network energy storage: Topics by WorldWideScience.org

Sample records for network energy storage

Silicon-embedded copper nanostructure network for high energy storage

Science.gov (United States)

Yu, Tianyue

2016-03-15

Provided herein are nanostructure networks having high energy storage, electrochemically active electrode materials including nanostructure networks having high energy storage, as well as electrodes and batteries including the nanostructure networks having high energy storage. According to various implementations, the nanostructure networks have high energy density as well as long cycle life. In some implementations, the nanostructure networks include a conductive network embedded with electrochemically active material. In some implementations, silicon is used as the electrochemically active material. The conductive network may be a metal network such as a copper nanostructure network. Methods of manufacturing the nanostructure networks and electrodes are provided. In some implementations, metal nanostructures can be synthesized in a solution that contains silicon powder to make a composite network structure that contains both. The metal nanostructure growth can nucleate in solution and on silicon nanostructure surfaces.
Silicon-embedded copper nanostructure network for high energy storage

Energy Technology Data Exchange (ETDEWEB)

Yu, Tianyue

2018-01-23

Provided herein are nanostructure networks having high energy storage, electrochemically active electrode materials including nanostructure networks having high energy storage, as well as electrodes and batteries including the nanostructure networks having high energy storage. According to various implementations, the nanostructure networks have high energy density as well as long cycle life. In some implementations, the nanostructure networks include a conductive network embedded with electrochemically active material. In some implementations, silicon is used as the electrochemically active material. The conductive network may be a metal network such as a copper nanostructure network. Methods of manufacturing the nanostructure networks and electrodes are provided. In some implementations, metal nanostructures can be synthesized in a solution that contains silicon powder to make a composite network structure that contains both. The metal nanostructure growth can nucleate in solution and on silicon nanostructure surfaces.
Flowable Conducting Particle Networks in Redox-Active Electrolytes for Grid Energy Storage

Energy Technology Data Exchange (ETDEWEB)

Hatzell, K. B.; Boota, M.; Kumbur, E. C.; Gogotsi, Y.

2015-01-01

This study reports a new hybrid approach toward achieving high volumetric energy and power densities in an electrochemical flow capacitor for grid energy storage. The electrochemical flow capacitor suffers from high self-discharge and low energy density because charge storage is limited to the available surface area (electric double layer charge storage). Here, we examine two carbon materials as conducting particles in a flow battery electrolyte containing the VO2+/VO2+ redox couple. Highly porous activated carbon spheres (CSs) and multi-walled carbon nanotubes (MWCNTs) are investigated as conducting particle networks that facilitate both faradaic and electric double layer charge storage. Charge storage contributions (electric double layer and faradaic) are distinguished for flow-electrodes composed of MWCNTs and activated CSs. A MWCNT flow-electrode based in a redox-active electrolyte containing the VO2+/VO2+ redox couple demonstrates 18% less self-discharge, 10 X more energy density, and 20 X greater power densities (at 20 mV s-1) than one based on a non-redox active electrolyte. Furthermore, a MWCNT redox-active flow electrode demonstrates 80% capacitance retention, and >95% coulombic efficiency over 100 cycles, indicating the feasibility of utilizing conducting networks with redox chemistries for grid energy storage.
Modeling of District Heating Networks for the Purpose of Operational Optimization with Thermal Energy Storage

Science.gov (United States)

Leśko, Michał; Bujalski, Wojciech

2017-12-01

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

International Nuclear Information System (INIS)

Bace, M.; Knapp, V.

1981-01-01

Energy storage is of great importance for the exploitation of new energy sources as well as for the better utilisation of conventional ones. Several proposals in recent years have suggested that superconducting magnets could be used as energy storage in large electricity networks. It is a purpose of this note to point out that the requirements which have to be met by energy storage in a large electricity network place serious limitation on the possible use of superconducting energy storage. (author)
Fuzzy-driven energy storage system for mitigating voltage unbalance factor on distribution network with photovoltaic system

Science.gov (United States)

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

2017-04-01

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

Science.gov (United States)

Liu, Lu; Tong, Yibin; Zhao, Zhigang; Zhang, Xuefen

2018-03-01

Large-scale access of distributed residential photovoltaic (PV) in rural areas has solved the voltage problem to a certain extent. However, due to the intermittency of PV and the particularity of rural residents’ power load, the problem of low voltage in the evening peak remains to be resolved. This paper proposes to solve the problem by accessing residential energy storage. Firstly, the influence of access location and capacity of energy storage on voltage distribution in rural distribution network is analyzed. Secondly, the relation between the storage capacity and load capacity is deduced for four typical load and energy storage cases when the voltage deviation meets the demand. Finally, the optimal storage position and capacity are obtained by using PSO and power flow simulation.
Efficient Supercapacitor Energy Storage Using Conjugated Microporous Polymer Networks Synthesized from Buchwald-Hartwig Coupling.

Science.gov (United States)

Liao, Yaozu; Wang, Haige; Zhu, Meifang; Thomas, Arne

2018-03-01

Supercapacitors have received increasing interest as energy storage devices due to their rapid charge-discharge rates, high power densities, and high durability. In this work, novel conjugated microporous polymer (CMP) networks are presented for supercapacitor energy storage, namely 3D polyaminoanthraquinone (PAQ) networks synthesized via Buchwald-Hartwig coupling between 2,6-diaminoanthraquinone and aryl bromides. PAQs exhibit surface areas up to 600 m 2 g -1 , good dispersibility in polar solvents, and can be processed to flexible electrodes. The PAQs exhibit a three-electrode specific capacitance of 576 F g -1 in 0.5 m H 2 SO 4 at a current of 1 A g -1 retaining 80-85% capacitances and nearly 100% Coulombic efficiencies (95-98%) upon 6000 cycles at a current density of 2 A g -1 . Asymmetric two-electrode supercapacitors assembled by PAQs show a capacitance of 168 F g -1 of total electrode materials, an energy density of 60 Wh kg -1 at a power density of 1300 W kg -1 , and a wide working potential window (0-1.6 V). The asymmetric supercapacitors show Coulombic efficiencies up to 97% and can retain 95.5% of initial capacitance undergo 2000 cycles. This work thus presents novel promising CMP networks for charge energy storage. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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
Solar heat storages in district heating networks

Energy Technology Data Exchange (ETDEWEB)

Ellehauge, K. (Ellehauge og Kildemoes, AArhus (DK)); Engberg Pedersen, T. (COWI A/S, Kgs. Lyngby (DK))

2007-07-15

This report gives information on the work carried out and the results obtained in Denmark on storages for large solar heating plants in district heating networks. Especially in Denmark the share of district heating has increased to a large percentage. In 1981 around 33% of all dwellings in DK were connected to a district heating network, while the percentage in 2006 was about 60% (in total 1.5 mio. dwellings). In the report storage types for short term storage and long term storages are described. Short term storages are done as steel tanks and is well established technology widely used in district heating networks. Long term storages are experimental and used in connection with solar heating. A number of solar heating plants have been established with either short term or long term storages showing economy competitive with normal energy sources. Since, in the majority of the Danish district heating networks the heat is produced in co-generation plants, i.e. plants producing both electricity and heat for the network, special attention has been put on the use of solar energy in combination with co-generation. Part of this report describes that in the liberalized electricity market central solar heating plants can also be advantageous in combination with co-generation plants. (au)
Metal sulfide electrodes and energy storage devices thereof

Science.gov (United States)

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.
Electric energy storage - Overview of technologies

International Nuclear Information System (INIS)

Boye, Henri

2013-01-01

Energy storage is a challenging and costly process, as electricity can only be stored by conversion into other forms of energy (e.g. potential, thermal, chemical or magnetic energy). The grids must be precisely balanced in real time and it must be made sure that the cost of electricity is the lowest possible. Storage of electricity has many advantages, in centralized mass storages used for the management of the transmission network, or in decentralized storages of smaller dimensions. This article presents an overview of the storage technologies: mechanical storage in hydroelectric and pumped storage power stations, compressed air energy storage (CAES), flywheels accumulating kinetic energy, electrochemical batteries with various technologies, traditional lead acid batteries, lithium ion, sodium sulfur (NaS) and others, including vehicle to grid, sensible heat thermal storage, superconducting magnetic energy storage (SMES), super-capacitors, conversion into hydrogen... The different technologies are compared in terms of cost and level of maturity. The development of intermittent renewable energies will result in a growing need for mechanisms to regulate energy flow and innovative energy storage solutions seem well positioned to develop. (author)
Design and analysis of electrical energy storage demonstration projects on UK distribution networks

International Nuclear Information System (INIS)

Lyons, P.F.; Wade, N.S.; Jiang, T.; Taylor, P.C.; Hashiesh, F.; Michel, M.; Miller, D.

2015-01-01

Highlights: • Results of an EES system demonstration project carried out in the UK. • Approaches to the design of trials for EES and observation on their application. • A formalised methodology for analysis of smart grids trials. • Validated models of energy storage. • Capability of EES to connect larger quantities of heat pumps and PV is evaluated. - Abstract: The UK government’s CO 2 emissions targets will require electrification of much of the country’s infrastructure with low carbon technologies such as photovoltaic panels, electric vehicles and heat pumps. The large scale proliferation of these technologies will necessitate major changes to the planning and operation of distribution networks. Distribution network operators are trialling electrical energy storage (EES) across their networks to increase their understanding of the contribution that it can make to enable the expected paradigm shift in generation and consumption of electricity. In order to evaluate a range of applications for EES, including voltage control and power flow management, installations have taken place at various distribution network locations and voltage levels. This article reports on trial design approaches and their application to a UK trial of an EES system to ensure broad applicability of the results. Results from these trials of an EES system, low carbon technologies and trial distribution networks are used to develop validated power system models. These models are used to evaluate, using a formalised methodology, the impact that EES could have on the design and operation of future distribution networks
Optimal scheduling for distribution network with redox flow battery storage

International Nuclear Information System (INIS)

Hosseina, Majid; Bathaee, Seyed Mohammad Taghi

2016-01-01

Highlights: • A novel method for optimal scheduling of storages in radial network is presented. • Peak shaving and load leveling are the main objectives. • Vanadium redox flow battery is considered as the energy storage unit. • Real data is used for simulation. - Abstract: There are many advantages to utilize storages in electric power system. Peak shaving, load leveling, load frequency control, integration of renewable, energy trading and spinning reserve are the most important of them. Batteries, especially redox flow batteries, are one of the appropriate storages for utilization in distribution network. This paper presents a novel, heuristic and practical method for optimal scheduling in distribution network with flow battery storage. This heuristic method is more suitable for scheduling and operation of distribution networks which require installation of storages. Peak shaving and load leveling is considered as the main objective in this paper. Several indices are presented in this paper for determine the place of storages and also scheduling for optimal use of energy in them. Simulations of this paper are based on real information of distribution network substation that located in Semnan, Iran.
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
Superconducting magnetic energy storage

International Nuclear Information System (INIS)

Rogers, J.D.; Boenig, H.J.

1978-01-01

Superconducting inductors provide a compact and efficient means of storing electrical energy without an intermediate conversion process. Energy storage inductors are under development for diurnal load leveling and transmission line stabilization in electric utility systems and for driving magnetic confinement and plasma heating coils in fusion energy systems. Fluctuating electric power demands force the electric utility industry to have more installed generating capacity than the average load requires. Energy storage can increase the utilization of base-load fossil and nuclear power plants for electric utilities. Superconducting magnetic energy storage (SMES) systems, which will store and deliver electrical energy for load leveling, peak shaving, and the stabilization of electric utility networks are being developed. In the fusion area, inductive energy transfer and storage is also being developed by LASL. Both 1-ms fast-discharge theta-pinch and 1-to-2-s slow tokamak energy transfer systems have been demonstrated. The major components and the method of operation of an SMES unit are described, and potential applications of different size SMES systems in electric power grids are presented. Results are given for a 1-GWh reference design load-leveling unit, for a 30-MJ coil proposed stabilization unit, and for tests with a small-scale, 100-kJ magnetic energy storage system. The results of the fusion energy storage and transfer tests are also presented. The common technology base for the systems is discussed
Optical storage networking

Science.gov (United States)

Mohr, Ulrich

2001-11-01

For efficient business continuance and backup of mission- critical data an inter-site storage network is required. Where traditional telecommunications costs are prohibitive for all but the largest organizations, there is an opportunity for regional carries to deliver an innovative storage service. This session reveals how a combination of optical networking and protocol-aware SAN gateways can provide an extended storage networking platform with the lowest cost of ownership and the highest possible degree of reliability, security and availability. Companies of every size, with mainframe and open-systems environments, can afford to use this integrated service. Three mayor applications are explained; channel extension, Network Attached Storage (NAS), Storage Area Networks (SAN) and how optical networks address the specific requirements. One advantage of DWDM is the ability for protocols such as ESCON, Fibre Channel, ATM and Gigabit Ethernet, to be transported natively and simultaneously across a single fiber pair, and the ability to multiplex many individual fiber pairs over a single pair, thereby reducing fiber cost and recovering fiber pairs already in use. An optical storage network enables a new class of service providers, Storage Service Providers (SSP) aiming to deliver value to the enterprise by managing storage, backup, replication and restoration as an outsourced service.
Optimal placement, sizing, and daily charge/discharge of battery energy storage in low voltage distribution network with high photovoltaic penetration

DEFF Research Database (Denmark)

Jannesar, Mohammad Rasol; Sedighi, Alireza; Savaghebi, Mehdi

2018-01-01

when photovoltaic penetration is increased in low voltage distribution network. Local battery energy storage system can mitigate these disadvantages and as a result, improve the system operation. For this purpose, battery energy storage system is charged when production of photovoltaic is more than...... consumers’ demands and discharged when consumers’ demands are increased. Since the price of battery energy storage system is high, economic, environmental, and technical objectives should be considered together for its placement and sizing. In this paper, optimal placement, sizing, and daily (24 h) charge......Proper installation of rooftop photovoltaic generation in distribution networks can improve voltage profile, reduce energy losses, and enhance the reliability. But, on the other hand, some problems regarding harmonic distortion, voltage magnitude, reverse power flow, and energy losses can arise...
Energy storage

International Nuclear Information System (INIS)

Anon.

1992-01-01

This chapter discusses the role that energy storage may have on the energy future of the US. The topics discussed in the chapter include historical aspects of energy storage, thermal energy storage including sensible heat storage, latent heat storage, thermochemical heat storage, and seasonal heat storage, electricity storage including batteries, pumped hydroelectric storage, compressed air energy storage, and superconducting magnetic energy storage, and production and combustion of hydrogen as an energy storage option
Ten questions to Jean Dhers on the storage of electric energy

International Nuclear Information System (INIS)

2006-01-01

The authors proposes a comprehensive set of technical and economical data and information on electricity storage: the reasons to store energy (autonomous, stationary and network applications), the different types and advantages of energy storages with reversible power, the means to massively store electricity to exploit in on the network (description, uses and comparison of pumping energy transfer station, energy storage under the form of compressed air), the inertial storage (storage of kinetic energy accumulated in a flywheel, and its applications), the importance of storage with electrochemical batteries (reversible storage, evolution of batteries in ground transports, main economic sectors for batteries), fuel cells, the role of energy storage by power capacitors, the perspectives of super capacitors in a near future (comparison of their performance with those of batteries, possible applications), the use of electromagnetic storage of electricity (description, advantages, drawbacks and applications of superconducting magnet energy storage or SMES), and how the research on electric power storage is organised

Research on Battery Energy Storage System Based on User Side

Science.gov (United States)

Wang, Qian; Zhang, Yichi; Yun, Zejian; Wang, Xuguang; Zhang, Dong; Bian, Di

2018-01-01

This paper introduces the effect of user side energy storage on the user side and the network side, a battery energy storage system for the user side is designed. The main circuit topology of the battery energy storage system based on the user side is given, the structure is mainly composed of two parts: DC-DC two-way half bridge converter and DC-AC two-way converter, a control strategy combining battery charging and discharging characteristics is proposed to decouple the grid side and the energy storage side, and the block diagram of the charging and discharging control of the energy storage system is given. The simulation results show that the battery energy storage system of the user side can not only realize reactive power compensation of low-voltage distribution network, but also improve the power quality of the users.
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.
Regenesys utility scale energy storage. Overview report of combined energy storage and renewable generation

International Nuclear Information System (INIS)

2004-01-01

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
Grid integration of decentralized generation facilities by means of battery storages in the distribution network using the pilot project 'INESS' (Intelligent network energy storage system) as an example; Netzintegration von dezentralen Erzeugungsanlagen durch Batteriespeicher im Verteilnetz am Beispiel des Pilotprojektes 'INESS' (Intelligentes Netz Energie Speicher-System)

Energy Technology Data Exchange (ETDEWEB)

Stoelzle, Franz; Bader, Daniel [Netzgesellschaft Ostwuerttemberg GmbH, Ellwangen (Germany); Backes, Juergen [EnBW OstwuerttembergDonauRies AG, Ellwangen (Germany)

2012-07-01

Fundamentally, storage facilities may replace conventional grid building measures. The storage facility thus adopts the function as an additional load if a large decentralized supply is into the network is performed. The storage facility acts as a generating plant at high reference load when the storage facility is unloaded. In order to replace a network expansion optimally, the storage facilities are at least optimized decentralized such as the corresponding power generating plants. The required capacity of the storage facility depends on the case of application. When used as an alternative to the network expansion, relatively high capacities with 6 kWh per kW of the installed generation capacity are required. Due to the rarely occuring maximum input performance only a low energy turnover is achieved. Under current framework conditions and realities of the market storage facilities exclusively for this application currently can not operated economically. Combined use of storage facilities by customers, trade and standards of the grid operator could allow an economical operation with modified framework conditions and corresponding decline in prices of energy storage systems.
Joint Planning Of Energy Storage and Transmission Considering Wind-Storage Combined System and Demand Side Response

Science.gov (United States)

Huang, Y.; Liu, B. Z.; Wang, K. Y.; Ai, X.

2017-12-01

In response to the new requirements of the operation mode of wind-storage combined system and demand side response for transmission network planning, this paper presents a joint planning of energy storage and transmission considering wind-storage combined system and demand side response. Firstly, the charge-discharge strategy of energy storage system equipped at the outlet of wind farm and demand side response strategy are analysed to achieve the best comprehensive benefits through the coordination of the two. Secondly, in the general transmission network planning model with wind power, both energy storage cost and demand side response cost are added to the objective function. Not only energy storage operation constraints and but also demand side response constraints are introduced into the constraint condition. Based on the classical formulation of TEP, a new formulation is developed considering the simultaneous addition of the charge-discharge strategy of energy storage system equipped at the outlet of the wind farm and demand side response strategy, which belongs to a typical mixed integer linear programming model that can be solved by mature optimization software. The case study based on the Garver-6 bus system shows that the validity of the proposed model is verified by comparison with general transmission network planning model. Furthermore, the results demonstrate that the joint planning model can gain more economic benefits through setting up different cases.
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.
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…
Energy Storage Management in Grid Connected Solar Photovoltaic System

OpenAIRE

Vidhya M.E

2015-01-01

The penetration of renewable sources in the power system network in the power system has been increasing in the recent years. One of the solutions being proposed to improve the reliability and performance of these systems is to integrate energy storage device into the power system network. This paper discusses the modeling of photo voltaic and status of the storage device such as lead acid battery for better energy management in the system. The energy management for the grid conne...
Energy storage

International Nuclear Information System (INIS)

2012-01-01

After having outlined the importance of energy storage in the present context, this document outlines that it is an answer to economic, environmental and technological issues. It proposes a brief overview of the various techniques of energy storage: under the form of chemical energy (hydrocarbons, biomass, hydrogen production), thermal energy (sensitive or latent heat storage), mechanical energy (potential energy by hydraulic or compressed air storage, kinetic energy with flywheels), electrochemical energy (in batteries), electric energy (super-capacitors, superconductor magnetic energy storage). Perspectives are briefly evoked
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...
Impact Analysis of Demand Response Intensity and Energy Storage Size on Operation of Networked Microgrids

Directory of Open Access Journals (Sweden)

Akhtar Hussain

2017-06-01

Full Text Available Integration of demand response (DR programs and battery energy storage system (BESS in microgrids are beneficial for both microgrid owners and consumers. The intensity of DR programs and BESS size can alter the operation of microgrids. Meanwhile, the optimal size for BESS units is linked with the uncertainties associated with renewable energy sources and load variations. Similarly, the participation of enrolled customers in DR programs is also uncertain and, among various other factors, uncertainty in market prices is a major cause. Therefore, in this paper, the impact of DR program intensity and BESS size on the operation of networked microgrids is analyzed while considering the prevailing uncertainties. The uncertainties associated with forecast load values, output of renewable generators, and market price are realized via the robust optimization method. Robust optimization has the capability to provide immunity against the worst-case scenario, provided the uncertainties lie within the specified bounds. The worst-case scenario of the prevailing uncertainties is considered for evaluating the feasibility of the proposed method. The two representative categories of DR programs, i.e., price-based and incentive-based DR programs are considered. The impact of change in DR intensity and BESS size on operation cost of the microgrid network, external power trading, internal power transfer, load profile of the network, and state-of-charge (SOC of battery energy storage system (BESS units is analyzed. Simulation results are analyzed to determine the integration of favorable DR program and/or BESS units for different microgrid networks with diverse objectives.
Grid Converters for Stationary Battery Energy Storage Systems

DEFF Research Database (Denmark)

Trintis, Ionut

The integration of renewable energy sources in the power system, with high percentage, is a well known challenge nowadays. Power sources like wind and solar are highly volatile, with uctuations on various time scales. One long term solution is to build a continentwide or worldwide supergrid....... Another solution is to use distributed energy storage units, and create virtual power plants. Stationary energy storage is a complementary solution, which can postpone the network expansion and can be optimized for dierent kind of grid services. As an energy storage solution with timing for few seconds...... multilevel converter structure with integrated energy storage is introduced. This converter structure is suitable to interface low and medium voltage energy storage units to medium and high voltage grids. It can also interconnect a DC and AC grid with bidirectional power ow, were both can be backed...
Integrated topology optimisation of multi-energy networks

NARCIS (Netherlands)

Mazairac, L.A.J.; Salenbien, R.; Vanhoudt, D.; Desmedt, J.; Vries, de B.

2015-01-01

Multi-carrier hybrid energy distribution net- works provide flexibility in case of network malfunctions, energy shortages and price fluctuations through energy conversion and storage. Therefore hybrid networks can cope with large-scale integration of distributed and intermittent renewable energy
Energy storage

Science.gov (United States)

Kaier, U.

1981-04-01

Developments in the area of energy storage are characterized, with respect to theory and laboratory, by an emergence of novel concepts and technologies for storing electric energy and heat. However, there are no new commercial devices on the market. New storage batteries as basis for a wider introduction of electric cars, and latent heat storage devices, as an aid for solar technology applications, with satisfactory performance standards are not yet commercially available. Devices for the intermediate storage of electric energy for solar electric-energy systems, and for satisfying peak-load current demands in the case of public utility companies are considered. In spite of many promising novel developments, there is yet no practical alternative to the lead-acid storage battery. Attention is given to central heat storage for systems transporting heat energy, small-scale heat storage installations, and large-scale technical energy-storage systems.
Evaluating the benefits of an electrical energy storage system in a future smart grid

International Nuclear Information System (INIS)

Wade, N.S.; Taylor, P.C.; Lang, P.D.; Jones, P.R.

2010-01-01

Interest in electrical energy storage systems is increasing as the opportunities for their application become more compelling in an industry with a back-drop of ageing assets, increasing distributed generation and a desire to transform networks into Smart Grids. A field trial of an energy storage system designed and built by ABB is taking place on a section of 11 kV distribution network operated by EDF Energy Networks in Great Britain. This paper reports on the findings from simulation software developed at Durham University that evaluates the benefits brought by operating an energy storage system in response to multiple events on multiple networks. The tool manages the allocation of a finite energy resource to achieve the most beneficial shared operation across two adjacent areas of distribution network. Simulations account for the key energy storage system parameters of capacity and power rating. Results for events requiring voltage control and power flow management show how the choice of operating strategy influences the benefits achieved. The wider implications of these results are discussed to provide an assessment of the role of electrical energy storage systems in future Smart Grids.
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.
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.
Single stage grid converters for battery energy storage

DEFF Research Database (Denmark)

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

2010-01-01

Integration of renewable energy systems in the power system network such as wind and solar is still a challenge in our days. Energy storage systems (ESS) can overcome the disadvantage of volatile generation of the renewable energy sources. This paper presents power converters for battery energy...
Economics of Energy Storage. An analysis of the administrative consequences of electricity storage

International Nuclear Information System (INIS)

Wals, A.F.; Hendriks, R.H.

2004-03-01

This report discusses the administrative aspects connected to the introduction of electricity storage in the energy system. First, the macro-economic aspects of utilizing storage facilities are discussed, and the possible benefits of storage in the electricity system are summarized. Next, the discussion focuses on the administrative aspects. In particular, the regulation system of the Dutch electricity market is reviewed, paying particular attention to the market design in connection with Distribution Network Operators. A number of relevant aspects are discussed, such as the incentives for the Operators to optimize network performance, as well as the means available to the Operators to stimulate third parties to do so. Finally, the perspectives for storage operators to enter directly on the different power markets are treated. Generally, one can conclude that the administrative aspects for storage facilities leave room for improvement
Optimal sizing of energy storage system for microgrids

Indian Academy of Sciences (India)

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 ...

Energy Storage Management for Grid Operation Purposes

OpenAIRE

Ricardo Santos; Ricardo André; Ricardo Bessa; Clara Gouveia; António Araújo; Filipe Guerra; José Damásio; Guillermo Bravo; Jean Sumaili

2016-01-01

The Horizon 2020 Storage ENabled SustaInable energy for BuiLdings and communitiEs (SENSIBLE) project is currently looking at the integration of small-scale storage technologies in buildings and distribution networks. In the demonstration site of the SENSIBLE project, EDP has already installed an experimental storage system supplying a university campus in MV. It was mainly designed to increase service quality to the university by providing backup power in the event of MV grid failure, but it ...
Energy storage systems: a strategic road-book

International Nuclear Information System (INIS)

2011-01-01

Dealing with the development and deployment of thermal and electric energy storage systems, this report first identifies four main challenges: to take environmental challenges into account during all the storage system life (design, production, use, end of life), to integrate the issue of economic valorization of the device into its design phase, to promote the development of standards, to make an institutional and legal framework emerge. It defines the geographical scope and the time horizon for the development of these systems. It evokes research and development programs in the United States, Japan, China, Germany and the European Union. These programs concern: mobile electric storage systems, electric storage systems in support of energy networks and renewable energies, heat storage systems. The authors outline that business models are now favourable to the deployment of storage systems. They discuss some key technological and economical parameters. They propose some prospective visions by 2050 with different possible orientations for this sector. They also identify and discuss the possible technological and socio-economical obstacles, research priorities, and stress the importance of implementing experimental platforms and research demonstrators
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.
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.
Evaluation of an earth heat storage system in a solar energy greenhouse

Energy Technology Data Exchange (ETDEWEB)

Zhang, Q.; Langrell, J.; Boris, R. [Manitoba Univ., Winnipeg, MB (Canada). Dept. of Biosystems Engineering

2010-07-01

Greenhouses store solar energy in the walls and floors during the daytime and release the stored energy back to the greenhouse at night. In this study, an earth heat storage system was constructed and tested in a solar energy greenhouse in order to enhance energy storage. The system consisted of a network of perforated pipes buried in the soil at depths from 0.3 to 1 m. The warm air near the greenhouse ceiling was drawn to the buried pipes. Soil and air temperatures were recorded at various locations by a network of thermocouples. The energy balance was analyzed in order to evaluate the effectiveness of the earth heat storage system. The temperature profiles in the soil were used to determine the summer recharge and winter energy depletion behaviour of the system.
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
Special file on the storage of energies

International Nuclear Information System (INIS)

Signoret, Stephane; Kim, Caroline; Bohlinger, Philippe; Petitot, Pauline; Mary, Olivier; Guilhem, Jean

2017-01-01

After brief presentations of current research and industrial activities, a first article comments the new impetus of storage technologies and projects due to regulatory and legal evolutions associated with the French law on energy transition. Self-consumption and flexibility systems in distribution networks are practical factors of this evolution. Benefits provided by energy storage are notably outlined. The next articles present several examples: a decentralised heat storage in Brest, a flywheel plant by Levisys. An article then discusses the technological and commercial aspects of the battle in this sector for the French majors (EDF, Engie, Total). An article comments the emergence and development of a range of solutions for energy storage in case of self-consumption. The next article briefly presents the Elsa project (financed by the EU) which gives a second life to electric vehicle batteries by developing an energy storage and control solution for professionals. A system developed by French researchers is briefly presented: it aims at producing electricity, at storing it, and at using it to supply isolated autonomous systems. The idea developed in a published study is then discussed: to use electric vehicle batteries to store the intermittent energy produced by renewable sources. The last article comments the integration by Enedis of intelligent devices into the grid
Innovation on Smart Grids and energy storage. IA Special; Innovation on Smart Grids and energy storage. IA Special

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-11-15

In this special edition of the Innovation Network Attache a large number of short articles on aspects of ICT aspects of intellligent energy networks, the security and integrity of the use and control of those networks, and energy storage. In this special an overview is given of the most important developments in Israel, Russian Federation, Brazil, Netherlands, France, Germany, Singapore, Japan, Taiwan, China, South Korea, India, United States and Canada [Dutch] In deze special van het Innovation Attache Netwerk een groot aantal korte artikelen over de ICT aspecten van intellligente energie netten, de veiligheid en integriteit van het gebruik en sturing ervan, en energie opslag. In de special een overzicht van in het oog springende ontwikkelingen in de landen Israel, Rusland, Brazilie, Nederland, Frankrijk, Duitsland, Singapore, Japan, Taiwan, China, Zuid-Korea, India, Verenigde Staten en Canada.
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.
An adaptive short-term prediction scheme for wind energy storage management

International Nuclear Information System (INIS)

Blonbou, Ruddy; Monjoly, Stephanie; Dorville, Jean-Francois

2011-01-01

Research highlights: → We develop a real time algorithm for grid-connected wind energy storage management. → The method aims to guarantee, with ±5% error margin, the power sent to the grid. → Dynamic scheduling of energy storage is based on short-term energy prediction. → Accurate predictions reduce the need in storage capacity. -- Abstract: Efficient forecasting scheme that includes some information on the likelihood of the forecast and based on a better knowledge of the wind variations characteristics along with their influence on power output variation is of key importance for the optimal integration of wind energy in island's power system. In the Guadeloupean archipelago (French West-Indies), with a total wind power capacity of 25 MW; wind energy can represent up to 5% of the instantaneous electricity production. At this level, wind energy contribution can be equivalent to the current network primary control reserve, which causes balancing difficult. The share of wind energy is due to grow even further since the objective is set to reach 118 MW by 2020. It is an absolute evidence for the network operator that due to security concerns of the electrical grid, the share of wind generation should not increase unless solutions are found to solve the prediction problem. The University of French West-Indies and Guyana has developed a short-term wind energy prediction scheme that uses artificial neural networks and adaptive learning procedures based on Bayesian approach and Gaussian approximation. This paper reports the results of the evaluation of the proposed approach; the improvement with respect to the simple persistent prediction model was globally good. A discussion on how such a tool combined with energy storage capacity could help to smooth the wind power variation and improve the wind energy penetration rate into island utility network is also proposed.
Energy storage

Energy Technology Data Exchange (ETDEWEB)

1962-07-01

The papers on energy storage problems, given to the United Nations Conference on New Sources of Energy, Rome, 1961, are reviewed. Many aspects of the subject are discussed: comparisons between the costs of storing energy in batteries and in fuel cells; the use, efficiency and expected improvement of fuel cells; the principles involved in the chemical conversion of solar energy to chemical energy; the use of metal hydride fuel cells; the chemical conversion and storage of concentrated solar energy for which the solar furnace is used for photochemical reactions. Finally, the general costs of storing energy in any form and delivering it are analyzed with particular reference to storage batteries and fuel cells.
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.

2018-01-01

of their installed capacity whereas the second one modifies the BESs performance in terms of their state of charge (SoC) to prevent the excessive saturation or depletion of batteries. The proposed controller enables the effective use of storage capacity in different conditions. Finally, the simulation results based...... 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...
Logistical networking: a global storage network

International Nuclear Information System (INIS)

Beck, Micah; Moore, Terry

2005-01-01

The absence of an adequate distributed storage infrastructure for data buffering has become a significant impediment to the flow of work in the wide area, data intensive collaborations that are increasingly characteristic of leading edge research in several fields. One solution to this problem, pioneered under DOE's SciDAC program, is Logistical Networking, which provides a framework for a globally scalable, maximally interoperable storage network based on the Internet Backplane Protocol (IBP). This paper provides a brief overview of the Logistical Networking (LN) architecture, the middleware developed to exploit its value, and a few of the applications that some of research communities have made of it
Study of the potential of energy storage - Investigation report - Synthesis

International Nuclear Information System (INIS)

Renaud, Arnaud; Fournie, Laurent; Girardeau, Pierre; Chammas, Maxime; Tarel, Guillaume; Chiche, Alice; De Freminville; Pierre; Lacroix, Olivier; Rakotojaona, Loic; Payen, Luc; Riu, Delphine; Kerouedan, Anne-Fleur

2013-01-01

The objective of this study is to assess, for France and its overseas territories, the potential of energy storage by 2030, and to identify the technological sectors which are the most economically relevant. A global surplus has been calculated, as well as the benefit from additional storage capacities. This benefit has been compared with cost predictions by 2030 for different storage technologies. Economically viable powers and types of energy storages are assessed with respect to different scenarios, and impacts in terms of associated jobs are assessed. The document reports and discusses the surplus assessment for the community, describes the various services provided by energy storage, presents the modelling scenarios and hypotheses, discusses the main results of valorisation for the community, presents the various energy storage technologies (gravity, thermodynamic, electrochemical, electrostatic, inertial, latent thermal, thermo-chemical, and power to gas), presents business models and deployment potential for different applications (mass storage of electricity in France, electricity storage in a non-connected area, decentralised electricity storage as a response to grid congestion, valorisation of an electricity storage, thermal storage on a heat network, cold storage, management of diffuse demand of hot water), and discusses implications regarding employment
Vision of future energy networks - Final report; Vision of future energy networks - Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Froehlich, K.; Andersson, G.

2008-07-01

In the framework of the project 'Vision of Future Networks', models and methods have been developed that enable a greenfield approach for energy systems with multiple energy carriers. Applying a greenfield approach means that no existing infrastructure is taken into account when designing the energy system, i.e. the system is virtually put up on a green field. The developed models refer to the impacts of energy storage on power systems with stochastic generation, to the integrated modelling and optimization of multi-carrier energy systems, to reliability considerations of future energy systems as well as to possibilities of combined transmission of multiple energy carriers. Key concepts, which have been developed in the framework of this project, are the Energy Hub (for the conversion and storage of energy) and the Energy Interconnector (for energy transmission). By means of these concepts, it is possible to design structures for future energy systems being able to cope with the growing requirements regarding energy supply. (author)
The flywheel as an energy storage device in railway and tram networks; Schwungrad als Energiespeicher in Bahnnetzen. Erfahrungen aus einem Versuchsprojekt in der Stadt Zuerich

Energy Technology Data Exchange (ETDEWEB)

Bischof, M. [EWZ, Zuerich (Switzerland)

2010-07-01

This article reviews experience made with a flywheel-based energy storage system that was tested on part of Zurich's tram network. The aim of the six weeks of tests was to determine how much energy that is generated by the recuperation of braking energy can be temporarily stored to provide power for accelerating trams on the network. The article discusses the valuable knowledge gained during the tests. The basic ideas behind the tests and the goals aimed for are discussed, both concerning energy balances as well as other factors such as noise and electromagnetic emissions. The part of the tram line used for the tests is described and the results are discussed. Other power storage systems using flywheels and capacitors are reviewed.
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.
The state of energy storage in electric utility systems and its effect on renewable energy resources

Energy Technology Data Exchange (ETDEWEB)

Rau, N S

1994-08-01

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

Science.gov (United States)

Wicki, Samuel; Hansen, Erik G

2017-09-20

The emergence and diffusion of green and sustainable technologies is full of obstacles and has therefore become an important area of research. We are interested in further understanding the dynamics between entrepreneurial experimentation, market formation, and institutional contexts, together playing a decisive role for successful diffusion of such technologies. Accordingly, we study these processes by adopting a technological innovation system perspective focusing on actors, networks, and institutions as well as the functions provided by them. Using a qualitative case study research design, we focus on the high-speed flywheel energy storage technology. As flywheels are based on a rotating mass allowing short-term storage of energy in kinetic form, they represent an environmentally-friendly alternative to electrochemical batteries and therefore can play an important role in sustainable energy transitions. Our contribution is threefold: First , regarding the flywheel energy storage technology, our findings reveal two subsystems and related markets in which development took different courses. In the automotive sector, flywheels are developing well as a braking energy recovery technology under the influence of two motors of innovation. In the electricity sector, they are stagnating at the stage of demonstration projects because of two important system weaknesses that counteract demand for storage. Second , we contribute to the theory of technological innovation systems by better understanding the internal dynamics between different functions of an innovation system as well as between the innovation system and its (external) contextual structures. Our third contribution is methodological. According to our best knowledge, we are the first to use system dynamics to (qualitatively) analyze and visualize dynamics between the diverse functions of innovation systems with the aim of enabling a better understanding of complex and iterative system processes. The paper also
Impacts of optimal energy storage deployment and network reconfiguration on renewable integration level in distribution systems

International Nuclear Information System (INIS)

Santos, Sérgio F.; Fitiwi, Desta Z.; Cruz, Marco R.M.; Cabrita, Carlos M.P.; Catalão, João P.S.

2017-01-01

Highlights: • A dynamic and multi-objective stochastic mixed integer linear programming model is developed. • A new mechanism to quantify the impacts of network flexibility and ESS deployments on RES integration is presented. • Optimal integration of ESSs dramatically increases the level and the optimal exploitation of renewable DGs. • As high as 90% of RES integration level may be possible in distribution network systems. • Joint DG and ESS installations along with optimal network reconfiguration greatly contribute to voltage stability. - Abstract: Nowadays, there is a wide consensus about integrating more renewable energy sources-RESs to solve a multitude of global concerns such as meeting an increasing demand for electricity, reducing energy security and heavy dependence on fossil fuels for energy production, and reducing the overall carbon footprint of power production. Framed in this context, the coordination of RES integration with energy storage systems (ESSs), along with the network’s switching capability and/or reinforcement, is expected to significantly improve system flexibility, thereby increasing the capability of the system in accommodating large-scale RES power. Hence, this paper presents a novel mechanism to quantify the impacts of network switching and/or reinforcement as well as deployment of ESSs on the level of renewable power integrated in the system. To carry out this analysis, a dynamic and multi-objective stochastic mixed integer linear programming (S-MILP) model is developed, which jointly takes the optimal deployment of RES-based DGs and ESSs into account in coordination with distribution network reinforcement and/or reconfiguration. The IEEE 119-bus test system is used as a case study. Numerical results clearly show the capability of ESS deployment in dramatically increasing the level of renewable DGs integrated in the system. Although case-dependent, the impact of network reconfiguration on RES power integration is not

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...
A New Pricing Scheme for Controlling Energy Storage Devices in Future Smart Grid

OpenAIRE

Zhu, Jingwei; Chen, Michael Z. Q.; Du, Baozhu

2014-01-01

Improvement of the overall efficiency of energy infrastructure is one of the main anticipated benefits of the deployment of smart grid technology. Advancement in energy storage technology and two-way communication in the electric network are indispensable components to achieve such a vision, while efficient pricing schemes and appropriate storage management are also essential. In this paper, we propose a universal pricing scheme which permits one to indirectly control the energy storage devic...
Deployment strategy for battery energy storage system in distribution network based on voltage violation regulation

Science.gov (United States)

Wu, H.; Zhou, L.; Xu, T.; Fang, W. L.; He, W. G.; Liu, H. M.

