form of hydrogen makes it possible to provide clean fuel for transportation. The aim of this work has been to evaluate how local energy s...

  11. Optimal Operation of Energy Storage in Power Transmission and Distribution

    OpenAIRE

    2015-01-01

    In this thesis, we investigate optimal operation of energy storage units in power transmission and distribution grids. At transmission level, we investigate the problem where an investor-owned independently-operated energy storage system seeks to offer energy and ancillary services in the day-ahead and real-time markets. We specifically consider the case where a significant portion of the power generated in the grid is from renewable energy resources and there exists significant uncertainty i...

  12. Distributed energy systems with wind power and energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Korpaas, Magnus

    2004-07-01

    The topic of this thesis is the study of energy storage systems operating with wind power plants. The motivation for applying energy storage in this context is that wind power generation is intermittent and generally difficult to predict, and that good wind energy resources are often found in areas with limited grid capacity. Moreover, energy storage in the form of hydrogen makes it possible to provide clean fuel for transportation. The aim of this work has been to evaluate how local energy storage systems should be designed and operated in order to increase the penetration and value of wind power in the power system. Optimization models and sequential and probabilistic simulation models have been developed for this purpose. Chapter 3 presents a sequential simulation model of a general wind hydrogen energy system. Electrolytic hydrogen is used either as a fuel for transportation or for power generation in a stationary fuel cell. The model is useful for evaluating how hydrogen storage can increase the penetration of wind power in areas with limited or no transmission capacity to the main grid. The simulation model is combined with a cost model in order to study how component sizing and choice of operation strategy influence the performance and economics of the wind-hydrogen system. If the stored hydrogen is not used as a separate product, but merely as electrical energy storage, it should be evaluated against other and more energy efficient storage options such as pumped hydro and redox flow cells. A probabilistic model of a grid-connected wind power plant with a general energy storage unit is presented in chapter 4. The energy storage unit is applied for smoothing wind power fluctuations by providing a firm power output to the grid over a specific period. The method described in the chapter is based on the statistical properties of the wind speed and a general representation of the wind energy conversion system and the energy storage unit. This method allows us to

  13. Global distribution of grid connected electrical energy storage systems

    Directory of Open Access Journals (Sweden)

    Katja Buss

    2016-06-01

    Full Text Available This article gives an overview of grid connected electrical energy storage systems worldwide, based on public available data. Technologies considered in this study are pumped hydroelectric energy storage (PHES, compressed air energy storage (CAES, sodium-sulfur batteries (NaS, lead-acid batteries, redox-flow batteries, nickel-cadmium batteries (NiCd and lithium-ion batteries. As the research indicates, the worldwide installed capacity of grid connected electrical energy storage systems is approximately 154 GW. This corresponds to a share of 5.5 % of the worldwide installed generation capacity. Furthermore, the article gives an overview of the historical development of installed and used storage systems worldwide. Subsequently, the focus is on each considered technology concerning the current storage size, number of plants and location. In summary it can be stated, PHES is the most commonly used technology worldwide, whereas electrochemical technologies are increasingly gaining in importance. Regarding the distribution of grid connected storage systems reveals the share of installed storage capacity is in Europe and Eastern Asia twice as high as in North America.

  14. Energy storage

    CERN Document Server

    Brunet, Yves

    2013-01-01

    Energy storage examines different applications such as electric power generation, transmission and distribution systems, pulsed systems, transportation, buildings and mobile applications. For each of these applications, proper energy storage technologies are foreseen, with their advantages, disadvantages and limits. As electricity cannot be stored cheaply in large quantities, energy has to be stored in another form (chemical, thermal, electromagnetic, mechanical) and then converted back into electric power and/or energy using conversion systems. Most of the storage technologies are examined: b

  15. Optimal Operation of Energy Storage in Power Transmission and Distribution

    Science.gov (United States)

    Akhavan Hejazi, Seyed Hossein

    In this thesis, we investigate optimal operation of energy storage units in power transmission and distribution grids. At transmission level, we investigate the problem where an investor-owned independently-operated energy storage system seeks to offer energy and ancillary services in the day-ahead and real-time markets. We specifically consider the case where a significant portion of the power generated in the grid is from renewable energy resources and there exists significant uncertainty in system operation. In this regard, we formulate a stochastic programming framework to choose optimal energy and reserve bids for the storage units that takes into account the fluctuating nature of the market prices due to the randomness in the renewable power generation availability. At distribution level, we develop a comprehensive data set to model various stochastic factors on power distribution networks, with focus on networks that have high penetration of electric vehicle charging load and distributed renewable generation. Furthermore, we develop a data-driven stochastic model for energy storage operation at distribution level, where the distribution of nodal voltage and line power flow are modelled as stochastic functions of the energy storage unit's charge and discharge schedules. In particular, we develop new closed-form stochastic models for such key operational parameters in the system. Our approach is analytical and allows formulating tractable optimization problems. Yet, it does not involve any restricting assumption on the distribution of random parameters, hence, it results in accurate modeling of uncertainties. By considering the specific characteristics of random variables, such as their statistical dependencies and often irregularly-shaped probability distributions, we propose a non-parametric chance-constrained optimization approach to operate and plan energy storage units in power distribution girds. In the proposed stochastic optimization, we consider

  16. Electric power processing, distribution, management and energy storage

    Science.gov (United States)

    Giudici, R. J.

    1980-01-01

    Power distribution subsystems are required for three elements of the SPS program: (1) orbiting satellite, (2) ground rectenna, and (3) Electric Orbiting Transfer Vehicle (EOTV). Power distribution subsystems receive electrical power from the energy conversion subsystem and provide the power busses rotary power transfer devices, switchgear, power processing, energy storage, and power management required to deliver control, high voltage plasma interactions, electric thruster interactions, and spacecraft charging of the SPS and the EOTV are also included as part of the power distribution subsystem design.

  17. Energy Storage.

    Science.gov (United States)

    Eaton, William W.

    Described are technological considerations affecting storage of energy, particularly electrical energy. The background and present status of energy storage by batteries, water storage, compressed air storage, flywheels, magnetic storage, hydrogen storage, and thermal storage are discussed followed by a review of development trends. Included are…

  18. Experimental Testing for Stability Analysis of Distributed Energy Resources Components with Storage Devices and Loads

    DEFF Research Database (Denmark)

    Mihet-Popa, Lucian; Groza, Voicu; Isleifsson, Fridrik Rafn

    2012-01-01

    Experimental Testing for Stability Analysis of Distributed Energy Resources Components with Storage Devices and Loads......Experimental Testing for Stability Analysis of Distributed Energy Resources Components with Storage Devices and Loads...

  19. Exergy efficient production, storage and distribution of solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Sandnes, Bjoernar

    2003-07-01

    There are two main themes in this thesis. 1) Exergy efficient utilization of solar energy, where the introduction of alternative technologies such as photovoltaic/thermal collectors and phase change energy storage in a low temperature solar system is investigated. 2) The possibility of storing thermal energy in supercooled liquids is investigated. The introductory chapters introduce the concept of exergy, and focus on the use of solar heat as an inherently low quality source for covering low quality demands associated with space heating and hot water. The different stages of solar energy production, storage, and distribution of heat is discussed, with emphasis on exergy relevant issues. With the low temperature solar heating system as background, the introduction of some additional technologies that are investigated. A section of this thesis presents a study of a small scale PV/T collector as a possible component in a low temperature system. In another section the instrumentation that has been built for studies of full-size PV and thermal systems is described, and the possibility of using the PV unit outputs as parameters for controlling the thermal system operation is briefly discussed. It is suggested that the design of the PV/T unit in terms of whether priority should be given to electricity or heat production should be based on how consumption of high quality auxiliary energy is minimized, and not on adding up the combined exergy which is being produced. Solar combisystems require larger heat storage capacities compared to the more common solar hot water systems. Increased volumetric heat storage capacity can be achieved by latent heat storage systems where thermal energy is stored as heat of fusion in phase change materials (PCMs). A section presents a study where spherically encapsulated PCM is incorporated in a solar heat store. Solar combisystems are often complex, and have a relatively large number of interacting components. Another section describes a

  20. Energy storage management system with distributed wireless sensors

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, Joseph C.; Bandhauer, Todd M.

    2015-12-08

    An energy storage system having a multiple different types of energy storage and conversion devices. Each device is equipped with one or more sensors and RFID tags to communicate sensor information wirelessly to a central electronic management system, which is used to control the operation of each device. Each device can have multiple RFID tags and sensor types. Several energy storage and conversion devices can be combined.

  1. Fuzzy droop control loops adjustment for stored energy balance in distributed energy storage system

    DEFF Research Database (Denmark)

    Aldana, Nelson Leonardo Diaz; Wu, Dan; Dragicevic, Tomislav;

    2015-01-01

    The study of isolated AC microgrid has been under high interest due to the integration of renewable energy resources especially for remote areas, or to improve the local energy reliability. The current trend is oriented to distributed renewable energy sources and their corresponding energy storage...... system, in order to smooth the variations at the prime energy generator. In this paper, a decentralized strategy based on fuzzy logic is proposed in order to balance the state of charge of distributed energy storage systems in lowvoltage three phase AC microgrid. The proposed method weights the action...... of conventional droop control loops for battery based distributed energy storage systems, in order to equalize their stored energy. The units are selfcontrolled by using local variables, hence, the microgrid can operate without communication systems. Frequency and voltage bus signaling are used in order...

  2. Economics of energy storage technology in active distribution networks

    National Research Council Canada - National Science Library

    CHEN, Jiongcong; SONG, Xudong

    2015-01-01

    .... The prioritization schemes of the combination of energy storage systems and intermittent energy systems were studied technically and economically based on some specific situations of the grid integrated with wind power...

  3. Distributed Energy Storage Control for Dynamic Load Impact Mitigation

    Directory of Open Access Journals (Sweden)

    Maximilian J. Zangs

    2016-08-01

    Full Text Available The future uptake of electric vehicles (EV in low-voltage distribution networks can cause increased voltage violations and thermal overloading of network assets, especially in networks with limited headroom at times of high or peak demand. To address this problem, this paper proposes a distributed battery energy storage solution, controlled using an additive increase multiplicative decrease (AIMD algorithm. The improved algorithm (AIMD+ uses local bus voltage measurements and a reference voltage threshold to determine the additive increase parameter and to control the charging, as well as discharging rate of the battery. The used voltage threshold is dependent on the network topology and is calculated using power flow analysis tools, with peak demand equally allocated amongst all loads. Simulations were performed on the IEEE LV European Test feeder and a number of real U.K. suburban power distribution network models, together with European demand data and a realistic electric vehicle charging model. The performance of the standard AIMD algorithm with a fixed voltage threshold and the proposed AIMD+ algorithm with the reference voltage profile are compared. Results show that, compared to the standard AIMD case, the proposed AIMD+ algorithm further improves the network’s voltage profiles, reduces thermal overload occurrences and ensures a more equal battery utilisation.

  4. Grid tie inverter energy stabilizing in smart distribution grid with energy storage

    Institute of Scientific and Technical Information of China (English)

    孙秋野; 李大双; 褚恩辉; 张艺缤

    2014-01-01

    With the growing deployment of smart distribution grid, it has become urgent to investigate the smart distribution grid behavior during transient faults and improve the system stability. The feasibility of segmenting large power grids and multiple smart distribution grids interconnections using energy storage technology for improving the system dynamic stability was studied. The segmentation validity of the large power grids and smart distribution grid inverter output interconnections power system using energy storage technology was proved in terms of theoretical analysis. Then, the influences of the energy storage device location and capacity on the proposed method were discussed in detail. The conclusion is obtained that the ESD optimal locations are allocated at the tie line terminal buses in the interconnected grid, respectively. The effectiveness of the proposed method was verified by simulations in an actual power system.

  5. Cost Benefit and Alternatives Analysis of Distribution Systems with Energy Storage Systems: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Tom; Nagarajan, Adarsh; Baggu, Murali; Bialek, Tom

    2017-06-27

    This paper explores monetized and non-monetized benefits from storage interconnected to distribution system through use cases illustrating potential applications for energy storage in California's electric utility system. This work supports SDG&E in its efforts to quantify, summarize, and compare the cost and benefit streams related to implementation and operation of energy storage on its distribution feeders. This effort develops the cost benefit and alternatives analysis platform, integrated with QSTS feeder simulation capability, and analyzed use cases to explore the cost-benefit of implementation and operation of energy storage for feeder support and market participation.

  6. Distributed energy. Conversion, storage and their development perspectives; Dezentrale Energie. Konversion, Speicherung und deren Entwicklungsperspektiven

    Energy Technology Data Exchange (ETDEWEB)

    Daschner, Robert; Apfelbacher, Andreas; Hornung, Andreas [Fraunhofer Institut fuer Umwelt-, Sicherheits- und Energietechnik UMSICHT, Sulzbach-Rosenberg (Germany)

    2015-11-01

    The energy transition (''Energiewende'') has already impact on the energy generation structure in Germany. In future, these trends are likely to intensify and distributed systems, such as wind, solar and also biomass and waste are increasingly going to generate energy. According to own simulations, it is foreseeable that the balance of energy demand increases sharply due to the high installed capacity, especially in wind power and PV systems in combination with their fluctuating generation. Due to the increasing surplus in electricity generation, energy has to be stored in the form of electricity, heat, but also chemically, because in this way, long-term storage and system transition of power to other forms of use, such as the chemical industry and mobility, can be achieved.

  7. Probabilistic tools for planning and operating power systems with distributed energy storage

    DEFF Research Database (Denmark)

    Klöckl, Bernd; Papaefthymiou, George; Pinson, Pierre

    2008-01-01

    Stochastic energy flows are an increasingly important phenomenon in today's power system planning and operation. They are – among other reasons – caused by large amounts of stochastic generation such as wind. The inclusion of energy storage devices, distributed in future systems (distributed energy...... owners are either the grid operators, the generation owners, or the energy traders. For the grid operators being the DES owners, storage operation will have to be integrated into the planning of the system, therefore multivariate nonparametric time series analysis and synthesis methods have to be applied...... to recorded data of stochastic energy resources. Together with suited storage models, the implications of DES on the planning of the system can then be assessed. For the producers or traders being the owners of the DES, the topic to be addressed is the real-time operation of each storage device in the power...

  8. Fuzzy Logic based Coordinated Control of Battery Energy Storage System and Dispatchable Distributed Generation for Microgrid

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Wang, Chengshan;

    2015-01-01

    Microgrid is an efficient solution to integraterenewable energy sources (RES) into power systems. Inorder to deal with the intermittent characteristics of therenewable energy based distributed generation (DG) units,a fuzzy-logic based coordinated control strategy of thebattery energy storage system...

  9. Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Mukundan, Rangachary [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-09-30

    Energy storage technology is critical if the U.S. is to achieve more than 25% penetration of renewable electrical energy, given the intermittency of wind and solar. Energy density is a critical parameter in the economic viability of any energy storage system with liquid fuels being 10 to 100 times better than batteries. However, the economical conversion of electricity to fuel still presents significant technical challenges. This project addressed these challenges by focusing on a specific approach: efficient processes to convert electricity, water and nitrogen to ammonia. Ammonia has many attributes that make it the ideal energy storage compound. The feed stocks are plentiful, ammonia is easily liquefied and routinely stored in large volumes in cheap containers, and it has exceptional energy density for grid scale electrical energy storage. Ammonia can be oxidized efficiently in fuel cells or advanced Carnot cycle engines yielding water and nitrogen as end products. Because of the high energy density and low reactivity of ammonia, the capital cost for grid storage will be lower than any other storage application. This project developed the theoretical foundations of N2 catalysis on specific catalysts and provided for the first time experimental evidence for activation of Mo 2N based catalysts. Theory also revealed that the N atom adsorbed in the bridging position between two metal atoms is the critical step for catalysis. Simple electrochemical ammonia production reactors were designed and built in this project using two novel electrolyte systems. The first one demonstrated the use of ionic liquid electrolytes at room temperature and the second the use of pyrophosphate based electrolytes at intermediate temperatures (200 – 300 ºC). The mechanism of high proton conduction in the pyrophosphate materials was found to be associated with a polyphosphate second phase contrary to literature claims and ammonia production rates as high as 5X 10

  10. Coordinated Control Scheme of Battery Energy Storage System (BESS) and Distributed Generations (DGs) for Electric Distribution Grid Operation

    DEFF Research Database (Denmark)

    Cha, Seung-Tae; Zhao, Haoran; Wu, Qiuwei

    2012-01-01

    This paper describes a coordinated control scheme of battery energy storage system (BESS) and distributed generations (DGs) for electric distribution grid operation. The BESS is designed to stabilize frequency and voltages as a primary control after the electric distribution system enters...

  11. Hierarchical predictive control scheme for distributed energy storage integrated with residential demand and photovoltaic generation

    NARCIS (Netherlands)

    Lampropoulos, I.; Garoufalis, P.; van den Bosch, P.P.J.; Kling, W.L.

    2015-01-01

    A hierarchical control scheme is defined for the energy management of a battery energy storage system which is integrated in a low-voltage distribution grid with residential customers and photovoltaic installations. The scope is the economic optimisation of the integrated system by employing predict

  12. Review on the Distributed Energy Storage Technology in the Application of the Micro Network

    Directory of Open Access Journals (Sweden)

    Huang Qiyuan

    2015-01-01

    Full Text Available This paper summarized the application process of energy storage technology in the micro-grid, elaborated on the development of energy storage technology concisely, and illustrated the roles of battery energy storage, flywheel energy storage, superconducting magnetic energy storage (SMES, super capacitor energy storage and other energy storage and so on in micro-hybrid. Then it compared the performances of some sorts of the storage method. As characteristics and actual demands of micro-grid work were given full into consideration, the current micro-grid energy storage technology research problems and development trend in the future were pointed out.

  13. Research on renewable energy power generation complementarity and storage distribution model

    Science.gov (United States)

    Wei, Xiaoxia; Zhang, Jinfang

    2017-01-01

    This paper mainly studied the equivalent conversion relationships and model of different “quality “energies in process of multi-energy conversion. In energy interconnection system containing wind turbine, photovoltaic cell and energy storage systems, it gives renewable energy and storage distribution development model, considering comprehensive effect of load demand characteristics on energy utilization mode, multi-objective optimization model is established with objectives of both maximized energy utilization ratio and minimized system operation costs. Then, take Chinese one certain area as scenario, and give out “renewable energy utilization“, “energy transfer” and “total operating cost” three different analyses, according to the connection model. The result is compared with that for traditional energy utilization model. Feasibility of the proposed model is verified with simulation results.

  14. Equalization Algorithm for Distributed Energy Storage Systems in Islanded AC Microgrids

    DEFF Research Database (Denmark)

    Aldana, Nelson Leonardo Diaz; Hernández, Adriana Carolina Luna; Quintero, Juan Carlos Vasquez

    2015-01-01

    This paper presents a centralized strategy for equalizing the state of charge of distributed energy storage systems in an islanded ac microgrid. The strategy is based on a simple algorithm denoted as equalization algorithm, which modifies the charge or discharge ratio on the time, for distributed...... energy storage systems, within a determined period of time in order to equalize the state of charge. The proposed approach has been tested in a MATLAB/Simulink model of the microgrid where the performance of the proposed strategy was verified....

  15. Highly efficient distributed generation and high-capacity energy storage

    DEFF Research Database (Denmark)

    Hemmes, Kas; Guerrero, Josep M.; Zhelev, Toshko

    2012-01-01

    With the growing amount of decentralized power production the design and operation of the grid has to be reconsidered. New problems include the two-way flow of electricity and maintaining the power balance given the increased amount of uncertain and fluctuating renewable energy sources like wind ...

  16. Distributed Storage Management Using Dynamic Pricing in a Self-Organized Energy Community

    NARCIS (Netherlands)

    Negeri, E.; Baken, N.

    2012-01-01

    We consider a future self-organized energy community that is composed of “prosumer” households that can autonomously generate, store, import and export power, and also selfishly strive to minimize their cost by adjusting their load profiles using the flexibly of their distributed storage. In such

  17. Distributed Demand Side Management with Battery Storage for Smart Home Energy Scheduling

    Directory of Open Access Journals (Sweden)

    Omowunmi Mary Longe

    2017-01-01

    Full Text Available The role of Demand Side Management (DSM with Distributed Energy Storage (DES has been gaining attention in recent studies due to the impact of the latter on energy management in the smart grid. In this work, an Energy Scheduling and Distributed Storage (ESDS algorithm is proposed to be installed into the smart meters of Time-of-Use (TOU pricing consumers possessing in-home energy storage devices. Source of energy supply to the smart home appliances was optimized between the utility grid and the DES device depending on energy tariff and consumer demand satisfaction information. This is to minimize consumer energy expenditure and maximize demand satisfaction simultaneously. The ESDS algorithm was found to offer consumer-friendly and utility-friendly enhancements to the DSM program such as energy, financial, and investment savings, reduced/eliminated consumer dissatisfaction even at peak periods, Peak-to-Average-Ratio (PAR demand reduction, grid energy sustainability, socio-economic benefits, and other associated benefits such as environmental-friendliness.

  18. Seasonal thermal energy storage

    Science.gov (United States)

    Allen, R. D.; Kannberg, L. D.; Raymond, J. R.

    1984-05-01

    Seasonal thermal energy storage (STES) using heat or cold available from surplus, waste, climatic, or cogeneration sources show great promise to reduce peak demand, reduce electric utility load problems, and contribute to establishing favorable economics for district heating and cooling systems. Heated and chilled water can be injected, stored, and recovered from aquifers. Geologic materials are good thermal insulators, and potentially suitable aquifers are distributed throughout the United States. Potential energy sources for use in an aquifer thermal energy storage system include solar heat, power plant cogeneration, winter chill, and industrial waste heat source. Topics covered include: (1) the U.S. Department of Energy seasonal thermal energy storage program; (2) aquifer thermal energy storage technology; (3) alternative STES technology; (4) foreign studies in seasonal thermal energy storage; and (5) economic assessment.

  19. Centralized Control Architecture for Coordination of Distributed Renewable Generation and Energy Storage in Islanded AC Microgrids

    DEFF Research Database (Denmark)

    Aldana, Nelson Leonardo Diaz; Hernández, Adriana Carolina Luna; Quintero, Juan Carlos Vasquez

    2017-01-01

    The coordinated operation of distributed energy resources such as storage and generation units and also loads is required for the reliable operation of an islanded microgrid. Since in islanded microgrids the storage units are commonly responsible for regulating the voltage amplitude and frequency...... in the local power system, the coordination should consider safe operating limits for the stored energy, which prevents fast degradation or damage to the storage units. This paper proposes a centralized control architecture, applicable for local area power systems such as a small-scale microgrid......, the strategy is complemented with an optimal scheduling of load connection, which minimizes the connection and disconnection cycles of the loads within a time horizon of 24 hours. The proposed architecture is verified experimentally in a lab-scale prototype of a microgrid, which has real communication between...

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

    Energy Technology Data Exchange (ETDEWEB)

    Lacommare, Kristina S H; Stadler, Michael; Aki, Hirohisa; Firestone, Ryan; Lai, Judy; Marnay, Chris; Siddiqui, Afzal

    2008-05-15

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

  1. SoC-Based Droop Method for Distributed Energy Storage in DC Microgrid Applications

    DEFF Research Database (Denmark)

    Lu, Xiaonan; Sun, Kai; Guerrero, Josep M.

    2012-01-01

    With the progress of distributed generation nowadays, microgrid is employed to integrate different renewable energy sources into a certain area. For several kinds of renewable sources have DC outputs, DC microgrid has drawn more attention recently. Meanwhile, to deal with the uncertainty...... in the output of microgrid system, distributed energy storage is usually adopted. Considering that the state-of-charge (SoC) of each battery may not be the same, decentralized droop control method based on SoC is shown in this paper to reach proportional load power sharing. With this method, the battery...

  2. Cooperative Management of a Lithium-Ion Battery Energy Storage Network: A Distributed MPC Approach

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Huazhen; Wu, Di; Yang, Tao

    2016-12-12

    This paper presents a study of cooperative power supply and storage for a network of Lithium-ion energy storage systems (LiBESSs). We propose to develop a distributed model predictive control (MPC) approach for two reasons. First, able to account for the practical constraints of a LiBESS, the MPC can enable a constraint-aware operation. Second, a distributed management can cope with a complex network that integrates a large number of LiBESSs over a complex communication topology. With this motivation, we then build a fully distributed MPC algorithm from an optimization perspective, which is based on an extension of the alternating direction method of multipliers (ADMM) method. A simulation example is provided to demonstrate the effectiveness of the proposed algorithm.

  3. Energy Conversion and Transmission Characteristics Analysis of Ice Storage Air Conditioning System Driven by Distributed Photovoltaic Energy System

    Directory of Open Access Journals (Sweden)

    Yongfeng Xu

    2016-01-01

    Full Text Available In order to reduce the investment and operation cost of distributed PV energy system, ice storage technology was introduced to substitute batteries for solar energy storage. Firstly, the ice storage air conditioning system (ISACS driven by distributed photovoltaic energy system (DPES was proposed and the feasibility studies have been investigated in this paper. And then, the theoretical model has been established and experimental work has been done to analyze the energy coupling and transferring characteristics in light-electricity-cold conversion process. In addition, the structure optimization analysis was investigated. Results revealed that energy losses were high in ice making process of ice slide maker with only 17.38% energy utilization efficiency and the energy efficiency and exergy efficiency of ISACS driven by DPES were 5.44% and 67.30%, respectively. So the immersed evaporator and cointegrated exchanger were adopted for higher energy utilization efficiency and better financial rewards in structure optimization. The COP and exergy efficiency of ice maker can be increased to 1.48 and 81.24%, respectively, after optimization and the energy utilization efficiency of ISACS driven by DPES could be improved 2.88 times. Moreover, ISACS has the out-of-the-box function of ordinary air conditioning system. In conclusion, ISACS driven by DPES will have good application prospects in tropical regions without power grid.

  4. Seasonal thermal energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Allen, R.D.; Kannberg, L.D.; Raymond, J.R.

    1984-05-01

    This report describes the following: (1) the US Department of Energy Seasonal Thermal Energy Storage Program, (2) aquifer thermal energy storage technology, (3) alternative STES technology, (4) foreign studies in seasonal thermal energy storage, and (5) economic assessment.

  5. Active and reactive power support of MV distribution systems using battery energy storage

    DEFF Research Database (Denmark)

    Wang, Jiawei; Hashemi Toghroljerdi, Seyedmostafa; You, Shi

    2017-01-01

    Adoption of Battery Energy Storage Systems (BESSs) for provision of grid services is increasing. This paper investigates the applications of BESS for the grid upgrade deferral and voltage support of Medium Voltage (MV) distribution systems. A BESS is modelled in Matlab/Simulink to perform peak load...... size for peak load shaving are investigated. The BESS annual lifetime degradation is also estimated using a rainflow counting algorithm. A reactive power support algorithm embedded with Q-U droop control is proposed in order to reduce the voltage drop in a part of 10 kV distribution network of Nordhavn...

  6. Multiagent Based Distributed Control for State-of-Charge Balance of Distributed Energy Storage in DC microgrids

    DEFF Research Database (Denmark)

    Li, Chendan; Dragicevic, Tomislav; Garcia Plaza, Manuel

    2014-01-01

    information for scheduling voltage autonomously. State-space analysis on a single energy storage unit and simulation verification shows that the proposed method has two advantages. Firstly, modifying the reference voltage given has less impact on system stability compared to gain scheduling. Secondly......In this paper, a distributed multiagent based algorithm is proposed to achieve SoC balance for DES in the DC microgrid by means of voltage scheduling. Reference voltage given is adjusted instead of droop gain. Dynamic average consensus algorithm is explored in each agent to get the required......, by adopting multiagent methodology, the proposed distributed control has less communication dependence and more reliable during communication topology changes....

  7. Distributed energy storage systems on the basis of electric-vehicle fleets

    Science.gov (United States)

    Zhuk, A. Z.; Buzoverov, E. A.; Sheindlin, A. E.

    2015-01-01

    Several power technologies directed to solving the problem of covering nonuniform loads in power systems are developed at the Joint Institute of High Temperatures, Russian Academy of Sciences (JIHT RAS). One direction of investigations is the use of storage batteries of electric vehicles to compensate load peaks in the power system (V2G—vehicle-to-grid technology). The efficiency of energy storage systems based on electric vehicles with traditional energy-saving technologies is compared in the article by means of performing computations. The comparison is performed by the minimum-cost criterion for the peak energy supply to the system. Computations show that the distributed storage systems based on fleets of electric cars are efficient economically with their usage regime to 1 h/day. In contrast to traditional methods, the prime cost of regulation of the loads in the power system based on V2G technology is independent of the duration of the load compensation period (the duration of the consumption peak).

  8. A Study on Applicability of Distributed Energy Generation, Storage and Consumption within Small Scale Facilities

    Directory of Open Access Journals (Sweden)

    Jesús Rodríguez-Molina

    2016-09-01

    Full Text Available Distributed generation and storage of energy, conceived as one of the prominent applications of the Smart Grid, has become one of the most popular ways for generation and usage of electricity. Not only does it offer environmental advantages and a more decentralized way to produce energy, but it also enables former consumers to become producers (thus turning them into prosumers. Alternatively, regular power production and consumption is still widely used in most of the world. Unfortunately, accurate business models representations and descriptive use cases for small scale facilitates, either involved in distributed energy or not, have not been provided in a descriptive enough manner. What is more, the possibilities that electricity trade and its storage and consumption activities offer for small users to obtain profits are yet to be addressed and offered to the research community in a thorough manner, so that small consumers will use them to their advantage. This paper puts forward a study on four different business models for small scale facilities and offers an economical study on how they can be deployed as a way to offer profitability for end users and new companies, while at the same time showing the required technological background to have them implemented.

  9. Battery cycle life balancing in a microgrid through flexible distribution of energy and storage resources

    Science.gov (United States)

    Khasawneh, Hussam J.; Illindala, Mahesh S.

    2014-09-01

    In this paper, a microgrid consisting of four fuel cell-battery hybrid Distributed Energy Resources (DERs) is devised for an industrial crusher-conveyor load. Each fuel cell was accompanied by a Li-ion battery to provide energy storage support under islanded condition of the microgrid since the fuel cells typically have poor transient response characteristics. After carrying out extensive modeling and analysis in MATLAB®, the battery utilization was found to vary significantly based on the DER's 'electrical' placement within the microgrid. This paper presents, under such conditions, a variety of battery life balancing solutions through the use of the new framework of Flexible Distribution of EneRgy and Storage Resources (FDERS). It is based on an in-situ reconfiguration approach through 'virtual' reactances that help in changing the 'electrical' position of each DER without physically displacing any component in the system. Several possible approaches toward balancing the battery utilization are compared in this paper taking advantage of the flexibility that FDERS offers. It was observed that the estimated battery life is dependent on factors such as cycling sequence, pattern, and occurrence.

  10. Temperature Distribution and Thermal Performance of an Aquifer Thermal Energy Storage System

    Science.gov (United States)

    Ganguly, Sayantan

    2017-04-01

    Energy conservation and storage has become very crucial to make use of excess energy during times of future demand. Excess thermal energy can be captured and stored in aquifers and this technique is termed as Aquifer Thermal Energy Storage (ATES). Storing seasonal thermal energy in water by injecting it into subsurface and extracting in time of demand is the principle of an ATES system. Using ATES systems leads to energy savings, reduces the dependency on fossil fuels and thus leads to reduction in greenhouse gas emission. This study numerically models an ATES system to store seasonal thermal energy and evaluates the performance of it. A 3D thermo-hydrogeological numerical model for a confined ATES system is presented in this study. The model includes heat transport processes of advection, conduction and heat loss to confining rock media. The model also takes into account regional groundwater flow in the aquifer, geothermal gradient and anisotropy in the aquifer. Results show that thermal injection into the aquifer results in the generation of a thermal-front which grows in size with time. Premature thermal-breakthrough causes thermal interference in the system when the thermal-front reaches the production well and consequences in the fall of system performance and hence should be avoided. This study models the transient temperature distribution in the aquifer for different flow and geological conditions. This may be effectively used in designing an efficient ATES project by ensuring safety from thermal-breakthrough while catering to the energy demand. Based on the model results a safe well spacing is proposed. The thermal energy discharged by the system is determined and strategy to avoid the premature thermal-breakthrough in critical cases is discussed. The present numerical model is applied to simulate an experimental field study which is found to approximate the field results quite well.

  11. Optimal Scheduling of a Battery Energy Storage System with Electric Vehicles’ Auxiliary for a Distribution Network with Renewable Energy Integration

    Directory of Open Access Journals (Sweden)

    Yuqing Yang

    2015-09-01

    Full Text Available With global conventional energy depletion, as well as environmental pollution, utilizing renewable energy for power supply is the only way for human beings to survive. Currently, distributed generation incorporated into a distribution network has become the new trend, with the advantages of controllability, flexibility and tremendous potential. However, the fluctuation of distributed energy resources (DERs is still the main concern for accurate deployment. Thus, a battery energy storage system (BESS has to be involved to mitigate the bad effects of DERs’ integration. In this paper, optimal scheduling strategies for BESS operation have been proposed, to assist with consuming the renewable energy, reduce the active power loss, alleviate the voltage fluctuation and minimize the electricity cost. Besides, the electric vehicles (EVs considered as the auxiliary technique are also introduced to attenuate the DERs’ influence. Moreover, both day-ahead and real-time operation scheduling strategies were presented under the consideration with the constraints of BESS and the EVs’ operation, and the optimization was tackled by a fuzzy mathematical method and an improved particle swarm optimization (IPSO algorithm. Furthermore, the test system for the proposed strategies is a real distribution network with renewable energy integration. After simulation, the proposed scheduling strategies have been verified to be extremely effective for the enhancement of the distribution network characteristics.

  12. Battery energy storage technologies

    Science.gov (United States)

    Anderson, Max D.; Carr, Dodd S.

    1993-03-01

    Battery energy storage systems, comprising lead-acid batteries, power conversion systems, and control systems, are used by three main groups: power generating utilities, power distributing utilities, and major power consumers (such as electric furnace foundries). The principal advantages of battery energy storage systems to generating utilities include load leveling, frequency control, spinning reserve, modular construction, convenient siting, no emissions, and investment deferral for new generation and transmission equipment. Power distributing utilities and major power consumers can avoid costly demand changes by discharging their batteries at peak periods and then recharging with lower cost off-peak power (say, at night). Battery energy storage systems are most cost effective when designed for discharge periods of less than 5 h; other systems (for example, pumped water storage) are better suited for longer discharges. It is estimated that by the year 2000 there will be a potential need for 4000 MW of battery energy storage. New construction of five plants totaling 100 MW is presently scheduled for completion by the Puerto Rico Electric Power Authority between 1992 and 1995.

  13. Stability Analysis of DC Distribution Systems with Droop-Based Charge Sharing on Energy Storage Devices

    Directory of Open Access Journals (Sweden)

    Despoina I. Makrygiorgou

    2017-03-01

    Full Text Available Direct current (DC distribution systems and DC microgrids are becoming a reliable and efficient alternative energy system, compatible with the DC nature of most of the distributed energy resources (DERs, storage devices and loads. The challenging problem of redesigning an autonomous DC-grid system in view of using energy storage devices to balance the power produced and absorbed, by applying simple decentralized controllers on the electronic power interfaces, is investigated in this paper. To this end, a complete nonlinear DC-grid model has been deployed that includes different DC-DERs, two controlled parallel battery branches, and different varying DC loads. Since many loads in modern distribution systems are connected through power converters, both constant power loads and simple resistive loads are considered in parallel. Within this system, suitable cascaded controllers on the DC/DC power converter interfaces to the battery branches are proposed, in a manner that ensures stability and charge sharing between the two branches at the desired ratio. To achieve this task, inner-loop current controllers are combined with outer-loop voltage, droop-based controllers. The proportional-integral (PI inner-loop current controllers include damping terms and are fully independent from the system parameters. The controller scheme is incorporated into the system model and a globally valid nonlinear stability analysis is conducted; this differs from small-signal linear methods that are valid only for specific systems, usually via eigenvalue investigations. In the present study, under the virtual cost of applying advanced Lyapunov techniques on the entire nonlinear system, a rigorous analysis is formulated to prove stability and convergence to the desired operation, regardless of the particular system characteristics. The theoretical results are evaluated by detailed simulations, with the system performance being very satisfactory.

  14. Distributed Control of Battery Energy Storage Systems for Voltage Regulation in Distribution Networks with High PV Penetration

    DEFF Research Database (Denmark)

    Zeraati, Mehdi; Golshan, Mohamad Esmaeil Hamedani; Guerrero, Josep M.

    2017-01-01

    issues of distribution networks. In this paper, the battery energy storage (BES) systems are used in order to solve the voltage rise during the peak PV generation as well as the voltage drop while meeting the peak load. A coordinated control strategy is proposed to regulate the charge/discharge of BESs...... using a combination of the local droop based control method and a distributed control scheme which ensures the voltages of feeder remain within allowed limits. Therefore, two different consensus algorithms are used: The first algorithm determines the BESs participation in voltage regulation in terms......The voltage rise problem in low voltage (LV) distribution networks with high penetration of photovoltaic (PV) resources is one of the most important challenges in the development of these renewable resources since it may prevent the maximum PV penetration considering the reliability and security...

  15. Estimating electricity storage power rating and discharge duration for utility transmission and distribution deferral :a study for the DOE energy storage program.

    Energy Technology Data Exchange (ETDEWEB)

    Eyer, James M. (Distributed Utility Associates, Livermore, CA); Butler, Paul Charles; Iannucci, Joseph J., Jr. (,.Distributed Utility Associates, Livermore, CA)

    2005-11-01

    This report describes a methodology for estimating the power and energy capacities for electricity energy storage systems that can be used to defer costly upgrades to fully overloaded, or nearly overloaded, transmission and distribution (T&D) nodes. This ''sizing'' methodology may be used to estimate the amount of storage needed so that T&D upgrades may be deferred for one year. The same methodology can also be used to estimate the characteristics of storage needed for subsequent years of deferral.

  16. Distribution of energy storage rate in area of strain localization during tension of austenitic steel

    Science.gov (United States)

    Oliferuk, W.; Maj, M.; Zembrzycki, K.

    2015-01-01

    The present work is devoted to experimental determination of the energy storage rate in the area of strain localization. The experimental procedure involves two complementary techniques: i.e. infrared thermography (IRT) and visible light imaging. The results of experiments have shown that during the evolution of plastic strain localization the energy storage rate in some areas of the deformed specimen drops to zero. To interpret the decrease of the energy storage rate in terms of micro-mechanisms, microstructural observations using electron back scattered diffraction (EBSC) were performed.

  17. Distributed demand-side management optimisation for multi-residential users with energy production and storage strategies

    Directory of Open Access Journals (Sweden)

    Emmanuel Chifuel Manasseh

    2014-12-01

    Full Text Available This study considers load control in a multi-residential setup where energy scheduler (ES devices installed in smart meters are employed for demand-side management (DSM. Several residential end-users share the same energy source and each residential user has non-adjustable loads and adjustable loads. In addition, residential users may have storage devices and renewable energy sources such as wind turbines or solar as well as dispatchable generators. The ES devices exchange information automatically by executing an iterative distributed algorithm to locate the optimal energy schedule for each end-user. This will reduce the total energy cost and the peak-to-average ratio (PAR in energy demand in the electric power distribution. Users possessing storage devices and dispatchable generators strategically utilise their resources to minimise the total energy cost together with the PAR. Simulation results are provided to evaluate the performance of the proposed game theoretic-based distributed DSM technique.

  18. Impact of Electric Vehicles as Distributed Energy Storage in Isolated Systems: The Case of Tenerife

    Directory of Open Access Journals (Sweden)

    Alfredo Ramírez Díaz

    2015-11-01

    Full Text Available Isolated regions are highly dependent on fossil fuels. The use of endogenous sources and the improvement in energy efficiency in all of the consumption activities are the two main ways to reduce the dependence of petroleum-derived fuels. Tenerife offers an excellent renewable resource (hours of sun and wind. However, the massive development of these technologies could cause important operational problems within the electric power grids, because of the small size of the system. In this paper, we explore the option of coupling an electric vehicle fleet as a distributed energy storage system to increase the participation of renewables in an isolated power system, i.e., Tenerife Island. A model simulator has been used to evaluate five key outputs, that is the renewable share, the energy spilled, the CO2 emissions, the levelized cost of generating electricity and fuel dependence, under alternative scenarios. Comparing to the current situation, combining a gradual renewable installed capacity and the introduction of an electric vehicle fleet using alternative charging strategies, a total of 30 different scenarios have been evaluated. Results shows that the impact of 50,000 electric vehicles would increase the renewable share in the electricity mix of the island up to 30%, reduce CO2 emissions by 27%, the total cost of electric generation by 6% and the oil internal market by 16%.

  19. Electric utility transmission and distribution upgrade deferral benefits from modular electricity storage : a study for the DOE Energy Storage Systems Program.

    Energy Technology Data Exchange (ETDEWEB)

    Eyer, James M. (Distributed Utility Associates, Inc., Livermore, CA)

    2009-06-01

    The work documented in this report was undertaken as part of an ongoing investigation of innovative and potentially attractive value propositions for electricity storage by the United States Department of Energy (DOE) and Sandia National Laboratories (SNL) Electricity Storage Systems (ESS) Program. This study characterizes one especially attractive value proposition for modular electricity storage (MES): electric utility transmission and distribution (T&D) upgrade deferral. The T&D deferral benefit is characterized in detail. Also presented is a generalized framework for estimating the benefit. Other important and complementary (to T&D deferral) elements of possible value propositions involving MES are also characterized.

  20. Energy Management System with Equalization Algorithm for Distributed Energy Storage Systems in PV-Active Generator Based Low Voltage DC Microgrids

    DEFF Research Database (Denmark)

    Aldana, Nelson Leonardo Diaz; Hernández, Adriana Carolina Luna; Vasquez, Juan Carlos

    2015-01-01

    resistor of local droop control loops at each distributed energy storage system. The proposed strategy, can be used as an additional function of the microgrid energy management system where the state of charge of distributed ESS is equalized within a determined window of time. Finally, real-time simulation...

  1. Redesign Electricity Market for the Next Generation Power System of Renewable Energy and Distributed Storage Technologies

    DEFF Research Database (Denmark)

    Feng, Donghan; Xu, Zhao; Østergaard, Jacob

    2010-01-01

    This paper proposes a stochastic time-series based method to simulate the volatility of intermittent renewable generation and distributed storage devices along timeline. The proposed method can calculate the optimal timeline for different electricity markets and power systems. In practice...

  2. Voltage Scheduling Droop Control for State-of-Charge Balance of Distributed Energy Storage in DC Microgrids

    DEFF Research Database (Denmark)

    Li, Chendan; Dragicevic, Tomislav; Aldana, Nelson Leonardo Diaz

    2014-01-01

    the State-of-Charge balance. In this paper, a new droop method based on voltage scheduling for State-of-Charge balance is proposed to keep the SoC balance for the energy storage units. The proposed method has the advantage of avoiding the stability problem existed in traditional methods based on droop gain...... scheduling. Simulation experiment is taken in Matlab on a DC microgrid with two distributed energy storage units. The simulation results show that the proposed method has successfully achieved SoC balance during the load changes while maintaining the DC bus voltage within the allowable range....

  3. Maui energy storage study.

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, James; Bhatnagar, Dhruv; Karlson, Benjamin

    2012-12-01

    This report investigates strategies to mitigate anticipated wind energy curtailment on Maui, with a focus on grid-level energy storage technology. The study team developed an hourly production cost model of the Maui Electric Company (MECO) system, with an expected 72 MW of wind generation and 15 MW of distributed photovoltaic (PV) generation in 2015, and used this model to investigate strategies that mitigate wind energy curtailment. It was found that storage projects can reduce both wind curtailment and the annual cost of producing power, and can do so in a cost-effective manner. Most of the savings achieved in these scenarios are not from replacing constant-cost diesel-fired generation with wind generation. Instead, the savings are achieved by the more efficient operation of the conventional units of the system. Using additional storage for spinning reserve enables the system to decrease the amount of spinning reserve provided by single-cycle units. This decreases the amount of generation from these units, which are often operated at their least efficient point (at minimum load). At the same time, the amount of spinning reserve from the efficient combined-cycle units also decreases, allowing these units to operate at higher, more efficient levels.

  4. Systems, distribution and storage

    Energy Technology Data Exchange (ETDEWEB)

    Altiparmakis, A.; Nygaard Rasmussen, C.; Pensini, A.; Marra, F.; Guang Ya Yang

    2012-11-15

    Energy storage is as yet somewhat unprofitable due to its high capital costs and the immaturity of the technology. However, it shows great promise because of its expected ability to cut costs, deal with issues of excess energy supply from intermittent renewable sources, and capture profits from price arbitrage in electricity and heat markets. (LN)

  5. Thermal energy storage

    Science.gov (United States)

    1980-01-01

    The planning and implementation of activities associated with lead center management role and the technical accomplishments pertaining to high temperature thermal energy storage subsystems are described. Major elements reported are: (1) program definition and assessment; (2) research and technology development; (3) industrial storage applications; (4) solar thermal power storage applications; and (5) building heating and cooling applications.

  6. Distributed Generation Integration in the Electric Grid: Energy Storage System for Frequency Control

    Directory of Open Access Journals (Sweden)

    Maurizio Delfanti

    2014-01-01

    Full Text Available During the last few years generation from renewable energy sources (RESs has grown considerably in European electrical networks. Transmission system operators are greatly concerned about the impact of RESs on the operational security and efficiency of their networks and more in general of the ENTSO-E interconnected system. Grid codes are to be revised in order to harmonise the rules regarding the connection of RES power plants. A main issue concerns frequency control: frequency is greatly affected by RESs intermittency and its deviations must be limited as much as possible in order to guarantee a suitable level of power quality. To improve frequency stability, in the future, Grid codes could extend frequency control requirements also to RES units, whereas today they are applied only to conventional power plants. Energy storage systems can be a possible solution to increase the flexibility and performance of RES power plants: they allow generators to modulate their power injections without wasting renewable energy. In this paper, the authors studied the suitability of extending frequency control to RES units integrating them with energy storage systems. In particular, the paper focuses on the impact of frequency control on the storage lifetime by analysing the power charge/discharge in response to real frequency oscillations.

  7. Bearingless AC Homopolar Machine Design and Control for Distributed Flywheel Energy Storage

    Science.gov (United States)

    Severson, Eric Loren

    The increasing ownership of electric vehicles, in-home solar and wind generation, and wider penetration of renewable energies onto the power grid has created a need for grid-based energy storage to provide energy-neutral services. These services include frequency regulation, which requires short response-times, high power ramping capabilities, and several charge cycles over the course of one day; and diurnal load-/generation-following services to offset the inherent mismatch between renewable generation and the power grid's load profile, which requires low self-discharge so that a reasonable efficiency is obtained over a 24 hour storage interval. To realize the maximum benefits of energy storage, the technology should be modular and have minimum geographic constraints, so that it is easily scalable according to local demands. Furthermore, the technology must be economically viable to participate in the energy markets. There is currently no storage technology that is able to simultaneously meet all of these needs. This dissertation focuses on developing a new energy storage device based on flywheel technology to meet these needs. It is shown that the bearingless ac homopolar machine can be used to overcome key obstacles in flywheel technology, namely: unacceptable self-discharge and overall system cost and complexity. Bearingless machines combine the functionality of a magnetic bearing and a motor/generator into a single electromechanical device. Design of these machines is particularly challenging due to cross-coupling effects and trade-offs between motor and magnetic bearing capabilities. The bearingless ac homopolar machine adds to these design challenges due to its 3D flux paths requiring computationally expensive 3D finite element analysis. At the time this dissertation was started, bearingless ac homopolar machines were a highly immature technology. This dissertation advances the state-of-the-art of these machines through research contributions in the areas of

  8. 主动配电网储能优化规划%Optimized energy storage planning of active distribution network

    Institute of Scientific and Technical Information of China (English)

    刘波; 邱晓燕

    2016-01-01

    大量分布式电源的接入使得主动配电网成为现有配电网的发展趋势及方向,可再生能源发电的间歇性将会提高配电网的风险,解决这些问题最有效的方法就是配置适当的储能装置,合理地优化配置储能装置不仅能提升主动配电网对分布式能源的消纳能力还能提高主动配电网运行的稳定性。主动配电网储能长期优化规划以短期优化为基础,短期优化考虑了储能系统的削峰填谷及调节馈线节点电压水平的能力从而决定储能的额定功率,长期优化规划模型以主动配电网经济运行成本最小为目标函数考虑储能投资成本以及主动配电网的运行成本及可靠性成本,通过禁忌搜索-粒子群混合算法求解得到电池储能装置的最优位置、容量及额定功率,算例验证了所提模型及其求解方法的可行性。%Accessing to large number of distributed generators makes the active distribution network become the development trend and direction of existing distribution network.The intermittence of renewable energy generation will increase the risk of distribution network. To solve this problem,the most effective solution is to configure the distribution network with appropriate energy storage device. Optimizing the allocation of energy storage device reasonably can not only promote the distributed energy absorption ability of active distribution network,but also improve the stability of the active distribution network operation.The long-term optimization planning of active distribution network energy storage is based on the short-term optimization,the short-term optimization considers the peak and valley load shifting of the energy storage system and the capability of adjusting feeder node voltage level to determine the rated power of energy storage.The long time optimization planning model takes the minimum economic operation cost of the active distribution network as the objective

  9. Energy storage systems impact on the short-term frequency stability of distributed autonomous microgrids, an analysis using aggregate models

    DEFF Research Database (Denmark)

    Serban, Ioan; Teodorescu, Remus; Marinescu, Corneliu

    2013-01-01

    of storing and releasing energy when required by the system. Therefore the need of boosting the MG power reserves by adding energy storage systems is often a requirement. The study highlights the improvement in the MG short-term frequency stability brought by an original BESS control structure enhanced......This study analyses the integration impact of battery energy storage systems (BESSs) on the short-term frequency control in autonomous microgrids (MGs). Short-term frequency stability relates with the primary or speed control level, as defined in the regulations of the classical grids. The focus...... is on autonomous MGs that dynamically behave similarly to the classical power systems. This is the systems case with classical distributed generators (DGs), but which can also contain renewable energy sources (RESs) in a certain penetration level. During MG islanded operation, the local generators take over most...