2017-11-01

In order to improve the situation of voltage violation caused by the grid-connection of photovoltaic (PV) system in a distribution network, a bi-level programming model is proposed for battery energy storage system (BESS) deployment. The objective function of inner level programming is to minimize voltage violation, with the power of PV and BESS as the variables. The objective function of outer level programming is to minimize the comprehensive function originated from inner layer programming and all the BESS operating parameters, with the capacity and rated power of BESS as the variables. The differential evolution (DE) algorithm is applied to solve the model. Based on distribution network operation scenarios with photovoltaic generation under multiple alternative output modes, the simulation results of IEEE 33-bus system prove that the deployment strategy of BESS proposed in this paper is well adapted to voltage violation regulation invariable distribution network operation scenarios. It contributes to regulating voltage violation in distribution network, as well as to improve the utilization of PV systems.
Mass storage technology in networks

Science.gov (United States)

Ishii, Katsunori; Takeda, Toru; Itao, Kiyoshi; Kaneko, Reizo

1990-08-01

Trends and features of mass storage subsystems in network are surveyed and their key technologies spotlighted. Storage subsystems are becoming increasingly important in new network systems in which communications and data processing are systematically combined. These systems require a new class of high-performance mass-information storage in order to effectively utilize their processing power. The requirements of high transfer rates, high transactional rates and large storage capacities, coupled with high functionality, fault tolerance and flexibility in configuration, are major challenges in storage subsystems. Recent progress in optical disk technology has resulted in improved performance of on-line external memories to optical disk drives, which are competing with mid-range magnetic disks. Optical disks are more effective than magnetic disks in using low-traffic random-access file storing multimedia data that requires large capacity, such as in archive use and in information distribution use by ROM disks. Finally, it demonstrates image coded document file servers for local area network use that employ 130mm rewritable magneto-optical disk subsystems.
Energy Storage and Smart Energy Systems

Directory of Open Access Journals (Sweden)

Poul Alberg Østergaard

2016-12-01

Full Text Available 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 be disregarded but that it will be needed for other purposes in the future.
Some wind-energy storage options

Energy Technology Data Exchange (ETDEWEB)

Eldridge, F R; Ljungstroem, O [ed.

1976-01-01

Systems capable of storing energy generated from the wind can be categorized in terms of electrochemical energy storage systems, thermal energy storage systems, kinetic energy systems, and potential energy systems. Recent surveys of energy storage systems have evaluated some of these available storage technologies in terms of the minimum economic sizes for utility applications, estimated capital costs of these units, expected life, dispersed storage capabilities, and estimated turn-around efficiencies of the units. These are summarized for various types of energy storage options.
Energy and exergy analyses of an ice-on-coil thermal energy storage system

International Nuclear Information System (INIS)

Ezan, Mehmet Akif; Erek, Aytunç; Dincer, Ibrahim

2011-01-01

In this study, energy and exergy analyses are carried out for the charging period of an ice-on-coil thermal energy storage system. The present model is developed using a thermal resistance network technique. First, the time-dependent variations of the predicted total stored energy, mass of ice, and outlet temperature of the heat transfer fluid from a storage tank are compared with the experimental data. Afterward, performance of an ice-on-coil type latent heat thermal energy storage system is investigated for several working and design parameters. The results of a comparative study are presented in terms of the variations of the heat transfer rate, total stored energy, dimensionless energetic/exergetic effectiveness and energy/exergy efficiency. The results indicate that working and design parameters of the ice-on-coil thermal storage tank should be determined by considering both energetic and exergetic behavior of the system. For the current parameters, storage capacity and energy efficiency of the system increases with decreasing the inlet temperature of the heat transfer fluid and increasing the length of the tube. Besides, the exergy efficiency increases with increasing the inlet temperature of the heat transfer fluid and increasing the length of the tube. -- Highlights: ► A comprehensive study on energy and exergy analyses of an ice-on-coil TES system. ► Determination of irreversibilities and their potential sources. ► Evaluation of both energy and exergy efficiencies and their comparisons.
Superconducting magnetic energy storage for electric utilities and fusion systems

International Nuclear Information System (INIS)

Rogers, J.D.; Boenig, H.J.; Hassenzahl, W.V.

1978-01-01

Superconducting inductors provide a compact and efficient means of storing electrical energy without an intermediate conversion process. Energy storage inductors are under development for load leveling and transmission line stabilization in electric utility systems and for driving magnetic confinement and plasma heating coils in fusion energy systems. Fluctuating electric power demands force the electric utility industry to have more installed generating capacity than the average load requires. Energy storage can increase the utilization of base-load fossil and nuclear power plants for electric utilities. The Los Alamos Scientific Laboratory and the University of Wisconsin are developing superconducting magnetic energy storage (SMES) systems, which will store and deliver electrical energy for load leveling, peak shaving, and the stabilization of electric utility networks. In the fusion area, inductive energy transfer and storage is being developed. Both 1-ms fast-discharge theta-pinch systems and 1-to-2-s slow energy transfer tokamak systems have been demonstrated. The major components and the method of operation of a SMES unit are described, and potential applications of different size SMES systems in electric power grids are presented. Results are given of a reference design for a 10-GWh unit for load leveling, of a 30-MJ coil proposed for system stabilization, and of tests with a small-scale, 100-kJ magnetic energy storage system. The results of the fusion energy storage and transfer tests are presented. The common technology base for the various storage systems is discussed
Integration of Decentralized Thermal Storages Within District Heating (DH Networks

Directory of Open Access Journals (Sweden)

Schuchardt Georg K.

2016-12-01

Full Text Available Thermal Storages and Thermal Accumulators are an important component within District Heating (DH systems, adding flexibility and offering additional business opportunities for these systems. Furthermore, these components have a major impact on the energy and exergy efficiency as well as the heat losses of the heat distribution system. Especially the integration of Thermal Storages within ill-conditioned parts of the overall DH system enhances the efficiency of the heat distribution. Regarding an illustrative and simplified example for a DH system, the interactions of different heat storage concepts (centralized and decentralized and the heat losses, energy and exergy efficiencies will be examined by considering the thermal state of the heat distribution network.
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
Viability of using energy storage for frequency regulation on power grid

Science.gov (United States)

Lim, Y. S.; Hau, L. C.; Loh, K. Y.; Lim, K. Y.; Lyons, P. F.; Taylor, P. C.

2018-05-01

This project is about the development and integration of a real-time network simulator in the laboratory using hardware in the loop (HIL) for the purpose of frequency regulation. Frequency regulation is done using the energy storage system (ESS) and a real-time network test bed developed in the smart energy laboratory in Newcastle University. An IEEE Test System was built in the OPAL-RT network simulator to mimic the power grid with renewable energy sources. The study demonstrates the viability of using an ESS to regulate the frequency under an increased penetration of renewable energy sources.
Agent based modeling of energy networks

International Nuclear Information System (INIS)

Gonzalez de Durana, José María; Barambones, Oscar; Kremers, Enrique; Varga, Liz

2014-01-01

Highlights: • A new approach for energy network modeling is designed and tested. • The agent-based approach is general and no technology dependent. • The models can be easily extended. • The range of applications encompasses from small to large energy infrastructures. - Abstract: Attempts to model any present or future power grid face a huge challenge because a power grid is a complex system, with feedback and multi-agent behaviors, integrated by generation, distribution, storage and consumption systems, using various control and automation computing systems to manage electricity flows. Our approach to modeling is to build upon an established model of the low voltage electricity network which is tested and proven, by extending it to a generalized energy model. But, in order to address the crucial issues of energy efficiency, additional processes like energy conversion and storage, and further energy carriers, such as gas, heat, etc., besides the traditional electrical one, must be considered. Therefore a more powerful model, provided with enhanced nodes or conversion points, able to deal with multidimensional flows, is being required. This article addresses the issue of modeling a local multi-carrier energy network. This problem can be considered as an extension of modeling a low voltage distribution network located at some urban or rural geographic area. But instead of using an external power flow analysis package to do the power flow calculations, as used in electric networks, in this work we integrate a multiagent algorithm to perform the task, in a concurrent way to the other simulation tasks, and not only for the electric fluid but also for a number of additional energy carriers. As the model is mainly focused in system operation, generation and load models are not developed
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.
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.
Advanced Graphene-Based Binder-Free Electrodes for High-Performance Energy Storage.

Science.gov (United States)

Ji, Junyi; Li, Yang; Peng, Wenchao; Zhang, Guoliang; Zhang, Fengbao; Fan, Xiaobin

2015-09-23

The increasing demand for energy has triggered tremendous research effort for the development of high-performance and durable energy-storage devices. Advanced graphene-based electrodes with high electrical conductivity and ion accessibility can exhibit superior electrochemical performance in energy-storage devices. Among them, binder-free configurations can enhance the electron conductivity of the electrode, which leads to a higher capacity by avoiding the addition of non-conductive and inactive binders. Graphene, a 2D material, can be fabricated into a porous and flexible structure with an interconnected conductive network. Such a conductive structure is favorable for both electron and ion transport to the entire electrode surface. In this review, the main processes used to prepare binder-free graphene-based hybrids with high porosity and well-designed electron conductive networks are summarized. Then, the applications of free-standing binder-free graphene-based electrodes in energy-storage devices are discussed. Future research aspects with regard to overcoming the technological bottlenecks are also proposed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Contemporary energy storage sources. Energy saving

International Nuclear Information System (INIS)

Manev, Veselin

2011-01-01

The development of renewable energy system for electricity production is impede because of needs to be stabilized with nearly equivalent installed power of energy storage devices. The development of more electrical energy storage facilities will be extremely important for electricity generation in the future. Using hydro pumping, combined with a long life and fast charge/discharge rate, highly efficient contemporary power energy storage as Altairnano lithium ion battery, currently is seems to be the best solution for fast penetration rate of wind and solar energy systems
Integrated electrification solution for autonomous electrical networks on the basis of RES and energy storage configurations

International Nuclear Information System (INIS)

Kaldellis, J.K.

2008-01-01

Most medium and small islands of the Aegean Archipelagos face serious infrastructure problems, strongly related with the limited electrical energy available at extremely high cost. On the other hand, the area is characterized by very high wind speeds and abundant solar energy, thus the exploitation of the available renewable energy sources (RES) may significantly contribute to the fulfillment of the local societies energy demand at minimum environmental and macroeconomic cost. However, the stochastic availability of wind energy and the variable availability of solar energy, the daily and seasonal electricity demand fluctuations, as well as the limited local electrical network capacity result in serious restrictions concerning the maximum renewable power penetration. In this context, the present paper investigates the possibility of creating a combined electricity generation facility based on the exploitation of wind or/and solar potential of an area as well as on the utilization of an appropriate energy storage configuration in order to replace the existing thermal power stations with rational investment requirements. For this purpose, the major parameters of the proposed integrated configuration are firstly calculated and its financial viability is accordingly analyzed. One of the main targets of the proposed solution is to maximize the RES exploitation of the area at a minimum electricity generation cost, while special emphasis is given in order to select the most cost-efficient energy storage device available. According to the results obtained the proposed solution is not only financially attractive but also improves the quality of the electricity offered to the local communities, substituting the expensive and heavily polluting existing thermal power stations
Advanced materials for energy storage

Energy Technology Data Exchange (ETDEWEB)

Liu, Chang; Li, Feng; Ma, Lai-Peng; Cheng, Hui-Ming [Shenyang National Laboratory for Materials Science Institute of Metal Research, Chinese Academy of Sciences 72 Wenhua Road, Shenyang 110016 (China)

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. (Abstract Copyright [2010], Wiley Periodicals, Inc.)
Towards Integrating Distributed Energy Resources and Storage Devices in Smart Grid.

Science.gov (United States)

Xu, Guobin; Yu, Wei; Griffith, David; Golmie, Nada; Moulema, Paul

2017-02-01

Internet of Things (IoT) provides a generic infrastructure for different applications to integrate information communication techniques with physical components to achieve automatic data collection, transmission, exchange, and computation. The smart grid, as one of typical applications supported by IoT, denoted as a re-engineering and a modernization of the traditional power grid, aims to provide reliable, secure, and efficient energy transmission and distribution to consumers. How to effectively integrate distributed (renewable) energy resources and storage devices to satisfy the energy service requirements of users, while minimizing the power generation and transmission cost, remains a highly pressing challenge in the smart grid. To address this challenge and assess the effectiveness of integrating distributed energy resources and storage devices, in this paper we develop a theoretical framework to model and analyze three types of power grid systems: the power grid with only bulk energy generators, the power grid with distributed energy resources, and the power grid with both distributed energy resources and storage devices. Based on the metrics of the power cumulative cost and the service reliability to users, we formally model and analyze the impact of integrating distributed energy resources and storage devices in the power grid. We also use the concept of network calculus, which has been traditionally used for carrying out traffic engineering in computer networks, to derive the bounds of both power supply and user demand to achieve a high service reliability to users. Through an extensive performance evaluation, our data shows that integrating distributed energy resources conjointly with energy storage devices can reduce generation costs, smooth the curve of bulk power generation over time, reduce bulk power generation and power distribution losses, and provide a sustainable service reliability to users in the power grid.
Improving the network infeed accuracy of non-dispatchable generators with energy storage devices

International Nuclear Information System (INIS)

Koeppel, Gaudenz; Korpaas, Magnus

2008-01-01

The power output of generators based on renewable energy sources is often difficult to predict due to the non-deterministic behaviour of the energy source. Particularly in the case of wind turbines this leads to unpredicted line loading and requires balancing energy, at relatively high costs, depending on market structures. Consequently, the income from the production from such non-dispatchable generators can be significantly reduced by the penalty costs incurred. This paper investigates the potential of operating an energy storage device in parallel with the non-dispatchable generator in order to compensate the inaccuracies of the forecasted infeed and to avoid infeed deviations. A time series based simulation methodology is discussed, suitable for any type of non-dispatchable generator. The methodology contains a procedure for simulating different forecast errors, applying an exponentially weighted moving average approach. Analysis procedures and system performance indices are introduced for the evaluation of the configuration's performance. The applicability is shown in two case studies, using measurement data from a wind turbine and from a photovoltaic system. Both case studies show that the suggested configuration considerably improves the reliability or dependability of the network infeed, in turn reducing the demand for balancing energy and back-up generation. The relation between forecast error magnitude and required energy capacity is identified and the coherence of the time series analysis is discussed. (author)

Stationary centrifugal mass energy storage at the Hamburg subway; Stationaerer Schwungmassen-Energiespeicher bei der Hamburger U-Bahn

Energy Technology Data Exchange (ETDEWEB)

Steinhorst, F. [Hamburger Hochbahn AG, Hamburg (Germany). Abt. Energieanlagen; Jonassen, I.; Peters, A. [Hamburger Hochbahn AG, Hamburg (Germany). Fachbereich Energieversorgung

2008-07-01

A stationary energy storage is to be used as a model in a substation of the Hamburg subway network with a view to the environmentally compatible and technically proper use of the brake energy available in electrified local public transport systems. A further question to be reviewed is whether the use of other energy storages in the subway network is a reasonable solution. (orig.)
The SERI solar energy storage program

Science.gov (United States)

Copeland, R. J.; Wright, J. D.; Wyman, C. E.

1980-01-01

In support of the DOE thermal and chemical energy storage program, the solar energy storage program (SERI) provides research on advanced technologies, systems analyses, and assessments of thermal energy storage for solar applications in support of the Thermal and Chemical Energy Storage Program of the DOE Division of Energy Storage Systems. Currently, research is in progress on direct contact latent heat storage and thermochemical energy storage and transport. Systems analyses are being performed of thermal energy storage for solar thermal applications, and surveys and assessments are being prepared of thermal energy storage in solar applications. A ranking methodology for comparing thermal storage systems (performance and cost) is presented. Research in latent heat storage and thermochemical storage and transport is reported.
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.
Design of the energy storage system for the High Energy Gas Laser Facility at LASL

International Nuclear Information System (INIS)

Riepe, K.B.; Kircher, M.J.

1977-01-01

The Antares laser is being built in the High Energy Gas Laser Facility (HEGLF) at Los Alamos to continue laser fusion experiments at very high power. The laser medium will be pumped by an electrical discharge, which requires an energy input of about 5 MJ in a few microseconds at about 500 kV. The energy storage system which will provide the pulsed power will be a bank of high-voltage pulse-forming networks. Tradeoff studies have been performed comparing the performance of multi-mesh networks with single-mesh networks. The single-mesh network requires about 20% more energy than a two-mesh network, but will tolerate three times the inductance of a two-mesh network. Analysis also shows that amplifier gain is not sensitive to impedance mismatch among the pulse-forming network, the transmission cables, and the gas discharge. A prototype pulse-forming network is being built to test components and trigger performance. It is a Marx generator storing 300 kJ at 1.2 MV open circuit, with 3 μH internal inductance
ERDA's Chemical Energy Storage Program

Science.gov (United States)

Swisher, J. H.; Kelley, J. H.

1977-01-01

The Chemical Energy Storage Program is described with emphasis on hydrogen storage. Storage techniques considered include pressurized hydrogen gas storage, cryogenic liquid hydrogen storage, storage in hydride compounds, and aromatic-alicyclic hydrogen storage. Some uses of energy storage are suggested. Information on hydrogen production and hydrogen use is also presented. Applications of hydrogen energy systems include storage of hydrogen for utilities load leveling, industrial marketing of hydrogen both as a chemical and as a fuel, natural gas supplementation, vehicular applications, and direct substitution for natural gas.
Optimal Scheduling of a Multi-Carrier Energy Hub Supplemented By Battery Energy Storage Systems

DEFF Research Database (Denmark)

Javadi, Mohammad Sadegh; Anvari-Moghaddam, Amjad; Guerrero, Josep M.

2017-01-01

This paper introduces a management model for optimal scheduling of a multi-carrier energy hub. In the proposed hub, three types of assets are considered: dispersed generating systems (DGs) such as micro-combined heat and power (mCHP) units, storage devices such as battery-based electrical storage...... systems (ESSs), and heating/cooling devices such as electrical heater, heat-pumps and absorption chillers. The optimal scheduling and management of the examined energy hub assets in line with electrical transactions with distribution network is modeled as a mixed-integer non-linear optimization problem....... In this regard, optimal operating points of DG units as well as ESSs are calculated based on a cost-effective strategy. Degradation cost of ESSs is also taken into consideration for short-term scheduling. Simulation results demonstrate that including well-planned energy storage options together with optimal...
Flywheel energy storage; Schwungmassenspeicher

Energy Technology Data Exchange (ETDEWEB)

Bornemann, H.J. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany)

1996-12-31

Energy storages may be chemical systems such as batteries, thermal systems such as hot-water tanks, electromagnetic systems such as capacitors and coils, or mechanical systems such as pumped storage power systems or flywheel energy storages. In flywheel energy storages the energy is stored in the centrifugal mass in the form of kinetic energy. This energy can be converted to electricity via a motor/generator unit and made available to the consumer. The introduction of magnetic bearings has greatly enhanced the potential of flywheel energy storages. As there is no contact between the moving parts of magnetic bearings, this technology provides a means of circumventing the engineering and operational problems involved in the we of conventional bearings (ball, roller, plain, and gas bearings). The advantages of modern flywheel energy storages over conventional accumulators are an at least thousandfold longer service life, low losses during long-time storage, greater power output in the case of short-time storage, and commendable environmental benignity. (orig./HW) [Deutsch] Als Enegiespeicher kommen chemische Systeme, z.B. Batterien, thermische Systeme, z.B. Warmwassertanks, elektromagnetische Systeme, z.B. Kondensatoren und Spulen, sowie mechanische Systeme, z.B. Pumpspeicherwerke und Schwungmassenspeicher in Frage. In einem Schwungmassenspeicher wird Energie in Form von kinetischer Energie in der Schwungmasse gespeichert. Ueber eine Moter/Generator Einheit wird diese Energie in elektrischen Strom umgewandelt und dem Verbraucher zugefuehrt. Mit der Einfuehrung von magnetischen Lagern konnte die Leistungsfaehigkeit von Schwungmassenspeichern erheblich gesteigert werden. Da in einem Magnetlager keine Beruehrung zwischen sich bewegenden Teilen besteht, wird ein Grossteil der mit dem Einsatz konventioneller Lager (Kugel- und Rollenlager, Gleitlager und Gaslager) verbundenen ingenieurtechnischen und betriebstechnischen Probleme vermieden. Die Vorteile von modernen
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.
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.
A New Pricing Scheme for Controlling Energy Storage Devices in Future Smart Grid

Directory of Open Access Journals (Sweden)

Jingwei Zhu

2014-01-01

Full Text Available Improvement of the overall efficiency of energy infrastructure is one of the main anticipated benefits of the deployment of smart grid technology. Advancement in energy storage technology and two-way communication in the electric network are indispensable components to achieve such a vision, while efficient pricing schemes and appropriate storage management are also essential. In this paper, we propose a universal pricing scheme which permits one to indirectly control the energy storage devices in the grid to achieve a more desirable aggregate demand profile that meets a particular target of the grid operator such as energy generation cost minimization and carbon emission reduction. Such a pricing scheme can potentially be applied to control the behavior of energy storage devices installed for integration of intermittent renewable energy sources that have permission to grid connection and will have broader applications as an increasing number of novel and low-cost energy storage technologies emerge.
Energy storage. A challenge for energy transition

International Nuclear Information System (INIS)

Bart, Jean-Baptiste; Nekrasov, Andre; Pastor, Emmanuel; Benefice, Emmanuel; Brincourt, Thierry; Brisse, Annabelle; Cagnac, Albannie; Delille, Gauthier; Hinchliffe, Timothee; Lancel, Gilles; Jeandel, Elodie; Lefebvre, Thierry; Loevenbruck, Philippe; Penneau, Jean-Francois; Soler, Robert; Stevens, Philippe; Radvanyi, Etienne; Torcheux, Laurent

2017-06-01

Written by several EDF R and D engineers, this book aims at presenting an overview of knowledge and know-how of EDF R and D in the field of energy storage, and at presenting the different technologies and their application to electric power systems. After a description of the context related to a necessary energy transition, the authors present the numerous storage technologies. They distinguish direct storage of power (pumped storage water stations, compressed air energy storage, flywheels, the various electrochemical batteries, metal-air batteries, redox flow batteries, superconductors), thermal storage (power to heat, heat to power) and hydrogen storage (storage under different forms), and propose an overview of the situation of standardisation of storage technologies. In the next part, they give an overview of the main services provided by storage to the electric power system: production optimisation, frequency adjustment, grid constraint resolution, local smoothing of PV and wind production, supply continuity. The last part discusses perspectives regarding the role of tomorrow's storage in the field of electrical mobility, for emerging markets, and with respect to different scenarios
Energy analysis of thermal energy storages with grid configurations

International Nuclear Information System (INIS)

Rezaie, Behnaz; Reddy, Bale V.; Rosen, Marc A.

2014-01-01

Highlights: • Grid configurations of TESs are developed and assessed. • Characteristics of various configurations of TESs are developed as functions of properties. • Functions for the discharge temperature and the discharge energy of the TES are developed. - Abstract: In some thermal networks like district energy systems, there can exist conditions, depending on space availability, economics, project requirements, insulation, storing media type and other issues, for which it may be advantageous to utilize several thermal energy storages (TESs) instead of one. Here, various configurations for multiple TESs are proposed and investigated. Significant parameters for a TES, or a set of TESs, include discharging temperature and recovered energy. First, one TES is modeled to determine the final temperature, energy recovery, and energy efficiency. Next, characteristics for various grid configurations of multiple TESs are developed as functions of TES characteristics (e.g., charging and discharging temperatures and energy quantities). Series, parallel and comprehensive grid TES configurations are considered. In the parallel configuration, the TESs behave independently. This suggests that the TES can consist of different storage media types and sizes, and that there is no restriction on initial temperature of the TES. In the series configuration, the situation is different because the TESs are connected directly or indirectly through a heat exchanger. If there is no heat exchanger between the TESs, the TES storage media should be the same, because the outlet of one TES in the series is the inlet to the next. The initial temperature of the second TES must be smaller than the discharge temperature of the first. There is no restriction on the TES size for series configurations. The general grid configuration is observed to exhibit characteristics of both series and parallel configurations
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.
Demonstration of Hydrogen Energy Network and Fuel Cells in Residential Homes

International Nuclear Information System (INIS)

Hirohisa Aki; Tetsuhiko Maeda; Itaru Tamura; Akeshi Kegasa; Yoshiro Ishikawa; Ichiro Sugimoto; Itaru Ishii

2006-01-01

The authors proposed the setting up of an energy interchange system by establishing energy networks of electricity, hot water, and hydrogen in residential homes. In such networks, some homes are equipped with fuel cell stacks, fuel processors, hydrogen storage devices, and large storage tanks for hot water. The energy network enables the flexible operation of the fuel cell stacks and fuel processors. A demonstration project has been planned in existing residential homes to evaluate the proposal. The demonstration will be presented in a small apartment building. The building will be renovated and will be equipped with a hydrogen production facility, a hydrogen interchange pipe, and fuel cell stacks with a heat recovery device. The energy flow process from hydrogen production to consumption in the homes will be demonstrated. This paper presents the proposed energy interchange system and demonstration project. (authors)
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.
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...
Solar applications analysis for energy storage

Science.gov (United States)

Blanchard, T.

1980-01-01

The role of energy storage as it relates to solar energy systems is considered. Storage technologies to support solar energy applications, the status of storage technologies, requirements and specifications for storage technologies, and the adequacy of the current storage research and development program to meet these requirements are among the factors discussed. Emphasis is placed on identification of where the greatest potential exists for energy storage in support of those solar energy systems which could have a significant impact on the U.S. energy mix.
Modeling and Control of Heat Networks with Storage : the Single-Producer Multiple-Consumer Case

NARCIS (Netherlands)

Scholten, Tjeert Wobko; De Persis, Claudio; Tesi, Pietro

2015-01-01

In heat networks, energy storage is a viable approach to balance demand and supply. In such a network, a heat carrier is used in the form of water, where heat is injected and extracted through heat exchangers. The network can transport and store heated water in stratification tanks to shift loads in
Modeling and control of heat networks with storage: The single-producer multiple-consumer case.

NARCIS (Netherlands)

Scholten, Tjardo; De Persis, Claudio; Tesi, Pietro

2015-01-01

In heat networks, energy storage is a viable approach to balance demand and supply. In such a network, a heat carrier is used in the form of water, where heat is injected and extracted through heat exchangers. The network can transport and store heated water in stratification tanks to shift loads in
The Role of Energy Reservoirs in Distributed Computing: Manufacturing, Implementing, and Optimizing Energy Storage in Energy-Autonomous Sensor Nodes

Science.gov (United States)

Cowell, Martin Andrew

The world already hosts more internet connected devices than people, and that ratio is only increasing. These devices seamlessly integrate with peoples lives to collect rich data and give immediate feedback about complex systems from business, health care, transportation, and security. As every aspect of global economies integrate distributed computing into their industrial systems and these systems benefit from rich datasets. Managing the power demands of these distributed computers will be paramount to ensure the continued operation of these networks, and is elegantly addressed by including local energy harvesting and storage on a per-node basis. By replacing non-rechargeable batteries with energy harvesting, wireless sensor nodes will increase their lifetimes by an order of magnitude. This work investigates the coupling of high power energy storage with energy harvesting technologies to power wireless sensor nodes; with sections covering device manufacturing, system integration, and mathematical modeling. First we consider the energy storage mechanism of supercapacitors and batteries, and identify favorable characteristics in both reservoir types. We then discuss experimental methods used to manufacture high power supercapacitors in our labs. We go on to detail the integration of our fabricated devices with collaborating labs to create functional sensor node demonstrations. With the practical knowledge gained through in-lab manufacturing and system integration, we build mathematical models to aid in device and system design. First, we model the mechanism of energy storage in porous graphene supercapacitors to aid in component architecture optimization. We then model the operation of entire sensor nodes for the purpose of optimally sizing the energy harvesting and energy reservoir components. In consideration of deploying these sensor nodes in real-world environments, we model the operation of our energy harvesting and power management systems subject to

Research progress about chemical energy storage of solar energy

Science.gov (United States)

Wu, Haifeng; Xie, Gengxin; Jie, Zheng; Hui, Xiong; Yang, Duan; Du, Chaojun

2018-01-01

In recent years, the application of solar energy has been shown obvious advantages. Solar energy is being discontinuity and inhomogeneity, so energy storage technology becomes the key to the popularization and utilization of solar energy. Chemical storage is the most efficient way to store and transport solar energy. In the first and the second section of this paper, we discuss two aspects about the solar energy collector / reactor, and solar energy storage technology by hydrogen production, respectively. The third section describes the basic application of solar energy storage system, and proposes an association system by combining solar energy storage and power equipment. The fourth section briefly describes several research directions which need to be strengthened.
Exergy and exergoeconomic analysis of a Compressed Air Energy Storage combined with a district energy system

International Nuclear Information System (INIS)

Bagdanavicius, Audrius; Jenkins, Nick

2014-01-01

Highlights: • CAES and CAES with thermal storage systems were investigated. • The potential for using heat generated during the compression stage was analysed. • CAES-TS has the potential to be used both as energy storage and heat source. • CAES-TS could be a useful tool for balancing overall energy demand and supply. - Abstract: The potential for using heat generated during the compression stage of a Compressed Air Energy Storage system was investigated using exergy and exergoeconomic analysis. Two Compressed Air Energy Storage systems were analysed: Compressed Air Energy Storage (CAES) and Compressed Air Energy Storage combined with Thermal Storage (CAES-TS) connected to a district heating network. The maximum output of the CAES was 100 MWe and the output of the CAES-TS was 100 MWe and 105 MWth. The study shows that 308 GW h/year of electricity and 466 GW h/year of fuel are used to generate 375 GW h/year of electricity. During the compression of air 289 GW h/year of heat is generated, which is wasted in the CAES and used for district heating in the CAES-TS system. Energy efficiency of the CAES system was around 48% and the efficiency of CAES-TS was 86%. Exergoeconomic analysis shows that the exergy cost of electricity generated in the CAES was 13.89 ¢/kW h, and the exergy cost of electricity generated in the CAES-TS was 11.20 ¢/kW h. The exergy cost of heat was 22.24 ¢/kW h in the CAES-TS system. The study shows that CAES-TS has the potential to be used both as energy storage and heat source and could be a useful tool for balancing overall energy demand and supply
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)
Energy Storage System Control Algorithm by Operating Target Power to Improve Energy Sustainability of Smart Home

Directory of Open Access Journals (Sweden)

Byeongkwan Kang

2018-01-01

Full Text Available As energy issues are emerging around the world, a variety of smart home technologies aimed at realizing zero energy houses are being introduced. Energy storage system (ESS for smart home energy independence is increasingly gaining interest. However, limitations exist in that most of them are controlled according to time schedules or used in conjunction with photovoltaic (PV generation systems. In consideration of load usage patterns and PV generation of smart home, this study proposes an ESS control algorithm that uses constant energy of energy network while making maximum use of ESS. Constant energy means that the load consumes a certain amount of power under all conditions, which translates to low variability. The proposed algorithm makes a smart home a load of energy network with low uncertainty and complexity. The simulation results show that the optimal ESS operating target power not only makes the smart home use power constantly from the energy network, but also maximizes utilization of the ESS. In addition, since the smart home is a load that uses constant energy, it has the advantage of being able to operate an efficient energy network from the viewpoint of energy providers.
Optimal Stochastic Management of Distributed Energy Storage Embedded with Wind Farms

OpenAIRE

Yanchi, Xiao; Vargas, Bruce; Hamdi, Mohammd

2018-01-01

Increasing wind turbines (WT) penetration and low carbon demand can potentially lead to two different flow peaks, generation and load, within distribution networks. This will not only constrain WT penetration but also pose serious threats to network reliability. This paper proposes energy storage (ES) to reduce system congestion cost caused by the two peaks by sending cost-reflective economic signals to affect ES operation in responding to network conditions. Firstly, a new charging and disch...
Stationary super-capacitor energy storage system to save regenerative braking energy in a metro line

International Nuclear Information System (INIS)

Teymourfar, Reza; Asaei, Behzad; Iman-Eini, Hossein; Nejati fard, Razieh

2012-01-01

Highlights: ► Super-capacitors are used to store regenerative braking energy in a metro network. ► A novel approach is proposed to model easily and accurately the metro network. ► An efficient approach is proposed to calculate the required super-capacitors. ► Maximum energy saving is around 44% at off-peak period and 42% at peak period. ► Benefit/cost analyses are performed for the suggested ESS. - Abstract: In this paper, the stationary super-capacitors are used to store a metro network regenerative braking energy. In order to estimate the required energy storage systems (ESSs), line 3 of Tehran metro network is modeled through a novel approach, in peak and off-peak conditions based on the real data obtained from Tehran metro office. A useful method is proposed to predict the maximum instantaneous regenerative energy which is delivered to each station before applying ESS and based on that the ESS configuration for each station is determined. Finally, the effectiveness of the proposed ESS is confirmed by economic evaluations and benefit/cost analyses on line 3 of Tehran metro network.
Financial analysis of utility scale photovoltaic plants with battery energy storage

International Nuclear Information System (INIS)

Rudolf, Viktor; Papastergiou, Konstantinos D.

2013-01-01

Battery energy storage is a flexible and responsive form of storing electrical energy from Renewable generation. The need for energy storage mainly stems from the intermittent nature of solar and wind energy sources. System integrators are investigating ways to design plants that can provide more stable output power without compromising the financial performance that is vital for investors. Network operators on the other side set stringent requirements for the commissioning of new generation, including preferential terms for energy providers with a well-defined generation profile. The aim of this work is to highlight the market and technology drivers that impact the feasibility of battery energy storage in a Utility-scale solar PV project. A simulation tool combines a battery cycling and lifetime model with a solar generation profile and electricity market prices. The business cases of the present market conditions and a projected future scenario are analyzed. - Highlights: • Generation shifting with batteries allows PV projects to generate additional revenues. • Battery lifetime, lifecycles and price are less relevant than electricity market prices. • Installed battery capacity of up to 50% of the daily PV energy boosts project economy. • A 25% higher premium for energy storage could improve NPV by approximately 65%
Market potential of utility-purpose energy storage in Japan up to the year 2050

International Nuclear Information System (INIS)

Tanaka, T.; Kurihara, I.

1998-01-01

The market potential of future energy storage in power network systems in Japan is estimated by using the linear programming method under two main scenarios for the years 2030 and 2050. One is a base scenario in which the power demand and associated performances are simply extrapolated from the present to the future year of interest. The other is a modified scenario under which they are influenced by foreseeable changes in social structure and introduction of demand-side energy storage. This estimation indicates that the optimum capacity of energy storage will be about 10 to 15% of the total generation capacity. (author)
Performance analysis of an integrated energy storage and energy upgrade thermochemical solid–gas sorption system for seasonal storage of solar thermal energy

International Nuclear Information System (INIS)

Li, Tingxian; Wang, Ruzhu; Kiplagat, Jeremiah K.; Kang, YongTae

2013-01-01

An innovative dual-mode thermochemical sorption energy storage method is proposed for seasonal storage of solar thermal energy with little heat losses. During the charging phase in summer, solar thermal energy is stored in form of chemical bonds resulting from thermochemical decomposition process, which enables the stored energy to be kept several months at ambient temperature. During the discharging phase in winter, the stored thermal energy is released in the form of chemical reaction heat resulting from thermochemical synthesis process. Thermodynamic analysis showed that the advanced dual-mode thermochemical sorption energy storage is an effective method for the long-term seasonal storage of solar energy. A coefficient of performance (COP h ) of 0.6 and energy density higher than 1000 kJ/kg of salt can be attained from the proposed system. During the discharging phase at low ambient temperatures, the stored thermal energy can be upgraded by use of a solid–gas thermochemical sorption heat transformer cycle. The proposed thermochemical sorption energy storage has distinct advantages over the conventional sensible heat and latent heat storage, such as higher energy storage density, little heat losses, integrated energy storage and energy upgrade, and thus it can contribute to improve the seasonal utilization of solar thermal energy. - Highlights: ► A dual-mode solid thermochemical sorption is proposed for seasonal solar thermal energy storage. ► Energy upgrade techniques into the energy storage system are integrated. ► Performance of the proposed seasonal energy storage system is evaluated. ► Energy density and COP h from the proposed system are as high as 1043 kJ/kg of salt and 0.60, respectively
Energy Storage Systems

Science.gov (United States)

Elliott, David

2017-07-01

As renewable energy use expands there will be a need to develop ways to balance its variability. Storage is one of the options. Presently the main emphasis is for systems storing electrical power in advanced batteries (many of them derivatives of parallel developments in the electric vehicle field), as well as via liquid air storage, compressed air storage, super-capacitors and flywheels, and, the leader so far, pumped hydro reservoirs. In addition, new systems are emerging for hydrogen generation and storage, feeding fuel cell power production. Heat (and cold) is also a storage medium and some systems exploit thermal effects as part of wider energy management activity. Some of the more exotic ones even try to use gravity on a large scale. This short book looks at all the options, their potentials and their limits. There are no clear winners, with some being suited to short-term balancing and others to longer-term storage. The eventual mix adopted will be shaped by the pattern of development of other balancing measures, including smart-grid demand management and super-grid imports and exports.
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
Operation and sizing of energy storage for wind power plants in a market system

International Nuclear Information System (INIS)

Korpaas, M.; Holen, A.T.

2003-01-01

This paper presents a method for the scheduling and operation of energy storage for wind power plants in electricity markets. A dynamic programming algorithm is employed to determine the optimal energy exchange with the market for a specified scheduling period, taking into account transmission constraints. During operation, the energy storage is used to smooth variations in wind power production in order to follow the scheduling plan. The method is suitable for any type of energy storage and is also useful for other intermittent energy resources than wind. An application of the method to a case study is also presented, where the impact of energy storage sizing and wind forecasting accuracy on system operation and economics are emphasized. Simulation results show that energy storage makes it possible for owners of wind power plants to take advantage of variations in the spot price, by thus increasing the value of wind power in electricity markets. With present price estimates, energy storage devices such as reversible fuel cells are likely to be a more expensive alternative than grid expansions for the siting of wind farms in weak networks. However, for areas where grid expansions lead to unwanted interference with the local environment, energy storage should be considered as a reasonable way to increase the penetration of wind power. (author)
Localization of Energy Harvesting Empowered Underwater Optical Wireless Sensor Networks

KAUST Repository

Saeed, Nasir; Celik, Abdulkadir; Al-Naffouri, Tareq Y.; Alouini, Mohamed-Slim

2017-01-01

with insufficient battery, harvest the energy and starts communicating once it has sufficient energy storage. Network localization is carried out by measuring the RSSs of active nodes, which are modeled based on the underwater optical communication channel
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).
Graphene-Based Integrated Photovoltaic Energy Harvesting/Storage Device.

Science.gov (United States)

Chien, Chih-Tao; Hiralal, Pritesh; Wang, Di-Yan; Huang, I-Sheng; Chen, Chia-Chun; Chen, Chun-Wei; Amaratunga, Gehan A J

2015-06-24

Energy scavenging has become a fundamental part of ubiquitous sensor networks. Of all the scavenging technologies, solar has the highest power density available. However, the energy source is erratic. Integrating energy conversion and storage devices is a viable route to obtain self-powered electronic systems which have long-term maintenance-free operation. In this work, we demonstrate an integrated-power-sheet, consisting of a string of series connected organic photovoltaic cells (OPCs) and graphene supercapacitors on a single substrate, using graphene as a common platform. This results in lighter and more flexible power packs. Graphene is used in different forms and qualities for different functions. Chemical vapor deposition grown high quality graphene is used as a transparent conductor, while solution exfoliated graphene pastes are used as supercapacitor electrodes. Solution-based coating techniques are used to deposit the separate components onto a single substrate, making the process compatible with roll-to-roll manufacture. Eight series connected OPCs based on poly(3-hexylthiophene)(P3HT):phenyl-C61-butyric acid methyl ester (PC60 BM) bulk-heterojunction cells with aluminum electrodes, resulting in a ≈5 V open-circuit voltage, provide the energy harvesting capability. Supercapacitors based on graphene ink with ≈2.5 mF cm(-2) capacitance provide the energy storage capability. The integrated-power-sheet with photovoltaic (PV) energy harvesting and storage functions had a mass of 0.35 g plus the substrate. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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.
Erasure Coded Storage on a Changing Network

DEFF Research Database (Denmark)

Sipos, Marton A.; Venkat, Narayan; Oran, David

2016-01-01

As faster storage devices become commercially viable alternatives to disk drives, the network is increasingly becoming the bottleneck in achieving good performance in distributed storage systems. This is especially true for erasure coded storage, where the reconstruction of lost data can signific...
Molecular solar thermal energy storage in photoswitch oligomers increases energy densities and storage times.

Science.gov (United States)

Mansø, Mads; Petersen, Anne Ugleholdt; Wang, Zhihang; Erhart, Paul; Nielsen, Mogens Brøndsted; Moth-Poulsen, Kasper

2018-05-16

Molecular photoswitches can be used for solar thermal energy storage by photoisomerization into high-energy, meta-stable isomers; we present a molecular design strategy leading to photoswitches with high energy densities and long storage times. High measured energy densities of up to 559 kJ kg -1 (155 Wh kg -1 ), long storage lifetimes up to 48.5 days, and high quantum yields of conversion of up to 94% per subunit are demonstrated in norbornadiene/quadricyclane (NBD/QC) photo-/thermoswitch couples incorporated into dimeric and trimeric structures. By changing the linker unit between the NBD units, we can at the same time fine-tune light-harvesting and energy densities of the dimers and trimers so that they exceed those of their monomeric analogs. These new oligomers thereby meet several of the criteria to be met for an optimum molecule to ultimately enter actual devices being able to undergo closed cycles of solar light-harvesting, energy storage, and heat release.
Energy storage. Technologies and potentials to compensate supply and demand; Energiespeicherung. Technologien und Potentiale zum Ausgleich von Angebot und Nachfrage

Energy Technology Data Exchange (ETDEWEB)

Kruhl, Joerg [E.ON New Build and Technology, Gelsenkirchen (Germany); Doll, Markus [RWE Power AG, Essen (Germany)

2011-07-01

Future energy systems will be based on a high proportion of renewable and fluctuating power generation. This will result in system states in which the merging of supply and demand represents a significant challenge. Energy storages are a measure to overcome this challenge. However, energy storages are not the sole solution. So there exist alternative measures such as network expansion and load management as a cost-effective solutions. Energy storages as an important building block for future energy systems must be a function of other measures such as network expansion and demand management designed specifically. This includes a financial support for technical development and also the attendance of the launch by means of appropriate economic incentives.
A Review of Energy Storage Technologies

DEFF Research Database (Denmark)

Connolly, David

2010-01-01

A brief examination into the energy storage techniques currently available for the integration of fluctuating renewable energy was carried out. These included Pumped Hydroelectric Energy Storage (PHES), Underground Pumped Hydroelectric Energy Storage (UPHES), Compressed Air Energy Storage (CAES...... than PHES depending on the availability of suitable sites. FBES could also be utilised in the future for the integration of wind, but it may not have the scale required to exist along with electric vehicles. The remaining technologies will most likely be used for their current applications...

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).
A Review of Flywheel Energy Storage System Technologies and Their Applications

Directory of Open Access Journals (Sweden)

Mustafa E. Amiryar

2017-03-01

Full Text Available Energy storage systems (ESS provide a means for improving the efficiency of electrical systems when there are imbalances between supply and demand. Additionally, they are a key element for improving the stability and quality of electrical networks. They add flexibility into the electrical system by mitigating the supply intermittency, recently made worse by an increased penetration of renewable generation. One energy storage technology now arousing great interest is the flywheel energy storage systems (FESS, since this technology can offer many advantages as an energy storage solution over the alternatives. Flywheels have attributes of a high cycle life, long operational life, high round-trip efficiency, high power density, low environmental impact, and can store megajoule (MJ levels of energy with no upper limit when configured in banks. This paper presents a critical review of FESS in regards to its main components and applications, an approach not captured in earlier reviews. Additionally, earlier reviews do not include the most recent literature in this fast-moving field. A description of the flywheel structure and its main components is provided, and different types of electric machines, power electronics converter topologies, and bearing systems for use in flywheel storage systems are discussed. The main applications of FESS are explained and commercially available flywheel prototypes for each application are described. The paper concludes with recommendations for future research.
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.
Energy storage in Canada - Embassy report

International Nuclear Information System (INIS)

Quennehen, Sylvain

2014-09-01

After having outlined what is at stake in energy storage in the world (brief presentation of storage methods, overview of world electricity production and its storage challenges), and given an overview of the Canadian energy sector, this report gives an overview of the Canadian key and particularly innovating actors: main organisations, scientific research (in the fields of advanced batteries, of fuel cells, and of thermal storage), industrial sector (leaders in electricity production, in the electric or hybrid automotive sector and in the field of portable electronic devices, in the Li-ion battery sector, and in the hydrogen fuel cell sector, innovating actors in other energy storage methods). The author then discusses the innovation momentum in Canada: examples of energy storage projects by public organisations (CNRC, RNC), industrial projects in energy projects, investment dynamics
Storage capacity and retrieval time of small-world neural networks

International Nuclear Information System (INIS)

Oshima, Hiraku; Odagaki, Takashi

2007-01-01

To understand the influence of structure on the function of neural networks, we study the storage capacity and the retrieval time of Hopfield-type neural networks for four network structures: regular, small world, random networks generated by the Watts-Strogatz (WS) model, and the same network as the neural network of the nematode Caenorhabditis elegans. Using computer simulations, we find that (1) as the randomness of network is increased, its storage capacity is enhanced; (2) the retrieval time of WS networks does not depend on the network structure, but the retrieval time of C. elegans's neural network is longer than that of WS networks; (3) the storage capacity of the C. elegans network is smaller than that of networks generated by the WS model, though the neural network of C. elegans is considered to be a small-world network
Multielectron-Transfer-based Rechargeable Energy Storage of Two-Dimensional Coordination Frameworks with Non-Innocent Ligands.

Science.gov (United States)

Wada, Keisuke; Sakaushi, Ken; Sasaki, Sono; Nishihara, Hiroshi

2018-04-19

The metallically conductive bis(diimino)nickel framework (NiDI), an emerging class of metal-organic framework (MOF) analogues consisting of two-dimensional (2D) coordination networks, was found to have an energy storage principle that uses both cation and anion insertion. This principle gives high energy led by a multielectron transfer reaction: Its specific capacity is one of the highest among MOF-based cathode materials in rechargeable energy storage devices, with stable cycling performance up to 300 cycles. This mechanism was studied by a wide spectrum of electrochemical techniques combined with density-functional calculations. This work shows that a rationally designed material system of conductive 2D coordination networks can be promising electrode materials for many types of energy devices. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Battery energy storage market feasibility study

International Nuclear Information System (INIS)

Kraft, S.; Akhil, A.

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)
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.
Operating Wireless Sensor Nodes without Energy Storage: Experimental Results with Transient Computing

Directory of Open Access Journals (Sweden)

Faisal Ahmed

2016-12-01

Full Text Available Energy harvesting is increasingly used for powering wireless sensor network nodes. Recently, it has been suggested to combine it with the concept of transient computing whereby the wireless sensor nodes operate without energy storage capabilities. This new combined approach brings benefits, for instance ultra-low power nodes and reduced maintenance, but also raises new challenges, foremost dealing with nodes that may be left without power for various time periods. Although transient computing has been demonstrated on microcontrollers, reports on experiments with wireless sensor nodes are still scarce in the literature. In this paper, we describe our experiments with solar, thermal, and RF energy harvesting sources that are used to power sensor nodes (including wireless ones without energy storage, but with transient computing capabilities. The results show that the selected solar and thermal energy sources can operate both the wired and wireless nodes without energy storage, whereas in our specific implementation, the developed RF energy source can only be used for the selected nodes without wireless connectivity.
Design and thermodynamic analysis of a hybrid energy storage system based on A-CAES (adiabatic compressed air energy storage) and FESS (flywheel energy storage system) for wind power application

International Nuclear Information System (INIS)

Zhao, Pan; Dai, Yiping; Wang, Jiangfeng

2014-01-01

Electricity generated from renewable wind sources is highly erratic due to the intermittent nature of wind. This uncertainty of wind power can lead to challenges regarding power system operation and dispatch. Energy storage system in conjunction with wind energy system can offset these effects, making the wind power controllable. Moreover, the power spectrum of wind power exhibits that the fluctuations of wind power include various components with different frequencies and amplitudes. Thus, the hybrid energy storage system is more suitable for smoothing out the wind power fluctuations effectively rather than the independent energy storage system. A hybrid energy storage system consisting of adiabatic compressed air energy storage (A-CAES) system and flywheel energy storage system (FESS) is proposed for wind energy application. The design of the proposed system is laid out firstly. The A-CAES system operates in variable cavern pressure, constant turbine inlet pressure mode, whereas the FESS is controlled by constant power strategy. Then, the off-design analysis of the proposed system is carried out. Meanwhile, a parametric analysis is also performed to investigate the effects of several parameters on the system performance, including the ambient conditions, inlet temperature of compressor, storage cavern temperature, maximum and minimum pressures of storage cavern. - Highlights: • A wind-hybrid energy storage system composed of A-CAES and FESS is proposed. • The design of the proposed hybrid energy storage system is laid out. • The off-design analysis of the proposed system is carried out. • A parametric analysis is conducted to examine the system performance
Lessons Learned from the Puerto Rico Battery Energy Storage System

Energy Technology Data Exchange (ETDEWEB)

Boyes, John D.; De Anda, Mindi Farber; Torres, Wenceslao

1999-08-11

The Puerto Rico Electric Power Authority (PREPA) installed a 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 Puerto Rico facility is presently the largest operating battery storage system in the world and has successfully provided frequency control, voltage regulation, and spinning reseme 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. However, the facility has suffered accelerated cell failures in the past year and PREPA is committed to restoring the plant to full capacity. This represents the first repowering of a large utility battery facility. PREPA and its vendors and contractors learned many valuable lessons during all phases of project development and operation, which are summarized in this paper.
Design of Energy Storage Management System Based on FPGA in Micro-Grid

Science.gov (United States)

Liang, Yafeng; Wang, Yanping; Han, Dexiao

2018-01-01

Energy storage system is the core to maintain the stable operation of smart micro-grid. Aiming at the existing problems of the energy storage management system in the micro-grid such as Low fault tolerance, easy to cause fluctuations in micro-grid, a new intelligent battery management system based on field programmable gate array is proposed : taking advantage of FPGA to combine the battery management system with the intelligent micro-grid control strategy. Finally, aiming at the problem that during estimation of battery charge State by neural network, initialization of weights and thresholds are not accurate leading to large errors in prediction results, the genetic algorithm is proposed to optimize the neural network method, and the experimental simulation is carried out. The experimental results show that the algorithm has high precision and provides guarantee for the stable operation of micro-grid.
Energy Storage Publications | Transportation Research | NREL

Science.gov (United States)

, California. 23 pp.; NREL Report No. PR-5400-60290. Optimal Sizing of Energy Storage and Photovoltaic Power (11) 2017 pp. 1095-1118. Life Prediction Model for Grid-Connected Li-ion Battery Energy Storage System Prediction Model for Grid-Connected Li-ion Battery Energy Storage System - Preprint Paper Source: Smith
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
Heat pipe based cold energy storage systems for datacenter energy conservation

International Nuclear Information System (INIS)

Singh, Randeep; Mochizuki, Masataka; Mashiko, Koichi; Nguyen, Thang

2011-01-01

In the present paper, design and economics of the novel type of thermal control system for datacenter using heat pipe based cold energy storage has been proposed and discussed. Two types of cold energy storage system namely: ice storage system and cold water storage system are explained and sized for datacenter with heat output capacity of 8800 kW. Basically, the cold energy storage will help to reduce the chiller running time that will save electricity related cost and decrease greenhouse gas emissions resulting from the electricity generation from non-renewable sources. The proposed cold energy storage system can be retrofit or connected in the existing datacenter facilities without major design changes. Out of the two proposed systems, ice based cold energy storage system is mainly recommended for datacenters which are located in very cold locations and therefore can offer long term seasonal storage of cold energy within reasonable cost. One of the potential application domains for ice based cold energy storage system using heat pipes is the emergency backup system for datacenter. Water based cold energy storage system provides more compact size with short term storage (hours to days) and is potential for datacenters located in areas with yearly average temperature below the permissible cooling water temperature (∼25 o C). The aforesaid cold energy storage systems were sized on the basis of metrological conditions in Poughkeepsie, New York. As an outcome of the thermal and cost analysis, water based cold energy storage system with cooling capability to handle 60% of datacenter yearly heat load will provide an optimum system size with minimum payback period of 3.5 years. Water based cold energy storage system using heat pipes can be essentially used as precooler for chiller. Preliminary results obtained from the experimental system to test the capability of heat pipe based cold energy storage system have provided satisfactory outcomes and validated the proposed
A Comprehensive Review of Thermal Energy Storage

Directory of Open Access Journals (Sweden)

Ioan Sarbu

2018-01-01

Full Text Available Thermal energy storage (TES is a technology that stocks thermal energy by heating or cooling a storage medium so that the stored energy can be used at a later time for heating and cooling applications and power generation. TES systems are used particularly in buildings and in industrial processes. This paper is focused on TES technologies that provide a way of valorizing solar heat and reducing the energy demand of buildings. The principles of several energy storage methods and calculation of storage capacities are described. Sensible heat storage technologies, including water tank, underground, and packed-bed storage methods, are briefly reviewed. Additionally, latent-heat storage systems associated with phase-change materials for use in solar heating/cooling of buildings, solar water heating, heat-pump systems, and concentrating solar power plants as well as thermo-chemical storage are discussed. Finally, cool thermal energy storage is also briefly reviewed and outstanding information on the performance and costs of TES systems are included.
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.
Microsupercapacitors as miniaturized energy-storage components for on-chip electronics

Science.gov (United States)

Kyeremateng, Nana Amponsah; Brousse, Thierry; Pech, David

2017-01-01

The push towards miniaturized electronics calls for the development of miniaturized energy-storage components that can enable sustained, autonomous operation of electronic devices for applications such as wearable gadgets and wireless sensor networks. Microsupercapacitors have been targeted as a viable route for this purpose, because, though storing less energy than microbatteries, they can be charged and discharged much more rapidly and have an almost unlimited lifetime. In this Review, we discuss the progress and the prospects of integrated miniaturized supercapacitors. In particular, we discuss their power performances and emphasize the need of a three-dimensional design to boost their energy-storage capacity. This is obtainable, for example, through self-supported nanostructured electrodes. We also critically evaluate the performance metrics currently used in the literature to characterize microsupercapacitors and offer general guidelines to benchmark performances towards prospective applications.
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.
Solar Energy Grid Integration Systems -- Energy Storage (SEGIS-ES).

Energy Technology Data Exchange (ETDEWEB)

Hanley, Charles J.; Ton, Dan T. (U.S. Department of Energy, Washington, D.C.); Boyes, John D.; Peek, Georgianne Huff

2008-07-01

This paper describes the concept for augmenting the SEGIS Program (an industry-led effort to greatly enhance the utility of distributed PV systems) with energy storage in residential and small commercial applications (SEGIS-ES). The goal of SEGIS-ES is to develop electrical energy storage components and systems specifically designed and optimized for grid-tied PV applications. This report describes the scope of the proposed SEGIS-ES Program and why it will be necessary to integrate energy storage with PV systems as PV-generated energy becomes more prevalent on the nation's utility grid. It also discusses the applications for which energy storage is most suited and for which it will provide the greatest economic and operational benefits to customers and utilities. Included is a detailed summary of the various storage technologies available, comparisons of their relative costs and development status, and a summary of key R&D needs for PV-storage systems. The report concludes with highlights of areas where further PV-specific R&D is needed and offers recommendations about how to proceed with their development.

Hybrid Swarm Intelligence Optimization Approach for Optimal Data Storage Position Identification in Wireless Sensor Networks

Science.gov (United States)

Mohanasundaram, Ranganathan; Periasamy, Pappampalayam Sanmugam

2015-01-01

The current high profile debate with regard to data storage and its growth have become strategic task in the world of networking. It mainly depends on the sensor nodes called producers, base stations, and also the consumers (users and sensor nodes) to retrieve and use the data. The main concern dealt here is to find an optimal data storage position in wireless sensor networks. The works that have been carried out earlier did not utilize swarm intelligence based optimization approaches to find the optimal data storage positions. To achieve this goal, an efficient swam intelligence approach is used to choose suitable positions for a storage node. Thus, hybrid particle swarm optimization algorithm has been used to find the suitable positions for storage nodes while the total energy cost of data transmission is minimized. Clustering-based distributed data storage is utilized to solve clustering problem using fuzzy-C-means algorithm. This research work also considers the data rates and locations of multiple producers and consumers to find optimal data storage positions. The algorithm is implemented in a network simulator and the experimental results show that the proposed clustering and swarm intelligence based ODS strategy is more effective than the earlier approaches. PMID:25734182
Energy Storage Applications in Power Systems with Renewable Energy Generation

Science.gov (United States)

Ghofrani, Mahmoud

demonstrate our operational-planning framework and economic justification for different storage applications. A new reliability model is proposed for security and adequacy assessment of power networks containing renewable resources and energy storage systems. The proposed model is used in combination with the operational-planning framework to enhance the reliability and operability of wind integration. The proposed framework optimally utilizes the storage capacity for reliability applications of wind integration. This is essential for justification of storage deployment within regulated utilities where the absence of market opportunities limits the economic advantage of storage technologies over gas-fired generators. A control strategy is also proposed to achieve the maximum reliability using energy storage systems. A cost-benefit analysis compares storage technologies and conventional alternatives to reliably and efficiently integrate different wind penetrations and determines the most economical design. Our simulation results demonstrate the necessity of optimal storage placement for different wind applications. This dissertation also proposes a new stochastic framework to optimally charge and discharge electric vehicles (EVs) to mitigate the effects of wind power uncertainties. Vehicle-to-grid (V2G) service for hedging against wind power imbalances is introduced as a novel application for EVs. This application enhances the predictability of wind power and reduces the power imbalances between the scheduled output and actual power. An Auto Regressive Moving Average (ARMA) wind speed model is developed to forecast the wind power output. Driving patterns of EVs are stochastically modeled and the EVs are clustered in the fleets of similar daily driving patterns. Monte Carlo Simulation (MCS) simulates the system behavior by generating samples of system states using the wind ARMA model and EVs driving patterns. A Genetic Algorithm (GA) is used in combination with MCS to optimally
Study of Aquifer Thermal Energy Storage

Science.gov (United States)

Okuyama, Masaaki; Umemiya, Hiromichi; Shibuya, Ikuko; Haga, Eiji

Yamagata University 'Aquifer Thermal Energy Storage (ATES)' is the experimental system which has been running since 1982. From the results for along terms of experiments, we obtain many important knowledge. This paper presents the accomplishments for 16 years and the characteristics of thermal energy storage in thermal energy storage well. The conclusions show as follows. 1)In recent years, the thermal recovery factor of warm energy storage well becomes almost constant at about 60%. 2) The thermal recovery factor of cool energy storage well increases gradually and becomes at about 15%. 3) Since the ferric colloidal dam is formed in aquifer, thermal recovery factor increase year after year. 4) Back wash can remove clogging for ferric colloidal dam. 5) The apparent thermal diffusivity decrease gradually due to ferric colloidal dam.
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.
A transeuropean project ICOP-DISS-2140 dealing with the use of energy storage in power systems

International Nuclear Information System (INIS)

Feser, K.; Hadjsaid, N.; Herlander, K.; Nazarko, J.; Prochovnik, A.; Stroev, V.; Styczynski, Z.; Vale, A.; Voropai, N.

1998-01-01

In the early 90s economic crisis led to the reduction of electric power and energy consumption growth in the West. The political transformation in the East caused significant evolution of the power system structures (e.g. deregulation). Changes of dynamic and static conditions in the electric power systems have been observed. In the last 5-6 years an unexpected low load growth complicated optimal expansion planning for distribution and transmission networks in power systems. Besides intelligent planning, a delay of a necessary network investment (e.g. cable lines) using some distributed small size storage can be obtained. In this way the risk of wrong investments can be minimised. In the East, using energy storage can also provide additional assistance by improving the quality of energy in distribution systems. For two years, the European Community sponsored an international project ''Intelligent Computation and Simulation in Planning and Operation of Power System taking into Account Energy Storage'', in the scope of the INCO-Copernicus program. Eight partners from six countries (Germany - coordination, Russia, Ukraine, Poland, France and Portugal) took as a goal to use ''synergy effects'' by developing a common base for a future battery storage demonstration facility. (author)
Numerical investigation of a joint approach to thermal energy storage and compressed air energy storage in aquifers

International Nuclear Information System (INIS)

Guo, Chaobin; Zhang, Keni; Pan, Lehua; Cai, Zuansi; Li, Cai; Li, Yi

2017-01-01

Highlights: •One wellbore-reservoir numerical model was built to study the impact of ATES on CAESA. •With high injection temperature, the joint of ATES can improve CAESA performance. •The considerable utilization of geothermal occurs only at the beginning of operations. •Combination of CAESA and ATES can be achieved in common aquifers. -- Abstract: Different from conventional compressed air energy storage (CAES) systems, the advanced adiabatic compressed air energy storage (AA-CAES) system can store the compression heat which can be used to reheat air during the electricity generation stage. Thus, AA-CAES system can achieve a higher energy storage efficiency. Similar to the AA-CAES system, a compressed air energy storage in aquifers (CAESA) system, which is integrated with an aquifer thermal energy storage (ATES) could possibly achieve the same objective. In order to investigate the impact of ATES on the performance of CAESA, different injection air temperature schemes are designed and analyzed by using numerical simulations. Key parameters relative to energy recovery efficiencies of the different injection schemes, such as pressure distribution and temperature variation within the aquifers as well as energy flow rate in the injection well, are also investigated in this study. The simulations show that, although different injection schemes have a similar overall energy recovery efficiency (∼97%) as well as a thermal energy recovery efficiency (∼79.2%), the higher injection air temperature has a higher energy storage capability. Our results show the total energy storage for the injection air temperature at 80 °C is about 10% greater than the base model scheme at 40 °C. Sensitivity analysis reveal that permeability of the reservoir boundary could have significant impact on the system performance. However, other hydrodynamic and thermodynamic properties, such as the storage reservoir permeability, thermal conductivity, rock grain specific heat and rock
Photovoltaic power systems energy storage

International Nuclear Information System (INIS)

Buldini, P.L.

1991-01-01

Basically, the solar photovoltaic power system consists of: Array of solar panels; Charge/voltage stabilizer; Blocking diode and Storage device. The storage device is a very important part of the system due to the necessity to harmonize the inevitable time shift between energy supply and demand. As energy storage, different devices can be utilized, such as hydropumping, air or other gas compression, flywheel, superconducting magnet, hydrogen generation and so on, but actually secondary (rechargeable) electrochemical cells appear to be the best storage device, due to the direct use for recharge of the d.c. current provided by the solar panels, without any intermediate step of energy transformation and its consequent loss of efficiency
Hybrid Hydro Renewable Energy Storage Model

Science.gov (United States)

Dey, Asit Kr

2018-01-01

This paper aims at presenting wind & tidal turbine pumped-storage solutions for improving the energy efficiency and economic sustainability of renewable energy systems. Indicated a viable option to solve problems of energy production, as well as in the integration of intermittent renewable energies, providing system flexibility due to energy load’s fluctuation, as long as the storage of energy from intermittent sources. Sea water storage energy is one of the best and most efficient options in terms of renewable resources as an integrated solution allowing the improvement of the energy system elasticity and the global system efficiency.
High Tc superconducting energy storage systems

Energy Technology Data Exchange (ETDEWEB)

Werfel, Frank [Adelwitz Technologiezentrum GmbH (ATZ), Arzberg-Adelwitz (Germany)

2012-07-01

Electric energy is basic to heat and light our homes, to power our businesses and to transport people and goods. Powerful storage techniques like SMES, Flywheel, Super Capacitor, and Redox - Flow batteries are needed to increase the overall efficiency, stability and quality of electrical grids. High-Tc superconductors (HTS) possess superior physical and technical properties and can contribute in reducing the dissipation and losses in electric machines as motors and generators, in electric grids and transportation. The renewable energy sources as solar, wind energy and biomass will require energy storage systems even more as a key technology. We survey the physics and the technology status of superconducting flywheel energy storage (FESS) and magnetic energy storage systems (SMES) for their potential of large-scale commercialization. We report about a 10 kWh / 250 kW flywheel with magnetic stabilization of the rotor. The progress of HTS conductor science and technological engineering are basic for larger SMES developments. The performance of superconducting storage systems is reviewed and compared. We conclude that a broad range of intensive research and development in energy storage is urgently needed to produce technological options that can allow both climate stabilization and economic development.
Distributed generation, storage, demand response and energy efficiency as alternatives to grid capacity enhancement

International Nuclear Information System (INIS)

Poudineh, Rahmatallah; Jamasb, Tooraj

2014-01-01

The need for investment in capital intensive electricity networks is on the rise in many countries. A major advantage of distributed resources is their potential for deferring investments in distribution network capacity. However, utilizing the full benefits of these resources requires addressing several technical, economic and regulatory challenges. A significant barrier pertains to the lack of an efficient market mechanism that enables this concept and also is consistent with business model of distribution companies under an unbundled power sector paradigm. This paper proposes a market-oriented approach termed as “contract for deferral scheme” (CDS). The scheme outlines how an economically efficient portfolio of distributed generation, storage, demand response and energy efficiency can be integrated as network resources to reduce the need for grid capacity and defer demand driven network investments. - Highlights: • The paper explores a practical framework for smart electricity distribution grids. • The aim is to defer large capital investments in the network by utilizing and incentivising distributed generation, demand response, energy efficiency and storage as network resources. • The paper discusses a possible new market model that enables integration of distributed resources as alternative to grid capacity enhancement
Conflict free network coding for distributed storage networks

KAUST Repository

Al-Habob, Ahmed A.; Sorour, Sameh; Aboutorab, Neda; Sadeghi, Parastoo

2015-01-01

© 2015 IEEE. In this paper, we design a conflict free instantly decodable network coding (IDNC) solution for file download from distributed storage servers. Considering previously downloaded files at the clients from these servers as side
Robust multi-objective control of hybrid renewable microgeneration systems with energy storage

International Nuclear Information System (INIS)

Allison, John

2017-01-01

Highlights: • A hybrid energy system of micro-CHP, solar PV, and battery storage is presented. • Possible to exploit synergy of systems to fulfil the thermal and electrical demands. • Can control to minimise the interaction with the local electrical network. • Three different control approaches were compared. • The nonlinear inversion-based control strategy exhibits optimum performance. - Abstract: Microgeneration technologies are positioned to address future building energy efficiency requirements and facilitate the integration of renewables into buildings to ensure a sustainable, energy-secure future. This paper explores the development of a robust multi-input multi-output (MIMO) controller applicable to the control of hybrid renewable microgeneration systems with the objective of minimising the electrical grid utilisation of a building while fulfilling the thermal demands. The controller employs the inverse dynamics of the building, servicing systems, and energy storage with a robust control methodology. These inverse dynamics provides the control system with knowledge of the complex cause and effect relationships between the system, the controlled inputs, and the external disturbances, while an outer-loop control ensures robust, stable control in the presence of modelling deficiencies/uncertainty and unknown disturbances. Variable structure control compensates for the physical limitations of the systems whereby the control strategy employed switches depending on the current utilisation and availability of the energy supplies. Preliminary results presented for a system consisting of a micro-CHP unit, solar PV, and battery storage indicate that the control strategy is effective in minimising the interaction with the local electrical network and maximising the utilisation of the available renewable energy.
The vision of a future energy supply network

International Nuclear Information System (INIS)

Koeppel, G.; Favre-Perrod, P.; Geidl, M.; Kloeckl, B.

2005-01-01

This article discusses a concept developed within the framework of a project entitled 'Vision of Future Energy Networks' carried out at the Swiss Federal Institute of Technology in Zurich. The project looked at the possibility of using synergies between various energy carriers and systems. Network topologies are discussed that can cope with the distributed production of energy in installations featuring technologies such as combined heat and power, micro gas turbines and wind-power installations. The topics discussed include the use of a large amount of such distributed generation capacity and which network topologies and storage requirements would be necessary for their operation. Also, under the title 'energy hubs', possible synergies with other forms of energy use are examined. The modelling, dimensioning and use of such hubs are dealt with for various scenarios, ranging from single family homes through to combinations of industrial complexes and whole residential areas. Questions of reliability are addressed and the idea of an 'Energy Interconnector' that supplies electrical, chemical and thermal energy is introduced
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....
Research on the Orientation and Application of Distributed Energy Storage in Energy Internet

Science.gov (United States)

Zeng, Ming; Zhou, Pengcheng; Li, Ran; Zhou, Jingjing; Chen, Tao; Li, Zhe

2018-01-01

Energy storage is indispensable resources to achieve a high proportion of new energy power consumption in electric power system. As an important support to energy Internet, energy storage system can achieve a variety of energy integration operation to ensure maximum energy efficiency. In this paper, firstly, the SWOT analysis method is used to express the internal and external advantages and disadvantages of distributed energy storage participating in the energy Internet. Secondly, the function orientation of distributed energy storage in energy Internet is studied, based on which the application modes of distributed energy storage in virtual power plant, community energy storage and auxiliary services are deeply studied. Finally, this paper puts forward the development strategy of distributed energy storage which is suitable for the development of China’s energy Internet, and summarizes and prospects the application of distributed energy storage system.
Storage of energies - Translating potential into actions

International Nuclear Information System (INIS)

Signoret, Stephane; Mary, Olivier; Petitot, Pauline; Dejeu, Mathieu; De Santis, Audrey

2015-01-01

In this set of articles, a first one evokes issues discussed during a colloquium held in Paris by the European association for storage of energy, the possibilities mentioned about energy storage development in the French bill project for energy transition, and the importance of non-interconnected areas in the development of energy storage. A second article proposes an overview of developments and advances in energy storage in California which adopted suitable laws. The German situation is then briefly described: needs are still to be defined and a road map has been published in 2014, as technologies are expensive and the legal framework is still complex. The next article outlines the conditions of development of the power-to-gas sector (as a process of valorisation of excess electricity). An article gives an overview of technological developments in the field of electrochemical energy storage (batteries). The results of the PEPS study (a study on the potential of energy storage) in Europe are commented. An interview with a member of the French BRGM (Bureau of Mines) outlines the major role which underground storage could play in energy transition. The Seti project for an intelligent thermal energy storage and a better use of renewable energies is then presented. An article comments how to use foodstuff cold to make consumption cut-offs. A last article comments how superconductors could be used in the future for batteries. Few examples are briefly presented: a molten salt-based storage by Areva, a local production of green hydrogen in France, an innovating project of solar energy storage in Switzerland, and the Toucan solar plant in French Guyana
Modeling and Control of Heat Networks With Storage : The Single-Producer Multiple-Consumer Case

NARCIS (Netherlands)

Scholten, Tjardo; De Persis, Claudio; Tesi, Pietro

In heat networks, energy storage in the form of hot water in a tank is a viable approach to balancing supply and demand. In order to store a desired amount of energy, both the volume and temperature of the water in the tank need to converge to desired setpoints. To this end, we provide a provably
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.
Superconducting magnetic energy storage

International Nuclear Information System (INIS)

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
Electricity storage - A challenge for energy transition

International Nuclear Information System (INIS)

Bart, Jean-Baptiste; Nekrasov, Andre; Pastor, Emmanuel; Benefice, Emmanuel; Brincourt, Thierry; Cagnac, Albannie; Brisse, Annabelle; Jeandel, Elodie; Lefebvre, Thierry; Penneau, Jean-Francois; Radvanyi, Etienne; Delille, Gautier; Hinchliffe, Timothee; Lancel, Gilles; Loevenbruck, Philippe; Soler, Robert; Stevens, Philippe; Torcheux, Laurent

2017-01-01

After a presentation of the energetic context and of its issues, this collective publication proposes presentations of various electricity storage technologies with a distinction between direct storage, thermal storage and hydrogen storage. As far as direct storage is concerned, the following options are described: pumped energy transfer stations or PETS, compressed air energy storage or CAES, flywheels, various types of electrochemical batteries (lead, alkaline, sodium, lithium), metal air batteries, redox flow batteries, and super-capacitors. Thermal storage comprises power-to-heat and heat-to-power technologies. Hydrogen can be stored under different forms (compressed gas, liquid), in saline underground cavities, or by using water electrolysis and fuel cells. The authors propose an overview of the different services provided by energy storage to the electricity system, and discuss the main perspectives and challenges for tomorrow's storage (electric mobility, integration of renewable energies, electrification of isolated areas, scenarios of development)

Swiss pumped hydro storage potential for Germany's electricity system under high penetration of intermittent renewable energy

NARCIS (Netherlands)

van Meerwijk, Aagje J. H.; Benders, Reinerus; Davila-Martinez, Alejandro; Laugs, Gideon A. H.

2016-01-01

In order to cut greenhouse-gas emissions and increase energy security, the European Commission stimulates the deployment of intermittent renewable energy sources (IRES) towards 2050. In an electricity system with high shares of IRES implemented in the network, energy balancing like storage is needed
Cost-benefit assessment of energy storage for utility and customers: A case study in Malaysia

International Nuclear Information System (INIS)

Chua, Kein Huat; Lim, Yun Seng; Morris, Stella

2015-01-01

transmission and distribution infrastructure can be achieved with the installation of energy storage at distribution network.
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.
Energy storage: a review of recent literature

International Nuclear Information System (INIS)

Tatone, O.S.

1981-12-01

Recent literature on the technological and economic status of reversible energy storage has been reviewed. A broad range of research and development activities have been pursued between 1975 and the present. Most of this work has concentrated on improving technical and economic performance of previously known storage technologies. Hydraulic pumped storage with both reservoirs above ground and compressed air storage (1 plant) are the only methods that have been adopted by electric utilities. The need for electrical energy storage in Canada has not been acute because of the large proportion of hydraulic generation which incorporates some storge and, in most cases, can readily be used for load-following. Residential heat storage in ceramic room heaters has been used in Europe for several years. For Canadian climatic and market conditions larger, central heating units would be required. Residential heat storage depends upon utilities offering time-of-use rates and none in Canada do so at present. Most seasonal storage concepts depend upon storage of low-grade heat for district heating. The cost of energy storage is highly dependent upon annual energy throughput and hence favours smaller capacity systems operating on frequent charge/discharge cycles over long-term storage. Capital costs of energy storage methods from the literature, expressed in constant dollars, are compared graphically and tentative investment costs are presented for several storage methods
Inductive line energy storage generator

Energy Technology Data Exchange (ETDEWEB)

Choi, P [Ecole Polytechnique, Palaiseau (France). Laboratoire de Physique des Milieux Ionises

1997-12-31

The inductive energy storage (IES) generator has long been considered to be the most efficient system for energy usage in large pulsed power system at the MA level. A number of parameters govern the efficiency of energy transfer between the storage capacitors and the load, and the level of current deliverable to the load. For high power system, the energy storage capacitors are arranged as a Marx generator. The primary constraints are the inductances in the various parts of the circuit, in particular, the upstream inductance between the Marx and the POS, and the downstream inductance between the POS and the load. This paper deals with the effect of replacing part of the upstream inductance with a transmission line and introduces the new concept of an inductive line for energy storage (ILES). Extensive parametric scans were carried out on circuit simulations to investigate the effect of this upstream transmission line. A model was developed to explain the operation of the ILES design based on the data obtained. Comparison with an existing IES generator shows that the ILES design offers a significant improvement in the maximum current and hence energy delivered to an inductive load. (author). 5 figs., 1 ref.
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.
Solar applications of thermal energy storage. Final report

Energy Technology Data Exchange (ETDEWEB)

Lee, C.; Taylor, L.; DeVries, J.; Heibein, S.

1979-01-01

A technology assessment is presented on solar energy systems which use thermal energy storage. The study includes characterization of the current state-of-the-art of thermal energy storage, an assessment of the energy storage needs of solar energy systems, and the synthesis of this information into preliminary design criteria which would form the basis for detailed designs of thermal energy storage. (MHR)
Phase Change Materials for Thermal Energy Storage

OpenAIRE

Stiebra, L; Cabulis, U; Knite, M

2014-01-01

Phase change materials (PCMs) for thermal energy storage (TES) have become an important subject of research in recent years. Using PCMs for thermal energy storage provides a solution to increase the efficiency of the storage and use of energy in many domestic and industrial sectors. Phase change TES systems offer a number of advantages over other systems (e.g. chemical storage systems): particularly small temperature distance between the storage and retrieval cycles, small unit sizes and lo...
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
Superconducting magnetic energy storage for the disposal of fast reserve energy at the electrical energy supply. Supraleitende Energiespeicher zur Bereitstellung schneller Reserveleistung in der elektrischen Energieversorgung

Energy Technology Data Exchange (ETDEWEB)

Bayer, W [Siemens AG, Erlangen (Germany); Bittihn, R [Varta AG, Hagen (Germany); Kuerten, H [Siemens AG, Erlangen (Germany); Radtke, U [PreussenElektra AG, Hannover (Germany); Taube, W [PreussenElektra AG, Hannover (Germany); Vollmar, H E [Siemens AG, Erlangen (Germany); Willmes, H [Varta Batterie AG, Hagen (Germany)

1994-04-05

The authors investigate the economic efficiency of the application of a superconducting magnetic energy storage (SMES) in the field of electrical energy supply taking as example a network of 10 000 MW which is operated in an European interconnected power system. In case of this network the supply of the second reserve energy has become an interesting example of application, especially combined with the disconnection of the pre-heater. The application of SMES could lead to a better utilisation of existing power stations and the fuels along with a reduction of emissions. (orig.)
Energy storage in ceramic dielectrics

International Nuclear Information System (INIS)

Love, G.R.