  10. Spacecraft Energy Storage Systems

    OpenAIRE

    Robinson, Wilf; Hanks, James; Spina, Len; Havenhill, Doug; Gisler, Gary; Ginter, Steve; Brault, Sharon

    1997-01-01

    Flywheel Energy Storage Systems represent an exciting alternative to traditional battery storage systems used to power satellites during periods of eclipse. The increasing demand for reliable communication and data access is driving explosive growth in the number of satellite systems being developed as well as their performance requirements. Power on orbit is the key to this performance, and batteries are becoming increasingly unattractive as an energy storage media. Flywheel systems offer ve...

  11. Simulation models developed for voltage control in a distribution network using energy storage systems for PV penetration

    DEFF Research Database (Denmark)

    Mihet-Popa, Lucian; Bindner, Henrik W.

    2013-01-01

    This paper presents the development of simulation models for DER components in a distribution network, with focus on voltage controllers using energy storage systems for PV penetration. The Vanadium Redox Battery (VRB) system model, used as an energy storage system, was implemented in MATLAB....../Simulink and DIgSILENT PowerFactory, based on the efficiency of different components-such as: cell stacks, electrolytes, pumps and power converters, whilst power losses were also taken into account. The simulation results have been validated against measurements using experimental facility of a distributed power...... system laboratory. To study the variability and the interaction between feeders including VRB, PV system and active units an overvoltage controller has also been developed, implemented and tested successfully....

  12. Distributed MPC for Efficient Coordination of Storage and Renewable Energy Sources Across Control Areas

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Kyri; Guo, Junyao; Hug, Gabriela; Li, Xin

    2016-03-01

    In electric power systems, multiple entities are responsible for ensuring an economic and reliable way of delivering power from producers to consumers. With the increase of variable renewable generation it is becoming increasingly important to take advantage of the individual entities' (and their areas') capabilities for balancing variability. Hence, in this paper, we employ and extend the approximate Newton directions method to optimally coordinate control areas leveraging storage available in one area to balance variable resources in another area with only minimal information exchange among the areas. The problem to be decomposed is a model predictive control problem including generation constraints, energy storage constraints, and AC power flow constraints. Singularity issues encountered when formulating the respective Newton-Raphson steps due to intertemporal constraints are addressed and extensions to the original decomposition method are proposed to improve the convergence rate and required communication of the method.

  13. State-of-Charge Balance Using Adaptive Droop Control for Distributed Energy Storage Systems in DC MicroGrid Applications

    DEFF Research Database (Denmark)

    Lu, Xiaonan; Sun, Kai; Guerrero, Josep M.

    2014-01-01

    This paper presents the coordinated control of distributed energy storage systems (DESSs) in DC micro-grids. In order to balance the state-of-charge (SoC) of each energy storage unit (ESU), an SoC-based adaptive droop control method is proposed. In this decentralized control method, the droop...... coefficient is inversely proportional to the nth order of SoC. By using SoC-based droop method, the ESUs with higher SoC deliver more power, while the ones with lower SoC deliver less power. Therefore, the energy stored in the ESU with higher SoC decreases faster than that with lower SoC. The SoC difference...... and the system stability is thereby analyzed by using this model. Simulation and experimental results from a 2×2.2 kW parallel converter system are presented in order to validate the proposed approach....

  14. Optimizing Capacities of Distributed Generation and Energy Storage in a Small Autonomous Power System Considering Uncertainty in Renewables

    Directory of Open Access Journals (Sweden)

    Ying-Yi Hong

    2015-03-01

    Full Text Available This paper explores real power generation planning, considering distributed generation resources and energy storage in a small standalone power system. On account of the Kyoto Protocol and Copenhagen Accord, wind and photovoltaic (PV powers are considered as clean and renewable energies. In this study, a genetic algorithm (GA was used to determine the optimal capacities of wind-turbine-generators, PV, diesel generators and energy storage in a small standalone power system. The investment costs (installation, unit and maintenance costs of the distributed generation resources and energy storage and the cost of fuel for the diesel generators were minimized while the reliability requirement and CO2 emission limit were fulfilled. The renewable sources and loads were modeled by random variables because of their uncertainties. The equality and inequality constraints in the genetic algorithms were treated by cumulant effects and cumulative probability of random variables, respectively. The IEEE reliability data for an 8760 h load profile with a 150 kW peak load were used to demonstrate the applicability of the proposed method.

  15. Solar Energy: Heat Storage.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on heat storage is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

  16. Southern company energy storage study :

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, James; Bhatnagar, Dhruv; Black, Clifton; Jenkins, Kip

    2013-03-01

    This study evaluates the business case for additional bulk electric energy storage in the Southern Company service territory for the year 2020. The model was used to examine how system operations are likely to change as additional storage is added. The storage resources were allowed to provide energy time shift, regulation reserve, and spinning reserve services. Several storage facilities, including pumped hydroelectric systems, flywheels, and bulk-scale batteries, were considered. These scenarios were tested against a range of sensitivities: three different natural gas price assumptions, a 15% decrease in coal-fired generation capacity, and a high renewable penetration (10% of total generation from wind energy). Only in the elevated natural gas price sensitivities did some of the additional bulk-scale storage projects appear justifiable on the basis of projected production cost savings. Enabling existing peak shaving hydroelectric plants to provide regulation and spinning reserve, however, is likely to provide savings that justify the project cost even at anticipated natural gas price levels. Transmission and distribution applications of storage were not examined in this study. Allowing new storage facilities to serve both bulk grid and transmission/distribution-level needs may provide for increased benefit streams, and thus make a stronger business case for additional storage.

  17. Wind-energy storage

    Science.gov (United States)

    Gordon, L. H.

    1980-01-01

    Program SIMWEST can model wind energy storage system using any combination of five types of storage: pumped hydro, battery, thermal, flywheel, and pneumatic. Program is tool to aid design of optional system for given application with realistic simulation for further evaluation and verification.

  18. Energy Storage Economics

    Energy Technology Data Exchange (ETDEWEB)

    Elgqvist, Emma M [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-07

    This presentation provides an overview on energy storage economics including recent market trends, battery terminology and concepts, value streams, challenges, and an example of how photovoltaics and storage can be used to lower demand charges. It also provides an overview of the REopt Lite web tool inputs and outputs.

  19. Co-generation and innovative heat storage systems in small-medium CSP plants for distributed energy production

    Science.gov (United States)

    Giaconia, Alberto; Montagnino, Fabio; Paredes, Filippo; Donato, Filippo; Caputo, Giampaolo; Mazzei, Domenico

    2017-06-01

    CSP technologies can be applied for distributed energy production, on small-medium plants (on the 1 MW scale), to satisfy the needs of local communities, buildings and districts. In this perspective, reliable, low-cost, and flexible small/medium multi-generative CSP plants should be developed. Four pilot plants have been built in four Mediterranean countries (Cyprus, Egypt, Jordan, and Italy) to demonstrate the approach. In this paper, the plant built in Italy is presented, with specific innovations applied in the linear Fresnel collector design and the Thermal Energy Storage (TES) system, based on a single the use of molten salts but specifically tailored for small scale plants.

  20. Electrochemical Energy Storage Branch

    Science.gov (United States)

    1985-01-01

    The activities of the Electrochemical Energy Storage Branch are highlighted, including the Technology Base Research and the Exploratory Technology Development and Testing projects within the Electrochemical Energy Storage Program for the 1984 fiscal year. General Headquarters activities are presented first; and then, a summary of the Director Controlled Milestones, followed by other major accomplishments. A listing of the workshops and seminars held during the year is also included.

  1. Technology Roadmap: Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-03-01

    Energy storage technologies are valuable components in most energy systems and could be an important tool in achieving a low-carbon future. These technologies allow for the decoupling of energy supply and demand, in essence providing a valuable resource to system operators. There are many cases where energy storage deployment is competitive or near-competitive in today's energy system. However, regulatory and market conditions are frequently ill-equipped to compensate storage for the suite of services that it can provide. Furthermore, some technologies are still too expensive relative to other competing technologies (e.g. flexible generation and new transmission lines in electricity systems). One of the key goals of this new roadmap is to understand and communicate the value of energy storage to energy system stakeholders. This will include concepts that address the current status of deployment and predicted evolution in the context of current and future energy system needs by using a ''systems perspective'' rather than looking at storage technologies in isolation.

  2. Electrochemical energy storage

    CERN Document Server

    Tarascon, Jean-Marie

    2015-01-01

    The electrochemical storage of energy has become essential in assisting the development of electrical transport and use of renewable energies. French researchers have played a key role in this domain but Asia is currently the market leader. Not wanting to see history repeat itself, France created the research network on electrochemical energy storage (RS2E) in 2011. This book discusses the launch of RS2E, its stakeholders, objectives, and integrated structure that assures a continuum between basic research, technological research and industries. Here, the authors will cover the technological

  3. Decentralized Monitoring and Control of Electric Power Distribution System with a use case of Community Energy Storage System

    Science.gov (United States)

    Huq, Kazi Mohammad Moyeenull

    This work focuses on the platform and framework required for developing decentralized monitoring and control applications for a distribution system. Decentralized control of Community Energy Storage (CES) devices has been considered as a use case. The first chapter gives an overview of energy management system and applications. Then the development of centralized and decentralized CES control applications are discussed. The next chapters discusses the software architecture of a typical centralized SCADAEMS platform and outlines the architecture required for a decentralized platform. Then, suitability of IEC 61850 standard for decentralized monitoring and control is investigated and an approach to developing decentralized applications in IEC 61850 enabled environment is proposed and demonstrated. Finally, CIM standard is reviewed for exchanging power system topology information for distributed control.

  4. A Distributed Energy System Based on Wind Energy Storage%一种基于风能储能的分布式能源系统

    Institute of Scientific and Technical Information of China (English)

    王凯; 张远; 孙燕平; 杨科

    2013-01-01

    In order to verify and study the output characteristics of distributed energy system based on the integration system of wind power generation and Advanced Adiabatic Compressed Air Energy Storage (AA-CAES),a distributed energy system with wind energy storage technology was established and parametric expressions about energy were deduced thermodynamically. The relationship between the output characteristics of distributed energy system and heat energy utilization was determined , and advantages of distributed energy system were analyzed with an example of one office building .Results show that power is decreasing with heating increasing , meanwhile cooling and the total energy output are increasing; compared with the model of power , the total energy output of distributed energy model are more on the premise of ensuring the demand of cooling and heat ,and distributed energy model is more energy-efficient when the total energy output are the same .%为了验证和分析风电与先进绝热压缩空气储能( Advanced Adiabatic Compressed Air Energy Storage ,简称AA-CAES)集成系统用于分布式供能的能量输出特性,建立了以风能储能技术为基础的分布式能源系统模型,从热力学角度推导了与能量输出相关的参数表达式,得到了分布式能源系统冷热电输出特性与储热器中热量利用的关联性,并以某写字楼为例,分析了分布式能源系统的优势。结果表明:随系统供热量的增加,系统供电量减少,制冷量增加,且能量输出总量增加;在满足冷量和热量需求的前提下,相比供电模型,分布式供能模型有更多的供电量,而在能量输出相同的条件下,分布式能源系统模型更节能。

  5. Energy storage connection system

    Science.gov (United States)

    Benedict, Eric L.; Borland, Nicholas P.; Dale, Magdelena; Freeman, Belvin; Kite, Kim A.; Petter, Jeffrey K.; Taylor, Brendan F.

    2012-07-03

    A power system for connecting a variable voltage power source, such as a power controller, with a plurality of energy storage devices, at least two of which have a different initial voltage than the output voltage of the variable voltage power source. The power system includes a controller that increases the output voltage of the variable voltage power source. When such output voltage is substantially equal to the initial voltage of a first one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the first one of the energy storage devices. The controller then causes the output voltage of the variable voltage power source to continue increasing. When the output voltage is substantially equal to the initial voltage of a second one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the second one of the energy storage devices.

  6. Superconducting magnetic energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, J.D.

    1976-01-01

    Fusion power production requires energy storage and transfer on short time scales to create confining magnetic fields and for heating plasmas. The theta-pinch Scyllac Fusion Test Reactor (SFTR) requires 480 MJ of energy to drive the 5-T compression field with a 0.7-ms rise time. Tokamak Experimental Power Reactors (EPR) require 1 to 2 GJ of energy with a 1 to 2-s rise time for plasma ohmic heating. The design, development, and testing of four 300-kJ energy storage coils to satisfy the SFTR needs are described. Potential rotating machinery and homopolar energy systems for both the Reference Theta-Pinch Reactor (RTPR) and tokamak ohmic-heating are presented.

  7. Issue Brief: A Survey of State Policies to Support Utility-Scale and Distributed-Energy Storage (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-09-01

    This document summarizes proposed and enacted legislation and activities related to energy storage for nine states, which are presented alphabetically. These states were selected to provide a high-level view of various energy storage efforts taking place across the United States.

  8. Optimal Active Power Control of A Wind Farm Equipped with Energy Storage System based on Distributed Model Predictive Control

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Guo, Qinglai

    2016-01-01

    This paper presents the Distributed Model Predictive Control (D-MPC) of a wind farm equipped with fast and short-term Energy Storage System (ESS) for optimal active power control using the fast gradient method via dual decomposition. The primary objective of the D-MPC control of the wind farm...... is power reference tracking from system operators. Besides, by optimal distribution of the power references to individual wind turbines and the ESS unit, the wind turbine mechanical loads are alleviated. With the fast gradient method, the convergence rate of the DMPC is significantly improved which leads...... is independent from the wind farm size and is suitable for the real-time control of the wind farm with ESS....

  9. Optimal Scheduling for the Complementary Energy Storage System Operation Based on Smart Metering Data in the DC Distribution System

    Directory of Open Access Journals (Sweden)

    Bokyung Ko

    2013-12-01

    Full Text Available The increasing penetration of distributed generation (DG sources in low-voltage grid feeders causes problems concerning voltage regulation. The penetration of DG sources such as photovoltaics (PVs in the distribution system can significantly impact the power flow and voltage conditions on the customer side. As the DG sources are more commonly connected to low-voltage distribution systems, voltage fluctuations in the distribution system are experienced because of the DG fluctuation and uncertainty. Therefore, the penetration of DGs in distribution systems is often limited by the required operating voltage ranges. By using an energy storage system (ESS, voltage fluctuation can be compensated for, thus satisfying the voltage regulation requirements. This paper presents an ESS scheduling algorithm based on the power injection data obtained from a smart metering system. The proposed ESS scheduling algorithm is designed for use within a direct current (DC distribution grid, which comprises customers, each with a PV and an ESS system. The purpose of this ESS scheduling algorithm is to optimize the ESS scheduling by considering the complementary operation among all the ESSs.

  10. A Distributed Control Strategy Based on DC Bus Signaling for Modular Photovoltaic Generation Systems With Battery Energy Storage

    DEFF Research Database (Denmark)

    Sun, Kai; Zhang, Li; Xing, Yan

    2011-01-01

    Modular generation system, which consists of modular power conditioning converters, is an effective solution to integrate renewable energy sources with conventional utility grid to improve reliability and efficiency, especially for photovoltaic generation. A distributed control strategy based...... on improved dc bus signaling is proposed for a modular photovoltaic (PV) generation system with battery energy storage elements. In this paper, the modular PV generation system is composed of three modular dc/dc converters for PV arrays, two grid-connected dc/ac converters, and one dc/dc converter for battery......, grid-connected inversion, and islanding with constant voltage (CV) generation.The power balance of the system under extreme conditions such as the islanding operation with a full-charged battery is taken into account in this control strategy. The dc bus voltage level is employed as an information...

  11. NV energy electricity storage valuation :

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, James F.; Bhatnagar, Dhruv; Samaan, Nader; Jin, Chunlian

    2013-06-01

    This study examines how grid-level electricity storage may benefit the operations of NV Energy, and assesses whether those benefits are likely to justify the cost of the storage system. To determine the impact of grid-level storage, an hourly production cost model of the Nevada Balancing Authority ("BA") as projected for 2020 was created. Storage was found to add value primarily through the provision of regulating reserve. Certain storage resources were found likely to be cost-effective even without considering their capacity value, as long as their effectiveness in providing regulating reserve was taken into account. Giving fast resources credit for their ability to provide regulating reserve is reasonable, given the adoption of FERC Order 755 ("Pay-for-performance"). Using a traditional five-minute test to determine how much a resource can contribute to regulating reserve does not adequately value fast-ramping resources, as the regulating reserve these resources can provide is constrained by their installed capacity. While an approximation was made to consider the additional value provided by a fast-ramping resource, a more precise valuation requires an alternate regulating reserve methodology. Developing and modeling a new regulating reserve methodology for NV Energy was beyond the scope of this study, as was assessing the incremental value of distributed storage.

  12. Energy Storage Project

    Science.gov (United States)

    Mercer, Carolyn R.; Jankovsky, Amy L.; Reid, Concha M.; Miller, Thomas B.; Hoberecht, Mark A.

    2011-01-01

    NASA's Exploration Technology Development Program funded the Energy Storage Project to develop battery and fuel cell technology to meet the expected energy storage needs of the Constellation Program for human exploration. Technology needs were determined by architecture studies and risk assessments conducted by the Constellation Program, focused on a mission for a long-duration lunar outpost. Critical energy storage needs were identified as batteries for EVA suits, surface mobility systems, and a lander ascent stage; fuel cells for the lander and mobility systems; and a regenerative fuel cell for surface power. To address these needs, the Energy Storage Project developed advanced lithium-ion battery technology, targeting cell-level safety and very high specific energy and energy density. Key accomplishments include the development of silicon composite anodes, lithiated-mixed-metal-oxide cathodes, low-flammability electrolytes, and cell-incorporated safety devices that promise to substantially improve battery performance while providing a high level of safety. The project also developed "non-flow-through" proton-exchange-membrane fuel cell stacks. The primary advantage of this technology set is the reduction of ancillary parts in the balance-of-plant--fewer pumps, separators and related components should result in fewer failure modes and hence a higher probability of achieving very reliable operation, and reduced parasitic power losses enable smaller reactant tanks and therefore systems with lower mass and volume. Key accomplishments include the fabrication and testing of several robust, small-scale nonflow-through fuel cell stacks that have demonstrated proof-of-concept. This report summarizes the project s goals, objectives, technical accomplishments, and risk assessments. A bibliography spanning the life of the project is also included.

  13. Technical and economic analysis on grid-connected wind farm based on hybrid energy storage system and distributed generators

    Science.gov (United States)

    Zhang, Xinhua; Zhou, Zhongkang; Chen, Xiaochun; Song, Jishuang; Shi, Maolin

    2017-05-01

    system is proposed based on NaS battery and lithium ion battery, that the former is the main large scale energy storage technology world-widely used and developed and the latter is a flexible way to have both power and energy capacities. The hybrid energy storage system, which takes advantage of the two complementary technologies to provide large power and energy capacities, is chosen to do an evaluation of econom ical-environmental based on critical excess electricity production (CEEP), CO2 emission, annual total costs calculated on the specific given condition using Energy PLAN software. The result shows that hybrid storage system has strengths in environmental benefits and also can absorb more discarded wind power than single storage system and is a potential way to push forward the application of wind power and even other types of renewable energy resources.

  14. Pseudocapacitors for Energy Storage

    Science.gov (United States)

    Venkataraman, Anuradha

    Fluctuation in the demand for electrical power and the intermittent nature of the supply of energy from renewable sources like solar and wind have made the need for energy storage a dire necessity. Current storage technologies like batteries and supercapacitors fall short either in terms of power output or in their ability to store sufficient energy. Pseudocapacitors combine features of both and offer an alternative to stabilize the power supply. They possess high rates of charge and discharge and are capable of storing much more energy in comparison to a supercapacitor. In the quest for solutions that are economical and feasible, we have investigated Prussian Blue in aqueous electrolytes for its use as a pseudocapacitor. Two different active materials based on Prussian Blue were prepared; one that has just Prussian Blue and the other that contains a mixture of Prussian Blue and carbon nanotubes (CNTs). Four electrolytes differing in the valence of the cation were employed for the study. Cyclic voltammetry and galvanostatic charge-discharge were used to characterize the electrodes. Our experiments have shown specific capacitances of Prussian Blue electrodes in the range of 140-720 F/g and that of Prussian Blue-CNT electrodes in the range of ˜52 F/g. The remarkable capacity of charge storage in Prussian Blue electrodes is attributed to its electrochemical activity ensuring surface redox and its tunnel-like structure allowing ease of entry and exit for ions like Potassium. Simple methods of synthesis have yielded specific capacitances of the order of hundreds of Farads per gram showing that Prussian Blue has promise as an electrode material for applications needing high rates of charge-discharge.

  15. Distributed Storage Allocation Problems

    OpenAIRE

    Leong, Derek; Dimakis, Alexandros G.; Ho, Tracey

    2009-01-01

    We investigate the problem of using several storage nodes to store a data object, subject to an aggregate storage budget or redundancy constraint. It is challenging to find the optimal allocation that maximizes the probability of successful recovery by the data collector because of the large space of possible symmetric and nonsymmetric allocations, and the nonconvexity of the problem. For the special case of probability-l recovery, we show that the optimal allocatio...

  16. Design and evaluation of a microgrid for PEV charging with flexible distribution of energy sources and storage

    Science.gov (United States)

    Pyne, Moinak

    This thesis aspires to model and control, the flow of power in a DC microgrid. Specifically, the energy sources are a photovoltaic system and the utility grid, a lead acid battery based energy storage system and twenty PEV charging stations as the loads. Theoretical principles of large scale state space modeling are applied to model the considerable number of power electronic converters needed for controlling voltage and current thresholds. The energy storage system is developed using principles of neural networks to facilitate a stable and uncomplicated model of the lead acid battery. Power flow control is structured as a hierarchical problem with multiple interactions between individual components of the microgrid. The implementation is done using fuzzy logic with scheduling the maximum use of available solar energy and compensating demand or excess power with the energy storage system, and minimizing utility grid use, while providing multiple speeds of charging the PEVs.

  17. Flywheel energy storage workshop

    Energy Technology Data Exchange (ETDEWEB)

    O`Kain, D.; Carmack, J. [comps.

    1995-12-31

    Since the November 1993 Flywheel Workshop, there has been a major surge of interest in Flywheel Energy Storage. Numerous flywheel programs have been funded by the Advanced Research Projects Agency (ARPA), by the Department of Energy (DOE) through the Hybrid Vehicle Program, and by private investment. Several new prototype systems have been built and are being tested. The operational performance characteristics of flywheel energy storage are being recognized as attractive for a number of potential applications. Programs are underway to develop flywheels for cars, buses, boats, trains, satellites, and for electric utility applications such as power quality, uninterruptible power supplies, and load leveling. With the tremendous amount of flywheel activity during the last two years, this workshop should again provide an excellent opportunity for presentation of new information. This workshop is jointly sponsored by ARPA and DOE to provide a review of the status of current flywheel programs and to provide a forum for presentation of new flywheel technology. Technology areas of interest include flywheel applications, flywheel systems, design, materials, fabrication, assembly, safety & containment, ball bearings, magnetic bearings, motor/generators, power electronics, mounting systems, test procedures, and systems integration. Information from the workshop will help guide ARPA & DOE planning for future flywheel programs. This document is comprised of detailed viewgraphs.

  18. Optimal DG Source Allocation for Grid Connected Distributed Generation with Energy Storage System

    Directory of Open Access Journals (Sweden)

    S. Ezhilarasan

    2015-05-01

    Full Text Available This study proposes an Energy Management System (EMS for allocation of DG source in a grid connected hybrid power system. Modeling and simulation for EMS is implemented using MATLAB/SIMULINK package. The objective of proposed EMS for micro grid is to optimize the fuel cost, improving the energy utilization efficiency and to manage the peak load demand by scheduling the generation according to the availability of the fuel. The proposed intelligent energy management system is designed to optimize the availability of energy to the load according to the level of priority and to manage the power flow. The developed management system performance was assessed using a hybrid system having PV panels, Wind Turbine (WT, battery and biomass gasifier. Real time field test has been conducted and the parameters i.e., solar irradiance, temperature, wind speed are gathered from 4.05 KW off grid and 2.0 KW On grid Solar Photovoltaic systems (SPV system and wind turbine. The dynamic behavior of the proposed model is examined under different operating conditions. The simulation results of proposed EMS using fuzzy logic expert system shows the minimization on the operating cost and emission level of micro grid by optimal scheduling of power generation and maintains the State of Charge (SOC of batteries in desired value which improves the battery life. The proposed multi objective intelligent energy management system aims to minimize the operational cost and the environmental impact of a micro grid.

  19. Solar energy storage

    CERN Document Server

    Sorensen, Bent

    2015-01-01

    While solar is the fastest-growing energy source in the world, key concerns around solar power's inherent variability threaten to de-rail that scale-up . Currently, integration of intermittent solar resources into the grid creates added complication to load management, leading some utilities to reject it altogether, while other operators may penalize the producers via rate increases or force solar developers to include storage devices on-site to smooth out power delivery at the point of production. However these efforts at mitigation unfold, it is increasingly clear to parties on all sides th

  20. Energy Storage System

    Science.gov (United States)

    1996-01-01

    SatCon Technology Corporation developed the drive train for use in the Chrysler Corporation's Patriot Mark II, which includes the Flywheel Energy Storage (FES) system. In Chrysler's experimental hybrid- electric car, the hybrid drive train uses an advanced turboalternator that generates electricity by burning a fuel; a powerful, compact electric motor; and a FES that eliminates the need for conventional batteries. The FES system incorporates technology SatCon developed in more than 30 projects with seven NASA centers, mostly for FES systems for spacecraft attitude control and momentum recovery. SatCon will continue to develop the technology with Westinghouse Electric Corporation.

  1. Cooperative Operation of Battery Energy Storage System and Dispatchable Distributed Generations in Microgrid System

    DEFF Research Database (Denmark)

    Zhao, Haoran; Cha, Seung-Tae; Rasmussen, Claus Nygaard

    Microgrid is an efficient solution to the utilization of renewable energy. According to the different operations (grid-connected or islanded), a fuzzy-logic based control strategy between BESS and dispatchable DG units is proposed in this paper, where the BESS plays a key role. The effectiveness...

  2. 分布式风储系统设计%Design of Distributed Wind Turbine-Energy Storage System

    Institute of Scientific and Technical Information of China (English)

    梁嘉; 张敏吉; 孙洋洲; 李硕; 凌志斌

    2014-01-01

    风储配合解决新能源并网的有效途径之一。针对中海油化德风电场,在分析比较各种风储配置方式的基础上,采用一机一储的分布式风储系统配置,介绍了风储系统的结构、采用的控制运行模式及控制策略、采样控制点位置和通讯方式,为相关的储能研究、设计和应用推广提供了参考。%Battery energy storage system is an efficient means for renewable energy integration. In the design of CNOOC Huade wind farm,the pattern of one storage system for one wind turbine is adopted based on the analysis and comparison of various wind energy storage configurations. This paper introduces the structure,control mode and control strategy used, sampling control positions and the communication mode of the wind energy storage system,and it can provide useful reference for the relevant energy storage research,design,application and promotion.

  3. Distributed Cooperative Control of Multi Flywheel Energy Storage System for Electrical Vehicle Fast Charging Stations

    DEFF Research Database (Denmark)

    Sun, Bo; Dragicevic, Tomislav; Quintero, Juan Carlos Vasquez

    2015-01-01

    Plug-in electrical vehicles will play a critical role in future smart grid and sudden connection of electrical vehicles chargers may cause huge power-peaks with high slew-rates on grid. In order to cope with this issue, this paper applies a distributed cooperative control for fast charging station...... consensus based voltage observer by communicating with its neighbors. The control system can realize the power balancing and DC voltage regulation with low reliance on communications. Finally, real-time hardware-in-the-loop results have been reported in order to verify the feasibility of proposed approach....

  4. Battery energy storage system

    NARCIS (Netherlands)

    Tol, C.S.P.; Evenblij, B.H.

    2009-01-01

    The ability to store electrical energy adds several interesting features to a ships distribution network, as silent power, peak shaving and a ride through in case of generator failure. Modern intrinsically safe Li-ion batteries bring these within reach. For this modern lithium battery applications t

  5. Battery energy storage system

    NARCIS (Netherlands)

    Tol, C.S.P.; Evenblij, B.H.

    2009-01-01

    The ability to store electrical energy adds several interesting features to a ships distribution network, as silent power, peak shaving and a ride through in case of generator failure. Modern intrinsically safe Li-ion batteries bring these within reach. For this modern lithium battery applications t

  6. Battery energy storage system

    NARCIS (Netherlands)

    Tol, C.S.P.; Evenblij, B.H.

    2009-01-01

    The ability to store electrical energy adds several interesting features to a ships distribution network, as silent power, peak shaving and a ride through in case of generator failure. Modern intrinsically safe Li-ion batteries bring these within reach. For this modern lithium battery applications

  7. Terrestrial Energy Storage SPS Systems

    Science.gov (United States)

    Brandhorst, Henry W., Jr.

    1998-01-01

    Terrestrial energy storage systems for the SSP system were evaluated that could maintain the 1.2 GW power level during periods of brief outages from the solar powered satellite (SPS). Short-term outages of ten minutes and long-term outages up to four hours have been identified as "typical" cases where the ground-based energy storage system would be required to supply power to the grid. These brief interruptions in transmission could result from performing maintenance on the solar power satellite or from safety considerations necessitating the power beam be turned off. For example, one situation would be to allow for the safe passage of airplanes through the space occupied by the beam. Under these conditions, the energy storage system needs to be capable of storing 200 MW-hrs and 4.8 GW-hrs, respectively. The types of energy storage systems to be considered include compressed air energy storage, inertial energy storage, electrochemical energy storage, superconducting magnetic energy storage, and pumped hydro energy storage. For each of these technologies, the state-of-the-art in terms of energy and power densities were identified as well as the potential for scaling to the size systems required by the SSP system. Other issues addressed included the performance, life expectancy, cost, and necessary infrastructure and site locations for the various storage technologies.

  8. Advanced materials for energy storage.

    Science.gov (United States)

    Liu, Chang; Li, Feng; Ma, Lai-Peng; Cheng, Hui-Ming

    2010-02-23

    Popularization of portable electronics and electric vehicles worldwide stimulates the development of energy storage devices, such as batteries and supercapacitors, toward higher power density and energy density, which significantly depends upon the advancement of new materials used in these devices. Moreover, energy storage materials play a key role in efficient, clean, and versatile use of energy, and are crucial for the exploitation of renewable energy. Therefore, energy storage materials cover a wide range of materials and have been receiving intensive attention from research and development to industrialization. In this Review, firstly a general introduction is given to several typical energy storage systems, including thermal, mechanical, electromagnetic, hydrogen, and electrochemical energy storage. Then the current status of high-performance hydrogen storage materials for on-board applications and electrochemical energy storage materials for lithium-ion batteries and supercapacitors is introduced in detail. The strategies for developing these advanced energy storage materials, including nanostructuring, nano-/microcombination, hybridization, pore-structure control, configuration design, surface modification, and composition optimization, are discussed. Finally, the future trends and prospects in the development of advanced energy storage materials are highlighted.

  9. A Framework for Evaluating Economic Impacts of Rooftop PV Systems with or without Energy Storage on Thai Distribution Utilities and Ratepayers

    Science.gov (United States)

    Chaianong, A.; Bangviwat, A.; Menke, C.

    2017-07-01

    Driven by decreasing PV and energy storage prices, increasing electricity costs and policy supports from Thai government (self-consumption era), rooftop PV and energy storage systems are going to be deployed in the country rapidly that may disrupt existing business models structure of Thai distribution utilities due to revenue erosion and lost earnings opportunities. The retail rates that directly affect ratepayers (non-solar customers) are expected to increase. This paper focuses on a framework for evaluating impacts of PV with and without energy storage systems on Thai distribution utilities and ratepayers by using cost-benefit analysis (CBA). Prior to calculation of cost/benefit components, changes in energy sales need to be addressed. Government policies for the support of PV generation will also help in accelerating the rooftop PV installation. Benefit components include avoided costs due to transmission losses and deferring distribution capacity with appropriate PV penetration level, while cost components consist of losses in revenue, program costs, integration costs and unrecovered fixed costs. It is necessary for Thailand to compare total costs and total benefits of rooftop PV and energy storage systems in order to adopt policy supports and mitigation approaches, such as business model innovation and regulatory reform, effectively.

  10. Superconducting energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Giese, R.F.

    1993-10-01

    This report describes the status of energy storage involving superconductors and assesses what impact the recently discovered ceramic superconductors may have on the design of these devices. Our description is intended for R&D managers in government, electric utilities, firms, and national laboratories who wish an overview of what has been done and what remains to be done. It is assumed that the reader is acquainted with superconductivity, but not an expert on the topics discussed here. Indeed, it is the author`s aim to enable the reader to better understand the experts who may ask for the reader`s attention, support, or funding. This report may also inform scientists and engineers who, though expert in related areas, wish to have an introduction to our topic.

  11. Energy storage for electrical systems in the USA

    Directory of Open Access Journals (Sweden)

    Eugene Freeman

    2016-10-01

    Full Text Available Energy storage is becoming increasingly important as renewable generation sources such as Wind Turbine and Photo Voltaic Solar are added to the mix in electrical power generation and distribution systems. The paper discusses the basic drivers for energy storage and provides brief descriptions of the various energy storage technologies available. The information summarizes current technical tradeoffs with different storage approaches and identifies issues surrounding deployment of large scale energy storage systems.

  12. Energy Storage and Smart Energy Systems

    DEFF Research Database (Denmark)

    Lund, Henrik; Østergaard, Poul Alberg; Connolly, David

    2016-01-01

    It is often highlighted how the transition to renewable energy supply calls for significant electricity storage. However, one has to move beyond the electricity-only focus and take a holistic energy system view to identify optimal solutions for integrating renewable energy. In this paper......, an integrated cross-sector approach is used to determine the most efficient and least-cost storage options for the entire renewable energy system concluding that the best storage solutions cannot be found through analyses focusing on the individual sub-sectors. Electricity storage is not the optimum solution...... to integrate large inflows of fluctuating renewable energy, since more efficient and cheaper options can be found by integrating the electricity sector with other parts of the energy system and by this creating a Smart Energy System. Nevertheless, this does not imply that electricity storage should...

  13. Energy Storage and Smart Energy Systems

    DEFF Research Database (Denmark)

    Lund, Henrik; Østergaard, Poul Alberg; Connolly, David

    2016-01-01

    It is often highlighted how the transition to renewable energy supply calls for significant electricity storage. However, one has to move beyond the electricity-only focus and take a holistic energy system view to identify optimal solutions for integrating renewable energy. In this paper......, an integrated cross-sector approach is used to determine the most efficient and least-cost storage options for the entire renewable energy system concluding that the best storage solutions cannot be found through analyses focusing on the individual sub-sectors. Electricity storage is not the optimum solution...... to integrate large inflows of fluctuating renewable energy, since more efficient and cheaper options can be found by integrating the electricity sector with other parts of the energy system and by this creating a Smart Energy System. Nevertheless, this does not imply that electricity storage should...

  14. NV Energy Electricity Storage Valuation

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, James F.; Bhatnagar, Dhruv; Samaan, Nader A.; Jin, Chunlian

    2013-06-30

    This study examines how grid-level electricity storage may benet the operations of NV Energy in 2020, and assesses whether those benets justify the cost of the storage system. In order to determine how grid-level storage might impact NV Energy, an hourly production cost model of the Nevada Balancing Authority (\\BA") as projected for 2020 was built and used for the study. Storage facilities were found to add value primarily by providing reserve. Value provided by the provision of time-of-day shifting was found to be limited. If regulating reserve from storage is valued the same as that from slower ramp rate resources, then it appears that a reciprocating engine generator could provide additional capacity at a lower cost than a pumped storage hydro plant or large storage capacity battery system. In addition, a 25-MW battery storage facility would need to cost $650/kW or less in order to produce a positive Net Present Value (NPV). However, if regulating reserve provided by storage is considered to be more useful to the grid than that from slower ramp rate resources, then a grid-level storage facility may have a positive NPV even at today's storage system capital costs. The value of having storage provide services beyond reserve and time-of-day shifting was not assessed in this study, and was therefore not included in storage cost-benefit calculations.

  15. Energy storage systems: power grid and energy market use cases

    Directory of Open Access Journals (Sweden)

    Komarnicki Przemysław

    2016-09-01

    Full Text Available Current power grid and market development, characterized by large growth of distributed energy sources in recent years, especially in Europa, are according energy storage systems an increasingly larger field of implementation. Existing storage technologies, e.g. pumped-storage power plants, have to be upgraded and extended by new but not yet commercially viable technologies (e.g. batteries or adiabatic compressed air energy storage that meet expected demands. Optimal sizing of storage systems and technically and economically optimal operating strategies are the major challenges to the integration of such systems in the future smart grid. This paper surveys firstly the literature on the latest niche applications. Then, potential new use case and operating scenarios for energy storage systems in smart grids, which have been field tested, are presented and discussed and subsequently assessed technically and economically.

  16. Controlled storage for distributed power generation and optimised energy flow in low-voltage mains; Steuerbare Speicher zur Optimierung des Energieflusses in Niederspannungsnetzen mit DEA

    Energy Technology Data Exchange (ETDEWEB)

    Hoeckel, M.; Vollenwyder, R. [Berner Fachhochschule, Hochschule fuer Technik und Informatik (BFH-HTI), Biel (Switzerland); Buholzer, M.; Kreyenbuehl, U. [RIPEnergy AG, Zollikon (Switzerland); Schnyder, G.; Mauchle, P. [Schnyder Ingenieure AG, Huenenberg (Switzerland)

    2005-07-01

    This comprehensive final report for the Swiss Federal Office of Energy (SFOE) examines ways to optimise energy flows in mains networks that include distributed generation facilities. Increasing use of decentralised generation, its effects on the operation of low-voltage mains and the efficient use of the 400 V mains is discussed. The principles of operation and construction of controlled storage installations are discussed and concrete examples of their use in both grid-connected and island operation are quoted. Alternatives to storage are looked at from both the technical and economic points of view. The storage technologies used such as flywheels, supercaps, redox-flow batteries and lead-acid accumulators are briefly assessed and the results of simulations are discussed.

  17. Energy Storage Criteria Handbook.

    Science.gov (United States)

    1982-10-01

    using latent heat storage , as are the more elaborate simulation methods such as TRNSYS . I 0 S 168 7.6 Symbols Used Main Symbols Cp heat capacity in Btu... Storage Purpose Review chapter 7, read section 14.1.1, and for more precise calcula- tions, refer to DOE-I or TRNSYS . A simpler method of analyzing...with sensible heat storage . An analysis method such as TRNSYS , DOE-I or f-Chart would be used to estimate the system performance. System performance

  18. Energy storage for power systems

    CERN Document Server

    Ter-Gazarian, Andrei

    2011-01-01

    The supply of energy from primary sources is not constant and rarely matches the pattern of demand from consumers. Electricity is also difficult to store in significant quantities. Therefore, secondary storage of energy is essential to increase generation capacity efficiency and to allow more substantial use of renewable energy sources that only provide energy intermittently. Lack of effective storage has often been cited as a major hurdle to substantial introduction of renewable energy sources into the electricity supply network.This 2nd edition, without changing the existing structure of the

  19. Storage to Energy Calculator

    NARCIS (Netherlands)

    Taal, A.; Makkes, M.X.; Grosso, P.

    2014-01-01

    Computational and storage tasks can nowadays be offloaded among data centers, in order to optimize costs and or performance. We set out to investigate what are the environmental effects, namely the total CO2 emission, of such offloading. We built models for the various components present in these of

  20. Hydrogen Storage Technologies for Future Energy Systems.

    Science.gov (United States)

    Preuster, Patrick; Alekseev, Alexander; Wasserscheid, Peter

    2017-06-07

    Future energy systems will be determined by the increasing relevance of solar and wind energy. Crude oil and gas prices are expected to increase in the long run, and penalties for CO2 emissions will become a relevant economic factor. Solar- and wind-powered electricity will become significantly cheaper, such that hydrogen produced from electrolysis will be competitively priced against hydrogen manufactured from natural gas. However, to handle the unsteadiness of system input from fluctuating energy sources, energy storage technologies that cover the full scale of power (in megawatts) and energy storage amounts (in megawatt hours) are required. Hydrogen, in particular, is a promising secondary energy vector for storing, transporting, and distributing large and very large amounts of energy at the gigawatt-hour and terawatt-hour scales. However, we also discuss energy storage at the 120-200-kWh scale, for example, for onboard hydrogen storage in fuel cell vehicles using compressed hydrogen storage. This article focuses on the characteristics and development potential of hydrogen storage technologies in light of such a changing energy system and its related challenges. Technological factors that influence the dynamics, flexibility, and operating costs of unsteady operation are therefore highlighted in particular. Moreover, the potential for using renewable hydrogen in the mobility sector, industrial production, and the heat market is discussed, as this potential may determine to a significant extent the future economic value of hydrogen storage technology as it applies to other industries. This evaluation elucidates known and well-established options for hydrogen storage and may guide the development and direction of newer, less developed technologies.

  1. `Energy storage` using liquid air

    Energy Technology Data Exchange (ETDEWEB)

    Brown, K.C. [Melbourne Univ., Parkville, VIC (Australia)

    1995-12-31

    Storage of liquid air is relatively simple, and the work needed to manufacture it is, at least in principle, entirely recoverable. Available energy densities seem excellent. Unfortunately the technology to use liquid air for energy storage has never been developed. The Phillips-Stirling and McMahon and Gifford air liquefiers, and a previous proposal by Smith, provide leads as to the form which the technology might take. This paper introduces the concept of `Exergy`, and how it can be utilized in the storage of liquid air. It concludes that liquid air seems to present some real advantages over batteries for energy storage. The development presents a challenge. Since battery technology is not making the huge advances promised, it could be time to take a more serious look at this alternative. (author). 4 figs., 14 refs.

  2. Energy storage for sustainable microgrid

    CERN Document Server

    Gao, David Wenzhong

    2015-01-01

    Energy Storage for Sustainable Microgrid addresses the issues related to modelling, operation and control, steady-state and dynamic analysis of microgrids with ESS. This book discusses major electricity storage technologies in depth along with their efficiency, lifetime cycles, environmental benefits and capacity, so that readers can envisage which type of storage technology is best for a particular microgrid application. This book offers solutions to numerous difficulties such as choosing the right ESS for the particular microgrid application, proper sizing of ESS for microgrid, as well as

  3. Energy storage-boiler tank

    Science.gov (United States)

    Chubb, T. A.; Nemecek, J. J.; Simmons, D. E.

    1980-01-01

    Activities performed in an effort to demonstrate heat of fusion energy storage in containerized salts are reported. The properties and cycle life characteristics of a eutectic salt having a boiling point of about 385 C (NaCl, KCl, Mg Cl2) were determined. M-terphenyl was chosen as the heat transfer fluid. Compatibility studies were conducted and mild steel containers were selected. The design and fabrication of a 2MWh storage boiler tank are discussed.

  4. Thermal energy storage test facility

    Science.gov (United States)

    Ternes, M. P.

    1980-01-01

    The thermal behavior of prototype thermal energy storage units (TES) in both heating and cooling modes is determined. Improved and advanced storage systems are developed and performance standards are proposed. The design and construction of a thermal cycling facility for determining the thermal behavior of full scale TES units is described. The facility has the capability for testing with both liquid and air heat transport, at variable heat input/extraction rates, over a temperature range of 0 to 280 F.

  5. Underground thermal energy storage

    CERN Document Server

    Lee, Kun Sang

    2014-01-01

    Summarizing several decades of development in UTES-strategically vital in combating global warming-this book, which includes current statistics and real-world applications, forms an excellent introduction to this widely used method of energy conservation.

  6. Microencapsulated PCM thermal-energy storage system

    Energy Technology Data Exchange (ETDEWEB)

    Hawlader, M.N.A.; Uddin, M.S. [National Univ. of Singapore, Dept. of Chemical and Environmental Engineering, Singapore (Singapore); Khin, Mya Mya [National Univ. of Singapore, Dept. of Mechanical Engineering, Singapore (Singapore)

    2003-02-01

    The application of phase-change materials (PCM) for solar thermal-energy storage capacities has received considerable attention in recent years due to their large storage capacity and isothermal nature of the storage process. This study deals with the preparation and characterization of encapsulated paraffin-wax. Encapsulated paraffin particles were prepared by complex coacervation as well as spray-drying methods. The influence of different parameters on the characteristics and performance of a microencapsulated PCM in terms of encapsulation efficiency, and energy storage and release capacity has been investigated. The distribution of particle size and the morphology of microencapsulated PCM were analyzed by a scanning electron microscope (SEM). In the coacervation method, the optimum homogenizing time is 10 min and the amount of cross-linking agent is 6-8 mI. Results obtained from a differential scanning calorimeter (DSC) show that microcapsules prepared either by coacervation or the spray-drying method have a thermal energy storage/release capacity of about 145-240 J/g. Hence, encapsulated paraffin wax shows a good potential as a solar-energy storage material. (Author)

  7. 基于存储结构重配置的分布式存储系统节能算法%Energy-Efficient Algorithms for Distributed Storage System Based on Data Storage Structure Reconfiguration

    Institute of Scientific and Technical Information of China (English)

    廖彬; 于炯; 孙华; 年梅

    2013-01-01

    As an underlying core infrastructure and important component of cloud computing, distributed storage system is the foundation of all kinds of cloud services or applications. However, with the expanding of system scale and energy consumption factors being ignored by its designers, the problem of high energy consumption is exposed. Because of data availability requirements, we cannot simply use the existing energy-saving technologies to solve the distributed storage system's high energy consumption problem. To ensure all data's availability is the premise of designing energy efficient algorithms for distributed storage system. In this paper, we create a system and data availability model After studying the storage structure and mechanism, the relationship between server's status and data's availability, the method to solve the problem of full covering by constructing a data's availability measurement matrix is proposed. The energy saving model for distributed storage system is defined. The RACK is divided into Active-Zone and Sleep-Zone distinct storage area. According to the different data access frequency and regularity, we calculate the different activity factors for different data which decide how many replicas are stored in Active-Zone. The servers in Sleep Zone are turn to sleep for energy saving while the work load of data center is low. Experimental results show that, the energy-efficient algorithms in this paper adapt the access rule and the availability of all the data in system, improve the energy-efficient of distributed storage system, and the algorithm is more efficient when the system's work load and average activity factor is low.%作为云计算底层核心基础设施,分布式数据存储系统是各种云计算服务的基础,是云计算重要的组成部分.然而随着系统规模的不断扩大以及设计时对能耗因素的忽略使其暴露出高能耗问题.由于存在数据可用性要求,使其并不能简单采用已有节能技术

  8. Energy storage in evaporated brine

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, R. Ian

    2010-09-15

    We propose storage of electrical energy in brine solutions by using the energy to enhance natural evaporation. Using properties of existing industrial evaporation technologies and estimates of power regeneration from brine by pressure retarded osmosis, efficiency near 100% is calculated. Modelling indicates that systems ranging from 50kW to 50MW output may be practical, with storage capacities of hours to days. The method appears to have potential to be economically competitive with other technologies over a wide range of capacity. It may present a large new application area that could aid the development of salinity-based power generation technology.

  9. 分布式发电系统中储能单元的容量优化%Capacity optimization of energy storage units in distributed generation system

    Institute of Scientific and Technical Information of China (English)

    王西伟; 熊炜; 刘君; 韩士博; 袁旭峰

    2013-01-01

    为了解决分布式发电系统中储能单元的容量优化问题,利用超级电容器储能与蓄电池储能的互补特性,将二者综合考虑,以最小成本为优化目标函数,系统性能指标为约束条件,应用混沌蚁群算法,进行容量的组合优化设计.结果表明,该方法是有效的.%In order to solve the problems of optimum size of energy storage capacity for distributed generation system,combinatorial optimization of ultracapacitor and battery's capacity using chaos ant colony algorithm was studied.The object was to minimize the initial investment of the storage section, with performance indices as constrained. The result shows that this approach is valid.

  10. Energy Conversion and Storage Program

    Energy Technology Data Exchange (ETDEWEB)

    Cairns, E.J.

    1992-03-01

    The Energy Conversion and Storage Program applies chemistry and materials science principles to solve problems in (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes, and (5) application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis. Electrochemistry research aims to develop advanced power systems for electric vehicle and stationary energy storage applications. Topics include identification of new electrochemical couples for advanced rechargeable batteries, improvements in battery and fuel-cell materials, and the establishment of engineering principles applicable to electrochemical energy storage and conversion. Chemical Applications research includes topics such as separations, catalysis, fuels, and chemical analyses. Included in this program area are projects to develop improved, energy-efficient methods for processing waste streams from synfuel plants and coal gasifiers. Other research projects seek to identify and characterize the constituents of liquid fuel-system streams and to devise energy-efficient means for their separation. Materials Applications research includes the evaluation of the properties of advanced materials, as well as the development of novel preparation techniques. For example, the use of advanced techniques, such as sputtering and laser ablation, are being used to produce high-temperature superconducting films.

  11. Multifunctional composites for energy storage

    Science.gov (United States)

    Shuvo, Mohammad Arif I.; Karim, Hasanul; Rajib, Md; Delfin, Diego; Lin, Yirong

    2014-03-01

    Electrochemical super-capacitors have become one of the most important topics in both academia and industry as novel energy storage devices because of their high power density, long life cycles, and high charge/discharge efficiency. Recently, there has been an increasing interest in the development of multifunctional structural energy storage devices such as structural super-capacitors for applications in aerospace, automobiles and portable electronics. These multifunctional structural super-capacitors provide lighter structures combining energy storage and load bearing functionalities. Due to their superior materials properties, carbon fiber composites have been widely used in structural applications for aerospace and automotive industries. Besides, carbon fiber has good electrical conductivity which will provide lower equivalent series resistance; therefore, it can be an excellent candidate for structural energy storage applications. Hence, this paper is focused on performing a pilot study for using nanowire/carbon fiber hybrids as building materials for structural energy storage materials; aiming at enhancing the charge/discharge rate and energy density. This hybrid material combines the high specific surface area of carbon fiber and pseudo-capacitive effect of metal oxide nanowires which were grown hydrothermally in an aligned fashion on carbon fibers. The aligned nanowire array could provide a higher specific surface area that leads to high electrode-electrolyte contact area and fast ion diffusion rates. Scanning Electron Microscopy (SEM) and XRay Diffraction (XRD) measurements were used for the initial characterization of this nanowire/carbon fiber hybrid material system. Electrochemical testing has been performed using a potentio-galvanostat. The results show that gold sputtered nanowire hybrid carbon fiber provides 65.9% better performance than bare carbon fiber cloth as super-capacitor.