1990-01-01

Historically, multilayer ceramic capacitors (MLC's) have not been considered for energy storage applications for two primary reasons. First, physically large ceramic capacitors were very expensive and, second, total energy density obtainable was not nearly so high as in electrolytic capacitor types. More recently, the fabrication technology for MLC's has improved significantly, permitting both significantly higher energy density and significantly lower costs. Simultaneously, in many applications, total energy storage has become smaller, and the secondary requirements of very low effective series resistance and effective series inductance (which, together, determine how efficiently the energy may be stored and recovered) have become more important. It is therefore desirable to reexamine energy storage in ceramics for contemporary commercial and near-commercial dielectrics. Stored energy is proportional to voltage squared only in the case of paraelectric insulators, because only they have capacitance that is independent of bias voltage. High dielectric constant materials, however, are ferroics (that is ferroelectric and/or antiferroelectric) and display significant variation of effective dielectric constant with bias voltage
Maximizing the energy storage performance of phase change thermal storage systems

Energy Technology Data Exchange (ETDEWEB)

Amin, N.A.M.; Bruno, F.; Belusko, M. [South Australia Univ., Mawson Lakes, South Australia (Australia). Inst. for Sustainable Systems and Technologies

2009-07-01

The demand for electricity in South Australia is highly influenced by the need for refrigeration and air-conditioning. An extensive literature review has been conducted on the use of phase change materials (PCMs) in thermal storage systems. PCMs use latent heat at the solid-liquid phase transition point to store thermal energy. They are considered to be useful as a thermal energy storage (TES) material because they can provide much higher energy storage densities compared to conventional sensible thermal storage materials. This paper reviewed the main disadvantages of using PCMs for energy storage, such as low heat transfer, super cooling and system design issues. Other issues with PCMs include incongruence and corrosion of heat exchanger surfaces. The authors suggested that in order to address these problems, future research should focus on maximizing heat transfer by optimizing the configuration of the encapsulation through a parametric analysis using a PCM numerical model. The effective conductivity in encapsulated PCMs in a latent heat thermal energy storage (LHTES) system can also be increased by using conductors in the encapsulation that have high thermal conductivity. 47 refs., 1 tab., 1 fig.
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.
A control model for district heating networks with storage

NARCIS (Netherlands)

Scholten, Tjeert; De Persis, Claudio; Tesi, Pietro

2014-01-01

In [1] pressure control of hydraulic networks is investigated. We extend this work to district heating systems with storage capabilities and derive a model taking the topology of the network into account. The goal for the derived model is that it should allow for control of the storage level and
Hybrid Hydrogen and Mechanical Distributed Energy Storage

Directory of Open Access Journals (Sweden)

Stefano Ubertini

2017-12-01

Full Text Available Effective energy storage technologies represent one of the key elements to solving the growing challenges of electrical energy supply of the 21st century. Several energy storage systems are available, from ones that are technologically mature to others still at a research stage. Each technology has its inherent limitations that make its use economically or practically feasible only for specific applications. The present paper aims at integrating hydrogen generation into compressed air energy storage systems to avoid natural gas combustion or thermal energy storage. A proper design of such a hybrid storage system could provide high roundtrip efficiencies together with enhanced flexibility thanks to the possibility of providing additional energy outputs (heat, cooling, and hydrogen as a fuel, in a distributed energy storage framework. Such a system could be directly connected to the power grid at the distribution level to reduce power and energy intermittence problems related to renewable energy generation. Similarly, it could be located close to the user (e.g., office buildings, commercial centers, industrial plants, hospitals, etc.. Finally, it could be integrated in decentralized energy generation systems to reduce the peak electricity demand charges and energy costs, to increase power generation efficiency, to enhance the security of electrical energy supply, and to facilitate the market penetration of small renewable energy systems. Different configurations have been investigated (simple hybrid storage system, regenerate system, multistage system demonstrating the compressed air and hydrogen storage systems effectiveness in improving energy source flexibility and efficiency, and possibly in reducing the costs of energy supply. Round-trip efficiency up to 65% can be easily reached. The analysis is conducted through a mixed theoretical-numerical approach, which allows the definition of the most relevant physical parameters affecting the system
Subcooled compressed air energy storage system for coproduction of heat, cooling and electricity

International Nuclear Information System (INIS)

Arabkoohsar, A.; Dremark-Larsen, M.; Lorentzen, R.; Andresen, G.B.

2017-01-01

Highlights: •A new configuration of compressed air energy storage system is proposed and analyzed. •This system, so-called subcooled-CAES, offers cogeneration of electricity, heat and cooling. •A pseudo-dynamic energy, exergy and economic analysis of the system for an entire year is presented. •The annual power, cooling and heat efficiencies of the system are around 31%, 32% and 92%. •The overall energy and exergy performance coefficients of the system are 1.55 and 0.48, respectively. -- Abstract: Various configurations of compressed air energy storage technology have received attention over the last years due to the advantages that this technology offers relative to other power storage technologies. This work proposes a new configuration of this technology aiming at cogeneration of electricity, heat and cooling. The new system may be very advantageous for locations with high penetration of renewable energy in the electricity grid as well as high heating and cooling demands. The latter would typically be locations with district heating and cooling networks. A thorough design, sizing and thermodynamic analysis of the system for a typical wind farm with 300 MW capacity in Denmark is presented. The results show a great potential of the system to support the local district heating and cooling networks and reserve services in electricity market. The values of power-to-power, power-to-cooling and power-to-heat efficiencies of this system are 30.6%, 32.3% and 92.4%, respectively. The exergy efficiency values are 30.6%, 2.5% and 14.4% for power, cooling and heat productions. A techno-economic comparison of this system with two of the most efficient previous designs of compressed air energy storage system proves the firm superiority of the new concept.
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.
Energy and Exergy Analysis of Ocean Compressed Air Energy Storage Concepts

Directory of Open Access Journals (Sweden)

Vikram C. Patil

2018-01-01

Full Text Available Optimal utilization of renewable energy resources needs energy storage capability in integration with the electric grid. Ocean compressed air energy storage (OCAES can provide promising large-scale energy storage. In OCAES, energy is stored in the form of compressed air under the ocean. Underwater energy storage results in a constant-pressure storage system which has potential to show high efficiency compared to constant-volume energy storage. Various OCAES concepts, namely, diabatic, adiabatic, and isothermal OCAES, are possible based on the handling of heat in the system. These OCAES concepts are assessed using energy and exergy analysis in this paper. Roundtrip efficiency of liquid piston based OCAES is also investigated using an experimental liquid piston compressor. Further, the potential of improved efficiency of liquid piston based OCAES with use of various heat transfer enhancement techniques is investigated. Results show that adiabatic OCAES shows improved efficiency over diabatic OCAES by storing thermal exergy in thermal energy storage and isothermal OCAES shows significantly higher efficiency over adiabatic and diabatic OCAES. Liquid piston based OCAES is estimated to show roundtrip efficiency of about 45% and use of heat transfer enhancement in liquid piston has potential to improve roundtrip efficiency of liquid piston based OCAES up to 62%.
Energy storage. The actual challenge for tomorrow

International Nuclear Information System (INIS)

Combe, Matthieu; Danielo, Olivier

2016-09-01

As methods of energy production are now diversified and efficient, the challenge is now their integration into the grid, and their storage. Thus, this publication first proposes a set of articles which address perspectives and realisations (or projects) related to energy storage: the challenge of modernisation of Pump Storage Power plants (PSP), the possibilities provided by power-to-gas technology to store electricity, the possibilities provided by coupling of CO 2 storage and geothermal energy. Other aspects concern electric power storage at the back end of the supply chain: the Corri-door project of 200 terminals for fast electric charging (for electric vehicles), the emergence of the domestic battery as storage mean in different counties. More prospective projects are also evoked: the use of hot water in Hawaii to store photovoltaic solar electricity and inspired projects by ENGIE and EDF, the perspective of energy storage on miniaturised chips, and a three-wheel light vehicle (Moe) using solar energy and developed by the Evovelo startup
Energy storage system for a pulsed DEMO

International Nuclear Information System (INIS)

Lucas, J.; Cortes, M.; Mendez, P.; Hayward, J.; Maisonnier, D.

2007-01-01

Several designs have been proposed for the DEMO fusion reactor. Some of them are working in a non-steady state mode. Since a power plant should be able to deliver to the grid a constant power, this challenge must be solved. Energy storage is required at a level of 250 MWh e with the capability of delivering a power of 1 GWe. A review of different technologies for energy storage is made. Thermal energy storage (TES), fuel cells and other hydrogen storage, compressed air storage, water pumping, batteries, flywheels and supercapacitors are the most promising solutions to energy storage. Each one is briefly described in the paper, showing its basis, features, advantages and disadvantages for this application. The conclusion of the review is that, based on existing technology, thermal energy storage using molten salts and a system based on hydrogen storage are the most promising candidates to meet the requirements of a pulsed DEMO. These systems are investigated in more detail together with an economic assessment of each

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.
The energy efficiency ratio of heat storage in one shell-and-one tube phase change thermal energy storage unit

International Nuclear Information System (INIS)

Wang, Wei-Wei; Wang, Liang-Bi; He, Ya-Ling

2015-01-01

Highlights: • A parameter to indicate the energy efficiency ratio of PCTES units is defined. • The characteristics of the energy efficiency ratio of PCTES units are reported. • A combined parameter of the physical properties of the working mediums is found. • Some implications of the energy efficiency ratio in design of PCTES units are analyzed. - Abstract: From aspect of energy consuming to pump heat transfer fluid, there is no sound basis on which to create an optimum design of a thermal energy storage unit. Thus, it is necessary to develop a parameter to indicate the energy efficiency of such unit. This paper firstly defines a parameter that indicates the ratio of heat storage of phase change thermal energy storage unit to energy consumed in pumping heat transfer fluid, which is called the energy efficiency ratio, then numerically investigates the characteristics of this parameter. The results show that the energy efficiency ratio can clearly indicate the energy efficiency of a phase change thermal energy storage unit. When the fluid flow of a heat transfer fluid is in a laminar state, the energy efficiency ratio is larger than in a turbulent state. The energy efficiency ratio of a shell-and-tube phase change thermal energy storage unit is more sensitive to the outer tube diameter. Under the same working conditions, within the heat transfer fluids studied, the heat storage property of the phase change thermal energy storage unit is best for water as heat transfer fluid. A combined parameter is found to indicate the effects of both the physical properties of phase change material and heat transfer fluid on the energy efficiency ratio
Applied research on energy storage and conversion for photovoltaic and wind energy systems. Volume II. Photovoltaic systems with energy storage. Final report

Energy Technology Data Exchange (ETDEWEB)

1978-01-01

This volume of the General Electric study was directed at an evaluation of those energy storage technologies deemed best suited for use in conjunction with a photovoltaic energy conversion system in utility, residential and intermediate applications. Break-even cost goals are developed for several storage technologies in each application. These break-even costs are then compared with cost projections presented in Volume I of this report to show technologies and time frames of potential economic viability. The form of the presentation allows the reader to use more accurate storage system cost data as they become available. The report summarizes the investigations performed and presents the results, conclusions and recommendations pertaining to use of energy storage with photovoltaic energy conversion systems. Candidate storage concepts studied include (1) above ground and underground pumped hydro, (2) underground compressed air, (3) electric batteries, (4) flywheels, and (5) hydrogen production and storage. (WHK)
High density energy storage capacitor

International Nuclear Information System (INIS)

Whitham, K.; Howland, M.M.; Hutzler, J.R.

1979-01-01

The Nova laser system will use 130 MJ of capacitive energy storage and have a peak power capability of 250,000 MW. This capacitor bank is a significant portion of the laser cost and requires a large portion of the physical facilities. In order to reduce the cost and volume required by the bank, the Laser Fusion Program funded contracts with three energy storage capacitor producers: Aerovox, G.E., and Maxwell Laboratories, to develop higher energy density, lower cost energy storage capacitors. This paper describes the designs which resulted from the Aerovox development contract, and specifically addresses the design and initial life testing of a 12.5 kJ, 22 kV capacitor with a density of 4.2 J/in 3 and a projected cost in the range of 5 cents per joule
Novel “open-sorption pipe” reactor for solar thermal energy storage

International Nuclear Information System (INIS)

Aydin, Devrim; Casey, Sean P.; Chen, Xiangjie; Riffat, Saffa

2016-01-01

Highlights: • A novel ‘open sorption pipe’ heat storage was experimentally investigated. • Effect of absolute moisture levels on heat storage performance was analyzed. • Hygrothermal-cyclic performances of Zeolite 13X and vermiculite–calcium chloride were compared. • Vermiculite–calcium chloride has more durable performance than Zeolite at 80 °C regeneration temperature. • Sorption pipe system using vermiculite–calcium chloride provides energy storage density of 290 kW h/m"3. - Abstract: In the last decade sorption heat storage systems are gaining attention due to their high energy storage density and long term heat storage potential. Sorption reactor development is vital for future progress of these systems however little has done on this topic. In this study, a novel sorption pipe reactor for solar thermal energy storage is developed and experimentally investigated to fulfill this gap. The modular heat storage system consists of sorption pipe units with an internal perforated diffuser pipe network and the sorption material filled in between. Vermiculite–calcium chloride composite material was employed as the sorbent in the reactor and its thermal performance was investigated under different inlet air humidity levels. It was found that, a fourfold increase of absolute humidity difference of air led to approximately 2.3 times boost in average power output from 313 W to 730 W and an 8.8 times boost of average exergy from 4.8 W to 42.3 W. According to the testing results, each of three sorption pipes can provide an average air temperature lift of 24.1 °C over 20 h corresponding to a system total energy storage capacity of 25.5 kW h and energy storage density of 290 kW h/m"3. Within the study, vermiculite–calcium chloride performance was also compared with the widely investigated Zeolite 13X. Vermiculite–calcium chloride showed a good cyclic ability at regeneration temperature of 80 °C with a steadier thermal performance than Zeolite
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)
Security for Network Attached Storage Devices

National Research Council Canada - National Science Library

Gobioff, Howard

1997-01-01

This paper presents a novel cryptographic capability system addressing the security and performance needs of network attached storage systems in which file management functions occur at a different...
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.
Economic Aspects of Innovations in Energy Storage

OpenAIRE

Strielkowski, Wadim; Lisin, Evgeny

2017-01-01

Energy storage is emerging as a potential method for addressing global energy system challenges across many different application areas. However, there are technical and non-technical barriers to the widespread deployment of energy storage devices. With regard to the above, it seems crucial to identify innovation processes, mechanisms and systems (in a broad sense) that can allow energy storage to help meet energy system challenges, and also deliver industrial growth from technology developme...
New technology and possible advances in energy storage

International Nuclear Information System (INIS)

Baker, John

2008-01-01

Energy storage technologies may be electrical or thermal. Electrical energy stores have an electrical input and output to connect them to the system of which they form part, while thermal stores have a thermal input and output. The principal electrical energy storage technologies described are electrochemical systems (batteries and flow cells), kinetic energy storage (flywheels) and potential energy storage, in the form of pumped hydro and compressed air. Complementary thermal storage technologies include those based on the sensible and latent heat capacity of materials, which include bulk and smaller-capacity hot and cold water storage systems, ice storage, phase change materials and specific bespoke thermal storage media. For the majority of the storage technologies considered here, the potential for fundamental step changes in performance is limited. For electrochemical systems, basic chemistry suggests that lithium-based technologies represent the pinnacle of cell development. This means that the greatest potential for technological advances probably lies in the incremental development of existing technologies, facilitated by advances in materials science, engineering, processing and fabrication. These considerations are applicable to both electrical and thermal storage. Such incremental developments in the core storage technologies are likely to be complemented and supported by advances in systems integration and engineering. Future energy storage technologies may be expected to offer improved energy and power densities, although, in practice, gains in reliability, longevity, cycle life expectancy and cost may be more significant than increases in energy/powerdensity per se
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 CO 2 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.
Storage Integration in Energy Systems: A New Perspective

International Nuclear Information System (INIS)

Faure-Schuyer, Aurelie

2016-06-01

Energy storage is partly an 'old story' and a new one. Energy storage is an essential stabilizing factor in existing electrical systems. Looking forward, energy storage is being considered as a key element of the transformation of energy systems, given the higher shares of renewable generation integrating the systems and demand-side management offered to end-customers. Today, the cost of electricity produced from battery storage is approaching parity with electricity bought from the grid. For this trend to gain strength and energy storage to be part of new business models, energy policies and regulatory frameworks need to be adapted. (author)
On Network Coded Distributed Storage

DEFF Research Database (Denmark)

Cabrera Guerrero, Juan Alberto; Roetter, Daniel Enrique Lucani; Fitzek, Frank Hanns Paul

2016-01-01

systems typically rely on expensive infrastructure with centralized control to store, repair and access the data. This approach introduces a large delay for accessing and storing the data driven in part by a high RTT between users and the cloud. These characteristics are at odds with the massive increase......This paper focuses on distributed fog storage solutions, where a number of unreliable devices organize themselves in Peer-to-Peer (P2P) networks with the purpose to store reliably their data and that of other devices and/or local users and provide lower delay and higher throughput. Cloud storage...... of devices and generated data in coming years as well as the requirements of low latency in many applications. We focus on characterizing optimal solutions for maintaining data availability when nodes in the fog continuously leave the network. In contrast with state-of-the-art data repair formulations, which...
Batteries and Energy Storage | Argonne National Laboratory

Science.gov (United States)

Skip to main content Argonne National Laboratory Toggle Navigation Toggle Search Energy Batteries Security User Facilities Science Work with Us Energy Batteries and Energy Storage Energy Systems Modeling Transportation SPOTLIGHT Batteries and Energy Storage Argonne's all- encompassing battery research program spans
Energy Storage System for a Pulsed DEMO

International Nuclear Information System (INIS)

Lucas, J.; Cortes, M.; Mendez, P.; Maisonnier, D.; Hayward, J.

2006-01-01

Several designs have been proposed for DEMO, some of which will operate in pulsed mode. Since a fusion power plant will be required to deliver continuous output, this challenge must be solved. For the reference DEMO, energy storage is required at a level of 250 MWhe with a capability of delivering a power of 1 GWe. Although DEMO is scheduled to be built in about 30 years, the design of the energy storage system must be based on current technology, focusing on commercially available products and on their expected future trends. From a thorough review of the different technologies available, thermal energy storage, compressed air energy storage, water pumping, fuel cells, batteries, flywheels and ultracapacitors are the most promising solutions to energy storage for a pulsed DEMO. An outline of each of these technologies is described in the paper, showing its basis, features, advantages and disadvantages for this application. Following this review, the most suitable methods capable of storing the required energy are examined. Fuel cells are not suitable due to the power requirement. Compressed air energy storage has a lower efficiency than the required one. Thermal energy storage, based on molten salts, so more energy can be stored with a better efficiency, and water pumping are shown as the main solutions, based on existing technology. However, those are not the only solutions capable of solving our challenge. Hydrogen production, using water electrolysis, hydrogen storage and combustion in a combined cycle can achieve our energy and power requirements with an acceptable efficiency. All these solutions are studied in detail and described, evaluating their current cost and efficiency in order to compare them all. (author)
Electricity storage. The problematic of alternative energies

International Nuclear Information System (INIS)

Hauet, Jean-Pierre

2013-01-01

After having evoked the increasing share of renewable energies in electricity production in Europe and the associated investments, the author outlines the main problems associated with renewable energy: their intermittency, and the fact that they are submitted to quick and important variations which must be managed by the grid. He also evokes economic and financial problems (high taxes in Germany and in France, mandatory purchase mechanisms leading to absurd situations and having consequences on the electricity market). The author discusses the issue of energy storage: storage is expensive and its cost will increase that of the produced energy. However, storage can be interesting if its cost is covered by the income generated by the provided services. Some solutions already exist: pumped-storage power station (PSPS), remotely controlled electric-storage water heaters. The author presents and comments the services which storage can provide: smoothing, spare energy supply, and supply quality. He outlines the importance of a technical-economic analysis for the choice of the best storage solution, but also the need to change the business model
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
Dependable Benchmarking for Storage Systems in High-Energy Physics

CERN Document Server

Fleri Soler, Edward

2017-01-01

In high-energy physics, storage systems play a crucial role to store and secure very valuable data produced by complex experiments. The effectiveness and efficiency of data acquisition systems of such experiments depends directly on those of these storage systems. Coping with present day rates and reliability requirements of such experiments implies operating high-performance hardware under the best possible conditions, with a broad set of hardware and software parameters existing along the hierarchical levels, from networks down to drives. An extensive number of tests are required for the tuning of parameters to achieve optimised I/O operations. Current approaches to I/O optimisation generally consist of manual test execution and result taking. This approach lacks appropriate modularity, durability and reproducibility, attainable through dedicated testing facilities. The aim of this project is to conceive a user-friendly, dedicated storage benchmarking tool for the improved comparison of I/O parameters in re...
Kinetic Storage as an Energy Management System

International Nuclear Information System (INIS)

Garcia-Tabares, L.

2007-01-01

The possibility of storing energy is increasingly important and necessary. The reason is that storage modifies the basic equation of the energy production balance which states that the power produced should equal the power consumed. When there is a storage device in the grid, this equation is modified such that, in the new balance, the energy produced should equal the algebraic sum of the energy consumed and the energy stored (positive in storage phase and negative when released). This means that the generation profile can be uncoupled from the consumption profile, with the resulting improvement of efficiency. Even small-sized storage systems can be very effective. (Author) 10 refs
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. [...

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.
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....... The results show that such options can enable an increased penetration of wind power. Using pumped hydro storage (PHS) may increase wind power penetration from 0.5 TWh, for existing PHS installations and up to 6 TWh for very large installations. Using large heat pumps and heat storages in combination...... with specific regulation of power system could additionally increase wind penetration for 0.37 TWh. Hence, with the current technologies installed in the Croatian energy system the installed pumped hydro- plant may facilitate more than 10% wind power in the electricity system. In future research more precise...
The energy challenge of a post-fossil world: Seasonal energy storage

International Nuclear Information System (INIS)

Forsberg, C.

2009-01-01

Fossil fuels are an energy source and an energy storage system. The demand for electricity and heat varies daily, weekly, and seasonally with seasonal variations often varying by a factor of two or more. The variable demand is met by fossil fuels because 1) fossil fuels are inexpensive to store in coal piles, oil tanks, and underground natural gas storage facilities and 2) the capital cost of the equipment to burn fossil fuels and convert the energy to heat or electricity is small relative to the cost of the fossil fuels. Concerns about climate change may limit the conventional use of fossil fuels. The alternative low-carbon energy production systems (nuclear, fossil fuels with carbon dioxide sequestration, wind, and solar) are capital-intensive energy sources with low operating costs. To obtain favorable economics these technologies must operate at full capacity; but, their output does not match energy demand. We have energy alternatives to fossil fuels but no replacements for the energy storage capabilities or fossil fuels. Proposed strategies and technologies to address the grand storage challenge (including seasonal storage of electricity) are described. The options suggest a nuclear-renewable future to address seasonal energy storage needs in a low-carbon world.
Battery energy storage systems: Assessment for small-scale renewable energy integration

Energy Technology Data Exchange (ETDEWEB)

Nair, Nirmal-Kumar C.; Garimella, Niraj [Power Systems Group, Department of Electrical and Computer Engineering, The University of Auckland, 38 Princes Street, Science Centre, Auckland 1142 (New Zealand)

2010-11-15

Concerns arising due to the variability and intermittency of renewable energy sources while integrating with the power grid can be mitigated to an extent by incorporating a storage element within the renewable energy harnessing system. Thus, battery energy storage systems (BESS) are likely to have a significant impact in the small-scale integration of renewable energy sources into commercial building and residential dwelling. These storage technologies not only enable improvements in consumption levels from renewable energy sources but also provide a range of technical and monetary benefits. This paper provides a modelling framework to be able to quantify the associated benefits of renewable resource integration followed by an overview of various small-scale energy storage technologies. A simple, practical and comprehensive assessment of battery energy storage technologies for small-scale renewable applications based on their technical merit and economic feasibility is presented. Software such as Simulink and HOMER provides the platforms for technical and economic assessments of the battery technologies respectively. (author)
Superconductive energy storage magnet study

International Nuclear Information System (INIS)

Rhee, S.W.

1982-01-01

Among many methods of energy storages the superconducting energy storage has been considered as the most promising method. Many related technical problems are still unsolved. One of the problems is the magnetizing and demagnetizing loss of superconducting coil. This loss is mainly because of hysteresis of pinning force. In this paper the hysteresis loss is calculated and field dependence of the a.c. losses is explained. The ratio of loss and stored energy is also calculated. (Author)
Energy storage device with large charge separation

Science.gov (United States)

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

2018-04-03

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.
Neural Network based Control of SG based Standalone Generating System with Energy Storage for Power Quality Enhancement

Science.gov (United States)

Nayar, Priya; Singh, Bhim; Mishra, Sukumar

2017-08-01

An artificial intelligence based control algorithm is used in solving power quality problems of a diesel engine driven synchronous generator with automatic voltage regulator and governor based standalone system. A voltage source converter integrated with a battery energy storage system is employed to mitigate the power quality problems. An adaptive neural network based signed regressor control algorithm is used for the estimation of the fundamental component of load currents for control of a standalone system with load leveling as an integral feature. The developed model of the system performs accurately under varying load conditions and provides good dynamic response to the step changes in loads. The real time performance is achieved using MATLAB along with simulink/simpower system toolboxes and results adhere to an IEEE-519 standard for power quality enhancement.
Energy-storage technologies and electricity generation

International Nuclear Information System (INIS)

Hall, Peter J.; Bain, Euan J.

2008-01-01

As the contribution of electricity generated from renewable sources (wind, wave and solar) grows, the inherent intermittency of supply from such generating technologies must be addressed by a step-change in energy storage. Furthermore, the continuously developing demands of contemporary applications require the design of versatile energy-storage/power supply systems offering wide ranges of power density and energy density. As no single energy-storage technology has this capability, systems will comprise combinations of technologies such as electrochemical supercapacitors, flow batteries, lithium-ion batteries, superconducting magnetic energy storage (SMES) and kinetic energy storage. The evolution of the electrochemical supercapacitor is largely dependent on the development of optimised electrode materials (tailored to the chosen electrolyte) and electrolytes. Similarly, the development of lithium-ion battery technology requires fundamental research in materials science aimed at delivering new electrodes and electrolytes. Lithium-ion technology has significant potential, and a step-change is required in order to promote the technology from the portable electronics market into high-duty applications. Flow-battery development is largely concerned with safety and operability. However, opportunities exist to improve electrode technology yielding larger power densities. The main barriers to overcome with regard to the development of SMES technology are those related to high-temperature superconductors in terms of their granular, anisotropic nature. Materials development is essential for the successful evolution of flywheel technology. Given the appropriate research effort, the key scientific advances required in order to successfully develop energy-storage technologies generally represent realistic goals that may be achieved by 2050
An Empirical Model for Energy Storage Systems

Energy Technology Data Exchange (ETDEWEB)

Rosewater, David Martin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Scott, Paul [TransPower, Poway, CA (United States)

2016-03-17

Improved models of energy storage systems are needed to enable the electric grid’s adaptation to increasing penetration of renewables. This paper develops a generic empirical model of energy storage system performance agnostic of type, chemistry, design or scale. Parameters for this model are calculated using test procedures adapted from the US DOE Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage. We then assess the accuracy of this model for predicting the performance of the TransPower GridSaver – a 1 MW rated lithium-ion battery system that underwent laboratory experimentation and analysis. The developed model predicts a range of energy storage system performance based on the uncertainty of estimated model parameters. Finally, this model can be used to better understand the integration and coordination of energy storage on the electric grid.
Optimal Power Flow in Microgrids with Energy Storage

DEFF Research Database (Denmark)

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

2013-01-01

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...
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…
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
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.”
Optimization of Experimental Model Parameter Identification for Energy Storage Systems

Directory of Open Access Journals (Sweden)

Rosario Morello

2013-09-01

Full Text Available The smart grid approach is envisioned to take advantage of all available modern technologies in transforming the current power system to provide benefits to all stakeholders in the fields of efficient energy utilisation and of wide integration of renewable sources. Energy storage systems could help to solve some issues that stem from renewable energy usage in terms of stabilizing the intermittent energy production, power quality and power peak mitigation. With the integration of energy storage systems into the smart grids, their accurate modeling becomes a necessity, in order to gain robust real-time control on the network, in terms of stability and energy supply forecasting. In this framework, this paper proposes a procedure to identify the values of the battery model parameters in order to best fit experimental data and integrate it, along with models of energy sources and electrical loads, in a complete framework which represents a real time smart grid management system. The proposed method is based on a hybrid optimisation technique, which makes combined use of a stochastic and a deterministic algorithm, with low computational burden and can therefore be repeated over time in order to account for parameter variations due to the battery’s age and usage.
Concrete thermal energy storage for steam generation

DEFF Research Database (Denmark)

Singh, Shobhana; Sørensen, Kim

2017-01-01

Establishing enhancement methods to develop cost-effective thermal energy storage technology requires a detailed analysis. In this paper, a numerical investigation of the concrete based thermal energy storage system is carried out. The storage system consists of a heat transfer fluid flowing inside...
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.
Distributed Cloud Storage Using Network Coding

OpenAIRE

Sipos, Marton A.; Fitzek, Frank; Roetter, Daniel Enrique Lucani; Pedersen, Morten Videbæk

2014-01-01

Distributed storage is usually considered within acloud provider to ensure availability and reliability of the data.However, the user is still directly dependent on the quality of asingle system. It is also entrusting the service provider with largeamounts of private data, which may be accessed by a successfulattack to that cloud system or even be inspected by governmentagencies in some countries. This paper advocates a generalframework for network coding enabled distributed storage overmulti...
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
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.
Kinetic energy storage system

Energy Technology Data Exchange (ETDEWEB)

Jaeggi, M.; Folini, P.

1983-09-03

A flywheel system for the purpose of energy storage in decentral solar- or wind energy plants is introduced. The system comprises a rotor made out of plastic fibre, a motor/generator serving as electro-mechanical energy converter and a frequency-voltage transformer serving as electric adapter. The storable energy quantity amounts to several kWh.

Superconductivity, energy storage and switching

International Nuclear Information System (INIS)

Laquer, H.L.

1974-01-01

The phenomenon of superconductivity can contribute to the technology of energy storage and switching in two distinct ways. On one hand the zero resistivity of the superconductor can produce essentially infinite time constants so that an inductive storage system can be charged from very low power sources. On the other hand, the recovery of finite resistivity in a normal-going superconducting switch can take place in extremely short times, so that a system can be made to deliver energy at a very high power level. Topics reviewed include: physics of superconductivity, limits to switching speed of superconductors, physical and engineering properties of superconducting materials and assemblies, switching methods, load impedance considerations, refrigeration economics, limitations imposed by present day and near term technology, performance of existing and planned energy storage systems, and a comparison with some alternative methods of storing and switching energy. (U.S.)
Energy networks - The data serving the energy transition

International Nuclear Information System (INIS)

2017-03-01

The complementary aspects of the electricity and gas transport networks open new perspectives for the construction of a global energy system that is smarter and oriented to the integration of renewable energies. Moving beyond existing cooperative projects on the security of supply, GRTgaz and RTE intend to draw benefit from the digital revolution to build a response to the regional issues of energy, transport and climate. The Open Data platform provides energy production and consumption data on national and local levels. Use of these multi-energy and multi-operator data will facilitate the development of local authority energy policies and contribute strongly to innovation. It will also contribute to the efficiency of stakeholders in the energy system to engage in more pertinent activities with regions. This first data set is part of the ongoing transparency approach adopted by GRTgaz and RTE to provide better information to citizens, regional authorities and economic actors, for use in developing and assessing energy policies. GRTgaz and RTE already operate web sites (Open Data RTE, Open Data GRTgaz) and applications (GRTgaz+ and eCO2mix), which provide open access to key data concerning energy transport networks. The new energy network data platform will be enriched over time with data from other electricity and gas infrastructure operators. RTE joins the Jupiter 1000 project driven by GRTgaz. The Jupiter 1000 project located in Fos-sur-Mer (Bouches-du-Rhone) is designed to test the technical and economic viability of the Power to Gas concept. This consists in transforming surplus electrical energy from renewable sources into methane by combining hydrogen with CO 2 , for injection and storage in gas networks. RTE has joined the Jupiter 1000 project driven by GRTgaz and featuring seven other industrial partners, with several objectives: manage its needs for flexibility, develop the integration of renewable energy sources and make a valuable contribution to the
Engineering Support for Handling Controller Conflicts in Energy Storage Systems Applications

Directory of Open Access Journals (Sweden)

Claudia Zanabria

2017-10-01

Full Text Available Energy storage systems will play a major role in the decarbonization of future sustainable electric power systems, allowing a high penetration of distributed renewable energy sources and contributing to the distribution network stability and reliability. To accomplish this, a storage system is required to provide multiple services such as self-consumption, grid support, peak-shaving, etc. The simultaneous activation of controllers operation may lead to conflicts, as a consequence the execution of committed services is not guaranteed. This paper presents and discusses a solution to the exposed issue by developing an engineering support approach to semi-automatically detect and handle conflicts for multi-usage storage systems applications. To accomplish that an ontology is developed and exploited by model-driven engineering mechanisms. The proposed approach is evaluated by implementing a use case example, where detection of conflicts is automatically done at an early design stage. Besides this, exploitable source code for conflicts resolution is generated and used during the design and prototype stages of controllers development. Thus, the proposed engineering support enhances the design and development of storage system controllers, especially for multi-usage applications.
Optimal Investment Planning of Bulk Energy Storage Systems

Directory of Open Access Journals (Sweden)

Dina Khastieva

2018-02-01

Full Text Available Many countries have the ambition to increase the share of renewable sources in electricity generation. However, continuously varying renewable sources, such as wind power or solar energy, require that the power system can manage the variability and uncertainty of the power generation. One solution to increase flexibility of the system is to use various forms of energy storage, which can provide flexibility to the system at different time ranges and smooth the effect of variability of the renewable generation. In this paper, we investigate three questions connected to investment planning of energy storage systems. First, how the existing flexibility in the system will affect the need for energy storage investments. Second, how presence of energy storage will affect renewable generation expansion and affect electricity prices. Third, who should be responsible for energy storage investments planning. This paper proposes to assess these questions through two different mathematical models. The first model is designed for centralized investment planning and the second model deals with a decentralized investment approach where a single independent profit maximizing utility is responsible for energy storage investments. The models have been applied in various case studies with different generation mixes and flexibility levels. The results show that energy storage system is beneficial for power system operation. However, additional regulation should be considered to achieve optimal investment and allocation of energy storage.
A Multiagent Energy Management System for a Small Microgrid Equipped with Power Sources and Energy Storage Units

Science.gov (United States)

Radziszewska, Weronika; Nahorski, Zbigniew

An Energy Management System (EMS) for a small microgrid is presented, with both demand and production side management. The microgrid is equipped with renewable and controllable power sources (like a micro gas turbine), energy storage units (batteries and flywheels). Energy load is partially scheduled to avoid extreme peaks of power demand and to possibly match forecasted energy supply from the renewable power sources. To balance the energy in the network on line, a multiagent system is used. Intelligent agents of each device are proactively acting towards balancing the energy in the network, and at the same time optimizing the cost of operation of the whole system. A semi-market mechanism is used to match a demand and a production of the energy. Simulations show that the time of reaching a balanced state does not exceed 1 s, which is fast enough to let execute proper balancing actions, e.g. change an operating point of a controllable energy source. Simulators of sources and consumption devices were implemented in order to carry out exhaustive tests.
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
Assessment of the impacts of the renewable energy and ICT driven energy transition on distribution networks

NARCIS (Netherlands)

Nijhuis, M.; Gibescu, M.; Cobben, J.F.G.

2015-01-01

The shift to more renewable electricity generation, electrification of heating and transportation and the rise of ICT and energy storage lead to changes in the distribution of electricity. To facilitate the transition towards a clean sustainable power system distribution network operators are
Energy storage, to make the wager to believe

International Nuclear Information System (INIS)

Signoret, Stephane; Guilhem, Jean; De Santis, Audrey; Kim, Caroline; Petitot, Pauline; Mary, Olivier

2016-01-01

After having evoked some examples and studies (an assessment of the costs of energy storage, an industrial perspective for sodium-ion batteries, the development of an energy recovery system for road transport), a first article discusses the importance of a right definition of energy storage, of its functions and development framework (how to store, where to store, at which price, in which context). A second article evokes the installation of Forsee Power (a leader in battery assembly) in France. A third article discusses how to couple renewable energies and local energy storage. While evoking the example of the LMP battery by Bollore, a fourth article outline the common benefits of high capacity batteries used in electric vehicles as well as in domestic applications or renewable energy supply schemes. The fifth article proposes an overview of researches for the improvement of energy storage solutions (study of battery ageing, use of super-capacitors, thermal storage in industry, a hybrid storage of renewable energy in overseas districts, use of nano-silicon to improve anodes, improvement of oxygen supply in fuel cells, development of very porous silicon layers for anodes). The sixth article discusses the development of a process by Babcok and the Cnim Group for a massive storage of energy by thermal accumulation for electric or thermal energy producers. The seventh and last article notices that the IRENA (International renewable energy Agency) outlined the role of energy storage for the development of rural areas and of islands which are disconnected from the grid
MRI device – alternative for electrical energy storage

Directory of Open Access Journals (Sweden)

Molokáč, Š.

2008-01-01

Full Text Available It is well known, that the electrical energy storage in the large scale is basically difficult process. Such a process is marked by the energy losses, as the conversion of electrical energy into another form, is most frequently for example mechanical, and then back to the primary electrical form. Though, the superconducting magnetic energy storage (SMES technology offers the energy storage in an unchanged form, which is advantageous primarily in the achieved efficiency. Magnetic resonance imaging (MRI devices, commonly used in the medical facilities are based on the application of superconducting magnet. After its rejection from operation, there is possibility of using such devices for energy storage purposes. Additionally, such a technology of storage is also ecological.
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.
Scattering-layer-induced energy storage function in polymer-based quasi-solid-state dye-sensitized solar cells.

Science.gov (United States)

Zhang, Xi; Jiang, Hongrui

2015-03-09

Photo-self-charging cells (PSCs) are compact devices with dual functions of photoelectric conversion and energy storage. By introducing a scattering layer in polymer-based quasi-solid-state dye-sensitized solar cells, two-electrode PSCs with highly compact structure were obtained. The charge storage function stems from the formed ion channel network in the scattering layer/polymer electrolyte system. Both the photoelectric conversion and the energy storage functions are integrated in only the photoelectrode of such PSCs. This design of PSC could continuously output power as a solar cell with considerable efficiency after being photo-charged. Such PSCs could be applied in highly-compact mini power devices.
The Design of Distributed Micro Grid Energy Storage System

Science.gov (United States)

Liang, Ya-feng; Wang, Yan-ping

2018-03-01

Distributed micro-grid runs in island mode, the energy storage system is the core to maintain the micro-grid stable operation. For the problems that it is poor to adjust at work and easy to cause the volatility of micro-grid caused by the existing energy storage structure of fixed connection. In this paper, an array type energy storage structure is proposed, and the array type energy storage system structure and working principle are analyzed. Finally, the array type energy storage structure model is established based on MATLAB, the simulation results show that the array type energy storage system has great flexibility, which can maximize the utilization of energy storage system, guarantee the reliable operation of distributed micro-grid and achieve the function of peak clipping and valley filling.
Metal hydride-based thermal energy storage systems

Science.gov (United States)

Vajo, John J.; Fang, Zhigang

2017-10-03

The invention provides a thermal energy storage system comprising a metal-containing first material with a thermal energy storage density of about 1300 kJ/kg to about 2200 kJ/kg based on hydrogenation; a metal-containing second material with a thermal energy storage density of about 200 kJ/kg to about 1000 kJ/kg based on hydrogenation; and a hydrogen conduit for reversibly transporting hydrogen between the first material and the second material. At a temperature of 20.degree. C. and in 1 hour, at least 90% of the metal is converted to the hydride. At a temperature of 0.degree. C. and in 1 hour, at least 90% of the metal hydride is converted to the metal and hydrogen. The disclosed metal hydride materials have a combination of thermodynamic energy storage densities and kinetic power capabilities that previously have not been demonstrated. This performance enables practical use of thermal energy storage systems for electric vehicle heating and cooling.
Demand Response and Energy Storage Integration Study

Energy Technology Data Exchange (ETDEWEB)

Ma, Ookie; Cheung, Kerry; Olsen, Daniel J.; Matson, Nance; Sohn, Michael D.; Rose, Cody M.; Dudley, Junqiao Han; Goli, Sasank; Kiliccote, Sila; Cappers, Peter; MacDonald, Jason; Denholm, Paul; Hummon, Marissa; Jorgenson, Jennie; Palchak, David; Starke, Michael; Alkadi, Nasr; Bhatnagar, Dhruv; Currier, Aileen; Hernandez, Jaci; Kirby, Brendan; O' Malley, Mark

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.
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).
Superconducting magnetic energy storage (SMES). Results of a technology assessment

International Nuclear Information System (INIS)

Fleischer, T.; Juengst, K.P.; Brandl, V.; Maurer, W.; Nieke, E.