  12. Energy storage systems impact on the short-term frequency stability of distributed autonomous microgrids, an analysis using aggregate models

    DEFF Research Database (Denmark)

    Serban, Ioan; Teodorescu, Remus; Marinescu, Corneliu

    2013-01-01

    is on autonomous MGs that dynamically behave similarly to the classical power systems. This is the systems case with classical distributed generators (DGs), but which can also contain renewable energy sources (RESs) in a certain penetration level. During MG islanded operation, the local generators take over most...... with both inertial response and an adaptive droop characteristic during battery state-of-charge limitations. The conducted analysis is accomplished by adopting aggregated models for the involved control mechanisms. The developed model is analysed in frequency domain, whereas an experimental test bench...

  13. Combined solar collector and energy storage system

    Science.gov (United States)

    Jensen, R. N. (Inventor)

    1980-01-01

    A combined solar energy collector, fluid chiller and energy storage system is disclosed. A movable interior insulated panel in a storage tank is positionable flush against the storage tank wall to insulate the tank for energy storage. The movable interior insulated panel is alternately positionable to form a solar collector or fluid chiller through which the fluid flows by natural circulation.

  14. Nanoconfined hydrides for energy storage

    Science.gov (United States)

    Nielsen, Thomas K.; Besenbacher, Flemming; Jensen, Torben R.

    2011-05-01

    The world in the 21st century is facing increasing challenges within the development of more environmentally friendly energy systems, sustainable and `green chemistry' solutions for a variety of chemical and catalytic processes. Nanomaterials science is expected to contribute strongly by the development of new nanotools, e.g. for improving the performance of chemical reactions. Nanoconfinement is of increasing interest and may lead to significantly enhanced kinetics, higher degree of stability and/or more favourable thermodynamic properties. Nanoconfined chemical reactions may have a wide range of important applications in the near future, e.g. within the merging area of chemical storage of renewable energy. This review provides selected examples within nanoconfinement of hydrogen storage materials, which may serve as an inspiration for other research fields as well. Selected nanoporous materials, methods for preparation of nanoconfined systems and their hydrogen storage properties are reviewed.The world in the 21st century is facing increasing challenges within the development of more environmentally friendly energy systems, sustainable and `green chemistry' solutions for a variety of chemical and catalytic processes. Nanomaterials science is expected to contribute strongly by the development of new nanotools, e.g. for improving the performance of chemical reactions. Nanoconfinement is of increasing interest and may lead to significantly enhanced kinetics, higher degree of stability and/or more favourable thermodynamic properties. Nanoconfined chemical reactions may have a wide range of important applications in the near future, e.g. within the merging area of chemical storage of renewable energy. This review provides selected examples within nanoconfinement of hydrogen storage materials, which may serve as an inspiration for other research fields as well. Selected nanoporous materials, methods for preparation of nanoconfined systems and their hydrogen storage

  15. Thermal energy storage testing facility

    Science.gov (United States)

    Schoenhals, R. J.; Lin, C. P.; Kuehlert, H. F.; Anderson, S. H.

    1981-03-01

    Development of a prototype testing facility for performance evaluation of electrically heated thermal energy storage units is described. Laboratory apparatus and test procedures were evaluated by means of measurements and analysis. A 30kW central unit and several smaller individual room-size units were tested.

  16. Thermal energy storage testing facilities

    Science.gov (United States)

    Schoenhals, R. J.; Anderson, S. H.; Stevens, L. W.; Laster, W. R.; Elter, M. R.

    Development of a prototype testing facility for performance evaluation of electrically heated thermal energy storage units is discussed. Laboratory apparatus and test procedures are being evaluated by means of measurements and analysis. Testing procedures were improved, and test results were acquired for commercially available units. A 30 kW central unit and several smaller individual room-size units were tested.

  17. Energy aspects of food storage

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R. (Bari Univ. (Italy). Ist. di Fisica Tecnica)

    1989-08-01

    In all industrial countries, the refrigeration industry is steadily occupying a place of greater importance because of the value of machines and equipment produced, as well as the products being treated and the energy used. Refrigeration is one of the many food storage techniques. Contrary to what we may think, this technique is the most expensive from the energy point of view, if all energy costs involved are taken into consideration. In industrial refrigeration plants, the measures for energy saving can be very effective, above all, if - at the design level - not only the initial costs have been correctly allocated, but also the operational costs.

  18. 峰谷电价下配电网中分布式储能的容量配置%Capacity Configuration of Distribution Energy Storage in Distribution Network Under the Peak-valley Price

    Institute of Scientific and Technical Information of China (English)

    杨江涛; 孙春顺; 杨安; 刘佳

    2016-01-01

    为了进一步提高电力系统的可靠性和经济性,对配电网中储能设备的容量进行合理配置。基于分布式储能装置的引入给配电系统带来的影响,并考虑峰谷电价政策的影响,针对储能装置带来的经济效益分别从发电侧、输配电过程、降低网损、峰谷电价效益等各方面进行了经济性上的量化;结合储能装置的自身成本,以年收益最大为目标建立了储能装置容量的优化配置模型。最后考虑储能装置给系统潮流带来的影响,在约束条件中加入节点电压波动约束,通过对算例进行分析,得到了不同类型储能设备的最优容量配置。%In order to improve the reliability and economy of power system further, the capacity of energy storage device should be allocated with ration in the power distribution network. This paper analyzes the effect of the energy storage device on the power distribution system. On this basis, taking the influence of the peak valley price policy on the system into consideration, the benefits of the energy storage device to the system are analyzed, from the as-pects of the power generation, transmission and distribution process, network loss reduce, peak valley price benefit and so on, and are quantified on the side of economy. Combined with the costs of the energy storage device, with the goal of maximizing the revenue, an optimal allocation model of energy storage device capacity is established. Finally, considering the effects of energy storage device to the system trend and adding node voltage fluctuation in constraint conditions, the optimal capacity configurations of different types of energy storage devices are obtained by the analysis of the proposed example.

  19. Thermal energy storage devices, systems, and thermal energy storage device monitoring methods

    Science.gov (United States)

    Tugurlan, Maria; Tuffner, Francis K; Chassin, David P.

    2016-09-13

    Thermal energy storage devices, systems, and thermal energy storage device monitoring methods are described. According to one aspect, a thermal energy storage device includes a reservoir configured to hold a thermal energy storage medium, a temperature control system configured to adjust a temperature of the thermal energy storage medium, and a state observation system configured to provide information regarding an energy state of the thermal energy storage device at a plurality of different moments in time.

  20. Energy Storage Flywheels on Spacecraft

    Science.gov (United States)

    Bartlett, Robert O.; Brown, Gary; Levinthal, Joel; Brodeur, Stephen (Technical Monitor)

    2002-01-01

    With advances in carbon composite material, magnetic bearings, microprocessors, and high-speed power switching devices, work has begun on a space qualifiable Energy Momentum Wheel (EMW). An EMW is a device that can be used on a satellite to store energy, like a chemical battery, and manage angular momentum, like a reaction wheel. These combined functions are achieved by the simultaneous and balanced operation of two or more energy storage flywheels. An energy storage flywheel typically consists of a carbon composite rotor driven by a brushless DC motor/generator. Each rotor has a relatively large angular moment of inertia and is suspended on magnetic bearings to minimize energy loss. The use of flywheel batteries on spacecraft will increase system efficiencies (mass and power), while reducing design-production time and life-cycle cost. This paper will present a discussion of flywheel battery design considerations and a simulation of spacecraft system performance utilizing four flywheel batteries to combine energy storage and momentum management for a typical LEO satellite. A proposed set of control laws and an engineering animation will also be presented. Once flight qualified and demonstrated, space flywheel batteries may alter the architecture of most medium and high-powered spacecraft.

  1. Nuclear Hybrid energy Systems: Molten Salt Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Green, M.; Sabharwall, P.; Yoon, S. J.; Bragg-Sitton, S. B.; Stoot, C.

    2014-07-01

    Without growing concerns in reliable energy supply, the next generation in reliable power generation via hybrid energy systems is being developed. A hybrid energy system incorporates multiple energy input source sand multiple energy outputs. The vitality and efficiency of these combined systems resides in the energy storage application. Energy storage is necessary for grid stabilization because stored excess energy is used later to meet peak energy demands. With high thermal energy production the primary nuclear heat generation source, molten salt energy storage is an intriguing option because of its distinct thermal properties. This paper discusses the criteria for efficient energy storage and molten salt energy storage system options for hybrid systems. (Author)

  2. Energy Wastage Estimation of a Cold Storage

    Directory of Open Access Journals (Sweden)

    Dr. N. Mukhopadhyay

    2015-12-01

    Full Text Available Energy consumption of a cold storage was measured for different storage temperatures. Suction temperature and pressure temperature of the compressor and working time of the compressor were determined to reach evaporator setup temperatures. An axial fan located back of the evaporator was used to distribute the cooled air into the cold store. An electrical heater was used to defrost. The compressor suction temperature of ammonia vapour variedbetween273K–271Kand 305K–308K respectively. Compressor suction pressure(p1=3.5 Kg/cm 2 and discharge pressure (p2=10.5Kg/cm 2

  3. Modeling and experimental performance of an intermediate temperature reversible solid oxide cell for high-efficiency, distributed-scale electrical energy storage

    Science.gov (United States)

    Wendel, Christopher H.; Gao, Zhan; Barnett, Scott A.; Braun, Robert J.

    2015-06-01

    Electrical energy storage is expected to be a critical component of the future world energy system, performing load-leveling operations to enable increased penetration of renewable and distributed generation. Reversible solid oxide cells, operating sequentially between power-producing fuel cell mode and fuel-producing electrolysis mode, have the capability to provide highly efficient, scalable electricity storage. However, challenges ranging from cell performance and durability to system integration must be addressed before widespread adoption. One central challenge of the system design is establishing effective thermal management in the two distinct operating modes. This work leverages an operating strategy to use carbonaceous reactant species and operate at intermediate stack temperature (650 °C) to promote exothermic fuel-synthesis reactions that thermally self-sustain the electrolysis process. We present performance of a doped lanthanum-gallate (LSGM) electrolyte solid oxide cell that shows high efficiency in both operating modes at 650 °C. A physically based electrochemical model is calibrated to represent the cell performance and used to simulate roundtrip operation for conditions unique to these reversible systems. Design decisions related to system operation are evaluated using the cell model including current density, fuel and oxidant reactant compositions, and flow configuration. The analysis reveals tradeoffs between electrical efficiency, thermal management, energy density, and durability.

  4. Technical Evaluation of Superconducting Fault Current Limiters Used in a Micro-Grid by Considering the Fault Characteristics of Distributed Generation, Energy Storage and Power Loads

    Directory of Open Access Journals (Sweden)

    Lei Chen

    2016-09-01

    Full Text Available Concerning the development of a micro-grid integrated with multiple intermittent renewable energy resources, one of the main issues is related to the improvement of its robustness against short-circuit faults. In a sense, the superconducting fault current limiter (SFCL can be regarded as a feasible approach to enhance the transient performance of a micro-grid under fault conditions. In this paper, the fault transient analysis of a micro-grid, including distributed generation, energy storage and power loads, is conducted, and regarding the application of one or more flux-coupling-type SFCLs in the micro-grid, an integrated technical evaluation method considering current-limiting performance, bus voltage stability and device cost is proposed. In order to assess the performance of the SFCLs and verify the effectiveness of the evaluation method, different fault cases of a 10-kV micro-grid with photovoltaic (PV, wind generator and energy storage are simulated in the MATLAB software. The results show that, the efficient use of the SFCLs for the micro-grid can contribute to reducing the fault current, improving the voltage sags and suppressing the frequency fluctuations. Moreover, there will be a compromise design to fully take advantage of the SFCL parameters, and thus, the transient performance of the micro-grid can be guaranteed.

  5. Distributed storage in the plane

    NARCIS (Netherlands)

    Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper

    2013-01-01

    We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can

  6. Distributed storage in the plane

    NARCIS (Netherlands)

    Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper

    2014-01-01

    We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can

  7. Distributed storage in the plane

    NARCIS (Netherlands)

    Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper

    2013-01-01

    We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can

  8. Distributed storage in the plane

    NARCIS (Netherlands)

    Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper

    2014-01-01

    We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can

  9. Storage Allocation for Multi-Class Distributed Data Storage Systems

    OpenAIRE

    Roshandeh, Koosha Pourtahmasi; Noori, Moslem; Ardakani, Masoud; Tellambura, Chintha

    2017-01-01

    Distributed storage systems (DSSs) provide a scalable solution for reliably storing massive amounts of data coming from various sources. Heterogeneity of these data sources often means different data classes (types) exist in a DSS, each needing a different level of quality of service (QoS). As a result, efficient data storage and retrieval processes that satisfy various QoS requirements are needed. This paper studies storage allocation, meaning how data of different classes must be spread ove...

  10. A Review of Energy Storage Technologies

    DEFF Research Database (Denmark)

    Connolly, David

    2010-01-01

    -alone technology that will be utilised in Ireland for the integration of fluctuating renewable energy. However, the HESS, TESS, and EVs are the also very promising, but require more research to remove uncertainty surrounding their benefits and costs. For some countries, CAES could be a more suitable technology......), Battery Energy Storage (BES), Flow Battery Energy Storage (FBES), Flywheel Energy Storage (FES), Supercapacitor Energy Storage (SCES), Superconducting Magnetic Energy Storage (SMES), Hydrogen Energy Storage System (HESS), Thermal Energy Storage (TES), and Electric Vehicles (EVs). The objective...... was to identify the following for each: 1. How it works 2. Advantages 3. Applications 4. Cost 5. Disadvantages 6. Future A brief comparison was then completed to indicate the broad range of operating characteristics available for energy storage technologies. It was concluded that PHES is the most likely stand...

  11. Autonomous control of distributed storages in microgrids

    DEFF Research Database (Denmark)

    Loh, Poh Chiang; Blaabjerg, Frede

    2011-01-01

    charging energy only when excess generation capacity is available. As generation capacity drops or demand increases, energy drawn by the storages decreases spontaneously, until full source capacity is near. At which point, the storages release their stored energy for meeting the extra load demand...

  12. Energy Storage for Aerospace Applications

    Science.gov (United States)

    Perez-Davis, Marla E.; Loyselle, Patricia L.; Hoberecht, Mark A.; Manzo, Michelle A.; Kohout, Lisa L.; Burke, Kenneth A.; Cabrera, Carlos R.

    2001-01-01

    The NASA Glenn Research Center (GRC) has long been a major contributor to the development and application of energy storage technologies for NASAs missions and programs. NASA GRC has supported technology efforts for the advancement of batteries and fuel cells. The Electrochemistry Branch at NASA GRC continues to play a critical role in the development and application of energy storage technologies, in collaboration with other NASA centers, government agencies, industry and academia. This paper describes the work in batteries and fuel cell technologies at the NASA Glenn Research Center. It covers a number of systems required to ensure that NASAs needs for a wide variety of systems are met. Some of the topics covered are lithium-based batteries, proton exchange membrane (PEM) fuel cells, and nanotechnology activities. With the advances of the past years, we begin the 21st century with new technical challenges and opportunities as we develop enabling technologies for batteries and fuel cells for aerospace applications.

  13. Thermal energy storage program description

    Energy Technology Data Exchange (ETDEWEB)

    Reimers, E. [Dept. of Energy, Washington, DC (United States)

    1989-03-01

    The U.S. Department of Energy (DOE) has sponsored applied research, development, and demonstration of technologies aimed at reducing energy consumption and encouraging replacement of premium fuels (notably oil) with renewable or abundant indigenous fuels. One of the technologies identified as being able to contribute to these goals is thermal energy storage (TES). Based on the potential for TES to contribute to the historic mission of the DOE and to address emerging energy issues related to the environment, a program to develop specific TES technologies for diurnal, industrial, and seasonal applications is underway. Currently, the program is directed toward three major application targets: (1) TES development for efficient off-peak building heating and cooling, (2) development of advanced TES building materials, and (3) TES development to reduce industrial energy consumption.

  14. Flywheel Energy Storage technology workshop

    Energy Technology Data Exchange (ETDEWEB)

    O`Kain, D.; Howell, D. [comps.

    1993-12-31

    Advances in recent years of high strength/lightweight materials, high performance magnetic bearings, and power electronics technology has spurred a renewed interest by the transportation, utility, and manufacturing industries in Flywheel Energy Storage (FES) technologies. FES offers several advantages over conventional electro-chemical energy storage, such as high specific energy and specific power, fast charging time, long service life, high turnaround efficiency (energy out/energy in), and no hazardous/toxic materials or chemicals are involved. Potential applications of FES units include power supplies for hybrid and electric vehicles, electric vehicle charging stations, space systems, and pulsed power devices. Also, FES units can be used for utility load leveling, uninterruptable power supplies to protect electronic equipment and electrical machinery, and for intermittent wind or photovoltaic energy sources. The purpose of this workshop is to provide a forum to highlight technologies that offer a high potential to increase the performance of FES systems and to discuss potential solutions to overcome present FES application barriers. This document consists of viewgraphs from 27 presentations.

  15. Thermal energy storage test facility

    Science.gov (United States)

    Ternes, M. P.

    1981-03-01

    Two loops making up the facility, using either air or liquid as the thermal transport fluid, are described. These loops will be capable of cycling residential-size thermal energy storage units through conditions simulating solar or off-peak electricity applications to evaluate the unit's performance. Construction of the liquid cycling loop was completed, and testing of thermal stratification techniques for hot and cold water is reported.

  16. Graphenal polymers for energy storage.

    Science.gov (United States)

    Li, Xianglong; Song, Qi; Hao, Long; Zhi, Linjie

    2014-06-12

    A key to improve the electrochemical performance of energy storage systems (e.g., lithium ion batteries and supercapacitors) is to develop advanced electrode materials. In the last few years, although originating from the unique structure and property of graphene, interest has expanded beyond the originally literally defined graphene into versatile integration of numerous intermediate structures lying between graphene and organic polymer, particularly for the development of new electrode materials for energy storage devices. Notably, diverse designations have shaded common characteristics of the molecular configurations of these newly-emerging materials, severely impeding the design, synthesis, tailoring, functionalization, and control of functional electrode materials in a rational and systematical manner. This concept paper highlights all these intermediate materials, specifically comprising graphene subunits intrinsically interconnected by organic linkers or fractions, following a general concept of graphenal polymers. Combined with recent advances made by our group and others, two representative synthesis approaches (bottom-up and top-down) for graphenal polymers are outlined, as well as the structure-property relationships of these graphenal polymers as energy storage electrode materials are discussed.

  17. Distributed Energy Implementation Options

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Chandralata N [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-13

    This presentation covers the options for implementing distributed energy projects. It distinguishes between options available for distributed energy that is government owned versus privately owned, with a focus on the privately owned options including Energy Savings Performance Contract Energy Sales Agreements (ESPC ESAs). The presentation covers the new ESPC ESA Toolkit and other Federal Energy Management Program resources.

  18. Electrochemical Energy Storage Technical Team Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-01

    This U.S. DRIVE electrochemical energy storage roadmap describes ongoing and planned efforts to develop electrochemical energy storage technologies for plug-in electric vehicles (PEVs). The Energy Storage activity comprises a number of research areas (including advanced materials research, cell level research, battery development, and enabling R&D which includes analysis, testing and other activities) for advanced energy storage technologies (batteries and ultra-capacitors).

  19. Energy storage device with large charge separation

    Energy Technology Data Exchange (ETDEWEB)

    Holme, Timothy P.; Prinz, Friedrich B.; Iancu, Andrei

    2016-04-12

    High density energy storage in semiconductor devices is provided. There are two main aspects of the present approach. The first aspect is to provide high density energy storage in semiconductor devices based on formation of a plasma in the semiconductor. The second aspect is to provide high density energy storage based on charge separation in a p-n junction.

  20. Underground Energy Storage Program. 1983 annual summary

    Energy Technology Data Exchange (ETDEWEB)

    Kannberg, L.D.

    1984-06-01

    The Underground Energy Storage Program approach, structure, history, and milestones are described. Technical activities and progress in the Seasonal Thermal Energy Storage and Compressed Air Energy Storage components of the program are then summarized, documenting the work performed and progress made toward resolving and eliminating technical and economic barriers associated with those technologies. (LEW)

  1. Charging Graphene for Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jun

    2014-10-06

    Since 2004, graphene, including single atomic layer graphite sheet, and chemically derived graphene sheets, has captured the imagination of researchers for energy storage because of the extremely high surface area (2630 m2/g) compared to traditional activated carbon (typically below 1500 m2/g), excellent electrical conductivity, high mechanical strength, and potential for low cost manufacturing. These properties are very desirable for achieving high activity, high capacity and energy density, and fast charge and discharge. Chemically derived graphene sheets are prepared by oxidation and reduction of graphite1 and are more suitable for energy storage because they can be made in large quantities. They still contain multiply stacked graphene sheets, structural defects such as vacancies, and oxygen containing functional groups. In the literature they are also called reduced graphene oxide, or functionalized graphene sheets, but in this article they are all referred to as graphene for easy of discussion. Two important applications, batteries and electrochemical capacitors, have been widely investigated. In a battery material, the redox reaction occurs at a constant potential (voltage) and the energy is stored in the bulk. Therefore, the energy density is high (more than 100 Wh/kg), but it is difficult to rapidly charge or discharge (low power, less than 1 kW/kg)2. In an electrochemical capacitor (also called supercapacitors or ultracapacitor in the literature), the energy is stored as absorbed ionic species at the interface between the high surface area carbon and the electrolyte, and the potential is a continuous function of the state-of-charge. The charge and discharge can happen rapidly (high power, up to 10 kW/kg) but the energy density is low, less than 10 Wh/kg2. A device that can have both high energy and high power would be ideal.

  2. Solar-energy storage-systems analysis

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, R W

    1981-04-01

    Systems analysis activities at Brookhaven National Laboratory (BNL) related to energy storage in solar applications are described, and the purpose, methods and, where available, the results of each study are summarized. Areas of investigation include storage of electrical and thermal energy in solar total energy systems, a theoretical investigation of the value of storage, and the national fuel displacement potential of semi-passive solar storage walls. Investigations of the cost effectiveness of a spectrum of passive solar storage devices and the value of several possible improvements in these devices constitutes BNL's contribution to the Solar Applications Analysis for Energy Storage (SAAES) project.

  3. Economics of compressed air energy storage employing thermal energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Schulte, S.C.; Reilly, R.W.

    1979-11-01

    The approach taken in this study is to adopt system design and capital cost estimates from three independent CAES studies (eight total designs) and, by supplying a common set of fuel/energy costs and economic assumptions in conjunction with a common methodology, to arrive at a series of levelized energy costs over the system's lifetime. In addition, some analyses are provided to gauge the sensitivity of these levelized energy costs to fuel and compression energy costs and to system capacity factors. The systems chosen for comparison are of four generic types: conventional CAES, hybrid CAES, adiabatic CAES, and an advanced-design gas turbine (GT). In conventional CAES systems the heat of compression generated during the storage operation is rejected to the environment, and later, during the energy-generation phase, turbine fuel must be burned to reheat the compressed air. In the hybrid systems some of the heat of compression is stored and reapplied later during the generation phase, thereby reducing turbine fuel requirements. The adiabatic systems store adequate thermal energy to eliminate the need for turbine fuel entirely. The gas turbine is included within the report for comparison purposes; it is an advanced-design turbine, one that is expected to be available by 1985.

  4. Electric utility applications of hydrogen energy storage systems

    Energy Technology Data Exchange (ETDEWEB)

    Swaminathan, S.; Sen, R.K.

    1997-10-15

    This report examines the capital cost associated with various energy storage systems that have been installed for electric utility application. The storage systems considered in this study are Battery Energy Storage (BES), Superconducting Magnetic Energy Storage (SMES) and Flywheel Energy Storage (FES). The report also projects the cost reductions that may be anticipated as these technologies come down the learning curve. This data will serve as a base-line for comparing the cost-effectiveness of hydrogen energy storage (HES) systems in the electric utility sector. Since pumped hydro or compressed air energy storage (CAES) is not particularly suitable for distributed storage, they are not considered in this report. There are no comparable HES systems in existence in the electric utility sector. However, there are numerous studies that have assessed the current and projected cost of hydrogen energy storage system. This report uses such data to compare the cost of HES systems with that of other storage systems in order to draw some conclusions as to the applications and the cost-effectiveness of hydrogen as a electricity storage alternative.

  5. Distributions of energy storage rate and microstructural evolution in the area of plastic strain localization during uniaxial tension of austenitic steel

    Science.gov (United States)

    Oliferuk, W.; Maj, M.

    2015-08-01

    The presented work is devoted to an experimental determination of the energy storage rate in the area of strain localization. The experimental procedure involves two complementary techniques: i.e. infrared thermography (IRT) and visible light imaging. The results of experiments have shown that during the evolution of plastic strain localization the energy storage rate in some areas of the deformed specimen drops to zero. To interpret the decrease of the energy storage rate in terms of micro-mechanisms, microstructural observations using Transmission Electron Microscopy (TEM) and Electron Back Scattered Diffraction (EBSC) were performed. On the basis of microstructural studies it is believed that a 0 value of energy storage rate corresponds to the state in which only two dominant components of the texture appear, creating conditions for crystallographic shear banding.

  6. Sizing of Offshore Wind Energy Storage

    OpenAIRE

    2014-01-01

    Energy storage has the potential to provide a key benefit for intermittent energy sources such as offshore wind by providing a method to store excess energy to be used when the wind no longer blows. However, to date energy storage has always been a fairly cost prohibitive option, particularly in offshore environments where the technology has not even reached commercial status. To properly assess the potential of energy storage, this thesis proposes a MatLab cost optimisation model which deter...

  7. Nanocarbons for advanced energy storage

    CERN Document Server

    Feng, Xinliang

    2015-01-01

    This first volume in the series on nanocarbons for advanced applications presents the latest achievements in the design, synthesis, characterization, and applications of these materials for electrochemical energy storage. The highly renowned series and volume editor, Xinliang Feng, has put together an internationally acclaimed expert team who covers nanocarbons such as carbon nanotubes, fullerenes, graphenes, and porous carbons. The first two parts focus on nanocarbon-based anode and cathode materials for lithium ion batteries, while the third part deals with carbon material-based supercapacit

  8. Improving wind power quality with energy storage

    DEFF Research Database (Denmark)

    Rasmussen, Claus Nygaard

    2009-01-01

    The results of simulation of the influence of energy storage on wind power quality are presented. Simulations are done using a mathematical model of energy storage. Results show the relation between storage power and energy, and the obtained increase in minimum available power from the combination...... of wind and storage. The introduction of storage enables smoothening of wind power on a timescale proportional to the storage energy. Storage does not provide availability of wind power at all times, but allows for a certain fraction of average power in a given timeframe to be available with high...... probability. The amount of storage capacity necessary for significant wind power quality improvement in a given period is found to be 20 to 40% of the energy produced in that period. The necessary power is found to be 80 to 100% of the average power of the period....

  9. Seasonal sensible thermal energy storage solutions

    Directory of Open Access Journals (Sweden)

    Lavinia Gabriela SOCACIU

    2012-08-01

    Full Text Available The thermal energy storage can be defined as the temporary storage of thermal energy at high or low temperatures. Thermal energy storage is an advances technology for storing thermal energy that can mitigate environmental impacts and facilitate more efficient and clean energy systems. Seasonal thermal energy storage has a longer thermal storage period, generally three or more months. This can contribute significantly to meeting society`s need for heating and cooling. The objectives of thermal energy storage systems are to store solar heat collected in summer for space heating in winter. This concept is not new; it is been used and developed for centuries because is playing an important role in energy conservation and contribute significantly to improving the energy efficiency and reducing the gas emissions to the atmosphere.

  10. Scalable Planning for Energy Storage in Energy and Reserve Markets

    OpenAIRE

    Xu, Bolun; Wang, Yishen; Dvorkin, Yury; Fernandez-Blanco, Ricardo; Silva-Monroy, Cesar A.; Watson, Jean-Paul; Kirschen, Daniel S.

    2016-01-01

    Energy storage can facilitate the integration of renewable energy resources by providing arbitrage and ancillary services. Jointly optimizing energy and ancillary services in a centralized electricity market reduces the system's operating cost and enhances the profitability of energy storage systems. However, achieving these objectives requires that storage be located and sized properly. We use a bi-level formulation to optimize the location and size of energy storage systems which perform en...

  11. Commercialization of aquifer thermal energy storage technology

    Energy Technology Data Exchange (ETDEWEB)

    Hattrup, M.P.; Weijo, R.O.

    1989-09-01

    Pacific Northwest Laboratory (PNL) conducted this study for the US Department of Energy's (DOE) Office of Energy Storage and Distribution. The purpose of the study was to develop and screen a list of potential entry market applications for aquifer thermal energy storage (ATES). Several initial screening criteria were used to identify promising ATES applications. These include the existence of an energy availability/usage mismatch, the existence of many similar applications or commercial sites, the ability to utilize proven technology, the type of location, market characteristics, the size of and access to capital investment, and the number of decision makers involved. The in-depth analysis identified several additional screening criteria to consider in the selection of an entry market application. This analysis revealed that the best initial applications for ATES are those where reliability is acceptable, and relatively high temperatures are allowable. Although chill storage was the primary focus of this study, applications that are good candidates for heat ATES were also of special interest. 11 refs., 3 tabs.

  12. Energy storage for electrical systems in the USA

    National Research Council Canada - National Science Library

    Eugene Freeman; Davide Occello; Frank Barnes

    2016-01-01

    Energy storage is becoming increasingly important as renewable generation sources such as Wind Turbine and Photo Voltaic Solar are added to the mix in electrical power generation and distribution systems...

  13. Static and Dynamic Stability Analysis of Distributed Energy Resources Components with Storage Devices and Loads for Smart Grids

    DEFF Research Database (Denmark)

    Mihet-Popa, Lucian; Groza, V.

    2011-01-01

    of the Smart Grids (SGs). A SG can operate interconnected to the main distribution grid or in islanded mode. This paper presents experimental tests for static and dynamic stability analysis carried out in a dedicated laboratory for research in distributed control and smart grid with a high share of renewable...... are required under different operation modes and loads. The testing reporting here includes three modes of operation: stand alone, parallel/hybrid and grid connection....

  14. Applications and challenges for thermal energy storage

    Science.gov (United States)

    Kannberg, L. D.; Tomlinson, J. T.

    1991-04-01

    New thermal energy storage (TES) technologies are being developed and applied as society strives to relieve increasing energy and environmental stresses. Applications for these new technologies range from residential and district heating and cooling using waste and solar energy, to high-temperature energy storage for power production and industrial processes. In the last two decades there has been great interest and development of heat storage systems, primarily for residential and commercial buildings. While development has continued, the rate of advancement has slowed with current technology considered adequate for electrically charged heat storage furnaces. Use of chill storage for building diurnal cooling has received substantial development.

  15. A Hybrid Estimator for Active/Reactive Power Control of Single-Phase Distributed Generation Systems with Energy Storage

    OpenAIRE

    Pahlevani, Majid; Eren, Suzan; Guerrero, Josep M.; Jain, Praveen

    2016-01-01

    This paper presents a new active/reactive power closed-loop control system for a hybrid renewable energy generation system used for single-phase residential/commercial applications.The proposed active/reactive control method includes a hybrid estimator, which is able to quickly and accurately estimate the active/reactive power values. The proposed control system enables the hybrid renewable energy generation system to be able to perform real-time grid interconnection services such as active v...

  16. Allocations for Heterogenous Distributed Storage

    CERN Document Server

    Ntranos, Vasileios; Dimakis, Alexandros G

    2012-01-01

    We study the problem of storing a data object in a set of data nodes that fail independently with given probabilities. Our problem is a natural generalization of a homogenous storage allocation problem where all the nodes had the same reliability and is naturally motivated for peer-to-peer and cloud storage systems with different types of nodes. Assuming optimal erasure coding (MDS), the goal is to find a storage allocation (i.e, how much to store in each node) to maximize the probability of successful recovery. This problem turns out to be a challenging combinatorial optimization problem. In this work we introduce an approximation framework based on large deviation inequalities and convex optimization. We propose two approximation algorithms and study the asymptotic performance of the resulting allocations.

  17. The chemistry of energy conversion and storage.

    Science.gov (United States)

    Su, Dang Sheng

    2014-05-01

    What's in store: The sustainable development of our society requires the conversion and storage of renewable energy, and these should be scaled up to serve the global primary energy consumption. This special issue on "The Chemistry of Energy Conversion and Storage", assembled by guest editor Dangsheng Su, contains papers dealing with these aspects, and highlights important developments in the chemistry of energy conversion and storage during the last two years.

  18. Nuclear Hybrid Energy Systems: Molten Salt Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    P. Sabharwall; M. Green; S.J. Yoon; S.M. Bragg-Sitton; C. Stoots

    2014-07-01

    With growing concerns in the production of reliable energy sources, the next generation in reliable power generation, hybrid energy systems, are being developed to stabilize these growing energy needs. The hybrid energy system incorporates multiple inputs and multiple outputs. The vitality and efficiency of these systems resides in the energy storage application. Energy storage is necessary for grid stabilizing and storing the overproduction of energy to meet peak demands of energy at the time of need. With high thermal energy production of the primary nuclear heat generation source, molten salt energy storage is an intriguing option because of its distinct properties. This paper will discuss the different energy storage options with the criteria for efficient energy storage set forth, and will primarily focus on different molten salt energy storage system options through a thermodynamic analysis

  19. Electromagnetic energy storage and power dissipation in nanostructures

    CERN Document Server

    Zhao, J M

    2014-01-01

    The processes of storage and dissipation of electromagnetic energy in nanostructures depend on both the material properties and the geometry. In this paper, the distributions of local energy density and power dissipation in nanogratings are investigated using the rigorous coupled-wave analysis. It is demonstrated that the enhancement of absorption is accompanied by the enhancement of energy storage both for material at the resonance of its dielectric function described by the classical Lorentz oscillator and for nanostructures at the resonance induced by its geometric arrangement. The appearance of strong local electric field in nanogratings at the geometry-induced resonance is directly related to the maximum electric energy storage. Analysis of the local energy storage and dissipation can also help gain a better understanding of the global energy storage and dissipation in nanostructures for photovoltaic and heat transfer applications.

  20. Enhanced distributed energy resource system

    Science.gov (United States)

    Atcitty, Stanley; Clark, Nancy H.; Boyes, John D.; Ranade, Satishkumar J.

    2007-07-03

    A power transmission system including a direct current power source electrically connected to a conversion device for converting direct current into alternating current, a conversion device connected to a power distribution system through a junction, an energy storage device capable of producing direct current connected to a converter, where the converter, such as an insulated gate bipolar transistor, converts direct current from an energy storage device into alternating current and supplies the current to the junction and subsequently to the power distribution system. A microprocessor controller, connected to a sampling and feedback module and the converter, determines when the current load is higher than a set threshold value, requiring triggering of the converter to supply supplemental current to the power transmission system.

  1. A Hybrid Estimator for Active/Reactive Power Control of Single-Phase Distributed Generation Systems with Energy Storage

    DEFF Research Database (Denmark)

    Pahlevani, Majid; Eren, Suzan; Guerrero, Josep M.;

    2016-01-01

    This paper presents a new active/reactive power closed-loop control system for a hybrid renewable energy generation system used for single-phase residential/commercial applications. The proposed active/reactive control method includes a hybrid estimator, which is able to quickly and accurately...... estimate the active/reactive power values. The proposed control system enables the hybrid renewable energy generation system to be able to perform real-time grid interconnection services such as active voltage regulation, active power control, and fault ride-through.Simulation and experimental results...... demonstrate the superior performance of the proposed closed-loop control system....

  2. Merits of flywheels for spacecraft energy storage

    Science.gov (United States)

    Gross, S.

    1984-01-01

    Flywheel energy storage systems which have a very good potential for use in spacecraft are discussed. This system can be superior to alkaline secondary batteries and regenerable fuel cells in most of the areas that are important in spacecraft applications. Of special importance, relative to batteries, are lighter weight, longer cycle and operating life, and high efficiency which minimizes solar array size and the amount of orbital makeup fuel required. Flywheel systems have a long shelf life, give a precise state of charge indication, have modest thermal control needs, are capable of multiple discharges per orbit, have simple ground handling needs, and have characteristics which would be useful for military applications. The major disadvantages of flywheel energy storage systems are that: power is not available during the launch phase without special provisions; and in flight failure of units may force shutdown of good counter rotating units, amplifying the effects of failure and limiting power distribution system options; no inherent emergency power capability unless specifically designed for, and a high level of complexity compared with batteries. The potential advantages of the flywheel energy storage system far outweigh the disadvantages.

  3. Distributed Energy Technology Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Distributed Energy Technologies Laboratory (DETL) is an extension of the power electronics testing capabilities of the Photovoltaic System Evaluation Laboratory...

  4. Energy storage benefits and market analysis handbook : a study for the DOE Energy Storage Systems Program.

    Energy Technology Data Exchange (ETDEWEB)

    Eyer, James M. (Distributed Utility Associates, Livermore, CA); Corey, Garth P.; Iannucci, Joseph J., Jr. (Distributed Utility Associates, Livermore, CA)

    2004-12-01

    This Guide describes a high level, technology-neutral framework for assessing potential benefits from and economic market potential for energy storage used for electric utility-related applications. In the United States use of electricity storage to support and optimize transmission and distribution (T&D) services has been limited due to high storage system cost and by limited experience with storage system design and operation. Recent improvement of energy storage and power electronics technologies, coupled with changes in the electricity marketplace, indicate an era of expanding opportunity for electricity storage as a cost-effective electric resource. Some recent developments (in no particular order) that drive the opportunity include: (1) states adoption of the renewables portfolio standard (RPS), which may increased use of renewable generation with intermittent output, (2) financial risk leading to limited investment in new transmission capacity, coupled with increasing congestion on some transmission lines, (3) regional peaking generation capacity constraints, and (4) increasing emphasis on locational marginal pricing (LMP).

  5. Electrical Energy Storage for Renewable Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Helms, C. R.; Cho, K. J.; Ferraris, John; Balkus, Ken; Chabal, Yves; Gnade, Bruce; Rotea, Mario; Vasselli, John

    2012-08-31

    This program focused on development of the fundamental understanding necessary to significantly improve advanced battery and ultra-capacitor materials and systems to achieve significantly higher power and energy density on the one hand, and significantly lower cost on the other. This program spanned all the way from atomic-level theory, to new nanomaterials syntheses and characterization, to system modeling and bench-scale technology demonstration. Significant accomplishments are detailed in each section. Those particularly noteworthy include: • Transition metal silicate cathodes with 2x higher storage capacity than commercial cobalt oxide cathodes were demonstrated. • MnO₂ nanowires, which are a promising replacement for RuO₂, were synthesized • PAN-based carbon nanofibers were prepared and characterized with an energy density 30-times higher than current ultracapacitors on the market and comparable to lead-acid batteries • An optimization-based control strategy for real-time power management of battery storage in wind farms was developed and demonstrated. • PVDF films were developed with breakdown strengths of > 600MVm⁻¹, a maximum energy density of approximately 15 Jcm⁻³, and an average dielectric constant of 9.8 (±1.2). Capacitors made from these films can support a 10-year lifetime operating at an electric field of 200 MV m⁻¹. This program not only delivered significant advancements in fundamental understanding and new materials and technology, it also showcased the power of the cross-functional, multi-disciplinary teams at UT Dallas and UT Tyler for such work. These teams are continuing this work with other sources of funding from both industry and government.

  6. Flywheel energy storage for spacecraft

    Science.gov (United States)

    Gross, S.

    1984-01-01

    Flywheel energy storage systems have been studied to determine their potential for use in spacecraft. This system was found to be superior to alkaline secondary batteries and regenerative fuel cells in most of the areas that are important in spacecraft applications. Of special importance, relative to batteries, are lighter weight, longer cycle and operating life, and high efficiency which minimizes solar array size and the amount of orbital makeup fuel required. In addition, flywheel systems have a long shelf life, give a precise state of charge indication, have modest thermal control needs, are capable of multiple discharges per orbit, have simple ground handling needs, and have the capability of generating extremely high power for short durations.

  7. System-Level Operational and Adequacy Impact Assessment of Photovoltaic and Distributed Energy Storage, with Consideration of Inertial Constraints, Dynamic Reserve and Interconnection Flexibility

    Directory of Open Access Journals (Sweden)

    Lingxi Zhang

    2017-07-01

    Full Text Available The growing penetration of solar photovoltaic (PV systems requires a fundamental understanding of its impact at a system-level. Furthermore, distributed energy storage (DES technologies, such as batteries, are attracting great interest owing to their ability to provide support to systems with large-scale renewable generation, such as PV. In this light, the system-level impacts of PV and DES are assessed from both operational and adequacy perspectives. Different control strategies for DES are proposed, namely: (1 centralised, to support system operation in the presence of increasing requirements on system ramping and frequency control; and (2 decentralised, to maximise the harnessing of solar energy from individual households while storing electricity generated by PV panels to provide system capacity on request. The operational impacts are assessed by deploying a multi-service unit commitment model with consideration of inertial constraints, dynamic reserve allocation, and interconnection flexibility, while the impacts on adequacy of supply are analysed by assessing the capacity credit of PV and DES through different metrics. The models developed are then applied to different future scenarios for the Great Britain power system, whereby an electricity demand increase due to electrification is also considered. The numerical results highlight the importance of interconnectors to provide flexibility. On the other hand, provision of reserves, as opposed to energy arbitrage, from DES that are integrated into system operation is seen as the most effective contribution to improve system performance, which in turn also decreases the role of interconnectors. DES can also contribute to providing system capacity, but to an extent that is limited by their individual and aggregated energy availability under different control strategies.

  8. Battery energy storage market feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Kraft, S. [Frost and Sullivan, Mountain View, CA (United States); Akhil, A. [Sandia National Labs., Albuquerque, NM (United States). Energy Storage Systems Analysis and Development Dept.

    1997-07-01

    Under the sponsorship of the Department of Energy`s Office of Utility Technologies, the Energy Storage Systems Analysis and Development Department at Sandia National Laboratories (SNL) contracted Frost and Sullivan to conduct a market feasibility study of energy storage systems. The study was designed specifically to quantify the energy storage market for utility applications. This study was based on the SNL Opportunities Analysis performed earlier. Many of the groups surveyed, which included electricity providers, battery energy storage vendors, regulators, consultants, and technology advocates, viewed energy storage as an important enabling technology to enable increased use of renewable energy and as a means to solve power quality and asset utilization issues. There are two versions of the document available, an expanded version (approximately 200 pages, SAND97-1275/2) and a short version (approximately 25 pages, SAND97-1275/1).

  9. Storage, transmission and distribution of hydrogen

    Science.gov (United States)

    Kelley, J. H.; Hagler, R., Jr.

    1979-01-01

    Current practices and future requirements for the storage, transmission and distribution of hydrogen are reviewed in order to identify inadequacies to be corrected before hydrogen can achieve its full potential as a substitute for fossil fuels. Consideration is given to the storage of hydrogen in underground solution-mined salt caverns, portable high-pressure containers and dewars, pressure vessels and aquifers and as metal hydrides, hydrogen transmission in evacuated double-walled insulated containers and by pipeline, and distribution by truck and internal distribution networks. Areas for the improvement of these techniques are indicated, and these technological deficiencies, including materials development, low-cost storage and transmission methods, low-cost, long-life metal hydrides and novel methods for hydrogen storage, are presented as challenges for research and development.

  10. Thermal energy storage apparatus, controllers and thermal energy storage control methods

    Science.gov (United States)

    Hammerstrom, Donald J.

    2016-05-03

    Thermal energy storage apparatus, controllers and thermal energy storage control methods are described. According to one aspect, a thermal energy storage apparatus controller includes processing circuitry configured to access first information which is indicative of surpluses and deficiencies of electrical energy upon an electrical power system at a plurality of moments in time, access second information which is indicative of temperature of a thermal energy storage medium at a plurality of moments in time, and use the first and second information to control an amount of electrical energy which is utilized by a heating element to heat the thermal energy storage medium at a plurality of moments in time.

  11. Efficiency of Compressed Air Energy Storage

    OpenAIRE

    Elmegaard, Brian; Brix, Wiebke

    2011-01-01

    The simplest type of a Compressed Air Energy Storage (CAES) facility would be an adiabatic process consisting only of a compressor, a storage and a turbine, compressing air into a container when storing and expanding when producing. This type of CAES would be adiabatic and would if the machines were reversible have a storage efficiency of 100%. However, due to the specific capacity of the storage and the construction materials the air is cooled during and after compression in practice, making...

  12. 4th international renewable energy storage conference (IRES 2009)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    Within the 4th International Renewable Energy Storage Conference of The European Association for Renewable Energy (Bonn, Federal Republic of Germany) and The World Council for Renewable Energy (Bonn, Federal Republic of Germany) between 24th and 25 November, 2009, in Berlin (Federal Republic of Germany), the following lectures were held: (1) The World Wind Energy Association (A. Kane); (2) The contribution of wind power to the energy supply of tomorrow (H. Albers); (3) Intelligent energy systems for the integration of renewable energies (A.-C. Agricola); (4) 100% Renewable energies: From fossil baseload plants to renewable plants for basic supply (M. Willenbacher); (5) High-performance Li-ion technology for stationary and mobile applications (A. Gutsch); (6) Energy storage in geological underground - Competition of use at storage formations (L. Dietrich); (7) E-mobility concepts for model region ''Rhein-Ruhr'' in North Rhine Westphalia (G.-U. Funk); (8) Photovoltaic energy storage for a better energy management in residential buildings (S. Pincemin); (9) Self-consuming photovoltaic energy in Germany - Impact on energy flows, business cases, and the distribution grid (M. Braun); (10) Local energy systems -optimized for local consumption of self-produced electricity (B. Wille-Haussmann); (11) Assessing the economics of distributed storage systems at the end consumer level (K.-H. Ahlert); (12) A new transportation system for heat on a wide temperature range (S. Gschwander); (13) Latent heat storage media for cooling applications (C. Doetsch); (14) Numerical and experimental analysis of latent heat storage systems for mobile application (F. Roesler); (15) CO{sub 2}-free heat supply from waste heat (H.-W. Etzkorn); (16) Stationary Li-Ion-technology applications for dispatchable power (C. Kolligs); (17) Redox-flow batteries - Electric storage systems for renewable energy (T. Smolinka); (18) Energy storage by means of flywheels (H. Kielsein); (19

  13. Symposium on Energy Storage Materials Energy and Fuel Division, 246th ACS National Meeting

    Science.gov (United States)

    2015-04-17

    Approved for Public Release; Distribution Unlimited Final Report: Symposium on Energy Storage Materials Energy and Fuel Division, 246th ACS National...Research Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 ARO, symposium, batteries, energy, ACS REPORT DOCUMENTATION PAGE 11. SPONSOR...journals: Final Report: Symposium on Energy Storage Materials Energy and Fuel Division, 246th ACS National Meeting Report Title The symposium took place on

  14. Distributed Storage Codes through Hadamard Designs

    CERN Document Server

    Papailiopoulos, Dimitris S

    2011-01-01

    In distributed storage systems that employ erasure coding, the issue of minimizing the total {\\it repair bandwidth} required to exactly regenerate a storage node after a failure arises. This repair bandwidth depends on the structure of the storage code and the repair strategies used to restore the lost data. Minimizing it requires that undesired data during a repair align in the smallest possible spaces, using the concept of interference alignment (IA). Here, a points-on-a-lattice representation of the symbol extension IA of Cadambe {\\it et al.} provides cues to perfect IA instances which we combine with fundamental properties of Hadamard matrices to construct a new storage code with favorable repair properties. Specifically, we build an explicit $(k+2,k)$ storage code over $\\mathbb{GF}(3)$, whose single systematic node failures can be repaired with bandwidth that matches exactly the theoretical minimum. Moreover, the repair of single parity node failures generates at most the same repair bandwidth as any sys...

  15. Fuzzy-Logic-Based Gain-Scheduling Control for State-of-Charge Balance of Distributed Energy Storage Systems for DC Microgrids

    DEFF Research Database (Denmark)

    Aldana, Nelson Leonardo Diaz; Dragicevic, Tomislav; Vasquez, Juan Carlos

    2014-01-01

    -charge or deep-discharge in one of the energy storage units. Primary control in a microgrid is responsible for power sharing among units; and droop control is typically used in this stage. This paper proposes a modular and decentralized gain-scheduling control strategy based on fuzzy logic that ensures balanced...

  16. ENERGY STAR Certified Data Center Storage

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 1.0 ENERGY STAR Program Requirements for Data Center Storage that are effective as of...

  17. Nanostructures for Electrical Energy Storage (NEES) EFRC

    Data.gov (United States)

    Federal Laboratory Consortium — The Nanostructures for Electrical Energy Storage (NEES) EFRC is a multi-institutional research center, one of 46 Energy Frontier Research Centers established by the...

  18. Storage and distribution system for multimedia information

    Science.gov (United States)

    Murakami, Tokumichi

    1994-06-01

    Recent advances in technologies such as digital signal processing, LSI devices and storage media have led to an explosive growth in multimedia environment. Multimedia information services are expected to provide an information-oriented infrastructure which will integrate visual communication, broadcasting and computer services. International standardizations in video/audio coding accelerate permeation of these services into society. In this paper, from trends of R & D and international standardization in video coding techniques, an outline is given of a storage and distribution system for multimedia information, and a summary of the requirements of digital storage media.

  19. Energy investment: The many lives of energy storage

    Science.gov (United States)

    Fumagalli, Elena

    2016-07-01

    Energy storage offers potential to support a changing electricity sector, but investors remain uncertain about its attractiveness. Analysis now shows that this can be overcome for battery technology by providing more than one storage service in a single facility.