1995-05-01

The authors report on results of a Technology Assessment study commissioned by the German Federal Ministry of Education, Science, Research and Technology. The objective of this study was to evaluate the potential of superconducting magnetic energy storage (SMES) technology with respect to the economical, political and organization structures in the Federal Republic of Germany. The main focus of the study was on the technical and economic potential of large-scale SMES for diurnal load levelling applications. It was shown that there is no demand for the development of large SMES in Germany in the short and medium term. A second range of applications investigated is storage of electric energy for immediate delivery or consumption of electric power in case of need or for periodic power supply within the range of seconds. Due to its excellent dynamic properties SMES has substantial advantages over conventional storage technologies in this field. For those so-called dynamic applications SMES of small and medium energy capacity are needed. It was shown that SMES may be economically attractive for the provision of spinning reserve capacity in electrical networks, in particular cases for power quality applications (uninterruptable power supply, UPS) and for the compensation of cyclic loads, as well as in some market niches. The use of SMES for storage of recuperated energy in electrical railway traction systems has been proven to be uneconomical. Mobile SMES applications are unrealistic due to technical and size limitations. In SMES systems the energy is stored in a magnetic field. Biological objects as well as technical systems in the vicinity of a SMES plant are exposed to this field. The knowledge on impacts of magnetic fields on sensitive technical systems as well as on living organisms and especially on effects on human health is rather small and quite uncertain. (orig./MM) [de
Delivery of video-on-demand services using local storages within passive optical networks.

Science.gov (United States)

Abeywickrama, Sandu; Wong, Elaine

2013-01-28

At present, distributed storage systems have been widely studied to alleviate Internet traffic build-up caused by high-bandwidth, on-demand applications. Distributed storage arrays located locally within the passive optical network were previously proposed to deliver Video-on-Demand services. As an added feature, a popularity-aware caching algorithm was also proposed to dynamically maintain the most popular videos in the storage arrays of such local storages. In this paper, we present a new dynamic bandwidth allocation algorithm to improve Video-on-Demand services over passive optical networks using local storages. The algorithm exploits the use of standard control packets to reduce the time taken for the initial request communication between the customer and the central office, and to maintain the set of popular movies in the local storage. We conduct packet level simulations to perform a comparative analysis of the Quality-of-Service attributes between two passive optical networks, namely the conventional passive optical network and one that is equipped with a local storage. Results from our analysis highlight that strategic placement of a local storage inside the network enables the services to be delivered with improved Quality-of-Service to the customer. We further formulate power consumption models of both architectures to examine the trade-off between enhanced Quality-of-Service performance versus the increased power requirement from implementing a local storage within the network.
Regenesys utility scale energy storage. Project summary

International Nuclear Information System (INIS)

2004-01-01

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
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.
Dependability of wind energy generators with short-term energy storage.

Science.gov (United States)

Sørensen, B

1976-11-26

Power fluctuations and power duration curves for wind energy generators, including energy storage facilities of a certain capacity, are compared to those of typical nuclear reactors. A storage system capable of delivering the yearly average power output for about 10 hours already makes the dependability of the wind energy system comparable to that of a typical nuclear plant.

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....
Grid scale energy storage in salt caverns

Energy Technology Data Exchange (ETDEWEB)

Crotogino, F.; Donadei, S.

2011-05-15

Fossil energy sources require some 20% of the annual consumption to be stored to secure emergency cover, cold winter supply, peak shaving, seasonal swing, load management and energy trading. Today the electric power industry benefits from the extreme high energy density of fossil and nuclear fuels. This is one important reason why e.g. the German utilities are able to provide highly reliable grid operation at a electric power storage capacity at their pumped hydro power stations of less then 1 hour (40 GWh) related to the total load in the grid - i.e. only 0,06% compared to 20% for natural gas. Along with the changeover to renewable wind-and to a lesser extent PV-based electricity production this 'outsourcing' of storage services to fossil and nuclear fuels will decline. One important way out will be grid scale energy storage in geological formations. The present discussion, research projects and plans for balancing short term wind and solar power fluctuations focus primarily on the installation of Compressed Air Energy Storages (CAES) if the capacity of existing pumped hydro plants cannot be expanded, e.g. because of environmental issues or lack of suitable topography. Because of their small energy density, these storage options are, however, generally less suitable for balancing for longer term fluctuations in case of larger amounts of excess wind power, wind flaws or even seasonal fluctuations. One important way out are large underground hydrogen storages which provide a much higher energy density because of chemical energy bond. Underground hydrogen storage is state of the art since many years in Great Britain and in the USA for the (petro-) chemical industry. (Author)
Grid scale energy storage in salt caverns

Energy Technology Data Exchange (ETDEWEB)

Crotogino, Fritz; Donadei, Sabine [KBB Underground Technologies GmbH, Hannover (Germany)

2009-07-01

Fossil energy sources require some 20% of the annual consumption to be stored to secure emergency cover, peak shaving, seasonal balancing, etc. Today the electric power industry benefits from the extreme high energy density of fossil fuels. This is one important reason why the German utilities are able to provide highly reliable grid operation at a electric power storage capacity at their pumped hydro power stations of less then 1 hour (40 GWh) related to the total load in the grid - i.e. only 0,06% related to natural gas. Along with the changeover to renewable wind based electricity production this ''outsourcing'' of storage services to fossil fuels will decline. One important way out will be grid scale energy storage. The present discussion for balancing short term wind and solar power fluctuations focuses primarily on the installation of Compressed Air Energy Storages (CAES) in addition to existing pumped hydro plants. Because of their small energy density, these storage options are, however, generally not suitable for balancing for longer term fluctuations in case of larger amounts of excess wind power or even seasonal fluctuations. Underground hydrogen storages, however, provide a much higher energy density because of chemical energy bond - standard practice since many years. The first part of the article describes the present status and performance of grid scale energy storages in geological formations, mainly salt caverns. It is followed by a compilation of generally suitable locations in Europe and particularly Germany. The second part deals with first results of preliminary investigations in possibilities and limits of offshore CAES power stations. (orig.)
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.
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.
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.
Optimal Scheduling for Energy Harvesting Transmitters with Hybrid Energy Storage

OpenAIRE

Ozel, Omur; Shahzad, Khurram; Ulukus, Sennur

2013-01-01

We consider data transmission with an energy harvesting transmitter which has a hybrid energy storage unit composed of a perfectly efficient super-capacitor (SC) and an inefficient battery. The SC has finite space for energy storage while the battery has unlimited space. The transmitter can choose to store the harvested energy in the SC or in the battery. The energy is drained from the SC and the battery simultaneously. In this setting, we consider the offline throughput maximization problem ...
Cost allocation model for distribution networks considering high penetration of distributed energy resources

DEFF Research Database (Denmark)

Soares, Tiago; Pereira, Fábio; Morais, Hugo

2015-01-01

The high penetration of distributed energy resources (DER) in distribution networks and the competitive environment of electricity markets impose the use of new approaches in several domains. The network cost allocation, traditionally used in transmission networks, should be adapted and used...... in the distribution networks considering the specifications of the connected resources. The main goal is to develop a fairer methodology trying to distribute the distribution network use costs to all players which are using the network in each period. In this paper, a model considering different type of costs (fixed......, losses, and congestion costs) is proposed comprising the use of a large set of DER, namely distributed generation (DG), demand response (DR) of direct load control type, energy storage systems (ESS), and electric vehicles with capability of discharging energy to the network, which is known as vehicle...
Structure requirements for magnetic energy storage devices

International Nuclear Information System (INIS)

Eyssa, Y.M.; Huang, X.

1993-01-01

Large variety of large and small magnetic energy storage systems have been designed and analyzed in the last 20 years. Cryoresistive and superconductive energy storage (SMES) magnets have been considered for applications such as load leveling for electric utilities, pulsed storage for electromagnetic launchers and accelerator devices, and space borne superconductive energy storage systems. Large SMES are supported by a combination of cold and warm structure while small SMES are supported only by cold structure. In this article we provide analytical and numerical tools to estimate the structure requirements as function of the stored energy and configuration. Large and small solenoidal and toroidal geometries are used. Considerations for both warm and cold structure are discussed. Latest design concepts for both large and small units are included. (orig.)
ENERGY STAR Certified Data Center Storage

Science.gov (United States)

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 December 2, 2013. A detailed listing of key efficiency criteria are available at http://www.energystar.gov/certified-products/detail/data_center_storage
Battery energy storage market feasibility study - Expanded report

International Nuclear Information System (INIS)

Kraft, S.; Akhil, A.

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)
University of Arizona Compressed Air Energy Storage

Energy Technology Data Exchange (ETDEWEB)

Simmons, Joseph [Univ. of Arizona, Tucson, AZ (United States); Muralidharan, Krishna [Univ. of Arizona, Tucson, AZ (United States)

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.
Status of electrical energy storage systems

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-07-01

This report presents an overview of the status of electrical storage systems in the light of the growing use of renewable energy sources and distributed generation (DG) in meeting emission targets and in the interest of the UK electricity supply industry. Examples of storage technologies, their applications and current status are examined along with technical issues and possible activities by UK industries. Details are given of development opportunities in the fields of flow cells, advanced batteries - lithium batteries, high temperature batteries, flywheels, and capacitors. Power conversion systems and system integration, the all-electric ship project, and compressed air energy storage are discussed. Opportunities for development and deployment, small scale systems, demonstration programmes, and research and development issues are considered. An outline of the US Department of Energy Storage programme is given in the Annex to the report.
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.
Multi-Agent-Based Controller for Voltage Enhancement in AC/DC Hybrid Microgrid Using Energy Storages

Directory of Open Access Journals (Sweden)

Ahmadali Khatibzadeh

2017-02-01

Full Text Available Development of renewable energies and DC loads have led microgrids toward the creation of DC networks. The predictions show that the hybrid microgrids will be used widely in the future. This article has studied the voltage stability in the presence of sources of energy storage in AC/DC hybrid networks. However, because the different dynamics of hybrid networks applying centralized and distributed controllers will be faced with different problems, in this study, a multi-agent control for the microgrid has been used. A new structure referred to here as an event-driven microgrid control management (EDMCM has been developed to control the microgrid. This method increases response speed and accuracy of decision making. Hybrid Network Simulation results confirm the validity of the developed model.
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.
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.
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
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.
CALORSTOCK'94. Thermal energy storage. Better economy, environment, technology

International Nuclear Information System (INIS)

Kangas, M.T.; Lund, P.D.

1994-01-01

This publication is the first volume of the proceedings of CALORSTOCK'94, the sixth international conference on thermal energy storage held in Espoo, Finland on August 22-25, 1994. This volume contains 58 presentations from the following six sessions: Aquifer storage, integration into energy systems, Simulation models and design tools, IEA energy conservation through energy storage programme workshop, Earth coupled storage, District heating and utilities

A virtual network computer's optical storage virtualization scheme

Science.gov (United States)

Wang, Jianzong; Hu, Huaixiang; Wan, Jiguang; Wang, Peng

2008-12-01

In this paper, we present the architecture and implementation of a virtual network computers' (VNC) optical storage virtualization scheme called VOSV. Its task is to manage the mapping of virtual optical storage to physical optical storage, a technique known as optical storage virtualization. The design of VOSV aims at the optical storage resources of different clients and servers that have high read-sharing patterns. VOSV uses several schemes such as a two-level Cache mechanism, a VNC server embedded module and the iSCSI protocols to improve the performance. The results measured on the prototype are encouraging, and indicating that VOSV provides the high I/O performance.
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.
An Improved Genetic Algorithm for Optimal Stationary Energy Storage System Locating and Sizing

Directory of Open Access Journals (Sweden)

Bin Wang

2014-10-01

Full Text Available The application of a stationary ultra-capacitor energy storage system (ESS in urban rail transit allows for the recuperation of vehicle braking energy for increasing energy savings as well as for a better vehicle voltage profile. This paper aims to obtain the best energy savings and voltage profile by optimizing the location and size of ultra-capacitors. This paper firstly raises the optimization objective functions from the perspectives of energy savings, regenerative braking cancellation and installation cost, respectively. Then, proper mathematical models of the DC (direct current traction power supply system are established to simulate the electrical load-flow of the traction supply network, and the optimization objections are evaluated in the example of a Chinese metro line. Ultimately, a methodology for optimal ultra-capacitor energy storage system locating and sizing is put forward based on the improved genetic algorithm. The optimized result shows that certain preferable and compromised schemes of ESSs’ location and size can be obtained, acting as a compromise between satisfying better energy savings, voltage profile and lower installation cost.
Storage of intermittent energies. From self-consumption to huge photovoltaic power plants

International Nuclear Information System (INIS)

Perrin, Marion; Martin, Nicolas

2013-01-01

Power grids are evolving rapidly due to an increased use of decentralized power units, mostly based on intermittent renewable energy resources and due also to new ways of consuming energy (e.g. electrical vehicles). In the same time, the performance increase of new technologies such as telecommunications and storage systems could provide solutions for optimizing the electrical system. In this context, we are more and more talking about the 'smart-grids concept' because in parallel to the power interconnection, we also create communication networks which allow knowing in real time the status of the power grid, and so that the power flows can be controlled in an optimal way. In this article, we investigate challenges and opportunities for managing intermittent energy sources by using energy storage systems, from the consumer level to the grid operator. First we describe how the feed-in tariff could evolve in order to improve grid integration of large solar plants. We showed that behind the constraints due to the coupling of the power plants with a storage system, we could imagine lots of opportunities to diversify the business model. Then we evaluate the medium size PV with storage installation at the community level. For this purpose, we describe the local problems induced by the PV integration before proposing new ways to manage these systems. Finally, the self-consumption business model is investigated in terms of performance for the consumer and for the grid operator. (authors)
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.
Innovative Business Cases for Energy Storage In a Restructured Electricity Marketplace, A Study for the DOE Energy Storage Systems Program

Energy Technology Data Exchange (ETDEWEB)

IANNUCCI, JOE; EYER, JIM; BUTLER, PAUL C.

2003-02-01

This report describes the second phase of a project entitled ''Innovative Business Cases for Energy Storage in a Restructured Electricity Marketplace''. During part one of the effort, nine ''Stretch Scenarios'' were identified. They represented innovative and potentially significant uses of electric energy storage. Based on their potential to significantly impact the overall energy marketplace, the five most compelling scenarios were identified. From these scenarios, five specific ''Storage Market Opportunities'' (SMOs) were chosen for an in-depth evaluation in this phase. The authors conclude that some combination of the Power Cost Volatility and the T&D Benefits SMOs would be the most compelling for further investigation. Specifically, a combination of benefits (energy, capacity, power quality and reliability enhancement) achievable using energy storage systems for high value T&D applications, in regions with high power cost volatility, makes storage very competitive for about 24 GW and 120 GWh during the years of 2001 and 2010.
Stationary flywheel energy storage

Energy Technology Data Exchange (ETDEWEB)

Gilhaus, A; Hau, E; Gassner, G; Huss, G; Schauberger, H

1981-01-01

The aim of this system study is to find out industrial applications of stationary flywheel energy accumulators. The economic value for the consumer and the effects on the power supply grid are investigated. Up to now, stationary flywheel energy accumulators have only been used in a small range. The main reason for thinking of the application in a wider range was the hope that those could be used economically for lowering the maximum output demand of the power supply grid. The possible savings in energy costs, however, proved to be too small for paying back the investment costs. Further benefits are necessary for advantageous application. As to overall economy, compensation of short time maximum power output seems to be more favorable at the power stations. An additional possibility for energy storage by flywheels is given where otherwise lost energy can be used effectively, according to the successful brake energy storage in vehicles. Under this aspect the future use of flywheels in wind-power-plants seems to be promising. Attractive savings of energy can be obtained by introducing modern flywheel technology for emergency power supply units which are employed for instance in telecommunication systems. Especially the application for emergency power supply, in power stations and in combustion with wind energy converters need further investigation.
Using MRI devices for the energy storage purposes

Directory of Open Access Journals (Sweden)

Štefan Molokáč

2007-04-01

Full Text Available It is well known, that the electrical energy storage in the large scale is basically a difficult process. Such a process is connected with energy losses, as most frequently it is the conversion of electrical energy into another form, for example mechanical, and then back to the primal electrical form. Though, the SMES technology offers the energy storage in an unchanged form, which is advantageous primarily in the achieved efficiency. The magnetic resonance imaging (MRI devices, commonly used in the medical facilities are based on the basis of superconducting magnet. After its rejection from operation, (basically caused only by its „software fustiness“ and not by functional faults, there is a possibility of using such devices for the energy storage purposes. Additionally, such a technology of storage is also ecological. A research project is running at the Faculty of Mining, Ecology, Process Control and Geotechnologies (F BERG, the Department of Business and Management, in the field of using rejected MRI for energy storage purposes.
Economic competitiveness of underground coal gasification combined with carbon capture and storage in the Bulgarian energy network

Energy Technology Data Exchange (ETDEWEB)

Nakaten, Natalie Christine

2014-11-15

Underground coal gasification (UCG) allows for exploitation of deep-seated coal seams not economically exploitable by conventional coal mining. Aim of the present study is to examine UCG economics based on coal conversion into a synthesis gas to fuel a combined cycle gas turbine power plant (CCGT) with CO2 capture and storage (CCS). Thereto, a techno-economic model is developed for UCG-CCGT-CCS costs of electricity (COE) determination which, considering sitespecific data of a selected target area in Bulgaria, sum up to 72 Euro/MWh in total. To quantify the impact of model constraints on COE, sensitivity analyses are undertaken revealing that varying geological model constraints impact COE with 0.4% to 4%, chemical with 13%, technical with 8% to 17% and market-dependent with 2% to 25%. Besides site-specific boundary conditions, UCG-CCGT-CCS economics depend on resources availability and infrastructural characteristics of the overall energy system. Assessing a model based implementation of UCG-CCGT-CCS and CCS power plants into the Bulgarian energy network revealed that both technologies provide essential and economically competitive options to achieve the EU environmental targets and a complete substitution of gas imports by UCG synthesis gas production.
Economic competitiveness of underground coal gasification combined with carbon capture and storage in the Bulgarian energy network

International Nuclear Information System (INIS)

Nakaten, Natalie Christine

2014-01-01

Underground coal gasification (UCG) allows for exploitation of deep-seated coal seams not economically exploitable by conventional coal mining. Aim of the present study is to examine UCG economics based on coal conversion into a synthesis gas to fuel a combined cycle gas turbine power plant (CCGT) with CO2 capture and storage (CCS). Thereto, a techno-economic model is developed for UCG-CCGT-CCS costs of electricity (COE) determination which, considering sitespecific data of a selected target area in Bulgaria, sum up to 72 Euro/MWh in total. To quantify the impact of model constraints on COE, sensitivity analyses are undertaken revealing that varying geological model constraints impact COE with 0.4% to 4%, chemical with 13%, technical with 8% to 17% and market-dependent with 2% to 25%. Besides site-specific boundary conditions, UCG-CCGT-CCS economics depend on resources availability and infrastructural characteristics of the overall energy system. Assessing a model based implementation of UCG-CCGT-CCS and CCS power plants into the Bulgarian energy network revealed that both technologies provide essential and economically competitive options to achieve the EU environmental targets and a complete substitution of gas imports by UCG synthesis gas production.
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.
EPR ohmic heating energy storage

International Nuclear Information System (INIS)

Heck, F.M.; Stillwagon, R.E.; King, E.I.

1977-01-01

The Ohmic Heating (OH) Systems for all the Experimental Power Reactor (EPR) designs to date have all used temporary energy storage to assist in providing the OH current charge required to build up the plasma current. The energies involved (0.8 x 10 9 J to 1.9 x 10 9 J) are so large as to make capacitor storage impractical. Two alternative approaches are homopolar dc generators and ac generators. Either of these can be designed for pulse duty and can be made to function in a manner similar to a capacitor in the OH circuit and are therefore potential temporary energy storage devices for OH systems for large tokamaks. This study compared total OH system costs using homopolar and ac generators to determine their relative merits. The total system costs were not significantly different for either type of machine. The added flexibility and the lower maintenance of the ac machine system make it the more attractive approach
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.
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.
Peak reduction for commercial buildings using energy storage

Science.gov (United States)

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

2017-11-01

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

Science.gov (United States)

Brantley, L. W. J.; Rupp, C.

1982-01-01

Space-platform energy-storage and attitude-stabilization system utilizes variable moment of inertia of two masses attached to ends of retractable cable. System would be brought to its initial operating speed by gravity-gradient pumping. When fully developed, concept could be part of an orbiting solar-energy collection system. Energy would be temporarily stored in system then transmitted to Earth by microwaves or other method.
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.
The stationary storage of energy. Available technologies and CEA researches

International Nuclear Information System (INIS)

2012-01-01

After a discussion of the main challenges related to the stationary storage of energy, this publication proposes an overview of the different available technologies: plant for transfer of energy by pumping, compressed air, energy flywheels, hydrogen, lithium-ion battery, redox-flow battery, thermal storage by sensitive heat, thermal-chemical storage coupled to a thermal solar system, thermal storage by phase change, superconductive inductance storage, super-capacitors. It discusses the criteria of choice of storage technology, either for electric energy storage or for heat storage. It proposes an overview of researches performed within the CEA on storage systems: electrochemical, thermal, and hydrogen-based storages. The final chapter addresses current fundamental researches on storage in the field of lithium-ion batteries, hydrogen as a fuel, and thermoelectricity
Thermal analysis of near-isothermal compressed gas energy storage system

International Nuclear Information System (INIS)

Odukomaiya, Adewale; Abu-Heiba, Ahmad; Gluesenkamp, Kyle R.; Abdelaziz, Omar; Jackson, Roderick K.; Daniel, Claus; Graham, Samuel; Momen, Ayyoub M.

2016-01-01

Highlights: • A novel, high-efficiency, scalable, near-isothermal, energy storage system is introduced. • A comprehensive analytical physics-based model for the system is presented. • Efficiency improvement is achieved via heat transfer enhancement and use of waste heat. • Energy storage roundtrip efficiency (RTE) of 82% and energy density of 3.59 MJ/m"3 is shown. - Abstract: Due to the increasing generation capacity of intermittent renewable electricity sources and an electrical grid ill-equipped to handle the mismatch between electricity generation and use, the need for advanced energy storage technologies will continue to grow. Currently, pumped-storage hydroelectricity and compressed air energy storage are used for grid-scale energy storage, and batteries are used at smaller scales. However, prospects for expansion of these technologies suffer from geographic limitations (pumped-storage hydroelectricity and compressed air energy storage), low roundtrip efficiency (compressed air energy storage), and high cost (batteries). Furthermore, pumped-storage hydroelectricity and compressed air energy storage are challenging to scale-down, while batteries are challenging to scale-up. In 2015, a novel compressed gas energy storage prototype system was developed at Oak Ridge National Laboratory. In this paper, a near-isothermal modification to the system is proposed. In common with compressed air energy storage, the novel storage technology described in this paper is based on air compression/expansion. However, several novel features lead to near-isothermal processes, higher efficiency, greater system scalability, and the ability to site a system anywhere. The enabling features are utilization of hydraulic machines for expansion/compression, above-ground pressure vessels as the storage medium, spray cooling/heating, and waste-heat utilization. The base configuration of the novel storage system was introduced in a previous paper. This paper describes the results
Research for superconducting energy storage patterns and its practical countermeasures

Energy Technology Data Exchange (ETDEWEB)

Lin, D.H., E-mail: lindehua_cn@yahoo.com.cn [College of Physics, Chongqing University, JD Duz (USA)-CQU Institute for Superconductivity, Chongqing 400030 (China); Cui, D.J.; Li, B.; Teng, Y.; Zheng, G.L. [College of Physics, Chongqing University, JD Duz (USA)-CQU Institute for Superconductivity, Chongqing 400030 (China); Wang, X.Q. [College of Physics, Chongqing University, JD Duz (USA)-CQU Institute for Superconductivity, Chongqing 400030 (China); State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400030 (China)

2013-10-15

Highlights: • Proposed some new ideas and strategies about how to improve the energy storage density for SMES system. • Increasing the effective current density in the superconducting coils or optimizing the configuration of the SMES coil could improve the energy storage density. • A new conceive of energy compression is also proposed. -- Abstract: 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.

Research for superconducting energy storage patterns and its practical countermeasures

International Nuclear Information System (INIS)

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

2013-01-01

Highlights: • Proposed some new ideas and strategies about how to improve the energy storage density for SMES system. • Increasing the effective current density in the superconducting coils or optimizing the configuration of the SMES coil could improve the energy storage density. • A new conceive of energy compression is also proposed. -- Abstract: 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
A micro-grid operation analysis for cost-effective battery energy storage and RES plants integration

International Nuclear Information System (INIS)

Barelli, L.; Bidini, G.; Bonucci, F.

2016-01-01

Penetration of renewable energy is strongly slowed by its characteristic intermittency and fluctuating trend and by the inadequacy of electricity networks. These issues can be addressed through the development of new or improved storage technologies with higher performance, availability, durability, safety and lower costs. In the present work, micro-grids characterized by the presence of different subsections including renewable plants coupled with batteries storage solution are investigated through the development of a suitable code. Several design conditions and features, related to RES plant, storage system and users, were considered in order to realize a sensitivity analysis aimed to examine, on a yearly base and with one minute time step, interactions among the different micro-grid subsections and to identify the best solutions from both economic and energy point of views. - Highlights: • Storage systems coupling to RES plants is investigated for micro-grids. • Interactions between RES plants, storage batteries and users are analyzed. • Self-consumption increases with storage installation. • Investment pay-back analysis is performed varying plant configurations. • Pay-back reduction up to 30–40% for new RES/Storage integrated installations.
Graphene hybridization for energy storage applications.

Science.gov (United States)

Li, Xianglong; Zhi, Linjie

2018-05-08

Graphene has attracted considerable attention due to its unique two-dimensional structure, high electronic mobility, exceptional thermal conductivity, excellent optical transmittance, good mechanical strength, and ultrahigh surface area. To meet the ever increasing demand for portable electronic products, electric vehicles, smart grids, and renewable energy integrations, hybridizing graphene with various functions and components has been demonstrated to be a versatile and powerful strategy to significantly enhance the performance of various energy storage systems such as lithium-ion batteries, supercapacitors and beyond, because such hybridization can result in synergistic effects that combine the best merits of involved components and confer new functions and properties, thereby improving the charge/discharge efficiencies and capabilities, energy/power densities, and cycle life of these energy storage systems. This review will focus on diverse graphene hybridization principles and strategies for energy storage applications, and the proposed outline is as follows. First, graphene and its fundamental properties, followed by graphene hybrids and related hybridization motivation, are introduced. Second, the developed hybridization formulas of using graphene for lithium-ion batteries are systematically categorized from the viewpoint of material structure design, bulk electrode construction, and material/electrode collaborative engineering; the latest representative progress on anodes and cathodes of lithium-ion batteries will be reviewed following such classifications. Third, similar hybridization formulas for graphene-based supercapacitor electrodes will be summarized and discussed as well. Fourth, the recently emerging hybridization formulas for other graphene-based energy storage devices will be briefed in combination with typical examples. Finally, future prospects and directions on the exploration of graphene hybridization toward the design and construction of
Energy storage management system with distributed wireless sensors

Science.gov (United States)

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.
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.
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.)
Thermodynamic analysis of a compressed carbon dioxide energy storage system using two saline aquifers at different depths as storage reservoirs

International Nuclear Information System (INIS)

Liu, Hui; He, Qing; Borgia, Andrea; Pan, Lehua; Oldenburg, Curtis M.

2016-01-01

Highlights: • A compressed CO_2 energy storage system using two storage reservoirs is presented. • Compressed CO_2 energy storage density is higher than that of CAES. • The effects of storage reservoir pressure on the system performance are studied. - Abstract: Compressed air energy storage (CAES) is one of the leading large-scale energy storage technologies. However, low thermal efficiency and low energy storage density restrict its application. To improve the energy storage density, we propose a two-reservoir compressed CO_2 energy storage system. We present here thermodynamic and parametric analyses of the performance of an idealized two-reservoir CO_2 energy storage system under supercritical and transcritical conditions using a steady-state mathematical model. Results show that the transcritical compressed CO_2 energy storage system has higher round-trip efficiency and exergy efficiency, and larger energy storage density than the supercritical compressed CO_2 energy storage. However, the configuration of supercritical compressed CO_2 energy storage is simpler, and the energy storage densities of the two systems are both higher than that of CAES, which is advantageous in terms of storage volume for a given power rating.
Thermal energy storage based on cementitious materials: A review

Directory of Open Access Journals (Sweden)

Khadim Ndiaye

2018-01-01

Full Text Available Renewable energy storage is now essential to enhance the energy performance of buildings and to reduce their environmental impact. Many heat storage materials can be used in the building sector in order to avoid the phase shift between solar radiation and thermal energy demand. However, the use of storage material in the building sector is hampered by problems of investment cost, space requirements, mechanical performance, material stability, and high storage temperature. Cementitious material is increasingly being used as a heat storage material thanks to its low price, mechanical performance and low storage temperature (generally lower than 100 °C. In addition, cementitious materials for heat storage have the prominent advantage of being easy to incorporate into the building landscape as self-supporting structures or even supporting structures (walls, floor, etc.. Concrete solutions for thermal energy storage are usually based on sensible heat transfer and thermal inertia. Phase Change Materials (PCM incorporated in concrete wall have been widely investigated in the aim of improving building energy performance. Cementitious material with high ettringite content stores heat by a combination of physical (adsorption and chemical (chemical reaction processes usable in both the short (daily, weekly and long (seasonal term. Ettringite materials have the advantage of high energy storage density at low temperature (around 60 °C. The encouraging experimental results in the literature on heat storage using cementitious materials suggest that they could be attractive in a number of applications. This paper summarizes the investigation and analysis of the available thermal energy storage systems using cementitious materials for use in various applications.
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.
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.
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.
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
Posibilities of electric power storage from renewable sources

Directory of Open Access Journals (Sweden)

Petr Bača

2010-07-01

Full Text Available This paper presents an overview of all currently commercially available options of energy storage in the power distributionnetwork. The paper puts forward arguments for energy storage in the distribution network as well as requirements that must be metby the relevant energy storage systems. The paper describes 7 technologies allowing the solution of energy storage problems, includingtheir basic principles and summarizing benefits and drawbacks of individual solutions.
Magnetic energy storage

International Nuclear Information System (INIS)

Rogers, J.D.

1980-01-01

The fusion program embraces low loss superconductor strand development with integration into cables capable of carrying 50 kA in pulsed mode at high fields. This evolvement has been paralleled with pulsed energy storage coil development and testing from tens of kJ at low fields to a 20 MJ prototype tokamak induction coil at 7.5 T. Energy transfer times have ranged from 0.7 ms to several seconds. Electric utility magnetic storage for prospective application is for diurnal load leveling with massive systems to store 10 GWh at 1.8 K in a dewar structure supported on bedrock underground. An immediate utility application is a 30 MJ system to be used to damp power oscillations on the Bonneville Power Administration electric transmission lines. An off-shoot of this last work is a new program for electric utility VAR control with the potential for use to suppress subsynchronous resonance. This paper presents work in progress, work planned, and recently completed unusual work
Energy storage: potential analysis is still on the way

International Nuclear Information System (INIS)

Signoret, Stephane; Dejeu, Mathieu; Deschaseaux, Christelle; De Santis, Audrey; Cygler, Clement; Petitot, Pauline

2014-01-01

A set of articles gives an overview of the status and current evolutions of the energy storage sector. The different technologies (flywheel, lithium-ion batteries, NaS or Zebra batteries, compressed air energy storage or CAES, 2. generation CAES, pump storage power plants or PSP) have different applications areas, and also different technological maturity levels. PSPs have probably the best potential nowadays, but investors must be supported. In an interview, a member of the CNRS evokes the main researches, the obstacles in the development of solar thermodynamic plants, technology transfers, and the potential of hydrogen for massive energy storage. An article outlines the need to develop the battery market. Several technological examples and experiments are then presented: Nice Grid (storage at the source level), FlyProd (energy storage by flywheel). An article then addresses the issue of heat storage, notably in a situation of energy co-generation. Researches and prototype development are then presented, the objective of which is to obtain an adiabatic CAES. The last articles address the development of hydrogen to store energy (technologies) and a first technological demonstrator
Methodology for the economic optimisation of energy storage systems for frequency support in wind power plants

International Nuclear Information System (INIS)

Johnston, Lewis; Díaz-González, Francisco; Gomis-Bellmunt, Oriol; Corchero-García, Cristina; Cruz-Zambrano, Miguel

2015-01-01

Highlights: • Optimisation of energy storage system with wind power plant for frequency response. • Energy storage option considered could be economically viable. • For a 50 MW wind farm, an energy storage system of 5.3 MW and 3 MW h was found. - Abstract: This paper proposes a methodology for the economic optimisation of the sizing of Energy Storage Systems (ESSs) whilst enhancing the participation of Wind Power Plants (WPP) in network primary frequency control support. The methodology was designed flexibly, so it can be applied to different energy markets and to include different ESS technologies. The methodology includes the formulation and solving of a Linear Programming (LP) problem. The methodology was applied to the particular case of a 50 MW WPP, equipped with a Vanadium Redox Flow battery (VRB) in the UK energy market. Analysis is performed considering real data on the UK regular energy market and the UK frequency response market. Data for wind power generation and energy storage costs are estimated from literature. Results suggest that, under certain assumptions, ESSs can be profitable for the operator of a WPP that is providing frequency response. The ESS provides power reserves such that the WPP can generate close to the maximum energy available. The solution of the optimisation problem establishes that an ESS with a power rating of 5.3 MW and energy capacity of about 3 MW h would be enough to provide such service whilst maximising the incomes for the WPP operator considering the regular and frequency regulation UK markets
Federal Tax Incentives for Energy Storage Systems

Energy Technology Data Exchange (ETDEWEB)

Anderson, Katherine H [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Elgqvist, Emma M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Settle, Donald E [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-01-16

Investments in renewable energy are more attractive due to the contribution of two key federal tax incentives. The investment tax credit (ITC) and the Modified Accelerated Cost Recovery System (MACRS) depreciation deduction may apply to energy storage systems such as batteries depending on who owns the battery and how the battery is used. The guidelines in this fact sheet apply to energy storage systems installed at the same time as the renewable energy system.
A Method of Dynamic Extended Reactive Power Optimization in Distribution Network Containing Photovoltaic-Storage System

Science.gov (United States)

Wang, Wu; Huang, Wei; Zhang, Yongjun

2018-03-01

The grid-integration of Photovoltaic-Storage System brings some undefined factors to the network. In order to make full use of the adjusting ability of Photovoltaic-Storage System (PSS), this paper puts forward a reactive power optimization model, which are used to construct the objective function based on power loss and the device adjusting cost, including energy storage adjusting cost. By using Cataclysmic Genetic Algorithm to solve this optimization problem, and comparing with other optimization method, the result proved that: the method of dynamic extended reactive power optimization this article puts forward, can enhance the effect of reactive power optimization, including reducing power loss and device adjusting cost, meanwhile, it gives consideration to the safety of voltage.
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
Implementation and Performance Evaluation of Distributed Cloud Storage Solutions using Random Linear Network Coding

DEFF Research Database (Denmark)

Fitzek, Frank; Toth, Tamas; Szabados, Áron

2014-01-01

This paper advocates the use of random linear network coding for storage in distributed clouds in order to reduce storage and traffic costs in dynamic settings, i.e. when adding and removing numerous storage devices/clouds on-the-fly and when the number of reachable clouds is limited. We introduce...... various network coding approaches that trade-off reliability, storage and traffic costs, and system complexity relying on probabilistic recoding for cloud regeneration. We compare these approaches with other approaches based on data replication and Reed-Solomon codes. A simulator has been developed...... to carry out a thorough performance evaluation of the various approaches when relying on different system settings, e.g., finite fields, and network/storage conditions, e.g., storage space used per cloud, limited network use, and limited recoding capabilities. In contrast to standard coding approaches, our...

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.
High to ultra-high power electrical energy storage.

Science.gov (United States)

Sherrill, Stefanie A; Banerjee, Parag; Rubloff, Gary W; Lee, Sang Bok

2011-12-14

High power electrical energy storage systems are becoming critical devices for advanced energy storage technology. This is true in part due to their high rate capabilities and moderate energy densities which allow them to capture power efficiently from evanescent, renewable energy sources. High power systems include both electrochemical capacitors and electrostatic capacitors. These devices have fast charging and discharging rates, supplying energy within seconds or less. Recent research has focused on increasing power and energy density of the devices using advanced materials and novel architectural design. An increase in understanding of structure-property relationships in nanomaterials and interfaces and the ability to control nanostructures precisely has led to an immense improvement in the performance characteristics of these devices. In this review, we discuss the recent advances for both electrochemical and electrostatic capacitors as high power electrical energy storage systems, and propose directions and challenges for the future. We asses the opportunities in nanostructure-based high power electrical energy storage devices and include electrochemical and electrostatic capacitors for their potential to open the door to a new regime of power energy.
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.
Reaction wheels for kinetic energy storage

Science.gov (United States)

Studer, P. A.

1984-11-01

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.
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
Compressed Air Energy Storage in Denmark

DEFF Research Database (Denmark)

Salgi, Georges Garabeth; Lund, Henrik

2006-01-01

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......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...
Entropy, pumped-storage and energy system finance

Science.gov (United States)

Karakatsanis, Georgios

2015-04-01

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

Science.gov (United States)

Calle, Carlos I.; Mackey, Paul J.; Johansen, Michael R.; Phillips, James, III; Hogue, Michael; Kaner, Richard B.; El-Kady, Maher

2016-01-01

Development of graphene-based energy storage devices based on the Laser Scribe system developed by the University of California Los Angeles. These devices These graphene-based devices store charge on graphene sheets and take advantage of the large accessible surface area of graphene (2,600 m2g) to increase the electrical energy that can be stored. The proposed devices should have the electrical storage capacity of thin-film-ion batteries but with much shorter charge discharge cycle times as well as longer lives The proposed devices will be carbon-based and so will not have the same issues with flammability or toxicity as the standard lithium-based storage cells.
Outlook and application analysis of energy storage in power system with high renewable energy penetration

Science.gov (United States)

Feng, Junshu; Zhang, Fuqiang

2018-02-01

To realize low-emission and low-carbon energy production and consumption, large-scale development and utilization of renewable energy has been put into practice in China. And it has been recognized that power system of future high renewable energy shares can operate more reliably with the participation of energy storage. Considering the significant role of storage playing in the future power system, this paper focuses on the application of energy storage with high renewable energy penetration. Firstly, two application modes are given, including demand side application mode and centralized renewable energy farm application mode. Afterwards, a high renewable energy penetration scenario of northwest region in China is designed, and its production simulation with application of energy storage in 2050 has been calculated and analysed. Finally, a development path and outlook of energy storage is given.
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...
Stationary battery storage of energy transition a central component; Stationaere Batteriespeicher der Energiewende eine zentrale Komponente

Energy Technology Data Exchange (ETDEWEB)

Vetter, Matthias; Lux, Stephan [Fraunhofer-Institut fuer Solare Energiesysteme ISE, Freiburg (Germany)

2017-01-15

In a regenerative energy system with strong fluctuations in electricity production, the importance of short-term storage is increasing - on the one hand, in order to optimal need-oriented use of the energy supply, on the other hand, at any time to ensure a high network quality. The present overview of stationary battery storage shows how important it will be especially in the area of larger storage facilities with direct link to regenerative power plants, as a district storage or in the industry. [German] In einem regenerativen Energiesystem mit starken Fluktuationen der Stromproduktion nimmt die Bedeutung der Kurzzeitspeicherung zu - einerseits, um das Energieangebot bedarfsgerecht optimal zu nutzen, andererseits, um zu jedem Zeitpunkt eine hohe Netzqualitaet zu gewaehrleisten. Der vorliegende Ueberblick ueber stationaere Batteriespeicher zeigt, wie wichtig vor allem der Bereich groesserer Speicher in direkter Koppelung mit regenerativen Kraftwerken, als Quartiersspeicher oder im Gewerbe sein wird.
Identification of energy storage rate components. Theoretical and experimental approach

International Nuclear Information System (INIS)

Oliferuk, W; Maj, M

2010-01-01

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.
Heat storage. Role in the energy system of the future

International Nuclear Information System (INIS)

Hauer, Andreas; Woerner, Antje; Kranz, Stefan; Schumacher, Patrick; Gschwander, Stefan; Appen, Jan von; Hidalgo, Diego; Gross, Bodo; Grashof, Katherina

2015-01-01

For the implementation of the energy transition in Germany can contribute in a variety of applications thermal energy storage. Both at the integration of renewable energy sources, as well as in increasing the energy efficiency in the building sector and industry can utilize heat and cold storage great potential. For this diverse storage technologies are available. In Germany numerous research and development projects are running currently, covering the broad possibilities of thermal energy storage. [de
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 conventi......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...
Hydrogen energy network start-up scenario

International Nuclear Information System (INIS)

Weingartner, S.; Ellerbrock, H.

1994-01-01

Hydrogen is widely discussed as future fuel and energy storage medium either to replace conventional fuels for automobiles, aircrafts and ships or to avoid the necessity of bulky battery systems for electricity storage, especially in connection with solar power systems. These discussions however started more than 25 years ago and up to now hydrogen has failed to achieve a major break-through towards wider application as energy storage medium in civil markets. The main reason is that other fuels are cheaper and very well implemented in our daily life. A study has been performed at Deutsche Aerospace in order to evaluate the boundary conditions, either political or economical, which would give hydrogen the necessary push, i.e. advantage over conventional fuels. The main goal of this study was to identify critical influence factors and specific start-up scenarios which would allow an economical and practically realistic use of hydrogen as fuel and energy medium in certain niche markets outside the space industry. Method and major results of this study are presented in detail in the paper. Certain niche markets could be identified, where with little initial governmental support, either by funding, tax laws or legislation, hydrogen can compete with conventional fuels. This however requires a scenario where a lot of small actions have to be taken by a high variety of institutions and industries which today are not interconnected with each other, i.e. it requires a new cooperative and proactive network between e.g. energy utilities, car industries, those who have a sound experience with hydrogen (space industry, chemical industry) and last, but certainly not the least, the government. Based on the developed scenario precise recommendations are drawn as conclusions
Lightweight storage and overlay networks for fault tolerance.

Energy Technology Data Exchange (ETDEWEB)

Oldfield, Ron A.

2010-01-01

The next generation of capability-class, massively parallel processing (MPP) systems is expected to have hundreds of thousands to millions of processors, In such environments, it is critical to have fault-tolerance mechanisms, including checkpoint/restart, that scale with the size of applications and the percentage of the system on which the applications execute. For application-driven, periodic checkpoint operations, the state-of-the-art does not provide a scalable solution. For example, on today's massive-scale systems that execute applications which consume most of the memory of the employed compute nodes, checkpoint operations generate I/O that consumes nearly 80% of the total I/O usage. Motivated by this observation, this project aims to improve I/O performance for application-directed checkpoints through the use of lightweight storage architectures and overlay networks. Lightweight storage provide direct access to underlying storage devices. Overlay networks provide caching and processing capabilities in the compute-node fabric. The combination has potential to signifcantly reduce I/O overhead for large-scale applications. This report describes our combined efforts to model and understand overheads for application-directed checkpoints, as well as implementation and performance analysis of a checkpoint service that uses available compute nodes as a network cache for checkpoint operations.
Modular Energy Storage System for Alternative Energy Vehicles

Energy Technology Data Exchange (ETDEWEB)

Thomas, Janice [Magna Electronics Inc., Auburn Hills, MI (United States); Ervin, Frank [Magna Electronics Inc., Auburn Hills, MI (United States)

2012-05-15

An electrical vehicle environment was established to promote research and technology development in the area of high power energy management. The project incorporates a topology that permits parallel development of an alternative energy delivery system and an energy storage system. The objective of the project is to develop technologies, specifically power electronics, energy storage electronics and controls that provide efficient and effective energy management between electrically powered devices in alternative energy vehicles plugin electric vehicles, hybrid vehicles, range extended vehicles, and hydrogen-based fuel cell vehicles. In order to meet the project objectives, the Vehicle Energy Management System (VEMS) was defined and subsystem requirements were obtained. Afterwards, power electronics, energy storage electronics and controls were designed. Finally, these subsystems were built, tested individually, and integrated into an electric vehicle system to evaluate and optimize the subsystems performance. Phase 1 of the program established the fundamental test bed to support development of an electrical environment ideal for fuel cell application and the mitigation of many shortcomings of current fuel cell technology. Phase 2, continued development from Phase 1, focusing on implementing subsystem requirements, design and construction of the energy management subsystem, and the integration of this subsystem into the surrogate electric vehicle. Phase 2 also required the development of an Alternative Energy System (AES) capable of emulating electrical characteristics of fuel cells, battery, gen set, etc. Under the scope of the project, a boost converter that couples the alternate energy delivery system to the energy storage system was developed, constructed and tested. Modeling tools were utilized during the design process to optimize both component and system design. This model driven design process enabled an iterative process to track and evaluate the impact
Superconducting Magnetic Energy Storage

International Nuclear Information System (INIS)

Hassenzahl, W.

1989-01-01

Recent programmatic developments in Superconducting Magnetic Energy Storage (SMES) have prompted renewed and widespread interest in this field. In mid 1987 the Defense Nuclear Agency, acting for the Strategic Defense Initiative Office issued a request for proposals for the design and construction of SMES Engineering Test Model (ETM). Two teams, one led by Bechtel and the other by Ebasco, are now engaged in the first phase of the development of a 10 to 20 MWhr ETM. This report presents the rationale for energy storage on utility systems, describes the general technology of SMES, and explains the chronological development of the technology. The present ETM program is outlined; details of the two projects for ETM development are described in other papers in these proceedings. The impact of high Tc materials on SMES is discussed
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 heat transfer. The system model was used to conduct sensitivity analysis, baseline performance, and levelized cost of 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
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.

Redox-active Hybrid Materials for Pseudocapacitive Energy Storage

Science.gov (United States)

Boota, Muhammad

Organic-inorganic hybrid materials show a great promise for the purpose of manufacturing high performance electrode materials for electrochemical energy storage systems and beyond. Molecular level combination of two best suited components in a hybrid material leads to new or sometimes exceptional sets of physical, chemical, mechanical and electrochemical properties that makes them attractive for broad ranges of applications. Recently, there has been growing interest in producing redox-active hybrid nanomaterials for energy storage applications where generally the organic component provides high redox capacitance and the inorganic component offers high conductivity and robust support. While organic-inorganic hybrid materials offer tremendous opportunities for electrochemical energy storage applications, the task of matching the right organic material out of hundreds of natural and nearly unlimited synthetic organic molecules to appropriate nanostructured inorganic support hampers their electrochemical energy storage applications. We aim to present the recent development of redox-active hybrid materials for pseudocapacitive energy storage. We will show the impact of combination of suitable organic materials with distinct carbon nanostructures and/or highly conductive metal carbides (MXenes) on conductivity, charge storage performance, and cyclability. Combined experimental and molecular simulation results will be discussed to shed light on the interfacial organic-inorganic interactions, pseudocapacitive charge storage mechanisms, and likely orientations of organic molecules on conductive supports. Later, the concept of all-pseudocapacitive organic-inorganic asymmetric supercapacitors will be highlighted which open up new avenues for developing inexpensive, sustainable, and high energy density aqueous supercapacitors. Lastly, future challenges and opportunities to further tailor the redox-active hybrids will be highlighted.
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
Carbon nanomaterials for advanced energy conversion and storage.

Science.gov (United States)

Dai, Liming; Chang, Dong Wook; Baek, Jong-Beom; Lu, Wen

2012-04-23

It is estimated that the world will need to double its energy supply by 2050. Nanotechnology has opened up new frontiers in materials science and engineering to meet this challenge by creating new materials, particularly carbon nanomaterials, for efficient energy conversion and storage. Comparing to conventional energy materials, carbon nanomaterials possess unique size-/surface-dependent (e.g., morphological, electrical, optical, and mechanical) properties useful for enhancing the energy-conversion and storage performances. During the past 25 years or so, therefore, considerable efforts have been made to utilize the unique properties of carbon nanomaterials, including fullerenes, carbon nanotubes, and graphene, as energy materials, and tremendous progress has been achieved in developing high-performance energy conversion (e.g., solar cells and fuel cells) and storage (e.g., supercapacitors and batteries) devices. This article reviews progress in the research and development of carbon nanomaterials during the past twenty years or so for advanced energy conversion and storage, along with some discussions on challenges and perspectives in this exciting field. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
A Comparative Study on Substation Types and Network Layouts in Connection with Low-Energy District Heating Systems

DEFF Research Database (Denmark)

Tol, Hakan; Svendsen, Svend

2012-01-01

The study deals with low-energy district heating (DH) networks operating in low temperatures such as 55 °C in terms of supply and 25 °C in terms of return. The network layout, additional booster pumps, and different substation types such as storage tanks either equipped or not equipped in domesti...... for end-consumers were also studied, heat loss from these networks and the drop in temperature in the heat-carrier-supply medium being compared.......The study deals with low-energy district heating (DH) networks operating in low temperatures such as 55 °C in terms of supply and 25 °C in terms of return. The network layout, additional booster pumps, and different substation types such as storage tanks either equipped or not equipped in domestic...... hot water production site were examined. Effects of booster pumps on pipe dimensions in the latter case were investigated. Temperature drops during the summer months due to low heat demands of consumers were explored. Use of approaches such as looped networks and branched network layouts with bypasses...
Energy storage. Stakes, technical solutions and valorization opportunities

International Nuclear Information System (INIS)

2012-03-01

As a key factor to allow the continuous growth of renewable energies, energy storage technologies are now more than ever in the spotlight. In order to grasp the stakes, understand the technology diversity, learn relevant orders of magnitudes and comprehend the close intricacy of energy storage with energy and environmental issues, ENEA has published a detailed and well-documented publication on the subject
Energy Storage of Polyarylene Ether Nitriles at High Temperature

Science.gov (United States)

Tang, Xiaohe; You, Yong; Mao, Hua; Li, Kui; Wei, Renbo; Liu, Xiaobo

2018-03-01

Polyarylene ether nitrile (PEN) was synthesized and used as film capacitors for energy storage at high temperature. Scanning electron microscopy observation indicated that the films of PEN have pinholes at nanoscales which restricted the energy storage properties of the material. The pinhole shadowing effect through which the energy storage properties of PEN were effectively improved to be 2.3 J/cm3 was observed by using the overlapped film of PEN. The high glass transition temperature (T g) of PEN was as high as 216 °C and PEN film showed stable dielectric constant, breakdown strength and energy storage density before the T g. The PEN films will be a potential candidate as high performance electronic storage materials used at high temperature.
Energy Efficient Digital Networks

Energy Technology Data Exchange (ETDEWEB)

Lanzisera, Steven [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Brown, Richard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2013-01-01

Digital networks are the foundation of the information services, and play an expanding and indispensable role in our lives, via the Internet, email, mobile phones, etc. However, these networks consume energy, both through the direct energy use of the network interfaces and equipment that comprise the network, and in the effect they have on the operating patterns of devices connected to the network. The purpose of this research was to investigate a variety of technology and policy issues related to the energy use caused by digital networks, and to further develop several energy-efficiency technologies targeted at networks.
Energy storage cell impedance measuring apparatus, methods and related systems

Science.gov (United States)

Morrison, John L.; Morrison, William H.; Christophersen, Jon P.

2017-12-26

Energy storage cell impedance testing devices, circuits, and related methods are disclosed. An energy storage cell impedance measuring device includes a sum of sinusoids (SOS) current excitation circuit including differential current sources configured to isolate a ground terminal of the differential current sources from a positive terminal and a negative terminal of an energy storage cell. A method includes applying an SOS signal comprising a sum of sinusoidal current signals to the energy storage cell with the SOS current excitation circuit, each of the sinusoidal current signals oscillating at a different one of a plurality of different frequencies. The method also includes measuring an electrical signal at a positive terminal and a negative terminal of the energy storage cell, and computing an impedance of the energy storage cell at each of the plurality of different frequencies using the measured electrical signal.
Feed-in tariffs for promotion of energy storage technologies

Energy Technology Data Exchange (ETDEWEB)

Krajacic, Goran, E-mail: Goran.Krajacic@fsb.h [University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture, Ivana Lucica 5, 10002 Zagreb (Croatia); Duic, Neven, E-mail: Neven.Duic@fsb.h [University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture, Ivana Lucica 5, 10002 Zagreb (Croatia); Instituto Superior Tecnico, Lisbon (Portugal); Tsikalakis, Antonis, E-mail: atsikal@corfu.power.ece.ntua.g [National Technical University of Athens, Athens (Greece); Zoulias, Manos, E-mail: mzoulias@cres.g [Centre for Renewable Energy Sources and Savings (CRES), Pikermi (Greece); Caralis, George, E-mail: gcaralis@central.ntua.g [National Technical University of Athens, Athens (Greece); Panteri, Eirini, E-mail: panteri@rae.g [Regulatory Authority for Energy (RAE), Athens (Greece); Carvalho, Maria da Graca, E-mail: mariadagraca.carvalho@europarl.europa.e [Instituto Superior Tecnico, Lisbon (Portugal)

2011-03-15

Faster market integration of new energy technologies can be achieved by use of proper support mechanisms that will create favourable market conditions for such technologies. The best examples of support mechanisms presented in the last two decades have been the various schemes for the promotion of renewable energy sources (RES). In the EU, the most successful supporting schemes are feed-in tariffs which have significantly increased utilisation of renewable energy sources in Germany, Spain, Portugal, Denmark and many other EU countries. Despite the successful feed-in tariffs for RES promotion, in many cases RES penetration is limited by power system requirements linked to the intermittency of RES sources and technical capabilities of grids. These problems can be solved by implementation of energy storage technologies like reversible or pumped hydro, hydrogen, batteries or any other technology that can be used for balancing or dump load. In this paper, feed-in tariffs for various energy storage technologies are discussed along with a proposal for their application in more appropriate regions. After successful application on islands and outermost regions, energy storage tariffs should be also applied in mainland power systems. Increased use of energy storage could optimise existing assets on the market. - Research highlights: {yields} Feed-in tariffs will promote development and use of energy storage technologies. {yields} Energy storage effectively increases RES penetration. {yields} Pumped Hydro Storage: an efficient solution for RES integration in islands. {yields} Remuneration of Batteries and Inverters as a service can increase RES Penetration. {yields} Desalination, apart from water can help in more efficient RES integration.
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)
Characterization and assessment of novel bulk storage technologies : a study for the DOE Energy Storage Systems program.

Energy Technology Data Exchange (ETDEWEB)

Huff, Georgianne; Tong, Nellie (KEMA Consulting, Fairfax, VA); Fioravanti, Richard (KEMA Consulting, Fairfax, VA); Gordon, Paul (Sentech/SRA International, Bethesda, MD); Markel, Larry (Sentech/SRA International, Bethesda, MD); Agrawal, Poonum (Sentech/SRA International, Bethesda, MD); Nourai, Ali (KEMA Consulting, Fairfax, VA)

2011-04-01

This paper reports the results of a high-level study to assess the technological readiness and technical and economic feasibility of 17 novel bulk energy storage technologies. The novel technologies assessed were variations of either pumped storage hydropower (PSH) or compressed air energy storage (CAES). The report also identifies major technological gaps and barriers to the commercialization of each technology. Recommendations as to where future R&D efforts for the various technologies are also provided based on each technology's technological readiness and the expected time to commercialization (short, medium, or long term). The U.S. Department of Energy (DOE) commissioned this assessment of novel concepts in large-scale energy storage to aid in future program planning of its Energy Storage Program. The intent of the study is to determine if any new but still unproven bulk energy storage concepts merit government support to investigate their technical and economic feasibility or to speed their commercialization. The study focuses on compressed air energy storage (CAES) and pumped storage hydropower (PSH). It identifies relevant applications for bulk storage, defines the associated technical requirements, characterizes and assesses the feasibility of the proposed new concepts to address these requirements, identifies gaps and barriers, and recommends the type of government support and research and development (R&D) needed to accelerate the commercialization of these technologies.
Sustainability index approach as a selection criteria for energy storage system of an intermittent renewable energy source

International Nuclear Information System (INIS)

Raza, Syed Shabbar; Janajreh, Isam; Ghenai, Chaouki

2014-01-01

Highlights: • Three renewable energy storage options considered: lead acid and lithium polymer batteries and fuel cell. • Hydrogen fuel cell system is the most feasible energy storage option for the long term energy storage. • Sustainability index approach is a novel method used to quantify the qualitative properties of the system. - Abstract: The sustainability index is an adaptive, multicriteria and novel technique that is used to compare different energy storage systems for their sustainability. This innovative concept utilizes both qualitative and quantitative results to measure sustainability through an index based approach. This report aims to compare three different energy storage options for an intermittent renewable energy source. The three energy storage options are lead acid batteries, lithium polymer batteries and fuel cell systems, that are selected due to their availability and the geographical constrain of using other energy storage options. The renewable energy source used is solar photovoltaic (PV). Several technical, economic and environmental factors have been discussed elaborately which would help us to evaluate the merits of the energy storage system for long term storage. Finally, a novel sustainability index has been proposed which quantifies the qualitative and quantitative aspects of the factors discussed, and thus helps us choose the ideal energy storage system for our scenario. A weighted sum approach is used to quantify each factor according to their importance. After a detailed analysis of the three energy storage systems through the sustainability index approach, the most feasible energy storage option was found to be fuel cell systems which can provide a long term energy storage option and also environmental friendly
Quantifying induced effects of subsurface renewable energy storage

Science.gov (United States)

Bauer, Sebastian; Beyer, Christof; Pfeiffer, Tilmann; Boockmeyer, Anke; Popp, Steffi; Delfs, Jens-Olaf; Wang, Bo; Li, Dedong; Dethlefsen, Frank; Dahmke, Andreas

2015-04-01

New methods and technologies for energy storage are required for the transition to renewable energy sources. Subsurface energy storage systems such as salt caverns or porous formations offer the possibility of hosting large amounts of energy or substance. When employing these systems, an adequate system and process understanding is required in order to assess the feasibility of the individual storage option at the respective site and to predict the complex and interacting effects induced. This understanding is the basis for assessing the potential as well as the risks connected with a sustainable usage of these storage options, especially when considering possible mutual influences. For achieving this aim, in this work synthetic scenarios for the use of the geological underground as an energy storage system are developed and parameterized. The scenarios are designed to represent typical conditions in North Germany. The types of subsurface use investigated here include gas storage and heat storage in porous formations. The scenarios are numerically simulated and interpreted with regard to risk analysis and effect forecasting. For this, the numerical simulators Eclipse and OpenGeoSys are used. The latter is enhanced to include the required coupled hydraulic, thermal, geomechanical and geochemical processes. Using the simulated and interpreted scenarios, the induced effects are quantified individually and monitoring concepts for observing these effects are derived. This presentation will detail the general investigation concept used and analyze the parameter availability for this type of model applications. Then the process implementation and numerical methods required and applied for simulating the induced effects of subsurface storage are detailed and explained. Application examples show the developed methods and quantify induced effects and storage sizes for the typical settings parameterized. This work is part of the ANGUS+ project, funded by the German Ministry
Recent Advances in Porous Carbon Materials for Electrochemical Energy Storage.

Science.gov (United States)

Wang, Libin; Hu, Xianluo

2018-06-18

Climate change and the energy crisis have promoted the rapid development of electrochemical energy-storage devices. Owing to many intriguing physicochemical properties, such as excellent chemical stability, high electronic conductivity, and a large specific surface area, porous carbon materials have always been considering as a promising candidate for electrochemical energy storage. To date, a wide variety of porous carbon materials based upon molecular design, pore control, and compositional tailoring have been proposed for energy-storage applications. This focus review summarizes recent advances in the synthesis of various porous carbon materials from the view of energy storage, particularly in the past three years. Their applications in representative electrochemical energy-storage devices, such as lithium-ion batteries, supercapacitors, and lithium-ion hybrid capacitors, are discussed in this review, with a look forward to offer some inspiration and guidelines for the exploitation of advanced carbon-based energy-storage materials. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Workshop on environmental and energy applications of neural networks

Energy Technology Data Exchange (ETDEWEB)

Hashem, S.

1995-03-01

This report consists of the abstracts for the papers given at the conference. Applications of neural networks in the environmental, energy and biomedical fields are discussed. Some of the topics covered are: predicting atmospheric pollutant concentrations due to fossil-fired electric power generation; hazardous waste characterization; nondestructive TRU (transuranic) waste assay; risk analysis; load forecasting for electric utilities; design of a wind power storage and generation system; nuclear fuel management; etc.
Workshop on environmental and energy applications of neural networks

International Nuclear Information System (INIS)

Hashem, S.

1995-03-01

This report consists of the abstracts for the papers given at the conference. Applications of neural networks in the environmental, energy and biomedical fields are discussed. Some of the topics covered are: predicting atmospheric pollutant concentrations due to fossil-fired electric power generation; hazardous waste characterization; nondestructive TRU (transuranic) waste assay; risk analysis; load forecasting for electric utilities; design of a wind power storage and generation system; nuclear fuel management; etc
Characterisation of electrical energy storage technologies

NARCIS (Netherlands)

Lopes Ferreira, H.M.; Garde, R.; Fulli, G.; Kling, W.L.; Pecas Lopes, J.

2013-01-01

In the current situation with the unprecedented deployment of clean technologies for electricity generation, it is natural to expect that storage will play an important role in electricity networks. This paper provides a qualitative methodology to select the appropriate technology or mix of
Kinetic energy storage of off-peak electricity

International Nuclear Information System (INIS)

Simpson, L.A.; Oldaker, I.E.; Stermscheg, J.

1975-09-01

The concept of using large flywheels to store off-peak electricity has been considered. The development of high strength composite materials has made possible improvements in the energy storage capacity of such devices. The problems involved in designing large flywheels and their economic advantages over alternative means of energy storage are discussed. The economic arguments are based on the present or near future capabilities and costs of structural composite materials. The flywheel costs turn out to be considerably higher than for many alternative schemes including advanced batteries, gas turbine generators and pumped storage schemes. (author)
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.
Aquifer thermal energy storage in Finland

Energy Technology Data Exchange (ETDEWEB)

Iihola, H; Ala-Peijari, T; Seppaenen, H

1988-01-01

The rapid changes and crises in the field of energy during the 1970s and 1980s have forced us to examine the use of energy more critically and to look for new ideas. Seasonal aquifer thermal energy storage (T < 100/sup 0/C) on a large scale is one of the grey areas which have not yet been extensively explored. However, projects are currently underway in a dozen countries. In Finland there have been three demonstration projects from 1974 to 1987. International co-operation under the auspices of the International Energy Agency, Annex VI, 'Environmental and Chemical Aspects of Thermal Energy Storage in Aquifers and Research and Development of Water Treatment Methods' started in 1987. The research being undertaken in 8 countries includes several elements fundamental to hydrochemistry and biochemistry.

Multifunctional Structures for High-Energy Lightweight Load-Bearing Storage

Science.gov (United States)

Loyselle, Patricia L.

2018-01-01

This is a pull-up banner of the Multifunctional Structures for High-Energy Lightweight Load-bearing Storage (M-SHELLS) technology that will be on display at the SciTech Conference in January 2018. Efforts in Multifunctional Structures for High Energy Load-Bearing Storage (M-Shells) are pushing the boundaries of development for hybrid electric propulsion for future commercial aeronautical transport. The M-Shells hybrid material would serve as the power/energy storage of the vehicle and provide structural integrity, freeing up usable volume and mass typically occupied by bulky batteries. The ultimate goal is to demonstrate a system-level mass savings with a multifunctional structure with energy storage.
Localization of Energy Harvesting Empowered Underwater Optical Wireless Sensor Networks

KAUST Repository

Saeed, Nasir

2017-12-20

In this paper, a received signal strength (RSS) based localization technique is developed for energy harvesting underwater optical wireless sensor networks (EH-UOWSNs), where the optical noise sources and channel impairments of seawater pose significant challenges for range estimation. Energy limitation is another major problem due to the limited battery power and difficulty in replacing or recharging the battery of an underwater sensor node. In the proposed framework, sensor nodes with insufficient battery, harvest the energy and starts communicating once it has sufficient energy storage. Network localization is carried out by measuring the RSSs of active nodes, which are modeled based on the underwater optical communication channel characteristics. Thereafter, block kernel matrices are computed for the RSS based range measurements. Unlike the traditional shortest-path approach, the proposed technique reduces the shortest path estimation for each block kernel matrix. Once the complete block kernel matrices are available, a closed form localization technique is developed to find the location of every optical sensor node in the network. Furthermore, an analytical expression for Cramer Rao lower bound (CRLB) is derived as a benchmark to compare the localization performance of the proposed technique. Finally, extensive simulations show that the proposed technique outperforms the well-known network localization techniques.
Pulsed power generators using an inductive energy storage system

International Nuclear Information System (INIS)

Akiyama, H.; Sueda, T.; Katschinski, U.; Katsuki, S.; Maeda, S.

1996-01-01

The pulsed power generators using an inductive energy storage system are extremely compact and lightweight in comparison with those using a capacitive energy storage system. The reliable and repetitively operated opening switch is necessary to realize the inductive pulsed power generator. Here, the pulsed power generators using the inductive energy storage system, which have been developed in Kumamoto University, are summarized. copyright 1996 American Institute of Physics
Considerations on the need for electricity storage requirements: Power versus energy

International Nuclear Information System (INIS)

Belderbos, Andreas; Virag, Ana; D’haeseleer, William; Delarue, Erik

2017-01-01

Highlights: • General storage principles are analyzed. • Storage units have different limitations (power versus energy). • Storage power and energy are required, dependent on residual profile. • Relationship between residual profile and optimal storage portfolio is derived. • Broadly applicable rules regarding optimal storage investments are presented. - Abstract: Different storage technologies enable an increasing share of variable renewable generation in the electricity system by reducing the temporal mismatch between generation and demand. Two storage ratings are essential to time-shift delivery of electricity to loads: electric power, or instantaneous electricity flow [W], and electric energy, or power integrated over time [Wh]. An optimal storage portfolio is likely composed of multiple technologies, each having specific power and energy ratings. This paper derives and explains the link between the shape of the time-varying demand and generation profiles and the amount of desirably installed storage capacity, both energy and power. An analysis is performed for individual storage technologies first, showing a link between the necessary power and energy capacity and the demand and generation profile. Then combinations of storage technologies are analyzed to reveal their mutual interaction in a storage portfolio. Results show an increase in desirability for storage technologies with low cost power ratings when the mismatch between generation and demand occurs in daily to weekly cycles. Storage technologies with low cost energy ratings are preferred when this mismatch occurs in monthly to seasonal cycles. The findings of this work can help energy system planners and policy makers to explain results from generation expansion planning studies and to isolate the storage benefits accountable to temporal arbitrage in broader electricity storage studies.
Using energy storage for strategic advantage in competitive electricity markets

International Nuclear Information System (INIS)

Hurwitch, J.W.; Symons, P.

1998-01-01

Energy storage products are emerging for use in power quality, electric transmission and distribution, and renewable energy applications. Despite this emergence into high-value markets, widespread market penetration will only occur when the value of the services that energy storage products can deliver are clearly delineated. The emergence of competitive electricity markets will more clearly define the flexible benefits of energy storage devices. This paper presents a summary of the ESA's position of the status of energy storage technologies, the market barriers, and steps the ESA is undertaking to reduce these barriers. (author)
Hybrid Electric Energy Storages: Their Specific Features and Application (Review)

Science.gov (United States)

Popel', O. S.; Tarasenko, A. B.

2018-05-01

The article presents a review of various aspects related to development and practical use of hybrid electric energy storages (i.e., those uniting different energy storage technologies and devices in an integrated system) in transport and conventional and renewable power engineering applications. Such devices, which were initially developed for transport power installations, are increasingly being used by other consumers characterized by pronounced nonuniformities of their load schedule. A range of tasks solved using such energy storages is considered. It is shown that, owing to the advent of new types of energy storages and the extended spectrum of their performance characteristics, new possibilities for combining different types of energy storages and for developing hybrid systems have become available. This, in turn, opens up the possibility of making energy storages with better mass and dimension characteristics and achieving essentially lower operational costs. The possibility to secure more comfortable (base) operating modes of primary sources of energy (heat engines and renewable energy source based power installations) and to achieve a higher capacity utilization factor are unquestionable merits of hybrid energy storages. Development of optimal process circuit solutions, as well as energy conversion and control devices facilitating the fullest utilization of the properties of each individual energy storage included in the hybrid system, is among the important lines of research carried out in this field in Russia and abroad. Our review of existing developments has shown that there are no universal technical solutions in this field (the specific features of a consumer have an essential effect on the process circuit solutions and on the composition of a hybrid energy storage), a circumstance that dictates the need to extend the scope of investigations in this promising field.
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.
Multifunctional Composites for Future Energy Storage in Aerospace Structures

Directory of Open Access Journals (Sweden)

Till Julian Adam

2018-02-01

Full Text Available Multifunctionalization of fiber-reinforced composites, especially by adding energy storage capabilities, is a promising approach to realize lightweight structural energy storages for future transport vehicles. Compared to conventional energy storage systems, energy density can be increased by reducing parasitic masses of non-energy-storing components and by benefitting from the composite meso- and microarchitectures. In this paper, the most relevant existing approaches towards multifunctional energy storages are reviewed and subdivided into five groups by distinguishing their degree of integration and their scale of multifunctionalization. By introducing a modified range equation for battery-powered electric aircrafts, possible range extensions enabled by multifunctionalization are estimated. Furthermore, general and aerospace specific potentials of multifunctional energy storages are discussed. Representing an intermediate degree of structural integration, experimental results for a multifunctional energy-storing glass fiber-reinforced composite based on the ceramic electrolyte Li1.4Al0.4Ti1.6(PO43 are presented. Cyclic voltammetry tests are used to characterize the double-layer behavior combined with galvanostatic charge–discharge measurements for capacitance calculation. The capacitance is observed to be unchanged after 1500 charge–discharge cycles revealing a promising potential for future applications. Furthermore, the mechanical properties are assessed by means of four-point bending and tensile tests. Additionally, the influence of mechanical loads on the electrical properties is also investigated, demonstrating the storage stability of the composites.
Water Storage Instead of Energy Storage for Desalination Powered by Renewable Energy—King Island Case Study

Directory of Open Access Journals (Sweden)

Aya Tafech

2016-10-01

Full Text Available In this paper, we scrutinized the energy storage options used in mitigation of the intermittent nature of renewable energy resources for desalination process. In off-grid islands and remote areas, renewable energy is often combined with appropriate energy storage technologies (ESTs to provide a consistent and reliable electric power source. We demonstrated that in developing a renewable energy scheme for desalination purposes, product (water storage is a more reliable and techno-economic solution. For a King Island (Southeast Australia case-study, electric power production from renewable energy sources was sized under transient conditions to meet the dynamic demand of freshwater throughout the year. Among four proposed scenarios, we found the most economic option by sizing a 13 MW solar photovoltaic (PV field to instantly run a proportional RO desalination plant and generate immediate freshwater in diurnal times without the need for energy storage. The excess generated water was stored in 4 × 50 ML (mega liter storage tanks to meet the load in those solar deficit times. It was also demonstrated that integrating well-sized solar PV with wind power production shows more consistent energy/water profiles that harmonize the transient nature of energy sources with the water consumption dynamics, but that would have trivial economic penalties caused by larger desalination and water storage capacities.
Conference on storage in the service of energy transition

International Nuclear Information System (INIS)

Leuthold, Matthias; Marchal, David; Sitte, Ralf; Kairies, Kai-Philipp; Guerrier, Pierre; Netzel, Niklas; Radvanyi, Etienne; Lenck, Thorsten

2016-01-01

The French-German office for Renewable energies (OFAEnR) organised a conference on energy storage supporting the energy transition in France and in Germany. In the framework of this French-German exchange of experience, about 140 participants met together to debate about the answer of future storage technologies to the electric power system needs and to the optimum integration of renewable energies at different levels of the power transmission and distribution grid. This document brings together the available presentations (slides) made during this event: 1 - Storage Technologies, Status and Perspectives (Matthias Leuthold); 2 - Which electricity storage needs for 2030, 2050 in France? (David Marchal); 3 - Storage in context of the German 'Energiewende' (Ralf Sitte); 4 - Battery Storage for residential PV Systems: Grid relieving effects (Kai-Philipp Kairies); 5 - Battery Storage for residential PV Systems: Technologies and Market Trends (Kai-Philipp Kairies); 6 - Pumped hydro-stations to ensure a decentralized and flexible storage to integrate the best way RES in the electric system (Pierre Guerrier); 7 - RRKW Feldheim - Primary Frequency Control in a wind feed-in grid (Niklas Netzel); 8 - Smoothing an intermittent generation: interest of generation forecast and storage global management (Etienne Radvanyi); 9 - Power-to-gas after 2030 - A cost-benefit analysis (Thorsten Lenck)
Energy Efficiency Analysis of Discharge Modes of an Adiabatic Compressed Air Energy Storage System

OpenAIRE

Shane D. Inder; Mehrdad Khamooshi

2017-01-01

Efficient energy storage is a crucial factor in facilitating the uptake of renewable energy resources. Among the many options available for energy storage systems required to balance imbalanced supply and demand cycles, compressed air energy storage (CAES) is a proven technology in grid-scale applications. This paper reviews the current state of micro scale CAES technology and describes a micro-scale advanced adiabatic CAES (A-CAES) system, where heat generated during compression is stored fo...
Simulation of Mechanical Processes in Gas Storage Caverns for Short-Term Energy Storage

Science.gov (United States)

Böttcher, Norbert; Nagel, Thomas; Kolditz, Olaf

2015-04-01

In recent years, Germany's energy management has started to be transferred from fossil fuels to renewable and sustainable energy carriers. Renewable energy sources such as solar and wind power are subjected by fluctuations, thus the development and extension of energy storage capacities is a priority in German R&D programs. This work is a part of the ANGUS+ Project, funded by the federal ministry of education and research, which investigates the influence of subsurface energy storage on the underground. The utilization of subsurface salt caverns as a long-term storage reservoir for fossil fuels is a common method, since the construction of caverns in salt rock is inexpensive in comparison to solid rock formations due to solution mining. Another advantage of evaporate as host material is the self-healing behaviour of salt rock, thus the cavity can be assumed to be impermeable. In the framework of short-term energy storage (hours to days), caverns can be used as gas storage reservoirs for natural or artificial fuel gases, such as hydrogen, methane, or compressed air, where the operation pressures inside the caverns will fluctuate more frequently. This work investigates the influence of changing operation pressures at high frequencies on the stability of the host rock of gas storage caverns utilizing numerical models. Therefore, we developed a coupled Thermo-Hydro-Mechanical (THM) model based on the finite element method utilizing the open-source software platform OpenGeoSys. The salt behaviour is described by well-known constitutive material models which are capable of predicting creep, self-healing, and dilatancy processes. Our simulations include the thermodynamic behaviour of gas storage process, temperature development and distribution on the cavern boundary, the deformation of the cavern geometry, and the prediction of the dilatancy zone. Based on the numerical results, optimal operation modes can be found for individual caverns, so the risk of host rock damage
Energy Harvesting for Structural Health Monitoring Sensor Networks

Energy Technology Data Exchange (ETDEWEB)

Park, G.; Farrar, C. R.; Todd, M. D.; Hodgkiss, T.; Rosing, T.

2007-02-26

This report has been developed based on information exchanges at a 2.5-day workshop on energy harvesting for embedded structural health monitoring (SHM) sensing systems that was held June 28-30, 2005, at Los Alamos National Laboratory. The workshop was hosted by the LANL/UCSD Engineering Institute (EI). This Institute is an education- and research-focused collaboration between Los Alamos National Laboratory (LANL) and the University of California, San Diego (UCSD), Jacobs School of Engineering. A Statistical Pattern Recognition paradigm for SHM is first presented and the concept of energy harvesting for embedded sensing systems is addressed with respect to the data acquisition portion of this paradigm. Next, various existing and emerging sensing modalities used for SHM and their respective power requirements are summarized, followed by a discussion of SHM sensor network paradigms, power requirements for these networks and power optimization strategies. Various approaches to energy harvesting and energy storage are discussed and limitations associated with the current technology are addressed. This discussion also addresses current energy harvesting applications and system integration issues. The report concludes by defining some future research directions and possible technology demonstrations that are aimed at transitioning the concept of energy harvesting for embedded SHM sensing systems from laboratory research to field-deployed engineering prototypes.
Experimental and computational analysis of a large protein network that controls fat storage reveals the design principles of a signaling network.

Science.gov (United States)

Al-Anzi, Bader; Arpp, Patrick; Gerges, Sherif; Ormerod, Christopher; Olsman, Noah; Zinn, Kai

2015-05-01

An approach combining genetic, proteomic, computational, and physiological analysis was used to define a protein network that regulates fat storage in budding yeast (Saccharomyces cerevisiae). A computational analysis of this network shows that it is not scale-free, and is best approximated by the Watts-Strogatz model, which generates "small-world" networks with high clustering and short path lengths. The network is also modular, containing energy level sensing proteins that connect to four output processes: autophagy, fatty acid synthesis, mRNA processing, and MAP kinase signaling. The importance of each protein to network function is dependent on its Katz centrality score, which is related both to the protein's position within a module and to the module's relationship to the network as a whole. The network is also divisible into subnetworks that span modular boundaries and regulate different aspects of fat metabolism. We used a combination of genetics and pharmacology to simultaneously block output from multiple network nodes. The phenotypic results of this blockage define patterns of communication among distant network nodes, and these patterns are consistent with the Watts-Strogatz model.
A Unified Monitoring Framework for Energy Consumption and Network Traffic

Directory of Open Access Journals (Sweden)

Florentin Clouet

2015-08-01

Full Text Available Providing experimenters with deep insight about the effects of their experiments is a central feature of testbeds. In this paper, we describe Kwapi, a framework designed in the context of the Grid'5000 testbed, that unifies measurements for both energy consumption and network traffic. Because all measurements are taken at the infrastructure level (using sensors in power and network equipment, using this framework has no dependencies on the experiments themselves. Initially designed for OpenStack infrastructures, the Kwapi framework allows monitoring and reporting of energy consumption of distributed platforms. In this article, we present the extension of Kwapi to network monitoring, and outline how we overcame several challenges: scaling to a testbed the size of Grid'5000 while still providing high-frequency measurements; providing long-term loss-less storage of measurements; handling operational issues when deploying such a tool on a real infrastructure.
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.
Energy storage for tokamak reactor cycles

International Nuclear Information System (INIS)

Buchanan, C.H.

1979-01-01

The inherent characteristic of a tokamak reactor requiring periodic plasma quench and reignition introduces the problem of energy storage to permit continuous electrical output to the power grid. The cycle under consideration in this paper is a 1000 second burn followed by a 100 second reignition phase. The physical size of a typical toroidal plasma reaction chamber for a tokamak reactor has been described earlier. The thermal energy storage requirements described in this reference will serve as a basis for much of the ensuing discussion
LiH thermal energy storage device

Science.gov (United States)

Olszewski, M.; Morris, D.G.