  20. Functional Carbon Materials for Electrochemical Energy Storage

    Science.gov (United States)

    Zhou, Huihui

    The ability to harvest and convert solar energy has been associated with the evolution of human civilization. The increasing consumption of fossil fuels since the industrial revolution, however, has brought to concerns in ecological deterioration and depletion of the fossil fuels. Facing these challenges, humankind is forced to seek for clean, sustainable and renewable energy resources, such as biofuels, hydraulic power, wind power, geothermal energy and other kinds of alternative energies. However, most alternative energy sources, generally in the form of electrical energy, could not be made available on a continuous basis. It is, therefore, essential to store such energy into chemical energy, which are portable and various applications. In this context, electrochemical energy-storage devices hold great promises towards this goal. The most common electrochemical energy-storage devices are electrochemical capacitors (ECs, also called supercapacitors) and batteries. In comparison to batteries, ECs posses high power density, high efficiency, long cycling life and low cost. ECs commonly utilize carbon as both (symmetric) or one of the electrodes (asymmetric), of which their performance is generally limited by the capacitance of the carbon electrodes. Therefore, developing better carbon materials with high energy density has been emerging as one the most essential challenges in the field. The primary objective of this dissertation is to design and synthesize functional carbon materials with high energy density at both aqueous and organic electrolyte systems. The energy density (E) of ECs are governed by E = CV 2/2, where C is the total capacitance and V is the voltage of the devices. Carbon electrodes with high capacitance and high working voltage should lead to high energy density. In the first part of this thesis, a new class of nanoporous carbons were synthesized for symmetric supercapacitors using aqueous Li2SO4 as the electrolyte. A unique precursor was adopted to

  1. Regenesys utility scale energy storage. Project summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This report summarises the work to date, the current situation and the future direction of a project carried out by Regenesys Technology Ltd. (RGN) to investigate the benefits of electrochemical energy storage for power generators using renewable energy sources focussing on wind energy. The background to the study is traced covering the progress of the Regenesys energy storage technology, and the milestones achieved and lessons learnt. Details are given of the planned renewable-store-market interface to allow renewable generators optimise revenue under the New Electricity Trading Arrangements (NETA) and help in the connection of the renewable energy to the electric grid system. The four integrated work programmes of the project are described and involve a system study examining market penetration of renewable generators, a technical study into connection of renewable generators and energy storage, a small scale demonstration, and a pilot scale energy storage plant at Little Barton in Cambridgeshire. Problems leading to the closure of the project are discussed.

  2. Effective energy storage from a triboelectric nanogenerator

    Science.gov (United States)

    Zi, Yunlong; Wang, Jie; Wang, Sihong; Li, Shengming; Wen, Zhen; Guo, Hengyu; Wang, Zhong Lin

    2016-03-01

    To sustainably power electronics by harvesting mechanical energy using nanogenerators, energy storage is essential to supply a regulated and stable electric output, which is traditionally realized by a direct connection between the two components through a rectifier. However, this may lead to low energy-storage efficiency. Here, we rationally design a charging cycle to maximize energy-storage efficiency by modulating the charge flow in the system, which is demonstrated on a triboelectric nanogenerator by adding a motion-triggered switch. Both theoretical and experimental comparisons show that the designed charging cycle can enhance the charging rate, improve the maximum energy-storage efficiency by up to 50% and promote the saturation voltage by at least a factor of two. This represents a progress to effectively store the energy harvested by nanogenerators with the aim to utilize ambient mechanical energy to drive portable/wearable/implantable electronics.

  3. Effective energy storage from a triboelectric nanogenerator.

    Science.gov (United States)

    Zi, Yunlong; Wang, Jie; Wang, Sihong; Li, Shengming; Wen, Zhen; Guo, Hengyu; Wang, Zhong Lin

    2016-03-11

    To sustainably power electronics by harvesting mechanical energy using nanogenerators, energy storage is essential to supply a regulated and stable electric output, which is traditionally realized by a direct connection between the two components through a rectifier. However, this may lead to low energy-storage efficiency. Here, we rationally design a charging cycle to maximize energy-storage efficiency by modulating the charge flow in the system, which is demonstrated on a triboelectric nanogenerator by adding a motion-triggered switch. Both theoretical and experimental comparisons show that the designed charging cycle can enhance the charging rate, improve the maximum energy-storage efficiency by up to 50% and promote the saturation voltage by at least a factor of two. This represents a progress to effectively store the energy harvested by nanogenerators with the aim to utilize ambient mechanical energy to drive portable/wearable/implantable electronics.

  4. Downsized superconducting magnetic energy storage systems

    Science.gov (United States)

    Palmer, David N.

    Scaled-down superconductive magnetic energy storage systems (DSMES) and superconductive magnetic energy power sources (SMEPS) are proposed for residential, commercial/retail, industrial off-peak and critical services, telephone and other communication systems, computer operations, power back-up/energy storages, power sources for space stations, and in-field military logistics/communication systems. Recent advances in high-Tc superconducting materials technology are analyzed. DSMES/SMEPS concepts are presented, and design, materials, and systems requirements are discussed. Problems ar identified, and possible solutions are offered. Comparisons are made with mechanical and primary and secondary energy storage and conversion systems.

  5. Long vs. short-term energy storage:sensitivity analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Schoenung, Susan M. (Longitude 122 West, Inc., Menlo Park, CA); Hassenzahl, William V. (,Advanced Energy Analysis, Piedmont, CA)

    2007-07-01

    This report extends earlier work to characterize long-duration and short-duration energy storage technologies, primarily on the basis of life-cycle cost, and to investigate sensitivities to various input assumptions. Another technology--asymmetric lead-carbon capacitors--has also been added. Energy storage technologies are examined for three application categories--bulk energy storage, distributed generation, and power quality--with significant variations in discharge time and storage capacity. Sensitivity analyses include cost of electricity and natural gas, and system life, which impacts replacement costs and capital carrying charges. Results are presented in terms of annual cost, $/kW-yr. A major variable affecting system cost is hours of storage available for discharge.

  6. Battery energy storage and superconducting magnetic energy storage for utility applications: A qualitative analysis

    Energy Technology Data Exchange (ETDEWEB)

    Akhil, A.A.; Butler, P.; Bickel, T.C.

    1993-11-01

    This report was prepared at the request of the US Department of Energy`s Office of Energy Management for an objective comparison of the merits of battery energy storage with superconducting magnetic energy storage technology for utility applications. Conclusions are drawn regarding the best match of each technology with these utility application requirements. Staff from the Utility Battery Storage Systems Program and the superconductivity Programs at Sandia National contributed to this effort.

  7. Compact inductive energy storage pulse power system.

    Science.gov (United States)

    K, Senthil; Mitra, S; Roy, Amitava; Sharma, Archana; Chakravarthy, D P

    2012-05-01

    An inductive energy storage pulse power system is being developed in BARC, India. Simple, compact, and robust opening switches, capable of generating hundreds of kV, are key elements in the development of inductive energy storage pulsed power sources. It employs an inductive energy storage and opening switch power conditioning techniques with high energy density capacitors as the primary energy store. The energy stored in the capacitor bank is transferred to an air cored storage inductor in 5.5 μs through wire fuses. By optimizing the exploding wire parameters, a compact, robust, high voltage pulse power system, capable of generating reproducibly 240 kV, is developed. This paper presents the full details of the system along with the experimental data.

  8. Biodigester as an energy storage system

    Energy Technology Data Exchange (ETDEWEB)

    Borges Neto, M.R.; Lopes, L.C.N. [Federal Institute of Education, Science and Technology of Sertao Pernambucano (IFSertao-PE), Petrolina, PE (Brazil)], Emails: rangel@cefetpet.br; Pinheiro Neto, J.S.; Carvalho, P.C.M. [Federal University of Ceara (UFC), Fortaleza, CE (Brazil). Dept. of Electrical Engineering], Emails: neto@tbmtextil.com.br, carvalho@dee.ufc.br; Silveira, G.C.; Moreira, A.P.; Borges, T.S.H. [Federal Institute of Education, Science and Technology of Ceara (IFCE), Fortaleza, CE (Brazil)], Emails: gcsilveira@cefet-ce.br, apmoreira@ifce.edu.br, thatyanys@yahoo.com.br

    2009-07-01

    Electricity supply for rural and remote areas is becoming an increasing priority to developing countries. The high initial cost of renewable energy based unities usually needs an energy storage system; due its operational and even replacement cost contributes to a higher final cost. The choice of energy storage systems depends on the sort and size of adopted power supply. This paper has a main goal to introduce a renewable energy based storage system weakly explored in Brazil: biogas from anaerobic digestion. It also brings a review of the main energy storage systems applied to electrical energy generation. As reference an experiment with an adapted Indian digester of 5 m{sup 3} that produced nearly 2m{sup 3} of biogas daily. The obtained biogas met the consumption of at least 4 typical Brazilian low income households with installed load of 500 W each and was enough to replace the use of 420 Ah lead-acid batteries. (author)

  9. The Role of Energy Storages in Energy Independent Croatia

    DEFF Research Database (Denmark)

    Krajačić, Goran; Mathiesen, Brian Vad; Duić, Neven

    2009-01-01

    electricity, heat and transport demands, and including renewable energy, power plants, and combined heat and power production (CHP) for district heating. Using the 2007 energy system the wind power share is increased by two energy storage options: Pumped Hydro and Heat Pumps in combination with Heat Storages...

  10. Development of fuel and energy storage technologies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    Development of fuel cell power plants is intended of high-efficiency power generation using such fuels with less air pollution as natural gas, methanol and coal gas. The closest to commercialization is phosphoric acid fuel cells, and the high in efficiency and rich in fuel diversity is molten carbonate fuel cells. The development is intended to cover a wide scope from solid electrolyte fuel cells to solid polymer electrolyte fuel cells. For new battery power storage systems, development is focused on discrete battery energy storage technologies of fixed type and mobile type (such as electric vehicles). The ceramic gas turbine technology development is purposed for improving thermal efficiency and reducing pollutants. Small-scale gas turbines for cogeneration will also be developed. Development of superconduction power application technologies is intended to serve for efficient and stable power supply by dealing with capacity increase and increase in power distribution distance due to increase in power demand. In the operations to improve the spread and general promotion systems for electric vehicles, load leveling is expected by utilizing and storing nighttime electric power. Descriptions are given also on economical city systems which utilize wide-area energy. 30 figs., 7 tabs.

  11. Memory Allocation in Distributed Storage Networks

    CERN Document Server

    Sardari, Mohsen; Fekri, Faramarz; Soljanin, Emina

    2010-01-01

    We consider the problem of distributing a file in a network of storage nodes whose storage budget is limited but at least equals to the size file. We first generate $T$ encoded symbols (from the file) which are then distributed among the nodes. We investigate the optimal allocation of $T$ encoded packets to the storage nodes such that the probability of reconstructing the file by using any $r$ out of $n$ nodes is maximized. Since the optimal allocation of encoded packets is difficult to find in general, we find another objective function which well approximates the original problem and yet is easier to optimize. We find the optimal symmetric allocation for all coding redundancy constraints using the equivalent approximate problem. We also investigate the optimal allocation in random graphs. Finally, we provide simulations to verify the theoretical results.

  12. Regenesys utility scale energy storage. Overview report of combined energy storage and renewable generation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    The first part of the paper briefly discusses the advantages and disadvantages of various forms of renewable energy sources with respect to the United Kingdom. It discusses the intermittent nature of wind and solar power and the less intermittent nature of hydro power and energy from biomass. The need to store energy generated, particularly from the intermittent sources, is discussed with special reference to electric batteries and pumped storage. If the energy cannot be stored and delivered when required, then the commercial viability of the source will be adversely affected - the economics and how this fits with NETA are discussed briefly. The second part of the paper is an overview of some relevant literature discussing (a) how the problems of fluctuating supplies may be managed, (b) an analytical assessment of the contribution from wind farms, (c) how fluctuations in wind power can be smoothed using sodium-sulfur batteries, (d) how small generators can get together and reduce trading costs and imbalance exposure under NETA, (e) the benefits of large-scale energy storage to network management and embedded generation, (f) distribution networks, (g) embedded generation and network management issues and (h) costs and benefits of embedded generation. The work was carried out as part of the DTI New and Renewable Energy Programme managed by Future Energy Solutions.

  13. Materials in energy conversion, harvesting, and storage

    CERN Document Server

    Lu, Kathy

    2014-01-01

    First authored book to address materials' role in the quest for the next generation of energy materials Energy balance, efficiency, sustainability, and so on, are some of many facets of energy challenges covered in current research. However, there has not been a monograph that directly covers a spectrum of materials issues in the context of energy conversion, harvesting and storage. Addressing one of the most pressing problems of our time, Materials in Energy Conversion, Harvesting, and Storage illuminates the roles and performance requirements of materials in energy an

  14. Energy storage in future power systems

    DEFF Research Database (Denmark)

    Rasmussen, Claus Nygaard; Østergaard, Jacob; Divya, K. C.

    2011-01-01

    Most sources of renewable power are characterised by uncontrollable and chaotic variations in power output. We here look at how energy storage may benefit renewable power generation by making it available in periods with little or no intermittent generation and thereby prevent additional...... conventional generation form being used. In addition to this, one of the strongest concerns in relation to renewable power is the instability in the electric power system that it may introduce as a result of large and relatively fast power fluctuations. An additional benefit of energy storage is therefore its...... of renewable energy. Meanwhile, the insurance of power system stability through reduction of power gradients is of major importance even at lower penetration levels and some form of energy storage therefore seems unavoidable. A variety of technologies are available for storage of energy in the power system...

  15. Energy storage in future power systems

    DEFF Research Database (Denmark)

    Rasmussen, Claus Nygaard; Østergaard, Jacob; Divya, K. C.

    2011-01-01

    Most sources of renewable power are characterised by uncontrollable and chaotic variations in power output. We here look at how energy storage may benefit renewable power generation by making it available in periods with little or no intermittent generation and thereby prevent additional...... conventional generation form being used. In addition to this, one of the strongest concerns in relation to renewable power is the instability in the electric power system that it may introduce as a result of large and relatively fast power fluctuations. An additional benefit of energy storage is therefore its...... of renewable energy. Meanwhile, the insurance of power system stability through reduction of power gradients is of major importance even at lower penetration levels and some form of energy storage therefore seems unavoidable. A variety of technologies are available for storage of energy in the power system...

  16. University of Arizona Compressed Air Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Joseph; Muralidharan, Krishna

    2012-12-31

    Boiled down to its essentials, the grant’s purpose was to develop and demonstrate the viability of compressed air energy storage (CAES) for use in renewable energy development. While everyone agrees that energy storage is the key component to enable widespread adoption of renewable energy sources, the development of a viable scalable technology has been missing. The Department of Energy has focused on expanded battery research and improved forecasting, and the utilities have deployed renewable energy resources only to the extent of satisfying Renewable Portfolio Standards. The lack of dispatchability of solar and wind-based electricity generation has drastically increased the cost of operation with these components. It is now clear that energy storage coupled with accurate solar and wind forecasting make up the only combination that can succeed in dispatchable renewable energy resources. Conventional batteries scale linearly in size, so the price becomes a barrier for large systems. Flow batteries scale sub-linearly and promise to be useful if their performance can be shown to provide sufficient support for solar and wind-base electricity generation resources. Compressed air energy storage provides the most desirable answer in terms of scalability and performance in all areas except efficiency. With the support of the DOE, Tucson Electric Power and Science Foundation Arizona, the Arizona Research Institute for Solar Energy (AzRISE) at the University of Arizona has had the opportunity to investigate CAES as a potential energy storage resource.

  17. Efficient energy storage in liquid desiccant cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    Hublitz, Astrid

    2008-07-18

    Liquid Desiccant Cooling Systems (LDCS) are open loop sorption systems for air conditioning that use a liquid desiccant such as a concentrated salt solution to dehumidify the outside air and cool it by evaporative cooling. Thermochemical energy storage in the concentrated liquid desiccant can bridge power mismatches between demand and supply. Low-flow LDCS provide high energy storage capacities but are not a state-of-the-art technology yet. The key challenge remains the uniform distribution of the liquid desiccant on the heat and mass transfer surfaces. The present research analyzes the factors of influence on the energy storage capacity by simulation of the heat and mass transfer processes and specifies performance goals for the distribution of the process media. Consequently, a distribution device for the liquid desiccant is developed that reliably meets the performance goals. (orig.)

  18. Efficiency of Compressed Air Energy Storage

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Brix, Wiebke

    2011-01-01

    The simplest type of a Compressed Air Energy Storage (CAES) facility would be an adiabatic process consisting only of a compressor, a storage and a turbine, compressing air into a container when storing and expanding when producing. This type of CAES would be adiabatic and would if the machines...

  19. Energy storage technologies;Technologies du stockage d'energie

    Energy Technology Data Exchange (ETDEWEB)

    Brunet, Y.

    2009-07-01

    This book takes stock of the advantages and drawbacks of the different energy storage solutions apart from the classical fossil fuels (oil, uranium, gas), and details the technologies developed for an electric end-use. Storage is one of the most critical point for the development of new energy technologies, in particular those that use the electricity vector all along the energy source chain (generation, production, transport, utilisation). Storage is important not only for individual or independent applications, that use renewable energies or not, often intermittent, but also to secure coupled systems like power transportation and distribution systems. The development and choice of the most relevant technologies is dependent of technical-economical parameters. It can also supply new services, in particular in the framework of new electricity markets. Content: power film-capacitors, magnetic storage, kinetic energy storage, compressed air energy storage (CAES), hydro-pneumatic storage, high-temperature thermal storage of electricity, hydraulic gravity storage, power electronic systems for energy storage. (J.S.)

  20. Energy storage on board of railway vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, M.; Scholten, J. [Bombardier Transportation, Mannheim (Germany)

    2004-07-01

    The proposed energy storage on board of a Railway vehicle leads to a big step in the reduction of consumed energy. Up to 30% energy saving are expected in a light rail vehicle, at the same time reducing the peak power demand drastically. In addition, with the energy storage an operation without catenary could become reality, which was successfully demonstrated with the prototype light rail vehicle driving with switched off pantograph. This prototype vehicle is in passenger operation since September 2003, the implemented software is optimised on energy savings and first experience is very promising. (authors)

  1. Energy Storage Applications in Power Systems with Renewable Energy Generation

    Science.gov (United States)

    Ghofrani, Mahmoud

    In this dissertation, we propose new operational and planning methodologies for power systems with renewable energy sources. A probabilistic optimal power flow (POPF) is developed to model wind power variations and evaluate the power system operation with intermittent renewable energy generation. The methodology is used to calculate the operating and ramping reserves that are required to compensate for power system uncertainties. Distributed wind generation is introduced as an operational scheme to take advantage of the spatial diversity of renewable energy resources and reduce wind power fluctuations using low or uncorrelated wind farms. The POPF is demonstrated using the IEEE 24-bus system where the proposed operational scheme reduces the operating and ramping reserve requirements and operation and congestion cost of the system as compared to operational practices available in the literature. A stochastic operational-planning framework is also proposed to adequately size, optimally place and schedule storage units within power systems with high wind penetrations. The method is used for different applications of energy storage systems for renewable energy integration. These applications include market-based opportunities such as renewable energy time-shift, renewable capacity firming, and transmission and distribution upgrade deferral in the form of revenue or reduced cost and storage-related societal benefits such as integration of more renewables, reduced emissions and improved utilization of grid assets. A power-pool model which incorporates the one-sided auction market into POPF is developed. The model considers storage units as market participants submitting hourly price bids in the form of marginal costs. This provides an accurate market-clearing process as compared to the 'price-taker' analysis available in the literature where the effects of large-scale storage units on the market-clearing prices are neglected. Different case studies are provided to

  2. Comparing energy storage options for renewable energy integration

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    -inclusive 100% renewable energy scenario developed for the Danish city Aalborg based on wind power, bio-resources and low-temperature geothermal heat. The paper investigates the system impact of different types of energy storage systems including district heating storage, biogas storage and electricity storage......Increasing penetrations of fluctuating energy sources for electricity generation, heating, cooling and transportation increase the need for flexibility of the energy system to accommodate the fluctuations of these energy sources. Controlling production, controlling demand and utilizing storage...... options are the three general categories of measures that may be applied for ensuring balance between production and demand, however with fluctuating energy sources, options are limited, and flexible demand has also demonstrated limited perspective. This paper takes its point of departure in an all...

  3. Solar Energy Storage and Distribution in Bole Stage of Chinese Fir Plantation%杉木林杆材阶段能量积累和分配的研究

    Institute of Scientific and Technical Information of China (English)

    康文星; 田大伦; 闫文德; 方晰

    2004-01-01

    The solar energy fixation, storage and distribution of the Chinese Fir plantation in Huitong located Ecology Station of Hunan Province were studied. The results showed that the ability of fixing solar energy in center area for Chinese Fir plantationwas 12 474×108-31943×108J·hm-2 , and the energy fixed by Chinese Fir plantation regularly decreased with the increasing of stand density. The distribution ratio of solar energy in stand was in order as : needle < twig < root < trunk. In evenaged forest,the reason of energy decrease with the increasing of forest density was the decrease of the solar energy accumulations of trunk,while the solar energy accumulation of twig and needle kept stably. When the forest was fully crowned, the ability of fixing solar energy decreased with the increasing of forest ages. The ability of photosynthesis decreased more quickly when the forest density was larger. When the forest density was 3 550·hm-2 the distribution ratio of solar energy in needle was the highest at the 14th year forest, while in the 16th year forest the distribution ratio in bark was 1.91 times of that of trunk, which meant that the trunk stopped growing and the forest was on the wane. When the accessibility entering the pole stage, the forest density was the main factor which affected the solar energy fixation. Proper intermidiate was a necessary means to increase the ability of photosynthesis.

  4. Energy Storage (II): Developing Advanced Technologies

    Science.gov (United States)

    Robinson, Arthur L

    1974-01-01

    Energy storage, considered by some scientists to be the best technological and economic advancement after advanced nuclear power, still rates only modest funding for research concerning the development of advanced technologies. (PEB)

  5. Demand Response and Energy Storage Integration Study

    Energy Technology Data Exchange (ETDEWEB)

    Ookie Ma, Kerry Cheung

    2016-03-01

    Demand response and energy storage resources present potentially important sources of bulk power system services that can aid in integrating variable renewable generation. While renewable integration studies have evaluated many of the challenges associated with deploying large amounts of variable wind and solar generation technologies, integration analyses have not yet fully incorporated demand response and energy storage resources. This report represents an initial effort in analyzing the potential integration value of demand response and energy storage, focusing on the western United States. It evaluates two major aspects of increased deployment of demand response and energy storage: (1) Their operational value in providing bulk power system services and (2) Market and regulatory issues, including potential barriers to deployment.

  6. Value of Energy Storage for Grid Applications

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, P.; Jorgenson, J.; Hummon, M.; Jenkin, T.; Palchak, D.; Kirby, B.; Ma, O.; O' Malley, M.

    2013-05-01

    This analysis evaluates several operational benefits of electricity storage, including load-leveling, spinning contingency reserves, and regulation reserves. Storage devices were simulated in a utility system in the western United States, and the operational costs of generation was compared to the same system without the added storage. This operational value of storage was estimated for devices of various sizes, providing different services, and with several sensitivities to fuel price and other factors. Overall, the results followed previous analyses that demonstrate relatively low value for load-leveling but greater value for provision of reserve services. The value was estimated by taking the difference in operational costs between cases with and without energy storage and represents the operational cost savings from deploying storage by a traditional vertically integrated utility. The analysis also estimated the potential revenues derived from a merchant storage plant in a restructured market, based on marginal system prices. Due to suppression of on-/off-peak price differentials and incomplete capture of system benefits (such as the cost of power plant starts), the revenue obtained by storage in a market setting appears to be substantially less than the net benefit provided to the system. This demonstrates some of the additional challenges for storage deployed in restructured energy markets.

  7. DEM - distribution energy management

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A.; Kekkonen, V.; Koreneff, G. [VTT Energy, Espoo (Finland)] [and others

    1998-08-01

    The electricity market was de-regulated in Finland at the end of 1995 and the customers can now freely choose their power suppliers. The national grid and local distribution network operators are now separated from the energy business. The network operators transmit the electric power to the customers on equal terms regardless from whom the power is purchased. The Finnish national grid is owned by one company Finnish Power Grid PLC (Fingrid). The major shareholders of Fingrid are the state of Finland, two major power companies and institutional investors. In addition there are about 100 local distribution utilities operating the local 110 kV, 20 kV and 0.4 kV networks. The distribution utilities are mostly owned by the municipalities and towns. In each network one energy supplier is always responsible for the hourly energy balance in the network (a `host`) and it also has the obligation to provide public energy prices accessible to any customer in the network`s area. The Finnish regulating authorities nominate such a supplier who has a dominant market share in the network`s area as the supplier responsible for the network`s energy balance. A regulating authority, called the Electricity Market Centre, ensures that the market is operating properly. The transmission prices and public energy prices are under the Electricity Market Centre`s control. For domestic and other small customers the cost of hourly metering (ca. 1000 US$) would be prohibitive and therefore the use of conventional energy metering and load models is under consideration by the authorities. Small customer trade with the load models (instead of the hourly energy recording) is scheduled to start in the first half of 1998. In this presentation, the problems of energy management from the standpoint of the energy trading and distributing companies in the new situation are first discussed. The topics covered are: the hourly load data management, the forecasting and estimation of hourly energy demands

  8. Review of Magnetic Flywheel Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    Prince Owusu-Ansah

    2014-08-01

    Full Text Available This study studies an overview of magnetic flywheel energy storage system. Energy storage is an integral part of any critical power system, as this stored energy is used to offset interruptions in the power delivered system from either a utility or an on-site generator. Magnetic flywheel as mechanical batteries using composite rotor, magnetic support bearings as well as power electronics to store electrical energy to replace stone wheel and chemical batteries has resulted in high power and energy densities. Traditionally, capacitors are used for short term storage (µs-ms and filtering, chemical batteries are used for intermediate storage (min-h and diesel fuel is used for long-term storage (h-days. Electricity generated from renewable sources, which has shown remarkable growth worldwide, can rarely provide immediate response to demand as these sources do not deliver regular supply easily adjustable to consumption needs. Thus, the growth of this decentralization production means greater network load stability problems and requires energy storage, generally using lead acid batteries as a potential solution. Finally the integration of all subsystems optimally of the magnetic flywheel system has resulted in a mechanical battery which can supply more efficient, reliable and uninterrupted power to meet the ever increasing demand of industrial machinery and automobiles.

  9. Compressed air energy storage technology program

    Science.gov (United States)

    Loscutoff, W. V.

    1980-06-01

    Progress in the development of compressed air energy storage (CAES) technologies for central station electric utility applications is reported. It is reported that the concept improves the effectiveness of a gas turbine using petroleum fuels, could reduce petroleum fuel consumption of electric utility peaking plants, and is technically feasible and economically viable. Specific topics discussed include stability criteria for large underground reservoirs in salt domes, hard rock, and porous rock used for air storage in utility applications and second-generation technologies that have minimal or no dependence on petroleum fuels. The latter includes integration of thermal energy storage, fluidized bed combustion, or coal gasification with CAES.

  10. Seasonal energy storage - PV-hydrogen systems

    Energy Technology Data Exchange (ETDEWEB)

    Leppaenen, J. [Neste Oy/NAPS (Finland)

    1998-10-01

    PV systems are widely used in remote areas e.g. in telecommunication systems. Typically lead acid batteries are used as energy storage. In northern locations seasonal storage is needed, which however is too expensive and difficult to realise with batteries. Therefore, a PV- battery system with a diesel backup is sometimes used. The disadvantages of this kind of system for very remote applications are the need of maintenance and the need to supply the fuel. To overcome these problems, it has been suggested to use hydrogen technologies to make a closed loop autonomous energy storage system

  11. Solar energy thermalization and storage device

    Science.gov (United States)

    McClelland, J.F.

    A passive solar thermalization and thermal energy storage assembly which is visually transparent is described. The assembly consists of two substantial parallel, transparent wall members mounted in a rectangular support frame to form a liquid-tight chamber. A semitransparent thermalization plate is located in the chamber, substantially paralled to and about equidistant from the transparent wall members to thermalize solar radiation which is stored in a transparent thermal energy storage liquid which fills the chamber. A number of the devices, as modules, can be stacked together to construct a visually transparent, thermal storage wall for passive solar-heated buildings.

  12. Regenesys utility scale energy storage. Network performance benefits of energy storage for a large wind farm

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This report considers the potential weakness of distributed systems at the locations where it is most suited for the connection of renewable energy sources such as wind farms. The current use of deep charging where the new generator is charged for any network reinforcement required for the new connection onto the UK distribution networks is explained along with the way in which connection costs are mainly determined by peak generation output. The use of on-site energy storage to reduce peak generation output onto the network, the effect of the minimum and maximum voltage limits on the connection capacity of the wind farms, and the impact of wind farms on the local voltage profile are discussed. A voltage controller that potentially allows increased connection of wind farm capacity is proposed.

  13. Bioinspired fractal electrodes for solar energy storages.

    Science.gov (United States)

    Thekkekara, Litty V; Gu, Min

    2017-03-31

    Solar energy storage is an emerging technology which can promote the solar energy as the primary source of electricity. Recent development of laser scribed graphene electrodes exhibiting a high electrical conductivity have enabled a green technology platform for supercapacitor-based energy storage, resulting in cost-effective, environment-friendly features, and consequent readiness for on-chip integration. Due to the limitation of the ion-accessible active porous surface area, the energy densities of these supercapacitors are restricted below ~3 × 10(-3) Whcm(-3). In this paper, we demonstrate a new design of biomimetic laser scribed graphene electrodes for solar energy storage, which embraces the structure of Fern leaves characterized by the geometric family of space filling curves of fractals. This new conceptual design removes the limit of the conventional planar supercapacitors by significantly increasing the ratio of active surface area to volume of the new electrodes and reducing the electrolyte ionic path. The attained energy density is thus significantly increased to ~10(-1) Whcm(-3)- more than 30 times higher than that achievable by the planar electrodes with ~95% coulombic efficiency of the solar energy storage. The energy storages with these novel electrodes open the prospects of efficient self-powered and solar-powered wearable, flexible and portable applications.

  14. Bioinspired fractal electrodes for solar energy storages

    Science.gov (United States)

    Thekkekara, Litty V.; Gu, Min

    2017-03-01

    Solar energy storage is an emerging technology which can promote the solar energy as the primary source of electricity. Recent development of laser scribed graphene electrodes exhibiting a high electrical conductivity have enabled a green technology platform for supercapacitor-based energy storage, resulting in cost-effective, environment-friendly features, and consequent readiness for on-chip integration. Due to the limitation of the ion-accessible active porous surface area, the energy densities of these supercapacitors are restricted below ~3 × 10-3 Whcm-3. In this paper, we demonstrate a new design of biomimetic laser scribed graphene electrodes for solar energy storage, which embraces the structure of Fern leaves characterized by the geometric family of space filling curves of fractals. This new conceptual design removes the limit of the conventional planar supercapacitors by significantly increasing the ratio of active surface area to volume of the new electrodes and reducing the electrolyte ionic path. The attained energy density is thus significantly increased to ~10-1 Whcm-3- more than 30 times higher than that achievable by the planar electrodes with ~95% coulombic efficiency of the solar energy storage. The energy storages with these novel electrodes open the prospects of efficient self-powered and solar-powered wearable, flexible and portable applications.

  15. Bioinspired fractal electrodes for solar energy storages

    Science.gov (United States)

    Thekkekara, Litty V.; Gu, Min

    2017-01-01

    Solar energy storage is an emerging technology which can promote the solar energy as the primary source of electricity. Recent development of laser scribed graphene electrodes exhibiting a high electrical conductivity have enabled a green technology platform for supercapacitor-based energy storage, resulting in cost-effective, environment-friendly features, and consequent readiness for on-chip integration. Due to the limitation of the ion-accessible active porous surface area, the energy densities of these supercapacitors are restricted below ~3 × 10−3 Whcm−3. In this paper, we demonstrate a new design of biomimetic laser scribed graphene electrodes for solar energy storage, which embraces the structure of Fern leaves characterized by the geometric family of space filling curves of fractals. This new conceptual design removes the limit of the conventional planar supercapacitors by significantly increasing the ratio of active surface area to volume of the new electrodes and reducing the electrolyte ionic path. The attained energy density is thus significantly increased to ~10−1 Whcm−3- more than 30 times higher than that achievable by the planar electrodes with ~95% coulombic efficiency of the solar energy storage. The energy storages with these novel electrodes open the prospects of efficient self-powered and solar-powered wearable, flexible and portable applications. PMID:28361924

  16. Energy optimization for a wind DFIG with flywheel energy storage

    Science.gov (United States)

    Hamzaoui, Ihssen; Bouchafaa, Farid

    2016-07-01

    The type of distributed generation unit that is the subject of this paper relates to renewable energy sources, especially wind power. The wind generator used is based on a double fed induction Generator (DFIG). The stator of the DFIG is connected directly to the network and the rotor is connected to the network through the power converter with three levels. The objective of this work is to study the association a Flywheel Energy Storage System (FESS) in wind generator. This system is used to improve the quality of electricity provided by wind generator. It is composed of a flywheel; an induction machine (IM) and a power electronic converter. A maximum power tracking technique « Maximum Power Point Tracking » (MPPT) and a strategy for controlling the pitch angle is presented. The model of the complete system is developed in Matlab/Simulink environment / to analyze the results from simulation the integration of wind chain to networks.

  17. Energy optimization for a wind DFIG with flywheel energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Hamzaoui, Ihssen, E-mail: hamzaoui-ihssen2000@yahoo.fr [Laboratory of Instrumentation, Faculty of Electronics and Computer, University of Sciences and Technology Houari Boumediene, BP 32 El-Alia 16111 Bab-Ezzouar (Algeria); Laboratory of Instrumentation, Faculty of Electronics and Computer, University of Khemis Miliana, Ain Defla (Algeria); Bouchafaa, Farid, E-mail: fbouchafa@gmail.com [Laboratory of Instrumentation, Faculty of Electronics and Computer, University of Sciences and Technology Houari Boumediene, BP 32 El-Alia 16111 Bab-Ezzouar (Algeria)

    2016-07-25

    The type of distributed generation unit that is the subject of this paper relates to renewable energy sources, especially wind power. The wind generator used is based on a double fed induction Generator (DFIG). The stator of the DFIG is connected directly to the network and the rotor is connected to the network through the power converter with three levels. The objective of this work is to study the association a Flywheel Energy Storage System (FESS) in wind generator. This system is used to improve the quality of electricity provided by wind generator. It is composed of a flywheel; an induction machine (IM) and a power electronic converter. A maximum power tracking technique « Maximum Power Point Tracking » (MPPT) and a strategy for controlling the pitch angle is presented. The model of the complete system is developed in Matlab/Simulink environment / to analyze the results from simulation the integration of wind chain to networks.

  18. Twelve Principles for Green Energy Storage in Grid Applications.

    Science.gov (United States)

    Arbabzadeh, Maryam; Johnson, Jeremiah X; Keoleian, Gregory A; Rasmussen, Paul G; Thompson, Levi T

    2016-01-19

    The introduction of energy storage technologies to the grid could enable greater integration of renewables, improve system resilience and reliability, and offer cost effective alternatives to transmission and distribution upgrades. The integration of energy storage systems into the electrical grid can lead to different environmental outcomes based on the grid application, the existing generation mix, and the demand. Given this complexity, a framework is needed to systematically inform design and technology selection about the environmental impacts that emerge when considering energy storage options to improve sustainability performance of the grid. To achieve this, 12 fundamental principles specific to the design and grid application of energy storage systems are developed to inform policy makers, designers, and operators. The principles are grouped into three categories: (1) system integration for grid applications, (2) the maintenance and operation of energy storage, and (3) the design of energy storage systems. We illustrate the application of each principle through examples published in the academic literature, illustrative calculations, and a case study with an off-grid application of vanadium redox flow batteries (VRFBs). In addition, trade-offs that can emerge between principles are highlighted.

  19. Flywheel energy storage using superconducting magnetic bearings

    Science.gov (United States)

    Abboud, R. G.; Uherka, K.; Hull, J.; Mulcahy, T.

    Storage of electrical energy on a utility scale is currently not practicable for most utilities, preventing the full utilization of existing base-load capacity. A potential solution to this problem is Flywheel Energy Storage (FES), made possible by technological developments in high-temperature superconducting materials. Commonwealth Research Corporation (CRC), the research arm of Commonwealth Edison Company, and Argonne National Laboratory are implementing a demonstration project to advance the state of the art in high temperature superconductor (HTS) bearing performance and the overall demonstration of efficient Flywheel Energy Storage. Currently, electricity must be used simultaneously with its generation as electrical energy storage is not available for most utilities. Existing storage methods either are dependent on special geography, are too expensive, or are too inefficient. Without energy storage, electric utilities, such as Commonwealth Edison Company, are forced to cycle base load power plants to meet load swings in hourly customer demand. Demand can change by as much as 30% over a 12-hour period and result in significant costs to utilities as power plant output is adjusted to meet these changes. HTS FES systems can reduce demand-based power plant cycling by storing unused nighttime capacity until it is needed to meet daytime demand.

  20. Energy storage systems - Characteristics and comparisons

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, H. [Wind Energy Research Laboratory (WERL), Universite du Quebec a Rimouski, 300 allee des Ursulines, Que. (Canada); Anti Icing Materials International Laboratory (AMIL), Universite du Quebec a Chicoutimi, 555 boulevard de l' Universite, Que. (Canada); Ilinca, A. [Wind Energy Research Laboratory (WERL), Universite du Quebec a Rimouski, 300 allee des Ursulines, Que. (Canada); Perron, J. [Anti Icing Materials International Laboratory (AMIL), Universite du Quebec a Chicoutimi, 555 boulevard de l' Universite, Que. (Canada)

    2008-06-15

    Electricity generated from renewable sources, which has shown remarkable growth worldwide, can rarely provide immediate response to demand as these sources do not deliver a regular supply easily adjustable to consumption needs. Thus, the growth of this decentralized production means greater network load stability problems and requires energy storage, generally using lead batteries, as a potential solution. However, lead batteries cannot withstand high cycling rates, nor can they store large amounts of energy in a small volume. That is why other types of storage technologies are being developed and implemented. This has led to the emergence of storage as a crucial element in the management of energy from renewable sources, allowing energy to be released into the grid during peak hours when it is more valuable. The work described in this paper highlights the need to store energy in order to strengthen power networks and maintain load levels. There are various types of storage methods, some of which are already in use, while others are still in development. We have taken a look at the main characteristics of the different electricity storage techniques and their field of application (permanent or portable, long- or short-term storage, maximum power required, etc.). These characteristics will serve to make comparisons in order to determine the most appropriate technique for each type of application. (author)

  1. Kauai Island Utility Cooperative energy storage study.

    Energy Technology Data Exchange (ETDEWEB)

    Akhil, Abbas Ali; Yamane, Mike (Kauai Island Utility Cooperative, Lihu' e, HI); Murray, Aaron T.

    2009-06-01

    Sandia National Laboratories performed an assessment of the benefits of energy storage for the Kauai Island Utility Cooperative. This report documents the methodology and results of this study from a generation and production-side benefits perspective only. The KIUC energy storage study focused on the economic impact of using energy storage to shave the system peak, which reduces generator run time and consequently reduces fuel and operation and maintenance (O&M) costs. It was determined that a 16-MWh energy storage system would suit KIUC's needs, taking into account the size of the 13 individual generation units in the KIUC system and a system peak of 78 MW. The analysis shows that an energy storage system substantially reduces the run time of Units D1, D2, D3, and D5 - the four smallest and oldest diesel generators at the Port Allen generating plant. The availability of stored energy also evens the diurnal variability of the remaining generation units during the off- and on-peak periods. However, the net economic benefit is insufficient to justify a load-leveling type of energy storage system at this time. While the presence of storage helps reduce the run time of the smaller and older units, the economic dispatch changes and the largest most efficient unit in the KIUC system, the 27.5-MW steam-injected combustion turbine at Kapaia, is run for extra hours to provide the recharge energy for the storage system. The economic benefits of the storage is significantly reduced because the charging energy for the storage is derived from the same fuel source as the peak generation source it displaces. This situation would be substantially different if there were a renewable energy source available to charge the storage. Especially, if there is a wind generation resource introduced in the KIUC system, there may be a potential of capturing the load-leveling benefits as well as using the storage to dampen the dynamic instability that the wind generation could introduce

  2. Energy storage systems cost update : a study for the DOE Energy Storage Systems Program.

    Energy Technology Data Exchange (ETDEWEB)

    Schoenung, Susan M. (Longitude 122 West, Menlo Park, CA)

    2011-04-01

    This paper reports the methodology for calculating present worth of system and operating costs for a number of energy storage technologies for representative electric utility applications. The values are an update from earlier reports, categorized by application use parameters. This work presents an update of energy storage system costs assessed previously and separately by the U.S. Department of Energy (DOE) Energy Storage Systems Program. The primary objective of the series of studies has been to express electricity storage benefits and costs using consistent assumptions, so that helpful benefit/cost comparisons can be made. Costs of energy storage systems depend not only on the type of technology, but also on the planned operation and especially the hours of storage needed. Calculating the present worth of life-cycle costs makes it possible to compare benefit values estimated on the same basis.

  3. Hydrogen-based electrochemical energy storage

    Science.gov (United States)

    Simpson, Lin Jay

    2013-08-06

    An energy storage device (100) providing high storage densities via hydrogen storage. The device (100) includes a counter electrode (110), a storage electrode (130), and an ion conducting membrane (120) positioned between the counter electrode (110) and the storage electrode (130). The counter electrode (110) is formed of one or more materials with an affinity for hydrogen and includes an exchange matrix for elements/materials selected from the non-noble materials that have an affinity for hydrogen. The storage electrode (130) is loaded with hydrogen such as atomic or mono-hydrogen that is adsorbed by a hydrogen storage material such that the hydrogen (132, 134) may be stored with low chemical bonding. The hydrogen storage material is typically formed of a lightweight material such as carbon or boron with a network of passage-ways or intercalants for storing and conducting mono-hydrogen, protons, or the like. The hydrogen storage material may store at least ten percent by weight hydrogen (132, 134) at ambient temperature and pressure.

  4. Aquifer thermal energy storage. International symposium: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    Aquifers have been used to store large quantities of thermal energy to supply process cooling, space cooling, space heating, and ventilation air preheating, and can be used with or without heat pumps. Aquifers are used as energy sinks and sources when supply and demand for energy do not coincide. Aquifer thermal energy storage may be used on a short-term or long-term basis; as the sole source of energy or as a partial storage; at a temperature useful for direct application or needing upgrade. The sources of energy used for aquifer storage are ambient air, usually cold winter air; waste or by-product energy; and renewable energy such as solar. The present technical, financial and environmental status of ATES is promising. Numerous projects are operating and under development in several countries. These projects are listed and results from Canada and elsewhere are used to illustrate the present status of ATES. Technical obstacles have been addressed and have largely been overcome. Cold storage in aquifers can be seen as a standard design option in the near future as it presently is in some countries. The cost-effectiveness of aquifer thermal energy storage is based on the capital cost avoidance of conventional chilling equipment and energy savings. ATES is one of many developments in energy efficient building technology and its success depends on relating it to important building market and environmental trends. This paper attempts to provide guidance for the future implementation of ATES. Individual projects have been processed separately for entry onto the Department of Energy databases.

  5. Energy storage options for space power

    Science.gov (United States)

    Hoffman, H. W.; Martin, J. F.; Olszewski, M.

    Including energy storage in a space power supply enhances the feasibility of using thermal power cycles (Rankine or Brayton) and providing high-power pulses. Superconducting magnets, capacitors, electrochemical batteries, thermal phase-change materials (PCM), and flywheels are assessed; the results obtained suggest that flywheels and phase-change devices hold the most promise. Latent heat storage using inorganic salts and metallic eutectics offers thermal energy storage densities of 1500 kJ/kg to 2000 kJ/kg at temperatures to 1675 K. Innovative techniques allow these media to operate in direct contact with the heat engine working fluid. Enhancing thermal conductivity and/or modifying PCM crystallization habit provide other options. Flywheels of low-strain graphite and Kevlar fibers have achieved mechanical energy storage densities of 300 kJ/kg. With high-strain graphite fibers, storage densities appropriate to space power needs (about 500 kJ/kg) seem feasible. Coupling advanced flywheels with emerging high power density homopolar generators and compulsators could result in electric pulse-power storage modules of significantly higher energy density.

  6. Optimal Demand Response with Energy Storage Management

    OpenAIRE

    Huang, Longbo; Walrand, Jean; Ramchandran, Kannan

    2012-01-01

    In this paper, we consider the problem of optimal demand response and energy storage management for a power consuming entity. The entity's objective is to find an optimal control policy for deciding how much load to consume, how much power to purchase from/sell to the power grid, and how to use the finite capacity energy storage device and renewable energy, to minimize his average cost, being the disutility due to load- shedding and cost for purchasing power. Due to the coupling effect of the...

  7. Polymers for energy storage and conversion

    CERN Document Server

    Mittal, Vikas

    2013-01-01

    One of the first comprehensive books to focus on the role of polymers in the burgeoning energy materials market Polymers are increasingly finding applications in the areas of energy storage and conversion. A number of recent advances in the control of the polymer molecular structure which allows the polymer properties to be more finely tuned have led to these advances and new applications. Polymers for Energy Storage and Conversion assimilates these advances in the form of a comprehensive text that includes the synthesis and properties of a large number of polymer systems for

  8. Reaction wheels for kinetic energy storage

    Science.gov (United States)

    Studer, P. A.

    1984-01-01

    In contrast to all existing reaction wheel implementations, an order of magnitude increase in speed can be obtained efficiently if power to the actuators can be recovered. This allows a combined attitude control-energy storage system to be developed with structure mounted reaction wheels. The feasibility of combining reaction wheels with energy storage wwheels is demonstrated. The power required for control torques is a function of wheel speed but this energy is not dissipated; it is stored in the wheel. The I(2)R loss resulting from a given torque is shown to be constant, independent of the design speed of the motor. What remains, in order to efficiently use high speed wheels (essential for energy storage) for control purposes, is to reduce rotational losses to acceptable levels. Progress was made in permanent magnet motor design for high speed operation. Variable field motors offer more control flexibility and efficiency over a broader speed range.

  9. Energy storage: Redox Flow Batteries Go Organic

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei; Sprenkle, Vincent L.

    2016-02-19

    Access to sustainable and affordable energy is the foundation for the economic growth of our current society and its future prosperity. Energy harvested from renewable resources, such as solar and wind, although currently at a small fraction, is on a steady trajectory of increasing installation accompanied with falling cost. Driven also by the need to reduce the carbon footprint from electricity generation, they could provide a clean and sustainable energy future. The caveat, however, is the intermittent and fluctuating nature of the renewables, which threatens the stability of the grid when its share surpasses 20% of the overall energy capacity. 1 Besides the on-demand power generation, electrical energy storage is another potentially cost-effective way to provide massive energy storage for not only renewable energy integration, but to balance the mismatch between supply and demand, and the improvement of grid reliability and efficiency also.

  10. 支撑负荷价值最大化的孤岛有源配电网储能容量的配置%Capacity Allocation of Energy Storage Considering Maximization of Island Load Value in Active Distribution Network

    Institute of Scientific and Technical Information of China (English)

    魏炜; 陈嘉; 罗凤章

    2016-01-01

    In the distribution network island due to faults,in order to improve the power supply capability of intermit⁃tent power generation for important load,some energy storage system with reasonable power path for load is a solution. This paper proposes an optimal capacity allocation method for energy storage based on island searching strategy. The performance of traditional searching method is improved,which is employed to maximize the load value and obtain the sets of all best power paths in the island structure. In the capacity allocation of energy storage,this paper maximizes the power supply efficiency of energy storage by referring to the sets of best power paths. Moreover,the probability distribu⁃tion of load value supported by energy storage is also determined according to the power output duration curve. The sim⁃ulation example verifies that the proposed method can effectively determine the optimal energy storage capacity when the energy storage capacity per unit supports the maximum load value.%在配电网因故障出现的孤岛内,为提高间歇性电源对重要负荷的供电能力,配置一定容量的储能系统并选择合理的供电路径支撑负荷。该文提出了基于孤岛搜索的有源配电网储能容量优化配置方法。在孤岛搜索中对常规方法改进,求得孤岛拓扑约束下所有使得支撑负荷价值最大的供电路径集合,在储能容量优化配置中结合供电路径最大化储能支撑效果,依据电源出力持续曲线确定储能支撑负荷价值的概率分布。仿真算例验证所提方法能有效确定单位储能出力支撑负荷价值最大时的最佳储能容量。

  11. Hydrogen based energy storage for solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Vanhanen, J.; Hagstroem, M.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

    1998-10-01

    The main technical constraint in solar energy systems which operate around the year is the lack of suitable long-term energy storage. Conventional solutions to overcome the problem of seasonal storage in PV power systems are to use oversized batteries as a seasonal energy storage, or to use a diesel back-up generator. However, affordable lead-acid batteries are not very suitable for seasonal energy storage because of a high self-discharge rate and enhanced deterioration and divergence of the single cells during prolonged periods of low state of charge in times of low irradiation. These disadvantages can be avoided by a back-up system, e.g. a diesel generator, which car supply energy to the loads and charge the battery to the full state of charge to avoid the above mentioned disadvantages. Unfortunately, diesel generators have several disadvantages, e.g. poor starting reliability, frequent need for maintenance and noise

  12. An energy storage and regeneration system

    DEFF Research Database (Denmark)

    2006-01-01

    caverns. When the energy demand exceeds the power production capacity of the plant, the stored gases are burned and the thermal energy is converted into electricity in gas turbine generators. The regenerated electrical power is then used to supplement the output of the electric power plant to meet......  The present invention relates to a method and a system for storing excess energy produced by an electric power plant during periods of lower energy demand than the power plant production capacity. The excess energy is stored by hydrolysis of water and storage of hydrogen and oxygen in underground...... the higher level of energy demand....

  13. Frontiers of Energy Storage and Conversion

    Directory of Open Access Journals (Sweden)

    Jiajun Chen

    2014-09-01

    Full Text Available This special issue of Inorganics features a Forum for novel materials and approaches for electrochemical energy storage and conversion. Diminishing non-renewable fossil fuels and the resulting unattainability of environment have made us search new sustainable energy resources and develop technology for efficient utilization of such resources. Green energy sources, such as solar, hydroelectric, thermal and wind energy are partially replacing fossil fuels as means to generate power. Inorganic (solid state materials are key in the development of advanced devices for the efficient storage and conversion of energy. The grand challenge facing the inorganic chemist is to discover, design rationally and utilize advanced technological materials made from earth-abound elements for these energy storage and conversion processes. Recent spectacular progress in inorganic materials synthesis, characterization, and computational screening has greatly advanced this field, which drove us to edit this issue to provide a window to view the development of this field for the community. This special issue comprises research articles, which highlights some of the most recent advances in new materials for energy storage and conversion. [...