1994-06-28

A thermal energy storage device for use in a pulsed power supply to store waste heat produced in a high-power burst operation utilizes lithium hydride as the phase change thermal energy storage material. The device includes an outer container encapsulating the lithium hydride and an inner container supporting a hydrogen sorbing sponge material such as activated carbon. The inner container is in communication with the interior of the outer container to receive hydrogen dissociated from the lithium hydride at elevated temperatures. 5 figures.
Synergies between energy supply networks

DEFF Research Database (Denmark)

Wu, Jianzhnog; Yan, Jinyue; Desideri, Umberto

2017-01-01

Energy system integration uses a whole-system approach to optimize the synergies between energy supply networks to facilitate and coordinate the grid integration of distributed energy resources while enabling the synergies and conflicts between the local distribution networks and the national lev...... and integration of local renewables including solar energy wind geothermal waste heat and biomass is presented.......Energy system integration uses a whole-system approach to optimize the synergies between energy supply networks to facilitate and coordinate the grid integration of distributed energy resources while enabling the synergies and conflicts between the local distribution networks and the national level...... objectives to be understood and optimally coordinated. The latest research on the network coupling technologies analysis of synergies between energy supply networks and optimal use of synergies in network operation is discussed. A diagram on the possible interactions between different energy networks...
Voltage balancing in modular energy storage of power supply for micro resistance welding

Directory of Open Access Journals (Sweden)

Kozhushko Yu. V.

2017-10-01

Full Text Available Micro resistance welding is one of the most effective ways to obtain permanent joints of metal parts. The quality of welded joints strongly depends on the characteristics of the power supply of welding equipment. The power supplies for micro resistance welding based on Energy Storage topology have a softer impact on the network than the ones based on Direct Energy topology. The use of supercapacitors for Energy Storage type power supplies makes it possible to reduce the dimensions of welding equipment and to improve its technical parameters. However, the feature of the supercapacitors is low value of the nominal voltage, which usually does not exceed 3 V. To provide higher voltage, the modules of supercapacitors connected in series are designed. In order to extend the life time of such modules, a voltage balancing system is required. A circuit for balancing the voltage of a modular supercapacitor energy storage of a power supply for micro resistance welding is proposed. The fragments of calculation of control units of a supercapacitor module cell are given. The simulation of the balancing circuit operation is carried out and time charts of the supercapacitor charge process are obtained. The operability and effectiveness of the proposed solution is confirmed. The advantage of the proposed circuit is the possibility of obtaining the high efficiency because of returning the excessive energy of the module cell back into the power supply.

Evaluating Dihydroazulene/Vinylheptafulvene Photoswitches for Solar Energy Storage Applications.

Science.gov (United States)

Wang, Zhihang; Udmark, Jonas; Börjesson, Karl; Rodrigues, Rita; Roffey, Anna; Abrahamsson, Maria; Nielsen, Mogens Brøndsted; Moth-Poulsen, Kasper

2017-08-10

Efficient solar energy storage is a key challenge in striving toward a sustainable future. For this reason, molecules capable of solar energy storage and release through valence isomerization, for so-called molecular solar thermal energy storage (MOST), have been investigated. Energy storage by photoconversion of the dihydroazulene/vinylheptafulvene (DHA/VHF) photothermal couple has been evaluated. The robust nature of this system is determined through multiple energy storage and release cycles at elevated temperatures in three different solvents. In a nonpolar solvent such as toluene, the DHA/VHF system can be cycled more than 70 times with less than 0.01 % degradation per cycle. Moreover, the [Cu(CH 3 CN) 4 ]PF 6 -catalyzed conversion of VHF into DHA was demonstrated in a flow reactor. The performance of the DHA/VHF couple was also evaluated in prototype photoconversion devices, both in the laboratory by using a flow chip under simulated sunlight and under outdoor conditions by using a parabolic mirror. Device experiments demonstrated a solar energy storage efficiency of up to 0.13 % in the chip device and up to 0.02 % in the parabolic collector. Avenues for future improvements and optimization of the system are also discussed. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Small magnetic energy storage systems using high temperature superconductors

International Nuclear Information System (INIS)

Kumar, B.

1991-01-01

This paper reports on magnetic energy storage for power systems that has been considered for commercial utility power, air and ground mobile power sources, and spacecraft applications. Even at the current technology limits of energy storage (100 KJ/Kg*), superconducting magnetic energy storage inductors do not offer a strong advantage over state-of-the-art batteries. The commercial utility application does not have a weight and volume limitation, and is under intense study in several countries for diurnal cycle energy storage and high power delivery. The advent of high temperature superconductors has reduced one of the penalties of superconducting magnetic energy storage in that refrigeration and cryocontainers become greatly simplified. Still, structural and current density issues that limit the energy density and size of superconducting inductors do not change. Cold weather starting of aircraft engines is an application where these limitations are not as significant, and where current systems lack performance. The very cold environments make it difficult to achieve high power densities in state-of-the-art batteries and hydraulically activated starters. The same cold environments make it possible to cool superconducting systems for weeks using a single charge of liquid nitrogen. At the same, the ground carts can handle the size and weight of superconducting magnetic storage (SMES) devices
Energy storage financing :

Energy Technology Data Exchange (ETDEWEB)

Baxter, Richard

2016-08-01

Project financing is emerging as the linchpin for the future health, direction, and momentum of the energy storage industry. Market leaders have so far relied on selffunding or captive lending arrangements to fund projects. New lenders are proceeding hesitantly as they lack a full understanding of the technology, business, and credit risks involved in this rapidly changing market. The U.S. Department of Energy is poised to play a critical role in expanding access to capital by reducing the barriers to entry for new lenders, and providing trusted analytical benchmarks to better judge and price the risk in systematic ways.
Is inexpensive natural gas hindering the grid energy storage industry?

International Nuclear Information System (INIS)

Hittinger, Eric; Lueken, Roger

2015-01-01

Grid energy storage is a maturing technology and forecasts of the industry's growth have been promising. However, recent years have realized little growth in actual deployments of grid-level storage and several high-profile storage companies and projects have failed. We hypothesize that falling natural gas prices have significantly reduced the potential profit from many U.S. energy storage projects since 2009 and quantify that effect. We use engineering–economic models to calculate the monthly revenue to energy storage devices providing frequency regulation and energy arbitrage in several electricity markets and compare that revenue to prevailing natural gas prices. We find that flywheel devices providing frequency regulation were profitable in months when natural gas prices were above $7/mcf, but face difficulties at current prices (around $4/mcf). For energy arbitrage alone, we find that the breakeven capital cost for large-scale storage was around $300/kWh in several key locations in 2004–2008, but is around $100/kWh in the same locations today. Though cost and performance improvements have been continually decreasing the effective cost of energy services from storage, fundamental market signals indicating the need for energy storage are at or near 10-year lows for both energy arbitrage and frequency regulation. - Highlights: • We use engineering–economic models to determine breakeven capital cost of storage. • Two applications are examined: frequency regulation and energy arbitrage. • For both services, potential revenue has decreased significantly since 2008. • We show a high correlation of revenue with natural gas price. • We demonstrate a causal relationship using the PHORUM grid modeling software.
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.
Mission and status of the US Department of Energy's battery energy storage program

Science.gov (United States)

Quinn, J. E.; Hurwitch, J. W.; Landgrebe, A. R.; Hauser, S. G.

1985-05-01

The mission of the US Department of Energy's battery research program has evolved to reflect the changing conditions of the world energy economy and the national energy policy. The battery energy storage program supports the goals of the National Energy Policy Plan (FY 1984). The goals are to provide an adequate supply of energy at reasonable costs, minimize federal control and involvement in the energy marketplace, promote a balanced and mixed energy resource system, and facilitate technology transfer from the public to the private sector. This paper describes the history of the battery energy storage program and its relevance to the national interest. Potential market applications for battery energy storage are reviewed, and each technology, its goals, and its current technical status are described. The paper concludes by describing the strategy developed to ensure effective technology transfer to the private sector and reviewing past significant accomplishments.
Optimal Sizing and Placement of Battery Energy Storage in Distribution System Based on Solar Size for Voltage Regulation

Energy Technology Data Exchange (ETDEWEB)

Nazaripouya, Hamidreza [Univ. of California, Los Angeles, CA (United States); Wang, Yubo [Univ. of California, Los Angeles, CA (United States); Chu, Peter [Univ. of California, Los Angeles, CA (United States); Pota, Hemanshu R. [Univ. of California, Los Angeles, CA (United States); Gadh, Rajit [Univ. of California, Los Angeles, CA (United States)

2016-07-26

This paper proposes a new strategy to achieve voltage regulation in distributed power systems in the presence of solar energy sources and battery storage systems. The goal is to find the minimum size of battery storage and its corresponding location in the network based on the size and place of the integrated solar generation. The proposed method formulates the problem by employing the network impedance matrix to obtain an analytical solution instead of using a recursive algorithm such as power flow. The required modifications for modeling the slack and PV buses (generator buses) are utilized to increase the accuracy of the approach. The use of reactive power control to regulate the voltage regulation is not always an optimal solution as in distribution systems R/X is large. In this paper the minimum size and the best place of battery storage is achieved by optimizing the amount of both active and reactive power exchanged by battery storage and its gridtie inverter (GTI) based on the network topology and R/X ratios in the distribution system. Simulation results for the IEEE 14-bus system verify the effectiveness of the proposed approach.
World Energy Needs and Offshore Potential of hydro energy and pump storage

International Nuclear Information System (INIS)

Lemperiere, F.

2008-09-01

In 2008, 6,5 Billion people have an overall income of 50.000 Billion US $, use 10 Billion oil equivalent of primary energy, partly through 15.000 TWh of electric power. Most is used by 1 Billion people from industrialized countries, with 10.000 KWh/ year per capita at a cost of 10 cents per KWh, i.e. 1.000 $/year, 3 % of their income close to 30.000 $ per year. In the second half of the Century, we may hope that 10 Billion people will reach this average income per capita; with a better energetic efficiency but a larger share of it through electricity. The world Electricity needs may well be multiplied by 5 along the century. It is possible at a reasonable cost to transport electricity along thousands of Km but this is used only now for 1 %. It is possible to store electricity after generation (pumped storage plants between 2 lakes) but it is used now for only 1 %; energy storage is usually before electricity generation (fuel storage or lakes). But these two possibilities of storage of electricity after generation and long distance transport are the key of the future utilization of renewable energies. The key problem of wind and solar electricity is the intermittent supply and the relevant need of storage along 1 or 2 days. Without storage, wind and solar energies may be used one third of time and should be associated with much more fossil fuel power for two thirds. As fossil fuel power will be limited, wind and solar should be very limited. 2) With storage, wind and solar energies may be used over 80 % of time, much more than fossil fuel. For 10.000 TWh/year of wind energy, a 2 days storage requires a 55 TWh/storage. For 30.000 TWh/year of sun energy, a 16 hours storage requires a 55 TWh/storage. As some storage may be common and as there may be storage is some solar plants, the total storage need may be 80 to 100 TWh. It may be between two lakes: - Possibly 10 to 20 TWh between 2 onshore lakes, as for 2 TWh now (100 GW x 20 hours) - Possibly 10 to 20 TWh from
Privacy-preserving smart meter control strategy including energy storage losses

OpenAIRE

Avula, Chinni Venkata Ramana R.; Oechtering, Tobias J.; Månsson, Daniel

2018-01-01

Privacy-preserving smart meter control strategies proposed in the literature so far make some ideal assumptions such as instantaneous control without delay, lossless energy storage systems etc. In this paper, we present a one-step-ahead predictive control strategy using Bayesian risk to measure and control privacy leakage with an energy storage system. The controller estimates energy state using a three-circuit energy storage model to account for steady-state energy losses. With numerical exp...
Storage, a stake for renewable energies integration

International Nuclear Information System (INIS)

Grabette, Olivier

2013-01-01

Development of renewable energy sources is challenging the power system operation. Balancing consumption and generation at different times, from real time up to 10 years, with an increasing part of intermittent and fatal sources should indicate a clear route to storage development Up to now on opposite situation occurs. New storage project in Europe has been stopped because of missing business model, and there is no long term economical signal showing it could change in the near future. The capability to predict with a good accuracy, and share through the European transmission system the renewable production places storage in direct competition with other sources of flexibility. However, use case of storage is not limited to energy balancing. Ancillary services, connexion cost optimization, quality of supply are among other possible services offered by storage installation. For all of those, understanding technical requirements and economical issues is an initial condition to open a favourable game area for storage. Exploring new multi-service models through demonstrators, redesigning the electricity market in Europe are key initiatives to approach a new era for storage development. It doesn't prevent innovation to improve performance and reduce cost, an essential condition to give a chance for storage solution compared to other flexibility sources. (author)
Designing and Testing Composite Energy Storage Systems for Regulating the Outputs of Linear Wave Energy Converters

Directory of Open Access Journals (Sweden)

Zanxiang Nie

2017-01-01

Full Text Available Linear wave energy converters generate intrinsically intermittent power with variable frequency and amplitude. A composite energy storage system consisting of batteries and super capacitors has been developed and controlled by buck-boost converters. The purpose of the composite energy storage system is to handle the fluctuations and intermittent characteristics of the renewable source, and hence provide a steady output power. Linear wave energy converters working in conjunction with a system composed of various energy storage devices, is considered as a microsystem, which can function in a stand-alone or a grid connected mode. Simulation results have shown that by applying a boost H-bridge and a composite energy storage system more power could be extracted from linear wave energy converters. Simulation results have shown that the super capacitors charge and discharge often to handle the frequent power fluctuations, and the batteries charge and discharge slowly for handling the intermittent power of wave energy converters. Hardware systems have been constructed to control the linear wave energy converter and the composite energy storage system. The performance of the composite energy storage system has been verified in experiments by using electronics-based wave energy emulators.
Storage capacity of multi-layered neural networks with binary weights

International Nuclear Information System (INIS)

Tarkowski, W.; Hemmen, J.L. van

1997-01-01

Using statistical physics methods we investigate two-layered perceptrons which consist of N binary input neurons, K hidden units and a single output node. Four basic types of such networks are considered: the so-called Committee, Parity, and AND Machines which makes a decision based on a majority, parity, and the logical AND rules, respectively (for these cases the weights that connect hidden units and output node are taken to be equal to one), and the General Machine where one allows all the synaptic couplings to vary. For these kinds of network we examine two types of architecture: fully connected and three-connected ones (with overlapping and non-overlapping receptive fields, respectively). All the above mentioned machines heave binary weights. Our basic interest is focused on the storage capabilities of such networks which realize p= αN random, unbiased dichotomies (α denotes the so-called storage ratio). The analysis is done using the annealed approximation and is valid for all values of K. The critical (maximal) storage capacity of the fully connected Committee Machine reads α c =K, while in the case of the three-structure one gets α c =1, independent of K. The results obtained for the Parity Machine are exactly the same as those for the Committee network. The optimal storage of the AND Machine depends on distribution of the outputs for the patterns. These associations are studied in detail. We have found also that the capacity of the General Machines remains the same as compared to systems with fixed weights between intermediate layer and the output node. Some of the findings (especially those concerning the storage capacity of the Parity Machine) are in a good agreement with known numerical results. (author)
Fascinating Magnetic Energy Storage Nanomaterials: A Brief Review.

Science.gov (United States)

Sreenivasulu, Kummari V; Srikanth, Vadali V S S

2017-07-10

In this brief review, the importance of nanotechnology in developing novel magnetic energy storage materials is discussed. The discussion covers recent patents on permanent magnetic materials and especially covers processing of permanent magnets (rare-earth and rare-earth free magnets), importance of rare-earth permanent magnets and necessity of rare-earth free permanent magnets. Magnetic energy storage materials are those magnetic materials which exhibit very high energy product (BH)max (where B is the magnetic induction in Gauss (G) whereas H is the applied magnetic field in Oersted (Oe)). (BH)max is the direct measure of the ability of a magnetic material to store energy. In this context, processing of magnetic energy storage composite materials constituted by soft and hard magnetic materials played a predominant role in achieving high (BH)max values due to the exchange coupling phenomenon between the soft and hard magnetic phases within the composite. Magnetic energy storage composites are normally composed of rare-earth magnetic materials as well as rare-earth free magnetic materials. Nanotechnology's influence on the enhancement of energy product due to the exchange coupling phenomenon is of great prominence and therefore discussed in this review. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Energy Storage Annual Progress Report for FY15

Energy Technology Data Exchange (ETDEWEB)

Pesaran, Ahmad [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ban, Chunmei [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cao, Lei [National Renewable Energy Lab. (NREL), Golden, CO (United States); Graf, Peter [National Renewable Energy Lab. (NREL), Golden, CO (United States); Keyser, Matt [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kim, Gi-Heon [National Renewable Energy Lab. (NREL), Golden, CO (United States); Santhanagopalan, Shriram [National Renewable Energy Lab. (NREL), Golden, CO (United States); Saxon, Aron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Shi, Ying [National Renewable Energy Lab. (NREL), Golden, CO (United States); Smith, Kandler [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tenent, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Yang, Chuanbo [National Renewable Energy Lab. (NREL), Golden, CO (United States); Zhang, Chao [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-12-01

The Energy Storage research and development (R&D) subprogram within the DOE Vehicle Technologies Office (VTO) provides support and guidance for projects focusing on batteries for plug-in electric vehicles (PEVs) in support of the EV Everywhere Grand Challenge. PEVs could have a significant impact on the nation's goal of reducing dependence on imported oil and gaseous pollutant emissions. The Energy Storage program targets overcoming technical barriers to enable market success, including: (1) significantly reducing battery cost; (2) increasing battery performance (power, energy, durability); (3) reducing battery weight and volume; and (4) increasing battery tolerance to abusive conditions such as short circuit, overcharge, and crush. The National Renewable Energy Laboratory (NREL) supports the VTO's Energy Storage program by evaluating the thermal performance of cells and packs, developing electrochemical-thermal models to accelerate the design cycle for developing batteries, investigating the behavior of lithium-ion batteries under abuse conditions such as crush, enhancing the durability of electrodes by coatings such as atomic layer deposition, synthesis of materials for higher energy density batteries, and conducting techno-economic analysis of batteries in various electric-drive vehicles. This report describes the progress made by NREL on the research and development projects funded by the DOE VTO Energy Storage subprogram in FY15.
Energy Storage Requirements for Achieving 50% Solar Photovoltaic Energy Penetration in California

Energy Technology Data Exchange (ETDEWEB)

Denholm, Paul; Margolis, Robert

2016-08-01

We estimate the storage required to enable PV penetration up to 50% in California (with renewable penetration over 66%), and we quantify the complex relationships among storage, PV penetration, grid flexibility, and PV costs due to increased curtailment. We find that the storage needed depends strongly on the amount of other flexibility resources deployed. With very low-cost PV (three cents per kilowatt-hour) and a highly flexible electric power system, about 19 gigawatts of energy storage could enable 50% PV penetration with a marginal net PV levelized cost of energy (LCOE) comparable to the variable costs of future combined-cycle gas generators under carbon constraints. This system requires extensive use of flexible generation, transmission, demand response, and electrifying one quarter of the vehicle fleet in California with largely optimized charging. A less flexible system, or more expensive PV would require significantly greater amounts of storage. The amount of storage needed to support very large amounts of PV might fit within a least-cost framework driven by declining storage costs and reduced storage-duration needs due to high PV penetration.
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...... 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 the CAES process diabatic. The cooling involves exergy losses and thus lowers the efficiency...... of the storage significantly. The efficiency of CAES as an electricity storage may be defined in several ways, we discuss these and find that the exergetic efficiency of compression, storage and production together determine the efficiency of CAES. In the paper we find that the efficiency of the practical CAES...
Modeling and optimization of a network of energy hubs to improve economic and emission considerations

International Nuclear Information System (INIS)

Maroufmashat, Azadeh; Elkamel, Ali; Fowler, Michael; Sattari, Sourena; Roshandel, Ramin; Hajimiragha, Amir; Walker, Sean; Entchev, Evgueniy

2015-01-01

Energy hubs that incorporate a variety of energy generation and energy transformation technologies can be used to provide the energy storage needed to enable the efficient operation of a ‘smart energy network’. When these hubs are combined as a network and allowed to exchange energy, they create efficiency advantages in both financial and environmental performance. Further, the interconnectedness of the energy network design provides an added layer of reliability. In this paper, a complex network of energy hubs is modeled and optimized under different scenarios to examine both the financial viability and potential reduction of greenhouse gas emissions. Two case studies consisting of two and three energy hubs within a network are considered. The modeling Scenarios vary according to the consideration of distributed energy systems and energy interaction between energy hubs. In the case of a network of two energy hubs, there is no significant economic or emissions benefit with only a 0.5% reduction in total cost and 3% reduction in CO_2 emission. In the case of a network of three energy hubs, there is a significant economic benefit ranging from 11% to 29%, and 11% emission reduction benefit, as well as a 13% reduction in natural gas consumption. - Highlights: • The generic form of the modified energy hub concept with network model is presented. • Two case studies are presented to demonstrate the benefits of energy hub network. • Distributed energy is shown to provide economic and environmental advantages. • Multi criteria optimization of the economic and environmental performance is done.
New kinds of energy-storing building composite PCMs for thermal energy storage

International Nuclear Information System (INIS)

Biçer, Alper; Sarı, Ahmet

2013-01-01

Graphical abstract: In this work, 10 new kinds of BCPCMs were prepared by blending of liquid xylitol pentalaurate (XPL) and xylitol pentamyristate (XPM) esters into gypsum, cement, diatomite, perlite and vermiculite. DSC results showed that the melting temperatures and energy storage capacities of the prepared BCPCMs are in range of about 40–55 °C and 31–126 J/g, respectively. TG investigations and thermal cycling test showed that the BCPCMs had good thermal endurance and thermal reliability. It can be also concluded that among the prepared 10 kinds materials, especially the BCPCMs including perlite, vermiculite, diatomite were found to better candidates for thermal energy storage applications in buildings due to the fact that they have relatively high heat storage ability. Highlights: ► New kinds BCPCMs were prepared by blending of liquid XPL and XPM esters with some building materials. ► The BCPCMs had suitable melting temperatures and energy storage capacities. ► Especially, the BCPCMs including perlite, vermiculite, diatomite were found to better candidates for thermal energy storage. - Abstract: Energy storing-composite phase change materials (PCMs) are significant means of thermal energy storage in buildings. Although several building composite PCMs (BCPCMs) have been developed in recent years, the additional investigations are still required to enrich the diversity of BCPCMs for solar heating and energy conservation applications in buildings. For this purpose, the present work is focused the preparation, characterization and determination of 10 new kinds of BCPCMs. The BCPCMs were prepared by blending of liquid xylitol pentalaurate (XPL) and xylitol pentamyristate (XPM) esters with gypsum, cement, diatomite, perlite and vermiculite as supporting matrices. The scanning electron microscopy (SEM) and Fourier Transform Infrared (FT-IR) analysis showed that the ester compounds were adsorbed uniformly into the building materials due to capillary forces
Electric Machine Topologies in Energy Storage Systems

OpenAIRE

Santiago, Juan De; Oliveira, Janaina Goncalves de

2010-01-01

Energy storage development is essential if intermittent renewable energy generation is to increase. Pumped hydro, CAES and flywheels are environmentally friendly and economical storage alternatives that required electric motor/generators. The popularization of power electronics is relatively new and therefore the technology is still under development. There is not a clear winner when comparing technologies and therefore the optimal alternative depends on the specific requirements of the appli...
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…

Flexible energy-storage devices: design consideration and recent progress.

Science.gov (United States)

Wang, Xianfu; Lu, Xihong; Liu, Bin; Chen, Di; Tong, Yexiang; Shen, Guozhen

2014-07-23

Flexible energy-storage devices are attracting increasing attention as they show unique promising advantages, such as flexibility, shape diversity, light weight, and so on; these properties enable applications in portable, flexible, and even wearable electronic devices, including soft electronic products, roll-up displays, and wearable devices. Consequently, considerable effort has been made in recent years to fulfill the requirements of future flexible energy-storage devices, and much progress has been witnessed. This review describes the most recent advances in flexible energy-storage devices, including flexible lithium-ion batteries and flexible supercapacitors. The latest successful examples in flexible lithium-ion batteries and their technological innovations and challenges are reviewed first. This is followed by a detailed overview of the recent progress in flexible supercapacitors based on carbon materials and a number of composites and flexible micro-supercapacitors. Some of the latest achievements regarding interesting integrated energy-storage systems are also reviewed. Further research direction is also proposed to surpass existing technological bottle-necks and realize idealized flexible energy-storage devices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Required storage capacity to increase the value of renewable energy

International Nuclear Information System (INIS)

Nacht, T.

2014-01-01

The effort to achieve a more eco - friendly production of energy leads to larger shares of renewables in the electricity sector, resulting in more supply - dependency and volatility. This results in a time shift between production and consumption. In order to gain an upper hand, possibilities for transferring renewable energies from the time of production to the time when the demand occurs are researched. Energy storage systems will play a big role in this process, with pumped storage plants being the most developed and most common technology nowadays. As a first part of this thesis, the renewables in Germany are studied through the use of models on the basis of hourly measured values of the primary energy carriers for the corresponding technology. For these data series many years’ worth of measurements were considered, resulting in data for the hourly production values of the renewable energy sources. The results show a strong dependency between production and the seasons of the year. Furthermore a very small secured contribution of renewable production during times of peak load is registered, leading to the conclusion that energy storages are indeed necessary. Different strategies for the dispatch of the storage technologies pumped hydro storage, compressed air storage and hydrogen storage are developed for the region of Germany, which will be dispatched outside the energy - only market. The different strategies for the storage dispatch have the reduction of the resulting load in common, by preferably transferring renewable energy from times when it is not needed to those times with high loads. This resulting load needs to be covered by thermal power plants. The required capacities of the different storage technologies are evaluated and compared. By using pumped storage plants the increase in the value of renewables, as measured by the secure contribution during peak load hours, is determined. An analysis of different compositions of renewable production allows
FY2007 NREL Energy Storage R&D Progress Report

Energy Technology Data Exchange (ETDEWEB)

Pesaran, A.

2007-11-01

The National Renewable Energy Laboratory is engaged in research and development activities to support achieving targets and objectives set by the Energy Storage Program at the Office of FreedomCAR and Vehicle Technology in the U.S. Department of Energy. These activities include: 1. supporting the Battery Technology Development Program with battery thermal characterization and modeling and with energy storage system simulations and analysis; 2. supporting the Applied Research Program by developing thermal models to address abuse of Li-Ion batteries; and 3. supporting the Focused Long-Term Research Program by investigating improved Li-Ion battery electrode materials. This report summarizes the results of NREL energy storage activities in FY07.
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.
A hybrid optimization model of biomass trigeneration system combined with pit thermal energy storage

International Nuclear Information System (INIS)

Dominković, D.F.; Ćosić, B.; Bačelić Medić, Z.; Duić, N.

2015-01-01

Highlights: • Hybrid optimization model of biomass trigeneration system with PTES is developed. • Influence of premium feed-in tariffs on trigeneration systems is assessed. • Influence of total system efficiency on biomass trigeneration system with PTES is assessed. • Influence of energy savings on project economy is assessed. - Abstract: This paper provides a solution for managing excess heat production in trigeneration and thus, increases the power plant yearly efficiency. An optimization model for combining biomass trigeneration energy system and pit thermal energy storage has been developed. Furthermore, double piping district heating and cooling network in the residential area without industry consumers was assumed, thus allowing simultaneous flow of the heating and cooling energy. As a consequence, the model is easy to adopt in different regions. Degree-hour method was used for calculation of hourly heating and cooling energy demand. The system covers all the yearly heating and cooling energy needs, while it is assumed that all the electricity can be transferred to the grid due to its renewable origin. The system was modeled in Matlab© on hourly basis and hybrid optimization model was used to maximize the net present value (NPV), which was the objective function of the optimization. Economic figures become favorable if the economy-of-scale of both power plant and pit thermal energy storage can be utilized. The results show that the pit thermal energy storage was an excellent option for storing energy and shaving peaks in energy demand. Finally, possible switch from feed-in tariffs to feed-in premiums was assessed and possible subsidy savings have been calculated. The savings are potentially large and can be used for supporting other renewable energy projects
Performance Evaluation of Lower-Energy Energy Storage Alternatives for Full-Hybrid Vehicles; NREL (National Renewable Energy Laboratory)

Energy Technology Data Exchange (ETDEWEB)

Gonder, J.; Cosgrove, J.; Pesaran, A.

2014-02-11

Automakers have been mass producing hybrid electric vehicles (HEVs) for well over a decade, and the technology has proven to be very effective at reducing per-vehicle fuel use. However, the incremental cost of HEVs such as the Toyota Prius or Ford Fusion Hybrid remains several thousand dollars higher than the cost of comparable conventional vehicles, which has limited HEV market penetration. The b b b b battery energy storage device is typically the component with the greatest contribution toward this cost increment, so significant cost reductions/performance improvements to the energy storage system (ESS) can correspondingly improve the vehicle-level cost/benefit relationship. Such an improvement would in turn lead to larger HEV market penetration and greater aggregate fuel savings. The United States Advanced Battery Consortium (USABC) and the U.S. Department of Energy (DOE) Energy Storage Program managers asked the National Renewable Energy Laboratory (NREL) to collaborate with a USABC Workgroup and analyze the trade-offs between vehicle fuel economy and reducing the decade-old minimum energy requirement for power-assist HEVs. NREL’s analysis showed that significant fuel savings could still be delivered from an ESS with much lower energy storage than the previous targets, which prompted USABC to issue a new set of lower-energy ESS (LEESS) targets that could be satisfied by a variety of technologies. With support from DOE, NREL has developed an HEV test platform for in-vehicle performance and fuel economy validation testing of the hybrid system using such LEESS devices. This presentation describes development of the vehicle test platform, and laboratory as well as in-vehicle evaluation results with alternate energy storage configurations as compared to the production battery system. The alternate energy storage technologies considered include lithium-ion capacitors -- i.e., asymmetric electrochemical energy storage devices possessing one electrode with battery
Carbon footprint reductions via grid energy storage systems

Energy Technology Data Exchange (ETDEWEB)

Hale, Trevor S. [Naval Facilities Engineering Service Center, 1100 23rd Avenue, Port Huenem, CA 93043 (United States); Department of Management, Marketing, and Business Administration, University of Houston - Downtown, Houston, Texas (United States); Weeks, Kelly [Department of Maritime Administration, Texas A and M University at Galveston, Galveston, TX 77553 (United States); Tucker, Coleman [Department of Management, Marketing, and Business Administration, University of Houston - Downtown, Houston, Texas 77002 (United States)

2011-07-01

This effort presents a framework for reducing carbon emissions through the use of large-scale grid-energy-storage (GES) systems. The specific questions under investigation herein are as follows: Is it economically sound to invest in a GES system and is the system at least carbon footprint neutral? This research will show the answer to both questions is in the affirmative. Scilicet, when utilized judiciously, grid energy storage systems can be both net present value positive as well as be total carbon footprint negative. The significant contribution herein is a necessary and sufficient condition for achieving carbon footprint reductions via grid energy storage systems.
Impacts of compressed air energy storage plant on an electricity market with a large renewable energy portfolio

International Nuclear Information System (INIS)

Foley, A.; Díaz Lobera, I.

2013-01-01

Renewable energy generation is expected to continue to increase globally due to renewable energy targets and obligations to reduce greenhouse gas emissions. Some renewable energy sources are variable power sources, for example wind, wave and solar. Energy storage technologies can manage the issues associated with variable renewable generation and align non-dispatchable renewable energy generation with load demands. Energy storage technologies can play different roles in each of the step of the electric power supply chain. Moreover, large scale energy storage systems can act as renewable energy integrators by smoothing the variability. Compressed air energy storage is one such technology. This paper examines the impacts of a compressed air energy storage facility in a pool based wholesale electricity market in a power system with a large renewable energy portfolio
Integration of dispenser-printed ultra-low-voltage thermoelectric and energy storage devices

International Nuclear Information System (INIS)

Wang, Z; Chen, A; Winslow, R; Madan, D; Nill, M; Wright, P K; Juang, R C; Evans, J W

2012-01-01

This paper reports on an integrated energy harvesting prototype that consists of dispenser-printed thermoelectric energy harvesting and electrochemical energy storage devices. Parallel-connected thermoelectric devices with low internal resistances were designed, fabricated and characterized. The use of a commercially available dc-to-dc converter was explored to step-up a 27.1 mV input voltage from a printed thermoelectric device to a regulated 2.34 V output at a maximum of 34% conversion efficiency. The regulated power succeeds in charging dispenser-printed, zinc-based micro-batteries with charging efficiencies of up to 67%. The prototype presented in this work demonstrates the feasibility of deploying a printable, cost-effective and perpetual power solution for practical wireless sensor network applications. (paper)
Thermodynamic analysis of a liquid air energy storage system

International Nuclear Information System (INIS)

Guizzi, Giuseppe Leo; Manno, Michele; Tolomei, Ludovica Maria; Vitali, Ruggero Maria

2015-01-01

The rapid increase in the share of electricity generation from renewable energy sources is having a profound impact on the power sector; one of the most relevant effects of this trend is the increased importance of energy storage systems, which can be used to smooth out peaks and troughs of production from renewable energy sources. Besides their role in balancing the electric grid, energy storage systems may provide also several other useful services, such as price arbitrage, stabilizing conventional generation, etc.; therefore, it is not surprising that many research projects are under way in order to explore the potentials of new technologies for electric energy storage. This paper presents a thermodynamic analysis of a cryogenic energy storage system, based on air liquefaction and storage in an insulated vessel. This technology is attractive thanks to its independence from geographical constraints and because it can be scaled up easily to grid-scale ratings, but it is affected by a low round-trip efficiency due to the energy intensive process of air liquefaction. The present work aims to assess the efficiency of such a system and to identify if and how it can achieve an acceptable round-trip efficiency (in the order of 50–60%).
Storing energy for cooling demand management in tropical climates: A techno-economic comparison between different energy storage technologies

International Nuclear Information System (INIS)

Comodi, Gabriele; Carducci, Francesco; Sze, Jia Yin; Balamurugan, Nagarajan; Romagnoli, Alessandro

2017-01-01

This paper addresses the role of energy storage in cooling applications. Cold energy storage technologies addressed are: Li-Ion batteries (Li-Ion EES), sensible heat thermal energy storage (SHTES); phase change material (PCM TES), compressed air energy storage (CAES) and liquid air energy storage (LAES). Batteries and CAES are electrical storage systems which run the cooling systems; SHTES and PCM TES are thermal storage systems which directly store cold energy; LAES is assessed as a hybrid storage system which provides both electricity (for cooling) and cold energy. A hybrid quantitative-qualitative comparison is presented. Quantitative comparison was investigated for different sizes of daily cooling energy demand and three different tariff scenarios. A techno-economic analysis was performed to show the suitability of the different storage systems at different scales. Three parameters were used (Pay-back period, Savings-per-energy-unit and levelized-cost-of-energy) to analyze and compare the different scenarios. The qualitative analysis was based on five comparison criteria (Complexity, Technology Readiness Level, Sustainability, Flexibility and Safety). Results showed the importance of weighing the pros and cons of each technology to select a suitable cold energy storage system. Techno-economic analysis highlighted the fundamental role of tariff scenario: a greater difference between peak and off-peak electricity tariff leads to a shorter payback period of each technology. - Highlights: • Techno-economic evaluation of energy storage solutions for cooling applications. • Comparison between five energy storage (EES, SHTES, PCM, CAES, LAES) is performed. • Qualitative and quantitative performance parameters were used for the analysis. • LAES/PCM can be valid alternatives to more established technologies EES, SHTES, CAES. • Tariffs, price arbitrage and investment cost play a key role in energy storage spread.
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.
Energy storage label : a method for comparing storage systems over all ranges

NARCIS (Netherlands)

Pierie, Frank; van Someren, Christian

2015-01-01

This report describes the creation and use of a database for energy storage technologies which was developed in conjunction with Netbeheer Nederland and the Hanze University of Applied Sciences. This database can be used to make comparisons between a selection of storage technologies and will
Battery storage for supplementing renewable energy systems

Energy Technology Data Exchange (ETDEWEB)

None, None

2009-01-18

The battery storage for renewable energy systems section of the Renewable Energy Technology Characterizations describes structures and models to support the technical and economic status of emerging renewable energy options for electricity supply.
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)
A Network-Attached Storage System Supporting Guaranteed QoS

Institute of Scientific and Technical Information of China (English)

KONG Hua-feng; YU Sheng-sheng; LU Hong-wei

2005-01-01

We propose a network-attached storage system that can support guaranteed Quality of Service (QoS), called POPNet Storage. The special policy of date access and disk scheduling is enable users to access files quickly and directly with guaranteed QoS in the POPNet Storage. The POPNet Storage implements a measurement-based admission control algorithm (PSMBAC) to determine whether to admit a new data access request stream and admit as many requests as possible while meeting the QoS guarantees to its clients. The data reconstruction algorithms in the POPNet Storage also put more emphasis on data availability and guaranteed QoS, thus it is designed to complete the data recovery as soon as possible and at the same time provide the guaranteed QoS for high-priority data access. The experiment results show that the POPNet Storage can provide more significant performance, reliability, and guaranteed QoS than conventional storage systems.
Energy storage system in medium-sized voltage lines for the integration of decentralized fluctuating energy sources; Energiespeicher im Niederspannungsnetz zur Integration dezentraler, fluktuierender Energiequellen

Energy Technology Data Exchange (ETDEWEB)

Bodach, M.

2006-06-30

The solar radiation fluctuates due to atmospheric and planetary influences. Concerning PV systems, the changes from dark clouds to clear sky result in fast and very deep fluctuations of the time behaviour of the power output fed into the low voltage (LV) network by DC-AC-Converters. On the example of a daily recorded global radiation curve with a very short sampling time (regular interval time 1 s) the paper shows that short-term sags of the solar radiation are possible up to 80% of the previous value as a result of sudden and intensive changes of the density of the clouds. These disturbances of the quality of the generated electric power are directly transformed into the LV grids. If the number of PV systems connected to existing LV networks rises essentially, the fluctuating photovoltaic energy generation will achieve a very high importance and therefore not only the well-known, but also a lot of new problems will occur. They have already been investigated theoretically in different papers and they have also been proven quantitatively by own simulations. Improvements of the energy quality at the point of common coupling will be possible if the grid-coupled PV power plants are supplemented with suitable intelligent storage systems bridging the short-term sags. So the influence of the fluctuating radiation on the generated power can be fundamentally reduced. The developed intelligent short-term storage system smoothes out the generated power of the PV system by means of a storage. It is based on the very high capacity of an electric double layer (UltraCap, produced by EPCOS) and includes a complex electronic control system. The UltraCap has the required storing characteristics and has been adjusted to the system voltage by a highly sophisticated microprocessor controlled DC/DC-converter system. Such an intelligent storage system can also be used for the connection of other decentralised power generation units (e.g. fuel cells, block-unit heating power plant) to the
Mixed Solutions of Electrical Energy Storage

Directory of Open Access Journals (Sweden)

Chioncel Cristian Paul

2012-01-01

Full Text Available The paper presents electrical energy storage solutions using electricbatteries and supercapacitors powered from photovoltaic solarmodules, with possibilities of application in electric and hybrid vehicles.The future development of electric cars depends largely on electricalenergy storage solutions that should provide a higher range of roadand operating parameters comparable to those equipped with internalcombustion engines, that eliminate pollution.
Energy Storage and Retrieval

Indian Academy of Sciences (India)

Annual Meetings · Mid Year Meetings · Discussion Meetings · Public Lectures · Lecture Workshops · Refresher Courses · Symposia · Live Streaming. Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 6. Energy Storage and Retrieval The Secondary Battery Route. A K Shukla P Vishnu Kamath.
An adaptive cryptographic accelerator for network storage security on dynamically reconfigurable platform

Science.gov (United States)

Tang, Li; Liu, Jing-Ning; Feng, Dan; Tong, Wei

2008-12-01

Existing security solutions in network storage environment perform poorly because cryptographic operations (encryption and decryption) implemented in software can dramatically reduce system performance. In this paper we propose a cryptographic hardware accelerator on dynamically reconfigurable platform for the security of high performance network storage system. We employ a dynamic reconfigurable platform based on a FPGA to implement a PowerPCbased embedded system, which executes cryptographic algorithms. To reduce the reconfiguration latency, we apply prefetch scheduling. Moreover, the processing elements could be dynamically configured to support different cryptographic algorithms according to the request received by the accelerator. In the experiment, we have implemented AES (Rijndael) and 3DES cryptographic algorithms in the reconfigurable accelerator. Our proposed reconfigurable cryptographic accelerator could dramatically increase the performance comparing with the traditional software-based network storage systems.