  14. Progress in electrical energy storage system:A critical review

    Institute of Scientific and Technical Information of China (English)

    Haisheng Chen; Thang Ngoc Cong; Wei Yang; Chunqing Tan; Yongliang Li; Yulong Ding

    2009-01-01

    Electrical energy storage technologies for stationary applications are reviewed.Particular attention is paid to pumped hydroelectric storage,compressed air energy storage,battery,flow battery,fuel cell,solar fuel,superconducting magnetic energy storage, flywheel, capacitor/supercapacitor,and thermal energy torage.Comparison is made among these technologies in terms of technical characteris-tics,applications and deployment status.

  15. Adiabatic Liquid Piston Compressed Air Energy Storage

    OpenAIRE

    Petersen, Tage; Elmegaard, Brian; Pedersen, Allan Schrøder

    2013-01-01

    This project investigates the potential of a Compressed Air Energy Storage system (CAES system). CAES systems are used to store mechanical energy in the form of compressed air. The systems use electricity to drive the compressor at times of low electricity demand with the purpose of converting the mechanical energy into electricity at times of high electricity demand. Two such systems are currently in operation; one in Germany (Huntorf) and one in the USA (Macintosh, Alabama). In both cases, ...

  16. Future possibilities for energy-storage automobiles

    Energy Technology Data Exchange (ETDEWEB)

    O' Connell, L.G.

    1981-04-23

    Because of the potential threat of a future petroleum shortage, there is increased interest in developing alternative propulsion systems for automobiles, systems that will allow the nation to reduce its demand for petroleum by this part of the transportation sector. A four-year study which assessed the future of energy storage devices for use in automobile propulsion systems has been completed. Results of the energy storage device evaluation are presented. This includes projections of future device characteristics. In addition, the results of the propulsion system analysis are given. Future energy storage automobiles were conceptually designed and they are compared to each other and the baseline internal combustion engine vehicle for several levels of performance.

  17. Development of an energy storage tank model

    Science.gov (United States)

    Buckley, Robert Christopher

    A linearized, one-dimensional finite difference model employing an implicit finite difference method for energy storage tanks is developed, programmed with MATLAB, and demonstrated for different applications. A set of nodal energy equations is developed by considering the energy interactions on a small control volume. The general method of solving these equations is described as are other features of the simulation program. Two modeling applications are presented: the first using a hot water storage tank with a solar collector and an absorption chiller to cool a building in the summer, the second using a molten salt storage system with a solar collector and steam power plant to generate electricity. Recommendations for further study as well as all of the source code generated in the project are also provided.

  18. Engineered nanomembranes for smart energy storage devices.

    Science.gov (United States)

    Wang, Xianfu; Chen, Yu; Schmidt, Oliver G; Yan, Chenglin

    2016-03-07

    Engineered nanomembranes are of great interest not only for large-scale energy storage devices, but also for on-chip energy storage integrated microdevices (such as microbatteries, microsupercapacitors, on-chip capacitors, etc.) because of their large active surfaces for electrochemical reactions, shortened paths for fast ion diffusion, and easy engineering for microdevice applications. In addition, engineered nanomembranes provide a lab-on-chip electrochemical device platform for probing the correlations of electrode structure, electrical/ionic conductivity, and electrochemical kinetics with device performance. This review focuses on the recent progress in engineered nanomembranes including tubular nanomembranes and planar nanomembranes, with the aim to provide a systematic summary of their fabrication, modification, and energy storage applications in lithium-ion batteries, lithium-oxygen batteries, on-chip electrostatic capacitors and micro-supercapacitors. A comprehensive understanding of the relationship between engineered nanomembranes and electrochemical properties of lithium ion storage with engineered single-tube microbatteries is given, and the flexibility and transparency of micro-supercapacitors is also discussed. Remarks on challenges and perspectives related to engineered nanomembranes for the further development of energy storage applications conclude this review.

  19. Electroactive graphene nanofluids for fast energy storage

    Science.gov (United States)

    Dubal, Deepak P.; Gomez-Romero, Pedro

    2016-09-01

    Graphenes have been extensively studied as electrode materials for energy storage in supercapacitors and batteries, but always as solid electrodes. The conception and development of graphene electroactive nanofluids (ENFs) reported here for the first time provides a novel way to ‘form’ graphene electrodes and demonstrates proof of concept for the use of these liquid electrodes for energy storage in novel flow cells. A stabilized dispersion of reduced graphene oxide (rGO) in aqueous sulfuric acid solution was shown to have capacitive energy storage capabilities parallel to those of solid electrode supercapacitors (169 F g-1(rGO)) but working up to much faster rates (from 1 mV s-1 to the highest scan rate of 10 V s-1) in nanofluids with 0.025, 0.1 and 0.4 wt% rGO, featuring viscosities very close to that of water, thus being perfectly suitable for scalable flow cells. Our results provide proof of concept for this technology and include preliminary flow cell performance of rGO nanofluids under static and continuous flow conditions. Graphene nanofluids effectively behave as true liquid electrodes with very fast capacitive storage mechanism and herald the application not only of graphenes but also other 2D materials like MoS2 in nanofluids for energy storage and beyond.

  20. Optimal Demand Response with Energy Storage Management

    CERN Document Server

    Huang, Longbo; Ramchandran, Kannan

    2012-01-01

    In this paper, we consider the problem of optimal demand response and energy storage management for a power consuming entity. The entity's objective is to find an optimal control policy for deciding how much load to consume, how much power to purchase from/sell to the power grid, and how to use the finite capacity energy storage device and renewable energy, to minimize his average cost, being the disutility due to load- shedding and cost for purchasing power. Due to the coupling effect of the finite size energy storage, such problems are challenging and are typically tackled using dynamic programming, which is often complex in computation and requires substantial statistical information of the system dynamics. We instead develop a low-complexity algorithm called Demand Response with Energy Storage Management (DR-ESM). DR-ESM does not require any statistical knowledge of the system dynamics, including the renewable energy and the power prices. It only requires the entity to solve a small convex optimization pr...

  1. Increased use of solar energy in commercial buildings by integrating energy storage.

    OpenAIRE

    Nilsson, Nina

    2016-01-01

    From a comparison of available thermal energy storage (TES) technologies it can be concluded that the most mature and suitable storage methods for modern commercial buildings in Sweden are storage tanks, either for heat or cold energy, and underground storage solutions such as borehole thermal energy storage (BTES), aquifer storage and energy piles. In this study an integrated solar energy storage system for heating purpose has been designed with BTES, hot water storage tank(s) and solar ther...

  2. Optimal Power Management Strategy for Energy Storage with Stochastic Loads

    Directory of Open Access Journals (Sweden)

    Stefano Pietrosanti

    2016-03-01

    Full Text Available In this paper, a power management strategy (PMS has been developed for the control of energy storage in a system subjected to loads of random duration. The PMS minimises the costs associated with the energy consumption of specific systems powered by a primary energy source and equipped with energy storage, under the assumption that the statistical distribution of load durations is known. By including the variability of the load in the cost function, it was possible to define the optimality criteria for the power flow of the storage. Numerical calculations have been performed obtaining the control strategies associated with the global minimum in energy costs, for a wide range of initial conditions of the system. The results of the calculations have been tested on a MATLAB/Simulink model of a rubber tyre gantry (RTG crane equipped with a flywheel energy storage system (FESS and subjected to a test cycle, which corresponds to the real operation of a crane in the Port of Felixstowe. The results of the model show increased energy savings and reduced peak power demand with respect to existing control strategies, indicating considerable potential savings for port operators in terms of energy and maintenance costs.

  3. Aquifer thermal energy (heat and chill) storage

    Energy Technology Data Exchange (ETDEWEB)

    Jenne, E.A. (ed.)

    1992-11-01

    As part of the 1992 Intersociety Conversion Engineering Conference, held in San Diego, California, August 3--7, 1992, the Seasonal Thermal Energy Storage Program coordinated five sessions dealing specifically with aquifer thermal energy storage technologies (ATES). Researchers from Sweden, The Netherlands, Germany, Switzerland, Denmark, Canada, and the United States presented papers on a variety of ATES related topics. With special permission from the Society of Automotive Engineers, host society for the 1992 IECEC, these papers are being republished here as a standalone summary of ATES technology status. Individual papers are indexed separately.

  4. Underground-Energy-Storage Program, 1982 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Kannberg, L.D.

    1983-06-01

    Two principal underground energy storage technologies are discussed--Seasonal Thermal Energy Storage (STES) and Compressed Air Energy Storage (CAES). The Underground Energy Storage Program objectives, approach, structure, and milestones are described, and technical activities and progress in the STES and CAES areas are summarized. STES activities include aquifer thermal energy storage technology studies and STES technology assessment and development. CAES activities include reservoir stability studies and second-generation concepts studies. (LEW)

  5. On Locality in Distributed Storage Systems

    CERN Document Server

    Rawat, Ankit Singh

    2012-01-01

    This paper studies the design of codes for distributed storage systems (DSS) that enable local repair in the event of node failure. This paper presents locally repairable codes based on low degree multivariate polynomials. Its code construction mechanism extends work on Noisy Interpolating Set by Dvir et al. \\cite{dvir2011}. The paper presents two classes of codes that allow node repair to be performed by contacting 2 and 3 surviving nodes respectively. It further shows that both classes are good in terms of their rate and minimum distance, and allow their rate to be bartered for greater flexibility in the repair process.

  6. Rapid charging of thermal energy storage materials through plasmonic heating.

    Science.gov (United States)

    Wang, Zhongyong; Tao, Peng; Liu, Yang; Xu, Hao; Ye, Qinxian; Hu, Hang; Song, Chengyi; Chen, Zhaoping; Shang, Wen; Deng, Tao

    2014-01-01

    Direct collection, conversion and storage of solar radiation as thermal energy are crucial to the efficient utilization of renewable solar energy and the reduction of global carbon footprint. This work reports a facile approach for rapid and efficient charging of thermal energy storage materials by the instant and intense photothermal effect of uniformly distributed plasmonic nanoparticles. Upon illumination with both green laser light and sunlight, the prepared plasmonic nanocomposites with volumetric ppm level of filler concentration demonstrated a faster heating rate, a higher heating temperature and a larger heating area than the conventional thermal diffusion based approach. With controlled dispersion, we further demonstrated that the light-to-heat conversion and thermal storage properties of the plasmonic nanocomposites can be fine-tuned by engineering the composition of the nanocomposites.

  7. Statement of Work Electrical Energy Storage System Installation at Sandia National Laboratories.

    Energy Technology Data Exchange (ETDEWEB)

    Schenkman, Benjamin L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-03-01

    Sandia is seeking to procure a 1 MWh energy storage system. It will be installed at the existing Energy Storage Test Pad, which is located at Sandia National Laboratories in Albuquerque, New Mexico. This energy storage system will be a daily operational system, but will also be used as a tool in our Research and development work. The system will be part of a showcase of Sandia distributed energy technologies viewed by many distinguished delegates.

  8. Electric Vehicles Mileage Extender Kinetic Energy Storage

    Science.gov (United States)

    Jivkov, Venelin; Draganov, Vutko; Stoyanova, Yana

    2015-03-01

    The proposed paper considers small urban vehicles with electric hybrid propulsion systems. Energy demands are examined on the basis of European drive cycle (NEUDC) and on an energy recuperation coefficient and are formulated for description of cycle energy transfers. Numerical simulation results show real possibilities for increasing in achievable vehicle mileage at the same energy levels of a main energy source - the electric battery. Kinetic energy storage (KES), as proposed to be used as an energy buffer and different structural schemes of the hybrid propulsion system are commented. Minimum energy levels for primary (the electric battery) and secondary (KES) sources are evaluated. A strategy for reduced power flows control is examined, and its impact on achievable vehicle mileage is investigated. Results show an additional increase in simulated mileage at the same initial energy levels.

  9. Energy storage deployment and innovation for the clean energy transition

    Science.gov (United States)

    Kittner, Noah; Lill, Felix; Kammen, Daniel M.

    2017-09-01

    The clean energy transition requires a co-evolution of innovation, investment, and deployment strategies for emerging energy storage technologies. A deeply decarbonized energy system research platform needs materials science advances in battery technology to overcome the intermittency challenges of wind and solar electricity. Simultaneously, policies designed to build market growth and innovation in battery storage may complement cost reductions across a suite of clean energy technologies. Further integration of R&D and deployment of new storage technologies paves a clear route toward cost-effective low-carbon electricity. Here we analyse deployment and innovation using a two-factor model that integrates the value of investment in materials innovation and technology deployment over time from an empirical dataset covering battery storage technology. Complementary advances in battery storage are of utmost importance to decarbonization alongside improvements in renewable electricity sources. We find and chart a viable path to dispatchable US$1 W‑1 solar with US$100 kWh‑1 battery storage that enables combinations of solar, wind, and storage to compete directly with fossil-based electricity options.

  10. Lessons Learned from the Puerto Rico Battery Energy Storage System

    Energy Technology Data Exchange (ETDEWEB)

    BOYES, JOHN D.; DE ANA, MINDI FARBER; TORRES, WENCESLANO

    1999-09-01

    The Puerto Rico Electric Power Authority (PREPA) installed a distributed battery energy storage system in 1994 at a substation near San Juan, Puerto Rico. It was patterned after two other large energy storage systems operated by electric utilities in California and Germany. The U.S. Department of Energy (DOE) Energy Storage Systems Program at Sandia National Laboratories has followed the progress of all stages of the project since its inception. It directly supported the critical battery room cooling system design by conducting laboratory thermal testing of a scale model of the battery under simulated operating conditions. The Puerto Rico facility is at present the largest operating battery storage system in the world and is successfully providing frequency control, voltage regulation, and spinning reserve to the Caribbean island. The system further proved its usefulness to the PREPA network in the fall of 1998 in the aftermath of Hurricane Georges. The owner-operator, PREPA, and the architect/engineer, vendors, and contractors learned many valuable lessons during all phases of project development and operation. In documenting these lessons, this report will help PREPA and other utilities in planning to build large energy storage systems.

  11. Energy Proportionality for Disk Storage Using Replication

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jinoh; Rotem, Doron

    2010-09-09

    Energy saving has become a crucial concern in datacenters as several reports predict that the anticipated energy costs over a three year period will exceed hardware acquisition. In particular, saving energy for storage is of major importance as storage devices (and cooling them off) may contribute over 25 percent of the total energy consumed in a datacenter. Recent work introduced the concept of energy proportionality and argued that it is a more relevant metric than just energy saving as it takes into account the tradeoff between energy consumption and performance. In this paper, we present a novel approach, called FREP (Fractional Replication for Energy Proportionality), for energy management in large datacenters. FREP includes areplication strategy and basic functions to enable flexible energy management. Specifically, our method provides performance guarantees by adaptively controlling the power states of a group of disks based on observed and predicted workloads. Our experiments, using a set of real and synthetic traces, show that FREP dramatically reduces energy requirements with a minimal response time penalty.

  12. Flywheel energy storage. II - Magnetically suspended superflywheel

    Science.gov (United States)

    Kirk, J. A.; Studer, P. A.

    1977-01-01

    This article, the second of a two part paper, describes the general design requirements for a flywheel energy storage system. A new superflywheel energy storage system, using a spokeless, magnetically suspended, composite material pierced disk rotor is proposed. The new system is configured around a permanent magnet ('flux biased') magnetic suspension system with active control in the radial direction and passive control in the axial direction. The storage ring is used as a moving rotor and electronic commutation of stationary armature coils is proposed. There is no mechanical contact with the rotating ring and long life and low run down losses are projected. A discussion of major components for a 10 kwh system is presented.

  13. 配电网络公共储能位置与容量的优化方法%Optimal Method for Placement and Capacity of Energy Storage in Distribution System

    Institute of Scientific and Technical Information of China (English)

    肖峻; 张泽群; 梁海深

    2015-01-01

    在含有分布式电源的配电网中为储能选取合适的位置和容量,可以有效地减少储能投资,优化整个电网的经济效益。为此,提出了一种储能容量和位置优化方法,在现有文献方法的基础上增加了容量修正环节,能够在达到相同目标的前提下降低总成本,迭代收敛更快。首先,建立了储能位置与容量的优化模型:以整个电网总成本最小为目标,以储能充放电功率、容量及所在位置节点为优化变量,约束条件考虑了荷电状态(SOC)限制及充放电功率、电压上下限;然后,给出了采用遗传算法求解模型的步骤;最后,对 IEEE 33节点配电网的算例验证结果表明,与传统方法相比,在优化后得到同样的储能位置时,所提方法得到的储能容量更小,且电网总成本更低。%The optimization of placement and capacity of energy storage in a distribution system is capable of reducing the investment in energy storage as well as optimizing the economic benefit of the whole grid.In order to achieve this goal,an optimal method for the placement and capacity of energy storage in the distribution system is proposed,which adds the energy storage capacity correction step to the traditional method,thus effectively achieving lower investment and faster speed at the same target.First,the optimal model for placement and capacity of energy storage is established,which takes the minimum value of the total cost of the whole power grid as the objective while the energy storage capacity,location,charging and discharging power as optimization variables and the limitation on energy charged state,the charging/discharging efficiency and the upper and lower bounds for voltage as constraint conditions.Then,the method solving the model is given.In the end,an IEEE 33-node distribution grid is taken as an example to verify the better performance of the proposed method for its smaller energy storage capacity

  14. An interdisciplinary review of energy storage for communities

    DEFF Research Database (Denmark)

    Parra, David; Swierczynski, Maciej Jozef; Stroe, Daniel-Ioan

    2017-01-01

    Given the increasing penetration of renewable energy technologies as distributed generation embedded in the consumption centres, there is growing interest in energy storage systems located very close to consumers. These systems allow to increase the amount of renewable energy generation consumed...... locally, they provide opportunities for demand-side management and help to decarbonise the electricity, heating and transport sectors. In this paper, the authors present an interdisciplinary review of community energy storage (CES) with a focus on its potential role and challenges as a key element within...... the wider energy system. The discussion includes: the whole spectrum of applications and technologies with a strong emphasis on end user applications; techno-economic, environmental and social assessments of CES; and an outlook on CES from the customer, utility company and policy-maker perspectives...

  15. Energy production, conversion, storage, conservation, and coupling

    CERN Document Server

    Demirel, Yaşar

    2012-01-01

    Understanding the sustainable use of energy in various processes is an integral part of engineering and scientific studies, which rely on a sound knowledge of energy systems. Whilst many institutions now offer degrees in energy-related programs, a comprehensive textbook, which introduces and explains sustainable energy systems and can be used across engineering and scientific fields, has been lacking. Energy: Production, Conversion, Storage, Conservation, and Coupling provides the reader with a practical understanding of these five main topic areas of energy including 130 examples and over 600 practice problems. Each chapter contains a range of supporting figures, tables, thermodynamic diagrams and charts, while the Appendix supplies the reader with all the necessary data including the steam tables. This new textbook presents a clear introduction of basic vocabulary, properties, forms, sources, and balances of energy before advancing to the main topic areas of: • Energy production and conversion in importa...

  16. Hydrochemistry and energy storage in aquifers

    NARCIS (Netherlands)

    Andersson, O.; Appelo, C.A.J.; Brons, H.J.; Dufour, F.C.; Griffioen, J.; Jenne, E.A.; Lyklema, J.W.; Mourik, G.J. van; Snijders, A.L.; Willemsen, A.; Zehnder, A.J.B.

    1990-01-01

    This volume of the series Proceedings and Information of the TNO Committee on Hydrological Research (CHO-TNO) contains the contributions as presented on the 48th technical meeting of the CHO-TNO, "Hydrochemistry and energy storage in aquifers". During this symposium recent results have been presente

  17. Fuel Cells and Electrochemical Energy Storage.

    Science.gov (United States)

    Sammells, Anthony F.

    1983-01-01

    Discusses the nature of phosphoric acid, molten carbonate, and solid oxide fuel cells and major features and types of batteries used for electrical energy storage. Includes two tables presenting comparison of major battery features and summary of major material problems in the sodium-sulfur and lithium-alloy metal sulfide batteries. (JN)

  18. Biogeochemical aspects of aquifer thermal energy storage.

    NARCIS (Netherlands)

    Brons, H.J.

    1992-01-01

    During the process of aquifer thermal energy storage the in situ temperature of the groundwater- sediment system may fluctuate significantly. As a result the groundwater characteristics can be considerably affected by a variety of chemical, biogeochemical and microbiological reactions. The inter

  19. Start It up: Flywheel Energy Storage Efficiency

    Science.gov (United States)

    Dunn, Michelle

    2011-01-01

    The purpose of this project was to construct and test an off-grid photovoltaic (PV) system in which the power from a solar array could be stored in a rechargeable battery and a flywheel motor generator assembly. The mechanical flywheel energy storage system would in turn effectively power a 12-volt DC appliance. The voltage and current of…

  20. Hydrochemistry and energy storage in aquifers

    NARCIS (Netherlands)

    Andersson, O.; Appelo, C.A.J.; Brons, H.J.; Dufour, F.C.; Griffioen, J.; Jenne, E.A.; Lyklema, J.W.; Mourik, G.J. van; Snijders, A.L.; Willemsen, A.; Zehnder, A.J.B.

    1990-01-01

    This volume of the series Proceedings and Information of the TNO Committee on Hydrological Research (CHO-TNO) contains the contributions as presented on the 48th technical meeting of the CHO-TNO, "Hydrochemistry and energy storage in aquifers". During this symposium recent results have been

  1. Energy Efficient Storage and Transfer of Cryogens

    Science.gov (United States)

    Fesmire, James E.

    2013-01-01

    Cryogenics is globally linked to energy generation, storage, and usage. Thermal insulation systems research and development is an enabling part of NASA's technology goals for Space Launch and Exploration. New thermal testing methodologies and materials are being transferred to industry for a wide range of commercial applications.

  2. Review: electrolytes for electrochemical energy storage

    OpenAIRE

    Xia, Lin; Yu, Linpo; Hu, Di; Chen, George Z.

    2017-01-01

    An electrolyte is a key component of electrochemical energy storage (EES) devices and its properties greatly affect the energy capacity, rate performance, cyclability and safety of all EES devices. This article offers a critical review of the recent progress and challenges in electrolyte research and development, particularly for supercapacitors and supercapatteries, rechargeable batteries (such as lithium-ion and sodium-ion batteries), and redox flow batteries (including fuel cells in a broa...

  3. Analysis Insights: Energy Storage - Possibilities for Expanding Electric Grid Flexibility

    Energy Technology Data Exchange (ETDEWEB)

    2016-02-01

    NREL Analysis Insights mines our body of analysis work to synthesize topical insights and key findings. In this issue, we explore energy storage and the role it is playing and could potentially play in increasing grid flexibility and renewable energy integration. We explore energy storage as one building block for a more flexible power system, policy and R and D as drivers of energy storage deployment, methods for valuing energy storage in grid applications, ways that energy storage supports renewable integration, and emerging opportunities for energy storage in the electric grid.

  4. Integrated Building Energy Systems Design Considering Storage Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Stadler, Michael; Marnay, Chris; Siddiqui, Afzal; Lai, Judy; Aki, Hirohisa

    2009-04-07

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

  5. Electrical Energy Storage for Renewable Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Helms, C. R. [Univ. of Texas, Dallas, TX (United States); Cho, K. J. [Univ. of Texas, Dallas, TX (United States); Ferraris, John [Univ. of Texas, Dallas, TX (United States); Balkus, Ken [Univ. of Texas, Dallas, TX (United States); Chabal, Yves [Univ. of Texas, Dallas, TX (United States); Gnade, Bruce [Univ. of Texas, Dallas, TX (United States); Rotea, Mario [Univ. of Texas, Dallas, TX (United States); Vasselli, John [Univ. of Texas, Dallas, TX (United States)

    2012-08-31

    This program focused on development of the fundamental understanding necessary to significantly improve advanced battery and ultra-capacitor materials and systems to achieve significantly higher power and energy density on the one hand, and significantly lower cost on the other. This program spanned all the way from atomic-level theory, to new nanomaterials syntheses and characterization, to system modeling and bench-scale technology demonstration. This program not only delivered significant advancements in fundamental understanding and new materials and technology, it also showcased the power of the cross-functional, multi-disciplinary teams at UT Dallas and UT Tyler for such work. These teams are continuing this work with other sources of funding from both industry and government.

  6. Hydrogen based energy storage for energy harvesting systems

    Energy Technology Data Exchange (ETDEWEB)

    Bretthauer, Christian

    2011-07-01

    This thesis presents the development of a novel type of silicon integrated alkaline fuel cell - electrolyser device as on-chip energy storage. The alkaline environment allows not only a facilitated water management compared to state-of-the-art acidic integrated fuel cell systems, it further allows the usage of non-precious metal catalysts and hydrogen storage materials, for the first time. Additionally, a button cell shaped version of the accumulator is presented that incorporates a photoactive SrTiO{sub 3} ceramic for solar recharge. The solar charging mechanism is shown to be inherently self-regulating such that the cell depicts essentially a Micro Hydrogen Economy including energy conversion, energy management and energy storage in a single device. (orig.)

  7. Energy Storage. Teachers Guide. Science Activities in Energy.

    Science.gov (United States)

    Jacobs, Mary Lynn, Ed.

    Included in this science activities energy package for students in grades 4-10 are 12 activities related to energy storage. Each activity is outlined on the front and back of a single sheet and is introduced by a key question. Most of the activities can be completed in the classroom with materials readily available in any community. Among the…

  8. Methods for Distributed Optimal Energy Management

    DEFF Research Database (Denmark)

    Brehm, Robert

    The presented research deals with the fundamental underlying methods and concepts of how the growing number of distributed generation units based on renewable energy resources and distributed storage devices can be most efficiently integrated into the existing utility grid. In contrast to convent......The presented research deals with the fundamental underlying methods and concepts of how the growing number of distributed generation units based on renewable energy resources and distributed storage devices can be most efficiently integrated into the existing utility grid. In contrast...... to conventional centralised optimal energy flow management systems, here-in, focus is set on how optimal energy management can be achieved in a decentralised distributed architecture such as a multi-agent system. Distributed optimisation methods are introduced, targeting optimisation of energy flow in virtual...... micro-grids by prevention of meteorologic power flows into high voltage grids. A method, based on mathematical optimisation and a consensus algorithm is introduced and evaluated to coordinate charge/discharge scheduling for batteries between a number of buildings in order to improve self...

  9. Flywheel Energy Storage Technology Being Developed

    Science.gov (United States)

    Wolff, Frederick J.

    2001-01-01

    A flywheel energy storage system was spun to 60,000 rpm while levitated on magnetic bearings. This system is being developed as an energy-efficient replacement for chemical battery systems. Used in groups, the flywheels can have two functions providing attitude control for a spacecraft in orbit as well as providing energy storage. The first application for which the NASA Glenn Research Center is developing the flywheel is the International Space Station, where a two-flywheel system will replace one of the nickel-hydrogen battery strings in the space station's power system. The 60,000-rpm development rotor is about one-eighth the size that will be needed for the space station (0.395 versus 3.07 kWhr).

  10. Compressed Air Energy Storage in Denmark

    DEFF Research Database (Denmark)

    Salgi, Georges Garabeth; Lund, Henrik

    2006-01-01

    the prices from fluctuating to the extent that CAES investments have not been considered feasible. This report studies the effect of technological development and possible future price development of investments in CAES plants of various capacities. It is found that advanced high-efficiency CAES plants......Compressed air energy storage system (CAES) is a technology which can be used for integrating more fluctuating renewable energy sources into the electricity supply system. On a utility scale, CAES has a high feasibility potential compared to other storage technologies. Here, the technology...... is analysed with regard to the Danish energy system. In Denmark, wind power supplies 20% of the electricity demand and 50% is produced by combined heat and power (CHP). The operation of CAES requires high electricity price volatility. However, in the Nordic region, large hydro capacities have so far kept...

  11. Energy storage materials synthesized from ionic liquids.

    Science.gov (United States)

    Gebresilassie Eshetu, Gebrekidan; Armand, Michel; Scrosati, Bruno; Passerini, Stefano

    2014-12-01

    The advent of ionic liquids (ILs) as eco-friendly and promising reaction media has opened new frontiers in the field of electrochemical energy storage. Beyond their use as electrolyte components in batteries and supercapacitors, ILs have unique properties that make them suitable as functional advanced materials, media for materials production, and components for preparing highly engineered functional products. Aiming at offering an in-depth review on the newly emerging IL-based green synthesis processes of energy storage materials, this Review provides an overview of the role of ILs in the synthesis of materials for batteries, supercapacitors, and green electrode processing. It is expected that this Review will assess the status quo of the research field and thereby stimulate new thoughts and ideas on the emerging challenges and opportunities of IL-based syntheses of energy materials.

  12. Two-dimensional heterostructures for energy storage

    Science.gov (United States)

    Pomerantseva, Ekaterina; Gogotsi, Yury

    2017-07-01

    Two-dimensional (2D) materials provide slit-shaped ion diffusion channels that enable fast movement of lithium and other ions. However, electronic conductivity, the number of intercalation sites, and stability during extended cycling are also crucial for building high-performance energy storage devices. While individual 2D materials, such as graphene, show some of the required properties, none of them can offer all properties needed to maximize energy density, power density, and cycle life. Here we argue that stacking different 2D materials into heterostructured architectures opens an opportunity to construct electrodes that would combine the advantages of the individual building blocks while eliminating the associated shortcomings. We discuss characteristics of common 2D materials and provide examples of 2D heterostructured electrodes that showed new phenomena leading to superior electrochemical performance. We also consider electrode fabrication approaches and finally outline future steps to create 2D heterostructured electrodes that could greatly expand current energy storage technologies.

  13. Cost projections for Redox Energy storage systems

    Science.gov (United States)

    Michaels, K.; Hall, G.

    1980-01-01

    A preliminary design and system cost analysis was performed for the redox energy storage system. A conceptual design and cost estimate was prepared for each of two energy applications: (1) electric utility 100-MWh requirement (10-MW for ten hours) for energy storage for utility load leveling application, and (2) a 500-kWh requirement (10-kW for 50 hours) for use with a variety of residential or commercial applications, including stand alone solar photovoltaic systems. The conceptual designs were based on cell performance levels, system design parameters, and special material costs. These data were combined with estimated thermodynamic and hydraulic analysis to provide preliminary system designs. Results indicate that the redox cell stack to be amenable to mass production techniques with a relatively low material cost.

  14. Nanomaterials for renewable energy production and storage.

    Science.gov (United States)

    Chen, Xiaobo; Li, Can; Grätzel, Michaël; Kostecki, Robert; Mao, Samuel S

    2012-12-07

    Over the past decades, there have been many projections on the future depletion of the fossil fuel reserves on earth as well as the rapid increase in green-house gas emissions. There is clearly an urgent need for the development of renewable energy technologies. On a different frontier, growth and manipulation of materials on the nanometer scale have progressed at a fast pace. Selected recent and significant advances in the development of nanomaterials for renewable energy applications are reviewed here, and special emphases are given to the studies of solar-driven photocatalytic hydrogen production, electricity generation with dye-sensitized solar cells, solid-state hydrogen storage, and electric energy storage with lithium ion rechargeable batteries.

  15. Flywheel energy storage for electromechanical actuation systems

    Science.gov (United States)

    Hockney, Richard L.; Goldie, James H.; Kirtley, James L.

    1991-01-01

    The authors describe a flywheel energy storage system designed specifically to provide load-leveling for a thrust vector control (TVC) system using electromechanical actuators (EMAs). One of the major advantages of an EMA system over a hydraulic system is the significant reduction in total energy consumed during the launch profile. Realization of this energy reduction will, however, require localized energy storage capable of delivering the peak power required by the EMAs. A combined flywheel-motor/generator unit which interfaces directly to the 20-kHz power bus represents an ideal candidate for this load leveling. The overall objective is the definition of a flywheel energy storage system for this application. The authors discuss progress on four technical objectives: (1) definition of the specifications for the flywheel-motor/generator system, including system-level trade-off analysis; (2) design of the flywheel rotor; (3) design of the motor/generator; and (4) determination of the configuration for the power management system.

  16. Multiscale Simulations of Energy Storage in Polymers

    Science.gov (United States)

    Ranjan, V.; van Duin, A.; Buongiorno Nardelli, M.; Bernholc, J.

    2012-02-01

    Polypropelene is the most used capacitor dielectric for high energy density storage. However, exotic materials such as copolymerized PVDF and, more recently, polythiourea, could potentially lead to an order of magnitude increase in the stored energy density [1,2]. In our previous investigations we demonstrated that PVDF-CTFE possesses non-linear dielectric properties under applied electric field. These are characterized by transitions from non-polar to polar phases that lead enhanced energy density. Recent experiments [3] have also suggested that polythiourea may be another potential system with high energy-density storage and low loss. However, the characteristics of this emerging material are not yet understood and even its preferred crystalline phases are not known. We have developed a multiscale approach to predicting polymer self-organization using the REAX force field and molecular dynamics simulations. We find that polythiourea chains tend to coalesce in nanoribbon-type structures and prefer an anti-polar interchain ordering similar to PVDF. These results suggest a possible role of topological phase transitions in shaping energy storage in this system.[4pt] [1] B. Chu et al, Science 313, 334 (2006).[0pt] [2] V. Ranjan et al., PRL 99, 047801 (2007).[0pt] [3] Q. Zhang, private communication

  17. DTU international energy report 2013. Energy storage options for future sustainable energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Hvidtfeldt Larsen, H.; Soenderberg Petersen, L. (eds.)

    2013-11-01

    One of the great challenges in the transition to a non-fossil energy system with a high share of fluctuating renewable energy sources such as solar and wind is to align consumption and production in an economically satisfactory manner. Energy storage could provide the necessary balancing power to make this possible. This energy report addresses energy storage from a broad perspective: It analyses smaller stores that can be used locally in for example heat storage in the individual home or vehicle, such as electric cars or hydrogen cars. The report also addresses decentralized storage as flywheels and batteries linked to decentralized energy systems. In addition it addresses large central storages as pumped hydro storage and compressed air energy storage and analyse this in connection with international transmission and trading over long distances. The report addresses electrical storage, thermal storage and other forms of energy storage, for example conversion of biomass to liquid fuel and conversion of solar energy directly into hydrogen, as well as storage in transmission, grid storage etc. Finally, the report covers research, innovation and the future prospects and addresses the societal challenges and benefits of the use of energy storage. (Author)

  18. Hydrogen Energy Storage (HES) Activities at NREL; NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    Eichman, J.

    2015-04-21

    This presentation provides an overview of hydrogen and energy storage, including hydrogen storage pathways and international power-to-gas activities, and summarizes the National Renewable Energy Laboratory's hydrogen energy storage activities and results.

  19. Energy storage for improvement of wind power characteristics

    DEFF Research Database (Denmark)

    Rasmussen, Claus Nygaard

    2011-01-01

    Results from simulation of the influence of energy storage on the variability and availability of wind energy are presented here. Simulations have been done using a mathematical model of energy storage implemented in MATLAB. The obtained results show the quality improvement, of energy delivered...... by a combination of wind and energy storage, in relation to the size of the energy storage. The introduction of storage enables suppression of wind power fluctuations up to a timescale proportional to the storage energy capacity. Energy storage cannot provide availability of wind power at all times, but it can...... guarantee that a certain fraction of average wind power will be available within a given timeframe. The amount of storage energy capacity necessary for significant improvement of wind power availability, within a given period, is found to be approximately 20% of the energy produced in that period...

  20. Solar energy storage researchers information user study

    Energy Technology Data Exchange (ETDEWEB)

    Belew, W.W.; Wood, B.L.; Marle, T.L.; Reinhardt, C.L.

    1981-03-01

    The results of a series of telephone interviews with groups of users of information on solar energy storage are described. In the current study only high-priority groups were examined. Results from 2 groups of researchers are analyzed: DOE-Funded Researchers and Non-DOE-Funded Researchers. The data will be used as input to the determination of information products and services the Solar Energy Research Institute, the Solar Energy Information Data Bank Network, and the entire information outreach community should be preparing and disseminating.

  1. Energy conversion & storage program. 1994 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Cairns, E.J.

    1995-04-01

    The Energy Conversion and Storage Program investigates state-of-the-art electrochemistry, chemistry, and materials science technologies for: (1) development of high-performance rechargeable batteries and fuel cells; (2) development of high-efficiency thermochemical processes for energy conversion; (3) characterization of complex chemical processes and chemical species; (4) study and application of novel materials for energy conversion and transmission. Research projects focus on transport process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis.

  2. Energy Conversion & Storage Program, 1993 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Cairns, E.J.

    1994-06-01

    The Energy Conversion and Storage Program applies chemistry and materials science principles to solve problems in: production of new synthetic fuels; development of high-performance rechargeable batteries and fuel cells; development of high-efficiency thermochemical processes for energy conversion; characterization of complex chemical processes and chemical species; and the study and application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis.

  3. Electricity End Uses, Energy Efficiency, and Distributed Energy Resources Baseline

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, Lisa [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wei, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Morrow, William [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Deason, Jeff [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schiller, Steven R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Leventis, Greg [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Smith, Sarah [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Leow, Woei Ling [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Levin, Todd [Argonne National Lab. (ANL), Argonne, IL (United States); Plotkin, Steven [Argonne National Lab. (ANL), Argonne, IL (United States); Zhou, Yan [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States)

    2017-01-01

    This report was developed by a team of analysts at Lawrence Berkeley National Laboratory, with Argonne National Laboratory contributing the transportation section, and is a DOE EPSA product and part of a series of “baseline” reports intended to inform the second installment of the Quadrennial Energy Review (QER 1.2). QER 1.2 provides a comprehensive review of the nation’s electricity system and cover the current state and key trends related to the electricity system, including generation, transmission, distribution, grid operations and planning, and end use. The baseline reports provide an overview of elements of the electricity system. This report focuses on end uses, electricity consumption, electric energy efficiency, distributed energy resources (DERs) (such as demand response, distributed generation, and distributed storage), and evaluation, measurement, and verification (EM&V) methods for energy efficiency and DERs.

  4. The Energy Efficiency of Onboard Hydrogen Storage

    DEFF Research Database (Denmark)

    Jensen, Jens Oluf; Vestbø, Andreas Peter; Li, Qingfeng

    2007-01-01

    A number of the most common ways of storing hydrogen are reviewed in terms of energy efficiency. Distinction is made between energy losses during regeneration and during hydrogen liberation. In the latter case, the energy might have to be provided by part of the released hydrogen, and the true st...... storage density is then equivalently smaller. Systems covered include compressed and liquid hydrogen, reversible and irreversible metal hydrides, and methanol and ammonia.......A number of the most common ways of storing hydrogen are reviewed in terms of energy efficiency. Distinction is made between energy losses during regeneration and during hydrogen liberation. In the latter case, the energy might have to be provided by part of the released hydrogen, and the true...

  5. Fuel cell energy storage for Space Station enhancement

    Science.gov (United States)

    Stedman, J. K.

    1990-01-01

    Viewgraphs on fuel cell energy storage for space station enhancement are presented. Topics covered include: power profile; solar dynamic power system; photovoltaic battery; space station energy demands; orbiter fuel cell power plant; space station energy storage; fuel cell system modularity; energy storage system development; and survival power supply.

  6. Optimal Load Distribution of Microgrid With Energy Storage System Composed of Vanadium Redox Flow Battery%含钒电池储能的微电网负荷优化分配

    Institute of Scientific and Technical Information of China (English)

    陈光堂; 邱晓燕; 林伟

    2012-01-01

    储能系统是微电网的重要组成部分,其对微电网的稳定性、经济性与安全性有着非常重要的影响.以含钒液流储能电池(vanadium redox flow battery,VRB)系统的微电网为研究对象,建立了含钒电池储能微电网多目标负荷优化分配模型.以某微电网为例,分析讨论了钒电池对微电网带来的经济效益,同时研究了运行模式、控制策略和优化目标中权重等诸多因素对微电网负荷优化分配结果的影响,验证了所建立模型的有效性.%Energy storage system is an important component of microgrid and it greatly impacts the stability, security and economic operation of microgrid. Taking a microgrid containing energy storage system composed of vanadium redox flow battery (VRB) as research object, a multi-objective load distribution optimization model of microgrid with energy storage system composed of vanadium redox flow battery (VRB) is built. The economic benefit bought to microgrid by VRB is analyzed and researched, meanwhile the influences of the factors such as operating modes, control strategy and the weights of optimization objectives on load distribution optimization of microgrid are researched too, thus the effectiveness of the built model is verified.

  7. Coordinated Collaboration between Heterogeneous Distributed Energy Resources

    Directory of Open Access Journals (Sweden)

    Shahin Abdollahy

    2014-01-01

    Full Text Available A power distribution feeder, where a heterogeneous set of distributed energy resources is deployed, is examined by simulation. The energy resources include PV, battery storage, natural gas GenSet, fuel cells, and active thermal storage for commercial buildings. The resource scenario considered is one that may exist in a not too distant future. Two cases of interaction between different resources are examined. One interaction involves a GenSet used to partially offset the duty cycle of a smoothing battery connected to a large PV system. The other example involves the coordination of twenty thermal storage devices, each associated with a commercial building. Storage devices are intended to provide maximum benefit to the building, but it is shown that this can have a deleterious effect on the overall system, unless the action of the individual storage devices is coordinated. A network based approach is also introduced to calculate some type of effectiveness metric to all available resources which take part in coordinated operation. The main finding is that it is possible to achieve synergy between DERs on a system; however this required a unified strategy to coordinate the action of all devices in a decentralized way.

  8. Development of nanocomposites for energy storage devices

    Science.gov (United States)

    Khan, Md. Ashiqur Rahaman

    With the ever-increasing need in improving the performance and operation life of future mobile devices, developing higher power density energy storage devices has been receiving more attention. Lithium ion battery (LIB) and capacitor are two of the most widely used energy storage devices and have attracted increasing interest from both industrial and academic fields. Batteries have higher power density than capacitor but significantly longer charge/discharge rates. In order to further improve the performance of these energy storage devices, one of the approaches is to use high specific surface area nano-materials. Among all the nano-materials developed so far, one-dimensional nanowires are of special interests because of their high surface-to-volume ratio and aligned pathway for electron diffusion and conduction. Therefore, in this thesis work, zinc oxide nanowires are implemented as an anode along with carbon fiber/graphene to increase the performance of LIB while lead titanate nanowires are used to improve the energy density of capacitors. For batteries, zinc oxide nanowires are grown on carbon cloth by low temperature hydrothermal method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) are used to analyze morphology and crystal structures of samples. The performances of LIB using zinc oxide nanowire coated carbon cloth and bare carbon cloth are compared to show the improvement induced by zinc oxide nanowires. For capacitors, lead titanate (PTO) nanowires are used with Polyvinylidene fluoride (PVDF) to make nanocomposites of high dielectric constants. Lead titanate nanowires are synthesized by low temperature hydrothermal method. XRD and SEM are used to analyze as synthesized nanowires. Different volume fraction of PTO nanowires is used with PVDF to make dielectric for capacitor. Dielectric constant and breakdown voltage at variable frequency are determined to calculate energy density and specific energy density. The influence of temperature on

  9. A Numerical and Graphical Review of Energy Storage Technologies

    Directory of Open Access Journals (Sweden)

    Siraj Sabihuddin

    2014-12-01

    Full Text Available More effective energy production requires a greater penetration of storage technologies. This paper takes a looks at and compares the landscape of energy storage devices. Solutions across four categories of storage, namely: mechanical, chemical, electromagnetic and thermal storage are compared on the basis of energy/power density, specific energy/power, efficiency, lifespan, cycle life, self-discharge rates, capital energy/power costs, scale, application, technical maturity as well as environmental impact. It’s noted that virtually every storage technology is seeing improvements. This paper provides an overview of some of the problems with existing storage systems and identifies some key technologies that hold promise.

  10. Hydrogen based energy storage for solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Vanhanen, J.P.; Hagstroem, M.T.; Lund, P.H. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics; Leppaenen, J.R.; Nieminen, J.P. [Neste Oy (Finland)

    1998-12-31

    Hydrogen based energy storage options for solar energy systems was studied in order to improve their overall performance. A 1 kW photovoltaic hydrogen (PV-H2) pilot-plant and commercial prototype were constructed and a numerical simulation program H2PHOTO for system design and optimisation was developed. Furthermore, a comprehensive understanding of conversion (electrolysers and fuel cells) and storage (metal hydrides) technologies was acquired by the project partners. The PV-H{sub 2} power system provides a self-sufficient solution for applications in remote locations far from electric grids and maintenance services. (orig.)

  11. Multifunctional Energy Storage and Conversion Devices.

    Science.gov (United States)

    Huang, Yan; Zhu, Minshen; Huang, Yang; Pei, Zengxia; Li, Hongfei; Wang, Zifeng; Xue, Qi; Zhi, Chunyi

    2016-10-01

    Multifunctional energy storage and conversion devices that incorporate novel features and functions in intelligent and interactive modes, represent a radical advance in consumer products, such as wearable electronics, healthcare devices, artificial intelligence, electric vehicles, smart household, and space satellites, etc. Here, smart energy devices are defined to be energy devices that are responsive to changes in configurational integrity, voltage, mechanical deformation, light, and temperature, called self-healability, electrochromism, shape memory, photodetection, and thermal responsivity. Advisable materials, device designs, and performances are crucial for the development of energy electronics endowed with these smart functions. Integrating these smart functions in energy storage and conversion devices gives rise to great challenges from the viewpoint of both understanding the fundamental mechanisms and practical implementation. Current state-of-art examples of these smart multifunctional energy devices, pertinent to materials, fabrication strategies, and performances, are highlighted. In addition, current challenges and potential solutions from materials synthesis to device performances are discussed. Finally, some important directions in this fast developing field are considered to further expand their application.

  12. Reluctance apparatus for flywheel energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Hull, John R. (Downers Grove, IL)

    2000-01-01

    A motor generator for providing high efficiency, controlled voltage output or storage of energy in a flywheel system. A motor generator includes a stator of a soft ferromagnetic material, a motor coil and a generator coil, and a rotor has at least one embedded soft ferromagnetic piece. Control of voltage output is achieved by use of multiple stator pieces and multiple rotors with controllable gaps between the stator pieces and the soft ferromagnetic piece.

  13. On Design for Electrochemical Energy Storage Materials

    OpenAIRE

    Sakaushi, Ken

    2014-01-01

    In this dissertation, diverse strategic designs of energy storage materials were explored. The main aims were: affordability and high-performances. I) on eco-efficient synthesis of 1D intercalation compounds was described; a low-temperature aqueous solution synthesis of nanostructured 1D (molybdenum trioxide) MoO3 was developed. Subsequent self-assembly of the fibers to form large-scale freestanding films in paper-like structure was achieved without any assistance of organic compounds. I...

  14. DTU International Energy Report 2013:Energy storage options for future sustainable energy systems

    OpenAIRE

    2013-01-01

    One of the great challenges in the transition to a non-fossil energy system with a high share of fluctuating renewable energy sources such as solar and wind is to align consumption and production in an economically satisfactory manner. Energy storage could provide the necessary balancing power to make this possible. This energy report addresses energy storage from a broad perspective: It analyses smaller stores that can be used locally in for example heat storage in the individual home or veh...

  15. Evaluation of superconducting magnetic energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Little, A. D.

    1979-11-01

    Superconducting magnetic energy storage (SMES) systems differ from other storage systems presently in use, or considered for use, by the electric utility industry, principally because of the radically different technology involved. SMES also has certain unique advantages: it appears to be able to store and deliver energy at very high efficiency, and it can switch from the charge to discharge mode in a few tens of milliseconds. The combination of these two desirable characteristics distinguishes SMES from almost all other energy storage systems. This investigation was undertaken to discover if the nation and the electric utility industry might benefit sufficiently from the use of SMES systems to justify continued research and development support by DOE. At present, systems development is in a relatively early stage, and much component development for many of the major subsystems remains to be performed. It appears each SMES unit will be large and therefore expensive; also that the investment in research and development required to achieve final commercial success may be substantial.

  16. Smart Energy Storages for Integration of Renewables in 100% Independent Energy Systems

    DEFF Research Database (Denmark)

    Krajačić, Goran; Duić, Neven; Mathiesen, Brian Vad

    2010-01-01

    leads to decreased security of energy supply, due to current geopolitical situation in which main sources of fossil fuels are in unstable regions and in which the competition for those resources from developing countries is growing. EU energy strategy, and a compatible Croatian strategy, is focused...... for energy storage, in the primary or secondary form, in order to transfer energy surplus form period of excess to the period when there is a lack. The problem of storage systems is that they increase the cost of already expensive distributed and renewable energy sources, making them, in market circumstances...... with integration of the energy flows, the transformations and energy demand at the location of the energy end- use or close to it....

  17. Energy in buildings: Efficiency, renewables and storage

    Directory of Open Access Journals (Sweden)

    Koebel Matthias M.

    2017-01-01

    Full Text Available This lecture summary provides a short but comprehensive overview on the “energy and buildings” topic. Buildings account for roughly 40% of the global energy demands. Thus, an increased adoption of existing and upcoming materials and solutions for the building sector represents an enormous potential to reduce building related energy demands and greenhouse gas emissions. The central question is how the building envelope (insulation, fenestration, construction style, solar control affects building energy demands. Compared to conventional insulation materials, superinsulation materials such as vacuum insulation panels and silica aerogel achieve the same thermal performance with significantly thinner insulation layers. With low-emissivity coatings and appropriate filler gasses, double and triple glazing reduce thermal losses by up to an order of magnitude compared to old single pane windows, while vacuum insulation and aerogel filled glazing could reduce these even further. Electrochromic and other switchable glazing solutions maximize solar gains during wintertime and minimize illumination demands whilst avoiding overheating in summer. Upon integration of renewable energy systems into the building energy supply, buildings can become both producers and consumers of energy. Combined with dynamic user behavior, temporal variations in the production of renewable energy require appropriate storage solutions, both thermal and electrical, and the integration of buildings into smart grids and energy district networks. The combination of these measures allows a reduction of the existing building stock by roughly a factor of three —a promising, but cost intensive way, to prepare our buildings for the energy turnaround.

  18. Energy in buildings: Efficiency, renewables and storage

    Science.gov (United States)

    Koebel, Matthias M.

    2017-07-01

    This lecture summary provides a short but comprehensive overview on the "energy and buildings" topic. Buildings account for roughly 40% of the global energy demands. Thus, an increased adoption of existing and upcoming materials and solutions for the building sector represents an enormous potential to reduce building related energy demands and greenhouse gas emissions. The central question is how the building envelope (insulation, fenestration, construction style, solar control) affects building energy demands. Compared to conventional insulation materials, superinsulation materials such as vacuum insulation panels and silica aerogel achieve the same thermal performance with significantly thinner insulation layers. With low-emissivity coatings and appropriate filler gasses, double and triple glazing reduce thermal losses by up to an order of magnitude compared to old single pane windows, while vacuum insulation and aerogel filled glazing could reduce these even further. Electrochromic and other switchable glazing solutions maximize solar gains during wintertime and minimize illumination demands whilst avoiding overheating in summer. Upon integration of renewable energy systems into the building energy supply, buildings can become both producers and consumers of energy. Combined with dynamic user behavior, temporal variations in the production of renewable energy require appropriate storage solutions, both thermal and electrical, and the integration of buildings into smart grids and energy district networks. The combination of these measures allows a reduction of the existing building stock by roughly a factor of three —a promising, but cost intensive way, to prepare our buildings for the energy turnaround.

  19. 基于分布式发电的多类型储能系统的设计与应用%Hybrid Energy Storage System Based on Distributed Generation

    Institute of Scientific and Technical Information of China (English)

    孙博; 魏海坤

    2016-01-01

    In view of the hybrid energy storage system based on the distributed generation,this paper designs appIica-tion system for hybrid energy storage system,incIuding remote monitoring,energy management and coordination controI.The system wiI meet the needs of safe,reIiabIe,high efficiency and economic operation through the design of system topoIogy, software and hardware,and optimizes the operation and appIication of various equipments in the system.%针对基于分布式发电的多类型储能系统,构建一套涵盖远程监控、能量管理及协调控制功能的多类型储能应用系统,通过系统拓扑设计及软硬件方案设计,满足多类型储能系统在分布式发电应用中安全、可靠、高效、经济运行的需要,优化系统内各种设备的运行与应用。

  20. FLSR - The Frankfurt low energy storage ring

    Science.gov (United States)

    Stiebing, K. E.; Alexandrov, V.; Dörner, R.; Enz, S.; Kazarinov, N. Yu.; Kruppi, T.; Schempp, A.; Schmidt Böcking, H.; Völp, M.; Ziel, P.; Dworak, M.; Dilfer, W.

    2010-02-01

    An electrostatic storage ring for low-energy ions with a design energy of 50 keV is presently being set up at the Institut für Kernphysik der Johann Wolfgang Goethe-Universität Frankfurt am Main, Germany (IKF). This new device will provide a basis for new experiments on the dynamics of ionic and molecular collisions, as well as for high precision and time resolved laser spectroscopy. In this article, the design parameters of this instrument are reported.

  1. Simulation of Flywheel Energy Storage System Controls

    Science.gov (United States)

    Truong, Long V.; Wolff, Frederick J.; Dravid, Narayan

    2001-01-01

    This paper presents the progress made in the controller design and operation of a flywheel energy storage system. The switching logic for the converter bridge circuit has been redefined to reduce line current harmonics, even at the highest operating speed of the permanent magnet motor-generator. An electromechanical machine model is utilized to simulate charge and discharge operation of the inertial energy in the flywheel. Controlling the magnitude of phase currents regulates the rate of charge and discharge. The resulting improvements are demonstrated by simulation.

  2. Economic Modeling of Compressed Air Energy Storage

    Directory of Open Access Journals (Sweden)

    Rui Bo

    2013-04-01

    Full Text Available Due to the variable nature of wind resources, the increasing penetration level of wind power will have a significant impact on the operation and planning of the electric power system. Energy storage systems are considered an effective way to compensate for the variability of wind generation. This paper presents a detailed production cost simulation model to evaluate the economic value of compressed air energy storage (CAES in systems with large-scale wind power generation. The co-optimization of energy and ancillary services markets is implemented in order to analyze the impacts of CAES, not only on energy supply, but also on system operating reserves. Both hourly and 5-minute simulations are considered to capture the economic performance of CAES in the day-ahead (DA and real-time (RT markets. The generalized network flow formulation is used to model the characteristics of CAES in detail. The proposed model is applied on a modified IEEE 24-bus reliability test system. The numerical example shows that besides the economic benefits gained through energy arbitrage in the DA market, CAES can also generate significant profits by providing reserves, compensating for wind forecast errors and intra-hour fluctuation, and participating in the RT market.

  3. Thermal Energy Storage with Phase Change Material

    Directory of Open Access Journals (Sweden)

    Lavinia Gabriela SOCACIU

    2012-08-01

    Full Text Available Thermal energy storage (TES systems provide several alternatives for efficient energy use and conservation. Phase change materials (PCMs for TES are materials supplying thermal regulation at particular phase change temperatures by absorbing and emitting the heat of the medium. TES in general and PCMs in particular, have been a main topic in research for the last 30 years, but although the information is quantitatively enormous, it is also spread widely in the literature, and difficult to find. PCMs absorb energy during the heating process as phase change takes place and release energy to the environment in the phase change range during a reverse cooling process. PCMs possesses the ability of latent thermal energy change their state with a certain temperature. PCMs for TES are generally solid-liquid phase change materials and therefore they need encapsulation. TES systems using PCMs as a storage medium offers advantages such as high TES capacity, small unit size and isothermal behaviour during charging and discharging when compared to the sensible TES.

  4. Assessment of flywheel energy storage for spacecraft power systems

    Science.gov (United States)

    Rodriguez, G. E.; Studer, P. A.; Baer, D. A.

    1983-01-01

    The feasibility of inertial energy storage in a spacecraft power system is evaluated on the basis of a conceptual integrated design that encompasses a composite rotor, magnetic suspension, and a permanent magnet (PM) motor/generator for a 3-kW orbital average payload at a bus distribution voltage of 250 volts dc. The conceptual design, which evolved at the Goddard Space Flight Center (GSFC), is referred to as a Mechanical Capacitor. The baseline power system configuration selected is a series system employing peak-power-tracking for a Low Earth-Orbiting application. Power processing, required in the motor/generator, provides a potential alternative configurations that can only be achieved in systems with electrochemical energy storage by the addition of power processing components. One such alternative configuration provides for peak-power-tracking of the solar array and still maintains a regulated bus, without the expense of additional power processing components. Precise speed control of the two counterrotating wheels is required to reduce interaction with the attitude control system (ACS) or alternatively, used to perform attitude control functions. Critical technologies identified are those pertaining to the energy storage element and are prioritized as composite wheel development, magnetic suspension, motor/generator, containment, and momentum control. Comparison with a 3-kW, 250-Vdc power system using either NiCd or NiH2 for energy storage results in a system in which inertial energy storage offers potential advantages in lifetime, operating temperature, voltage regulation, energy density, charge control, and overall system weight reduction.

  5. Improvements in magnetic bearing performance for flywheel energy storage

    Science.gov (United States)

    Plant, David P.; Anand, Davinder K.; Kirk, James A.; Calomeris, Anthony J.; Romero, Robert L.

    1988-01-01

    The paper considers the development of a 500-Watt-hour magnetically suspended flywheel stack energy storage system. The work includes hardware testing results from a stack flywheel energy storage system, improvements in the area of noncontacting displacement transducers, and performance enhancements of magnetic bearings. Experimental results show that a stack flywheel energy storage system is feasible technology.

  6. Research for superconducting energy storage patterns and its practical countermeasures

    Science.gov (United States)

    Lin, D. H.; Cui, D. J.; Li, B.; Teng, Y.; Zheng, G. L.; Wang, X. Q.

    2013-10-01

    In this paper, we attempt to introduce briefly the significance, the present status, as well as the working principle of the primary patterns of the superconducting energy storage system, first of all. According to the defect on the lower energy storage density of existed superconducting energy storage device, we proposed some new ideas and strategies about how to improve the energy storage density, in which, a brand-new but a tentative proposal regarding the concept of energy compression was emphasized. This investigation has a certain reference value towards the practical application of the superconducting energy storage.

  7. Thermal energy storage for sustainable energy consumption : fundamentals, case studies and design

    CERN Document Server

    Paksoy, Halime

    2007-01-01

    We all share a small planet. Our growing thirst for energy already threatens the future of our earth. Fossil fuels - energy resources of today - are not evenly distributed on the earth. 10 per cent of the world's population exploits 90 per cent of its resources. Today's energy systems rely heavily on fossil fuel resources which are diminishing ever faster. The world must prepare for a future without fossil fuels. Thermal energy storage provides us with a flexible heating and/or cooling tool to combat climate change through conserving energy and increasing energy while utilizing natural renewab

  8. Distributed Wind Energy in Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, John [Boise State Univ., ID (United States); Johnson, Kathryn [Colorado School of Mines, Golden, CO (United States); Haynes, Todd [Boise State Univ., ID (United States); Seifert, Gary [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2009-01-31

    This project is a research and development program aimed at furthering distributed wind technology. In particular, this project addresses some of the barriers to distributed wind energy utilization in Idaho.

  9. Operation of NRL Homopolar Generator into Parallel Energy Storage Inductor

    Science.gov (United States)

    2013-06-01

    energy storage . In this system a self-excited homopolar generator (HPG) serves to transfer rotational energy from flywheels to...magnetic energy in the storage inductor. A single 1.4-rnH solenoid inductor enclosing the flywheels can be energized to 60 kA and serves both as energy ...the energy storage circuit time constant were 1 s, an energy of 2 MJ could be obtained with an initial flywheel speed of 260 rps. As a

  10. Distributed Energy Resources Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — NREL's Distributed Energy Resources Test Facility (DERTF) is a working laboratory for interconnection and systems integration testing. This state-of-the-art facility...

  11. Distributed Energy Resources Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — NREL's Distributed Energy Resources Test Facility (DERTF) is a working laboratory for interconnection and systems integration testing. This state-of-the-art facility...

  12. Centrifugal Spinning and Its Energy Storage Applications

    Science.gov (United States)

    Yao, Lu

    Lithium-ion batteries (LIBs) and supercapacitors are important electrochemical energy storage systems. LIBs have high specific energy density, long cycle life, good thermal stability, low self-discharge, and no memory effect. However, the low abundance of Li in the Earth's crust and the rising cost of LIBs urge the attempts to develop alternative energy storage systems. Recently, sodium-ion batteries (SIBs) have become an attractive alternative to LIBs due to the high abundance and low cost of Na. Although the specific capacity and energy density of SIBs are not as high as LIBs, SIBs can still be promising power sources for certain applications such as large-scale, stationary grids. Supercapacitors are another important class of energy storage devices. Electric double-layer capacitors (EDLCs) are one important type of supercapacitors and they exhibit high power density, long cycle life, excellent rate capability and environmental friendliness. The potential applications of supercapacitors include memory protection in electronic circuitry, consumer portable electronic devices, and electrical hybrid vehicles. The electrochemical performance of SIBs and EDLCs is largely dependent on the electrode materials. Therefore, development of superior electrodes is the key to achieve highperformance alternative energy storage systems. Recently, one-dimensional nano-/micro-fiber based electrodes have become promising candidates in energy storage because they possess a variety of desirable properties including large specific surface area, well-guided ionic/electronic transport, and good electrode-electrolyte contact, which contribute to enhanced electrochemical performance. Currently, most nano-/micro-fiber based electrodes are prepared via electrospinning method. However, the low production rate of this approach hinders its practical application in the production of fibrous electrodes. Thus, it is significantly important to employ a rapid, low-cost and scalable nano

  13. Distributed Storage Inverter and Legacy Generator Integration Plus Renewables Solution for Microgrids

    Science.gov (United States)

    2015-07-01

    with small-scale power storage can maintain power quality in islanded mode with minimal use of the generators during non-optimal (e.g. cloud covered...inverter ( advantage of short term storage ) and enables microgrid upgrade of legacy generator assets (integration of inverter and generator controllers...microgrid stability, and can further be integrated with the distributed power storage to address intermittent loss of PV energy as when a cloud passes

  14. Federating Distributed Storage For Clouds In ATLAS

    CERN Document Server

    Berghaus, Frank; The ATLAS collaboration

    2017-01-01

    Input data for applications that run in cloud computing centres can be stored at distant repositories, often with multiple copies of the popular data stored at many sites. Locating and retrieving the remote data can be challenging, and we believe that federating the storage can address this problem. A federation would locate the closest copy of the data currently on the basis of GeoIP information. Currently we are using the DynaFed data federation software solution developed by CERN IT. DynaFed supports several industry standards for connection protocols like Amazon's S3, Microsofts Azure, as well as WebDav and HTTP. Protocol dependent authentication is hidden from the user by using their X509 certificate. We have setup an instance of DynaFed and integrated it into the ATLAS Data Distribution Management system. We report on the challenges faced during the installation and integration. We have tested ATLAS analysis jobs submitted by the PanDA production system and we report on our first experiences with its op...

  15. Design of a high temperature subsurface thermal energy storage system

    Science.gov (United States)

    Zheng, Qi

    horizontal-to-vertical permeability ratio is favored by the storage system. A basin-shape reservoir is more favored than a flat reservoir, while a flat reservoir is better than a dome-shape reservoir. The effect of aquifer stratification is variable: it depends on the relative position of the well screen and the impermeable lenses within the reservoir. From the operational aspect, the well screen position is crucial and properly shortening the screen length can help heat recovery. The proportion of the injection/storage/recovery processes within a cycle, rather than their exact lengths, affects the storage efficiency. Reservoir preheating helps improve the energy storage efficiency for the first several cycles. However, it does not contribute much to the system performance in the long run. Simulations also indicate that buoyancy effect is of significant importance in heat distribution and the plume migration. Reducing the gravity override effect of the heat plume could be an important consideration in efficiency optimization.

  16. Energy Storage Systems as a Compliment to Wind Power

    Science.gov (United States)

    Sieling, Jared D.; Niederriter, C. F.; Berg, D. A.

    2006-12-01

    As Gustavus Adolphus College prepares to install two wind turbines on campus, we are faced with the question of what to do with the excess electricity that is generated. Since the College pays a substantial demand charge, it would seem fiscally responsible to store the energy and use it for peak shaving, instead of selling it to the power company at their avoided cost. We analyzed six currently available systems: hydrogen energy storage, flywheels, pumped hydroelectric storage, battery storage, compressed air storage, and superconducting magnetic energy storage, for energy and financial suitability. Potential wind turbine production is compared to consumption to determine the energy deficit or excess, which is fed into a model for each of the storage systems. We will discuss the advantages and disadvantages of each of the storage systems and their suitability for energy storage and peak shaving in this situation.

  17. Aquifer Thermal Energy Storage for Seasonal Thermal Energy Balance

    Science.gov (United States)

    Rostampour, Vahab; Bloemendal, Martin; Keviczky, Tamas

    2017-04-01

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

  18. Phase change energy storage for solar dynamic power systems

    Science.gov (United States)

    Chiaramonte, F. P.; Taylor, J. D.

    1992-01-01

    This paper presents the results of a transient computer simulation that was developed to study phase change energy storage techniques for Space Station Freedom (SSF) solar dynamic (SD) power systems. Such SD systems may be used in future growth SSF configurations. Two solar dynamic options are considered in this paper: Brayton and Rankine. Model elements consist of a single node receiver and concentrator, and takes into account overall heat engine efficiency and power distribution characteristics. The simulation not only computes the energy stored in the receiver phase change material (PCM), but also the amount of the PCM required for various combinations of load demands and power system mission constraints. For a solar dynamic power system in low earth orbit, the amount of stored PCM energy is calculated by balancing the solar energy input and the energy consumed by the loads corrected by an overall system efficiency. The model assumes an average 75 kW SD power system load profile which is connected to user loads via dedicated power distribution channels. The model then calculates the stored energy in the receiver and subsequently estimates the quantity of PCM necessary to meet peaking and contingency requirements. The model can also be used to conduct trade studies on the performance of SD power systems using different storage materials.

  19. Low temperature thermal-energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.S.; Christian, J.E.

    1979-03-01

    This report evaluates currently available techniques and estimated costs of low temperature thermal energy storage (TES) devices applicable to Integrated Community Energy Systems (ICES) installations serving communities ranging in size from approximately 3000 (characterized by an electrical load requirement of 2 MWe) to about 100,000 population (characterized by an electrical load requirement of 100 MWe). Thermal energy in the form of either hotness or coldness can be stored in a variety of media as sensible heat by virtue of a change in temperature of the material, or as latent heat of fusion in which the material changes from the liquid phase to the solid phase at essentially a constant temperature. Both types of material are considered for TES in ICES applications.

  20. Energy conversion & storage program. 1995 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Cairns, E.J.

    1996-06-01

    The 1995 annual report discusses laboratory activities in the Energy Conversion and Storage (EC&S) Program. The report is divided into three categories: electrochemistry, chemical applications, and material applications. Research performed in each category during 1995 is described. Specific research topics relate to the development of high-performance rechargeable batteries and fuel cells, the development of high-efficiency thermochemical processes for energy conversion, the characterization of new chemical processes and complex chemical species, and the study and application of novel materials related to energy conversion and transmission. Research projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials and deposition technologies, and advanced methods of analysis.

  1. Oriented nanostructures for energy conversion and storage.

    Science.gov (United States)

    Liu, Jun; Cao, Guozhong; Yang, Zhenguo; Wang, Donghai; Dubois, Dan; Zhou, Xiaodong; Graff, Gordon L; Pederson, Larry R; Zhang, Ji-Guang

    2008-01-01

    Recently, the role of nanostructured materials in addressing the challenges in energy and natural resources has attracted wide attention. In particular, oriented nanostructures demonstrate promising properties for energy harvesting, conversion, and storage. In this Review, we highlight the synthesis and application of oriented nanostructures in a few key areas of energy technologies, namely photovoltaics, batteries, supercapacitors, and thermoelectrics. Although the applications differ from field to field, a common fundamental challenge is to improve the generation and transport of electrons and ions. We highlight the role of high surface area to maximize the surface activity and discuss the importance of optimum dimension and architecture, controlled pore channels, and alignment of the nanocrystalline phase to optimize the transport of electrons and ions. Finally, we discuss the challenges in attaining integrated architectures to achieve the desired performance. Brief background information is provided for the relevant technologies, but the emphasis is focused mainly on the nanoscale effects of mostly inorganic-based materials and devices.

  2. Seneca Compressed Air Energy Storage (CAES) Project

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2012-11-30

    Compressed Air Energy Storage (CAES) is a hybrid energy storage and generation concept that has many potential benefits especially in a location with increasing percentages of intermittent wind energy generation. The objectives of the NYSEG Seneca CAES Project included: for Phase 1, development of a Front End Engineering Design for a 130MW to 210 MW utility-owned facility including capital costs; project financials based on the engineering design and forecasts of energy market revenues; design of the salt cavern to be used for air storage; draft environmental permit filings; and draft NYISO interconnection filing; for Phase 2, objectives included plant construction with a target in-service date of mid-2016; and for Phase 3, objectives included commercial demonstration, testing, and two-years of performance reporting. This Final Report is presented now at the end of Phase 1 because NYSEG has concluded that the economics of the project are not favorable for development in the current economic environment in New York State. The proposed site is located in NYSEG’s service territory in the Town of Reading, New York, at the southern end of Seneca Lake, in New York State’s Finger Lakes region. The landowner of the proposed site is Inergy, a company that owns the salt solution mining facility at this property. Inergy would have developed a new air storage cavern facility to be designed for NYSEG specifically for the Seneca CAES project. A large volume, natural gas storage facility owned and operated by Inergy is also located near this site and would have provided a source of high pressure pipeline quality natural gas for use in the CAES plant. The site has an electrical take-away capability of 210 MW via two NYSEG 115 kV circuits located approximately one half mile from the plant site. Cooling tower make-up water would have been supplied from Seneca Lake. NYSEG’s engineering consultant WorleyParsons Group thoroughly evaluated three CAES designs and concluded that any

  3. Long- vs. short-term energy storage technologies analysis : a life-cycle cost study : a study for the DOE energy storage systems program.

    Energy Technology Data Exchange (ETDEWEB)

    Schoenung, Susan M.; Hassenzahl, William V. (, - Advanced Energy Analysis, Piedmont, CA)

    2003-08-01

    This report extends an earlier characterization of long-duration and short-duration energy storage technologies to include life-cycle cost analysis. Energy storage technologies were examined for three application categories--bulk energy storage, distributed generation, and power quality--with significant variations in discharge time and storage capacity. More than 20 different technologies were considered and figures of merit were investigated including capital cost, operation and maintenance, efficiency, parasitic losses, and replacement costs. Results are presented in terms of levelized annual cost, $/kW-yr. The cost of delivered energy, cents/kWh, is also presented for some cases. The major study variable was the duration of storage available for discharge.

  4. Nanostructured conductive polymers for advanced energy storage.

    Science.gov (United States)

    Shi, Ye; Peng, Lele; Ding, Yu; Zhao, Yu; Yu, Guihua

    2015-10-07

    Conductive polymers combine the attractive properties associated with conventional polymers and unique electronic properties of metals or semiconductors. Recently, nanostructured conductive polymers have aroused considerable research interest owing to their unique properties over their bulk counterparts, such as large surface areas and shortened pathways for charge/mass transport, which make them promising candidates for broad applications in energy conversion and storage, sensors, actuators, and biomedical devices. Numerous synthetic strategies have been developed to obtain various conductive polymer nanostructures, and high-performance devices based on these nanostructured conductive polymers have been realized. This Tutorial review describes the synthesis and characteristics of different conductive polymer nanostructures; presents the representative applications of nanostructured conductive polymers as active electrode materials for electrochemical capacitors and lithium-ion batteries and new perspectives of functional materials for next-generation high-energy batteries, meanwhile discusses the general design rules, advantages, and limitations of nanostructured conductive polymers in the energy storage field; and provides new insights into future directions.

  5. Flywheel Energy Storage for Automotive Applications

    Directory of Open Access Journals (Sweden)

    Magnus Hedlund

    2015-09-01

    Full Text Available A review of flywheel energy storage technology was made, with a special focus on the progress in automotive applications. We found that there are at least 26 university research groups and 27 companies contributing to flywheel technology development. Flywheels are seen to excel in high-power applications, placing them closer in functionality to supercapacitors than to batteries. Examples of flywheels optimized for vehicular applications were found with a specific power of 5.5 kW/kg and a specific energy of 3.5 Wh/kg. Another flywheel system had 3.15 kW/kg and 6.4 Wh/kg, which can be compared to a state-of-the-art supercapacitor vehicular system with 1.7 kW/kg and 2.3 Wh/kg, respectively. Flywheel energy storage is reaching maturity, with 500 flywheel power buffer systems being deployed for London buses (resulting in fuel savings of over 20%, 400 flywheels in operation for grid frequency regulation and many hundreds more installed for uninterruptible power supply (UPS applications. The industry estimates the mass-production cost of a specific consumer-car flywheel system to be 2000 USD. For regular cars, this system has been shown to save 35% fuel in the U.S. Federal Test Procedure (FTP drive cycle.

  6. Energy storage systems program report for FY1996

    Energy Technology Data Exchange (ETDEWEB)

    Butler, P.C.

    1997-05-01

    Sandia National Laboratories, New Mexico, conducts the Energy Storage Systems Program, which is sponsored by the US Department of Energy`s Office of Utility Technologies. The goal of this program is to assist industry in developing cost-effective energy storage systems as a resource option by 2000. Sandia is responsible for the engineering analyses, contracted development, and testing of energy storage systems for stationary applications. This report details the technical achievements realized during fiscal year 1996.

  7. Comprehensive Monitoring for Heterogeneous Geographically Distributed Storage

    Energy Technology Data Exchange (ETDEWEB)

    Ratnikova, N. [Fermilab; Karavakis, E. [CERN; Lammel, S. [Fermilab; Wildish, T. [Princeton U.

    2015-12-23

    Storage capacity at CMS Tier-1 and Tier-2 sites reached over 100 Petabytes in 2014, and will be substantially increased during Run 2 data taking. The allocation of storage for the individual users analysis data, which is not accounted as a centrally managed storage space, will be increased to up to 40%. For comprehensive tracking and monitoring of the storage utilization across all participating sites, CMS developed a space monitoring system, which provides a central view of the geographically dispersed heterogeneous storage systems. The first prototype was deployed at pilot sites in summer 2014, and has been substantially reworked since then. In this paper we discuss the functionality and our experience of system deployment and operation on the full CMS scale.

  8. Power Optimization Distribution and Control Strategies of Multistage Vanadium Redox Flow Battery Energy Storage Systems%多级钒电池储能系统的功率优化分配及控制策略

    Institute of Scientific and Technical Information of China (English)

    李辉; 付博; 杨超; 赵斌; 唐显虎

    2013-01-01

    为了更好利用储能系统平抑大容量风电场功率波动,提出采用多级全钒液流电池(vanadium redox flow battery,VRB)储能的功率优化分配控制策略.首先,在建立VRB等效电路基础上,采用交直流变换器级联多重双向直流变换器作为VRB储能系统接口,分别建立了以稳定直流母线电压为目标的DC/AC变换器矢量控制策略,以电池荷电状态为约束的VRB充放电切换的DC/DC变换器双闭环控制策略.其次,以每级电池组的荷电状态值作为吞吐功率的优选目标,以外部端电压作为电池安全充放电的约束条件,提出多级VRB组的功率优化分配策略.最后,以不同荷电状态(state of charge,SOC)值下的2级VRB储能系统为例,对其在风速波动情况下的风电功率平抑效果以及各个储能单元充放电运行性能进行仿真,并与功率平均分配策略进行对比.结果表明,所提出的多级VRB储能系统功率优化分配和控制策略能很好的平滑风电功率波动,又能减少单台VRB组的充放电次数,并确保电池工作于安全运行区域.%In order to make better use of energy storage system to reduce the fluctuation of active power for large-scale wind farm,this paper proposes the optimization power distribution control strategies of the multistage vanadium redox flow battery (VRB) storage.Firstly,based on the equivalent circuit of a VRB and by using the interface of the DC/AC converter cascade multiple bi-directional DC/DC converter,a vector control strategy of DC/AC converter is presented to keep the stable DC bus voltage,and a double closed loop control strategy of DC/DC converter is established to switch charge-discharge style as a constraint of state of charge (SOC) on a single VRB.Secondly,by taking SOC value of each battery as priority target selection of output power,and by using the limit of external terminal voltage as the constraint conditions for battery safety charging and discharging,an optimization

  9. Seneca Compressed Air Energy Storage (CAES) Project

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2012-11-30

    Compressed Air Energy Storage (CAES) is a hybrid energy storage and generation concept that has many potential benefits especially in a location with increasing percentages of intermittent wind energy generation. The objectives of the NYSEG Seneca CAES Project included: for Phase 1, development of a Front End Engineering Design for a 130MW to 210 MW utility-owned facility including capital costs; project financials based on the engineering design and forecasts of energy market revenues; design of the salt cavern to be used for air storage; draft environmental permit filings; and draft NYISO interconnection filing; for Phase 2, objectives included plant construction with a target in-service date of mid-2016; and for Phase 3, objectives included commercial demonstration, testing, and two-years of performance reporting. This Final Report is presented now at the end of Phase 1 because NYSEG has concluded that the economics of the project are not favorable for development in the current economic environment in New York State. The proposed site is located in NYSEG’s service territory in the Town of Reading, New York, at the southern end of Seneca Lake, in New York State’s Finger Lakes region. The landowner of the proposed site is Inergy, a company that owns the salt solution mining facility at this property. Inergy would have developed a new air storage cavern facility to be designed for NYSEG specifically for the Seneca CAES project. A large volume, natural gas storage facility owned and operated by Inergy is also located near this site and would have provided a source of high pressure pipeline quality natural gas for use in the CAES plant. The site has an electrical take-away capability of 210 MW via two NYSEG 115 kV circuits located approximately one half mile from the plant site. Cooling tower make-up water would have been supplied from Seneca Lake. NYSEG’s engineering consultant WorleyParsons Group thoroughly evaluated three CAES designs and concluded that any

  10. Primary frequency regulation with Li-ion battery energy storage system: A case study for Denmark

    DEFF Research Database (Denmark)

    Swierczynski, Maciej Jozef; Stroe, Daniel Ioan; Stan, Ana-Irina

    2013-01-01

    and improving the predictability of the intermittent renewables but also of providing the ancillary services in the future energy markets. However, this is currently difficult to achieve due to high prices of the energy storage systems and difficulties with accurate prediction of the energy storage systems......Meeting ambitious goals of transition to distributed and environmentally-friendly renewable energy generation can be difficult to achieve without energy storage systems due to technical and economical challenges. Moreover, energy storage systems have a high potential of not only smoothing...... on the results obtained from accelerated lifetime testing. The developed Li­-ion battery lifetime model is later a base for the analyses of the economic profitability of the investment in the Li-ion battery energy storage system (BESS), which delivers the primary frequency regulation service on the Danish...

  11. Emerging electrochemical energy conversion and storage technologies.

    Science.gov (United States)

    Badwal, Sukhvinder P S; Giddey, Sarbjit S; Munnings, Christopher; Bhatt, Anand I; Hollenkamp, Anthony F

    2014-01-01

    Electrochemical cells and systems play a key role in a wide range of industry sectors. These devices are critical enabling technologies for renewable energy; energy management, conservation, and storage; pollution control/monitoring; and greenhouse gas reduction. A large number of electrochemical energy technologies have been developed in the past. These systems continue to be optimized in terms of cost, life time, and performance, leading to their continued expansion into existing and emerging market sectors. The more established technologies such as deep-cycle batteries and sensors are being joined by emerging technologies such as fuel cells, large format lithium-ion batteries, electrochemical reactors; ion transport membranes and supercapacitors. This growing demand (multi billion dollars) for electrochemical energy systems along with the increasing maturity of a number of technologies is having a significant effect on the global research and development effort which is increasing in both in size and depth. A number of new technologies, which will have substantial impact on the environment and the way we produce and utilize energy, are under development. This paper presents an overview of several emerging electrochemical energy technologies along with a discussion some of the key technical challenges.

  12. Emerging electrochemical energy conversion and storage technologies

    Directory of Open Access Journals (Sweden)

    Sukhvinder P.S. BADWAL

    2014-09-01

    Full Text Available Electrochemical cells and systems play a key role in a wide range of industry sectors. These devices are critical enabling technologies for renewable energy; energy management, conservation and storage; pollution control / monitoring; and greenhouse gas reduction. A large number of electrochemical energy technologies have been developed in the past. These systems continue to be optimized in terms of cost, life time and performance, leading to their continued expansion into existing and emerging market sectors. The more established technologies such as deep-cycle batteries and sensors are being joined by emerging technologies such as fuel cells, large format lithium-ion batteries, electrochemical reactors; ion transport membranes and supercapacitors. This growing demand (multi billion dollars for electrochemical energy systems along with the increasing maturity of a number of technologies is having a significant effect on the global research and development effort which is increasing in both in size and depth. A number of new technologies, which will have substantial impact on the environment and the way we produce and utilize energy, are under development. This paper presents an overview of several emerging electrochemical energy technologies along with a discussion some of the key technical challenges.

  13. Emerging electrochemical energy conversion and storage technologies

    Science.gov (United States)

    Badwal, Sukhvinder; Giddey, Sarbjit; Munnings, Christopher; Bhatt, Anand; Hollenkamp, Tony

    2014-09-01

    Electrochemical cells and systems play a key role in a wide range of industry sectors. These devices are critical enabling technologies for renewable energy; energy management, conservation and storage; pollution control / monitoring; and greenhouse gas reduction. A large number of electrochemical energy technologies have been developed in the past. These systems continue to be optimized in terms of cost, life time and performance, leading to their continued expansion into existing and emerging market sectors. The more established technologies such as deep-cycle batteries and sensors are being joined by emerging technologies such as fuel cells, large format lithium-ion batteries, electrochemical reactors; ion transport membranes and supercapacitors. This growing demand (multi billion dollars) for electrochemical energy systems along with the increasing maturity of a number of technologies is having a significant effect on the global research and development effort which is increasing in both in size and depth. A number of new technologies, which will have substantial impact on the environment and the way we produce and utilize energy, are under development. This paper presents an overview of several emerging electrochemical energy technologies along with a discussion some of the key technical challenges.

  14. bank as an energy storage device

    Directory of Open Access Journals (Sweden)

    Jurasz Jakub

    2017-01-01

    Full Text Available Renewable energy sources (RES are not the backbone of the Polish electricity generation sector. Even though the use of such resources is beneficial in terms of, e.g., CO2 emissions, current policy seems to create more and more obstacles hindering their further development on an industrial scale. The present paper proposes a simulation model of a hybrid micro power source coupled with a battery bank supplying a small group of households with an annual energy demand of 30 MWh. Results indicate that, for the selected site, a power source consisting of a wind turbine – 8kW, photovoltaic array – 9kW, water turbine – 2kW and 256 kWh energy storage capacity of a battery bank can be a reliable energy source. However, due to the intermittent nature of the selected energy sources there is still a need to remain on-grid in order to avoid excessive energy surpluses (in the case of an oversized system and deficits. This work opens several interesting directions for future studies, which will be discussed in later sections.

  15. A strategy for load balancing in distributed storage systems

    CERN Document Server

    CERN. Geneva

    2012-01-01

    Distributed storage systems are critical to the operation of the WLCG. These systems are not limited to fulfilling the long term storage requirements. They also serve data for computational analysis and other computational jobs. Distributed storage systems provide the ability to aggregate the storage and IO capacity of disks and tapes, but at the end of the day IO rate is still bound by the capabilities of the hardware, in particular the hard drives. Throughput of hard drives has increased dramatically over the decades, however for computational analysis IOPS is typically the limiting factor. To maximize return of investment, balancing IO load over available hardware is crucial. The task is made complicated by the common use of heterogeneous hardware and software environments that results from combining new and old hardware into a single storage system. This paper describes recent advances made in load balancing in the dCache distributed storage system. We describe a set of common requirements for load balan...

  16. High-temperature molten salt thermal energy storage systems

    Science.gov (United States)

    Petri, R. J.; Claar, T. D.; Tison, R. R.; Marianowski, L. G.

    1980-02-01

    The results of comparative screening studies of candidate molten carbonate salts as phase change materials (PCM) for advanced solar thermal energy storage applications at 540 to 870 C (1004 to 1600 F) and steam Rankine electric generation at 400 to 540 C (752 to 1004 F) are presented. Alkali carbonates are attractive as latent heat storage materials because of their relatively high storage capacity and thermal conductivity, low corrosivity, moderate cost, and safe and simple handling requirements. Salts were tested in 0.1 kWhr lab scale modules and evaluated on the basis of discharge heat flux, solidification temperature range, thermal cycling stability, and compatibility with containment materials. The feasibility of using a distributed network of high conductivity material to increase the heat flux through the layer of solidified salt was evaluated. The thermal performance of an 8 kWhr thermal energy storage (TES) module containing LiKCO3 remained very stable throughout 5650 hours and 130 charge/discharge cycles at 480 to 535 C (896 to 995 F). A TES utilization concept of an electrical generation peaking subsystem composed of a multistage condensing steam turbine and a TES subsystem with a separate power conversion loop was defined. Conceptual designs for a 100 MW sub e TES peaking system providing steam at 316 C, 427 C, and 454 C (600 F, 800 F, and 850 F) at 3.79 million Pa (550 psia) were developed and evaluated. Areas requiring further investigation have also been identified.

  17. Flexible Grouping for Enhanced Energy Utilization Efficiency in Battery Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    Weiping Diao

    2016-06-01

    Full Text Available As a critical subsystem in electric vehicles and smart grids, a battery energy storage system plays an essential role in enhancement of reliable operation and system performance. In such applications, a battery energy storage system is required to provide high energy utilization efficiency, as well as reliability. However, capacity inconsistency of batteries affects energy utilization efficiency dramatically; and the situation becomes more severe after hundreds of cycles because battery capacities change randomly due to non-uniform aging. Capacity mismatch can be solved by decomposing a cluster of batteries in series into several low voltage battery packs. This paper introduces a new analysis method to optimize energy utilization efficiency by finding the best number of batteries in a pack, based on capacity distribution, order statistics, central limit theorem, and converter efficiency. Considering both battery energy utilization and power electronics efficiency, it establishes that there is a maximum energy utilization efficiency under a given capacity distribution among a certain number of batteries, which provides a basic analysis for system-level optimization of a battery system throughout its life cycle. Quantitative analysis results based on aging data are illustrated, and a prototype of flexible energy storage systems is built to verify this analysis.

  18. Clusters, Quantum Confinement and Energy Storage

    Science.gov (United States)

    Connerade, Jean-Patrick

    One of the challenges posed by the demand for clean urban transportation is the compact and cyclically recoverable storage of energy in quantities sufficient for propulsion. Promising routes, such as the reversible insertion of Li+ ions inside solids for `rocking chair' batteries, require a deformable host material with no irreversibility. Such `soft' deformations are in general highly complex, but the compressibility of atoms or larger systems can be studied directly in situations with simpler symmetry. Thus, the search for `soft' materials leads one to consider certain types of cluster, as well as linear or nearly-spherical structures (chains of metallofullerenes, for example) whose deformations can be computed from the Schrodinger equation. Extended or `giant' atomic models allow one to construct compression-dilation cycles analogous in a rough sense to the Carnot cycle of classical thermodynamics. This simplified approach suggests that, even for idealised systems, there are constraints on the reversible storage and recovery of energy, and that (when applied to realistic structures) modelling based on such principles might help in the selection of appropriate materials.

  19. Storage Solutions for Power Quality Problems in Cyprus Electricity Distribution Network

    Directory of Open Access Journals (Sweden)

    Andreas Poullikkas

    2014-01-01

    Full Text Available In this work, a prediction of the effects of introducing energy storage systems on the network stability of the distribution network of Cyprus and a comparison in terms of cost with a traditional solution is carried out. In particular, for solving possible overvoltage problems, several scenarios of storage units' installation are used and compared with the alternative solution of extra cable connection between the node with the lowest voltage and the node with the highest voltage of the distribution network. For the comparison, a case study of a typical LV distribution feeder in the power system of Cyprus is used. The results indicated that the performance indicator of each solution depends on the type, the size and the position of installation of the storage unit. Also, as more storage units are installed the better the performance indicator and the more attractive is the investment in storage units to solve power quality problems in the distribution network. In the case where the technical requirements in voltage limitations according to distribution regulations are satisfied with one storage unit, the installation of an additional storage unit will only increase the final cost. The best solution, however, still remains the alternative solution of extra cable connection between the node with the lowest voltage and the node with the highest voltage of the distribution network, due to the lower investment costs compared to that of the storage units.

  20. Energy Policy Act of 2005 and Underground Storage Tanks (USTs)

    Science.gov (United States)

    The Energy Policy Act of 2005 significantly affected federal and state underground storage tank programs, required major changes to the programs, and is aimed at reducing underground storage tank releases to our environment.

  1. Distributed and Big Data Storage Management in Grid Computing

    Directory of Open Access Journals (Sweden)

    Ajay Kumar

    2012-07-01

    Full Text Available Big data storage management is one of the most challenging issues for Grid computing environments, since large amount of data intensive applications frequently involve a high degree of data access locality. Grid applications typically deal with large amounts of data. In traditional approaches high-performance computing consists dedicated servers that are used to data storage and data replication. In this paper we present a new mechanism for distributed and big data storage and resource discovery services. Here we proposed an architecture named Dynamic and Scalable Storage Management (DSSM architecture in grid environments. This allows in grid computing not only sharing the computational cycles, but also share the storage space. The storage can be transparently accessed from any grid machine, allowing easy data sharing among grid users and applications. The concept of virtual ids that, allows the creation of virtual spaces has been introduced and used. The DSSM divides all Grid Oriented Storage devices (nodes into multiple geographically distributed domains and to facilitate the locality and simplify the intra-domain storage management. Grid service based storage resources are adopted to stack simple modular service piece by piece as demand grows. To this end, we propose four axes that define: DSSM architecture and algorithms description, Storage resources and resource discovery into Grid service, Evaluate purpose prototype system, dynamically, scalability, and bandwidth, and Discuss results. Algorithms at bottom and upper level for standardization dynamic and scalable storage management, along with higher bandwidths have been designed.

  2. Cost analysis of energy storage systems for electric utility applications

    Energy Technology Data Exchange (ETDEWEB)

    Akhil, A. [Sandia National Lab., Albuquerque, NM (United States); Swaminathan, S.; Sen, R.K. [R.K. Sen & Associates, Inc., Bethesda, MD (United States)

    1997-02-01

    Under the sponsorship of the Department of Energy, Office of Utility Technologies, the Energy Storage System Analysis and Development Department at Sandia National Laboratories (SNL) conducted a cost analysis of energy storage systems for electric utility applications. The scope of the study included the analysis of costs for existing and planned battery, SMES, and flywheel energy storage systems. The analysis also identified the potential for cost reduction of key components.

  3. The expensive energy re-launches the electrokinetic storage; L'energie chere relance le stockage electrocinetique

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2006-09-15

    Progresses made in materials, mechanics and power electronic systems give a new competitiveness to flywheels and extends the range of their applications. This article presents the principle of electrokinetic storage flywheels with the different ways of improvement of this technology, and the three main applications in transportation systems, power distribution networks and large-scale energy storage systems. (J.S.)

  4. Reliability-oriented energy storage sizing in wind power systems

    DEFF Research Database (Denmark)

    Qin, Zian; Liserre, Marco; Blaabjerg, Frede;

    2014-01-01

    Energy storage can be used to suppress the power fluctuations in wind power systems, and thereby reduce the thermal excursion and improve the reliability. Since the cost of the energy storage in large power application is high, it is crucial to have a better understanding of the relationship...... between the size of the energy storage and the reliability benefit it can generate. Therefore, a reliability-oriented energy storage sizing approach is proposed for the wind power systems, where the power, energy, cost and the control strategy of the energy storage are all taken into account....... With the proposed approach, the computational effort is reduced and the impact of the energy storage system on the reliability of the wind power converter can be quantified....

  5. Northeastern Center for Chemical Energy Storage (NECCES)

    Energy Technology Data Exchange (ETDEWEB)

    Whittingham, M. Stanley [Stony Brook Univ., NY (United States)

    2015-07-31

    The chemical reactions that occur in batteries are complex, spanning a wide range of time and length scales from atomic jumps to the entire battery structure. The NECCES team of experimentalists and theorists made use of, and developed new methodologies to determine how model compound electrodes function in real time, as batteries are cycled. The team determined that kinetic control of intercalation reactions (reactions in which the crystalline structure is maintained) can be achieved by control of the materials morphology and explains and allows for the high rates of many intercalation reactions where the fundamental properties might indicate poor behavior in a battery application. The small overvoltage required for kinetic control is technically effective and economically feasible. A wide range of state-of-the-art operando techniques was developed to study materials under realistic battery conditions, which are now available to the scientific community. The team also investigated the key reaction steps in conversion electrodes, where the crystal structure is destroyed on reaction with lithium and rebuilt on lithium removal. These so-called conversion reactions have in principle much higher capacities, but were found to form very reactive discharge products that reduce the overall energy efficiency on cycling. It was found that by mixing either the anion, as in FeOF, or the cation, as in Cu1-yFeyF2, the capacity on cycling could be improved. The fundamental understanding of the reactions occurring in electrode materials gained in this study will allow for the development of much improved battery systems for energy storage. This will benefit the public in longer lived electronics, higher electric vehicle ranges at lower costs, and improved grid storage that also enables renewable energy supplies such as wind and solar.

  6. Assessment of Energy Storage Alternatives in the Puget Sound Energy System

    Energy Technology Data Exchange (ETDEWEB)

    Balducci, Patrick J.; Jin, Chunlian; Wu, Di; Kintner-Meyer, Michael CW; Leslie, Patrick; Daitch, Charles

    2013-12-12

    As part of an ongoing study co-funded by the Bonneville Power Administration, under its Technology Innovation Grant Program, and the U.S. Department of Energy, the Pacific Northwest National Laboratory (PNNL) has developed an approach and modeling tool for assessing the net benefits of using energy storage located close to the customer in the distribution grid to manage demand. PNNL in collaboration with PSE and Primus Power has evaluated the net benefits of placing a zinc bromide battery system at two locations in the PSE system (Baker River / Rockport and Bainbridge Island). Energy storage can provide a number of benefits to the utility through the increased flexibility it provides to the grid system. Applications evaluated in the assessment include capacity value, balancing services, arbitrage, distribution deferral and outage mitigation. This report outlines the methodology developed for this study and Phase I results.

  7. Wind energy management for smart grids with storage systems

    Energy Technology Data Exchange (ETDEWEB)

    Gasco, Manuel [Universidad de Alicante (Spain). Area de Ingenieria Electrica; Rios, Alberto [Universidad Europea de Madrid (Spain). Area de Ingenieria Electrica

    2012-07-01

    Increasing integration of wind energy into the power system makes the optimal management of different situations that can occur more and more important. The objective of the present study is to replace the power necessary for electrical feed when the wind resources are not available, and to make a continuous demand tracking of the power. The energy storage systems treated in this study are as follows: a fuel cell, flywheel, pump systems and turbine systems, compressed air systems, electrochemical cells, electric vehicles, supercapacitors and superconductors. As a result the maximum benefit of the smart grid is achieved and it includes coexistence of the energy storage systems described and integrated in the numerous microgrids which can form the distribution grid. The current capacity is observed in order to be able to manage the wind generation for short periods of time. This way it is possible to plan the production which would be adjusted to the variations through these storage systems allowing the systems to maintain their constant programming for the base plants, adjusting the variations in these systems in the short term. (orig.)

  8. Thermal energy storage - overview and specific insight into nitrate salts for sensible and latent heat storage.

    Science.gov (United States)

    Pfleger, Nicole; Bauer, Thomas; Martin, Claudia; Eck, Markus; Wörner, Antje

    2015-01-01

    Thermal energy storage (TES) is capable to reduce the demand of conventional energy sources for two reasons: First, they prevent the mismatch between the energy supply and the power demand when generating electricity from renewable energy sources. Second, utilization of waste heat in industrial processes by thermal energy storage reduces the final energy consumption. This review focuses mainly on material aspects of alkali nitrate salts. They include thermal properties, thermal decomposition processes as well as a new method to develop optimized salt systems.

  9. An Evaluation of Energy Storage Options for Nuclear Power

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, Justin L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bragg-Sitton, Shannon M. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Dufek, Eric J. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-06-01

    Energy supply, distribution, and demand are continuing to evolve as new generation sources come online and new appliances are installed. A larger percentage of the United States (U.S.) energy mix is provided by variable energy sources such as wind and solar each year, and distributed generation is becoming more common. In parallel, an evolution in consumer products such as electrical vehicles, information technology devices for residential and industrial applications, and appliances is changing how energy is consumed. As a result of these trends, nuclear power plants (NPPs) are being called upon to operate more flexibly than ever before. Furthermore, advanced nuclear power plants (A-NPPs) might operate as part of an electricity system that looks very different than when the current NPP fleet was constructed. A-NPPs face the possibility that they will need to operate in an environment where flexibility (e.g., fast ramping) is more highly valued than stability (e.g., baseload generation for conventional demand curves). The current fleet of NPPs is struggling to remain economical in competitive markets in an era of historically low natural gas prices and renewable sources with very low marginal costs. These factors, overlaid with an ambiguous national policy related to nuclear energy and a decision-making context that struggles with multi-decade capital investments, raise key questions and present significant challenges to the economics of nuclear power in the evolving grid. Multiple factors could improve the economics of A-NPPs, including: (1) minimizing the need for active safety systems, (2) minimizing adoption of one-off reactor designs, (3) establishing policies that credit low carbon emitting technologies, and (4) integrating energy storage technologies that increase revenue and reduce costs through a combination of ancillary services, market hedging, and reduced costs via stable operation. This report focuses on Item (4), containing an overview, synthesis, and

  10. The strain capacitor: A novel energy storage device

    OpenAIRE

    Pranoy Deb Shuvra; Shamus McNamara

    2014-01-01

    A novel electromechanical energy storage device is reported that has the potential to have high energy densities. It can efficiently store both mechanical strain energy and electrical energy in the form of an electric field between the electrodes of a strain-mismatched bilayer capacitor. When the charged device is discharged, both the electrical and mechanical energy are extracted in an electrical form. The charge-voltage profile of the device is suitable for energy storage applications since...

  11. Energy Conversion and Storage Requirements for Hybrid Electric Aircraft

    Science.gov (United States)

    Misra, Ajay

    2016-01-01

    Among various options for reducing greenhouse gases in future large commercial aircraft, hybrid electric option holds significant promise. In the hybrid electric aircraft concept, gas turbine engine is used in combination with an energy storage system to drive the fan that propels the aircraft, with gas turbine engine being used for certain segments of the flight cycle and energy storage system being used for other segments. The paper will provide an overview of various energy conversion and storage options for hybrid electric aircraft. Such options may include fuel cells, batteries, super capacitors, multifunctional structures with energy storage capability, thermoelectric, thermionic or a combination of any of these options. The energy conversion and storage requirements for hybrid electric aircraft will be presented. The role of materials in energy conversion and storage systems for hybrid electric aircraft will be discussed.

  12. Grid Converters for Stationary Battery Energy Storage Systems

    DEFF Research Database (Denmark)

    Trintis, Ionut

    to hours, rated at MW and MWh, battery energy storage systems are suitable and ecient solutions. Grid connection of the storage system can be done at dierent voltage levels, depending on the location and application scenario. For high power and energy ratings, increase in the battery and converter voltage...... was realized for a 100 kW active rectier to be used in a 6 kV battery energy storage test bench. In the second part, dierent solutions for power converters to interface energy storage units to medium voltage grid are given. A new modular multilevel converter concept is introduced, where the energy storage......-voltage 100 kW bidirectional grid converter, to be used in a high voltage battery energy storage test bench. The control structure proved to be stable without damping. The converter was tested in the test bench and the experimental results are presented. Multilevel converters are replacing the classical two...

  13. NASICON-Structured Materials for Energy Storage.

    Science.gov (United States)

    Jian, Zelang; Hu, Yong-Sheng; Ji, Xiulei; Chen, Wen

    2017-05-01

    The demand for electrical energy storage (EES) is ever increasing, which calls for better batteries. NASICON-structured materials represent a family of important electrodes due to its superior ionic conductivity and stable structures. A wide range of materials have been considered, where both vanadium-based and titanium-based materials are recommended as being of great interest. NASICON-structured materials are suitable for both the cathode and the anode, where the operation potential can be easily tuned by the choice of transition metal and/or polyanion group in the structure. NASICON-structured materials also represent a class of solid electrolytes, which are widely employed in all-solid-state ion batteries, all-solid-state air batteries, and hybrid batteries. NASICON-structured materials are reviewed with a focus on both electrode materials and solid-state electrolytes. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Safety flywheel. [using flexible materials energy storage

    Science.gov (United States)

    Schneider, R. T. (Inventor)

    1979-01-01

    An inertial energy storage device is disclosed which uses flywheel made of flexible material such as a twisted rope ring. A small number of the strands of the rope ring have a tensile strength that is lower than that of most of the other strands so that should any of these strands fail, they will begin to whiplash allowing such a failure to be detected and braked before a castastrophic failure occurs. This accomplished by the inclusion of glass tubes located around the periphery of the flywheel. The tubes are in communication with a braking fluid reservoir. The flywheel and glass tubes are enclosed within a vacuum-tight housing. The whiplashing of a broken strand breaks one or more glass tubes. This causes the housing to be flooded with the braking fluid thereby braking the rotation of the flywheel.

  15. Adiabatic Liquid Piston Compressed Air Energy Storage

    DEFF Research Database (Denmark)

    Petersen, Tage; Elmegaard, Brian; Pedersen, Allan Schrøder

    the mechanical energy into electricity at times of high electricity demand. Two such systems are currently in operation; one in Germany (Huntorf) and one in the USA (Macintosh, Alabama). In both cases, an underground cavern is used as a pressure vessel for the storage of the compressed air. Both systems...... are in the range of 100 MW electrical power output with several hours of production stored as compressed air. In this range, enormous volumes are required, which make underground caverns the only economical way to design the pressure vessel. Both systems use axial turbine compressors to compress air when charging......), but no such units are in operation at present. The CAES system investigated in this project uses a different approach to avoid compression heat loss. The system uses a pre-compressed pressure vessel full of air. A liquid is pumped into the bottom of the vessel when charging and the same liquid is withdrawn through...

  16. Seneca Compressed Air Energy Storage (CAES) Project

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2012-11-30

    This report provides a review and an analysis of potential environmental justice areas that could be affected by the New York State Electric & Gas (NYSEG) compress air energy storage (CAES) project and identifies existing environmental burden conditions on the area and evaluates additional burden of any significant adverse environmental impact. The review assesses the socioeconomic and demographic conditions of the area surrounding the proposed CAES facility in Schuyler County, New York. Schuyler County is one of 62 counties in New York. Schuyler County’s 2010 population of 18,343 makes it one of the least populated counties in the State (U.S. Census Bureau, 2010). This report was prepared for WorleyParsons by ERM and describes the study area investigated, methods and criteria used to evaluate this area, and the findings and conclusions from the evaluation.

  17. A Study on Energy Audit of a Cold Storage

    Directory of Open Access Journals (Sweden)

    Dr. N. Mukhopadhyay

    2015-04-01

    Full Text Available Energy consumption of a cold storage was measured for different storage temperatures. Suction temperature and pressure temperature of the compressor and working time of the compressor were determined to reach evaporator set up temperatures. An axial fan located back of the evaporator was used to distribute the cooled air into the cold store. An electrical heater was used to defrost. The compressor suction temperatures and discharge temperatures varied between 1.80 C - 070 C and 270 C - 350 C respectively. Condenser output temperature is varies 40 C - 100 C. Compressor suction pressure (p1 = 3.5 Kg/cm2 and discharge pressure (p2 = 10.5 Kg/cm2.

  18. Thermal performance and heat transport in aquifer thermal energy storage

    NARCIS (Netherlands)

    Sommer, W.T.; Doornenbal, P.J.; Drijver, B.C.; Gaans, van P.F.M.; Leusbrock, I.; Grotenhuis, J.T.C.; Rijnaarts, H.H.M.

    2014-01-01

    Aquifer thermal energy storage (ATES) is used for seasonal storage of large quantities of thermal energy. Due to the increasing demand for sustainable energy, the number of ATES systems has increased rapidly, which has raised questions on the effect of ATES systems on their surroundings as well as t

  19. Thermal energy storage for industrial waste heat recovery

    Science.gov (United States)

    Hoffman, H. W.; Kedl, R. J.; Duscha, R. A.

    1978-01-01

    Thermal energy storage systems designed for energy conservation through the recovery, storage, and reuse of industrial process waste heat are reviewed. Consideration is given to systems developed for primary aluminum, cement, the food processing industry, paper and pulp, and primary iron and steel. Projected waste-heat recovery and energy savings are listed for each category.

  20. A New Modular Multilevel Converter with Integrated Energy Storage

    DEFF Research Database (Denmark)

    Trintis, Ionut; Munk-Nielsen, Stig; Teodorescu, Remus

    2011-01-01

    This paper introduces a new modular converter with integrated energy storage based on the cascaded half-bridge modular multilevel converter with common DC bus. It represents a complete modular solution with power electronics and energy storage building blocks, for medium and high voltage...... in the future HVDC meshed grids. Its functionality and flexibility makes the converter independent on the energy storage unit characteristic. The converter concept with its basic functions and control schemes are described and evaluated in this paper....

  1. Impact of Wind Speed Correlation on the Operation of Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    Davril Mathieu

    2016-01-01

    Full Text Available Renewable resources technologies such as wind power currently demonstrate a worldwide popularity thanks to their environmental friendly status and their economic potential. The variability of the wind power output implies the use of practical solutions such as energy storage systems in order to retain the power system stability and reliability. The wind geographical correlation between different wind farms also impacts the system reliability. This paper studies the effects of the wind speed correlation level on the performance of the associated energy storage system (ESS. Wind correlated model using Weibull probability distribution and Nataf transformation is presented. Energy storage system model and energy management algorithm are developed. Both are applied to a modified IEEE-RTS power generation and load model. The case simulation results indicate that the wind speed correlation level between two wind farms impacts the power distribution inside energy storages and that it needs to be considered in order not to overestimate ESS benefits on the system.

  2. Energy storage - underground pumped storage / energy membrane; Energilager - nedgravet pumpelager / energimembran

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder Pedersen, A. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Hededal, O.; Foged, N. (Danmarks Tekniske Univ., DTU Byg. Institut for Byggeri og Anlaeg, Kgs. Lyngby (Denmark)) (and others)

    2010-06-15

    The project deals with a new idea where water from a nearby reservoir - sea, river or lake - via a pump/motor pressurizes a closed underground membrane, meaning that excessive electrical energy is stored as mechanical energy. Afterwards the stored energy is released by the obtained pressure and the amount of water will impel a turbine/generator. Hereby an underground pressurized pump storage can be established. The advantage by such type of pump storage is, that it can be placed, where there is no natural geological formations - high placed lake or alike. The conclusion and results after the completion of Phase 1 and 2 is that the expected losses in the soil layers where the energy is stored as potential energy will be approx. 100J/m{sub 3}. It is expected that the energy loss in the soil layer on a 50x50 m demo installation (performed in Phase 3) would constitute <0.5% of the total energy stored. An elongation of less the <2% of the LDPE membrane was measured in the experiments. This is a lot less than the 7% elongation that the membrane was exposed to during the testing at Danfoss, and further far below elongation of 500% that the supplier indicates. There were no changes on the membrane after the test. (Author)

  3. Multidimensional materials and device architectures for future hybrid energy storage

    Science.gov (United States)

    Lukatskaya, Maria R.; Dunn, Bruce; Gogotsi, Yury

    2016-09-01

    Electrical energy storage plays a vital role in daily life due to our dependence on numerous portable electronic devices. Moreover, with the continued miniaturization of electronics, integration of wireless devices into our homes and clothes and the widely anticipated `Internet of Things', there are intensive efforts to develop miniature yet powerful electrical energy storage devices. This review addresses the cutting edge of electrical energy storage technology, outlining approaches to overcome current limitations and providing future research directions towards the next generation of electrical energy storage devices whose characteristics represent a true hybridization of batteries and electrochemical capacitors.

  4. Seasonal storage of energy in solar heating

    Science.gov (United States)

    Braun, J. E.; Klein, S. A.; Mitchell, J. W.

    1981-01-01

    This paper focuses on several aspects of seasonal storage for space heating using water as the storage medium. The interrelationships between collector area, storage volume, and system performance are investigated using the transient simulation program TRNSYS. The situations for which seasonal storage is most promising are presented. Particular emphasis is placed upon design of seasonal storage systems. A design method is presented which is applicable for storage capacities ranging from a few days to seasonal storage. This design method, coupled with cost information, should be useful in assessing the economic viability of seasonal storage systems. Also investigated are the importance of the load heat exchanger size, tank insulation, collector slope, and year-to-year weather variations in system design.

  5. Integration of Distributed Energy Resources

    Directory of Open Access Journals (Sweden)

    Pushpendra Singh

    2014-01-01

    Full Text Available This Study proposes the feasibility of proposed restructured power system for the integration of distributed energy resources. Once the proposed power system network takes place, it will be able to provide opportunities for sustained economic growth. Main objectives of the proposed network are maximization of Distributed Generation (DGs penetration and decarbonization of electric utility. IEEE-14 bus test system with proposed configuration has been undertaken for MATLAB® Simulations, results shows that proposed power system configuration allows the operation of conventional energy generation and green energy generation efficiently. The results obtained from MATLAB ® simulations are compared with genetic algorithm based optimization approach.

  6. Optimizing Ice Thermal Storage to Reduce Energy Cost

    Science.gov (United States)

    Hall, Christopher L.

    Energy cost for buildings is an issue of concern for owners across the U.S. The bigger the building, the greater the concern. A part of this is due to the energy required to cool the building and the way in which charges are set when paying for energy consumed during different times of the day. This study will prove that designing ice thermal storage properly will minimize energy cost in buildings. The effectiveness of ice thermal storage as a means to reduce energy costs lies within transferring the time of most energy consumption from on-peak to off-peak periods. Multiple variables go into the equation of finding the optimal use of ice thermal storage and they are all judged with the final objective of minimizing monthly energy costs. This research discusses the optimal design of ice thermal storage and its impact on energy consumption, energy demand, and the total energy cost. A tool for optimal design of ice thermal storage is developed, considering variables such as chiller and ice storage sizes and charging and discharge times. The simulations take place in a four-story building and investigate the potential of Ice Thermal Storage as a resource in reducing and minimizing energy cost for cooling. The simulations test the effectiveness of Ice Thermal Storage implemented into the four-story building in ten locations across the United States.

  7. Scenario simulation based assessment of subsurface energy storage

    Science.gov (United States)

    Beyer, C.; Bauer, S.; Dahmke, A.

    2014-12-01

    Energy production from renewable sources such as solar or wind power is characterized by temporally varying power supply. The politically intended transition towards renewable energies in Germany („Energiewende") hence requires the installation of energy storage technologies to compensate for the fluctuating production. In this context, subsurface energy storage represents a viable option due to large potential storage capacities and the wide prevalence of suited geological formations. Technologies for subsurface energy storage comprise cavern or deep porous media storage of synthetic hydrogen or methane from electrolysis and methanization, or compressed air, as well as heat storage in shallow or moderately deep porous formations. Pressure build-up, fluid displacement or temperature changes induced by such operations may affect local and regional groundwater flow, geomechanical behavior, groundwater geochemistry and microbiology. Moreover, subsurface energy storage may interact and possibly be in conflict with other "uses" like drinking water abstraction or ecological goods and functions. An utilization of the subsurface for energy storage therefore requires an adequate system and process understanding for the evaluation and assessment of possible impacts of specific storage operations on other types of subsurface use, the affected environment and protected entities. This contribution presents the framework of the ANGUS+ project, in which tools and methods are developed for these types of assessments. Synthetic but still realistic scenarios of geological energy storage are derived and parameterized for representative North German storage sites by data acquisition and evaluation, and experimental work. Coupled numerical hydraulic, thermal, mechanical and reactive transport (THMC) simulation tools are developed and applied to simulate the energy storage and subsurface usage scenarios, which are analyzed for an assessment and generalization of the imposed THMC

  8. Optimal sizing of energy storage system for microgrids

    Indian Academy of Sciences (India)

    Babak Mozafari; Sirus Mohammadi

    2014-08-01

    Microgrids (MGs) are Low Voltage distribution networks comprising various distributed generators (DG), storage devices and controllable loads that can operate either interconnected or isolated from the main distribution grid as a controlled entity. Energy storage system (ESS) is a vital part of an MG. In this paper, a methodology is proposed for the optimal allocation and economic analysis of ESS in MGs on the basis of net present value (NPV). As the optimal operation of an MG strongly depends on the arrangement and allocation of its ESS, economic operation strategies and optimal allocation methods of the ESS devices are required for the MG. Self-adaptive Bee Swarm Optimization (SBSO) algorithm is applied to optimize the operation strategies and capacities of ESS in MGs in order to find maximal NPV, the generation schedule of ESS and distributed generation sources. This paper is to suggest, among those available ESS, the optimal sizes and types of them and their optimal arrangement, such that the total NPV achieved during the system operational lifetime period is maximized. After introducing the methodology, a case study is presented for illustration.

  9. Demonstration of EnergyNest thermal energy storage (TES) technology

    Science.gov (United States)

    Hoivik, Nils; Greiner, Christopher; Tirado, Eva Bellido; Barragan, Juan; Bergan, Pâl; Skeie, Geir; Blanco, Pablo; Calvet, Nicolas

    2017-06-01

    This paper presents the experimental results from the EnergyNest 2 × 500 kWhth thermal energy storage (TES) pilot system installed at Masdar Institute of Science & Technology Solar Platform. Measured data are shown and compared to simulations using a specially developed computer program to verify the stability and performance of the TES. The TES is based on a solid-state concrete storage medium (HEATCRETE®) with integrated steel tube heat exchangers cast into the concrete. The unique concrete recipe used in the TES has been developed in collaboration with Heidelberg Cement; this material has significantly higher thermal conductivity compared to regular concrete implying very effective heat transfer, at the same time being chemically stable up to 450 °C. The demonstrated and measured performance of the TES matches the predictions based on simulations, and proves the operational feasibility of the EnergyNest concrete-based TES. A further case study is analyzed where a large-scale TES system presented in this article is compared to two-tank indirect molten salt technology.

  10. Ferroelectric polymers for electrical energy storage

    Science.gov (United States)

    Claude, Jason W.

    The energy storage properties of vinylidene fluoride based fluoropolymers were explored. Energy density is a function of a materials permittivity and electrical breakdown strength. High values of each of these parameters are desirable for a high energy density and were explored in various fluoropolymer systems. Copolymers containing vinylidene fluoride (VDF), chlorofluoroethylene (CTFE), and trifluoroethylene (TrFE) were synthesized by a two-step approach beginning with the copolymerization of VDF and CTFE and the subsequent hydrogenation of the CTFE units to TrFE to create the terpolymer P(VDF-CTFE-TrFE). By changing the chemical composition of the fluoropolymers, the permittivity was varied from 12 to 50 due to changes in the crystal phase that converted the polymers from paraelectric to ferroelectric materials. The electrical breakdown mechanisms of a single copolymer composition of P(VDF-CTFE) was studied as a function of molecular weight and temperature. Energy density and breakdown strength increased as molecular weight increased and temperature decreased. An electromechanical breakdown mechanism was responsible for failure at 25°C while a thermal breakdown mechanism operated at -35°C which was below the glass transition of the material. In between at -15°C, a combination of the two mechanisms was found to operate. Electromechanical breakdown was also found to operate in a copolymer system with a fixed amount of VDF and varying amounts of TrFE and CTFE. The molecular weights were identical for all the polymers. Maxwell stress is the primary contributor to the electromechanical stress in polymers with a high amount the CTFE. Electrostrictive stress due to a crystal phase change at high electric fields is a major contributor to the electromechanical stress in polymers containing a high amount of TrFE. Energy density and electrical breakdown strength increased with increasing amounts of TrFE. Nanometer sized silica particles were incorporated into a P

  11. An interdisciplinary review of energy storage for communities: Challenges and perspectives

    DEFF Research Database (Denmark)

    Parra, David; Swierczynski, Maciej Jozef; Stroe, Daniel-Ioan

    2017-01-01

    Given the increasing penetration of renewable energy technologies as distributed generation embedded in the consumption centres, there is growing interest in energy storage systems located very close to consumers. These systems allow to increase the amount of renewable energy generation consumed ...

  12. Battery energy storage market feasibility study -- Expanded report

    Energy Technology Data Exchange (ETDEWEB)

    Kraft, S. [Frost and Sullivan, Mountain View, CA (United States); Akhil, A. [Sandia National Labs., Albuquerque, NM (United States). Energy Storage Systems Analysis and Development Dept.

    1997-09-01

    Under the sponsorship of the US Department of Energy`s Office of Utility Technologies, the Energy Storage Systems Analysis and Development Department at Sandia National Laboratories (SNL) contracted Frost and Sullivan to conduct a market feasibility study of energy storage systems. The study was designed specifically to quantify the battery energy storage market for utility applications. This study was based on the SNL Opportunities Analysis performed earlier. Many of the groups surveyed, which included electricity providers, battery energy storage vendors, regulators, consultants, and technology advocates, viewed battery storage as an important technology to enable increased use of renewable energy and as a means to solve power quality and asset utilization issues. There are two versions of the document available, an expanded version (approximately 200 pages, SAND97-1275/2) and a short version (approximately 25 pages, SAND97-1275/1).

  13. Identification of energy storage rate components. Theoretical and experimental approach

    Energy Technology Data Exchange (ETDEWEB)

    Oliferuk, W; Maj, M, E-mail: wolif@ippt.gov.p [Fundamental Technological Research, Polish Academy of Sciences, Pawinskiego 5b, 02-106 Warszawa (Poland)

    2010-07-01

    The subject of the present paper is decomposition of energy storage rate into terms related to different mode of deformation. The stored energy is the change in internal energy due to plastic deformation after specimen unloading. Hence, this energy describes the state of the cold-worked material. Whereas, the ratio of the stored energy increment to the appropriate increment of plastic work is the measure of energy conversion process. This ratio is called the energy storage rate. Experimental results show that the energy storage rate is dependent on plastic strain. This dependence is influenced by different microscopic deformation mechanisms. It has been shown that the energy storage rate can be presented as a sum of particular components. Each of them is related to the separate internal microscopic mechanism. Two of the components are identified. One of them is the storage rate of statistically stored dislocation energy related to uniform deformation. Another one is connected with non-uniform deformation at the grain level. It is the storage rate of the long range stresses energy and geometrically necessary dislocation energy. The maximum of energy storage rate, that appeared at initial stage of plastic deformation is discussed in terms of internal micro-stresses.

  14. Rebuilding for Array Codes in Distributed Storage Systems

    CERN Document Server

    Wang, Zhiying; Bruck, Jehoshua

    2010-01-01

    In distributed storage systems that use coding, the issue of minimizing the communication required to rebuild a storage node after a failure arises. We consider the problem of repairing an erased node in a distributed storage system that uses an EVENODD code. EVENODD codes are maximum distance separable (MDS) array codes that are used to protect against erasures, and only require XOR operations for encoding and decoding. We show that when there are two redundancy nodes, to rebuild one erased systematic node, only 3/4 of the information needs to be transmitted. Interestingly, in many cases, the required disk I/O is also minimized.

  15. Superconducting Magnetic Energy Storage:. Conventional and Trapped Field

    Science.gov (United States)

    Rabinowitz, Mario

    Superconducting magnetic energy storage (SMES) is a most efficient system for energy storage because it stores energy directly in electrical form. The SMES concept is described and analyzed with an examination of its economic viability. The impact of high-temperature supeconductivity on SMES is explored, and a trapped energy storage (TES) innovation that may have beneficial technical and economic ramifications is introduced. In addition to presenting a broad overview, this paper may be of help to those making an evaluation of the potential impact of SMES/TES on the development of new energy sources, and to determine for which energy sources it is most appropriate.

  16. Nanostructured metal sulfides for energy storage.

    Science.gov (United States)

    Rui, Xianhong; Tan, Huiteng; Yan, Qingyu

    2014-09-07

    Advanced electrodes with a high energy density at high power are urgently needed for high-performance energy storage devices, including lithium-ion batteries (LIBs) and supercapacitors (SCs), to fulfil the requirements of future electrochemical power sources for applications such as in hybrid electric/plug-in-hybrid (HEV/PHEV) vehicles. Metal sulfides with unique physical and chemical properties, as well as high specific capacity/capacitance, which are typically multiple times higher than that of the carbon/graphite-based materials, are currently studied as promising electrode materials. However, the implementation of these sulfide electrodes in practical applications is hindered by their inferior rate performance and cycling stability. Nanostructures offering the advantages of high surface-to-volume ratios, favourable transport properties, and high freedom for the volume change upon ion insertion/extraction and other reactions, present an opportunity to build next-generation LIBs and SCs. Thus, the development of novel concepts in material research to achieve new nanostructures paves the way for improved electrochemical performance. Herein, we summarize recent advances in nanostructured metal sulfides, such as iron sulfides, copper sulfides, cobalt sulfides, nickel sulfides, manganese sulfides, molybdenum sulfides, tin sulfides, with zero-, one-, two-, and three-dimensional morphologies for LIB and SC applications. In addition, the recently emerged concept of incorporating conductive matrices, especially graphene, with metal sulfide nanomaterials will also be highlighted. Finally, some remarks are made on the challenges and perspectives for the future development of metal sulfide-based LIB and SC devices.

  17. Thermal energy storage. [by means of chemical reactions

    Science.gov (United States)

    Grodzka, P. G.

    1975-01-01

    The principles involved in thermal energy storage by sensible heat, chemical potential energy, and latent heat of fusion are examined for the purpose of evolving selection criteria for material candidates in the low ( 0 C) and high ( 100 C) temperature ranges. The examination identifies some unresolved theoretical considerations and permits a preliminary formulation of an energy storage theory. A number of candidates in the low and high temperature ranges are presented along with a rating of candidates or potential candidates. A few interesting candidates in the 0 to 100 C region are also included. It is concluded that storage by means of reactions whose reversibility can be controlled either by product removal or by catalytic means appear to offer appreciable advantages over storage with reactions whose reversability cannot be controlled. Among such advantages are listed higher heat storage capacities and more favorable options regarding temperatures of collection, storage, and delivery. Among the disadvantages are lower storage efficiencies.

  18. Grid regulation services for energy storage devices based on grid frequency

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, Richard M.; Hammerstrom, Donald J.; Kintner-Meyer, Michael C. W.; Tuffner, Francis K.

    2017-09-05

    Disclosed herein are representative embodiments of methods, apparatus, and systems for charging and discharging an energy storage device connected to an electrical power distribution system. In one exemplary embodiment, a controller monitors electrical characteristics of an electrical power distribution system and provides an output to a bi-directional charger causing the charger to charge or discharge an energy storage device (e.g., a battery in a plug-in hybrid electric vehicle (PHEV)). The controller can help stabilize the electrical power distribution system by increasing the charging rate when there is excess power in the electrical power distribution system (e.g., when the frequency of an AC power grid exceeds an average value), or by discharging power from the energy storage device to stabilize the grid when there is a shortage of power in the electrical power distribution system (e.g., when the frequency of an AC power grid is below an average value).

  19. Energy Storage Technology Development for Space Exploration

    Science.gov (United States)

    Mercer, Carolyn R.; Jankovsky, Amy L.; Reid, Concha M.; Miller, Thomas B.; Hoberecht, Mark A.

    2011-01-01

    The National Aeronautics and Space Administration is developing battery and fuel cell technology to meet the expected energy storage needs of human exploration systems. Improving battery performance and safety for human missions enhances a number of exploration systems, including un-tethered extravehicular activity suits and transportation systems including landers and rovers. Similarly, improved fuel cell and electrolyzer systems can reduce mass and increase the reliability of electrical power, oxygen, and water generation for crewed vehicles, depots and outposts. To achieve this, NASA is developing non-flow-through proton-exchange-membrane fuel cell stacks, and electrolyzers coupled with low permeability membranes for high pressure operation. The primary advantage of this technology set is the reduction of ancillary parts in the balance-of-plant fewer pumps, separators and related components should result in fewer failure modes and hence a higher probability of achieving very reliable operation, and reduced parasitic power losses enable smaller reactant tanks and therefore systems with lower mass and volume. Key accomplishments over the past year include the fabrication and testing of several robust, small-scale non-flow-through fuel cell stacks that have demonstrated proof-of-concept. NASA is also developing advanced lithium-ion battery cells, targeting cell-level safety and very high specific energy and energy density. Key accomplishments include the development of silicon composite anodes, lithiatedmixed- metal-oxide cathodes, low-flammability electrolytes, and cell-incorporated safety devices that promise to substantially improve battery performance while providing a high level of safety.

  20. Day-Ahead Scheduling of a Photovoltaic Plant by the Energy Management of a Storage System

    DEFF Research Database (Denmark)

    Marinelli, Mattia; Sossan, Fabrizio; Isleifsson, Fridrik Rafn

    2013-01-01

    by a proper management of the storage. Due to forecast inaccuracies, the energy manager controls the storage in order to ensure that the plan for hourly energy production is respected, minimizing the storage itself usage. The experimental study is carried out in SYSLAB, a distributed power system test......The paper discusses and describes a system for energy management of a 10 kW PV plant coupled with a 15 kW - 190 kWh storage system. The overall idea is, by knowing the meteorological forecast for the next 24h, to dispatch the PV system and to be able to grant the scheduled hourly energy profile...... facility at DTU Risø Campus and part of PowerLabDK. Both the PV and the storage are connected to the local network and are fully controllable through the SCADA system. The control management and the models are implemented in Matlab-Simulink, which can be interfaced with SYSLAB....

  1. First assessment of continental energy storage in CMIP5 simulations

    Science.gov (United States)

    Cuesta-Valero, Francisco José; García-García, Almudena; Beltrami, Hugo; Smerdon, Jason E.

    2016-05-01

    Although much of the energy gained by the climate system over the last century has been stored in the oceans, continental energy storage remains important to estimate the Earth's energy imbalance and also because crucial positive climate feedback processes such as soil carbon and permafrost stability depend on continental energy storage. Here for the first time, 32 general circulation model simulations from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) are examined to assess their ability to characterize the continental energy storage. Results display a consistently lower magnitude of continental energy storage in CMIP5 simulations than the estimates from geothermal data. A large range in heat storage is present across the model ensemble, which is largely explained by the substantial differences in the bottom boundary depths used in each land surface component.

  2. Metal sulfide electrodes and energy storage devices thereof

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Yet-Ming; Woodford, William Henry; Li, Zheng; Carter, W. Craig

    2017-02-28

    The present invention generally relates to energy storage devices, and to metal sulfide energy storage devices in particular. Some aspects of the invention relate to energy storage devices comprising at least one flowable electrode, wherein the flowable electrode comprises an electroactive metal sulfide material suspended and/or dissolved in a carrier fluid. In some embodiments, the flowable electrode further comprises a plurality of electronically conductive particles suspended and/or dissolved in the carrier fluid, wherein the electronically conductive particles form a percolating conductive network. An energy storage device comprising a flowable electrode comprising a metal sulfide electroactive material and a percolating conductive network may advantageously exhibit, upon reversible cycling, higher energy densities and specific capacities than conventional energy storage devices.

  3. Optimal Power Flow in Microgrids with Energy Storage

    DEFF Research Database (Denmark)

    Levron, Yoash; Guerrero, Josep M.; Beck, Yuval

    2013-01-01

    , these works assume flat, highly simplified network models, which overlook the physical connectivity. This work proposes an optimal power flow solution that considers the entire system: the storage device limits, voltages limits, currents limits, and power limits. The power network may be arbitrarily complex......Energy storage may improve power management in microgrids that include renewable energy sources. The storage devices match energy generation to consumption, facilitating a smooth and robust energy balance within the microgrid. This paper addresses the optimal control of the microgrid’s energy...... storage devices. Stored energy is controlled to balance power generation of renewable sources to optimize overall power consumption at the microgrid point of common coupling. Recent works emphasize constraints imposed by the storage device itself, such as limited capacity and internal losses. However...

  4. Foresight Study on Transport, Distribution, Storage and End Use of Energy; Estudio de Propsectiva Transporte, Distribucion, Almacenamiento y Uso Final de la Energia

    Energy Technology Data Exchange (ETDEWEB)

    Claver Cabrero, A.; Cabrera Jimenez, J.A.

    2001-07-01

    The Observatorio de Prospectiva Tecnologica Industrial (OPTI) is a Foundation supported by the Ministry of Industry and Energy (MINER) and has as main objective to provide a basic information and knowledge on technology evolution. This information will be accessible to the Administration and to the Companies and can be taking into account in planning and decision making of technology policies. Ciemat is member of OPTI and also is the organism in charge of the actions in the Energy sector. CIEMAT has the responsibility on the realisation of the sector studies to get in three years (1998 to 2001) a future vision on critical technology topics. The OPTI integrated strategic plan undertake the analysis of other seven technology sectors, with the same criteria and methodological aspects. Delphi method was used for the realization of the studies using a survey conducted in two rounds with a questionnaire to check the experts opinion. The timeframe of the studies was defined from 1999 to 2015. The study presented in this document has been performed by CIEMAT in the third stage of the OPTI activities. The main goal behind this study is to identify spanish position and existing barriers technological development together with recommended measures to be taken in order to facilitate their future performance. This basic information can be used by different S AND T actors as input to develop technology and innovation policies. also, taken into account actual energetic situation with a foreseeable demand increase and fossil fuel dependence, the results of this study can be considered of general main interest. (Author)

  5. The Role of Energy Storage in Commercial Building

    Energy Technology Data Exchange (ETDEWEB)

    Kintner-Meyer, Michael CW; Subbarao, Krishnappa; Prakash Kumar, Nirupama; Bandyopadhyay, Gopal K.; Finley, C.; Koritarov, V. S.; Molburg, J. C.; Wang, J.; Zhao, Fuli; Brackney, L.; Florita, A. R.

    2010-09-30

    Motivation and Background of Study This project was motivated by the need to understand the full value of energy storage (thermal and electric energy storage) in commercial buildings, the opportunity of benefits for building operations and the potential interactions between a building and a smart grid infrastructure. On-site or local energy storage systems are not new to the commercial building sector; they have been in place in US buildings for decades. Most building-scale storage technologies are based on thermal or electrochemical storage mechanisms. Energy storage technologies are not designed to conserve energy, and losses associated with energy conversion are inevitable. Instead, storage provides flexibility to manage load in a building or to balance load and generation in the power grid. From the building owner's perspective, storage enables load shifting to optimize energy costs while maintaining comfort. From a grid operations perspective, building storage at scale could provide additional flexibility to grid operators in managing the generation variability from intermittent renewable energy resources (wind and solar). To characterize the set of benefits, technical opportunities and challenges, and potential economic values of storage in a commercial building from both the building operation's and the grid operation's view-points is the key point of this project. The research effort was initiated in early 2010 involving Argonne National Laboratory (ANL), the National Renewable Energy Laboratory (NREL), and Pacific Northwest National Laboratory (PNNL) to quantify these opportunities from a commercial buildings perspective. This report summarizes the early discussions, literature reviews, stakeholder engagements, and initial results of analyses related to the overall role of energy storage in commercial buildings. Beyond the summary of roughly eight months of effort by the laboratories, the report attempts to substantiate the importance of

  6. U.S. Department of Energy thermal energy storage research activities review: 1989 Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, H.W. [ed.] [PAI Corp., Oak Ridge, TN (United States); Tomlinson, J.J. [ed.] [Oak Ridge National Lab., TN (United States)

    1989-03-01

    Thermal Energy Storage (TES) offers the opportunity for the recovery and re-use of heat currently rejected to the ambient environment. Further, through the ability of TES to match an energy supply with a thermal energy demand, TES increases efficiencies of energy systems and improves capacity factors of power plants. The US Department of Energy has been the leader in TES research, development, and demonstration since recognition in 1976 of the need for fostering energy conservation as a component of the national energy budget. The federal program on TES R and D is the responsibility of the Office of Energy Storage and Distribution within the US Department of Energy (DOE). The overall program is organized into three program areas: diurnal--relating primarily to lower temperature heat for use in residential and commercial buildings on a daily cycle; industrial--relating primarily to higher temperature heat for use in industrial and utility processes on an hourly to daily cycle; seasonal--relating primarily to lower temperature heat or chill for use in residential complexes (central supply as for apartments or housing developments), commercial (light manufacturing, processing, or retail), and industrial (space conditioning) on a seasonal to annual cycle. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  7. The Carbon Nanotube Fibers for Optoelectric Conversion and Energy Storage

    Directory of Open Access Journals (Sweden)

    Yongfeng Luo

    2014-01-01

    Full Text Available This review summarizes recent studies on carbon nanotube (CNT fibers for weavable device of optoelectric conversion and energy storage. The intrinsic properties of individual CNTs make the CNT fibers ideal candidates for optoelectric conversion and energy storage. Many potential applications such as solar cell, supercapacitor, and lithium ion battery have been envisaged. The recent advancement in CNT fibers for optoelectric conversion and energy storage and the current challenge including low energy conversion efficiency and low stability and future direction of the energy fiber have been finally summarized in this paper.

  8. Energy storage systems program report for FY97

    Energy Technology Data Exchange (ETDEWEB)

    Butler, P.C.

    1998-08-01

    Sandia National Laboratories, New Mexico, conducts the Energy Storage Systems Program, which is sponsored by the US Department of Energy`s Office of Utility Technologies. The goal of this program is to collaborate with industry in developing cost-effective electric energy storage systems for many high-value stationary applications. Sandia National Laboratories is responsible for the engineering analyses, contracted development, and testing of energy storage components and systems. This report details the technical achievements realized during fiscal year 1997. 46 figs., 20 tabs.

  9. Advanced Space Power Systems (ASPS): Advanced Energy Storage Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The development of high specific energy devices will enable NASA’s future robotic and human-exploration missions.  The need for advances in energy storage...

  10. Innovative applications of energy storage in a restructured electricity marketplace : Phase III final report : a study for the DOE Energy Storage Systems Program.

    Energy Technology Data Exchange (ETDEWEB)

    Eyer, James M. (Distributed Utility Associates, Livermore, CA); Erdman, Bill (Distributed Utility Associates, Livermore, CA); Iannucci, Joseph J., Jr. (, . Distributed Utility Associates, Livermore, CA)

    2005-03-01

    This report describes Phase III of a project entitled Innovative Applications of Energy Storage in a Restructured Electricity Marketplace. For this study, the authors assumed that it is feasible to operate an energy storage plant simultaneously for two primary applications: (1) energy arbitrage, i.e., buy-low-sell-high, and (2) to reduce peak loads in utility ''hot spots'' such that the utility can defer their need to upgrade transmission and distribution (T&D) equipment. The benefits from the arbitrage plus T&D deferral applications were estimated for five cases based on the specific requirements of two large utilities operating in the Eastern U.S. A number of parameters were estimated for the storage plant ratings required to serve the combined application: power output (capacity) and energy discharge duration (energy storage). In addition to estimating the various financial expenditures and the value of electricity that could be realized in the marketplace, technical characteristics required for grid-connected distributed energy storage used for capacity deferral were also explored.

  11. Hybrid radical energy storage device and method of making

    Energy Technology Data Exchange (ETDEWEB)

    Gennett, Thomas; Ginley, David S.; Braunecker, Wade; Ban, Chunmei; Owczarczyk, Zbyslaw

    2016-04-26

    Hybrid radical energy storage devices, such as batteries or electrochemical devices, and methods of use and making are disclosed. Also described herein are electrodes and electrolytes useful in energy storage devices, for example, radical polymer cathode materials and electrolytes for use in organic radical batteries.

  12. Thermal energy storage subsystems (a collection of quarterly reports)

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    Five quarterly reports are presented, covering the progress made in the development, fabrication, and delivery of three Thermal Energy Storage Subsystems. The design, development, and progress toward the delivery of three subsystems are discussed. The subsystem uses a salt hydrate mixture for thermal energy storage. Included are the program schedules, technical data, and other program activities from October 1, 1976 through December 31, 1977.

  13. Energy storage technology - Environmental implications of large scale utilization

    Science.gov (United States)

    Krupka, M. C.; Moore, J. E.; Keller, W. E.; Baca, G. A.; Brasier, R. I.; Bennett, W. S.

    Environmental effects are identified for several energy storage technologies including advanced lead-acid battery, compressed air, underground pumped hydroelectric, flywheel, superconducting magnet, and various thermal systems. A preliminary study on fuel cell technology is also reported. New applications for energy storage technologies and the additional costs of controls to be used for mitigation of specific impacts are briefly discussed.

  14. Nanostructured graphene nanoplatelets for energy storage applications

    Science.gov (United States)

    Monga, Anchita

    There is an increasing demand for high performance compact batteries for diverse applications ranging from portable electronics to electric automotive vehicles. This need has driven the direction of research towards newer materials, improved synthesis and architectured assembly. This research addresses the gravimetric and volumetric density challenges as well as the cost issues faced by energy storage devices by developing structured graphitic materials, aiming at better electrochemical performance, improved energy density and reduced cost. The few layer graphene nanoplatelets (GnP) used in this study can be produced from natural graphite in thicknesses from 1-10 nm and in widths from 0.3 to 50 microns via an acid intercalation/thermal exfoliation process. The GnP serves as an inexpensive alternative to carbon nanotubes and single graphene sheets. The ability to nanostructure GnP and tailor its inherent properties for lithium storage and electrical conductivity, allows it to be used for customized applications in three different lithium ion battery components viz., active anode material, current collector and conducting additive. Metal nanoparticle doped GnP in which nanosized metal particles are coated onto the GnP basal surface, have been assembled to make a 'pillared' nanostructure in which the particles maintain a fixed distance between adjacent GnPs facilitating improved transport and enhanced lithium storage capacity, especially at faster charge rates. Graphene nanoplatelets synthesized with different sizes of metal nanoparticles effectively create a nano-architectured GnP multilayer assembly with flexible interlayer spacing. The creation of a lithium ion battery anode with controllable GnP interlayer spacing facilitates lithium ion diffusion through the electrode, and this in turn leads to improved transport and enhanced capacity. Graphene nanoplatelets are also intrinsically excellent electrical conductors, which can be assembled into continuous conductive

  15. Evaluation of Representative Smart Grid Investment Grant Project Technologies: Thermal Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Tuffner, Francis K.; Bonebrake, Christopher A.

    2012-02-14

    This document is one of a series of reports estimating the benefits of deploying technologies similar to those implemented on the Smart Grid Investment Grant (SGIG) projects. Four technical reports cover the various types of technologies deployed in the SGIG projects, distribution automation, demand response, energy storage, and renewables integration. A fifth report in the series examines the benefits of deploying these technologies on a national level. This technical report examines the impacts of energy storage technologies deployed in the SGIG projects.

  16. Metal oxide-carbon composites for energy conversion and storage

    Science.gov (United States)

    Perera, Sanjaya Dulip

    The exponential growth of the population and the associated energy demand requires the development of new materials for sustainable energy conversion and storage. Expanding the use of renewable energy sources to generate electricity is still not sufficient enough to fulfill the current energy demand. Electricity generation by wind and solar is the most promising alternative energy resources for coal and oil. The first part of the dissertation addresses an alternative method for preparing TiO2 nanotube based photoanodes for DSSCs. This would involve smaller diameter TiO2 nanotubes (˜10 nm), instead of nanoparticles or electrochemically grown larger nanotubes. Moreover, TiO2 nanotube-graphene based photocatalysts were developed to treat model pollutants. In the second part of this dissertation, the development of electrical energy storage systems, which provide high storage capacity and power output using low cost materials are discussed. Among different types of energy storage systems, batteries are the most convenient method to store electrical energy. However, the low power performance of batteries limits the application in different types of electrical energy storage. The development of electrical energy storage systems, which provide high storage capacity and power output using low cost materials are discussed.

  17. Specific systems studies of battery energy storage for electric utilities

    Energy Technology Data Exchange (ETDEWEB)

    Akhil, A.A.; Lachenmeyer, L. [Sandia National Labs., Albuquerque, NM (United States); Jabbour, S.J. [Decision Focus, Inc., Mountain View, CA (United States); Clark, H.K. [Power Technologies, Inc., Roseville, CA (United States)

    1993-08-01

    Sandia National Laboratories, New Mexico, conducts the Utility Battery Storage Systems Program, which is sponsored by the US Department of Energy`s Office of Energy Management. As a part of this program, four utility-specific systems studies were conducted to identify potential battery energy storage applications within each utility network and estimate the related benefits. This report contains the results of these systems studies.

  18. Secondary batteries with multivalent ions for energy storage.

    Science.gov (United States)

    Xu, Chengjun; Chen, Yanyi; Shi, Shan; Li, Jia; Kang, Feiyu; Su, Dangsheng

    2015-09-14

    The use of electricity generated from clean and renewable sources, such as water, wind, or sunlight, requires efficiently distributed electrical energy storage by high-power and high-energy secondary batteries using abundant, low-cost materials in sustainable processes. American Science Policy Reports state that the next-generation "beyond-lithium" battery chemistry is one feasible solution for such goals. Here we discover new "multivalent ion" battery chemistry beyond lithium battery chemistry. Through theoretic calculation and experiment confirmation, stable thermodynamics and fast kinetics are presented during the storage of multivalent ions (Ni(2+), Zn(2+), Mg(2+), Ca(2+), Ba(2+), or La(3+) ions) in alpha type manganese dioxide. Apart from zinc ion battery, we further use multivalent Ni(2+) ion to invent another rechargeable battery, named as nickel ion battery for the first time. The nickel ion battery generally uses an alpha type manganese dioxide cathode, an electrolyte containing Ni(2+) ions, and Ni anode. The nickel ion battery delivers a high energy density (340 Wh kg(-1), close to lithium ion batteries), fast charge ability (1 minute), and long cycle life (over 2200 times).

  19. Saline Cavern Adiabatic Compressed Air Energy Storage Using Sand as Heat Storage Material

    Directory of Open Access Journals (Sweden)

    Martin Haemmerle

    2017-03-01

    Full Text Available Adiabatic compressed air energy storage systems offer large energy storage capacities and power outputs beyond 100MWel. Salt production in Austria produces large caverns which are able to hold pressure up to 100 bar, thus providing low cost pressurized air storage reservoirs for adiabatic compressed air energy storage plants. In this paper the results of a feasibility study is presented, which was financed by the Austrian Research Promotion Agency, with the objective to determine the adiabatic compressed air energy storage potential of Austria’s salt caverns. The study contains designs of realisable plants with capacities between 10 and 50 MWel, applying a high temperature energy storage system currently developed at the Institute for Energy Systems and Thermodynamics in Vienna. It could be shown that the overall storage potential of Austria’s salt caverns exceeds a total of 4GWhel in the year 2030 and, assuming an adequate performance of the heat exchanger, that a 10MWel adiabatic compressed air energy storage plant in Upper Austria is currently feasible using state of the art thermal turbomachinery which is able to provide a compressor discharge temperature of 400 °C.

  20. Thermal energy storage for solar applications: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Wyman, C.

    1979-03-01

    This report presents an overview of current technology and programs including some economic studies in low, intermediate, and high temperatre thermal energy storage for solar applications and an assessment of key problem areas. Previous studies of the economic role of storage for solar home heating and stand-alone electric plants are examined first and factors which affect the economics of storage are discussed. Next, the costs and storage capacities of representative sensible and latent heat storage materials are summarized. Various modes of operation are also presented for thermal storage by reversible chemical reactions, but this technology is at such an immature stage of development that its economic and technical potential are not clearly understood. Some new ideas in containers and heat exchangers are reviewed to illustrate possible innovative approaches to reducing storage costs. A more detailed examination is then made of reversible reaction storage, and gas-solid reactions are shown to have desirable attributes for solar energy storage. However, there are problems with heat transfer and heat exchanger for these systems that must be solved to make such systems more economically attractive. The DOE programs in thermal energy storage are reviewed in light of this review, and recommendations are made for future program directions which appear at this time to have the greatest potential impact on reducing technical and economic barriers to thermal storage utilization.

  1. Energy storage for the electricity grid : benefits and market potential assessment guide : a study for the DOE Energy Storage Systems Program.

    Energy Technology Data Exchange (ETDEWEB)

    Eyer, James M. (Distributed Utility Associates, Inc., Livermore, CA); Corey, Garth P. (KTech Corporation, Albuquerque, NM)

    2010-02-01

    This guide describes a high-level, technology-neutral framework for assessing potential benefits from and economic market potential for energy storage used for electric-utility-related applications. The overarching theme addressed is the concept of combining applications/benefits into attractive value propositions that include use of energy storage, possibly including distributed and/or modular systems. Other topics addressed include: high-level estimates of application-specific lifecycle benefit (10 years) in $/kW and maximum market potential (10 years) in MW. Combined, these criteria indicate the economic potential (in $Millions) for a given energy storage application/benefit. The benefits and value propositions characterized provide an important indication of storage system cost targets for system and subsystem developers, vendors, and prospective users. Maximum market potential estimates provide developers, vendors, and energy policymakers with an indication of the upper bound of the potential demand for storage. The combination of the value of an individual benefit (in $/kW) and the corresponding maximum market potential estimate (in MW) indicates the possible impact that storage could have on the U.S. economy. The intended audience for this document includes persons or organizations needing a framework for making first-cut or high-level estimates of benefits for a specific storage project and/or those seeking a high-level estimate of viable price points and/or maximum market potential for their products. Thus, the intended audience includes: electric utility planners, electricity end users, non-utility electric energy and electric services providers, electric utility regulators and policymakers, intermittent renewables advocates and developers, Smart Grid advocates and developers, storage technology and project developers, and energy storage advocates.

  2. Lower-Energy Energy Storage System (LEESS) Component Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Gonder, J.; Cosgrove, J.; Shi, Y.; Saxon, A.; Pesaran, A.

    2014-10-01

    Alternate hybrid electric vehicle (HEV) energy storage systems (ESS) such as lithium-ion capacitors (LICs) and electrochemical double-layer capacitor (EDLC) modules have the potential for improved life, superior cold temperature performance, and lower long-term cost projections relative to traditional battery storage systems. If such lower-energy ESS (LEESS) devices can also be shown to maintain high HEV fuel savings, future HEVs designed with these devices could have an increased value proposition relative to conventional vehicles. NREL's vehicle test platform is helping validate the in-vehicle performance capability of alternative LEESS devices and identify unforeseen issues. NREL created the Ford Fusion Hybrid test platform for in-vehicle evaluation of such alternative LEESS devices, bench testing of the initial LIC pack, integration and testing of the LIC pack in the test vehicle, and bench testing and installation of an EDLC module pack. EDLC pack testing will continue in FY15. The in-vehicle LIC testing results suggest technical viability of LEESS devices to support HEV operation. Several LIC configurations tested demonstrated equivalent fuel economy and acceleration performance as the production nickel-metal-hydride ESS configuration across all tests conducted. The lowest energy LIC scenario demonstrated equivalent performance over several tests, although slightly higher fuel consumption on the US06 cycle and slightly slower acceleration performance. More extensive vehicle-level calibration may be able to reduce or eliminate these performance differences. The overall results indicate that as long as critical attributes such as engine start under worst case conditions can be retained, considerable ESS downsizing may minimally impact HEV fuel savings.

  3. A Distributed Model Predictive Control approach for the integration of flexible loads, storage and renewables

    DEFF Research Database (Denmark)

    Ferrarini, Luca; Mantovani, Giancarlo; Costanzo, Giuseppe Tommaso

    2014-01-01

    This paper presents an innovative solution based on distributed model predictive controllers to integrate the control and management of energy consumption, energy storage, PV and wind generation at customer side. The overall goal is to enable an advanced prosumer to autoproduce part of the energy...... he needs with renewable sources and, at the same time, to optimally exploit the thermal and electrical storages, to trade off its comfort requirements with different pricing schemes (including real-time pricing), and apply optimal control techniques rather than sub-optimal heuristics....

  4. Optimal Placement of Energy Storage and Wind Power under Uncertainty

    Directory of Open Access Journals (Sweden)

    Pilar Meneses de Quevedo

    2016-07-01

    Full Text Available Due to the rapid growth in the amount of wind energy connected to distribution grids, they are exposed to higher network constraints, which poses additional challenges to system operation. Based on regulation, the system operator has the right to curtail wind energy in order to avoid any violation of system constraints. Energy storage systems (ESS are considered to be a viable solution to solve this problem. The aim of this paper is to provide the best locations of both ESS and wind power by optimizing distribution system costs taking into account network constraints and the uncertainty associated to the nature of wind, load and price. To do that, we use a mixed integer linear programming (MILP approach consisting of loss reduction, voltage improvement and minimization of generation costs. An alternative current (AC linear optimal power flow (OPF, which employs binary variables to define the location of the generation, is implemented. The proposed stochastic MILP approach has been applied to the IEEE 69-bus distribution network and the results show the performance of the model under different values of installed capacities of ESS and wind power.

  5. [Project to enhance bone bank tissue storage and distribution procedures].

    Science.gov (United States)

    Huang, Jui-Chen; Wu, Chiung-Lan; Chen, Chun-Chuan; Chen, Shu-Hua

    2011-10-01

    Organ and tissue transplantation are now commonly preformed procedures. Improper organ bank handling procedures may increase infection risks. Execution accuracy in terms of tissue storage and distribution at our bone bank was 80%. We thus proposed an execution improvement project to enhance procedures in order to fulfill the intent of donors and ensure recipient safety. This project was designed to raise nurse professionalism, and ensure patient safety through enhanced tissue storage and distribution procedures. Education programs developed for this project focus on teaching standard operating procedures for bone and ligament storage and distribution, bone bank facility maintenance, trouble shooting and solutions, and periodic inspection systems. Cognition of proper storage and distribution procedures rose from 81% to 100%; Execution accuracy also rose from 80% to 100%. The project successfully conveyed concepts essential to the correct execution of organ storage and distribution procedures and proper organ bank facility management. Achieving and maintaining procedural and management standards is crucial to continued organ donations and the recipient safety.

  6. Interconnection of Distributed Energy Resources

    Energy Technology Data Exchange (ETDEWEB)

    Reiter, Emerson [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-04-19

    This is a presentation on interconnection of distributed energy resources, including the relationships between different aspects of interconnection, best practices and lessons learned from different areas of the U.S., and an update on technical advances and standards for interconnection.

  7. 78 FR 9687 - Prineville Energy Storage, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

    Science.gov (United States)

    2013-02-11

    ... Energy Regulatory Commission Prineville Energy Storage, LLC; Notice of Preliminary Permit Application..., 2012, Prineville Energy Storage, LLC, filed an application for a preliminary permit, pursuant to...-hours. Applicant Contact: Mr. Matthew Shapiro, Chief Executive Officer, Prineville Energy Storage,...

  8. Energy Storage Systems Program Report for FY99

    Energy Technology Data Exchange (ETDEWEB)

    BOYES,JOHN D.

    2000-06-01

    Sandia National Laboratories, New Mexico, conducts the Energy Storage Systems Program, which is sponsored by the US Department of Energy's Office of Power Technologies. The goal of this program is to develop cost-effective electric energy storage systems for many high-value stationary applications in collaboration with academia and industry. Sandia National Laboratories is responsible for the engineering analyses, contracted development, and testing of energy storage components and systems. This report details the technical achievements realized during fiscal year 1999.

  9. Graphene and graphene-based materials for energy storage applications.

    Science.gov (United States)

    Zhu, Jixin; Yang, Dan; Yin, Zongyou; Yan, Qingyu; Zhang, Hua

    2014-09-10

    With the increased demand in energy resources, great efforts have been devoted to developing advanced energy storage and conversion systems. Graphene and graphene-based materials have attracted great attention owing to their unique properties of high mechanical flexibility, large surface area, chemical stability, superior electric and thermal conductivities that render them great choices as alternative electrode materials for electrochemical energy storage systems. This Review summarizes the recent progress in graphene and graphene-based materials for four energy storage systems, i.e., lithium-ion batteries, supercapacitors, lithium-sulfur batteries and lithium-air batteries.

  10. Design Considerations of a Solid State Thermal Energy Storage

    Science.gov (United States)

    Janbozorgi, Mohammad; Houssainy, Sammy; Thacker, Ariana; Ip, Peggy; Ismail, Walid; Kavehpour, Pirouz

    2016-11-01

    With the growing governmental restrictions on carbon emission, renewable energies are becoming more prevalent. A reliable use of a renewable source however requires a built-in storage to overcome the inherent intermittent nature of the available energy. Thermal design of a solid state energy storage has been investigated for optimal performance. The impact of flow regime, laminar vs. turbulent, on the design and sizing of the system is also studied. The implications of low thermal conductivity of the storage material are discussed and a design that maximizes the round trip efficiency is presented. This study was supported by Award No. EPC-14-027 Granted by California Energy Commission (CEC).

  11. Energy Storage Systems Program Report for FY98

    Energy Technology Data Exchange (ETDEWEB)

    Butler, P.C.

    1999-04-01

    Sandia National Laboratories, New Mexico, conducts the Energy Storage Systems Program, which is sponsored by the U.S. Department of Energy's Office of Power Technologies. The goal of this program is to collaborate with industry in developing cost-effective electric energy storage systems for many high-value stationary applications. Sandia National Laboratories is responsible for the engineering analyses, contracted development and testing of energy storage components and systems. This report details the technical achievements realized during fiscal year 1998.

  12. LIQUID AIR AS AN ENERGY STORAGE: A REVIEW

    Directory of Open Access Journals (Sweden)

    YVONNE LIM

    2016-04-01

    Full Text Available With the increasing demand for energy due to rapid industrialisation and the environmental concerns due to the usage of fossil fuels as the main energy source, there is a shift towards renewable energy. However, the intermittent nature of renewable energy requires energy produced during off-peak hours to be stored. This paper explores the use of liquefied air as an energy storage, the plausibility and the integration of liquefied air into existing framework, the role of liquefied air as an energy storage in addressing the Grand Challenges for Engineering as well as its employability in Malaysia.

  13. Using Cloud Storage for NMR Data Distribution

    Science.gov (United States)

    Soulsby, David

    2012-01-01

    An approach using Google Groups as method for distributing student-acquired NMR data has been implemented. We describe how to configure NMR spectrometer software so that data is uploaded to a laboratory section specific Google Group, thereby removing bottlenecks associated with printing and processing at the spectrometer workstation. Outside of…

  14. Using Cloud Storage for NMR Data Distribution

    Science.gov (United States)

    Soulsby, David

    2012-01-01

    An approach using Google Groups as method for distributing student-acquired NMR data has been implemented. We describe how to configure NMR spectrometer software so that data is uploaded to a laboratory section specific Google Group, thereby removing bottlenecks associated with printing and processing at the spectrometer workstation. Outside of…

  15. Ceph, a distributed storage system for scientific computing

    CERN Document Server

    CERN. Geneva

    2013-01-01

    Ceph is a distributed storage system designed to providing high performance and reliability at scales of up to thousands of storage nodes. The system is based on a distributed object storage layer call RADOS that provides durability, availability, efficient data distribution, and rich object semantics. This storage can be consumed directly via an object-based interface, or via file, block, or REST-based object services that are built on top of it. Clusters are composed of commodity components to provide a reliable storage service serving multiple use-cases. This seminar will cover the basic architecture of Ceph, with a focus on how each service can be consumed in a research and infrastructure environment. About the speaker Sage Weil, Founder and current CTO of Inktank Inc, is the creator of the Ceph project. He originally designed it as part of his PhD research in Storage Systems at the University of California, Santa Cruz. Since graduating, he has continued to refine the system with the goal of providi...

  16. Distribution System Pricing with Distributed Energy Resources

    Energy Technology Data Exchange (ETDEWEB)

    Hledik, Ryan [The Brattle Group, Cambridge, MA (United States); Lazar, Jim [The Regulatory Assistance Project, Montpelier, VT (United States); Schwartz, Lisa [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-08-16

    Technological changes in the electric utility industry bring tremendous opportunities and significant challenges. Customers are installing clean sources of on-site generation such as rooftop solar photovoltaic (PV) systems. At the same time, smart appliances and control systems that can communicate with the grid are entering the retail market. Among the opportunities these changes create are a cleaner and more diverse power system, the ability to improve system reliability and system resilience, and the potential for lower total costs. Challenges include integrating these new resources in a way that maintains system reliability, provides an equitable sharing of system costs, and avoids unbalanced impacts on different groups of customers, including those who install distributed energy resources (DERs) and low-income households who may be the least able to afford the transition.

  17. Searchable Data Vault: Encrypted Queries in Secure Distributed Cloud Storage

    Directory of Open Access Journals (Sweden)

    Geong Sen Poh

    2017-05-01

    Full Text Available Cloud storage services allow users to efficiently outsource their documents anytime and anywhere. Such convenience, however, leads to privacy concerns. While storage providers may not read users’ documents, attackers may possibly gain access by exploiting vulnerabilities in the storage system. Documents may also be leaked by curious administrators. A simple solution is for the user to encrypt all documents before submitting them. This method, however, makes it impossible to efficiently search for documents as they are all encrypted. To resolve this problem, we propose a multi-server searchable symmetric encryption (SSE scheme and construct a system called the searchable data vault (SDV. A unique feature of the scheme is that it allows an encrypted document to be divided into blocks and distributed to different storage servers so that no single storage provider has a complete document. By incorporating the scheme, the SDV protects the privacy of documents while allowing for efficient private queries. It utilizes a web interface and a controller that manages user credentials, query indexes and submission of encrypted documents to cloud storage services. It is also the first system that enables a user to simultaneously outsource and privately query documents from a few cloud storage services. Our preliminary performance evaluation shows that this feature introduces acceptable computation overheads when compared to submitting documents directly to a cloud storage service.

  18. Self-powered energy fiber: energy conversion in the sheath and storage in the core.

    Science.gov (United States)

    Yang, Zhibin; Deng, Jue; Sun, Hao; Ren, Jing; Pan, Shaowu; Peng, Huisheng

    2014-11-05

    A high-performance, self-powered, elastic energy fiber is developed that consists of an energy conversion sheath and an energy storage core. The coaxial structure and the aligned nanostructures at the electrode interface enable a high total energy-conversion and energy-storage performance that is maintained under bending and after stretching.

  19. Modeling Pumped Thermal Energy Storage with Waste Heat Harvesting

    Science.gov (United States)

    Abarr, Miles L. Lindsey

    This work introduces a new concept for a utility scale combined energy storage and generation system. The proposed design utilizes a pumped thermal energy storage (PTES) system, which also utilizes waste heat leaving a natural gas peaker plant. This system creates a low cost utility-scale energy storage system by leveraging this dual-functionality. This dissertation first presents a review of previous work in PTES as well as the details of the proposed integrated bottoming and energy storage system. A time-domain system model was developed in Mathworks R2016a Simscape and Simulink software to analyze this system. Validation of both the fluid state model and the thermal energy storage model are provided. The experimental results showed the average error in cumulative fluid energy between simulation and measurement was +/- 0.3% per hour. Comparison to a Finite Element Analysis (FEA) model showed energy of a recently proposed Pumped Thermal Energy Storage and Bottoming System (Bot-PTES) that uses ammonia as the working fluid. This analysis focused on the effects of hot thermal storage utilization, system pressure, and evaporator/condenser size on the system performance. This work presents the estimated performance for a proposed baseline Bot-PTES. Results of this analysis showed that all selected parameters had significant effects on efficiency, with the evaporator/condenser size having the largest effect over the selected ranges. Results for the baseline case showed stand-alone energy storage efficiencies between 51 and 66% for varying power levels and charge states, and a stand-alone bottoming efficiency of 24%. The resulting efficiencies for this case were low compared to competing technologies; however, the dual-functionality of the Bot-PTES enables it to have higher capacity factor, leading to 91-197/MWh levelized cost of energy compared to 262-284/MWh for batteries and $172-254/MWh for Compressed Air Energy Storage.

  20. Proceedings of the DOE chemical energy storage and hydrogen energy systems contracts review

    Energy Technology Data Exchange (ETDEWEB)

    1980-02-01

    Sessions were held on electrolysis-based hydrogen storage systems, hydrogen production, hydrogen storage systems, hydrogen storage materials, end-use applications and system studies, chemical heat pump/chemical energy storage systems, systems studies and assessment, thermochemical hydrogen production cycles, advanced production concepts, and containment materials. (LHK)

  1. Preliminary survey and evaluation of nonaquifer thermal energy storage concepts for seasonal storage

    Energy Technology Data Exchange (ETDEWEB)

    Blahnik, D.E.

    1980-11-01

    Thermal energy storage enables the capture and retention of heat energy (or cold) during one time period for use during another. Seasonal thermal energy storage (STES) involves a period of months between the input and recovery of energy. The purpose of this study was to make a preliminary investigation and evaluation of potential nonaquifer STES systems. Current literature was surveyed to determine the state of the art of thermal energy storage (TES) systems such as hot water pond storage, hot rock storage, cool ice storage, and other more sophisticated concepts which might have potential for future STES programs. The main energy sources for TES principally waste heat, and the main uses of the stored thermal energy, i.e., heating, cooling, and steam generation are described. This report reviews the development of sensible, latent, and thermochemical TES technologies, presents a preliminary evaluation of the TES methods most applicable to seasonal storage uses, outlines preliminary conclusions drawn from the review of current TES literature, and recommends further research based on these conclusions. A bibliography of the nonaquifer STES literature review, and examples of 53 different TES concepts drawn from the literature are provided. (LCL)

  2. Energy storage specification requirements for hybrid-electric vehicle

    Science.gov (United States)

    Burke, A. F.

    1993-09-01

    A study has been made of energy storage unit requirements for hybrid-electric vehicles. The drivelines for these vehicles included both primary energy storage units and/or pulse power units. The primary energy storage units were sized to provide 'primary energy' ranges up to 60 km. The total power capability of the drivelines were such that the vehicles had 0 to 100 km/h acceleration times of 10 to 12 s. The power density requirements for primary energy storage devices to be used in hybrid vehicles are much higher than that for devices to be used in electric vehicles. The energy density and power density requirements for pulse-power devices for hybrid vehicles, are not much different than those in an electric vehicle. The cycle life requirements for primary energy-storage units for hybrid vehicles are about double that for electric vehicles, because of the reduced size of the storage units in the hybrid vehicles. The cycle life for pulse-power devices for hybrid vehicles is about the same as for electric vehicles having battery load leveling. Because of the need for additional components in the hybrid driveline, the cost of the energy storage units in hybrid vehicles should be much less (at least a factor of two) than those in electric vehicles. There are no presently available energy storage units that meet all the specifications for hybrid vehicle applications, but ultracapacitors and bipolar lead-acid batteries are under development that have the potential for meeting them. If flywheel systems having a mechanical system energy density of 40 to 50 W(center dot)h/kg and an electrical system power density of 2 to 3 kw/kg can be developed, they would have the potential of meeting specifications for primary storage and pulse power units.

  3. Slow Dynamics Model of Compressed Air Energy Storage and Battery Storage Technologies for Automatic Generation Control

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, Venkat; Das, Trishna

    2016-05-01

    Increasing variable generation penetration and the consequent increase in short-term variability makes energy storage technologies look attractive, especially in the ancillary market for providing frequency regulation services. This paper presents slow dynamics model for compressed air energy storage and battery storage technologies that can be used in automatic generation control studies to assess the system frequency response and quantify the benefits from storage technologies in providing regulation service. The paper also represents the slow dynamics model of the power system integrated with storage technologies in a complete state space form. The storage technologies have been integrated to the IEEE 24 bus system with single area, and a comparative study of various solution strategies including transmission enhancement and combustion turbine have been performed in terms of generation cycling and frequency response performance metrics.

  4. Economic Analysis of using Above Ground Gas Storage Devices for Compressed Air Energy Storage System

    Institute of Scientific and Technical Information of China (English)

    LIU Jinchao; ZHANG Xinjing; XU Yujie; CHEN Zongyan; CHEN Haisheng; TAN Chunqing

    2014-01-01

    Above ground gas storage devices for compressed air energy storage (CAES) have three types:air storage tanks,gas cylinders,and gas storage pipelines.A cost model of these gas storage devices is established on the basis of whole life cycle cost (LCC) analysis.The optimum parameters of the three types are determined by calculating the theoretical metallic raw material consumption of these three devices and considering the difficulties in manufacture and the influence of gas storage device number.The LCCs of the three types are comprehensively analyzed and compared.The result reveal that the cost of the gas storage pipeline type is lower than that of the other two types.This study may serve as a reference for designing large-scale CAES systems.

  5. Investigation of Energy Storage Systems, Its Advantage and Requirement in Various Locations in Australia

    Directory of Open Access Journals (Sweden)

    Mohammad Taufiqul Arif

    2013-01-01

    Full Text Available Storage minimizes the intermittent nature of renewable sources. Solar and wind are the two fostered source of renewable energy. However, the availability of useful solar radiation and wind speed varies with geographical locations, and also the duration of this energy sources varies with seasonal variation. With the available vast open land and geographical position, Australia has great potential for both solar and wind energies. However, both these sources require energy buffering to support load demand to ensure required power quality. Electricity demand is increasing gradually, and also Australia has target to achieve 20% electricity from renewable sources by 2020. For effective utilization of solar and wind energy potential location of these sources needs to be identified, and effective size of storage needs to be estimated for best utilization according to the load demand. Therefore this paper investigated wind speed and solar radiation data of 210 locations in Australia, identified the potential locations, and estimated required storage in various potential locations to support residential load demand. Advantages of storage were analyzed in terms of loading on distribution transformer and storage support during energy fluctuation from renewable energy. Further analysis showed that storage greatly reduces greenhouse gas emission and reduces overall cost of energy by maximizing the use of solar and wind energies.

  6. Overview of a flywheel stack energy storage system

    Science.gov (United States)

    Kirk, James A.; Anand, Davinder K.

    1988-01-01

    The concept of storing electrical energy in rotating flywheels provides an attractive substitute to batteries. To realize these advantages the critical technologies of rotor design, composite materials, magnetic suspension, and high efficiency motor/generators are reviewed in this paper. The magnetically suspended flywheel energy storage system, currently under development at the University of Maryland, consisting of a family of interference assembled rings, is presented as an integrated solution for energy storage.

  7. Energy: Systems for Control, Maintenance, and Storage. A Bibliography.

    Science.gov (United States)

    Thomas, Gerald, Comp.; McKane, Irving, Comp.

    This publication is a bibliography of available periodical literature on specific aspects of energy and today's technology. The Applied Science and Technology Indexes were searched for articles that related to these specific areas: (1) Energy control systems; (2) Maintenance of Energy Systems; and (3) Energy storage. The articles and papers…

  8. A Wireless Power Sharing Control Strategy for Hybrid Energy Storage Systems in DC Microgrids

    DEFF Research Database (Denmark)

    Yang, Jie; Jin, Xinmin; Wu, Xuezhi

    2017-01-01

    In order to compensate multiple time scales power fluctuation resulted from distributed energy resources and loads, hybrid energy storage systems are employed as the buffer unit in DC microgrid. In this paper, a wireless hierarchical control strategy is proposed to realize power sharing between...

  9. Seneca Compressed Air Energy Storage (CAES) Project

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-11-30

    This document provides specifications for the process air compressor for a compressed air storage project, requests a budgetary quote, and provides supporting information, including compressor data, site specific data, water analysis, and Seneca CAES value drivers.

  10. Energy Storage System with Voltage Equalization Strategy for Wind Energy Conversion

    Directory of Open Access Journals (Sweden)

    Cheng-Tao Tsai

    2012-07-01

    Full Text Available In this paper, an energy storage system with voltage equalization strategy for wind energy conversion is presented. The proposed energy storage system provides a voltage equalization strategy for series-connected lead-acid batteries to increase their total storage capacity and lifecycle. In order to draw the maximum power from the wind energy, a perturbation-and-observation method and digital signal processor (DSP are incorporated to implement maximum power point tracking (MPPT algorithm and power regulating scheme. In the proposed energy storage system, all power switches have zero-voltage-switching (ZVS feature at turn-on transition. Therefore, the conversion efficiency can be increased. Finally, a prototype energy storage system for wind energy conversion is built and implemented. Experimental results have verified the performance and feasibility of the proposed energy storage system for wind energy conversion.

  11. Energy efficient distributed computing systems

    CERN Document Server

    Lee, Young-Choon

    2012-01-01

    The energy consumption issue in distributed computing systems raises various monetary, environmental and system performance concerns. Electricity consumption in the US doubled from 2000 to 2005.  From a financial and environmental standpoint, reducing the consumption of electricity is important, yet these reforms must not lead to performance degradation of the computing systems.  These contradicting constraints create a suite of complex problems that need to be resolved in order to lead to 'greener' distributed computing systems.  This book brings together a group of outsta

  12. Multilayer PV-storage Microgrids Algorithm for the Dispatch of Distributed Network

    Directory of Open Access Journals (Sweden)

    Yang Ping

    2016-01-01

    Full Text Available In recent years, due to the support of our country, PV-storage microgrid develops rapidly. However, the flexible network operation modes of PV-storage microgrid change flexibly and the operating characteristics with a large amout of sources is highly complicated. Based on the existing microgrid coordinate control methods, this paper proposes multilayer PV-storage microgrid algorithm for fitting dispatch of distributed network, which achieves maximum output of renewable energy when meeting the scheduling requirements of network, by building PV-storage microgrid type dynamic simulation system in a variety of conditions in PSCAD. Simulation results show that the heuristic algorithm proposed can achieve microgrid stable operation and satisfy the demands of the dispatch in distributed network.

  13. A Communication-less Distributed Control Architecture for Islanded Microgrids with Renewable Generation and Storage

    DEFF Research Database (Denmark)

    Aldana, Nelson Leonardo Diaz; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2017-01-01

    For reliable operation of an islanded microgrid, at least one of its distributed resources should assume the responsibility of forming the off-grid power system. This responsibility is usually assumed by energy storage systems based on their capability of compensating the unbalance between...

  14. Battery Energy Storage Technology for power systems-An overview

    DEFF Research Database (Denmark)

    Chandrashekhara, Divya K; Østergaard, Jacob

    2009-01-01

    the present status of battery energy storage technology and methods of assessing their economic viability and impact on power system operation. Further, a discussion on the role of battery storage systems of electric hybrid vehicles in power system storage technologies had been made. Finally, the paper...... suggests a likely future outlook for the battery technologies and the electric hybrid vehicles in the context of power system applications....

  15. Paper‐Based Electrodes for Flexible Energy Storage Devices

    Science.gov (United States)

    Yao, Bin; Zhang, Jing; Kou, Tianyi; Song, Yu; Liu, Tianyu

    2017-01-01

    Paper‐based materials are emerging as a new category of advanced electrodes for flexible energy storage devices, including supercapacitors, Li‐ion batteries, Li‐S batteries, Li‐oxygen batteries. This review summarizes recent advances in the synthesis of paper‐based electrodes, including paper‐supported electrodes and paper‐like electrodes. Their structural features, electrochemical performances and implementation as electrodes for flexible energy storage devices including supercapacitors and batteries are highlighted and compared. Finally, we also discuss the challenges and opportunity of paper‐based electrodes and energy storage devices. PMID:28725532

  16. Battery energy storage systems life cycle costs case studies

    Energy Technology Data Exchange (ETDEWEB)

    Swaminathan, S.; Miller, N.F.; Sen, R.K. [SENTECH, Inc., Bethesda, MD (United States)

    1998-08-01

    This report presents a comparison of life cycle costs between battery energy storage systems and alternative mature technologies that could serve the same utility-scale applications. Two of the battery energy storage systems presented in this report are located on the supply side, providing spinning reserve and system stability benefits. These systems are compared with the alternative technologies of oil-fired combustion turbines and diesel generators. The other two battery energy storage systems are located on the demand side for use in power quality applications. These are compared with available uninterruptible power supply technologies.

  17. Electrical Energy Storage for the Grid: A Battery of Choices

    Science.gov (United States)

    Dunn, Bruce; Kamath, Haresh; Tarascon, Jean-Marie

    2011-11-01

    The increasing interest in energy storage for the grid can be attributed to multiple factors, including the capital costs of managing peak demands, the investments needed for grid reliability, and the integration of renewable energy sources. Although existing energy storage is dominated by pumped hydroelectric, there is the recognition that battery systems can offer a number of high-value opportunities, provided that lower costs can be obtained. The battery systems reviewed here include sodium-sulfur batteries that are commercially available for grid applications, redox-flow batteries that offer low cost, and lithium-ion batteries whose development for commercial electronics and electric vehicles is being applied to grid storage.

  18. Multifunctional Carbon Nanostructures for Advanced Energy Storage Applications

    Directory of Open Access Journals (Sweden)

    Yiran Wang

    2015-05-01

    Full Text Available Carbon nanostructures—including graphene, fullerenes, etc.—have found applications in a number of areas synergistically with a number of other materials. These multifunctional carbon nanostructures have recently attracted tremendous interest for energy storage applications due to their large aspect ratios, specific surface areas, and electrical conductivity. This succinct review aims to report on the recent advances in energy storage applications involving these multifunctional carbon nanostructures. The advanced design and testing of multifunctional carbon nanostructures for energy storage applications—specifically, electrochemical capacitors, lithium ion batteries, and fuel cells—are emphasized with comprehensive examples.

  19. Efficiency improvement for wind energy pumped storage systems

    DEFF Research Database (Denmark)

    Forcos, A.; Marinescu, C.; Teodorescu, Remus

    2011-01-01

    Integrating wind energy into the grid may raise stability problems. Solutions for avoiding these situations are studied and energy storage methods are suitable for balancing the energy between the wind turbine and grid. In this paper, an autonomous wind turbine pumped storage system is presented....... The focus of this paper is to improve the efficiency of this system, which is small at low power levels. The driving motorpump group of the storage system is the key point presented in this paper for efficiency improving. Two control methods, experimentally implemented for induction machine are presented...

  20. Hybrid energy storage: the merging of battery and supercapacitor chemistries.

    Science.gov (United States)

    Dubal, D P; Ayyad, O; Ruiz, V; Gómez-Romero, P

    2015-04-07

    The hybrid approach allows for a reinforcing combination of properties of dissimilar components in synergic combinations. From hybrid materials to hybrid devices the approach offers opportunities to tackle much needed improvements in the performance of energy storage devices. This paper reviews the different approaches and scales of hybrids, materials, electrodes and devices striving to advance along the diagonal of Ragone plots, providing enhanced energy and power densities by combining battery and supercapacitor materials and storage mechanisms. Furthermore, some theoretical aspects are considered regarding the possible hybrid combinations and tactics for the fabrication of optimized final devices. All of it aiming at enhancing the electrochemical performance of energy storage systems.

  1. Electrical energy storage for the grid: a battery of choices.

    Science.gov (United States)

    Dunn, Bruce; Kamath, Haresh; Tarascon, Jean-Marie

    2011-11-18

    The increasing interest in energy storage for the grid can be attributed to multiple factors, including the capital costs of managing peak demands, the investments needed for grid reliability, and the integration of renewable energy sources. Although existing energy storage is dominated by pumped hydroelectric, there is the recognition that battery systems can offer a number of high-value opportunities, provided that lower costs can be obtained. The battery systems reviewed here include sodium-sulfur batteries that are commercially available for grid applications, redox-flow batteries that offer low cost, and lithium-ion batteries whose development for commercial electronics and electric vehicles is being applied to grid storage.

  2. Towards greener and more sustainable batteries for electrical energy storage.

    Science.gov (United States)

    Larcher, D; Tarascon, J-M

    2015-01-01

    Ever-growing energy needs and depleting fossil-fuel resources demand the pursuit of sustainable energy alternatives, including both renewable energy sources and sustainable storage technologies. It is therefore essential to incorporate material abundance, eco-efficient synthetic processes and life-cycle analysis into the design of new electrochemical storage systems. At present, a few existing technologies address these issues, but in each case, fundamental and technological hurdles remain to be overcome. Here we provide an overview of the current state of energy storage from a sustainability perspective. We introduce the notion of sustainability through discussion of the energy and environmental costs of state-of-the-art lithium-ion batteries, considering elemental abundance, toxicity, synthetic methods and scalability. With the same themes in mind, we also highlight current and future electrochemical storage systems beyond lithium-ion batteries. The complexity and importance of recycling battery materials is also discussed.

  3. Towards greener and more sustainable batteries for electrical energy storage

    Science.gov (United States)

    Larcher, D.; Tarascon, J.-M.

    2015-01-01

    Ever-growing energy needs and depleting fossil-fuel resources demand the pursuit of sustainable energy alternatives, including both renewable energy sources and sustainable storage technologies. It is therefore essential to incorporate material abundance, eco-efficient synthetic processes and life-cycle analysis into the design of new electrochemical storage systems. At present, a few existing technologies address these issues, but in each case, fundamental and technological hurdles remain to be overcome. Here we provide an overview of the current state of energy storage from a sustainability perspective. We introduce the notion of sustainability through discussion of the energy and environmental costs of state-of-the-art lithium-ion batteries, considering elemental abundance, toxicity, synthetic methods and scalability. With the same themes in mind, we also highlight current and future electrochemical storage systems beyond lithium-ion batteries. The complexity and importance of recycling battery materials is also discussed.

  4. NASA Langley Research Center's distributed mass storage system

    Science.gov (United States)

    Pao, Juliet Z.; Humes, D. Creig

    1993-01-01

    There is a trend in institutions with high performance computing and data management requirements to explore mass storage systems with peripherals directly attached to a high speed network. The Distributed Mass Storage System (DMSS) Project at NASA LaRC is building such a system and expects to put it into production use by the end of 1993. This paper presents the design of the DMSS, some experiences in its development and use, and a performance analysis of its capabilities. The special features of this system are: (1) workstation class file servers running UniTree software; (2) third party I/O; (3) HIPPI network; (4) HIPPI/IPI3 disk array systems; (5) Storage Technology Corporation (STK) ACS 4400 automatic cartridge system; (6) CRAY Research Incorporated (CRI) CRAY Y-MP and CRAY-2 clients; (7) file server redundancy provision; and (8) a transition mechanism from the existent mass storage system to the DMSS.

  5. Symmetric Electrodes for Electrochemical Energy-Storage Devices.

    Science.gov (United States)

    Zhang, Lei; Dou, Shi Xue; Liu, Hua Kun; Huang, Yunhui; Hu, Xianluo

    2016-12-01

    Increasing environmental problems and energy challenges have so far attracted urgent demand for developing green and efficient energy-storage systems. Among various energy-storage technologies, sodium-ion batteries (SIBs), electrochemical capacitors (ECs) and especially the already commercialized lithium-ion batteries (LIBs) are playing very important roles in the portable electronic devices or the next-generation electric vehicles. Therefore, the research for finding new electrode materials with reduced cost, improved safety, and high-energy density in these energy storage systems has been an important way to satisfy the ever-growing demands. Symmetric electrodes have recently become a research focus because they employ the same active materials as both the cathode and anode in the same energy-storage system, leading to the reduced manufacturing cost and simplified fabrication process. Most importantly, this feature also endows the symmetric energy-storage system with improved safety, longer lifetime, and ability of charging in both directions. In this Progress Report, we provide the comprehensive summary and comment on different symmetric electrodes and focus on the research about the applications of symmetric electrodes in different energy-storage systems, such as the above mentioned SIBs, ECs and LIBs. Further considerations on the possibility of mass production have also been presented.

  6. Energy conservation in electric distribution

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chong-Jin

    1994-12-31

    This paper discusses the potential for energy and power savings that exist in electric power delivery systems. These savings translate into significant financial and environmental benefits for electricity producers and consumers as well as for society in general. AlliedSignal`s knowledge and perspectives on this topic are the result of discussions with hundreds of utility executives, government officials and other industry experts over the past decade in conjunction with marketing our Amorphous Metal technology for electric distribution transformers. Amorphous metal is a technology developed by AlliedSignal that significantly reduces the energy lost in electric distribution transformers at an incremental cost of just a few cents per kilo-Watt-hour. The purpose of this paper is to discuss: Amorphous Metal Alloy Technology; Energy Savings Opportunity; The Industrial Barriers and Remedies; Worldwide Demand; and A Low Risk Strategy. I wish this presentation will help KEPCO achieve their stated aims of ensuring sound development of the national economy and enhancement of public life through the economic and stable supply of electric power. AlliedSignal Korea Ltd. in conjunction with AlliedSignal Amorphous Metals in the U.S. are here to work with KEPCO, transformer manufacturers, industry, and government agencies to achieve greater efficiency in power distribution.

  7. Modeling of battery energy storage in the National Energy Modeling System

    Energy Technology Data Exchange (ETDEWEB)

    Swaminathan, S.; Flynn, W.T.; Sen, R.K. [Sentech, Inc., Bethesda, MD (United States)

    1997-12-01

    The National Energy Modeling System (NEMS) developed by the U.S. Department of Energy`s Energy Information Administration is a well-recognized model that is used to project the potential impact of new electric generation technologies. The NEMS model does not presently have the capability to model energy storage on the national grid. The scope of this study was to assess the feasibility of, and make recommendations for, the modeling of battery energy storage systems in the Electricity Market of the NEMS. Incorporating storage within the NEMS will allow the national benefits of storage technologies to be evaluated.

  8. Modeling of battery energy storage in the National Energy Modeling System

    Energy Technology Data Exchange (ETDEWEB)

    Swaminathan, S.; Flynn, W.T.; Sen, R.K. [Sentech, Inc., Bethesda, MD (United States)

    1997-12-01

    The National Energy Modeling System (NEMS) developed by the U.S. Department of Energy`s Energy Information Administration is a well-recognized model that is used to project the potential impact of new electric generation technologies. The NEMS model does not presently have the capability to model energy storage on the national grid. The scope of this study was to assess the feasibility of, and make recommendations for, the modeling of battery energy storage systems in the Electricity Market of the NEMS. Incorporating storage within the NEMS will allow the national benefits of storage technologies to be evaluated.

  9. Bulk energy storage increases United States electricity system emissions.

    Science.gov (United States)

    Hittinger, Eric S; Azevedo, Inês M L

    2015-03-03

    Bulk energy storage is generally considered an important contributor for the transition toward a more flexible and sustainable electricity system. Although economically valuable, storage is not fundamentally a "green" technology, leading to reductions in emissions. We model the economic and emissions effects of bulk energy storage providing an energy arbitrage service. We calculate the profits under two scenarios (perfect and imperfect information about future electricity prices), and estimate the effect of bulk storage on net emissions of CO2, SO2, and NOx for 20 eGRID subregions in the United States. We find that net system CO2 emissions resulting from storage operation are nontrivial when compared to the emissions from electricity generation, ranging from 104 to 407 kg/MWh of delivered energy depending on location, storage operation mode, and assumptions regarding carbon intensity. Net NOx emissions range from -0.16 (i.e., producing net savings) to 0.49 kg/MWh, and are generally small when compared to average generation-related emissions. Net SO2 emissions from storage operation range from -0.01 to 1.7 kg/MWh, depending on location and storage operation mode.

  10. Operational Benefits of Meeting California's Energy Storage Targets

    Energy Technology Data Exchange (ETDEWEB)

    Eichman, Josh [National Renewable Energy Lab. (NREL), Golden, CO (United States); Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Helman, Udi [Helman Analytics, San Francisco, CA (United States)

    2015-12-18

    providing regulation reserve, as the added storage could provide about 75% of the regulation up requirement for all of California, which would likely greatly reduce regulation prices and potential revenue. The addition of storage in California decreases renewable curtailment, particularly in the 40% RPS case. Following previous analysis, storage has a mixed impact on emissions, generally reducing emissions, but also creating additional incentives for increased emissions from out-of-state coal generations. Overall, storage shows significant system cost savings, but analysis also points to additional challenges associated with full valuation of energy storage, including capturing the operational benefits calculated here, but also recovering additional benefits associated avoided generation, transmission, and distribution capacity, and avoided losses.

  11. Recent Progress on Integrated Energy Conversion and Storage Systems.

    Science.gov (United States)

    Luo, Bin; Ye, Delai; Wang, Lianzhou

    2017-09-01

    Over the last few decades, there has been increasing interest in the design and construction of integrated energy conversion and storage systems (IECSSs) that can simultaneously capture and store various forms of energies from nature. A large number of IECSSs have been developed with different combination of energy conversion technologies such as solar cells, mechanical generators and thermoelectric generators and energy storage devices such as rechargeable batteries and supercapacitors. This review summarizes the recent advancements to date of IECSSs based on different energy sources including solar, mechanical, thermal as well as multiple types of energies, with a special focus on the system configuration and working mechanism. With the rapid development of new energy conversion and storage technologies, innovative high performance IECSSs are of high expectation to be realised for diverse practical applications in the near future.

  12. Investigation into the potential of energy storage to tackle intermittency in renewable energy generation

    OpenAIRE

    Barbour, Edward

    2013-01-01

    Renewable Energy is by nature intermittent and matching the supply of energy to specific time dependent demand poses huge challenges. Energy storage is a useful tool in handling this temporal disparity, although except for regions very suitable for pumped hydroelectric storage schemes, it suffers from being technically difficult to implement and costly as a result. This study investigates the potential benefits offered by various scales of energy storage to different types of r...

  13. Potential and Evolution of Compressed Air Energy Storage: Energy and Exergy Analyses

    OpenAIRE

    Young-Min Kim; Jang-Hee Lee; Seok-Joon Kim; Daniel Favrat

    2012-01-01

    Energy storage systems are increasingly gaining importance with regard to their role in achieving load levelling, especially for matching intermittent sources of renewable energy with customer demand, as well as for storing excess nuclear or thermal power during the daily cycle. Compressed air energy storage (CAES), with its high reliability, economic feasibility, and low environmental impact, is a promising method for large-scale energy storage. Although there are only two large-scale CAES p...

  14. Buffer thermal energy storage for a solar Brayton engine

    Science.gov (United States)

    Strumpf, H. J.; Barr, K. P.

    1981-01-01

    A study has been completed on the application of latent-heat buffer thermal energy storage to a point-focusing solar receiver equipped with an air Brayton engine. To aid in the study, a computer program was written for complete transient/stead-state Brayton cycle performance. The results indicated that thermal storage can afford a significant decrease in the number of engine shutdowns as compared to operating without thermal storage. However, the number of shutdowns does not continuously decrease as the storage material weight increases. In fact, there appears to be an optimum weight for minimizing the number of shutdowns.

  15. Enhanced Reliability of Photovoltaic Systems with Energy Storage and Controls

    Energy Technology Data Exchange (ETDEWEB)

    Manz, D.; Schelenz, O.; Chandra, R.; Bose, S.; de Rooij, M.; Bebic, J.

    2008-02-01

    This report summarizes efforts to reconfigure loads during outages to allow individual customers the opportunity to enhance the reliability of their electric service through the management of their loads, photovoltaics, and energy storage devices.

  16. Technology Base Research Project for electrochemical energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, K. (ed.)

    1991-06-01

    This report is an executive summary of major project goals and descriptions for electrochemical energy storage. Exploratory research, applied science research, air systems research, milestones, and management activities are a few of the topics discussed. (JL)

  17. Inspecting Underground Storage Tanks - 2005 Energy Policy Act

    Science.gov (United States)

    these grant guidelines implement the inspection provisions in Sections 9005(c)(1) and 9005(c)(2) of the Solid Waste Disposal Act, enacted by the Underground Storage Tank Compliance Act, part of the Energy Policy Act of 2005.

  18. Solar Power Augmented Electrolysis Module for Energy Storage Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Regenerative fuel cell systems often include a dedicated electrolysis module with solar photovoltaic (PV) panels packaged as a subsystem of the larger energy storage...

  19. Public Record About Underground Storage Tanks - 2005 Energy Policy Act

    Science.gov (United States)

    These grant guidelines implement the public record provision in Section 9002(d) of the Solid Waste Disposal Act, enacted by the Underground Storage Tank Compliance Act, part of the Energy Policy Act of 2005.

  20. Wide Temperature Range Hybrid Energy Storage Device Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal concerns the fabrication of a hybrid battery capacitor (HBC) using Eltron's knowledge gained in battery and capacitor research. Energy storage systems...

  1. Crosstalk compensation in analysis of energy storage devices

    Science.gov (United States)

    Christophersen, Jon P; Morrison, John L; Morrison, William H; Motloch, Chester G; Rose, David M

    2014-06-24

    Estimating impedance of energy storage devices includes generating input signals at various frequencies with a frequency step factor therebetween. An excitation time record (ETR) is generated to include a summation of the input signals and a deviation matrix of coefficients is generated relative to the excitation time record to determine crosstalk between the input signals. An energy storage device is stimulated with the ETR and simultaneously a response time record (RTR) is captured that is indicative of a response of the energy storage device to the ETR. The deviation matrix is applied to the RTR to determine an in-phase component and a quadrature component of an impedance of the energy storage device at each of the different frequencies with the crosstalk between the input signals substantially removed. This approach enables rapid impedance spectra measurements that can be completed within one period of the lowest frequency or less.

  2. Local Thermal Insulating Materials For Thermal Energy Storage ...

    African Journals Online (AJOL)

    Local Thermal Insulating Materials For Thermal Energy Storage. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL · RESOURCES ... In this paper the thermal properties of selected potential local materials ...

  3. Recent advances in energy storage materials and devices

    CERN Document Server

    Lu, Li

    2017-01-01

    This book compiles nine comprehensive contributions from the principle of Li-ion batteries, cathode and anode electrode materials to future energy storage systems such as solid electrolyte for all-solid-state batteries and high capacity redox flow battery.

  4. Mutlifunctional Fibers for Energy Storage in Advanced EVA Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall objective of the Phase II effort is to demonstrate prototype multifunctional EVA system power patches that integrate energy storage into advanced space...

  5. European resource assessment for geothermal energy and CO2 storage

    NARCIS (Netherlands)

    Wees, J.D. van; Neele, F.

    2013-01-01

    Geothermal Energy and CO2 Capture and Storage (CCS) are both considered major contributors to the global energy transition. Their success critically depends on subsurface resource quality, which in turn depends on specific subsurface parameters. For CCS and Geothermal Energy these in some respect ov

  6. European resource assessment for geothermal energy and CO2 storage

    NARCIS (Netherlands)

    Wees, J.D. van; Neele, F.

    2013-01-01

    Geothermal Energy and CO2 Capture and Storage (CCS) are both considered major contributors to the global energy transition. Their success critically depends on subsurface resource quality, which in turn depends on specific subsurface parameters. For CCS and Geothermal Energy these in some respect

  7. Bidding strategy for an energy storage facility

    DEFF Research Database (Denmark)

    Nasrolahpour, Ehsan; Zareipour, Hamidreza; Rosehart, William D.;

    2016-01-01

    to maximize its profit, while the market operator aims at maximizing the social welfare. In this case, the storage facility adapts its strategic behavior to take advantage of market conditions. To model the imperfectly competitive market, a bi-level optimization model is implemented to present...

  8. Magnesium Hydride for Load Levelling Energy Storage

    DEFF Research Database (Denmark)

    Vigeholm, B.

    Some of the magnesium properties essential to the applicability of the reaction Mg+H2⇆MgH2 as a hydrogen storage system have been investigated. Three magnesium powders with particle size smaller than 50 μm average diameter were cycled, over 31, 71 and 151 cycles respectively, at 675K (400°C...

  9. Value of Energy Storage for Grid Applications (Report Summary) (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, P.; Jorgenson, J.; Hummon, M.; Jenkin, T.; Palchak, D.; Kirby, B.; Ma, O.; O' Malley, M.

    2013-06-01

    This analysis evaluates several operational benefits of electricity storage, including load-leveling, spinning contingency reserves, and regulation reserves. Storage devices were simulated in a utility system in the western United States, and the operational costs of generation was compared to the same system without the added storage. This operational value of storage was estimated for devices of various sizes, providing different services, and with several sensitivities to fuel price and other factors. Overall, the results followed previous analyses that demonstrate relatively low value for load-leveling but greater value for provision of reserve services. The value was estimated by taking the difference in operational costs between cases with and without energy storage and represents the operational cost savings from deploying storage by a traditional vertically integrated utility. The analysis also estimated the potential revenues derived from a merchant storage plant in a restructured market, based on marginal system prices. Due to suppression of on-/off-peak price differentials and incomplete capture of system benefits (such as the cost of power plant starts), the revenue obtained by storage in a market setting appears to be substantially less than the net benefit provided to the system. This demonstrates some of the additional challenges for storage deployed in restructured energy markets.

  10. The Value of Energy Storage for Grid Applications

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hummon, Marissa [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jenkin, Thomas [National Renewable Energy Lab. (NREL), Golden, CO (United States); Palchak, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kirby, Brendan [Kirby Consultant; Ma, Ookie [U.S. Department of Energy, Washington, DC (United States); O' Malley, Mark [Univ. College of Dublin (Ireland)

    2013-05-01

    This analysis evaluates several operational benefits of electricity storage, including load-leveling, spinning contingency reserves, and regulation reserves. Storage devices were simulated in a utility system in the western United States, and the operational costs of generation was compared to the same system without the added storage. This operational value of storage was estimated for devices of various sizes, providing different services, and with several sensitivities to fuel price and other factors. Overall, the results followed previous analyses that demonstrate relatively low value for load-leveling but greater value for provision of reserve services. The value was estimated by taking the difference in operational costs between cases with and without energy storage and represents the operational cost savings from deploying storage by a traditional vertically integrated utility. The analysis also estimated the potential revenues derived from a merchant storage plant in a restructured market, based on marginal system prices. Due to suppression of on-/off-peak price differentials and incomplete capture of system benefits (such as the cost of power plant starts), the revenue obtained by storage in a market setting appears to be substantially less than the net benefit provided to the system. This demonstrates some of the additional challenges for storage deployed in restructured energy markets.

  11. Coordinated control of wind power and energy storage

    OpenAIRE

    Zhao, Haoran; Wu, Qiuwei; Rasmussen, Claus Nygaard; Xu, Honghua

    2014-01-01

    Nowadays, wind power has become one of the fastest growing sources of electricity in the world. Due to the inherent variability and uncertainty, wind power integration into the grid brings challenges for power systems, particularly when the wind power penetration level is high. The challenges exist in many aspects, such as reliability, power quality and stability. With the rapid development of energy storage technology, the application of Energy Storage System (ESS) is considered as an effect...

  12. Chemical energy storage: Part of a systemic solution

    Science.gov (United States)

    Schlögl, Robert

    2017-07-01

    This paper is a primer into concepts and opportunities of chemical energy storage. Starting from the quest for decarbonisation we reveal the possibilities of chemical energy storage. We briefly discuss the critical role of catalysis as enabling technology. We concentrate on options of large-scale production of chemicals from CO2 and green hydrogen. We discuss one potential application of fueling future combustion engines that could run with minimal regulated emissions without exhaust purifications and legal tricks.

  13. Electrochemical supercapacitors for energy storage and delivery fundamentals and applications

    CERN Document Server

    Yu, Aiping

    2013-01-01

    Although recognized as an important component of all energy storage and conversion technologies, electrochemical supercapacitators (ES) still face development challenges in order to reach their full potential. A thorough examination of development in the technology during the past decade, Electrochemical Supercapacitors for Energy Storage and Delivery: Fundamentals and Applications provides a comprehensive introduction to the ES from technical and practical aspects and crystallization of the technology, detailing the basics of ES as well as its components and characterization techniques. The b

  14. Geothermal energy and heat storage in aquifers

    NARCIS (Netherlands)

    Ewalts, W.P.G.; Geluk, M.C.; Heederik, J.P.; Huurdeman, A.J.M.; Mourik, G.J. van; Postma, A.D.; Snijders, A.L.; Walter, F.; Willemsen, A.

    1988-01-01

    After the first energy crisis in 1973 various research programmes to do with energy conservation and diversification of energy resources were set up in the Netherlands. A number of these were directed to the rest of the subsoil for the following purposes: - the extraction of geothermal energy from g

  15. Geothermal energy and heat storage in aquifers

    NARCIS (Netherlands)

    Ewalts, W.P.G.; Geluk, M.C.; Heederik, J.P.; Huurdeman, A.J.M.; Mourik, G.J. van; Postma, A.D.; Snijders, A.L.; Walter, F.; Willemsen, A.

    1988-01-01

    After the first energy crisis in 1973 various research programmes to do with energy conservation and diversification of energy resources were set up in the Netherlands. A number of these were directed to the rest of the subsoil for the following purposes: - the extraction of geothermal energy from

  16. Design Considerations for High Energy Electron -- Positron Storage Rings

    Science.gov (United States)

    Richter, B.

    1966-11-01

    High energy electron-positron storage rings give a way of making a new attack on the most important problems of elementary particle physics. All of us who have worked in the storage ring field designing, building, or using storage rings know this. The importance of that part of storage ring work concerning tests of quantum electrodynamics and mu meson physics is also generally appreciated by the larger physics community. However, I do not think that most of the physicists working tin the elementary particle physics field realize the importance of the contribution that storage ring experiments can make to our understanding of the strongly interacting particles. I would therefore like to spend the next few minutes discussing the sort of things that one can do with storage rings in the strongly interacting particle field.

  17. Parametric analysis of a packed bed thermal energy storage system

    Science.gov (United States)

    Ortega-Fernández, Iñigo; Loroño, Iñaki; Faik, Abdessamad; Uriz, Irantzu; Rodríguez-Aseguinolaza, Javier; D'Aguanno, Bruno

    2017-06-01

    Even if the packed bed thermal energy storage concept has been introduced as a promising technology in the concentrated solar power field in the last years, its full deployment in commercial plants presents a clear improvement potential. In order to overcome the under-development of this storage technology, this work attempts to show the great capabilities of packed bed heat storage units after a successful design and operational parametric optimization procedure. The obtained results show that a correct design of this type of facilities together with a successful operation method, allow to increase significantly the storage capacity reaching an overall efficiency higher than 80 %. The design guideline obtained as a result of this work could open new objectives and applications for the packed bed storage technology as it represents a cost-effective and highly performing storage alternative.

  18. Design and management of energy-efficient hybrid electrical energy storage systems

    CERN Document Server

    Kim, Younghyun

    2014-01-01

    This book covers system-level design optimization and implementation of hybrid energy storage systems. The author introduces various techniques to improve the performance of hybrid energy storage systems, in the context of design optimization and automation. Various energy storage techniques are discussed, each with its own advantages and drawbacks, offering viable, hybrid approaches to building a high performance, low cost energy storage system. Novel design optimization techniques and energy-efficient operation schemes are introduced. The author also describes the technical details of an act

  19. Battery technologies for large-scale stationary energy storage.

    Science.gov (United States)

    Soloveichik, Grigorii L

    2011-01-01

    In recent years, with the deployment of renewable energy sources, advances in electrified transportation, and development in smart grids, the markets for large-scale stationary energy storage have grown rapidly. Electrochemical energy storage methods are strong candidate solutions due to their high energy density, flexibility, and scalability. This review provides an overview of mature and emerging technologies for secondary and redox flow batteries. New developments in the chemistry of secondary and flow batteries as well as regenerative fuel cells are also considered. Advantages and disadvantages of current and prospective electrochemical energy storage options are discussed. The most promising technologies in the short term are high-temperature sodium batteries with β″-alumina electrolyte, lithium-ion batteries, and flow batteries. Regenerative fuel cells and lithium metal batteries with high energy density require further research to become practical.

  20. Improved accounting of emissions from utility energy storage system operation.

    Science.gov (United States)

    Denholm, Paul; Holloway, Tracey

    2005-12-01

    Several proposed utility-scale energy storage systems in the U.S. will use the spare output capacity of existing electric power systems to create the equivalent of new load-following plants that can rapidly respond to fluctuations in electricity demand and increase the flexibility of baseload generators. New energy storage systems using additional generation from existing plants can directly compete with new traditional sources of load-following and peaking electricity, yet this application of energy storage is not required to meet many of the Clean Air Act standards required of new electricity generators (e.g., coal- or gas-fired power plants). This study evaluates the total emissions that will likely result from the operation of a new energy storage facility when coupled with an average existing U.S. coal-fired power plant and estimates that the emission rates of SO2 and NOx will be considerably higher than the rate of a new plant meeting Clean Air Act standards, even accounting for the efficiency benefits of energy storage. This study suggests that improved emissions "accounting" might be necessary to provide accurate environmental comparisons between energy storage and more traditional sources of electricity generation.