The Solar Energy Trifecta: Solar + Storage + Net Metering | State, Local,

Science.gov (United States)

and Tribal Governments | NREL The Solar Energy Trifecta: Solar + Storage + Net Metering The Solar Energy Trifecta: Solar + Storage + Net Metering February 12, 2018 by Benjamin Mow Massachusetts (DPU) seeking an advisory ruling on the eligibility of pairing solar-plus-storage systems with current
Experimental and computational analysis of a large protein network that controls fat storage reveals the design principles of a signaling network.

Directory of Open Access Journals (Sweden)

Bader Al-Anzi

2015-05-01

Full Text Available An approach combining genetic, proteomic, computational, and physiological analysis was used to define a protein network that regulates fat storage in budding yeast (Saccharomyces cerevisiae. A computational analysis of this network shows that it is not scale-free, and is best approximated by the Watts-Strogatz model, which generates "small-world" networks with high clustering and short path lengths. The network is also modular, containing energy level sensing proteins that connect to four output processes: autophagy, fatty acid synthesis, mRNA processing, and MAP kinase signaling. The importance of each protein to network function is dependent on its Katz centrality score, which is related both to the protein's position within a module and to the module's relationship to the network as a whole. The network is also divisible into subnetworks that span modular boundaries and regulate different aspects of fat metabolism. We used a combination of genetics and pharmacology to simultaneously block output from multiple network nodes. The phenotypic results of this blockage define patterns of communication among distant network nodes, and these patterns are consistent with the Watts-Strogatz model.
FY2014 Energy Storage R&D Annual Progress Report

Energy Technology Data Exchange (ETDEWEB)

none,

2015-03-01

The Energy Storage research and development (R&D) subprogram within the DOE Vehicle Technologies Office (VTO) provides support and guidance for projects focusing on batteries for plug-in electric vehicles. Program targets focus on overcoming technical barriers to enable market success including: (1) significantly reducing battery cost, (2) increasing battery performance (power, energy, durability), (3) reducing battery weight & volume, and (4) increasing battery tolerance to abusive conditions such as short circuit, overcharge, and crush. This report describes the progress made on the research and development projects funded by the Energy Storage subprogram in 2014. You can download individual sections at the following website, http://energy.gov/eere/vehicles/downloads/vehicle-technologies-office-2014-energy-storage-rd-annual-report.
Feasibility study and economic analysis of pumped hydro storage and battery storage for a renewable energy powered island

International Nuclear Information System (INIS)

Ma, Tao; Yang, Hongxing; Lu, Lin

2014-01-01

Highlights: • Batteries and pumped hydro storage schemes are examined. • Sizing procedure for each option is investigated in detail. • The two schemes are compared in terms of life cycle cost and technical viability. • Sensitivity analyses are conducted on five key input parameters. - Abstract: This study examined and compared two energy storage technologies, i.e. batteries and pumped hydro storage (PHS), for the renewable energy powered microgrid power supply system on a remote island in Hong Kong. The problems of energy storage for off-grid renewable energy were analyzed. The sizing methods and economic models were developed, and finally applied in the real project (case study). The results provide the most suitable energy storage scheme for local decision-makers. The two storage schemes were further divided into 4 options. Accordingly, the life-cycle costs (LCC), levelized costs for the renewable energy storage system (LCRES) and the LCC ratios between all options were calculated and compared. It was found that the employment of conventional battery (Option 2) had a higher LCC value than the advanced deep cycle battery (Option 1), indicating that using deep cycle batteries is more suitable for a standalone renewable power supply system. The pumped storage combined with battery bank option (Option 3) had only 55% LCC of that of Option 1, making this combined option more cost-competitive than the sole battery option. The economic benefit of pumped storage is even more significant in the case of purely pumped storage with a hydraulic controller (Option 4), with the lowest LCC among all options at 29–48% of Option 1. Sensitivity analysis demonstrates that PHS is even more cost competitive by controlling some adjustments such as increasing energy storage capacity and days of autonomy. Therefore, the renewable energy system coupled with pumped storage presents technically feasible opportunities and practical potential for continuous power supply in remote
From Molecular Electronics to Solar Thermal Energy Storage

DEFF Research Database (Denmark)

Olsen, Stine Tetzschner

The Sun's signicant resource potential provides a solution for the world's increasing energy demand in a sustainable and responsible manner. However, the intrinsic property of the on-o cycles of the solar irradiation, i.e. daynight, sunny-cloudy, and summer-winter, constitutes a signicant challenge...... for the utilization of solar energy. An eective technology for storing the solar energy is required. This thesis focuses on solar thermal energy storage in molecules, since it oers a very compact and eective storage method. The rst chapter after the introduction of the thesis, chapter two, introduces the fundamental...... properties of the molecule, i.e. the electronic behaviour of the molecule in dierent environments, which is a key property for investigations of solar energy storage. The main focus of the research is on the electron transport in the Coulomb blockade regime. The third chapter goes into the challenge...
Exergy and Energy Analysis of Low Temperature District Heating Network

DEFF Research Database (Denmark)

Li, Hongwei; Svendsen, Svend

is in line with a pilot project that is carrying out in Denmark with network supply/return temperature at 55oC/25 oC. The consumer domestic hot water (DHW) demand is supplied with a special designed district heating (DH) storage tank. The space heating (SH) demand is supplied with a low temperature radiator......Low temperature district heating (LTDH) with reduced network supply and return temperature provides better match of the low quality building thermal demand and the low quality waste heat supply. In this paper, an exemplary LTDH network was designed for 30 low energy demand residential houses, which....... The network thermal and hydraulic conditions were simulated under steady state with an in-house district heating network design and simulation code. Through simulation, the overall system energetic and exergetic efficiencies were calculated and the exergy losses for the major district heating system...
Critical phenomena and their effect on thermal energy storage in supercritical fluids

International Nuclear Information System (INIS)

Hobold, Gustavo M.; Da Silva, Alexandre K.

2017-01-01

Highlights: •High power thermal energy storage using supercritical fluids. •Influence of property variation on energy and power density. •Multi-fluid analysis and generalization for several storage temperatures. •Cost, heat transfer and energy density evaluation for high temperature storage. -- Abstract: Large-scale implementation of concentrated solar power plants requires energy storage systems if fossil sources are to be fully replaced. While several candidates have appeared, most still face major issues such as cost, limited energy density and material compatibility. The present paper explores the influence of property variation in the proximity of the critical point on thermal energy storage using supercritical fluids (sTES) from thermodynamic and heat transfer standpoints. Influence of thermodynamic operational parameters on energy density of isobaric and isochoric sTES and their optima is discussed, showing that the energy density results from a competition between average specific heat and loaded density. Moreover, sTES is shown to be applicable to virtually any storage temperature, depending only on the fluid’s critical point. Finally, a heat transfer and energy density comparison to other existing storage mechanisms is presented and supercritical water is shown to be competitive for high temperature thermal energy storage.
Use of some industrial waste as energy storage media

International Nuclear Information System (INIS)

Tayeb, A.M.

1996-01-01

Solar energy is stored using different solid storage materials, both chemical and metallic industrial wastes. The materials tested in the present study are paraffin wax, copper slag, aluminium slag, iron slag, cast iron slag and copper chips. Solar energy is stored in these materials and energy ia then recovered with water stream at different flow rates and the storage capacity and period for different materials were compared. The same set of experiments is run on solid metallic materials mixed with wax. The results indicated that iron slag has the highest storage capacity followed by cast iron slag then aluminium slag and copper chips and copper slag. It is also noted that addition of paraffin wax to the solid metallic material improves its storage capacity and duration greatly. The storage efficiency of different units is calculated and compared. 5 figs
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

In October 2013, the California Public Utilities Commission (CPUC) finalized procurement targets and other requirements to its jurisdictional utilities for a minimum of 1,325 MW of 'viable and cost-effective' energy storage systems by 2020. The goal of this study is to explore several aspects of grid operations in California and the Western Interconnection resulting from meeting the CPUC storage targets. We perform this analysis using a set of databases and grid simulation tools developed and implemented by the CPUC, the California Independent System Operator (CAISO), and the California Energy Commission (CEC) for the CPUC's Long-term Procurement Plan (LTPP). The 2014 version of this database contains information about generators, storage, transmission, and electrical demand, for California in the year 2024 for both 33% and 40% renewable energy portfolios. We examine the value of various services provided by energy storage in these scenarios. Sensitivities were performed relating to the services energy storage can provide, the capacity and duration of storage devices, export limitations, and negative price floor variations. Results show that a storage portfolio, as outlined by the CPUC, can reduce curtailment and system-wide production costs for 33% and 40% renewable scenarios. A storage device that can participate in energy and ancillary service markets provides the grid with the greatest benefit; the mandated storage requirement of 1,325 MW was estimated to reduce the total cost of production by about 78 million per year in the 33% scenario and 144 million per year in the 40% scenario. Much of this value is derived from the avoided start and stop costs of thermal generators and provision of ancillary services. A device on the 2024 California grid and participating in only ancillary service markets can provide the system with over 90% of the value as the energy and ancillary service device. The analysis points to the challenge of new storage
Energy storage, compression, and switching. Vol. 2

International Nuclear Information System (INIS)

Nardi, V.; Bostick, W.H.; Sahlin, H.

1983-01-01

This book is a compilation of papers presented at the Second International Conference on Energy Storage, Compression, and Switching, which was held in order to assemble active researchers with a major interest in plasma physics, electron beams, electric and magnetic energy storage systems, high voltage and high current switches, free-electron lasers, and pellet implosion plasma focus. Topics covered include: Slow systems: 50-60 Hz machinery, homopolar generators, slow capacitors, inductors, and solid state switches; Intermediate systems: fast capacitor banks; superconducting storage and switching; gas, vacuum, and dielectric switching; nonlinear (magnetic) switching; imploding liners capacitors; explosive generators; and fuses; and Fast systems: Marx, Blumlein, oil, water, and pressurized water dielectrics; switches; magnetic insulation; electron beams; and plasmas
Graphitic design: prospects of graphene-based nanocomposites for solar energy conversion, storage, and sensing.

Science.gov (United States)

Lightcap, Ian V; Kamat, Prashant V

2013-10-15

Graphene not only possesses interesting electrochemical behavior but also has a remarkable surface area and mechanical strength and is naturally abundant, all advantageous properties for the design of tailored composite materials. Graphene-semiconductor or -metal nanoparticle composites have the potential to function as efficient, multifunctional materials for energy conversion and storage. These next-generation composite systems could possess the capability to integrate conversion and storage of solar energy, detection, and selective destruction of trace environmental contaminants or achieve single-substrate, multistep heterogeneous catalysis. These advanced materials may soon become a reality, based on encouraging results in the key areas of energy conversion and sensing using graphene oxide as a support structure. Through recent advances, chemists can now integrate such processes on a single substrate while using synthetic designs that combine simplicity with a high degree of structural and composition selectivity. This progress represents the beginning of a transformative movement leveraging the advancements of single-purpose chemistry toward the creation of composites designed to address whole-process applications. The promising field of graphene nanocomposites for sensing and energy applications is based on fundamental studies that explain the electronic interactions between semiconductor or metal nanoparticles and graphene. In particular, reduced graphene oxide is a suitable composite substrate because of its two-dimensional structure, outstanding surface area, and electrical conductivity. In this Account, we describe common assembly methods for graphene composite materials and examine key studies that characterize its excited state interactions. We also discuss strategies to develop graphene composites and control electron capture and transport through the 2D carbon network. In addition, we provide a brief overview of advances in sensing, energy conversion
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. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
A full-sunlight-driven photocatalyst with super long-persistent energy storage ability.

Science.gov (United States)

Li, Jie; Liu, Yuan; Zhu, Zhijian; Zhang, Guozhu; Zou, Tao; Zou, Zhijun; Zhang, Shunping; Zeng, Dawen; Xie, Changsheng

2013-01-01

A major drawback of traditional photocatalysts like TiO2 is that they can only work under illumination, and the light has to be UV. As a solution for this limitation, visible-light-driven energy storage photocatalysts have been developed in recent years. However, energy storage photocatalysts that are full-sunlight-driven (UV-visible-NIR) and possess long-lasting energy storage ability are lacking. Here we report, a Pt-loaded and hydrogen-treated WO3 that exhibits a strong absorption at full-sunlight spectrum (300-1,000 nm), and with a super-long energy storage time of more than 300 h to have formaldehyde degraded in dark. In this new material system, the hydrogen treated WO3 functions as the light harvesting material and energy storage material simultaneously, while Pt mainly acts as the cocatalyst to have the energy storage effect displayed. The extraordinary full-spectrum absorption effect and long persistent energy storage ability make the material a potential solar-energy storage and an effective photocatalyst in practice.
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.
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).
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.
Functionalization of graphene for efficient energy conversion and storage.

Science.gov (United States)

Dai, Liming

2013-01-15

As global energy consumption accelerates at an alarming rate, the development of clean and renewable energy conversion and storage systems has become more important than ever. Although the efficiency of energy conversion and storage devices depends on a variety of factors, their overall performance strongly relies on the structure and properties of the component materials. Nanotechnology has opened up new frontiers in materials science and engineering to meet this challenge by creating new materials, particularly carbon nanomaterials, for efficient energy conversion and storage. As a building block for carbon materials of all other dimensionalities (such as 0D buckyball, 1D nanotube, 3D graphite), the two-dimensional (2D) single atomic carbon sheet of graphene has emerged as an attractive candidate for energy applications due to its unique structure and properties. Like other materials, however, a graphene-based material that possesses desirable bulk properties rarely features the surface characteristics required for certain specific applications. Therefore, surface functionalization is essential, and researchers have devised various covalent and noncovalent chemistries for making graphene materials with the bulk and surface properties needed for efficient energy conversion and storage. In this Account, I summarize some of our new ideas and strategies for the controlled functionalization of graphene for the development of efficient energy conversion and storage devices, such as solar cells, fuel cells, supercapacitors, and batteries. The dangling bonds at the edge of graphene can be used for the covalent attachment of various chemical moieties while the graphene basal plane can be modified via either covalent or noncovalent functionalization. The asymmetric functionalization of the two opposite surfaces of individual graphene sheets with different moieties can lead to the self-assembly of graphene sheets into hierarchically structured materials. Judicious
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......This paper studies operation decisions of energy storage facilities in perfectly and imperfectly competitive markets. In a perfectly competitive market, the storage facility is operated to maximize the social welfare. However, in a imperfectly competitive market, the storage facility operates...
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.
Exchanging and Storing Energy. Reducing Energy Demand through Heat Exchange between Functions and Temporary Storage

Energy Technology Data Exchange (ETDEWEB)

Sillem, E.

2011-06-15

As typical office buildings from the nineties have large heating and cooling installations to provide heat or cold wherever and whenever needed, more recent office buildings have almost no demand for heating due to high internal heat loads caused by people, lighting and office appliances and because of the great thermal qualities of the contemporary building envelope. However, these buildings still have vast cooling units to cool down servers and other energy consuming installations. At the same time other functions such as dwellings, swimming pools, sporting facilities, archives and museums still need to be heated most of the year. In the current building market there is an increasing demand for mixed-use buildings or so called hybrid buildings. The Science Business Centre is no different and houses a conference centre, offices, a museum, archives, an exhibition space and a restaurant. From the initial program brief it seemed that the building will simultaneously house functions that need cooling most of the year and functions that will need to be heated the majority of the year. Can this building be equipped with a 'micro heating and cooling network' and where necessary temporarily store energy? With this idea a research proposal was formulated. How can the demand for heating and cooling of the Science Business Centre be reduced by using energy exchange between different kinds of functions and by temporarily storing energy? In conclusion the research led to: four optimized installation concepts; short term energy storage in pavilion concept and museum; energy exchange between the restaurant and archives; energy exchange between the server space and the offices; the majority of heat and cold will be extracted from the soil (long term energy storage); the access heat will be generated by the energy roof; PV cells from the energy roof power all climate installations; a total energy plan for the Science Business Centre; a systematic approach for exchanging

Nanostructured Mo-based electrode materials for electrochemical energy storage.

Science.gov (United States)

Hu, Xianluo; Zhang, Wei; Liu, Xiaoxiao; Mei, Yueni; Huang, Yunhui

2015-04-21

The development of advanced energy storage devices is at the forefront of research geared towards a sustainable future. Nanostructured materials are advantageous in offering huge surface to volume ratios, favorable transport features, and attractive physicochemical properties. They have been extensively explored in various fields of energy storage and conversion. This review is focused largely on the recent progress in nanostructured Mo-based electrode materials including molybdenum oxides (MoO(x), 2 ≤ x ≤ 3), dichalconides (MoX2, X = S, Se), and oxysalts for rechargeable lithium/sodium-ion batteries, Mg batteries, and supercapacitors. Mo-based compounds including MoO2, MoO3, MoO(3-y) (0 energy storage systems because of their unique physicochemical properties, such as conductivity, mechanical and thermal stability, and cyclability. In this review, we aim to provide a systematic summary of the synthesis, modification, and electrochemical performance of nanostructured Mo-based compounds, as well as their energy storage applications in lithium/sodium-ion batteries, Mg batteries, and pseudocapacitors. The relationship between nanoarchitectures and electrochemical performances as well as the related charge-storage mechanism is discussed. Moreover, remarks on the challenges and perspectives of Mo-containing compounds for further development in electrochemical energy storage applications are proposed. This review sheds light on the sustainable development of advanced rechargeable batteries and supercapacitors with nanostructured Mo-based electrode materials.
Energy Storage: Batteries and Fuel Cells for Exploration

Science.gov (United States)

Manzo, Michelle A.; Miller, Thomas B.; Hoberecht, Mark A.; Baumann, Eric D.

2007-01-01

NASA's Vision for Exploration requires safe, human-rated, energy storage technologies with high energy density, high specific energy and the ability to perform in a variety of unique environments. The Exploration Technology Development Program is currently supporting the development of battery and fuel cell systems that address these critical technology areas. Specific technology efforts that advance these systems and optimize their operation in various space environments are addressed in this overview of the Energy Storage Technology Development Project. These technologies will support a new generation of more affordable, more reliable, and more effective space systems.
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.
Determination of Optimum Performance Strategy of Energy Storage in Power System

Directory of Open Access Journals (Sweden)

Mohammad Hosein Ranjbari

2016-06-01

Full Text Available Determination of optimal capacity for today energy storages has been specially noticed. The delay in increasing storage production capacity is one of the applications for energy storage supplies in which utilization from energy storage supplies along with improvement in the power status at peak hours of consumption may postpone the demand for installation of a new power plant module. In this essay, the optimal capacity of energy storage is determined in order to reduce exploitation costs by second-order non linear programming. This method expresses this problem with a target quadratic function based on the produced power of units and capacity of energy storage supply. The requirements have been modeled as linear equality and inequality equations. The related constraints for produced power and incremental and decremental power ratio in generators have been considered as well.
Load Frequency Control of Two-Area Network using Renewable Energy Resources and Battery Energy Storage System

Directory of Open Access Journals (Sweden)

Norhafiz Bin SALIM

2017-06-01

Full Text Available In an interconnected system, the frequency and tie-line power interchange are very susceptible with the diversification of power load demand. Literally, in a multi-area power system, the load frequency control (LFC is substantially aimed to minimise the deviations of these parameters relatively. Knowingly, the power production from renewable energy resources could offer promising solutions despite their intermittency (i.e. photovoltaic/wind generation, hence in this context, a battery energy storage system (BESS is proposed to delineate dynamic response along with grid—connection. This study has proposed LFC with BESS control method to suppress frequency deviations for a power system and being compared with photovoltaic (PV approach. The effectiveness was verified using newly developed AGC30 model of Japanese Power System and was modelled using MATLAB Simulink. Furthermore, an analysis of the tie-line power oscillations also are carried out and comparison analysis demonstrates further the reliability of the proposed model and control methods.
Energy Storage Characteristic Analysis of Voltage Sags Compensation for UPQC Based on MMC for Medium Voltage Distribution System

Directory of Open Access Journals (Sweden)

Yongchun Yang

2018-04-01

Full Text Available The modular multilevel converter (MMC, as a new type of voltage source converter, is increasingly used because it is a distributed storage system. There are many advantages of using the topological structure of the MMC on a unified power quality controller (UPQC, and voltage sag mitigation is an important use of the MMC energy storage system for the power quality compensation process. In this paper, based on the analysis of the topology of the MMC, the essence of energy conversion in a UPQC of voltage sag compensation is analyzed; then, the energy storage characteristics are calculated and analyzed to determine the performance index of voltage sag compensation; in addition, the simulation method is used to verify the voltage sag compensation characteristics of the UPQC; finally, an industrial prototype of the UPQC based on an MMC for 10 kV of medium voltage distribution network has been developed, and the basic functions of UPQC have been tested.
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...
GraphStore: A Distributed Graph Storage System for Big Data Networks

Science.gov (United States)

Martha, VenkataSwamy

2013-01-01

Networks, such as social networks, are a universal solution for modeling complex problems in real time, especially in the Big Data community. While previous studies have attempted to enhance network processing algorithms, none have paved a path for the development of a persistent storage system. The proposed solution, GraphStore, provides an…
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.
A review on technology maturity of small scale energy storage technologies★

Directory of Open Access Journals (Sweden)

Nguyen Thu-Trang

2017-01-01

Full Text Available This paper reviews the current status of energy storage technologies which have the higher potential to be applied in small scale energy systems. Small scale energy systems can be categorized as ones that are able to supply energy in various forms for a building, or a small area, or a limited community, or an enterprise; typically, they are end-user systems. Energy storage technologies are classified based on their form of energy stored. A two-step evaluation is proposed for selecting suitable storage technologies for small scale energy systems, including identifying possible technical options, and addressing techno-economic aspects. Firstly, a review on energy storage technologies at small scale level is carried out. Secondly, an assessment of technology readiness level (TRL is conducted. The TRLs are ranked according to information gathered from literature review. Levels of market maturity of the technologies are addressed by taking into account their market development stages through reviewing published materials. The TRLs and the levels of market maturity are then combined into a technology maturity curve. Additionally, market driving factors are identified by using different stages in product life cycle. The results indicate that lead-acid, micro pumped hydro storage, NaS battery, NiCd battery, flywheel, NaNiCl battery, Li-ion battery, and sensible thermal storage are the most mature technologies for small scale energy systems. In the near future, hydrogen fuel cells, thermal storages using phase change materials and thermochemical materials are expected to become more popular in the energy storage market.
One-dimensional nanomaterials for energy storage

Science.gov (United States)

Chen, Cheng; Fan, Yuqi; Gu, Jianhang; Wu, Liming; Passerini, Stefano; Mai, Liqiang

2018-03-01

The search for higher energy density, safer, and longer cycling-life energy storage systems is progressing quickly. One-dimensional (1D) nanomaterials have a large length-to-diameter ratio, resulting in their unique electrical, mechanical, magnetic and chemical properties, and have wide applications as electrode materials in different systems. This article reviews the latest hot topics in applying 1D nanomaterials, covering both their synthesis and their applications. 1D nanomaterials can be grouped into the categories: carbon, silicon, metal oxides, and conducting polymers, and we structure our discussion accordingly. Then, we survey the unique properties and application of 1D nanomaterials in batteries and supercapacitors, and provide comments on the progress and advantages of those systems, paving the way for a better understanding of employing 1D nanomaterials for energy storage.
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.
Low temperature desalination using solar collectors augmented by thermal energy storage

International Nuclear Information System (INIS)

Gude, Veera Gnaneswar; Nirmalakhandan, Nagamany; Deng, Shuguang; Maganti, Anand

2012-01-01

Highlights: ► A new low temperature desalination process using solar collectors was investigated. ► A thermal energy storage tank (TES) was included for continuous process operation. ► Solar collector area and TES volumes were optimized by theoretical simulations. ► Economic analysis for the entire process was compared with and without TES tank. ► Energy and emission payback periods for the solar collector system were reported. -- Abstract: A low temperature desalination process capable of producing 100 L/d freshwater was designed to utilize solar energy harvested from flat plate solar collectors. Since solar insolation is intermittent, a thermal energy storage system was incorporated to run the desalination process round the clock. The requirements for solar collector area as well as thermal energy storage volume were estimated based on the variations in solar insolation. Results from this theoretical study confirm that thermal energy storage is a useful component of the system for conserving thermal energy to meet the energy demand when direct solar energy resource is not available. Thermodynamic advantages of the low temperature desalination using thermal energy storage, as well as energy and environmental emissions payback period of the system powered by flat plate solar collectors are presented. It has been determined that a solar collector area of 18 m 2 with a thermal energy storage volume of 3 m 3 is adequate to produce 100 L/d of freshwater round the clock considering fluctuations in the weather conditions. An economic analysis on the desalination system with thermal energy storage is also presented.
Operational Benefits of Meeting California's Energy Storage Targets

Energy Technology Data Exchange (ETDEWEB)

Eichman, Josh; Denholm, Paul; Jorgenson, Jennie; Helman, Udi

2016-05-01

In October 2013, the California Public Utilities Commission (CPUC) finalized procurement targets and other requirements to its jurisdictional utilities for a minimum of 1,325 MW of 'viable and cost-effective' energy storage systems by 2020. The goal of this study is to explore several aspects of grid operations in California and the Western Interconnection resulting from meeting the CPUC storage targets. We perform this analysis using a set of databases and grid simulation tools developed and implemented by the CPUC, the California Independent System Operator (CAISO), and the California Energy Commission (CEC) for the CPUC's Long-term Procurement Plan (LTPP). The 2014 version of this database contains information about generators, storage, transmission, and electrical demand, for California in the year 2024 for both 33 percent and 40 percent renewable energy portfolios. We examine the value of various services provided by energy storage in these scenarios. Sensitivities were performed relating to the services energy storage can provide, the capacity and duration of storage devices, export limitations, and negative price floor variations. Results show that a storage portfolio, as outlined by the CPUC, can reduce curtailment and system-wide production costs for 33 percent and 40 percent renewable scenarios.
Screening of metal hydride pairs for closed thermal energy storage systems

International Nuclear Information System (INIS)

Aswin, N.; Dutta, Pradip; Murthy, S. Srinivasa

2016-01-01

Thermal energy storage systems based on metal/hydrides usually are closed systems composed of two beds of metal/alloy – one meant for energy storage and the other for hydrogen storage. It can be shown that a feasible operating cycle for such a system using a pair of metals/alloys operating between specified temperature values can be ensured if the equilibrium hydrogen intake characteristics satisfy certain criteria. In addition, application of first law of thermodynamics to an idealized operating cycle can provide the upper bounds of selected performance indices, namely volumetric energy storage density, energy storage efficiency and peak discharge temperature. This is demonstrated for a representative system composed of LaNi 4.7 Al 0.3 –LaNi 5 operating between 353 K and 303 K which gave values of about 56 kW h m −3 for volumetric storage density, about 85% for energy storage efficiency and 343 K for peak discharge temperature. A system level heat and mass transfer study considering the reaction kinetics, hydrogen flow between the beds and heat exchanger models is presented which gave second level estimates of about 40 kW h m −3 for volumetric energy storage density, 73% for energy storage efficiency and 334 K for peak temperature for the representative system. The results from such studies lead to identifying metal/alloy pairs which can be shortlisted for detailed studies.
A Novel Pumped Hydro Combined with Compressed Air Energy Storage System

Directory of Open Access Journals (Sweden)

Erren Yao

2013-03-01

Full Text Available A novel pumped hydro combined with compressed air energy storage (PHCA system is proposed in this paper to resolve the problems of bulk energy storage in the wind power generation industry over an area in China, which is characterised by drought and water shortages. Thermodynamic analysis of the energy storage system, which focuses on the pre-set pressure, storage volume capacity, water air volume ratio, pump performance, and water turbine performance of the storage system, is also presented. This paper discovers how such parameters affect the performance of the whole system. The ideal performance of this novel system has the following advantages: a simple, highly effective and low cost structure, which is comparable to the efficiency of a traditional pumped hydro storage system. Research results show a great solution to the current storage constraints encountered in the development of the wind power industry in China, which have been widely recognised as a bottleneck in the wind energy storage industry.
Deployment of Wireless Sensor Networks in Crop Storages

DEFF Research Database (Denmark)

Juul, Jakob Pilegaard; Green, Ole; Jacobsen, Rune Hylsberg

2015-01-01

of a wireless sensor network based system that provides continuous, automatic, and up-to-date information on a crop storage, while presenting the data in an easily accessible manner, is also described. The design decisions, challenges, and practical experiences from real-world large scale deployment...
Peak Load Regulation and Cost Optimization for Microgrids by Installing a Heat Storage Tank and a Portable Energy System

Directory of Open Access Journals (Sweden)

Hong Zhang

2018-04-01

Full Text Available With the rapid growth of electricity demands, many traditional distributed networks cannot cover their peak demands, especially in the evening. Additionally, with the interconnection of distributed electrical and thermal grids, system operational flexibility and energy efficiency can be affected as well. Therefore, by adding a portable energy system and a heat storage tank to the traditional distributed system, this paper proposes a newly defined distributed network to deal with the aforementioned problems. Simulation results show that by adding a portable energy system, fossil fuel energy consumption and daily operation cost can be reduced by 8% and 28.29%, respectively. Moreover, system peak load regulating capacity can be significantly improved. However, by introducing the portable energy system to the grid, system uncertainty can be increased to some extent. Therefore, chance constrained programming is proposed to control the system while considering system uncertainty. By applying Particle Swarm Optimization—Monte Carlo to solve the chance constrained programming, results show that power system economy and uncertainty can be compromised by selecting appropriate confidence levels α and β. It is also reported that by installing an extra heat storage tank, combined heat and power energy efficiency can be significantly improved and the installation capacity of the battery can be reduced.
Storage and transmission of secondary energy

International Nuclear Information System (INIS)

Taube, M.

1979-09-01

In the area of the total energy flow, possibilities and limits of shifts in time (storage) and in space (transfer) of secondary energy, i.e. electrical, chemical and thermal energy are examined and formulated. These shifts are linked to the qualitative conversions of secondary energy. The multiple technological possibilities, the spectrum of governing factors and the numerous technical and economical parameters show that only a complex optimization is possible. (Auth.)
Large temporal scale and capacity subsurface bulk energy storage with CO2

Science.gov (United States)

Saar, M. O.; Fleming, M. R.; Adams, B. M.; Ogland-Hand, J.; Nelson, E. S.; Randolph, J.; Sioshansi, R.; Kuehn, T. H.; Buscheck, T. A.; Bielicki, J. M.

2017-12-01

Decarbonizing energy systems by increasing the penetration of variable renewable energy (VRE) technologies requires efficient and short- to long-term energy storage. Very large amounts of energy can be stored in the subsurface as heat and/or pressure energy in order to provide both short- and long-term (seasonal) storage, depending on the implementation. This energy storage approach can be quite efficient, especially where geothermal energy is naturally added to the system. Here, we present subsurface heat and/or pressure energy storage with supercritical carbon dioxide (CO2) and discuss the system's efficiency, deployment options, as well as its advantages and disadvantages, compared to several other energy storage options. CO2-based subsurface bulk energy storage has the potential to be particularly efficient and large-scale, both temporally (i.e., seasonal) and spatially. The latter refers to the amount of energy that can be stored underground, using CO2, at a geologically conducive location, potentially enabling storing excess power from a substantial portion of the power grid. The implication is that it would be possible to employ centralized energy storage for (a substantial part of) the power grid, where the geology enables CO2-based bulk subsurface energy storage, whereas the VRE technologies (solar, wind) are located on that same power grid, where (solar, wind) conditions are ideal. However, this may require reinforcing the power grid's transmission lines in certain parts of the grid to enable high-load power transmission from/to a few locations.

Hybrid radical energy storage device and method of making

Science.gov (United States)

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

2015-01-27

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.
A Control Architecture to Coordinate Renewable Energy Sources and Energy Storage Systems in Islanded Microgrids

DEFF Research Database (Denmark)

Wu, Dan; Tang, Fen; Dragicevic, Tomislav

2015-01-01

Coordinated operation of microgrids requires that energy management system takes into account both the available power in renewable energy sources (RES) and storage capacity of energy storage systems (ESS). In this paper, a coordinated architecture of islanded AC microgrids with smooth switching...
Impact of wind farms with energy storage on transient stability

Science.gov (United States)

Bowman, Douglas Allen

Today's energy infrastructure will need to rapidly expand in terms of reliability and flexibility due to aging infrastructure, changing energy market conditions, projected load increases, and system reliability requirements. Over the few decades, several states in the U.S. are now requiring an increase in wind penetration. These requirements will have impacts on grid reliability given the inherent intermittency of wind generation and much research has been completed on the impact of wind on grid reliability. Energy storage has been proposed as a tool to provide greater levels of reliability; however, little research has occurred in the area of wind with storage and its impact on stability given different possible scenarios. This thesis addresses the impact of wind farm penetration on transient stability when energy storage is added. The results show that battery energy storage located at the wind energy site can improve the stability response of the system.
Integrated building energy systems design considering storage technologies

Energy Technology Data Exchange (ETDEWEB)

Stadler, Michael; Marnay, Chris; Lai, Judy; Aki, Hirohisa (Lawrence Berkeley National Laboratory (United States)). e-mail: MStadler@lbl.gov; Siddiqui, Afzal (Dept. of Statistical Science at Univ. College London (United Kingdom))

2009-07-01

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 CO{sub 2} 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 CO{sub 2} 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 project performed for the U.S. Dept. 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 CO{sub 2} minimization strategy where the common assumption that batteries can be charged by PV can be fulfilled at extraordinarily high energy costs for the site.
Integrated Building Energy Systems Design Considering Storage Technologies

International Nuclear Information System (INIS)

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

2009-01-01

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 project performed 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
Preliminary analytical study on the feasibility of using reinforced concrete pile foundations for renewable energy storage by compressed air energy storage technology

Science.gov (United States)

Tulebekova, S.; Saliyev, D.; Zhang, D.; Kim, J. R.; Karabay, A.; Turlybek, A.; Kazybayeva, L.

2017-11-01

Compressed air energy storage technology is one of the promising methods that have high reliability, economic feasibility and low environmental impact. Current applications of the technology are mainly limited to energy storage for power plants using large scale underground caverns. This paper explores the possibility of making use of reinforced concrete pile foundations to store renewable energy generated from solar panels or windmills attached to building structures. The energy will be stored inside the pile foundation with hollow sections via compressed air. Given the relatively small volume of storage provided by the foundation, the required storage pressure is expected to be higher than that in the large-scale underground cavern. The high air pressure typically associated with large temperature increase, combined with structural loads, will make the pile foundation in a complicated loading condition, which might cause issues in the structural and geotechnical safety. This paper presents a preliminary analytical study on the performance of the pile foundation subjected to high pressure, large temperature increase and structural loads. Finite element analyses on pile foundation models, which are built from selected prototype structures, have been conducted. The analytical study identifies maximum stresses in the concrete of the pile foundation under combined pressure, temperature change and structural loads. Recommendations have been made for the use of reinforced concrete pile foundations for renewable energy storage.
Filtering and storage working memory networks in younger and older age.

Science.gov (United States)

Vellage, Anne-Katrin; Becke, Andreas; Strumpf, Hendrik; Baier, Bernhard; Schönfeld, Mircea Ariel; Hopf, Jens-Max; Müller, Notger G

2016-11-01

Working memory (WM) is a multi-component model that among others involves the two processes of filtering and storage. The first reflects the necessity to inhibit irrelevant information from entering memory, whereas the latter refers to the active maintenance of object representations in memory. In this study, we aimed at a) redefining the neuronal networks sustaining filtering and storage within visual working memory by avoiding shortcomings of prior studies, and b) assessing age-related changes in these networks. We designed a new paradigm that strictly controlled for perceptual load by presenting the same number of stimuli in each of three conditions. We calculated fMRI contrasts between a baseline condition (low filter and low storage load) and conditions that posed high demands on filtering and storage, respectively, in large samples of younger ( n = 40) and elder ( n = 38) participants. Our approach of comparing contrasts between groups revealed more extensive filter and storage WM networks than previous studies. In the younger group, filtering involved the bilateral insulae, the right occipital cortex, the right brainstem, and the right cerebellum. In the elder group, filtering was associated with the bilateral insulae, right precuneus, and bilateral ventromedial prefrontal cortex. An extensive neuronal network was also found during storage of information in the bilateral posterior parietal cortex, the left ventromedial prefrontal cortex, and the right precuneus in the younger participants. In addition to these brain regions, elder participants recruited the bilateral ventral prefrontal cortex, the superior, middle and inferior and temporal cortex, the left cingulum and the bilateral parahippocampal cortex. In general, elder participants recruited more brain regions in comparison to younger participants to reach similar accuracy levels. Furthermore, in elder participants one brain region emerged in both contrasts, namely the left ventromedial prefrontal
A review on phase change energy storage: materials and applications

International Nuclear Information System (INIS)

Farid, Mohammed M.; Khudhair, Amar M.; Razack, Siddique Ali K.; Al-Hallaj, Said

2004-01-01

Latent heat storage is one of the most efficient ways of storing thermal energy. Unlike the sensible heat storage method, the latent heat storage method provides much higher storage density, with a smaller temperature difference between storing and releasing heat. This paper reviews previous work on latent heat storage and provides an insight to recent efforts to develop new classes of phase change materials (PCMs) for use in energy storage. Three aspects have been the focus of this review: PCM materials, encapsulation and applications. There are large numbers of phase change materials that melt and solidify at a wide range of temperatures, making them attractive in a number of applications. Paraffin waxes are cheap and have moderate thermal energy storage density but low thermal conductivity and, hence, require large surface area. Hydrated salts have larger energy storage density and higher thermal conductivity but experience supercooling and phase segregation, and hence, their application requires the use of some nucleating and thickening agents. The main advantages of PCM encapsulation are providing large heat transfer area, reduction of the PCMs reactivity towards the outside environment and controlling the changes in volume of the storage materials as phase change occurs. The different applications in which the phase change method of heat storage can be applied are also reviewed in this paper. The problems associated with the application of PCMs with regards to the material and the methods used to contain them are also discussed
Engineered Nanomaterials for Energy Harvesting and Storage Applications

Science.gov (United States)

Gullapalli, Hemtej

Energy harvesting and storage are independent mechanisms, each having their own significance in the energy cycle. Energy is generally harvested from temperature variations, mechanical vibrations and other phenomena which are inherently sporadic in nature, harvested energy stands a better chance of efficient utilization if it can be stored and used later, depending on the demand. In essence a comprehensive device that can harness power from surrounding environment and provide a steady and reliable source of energy would be ideal. Towards realizing such a system, for the harvesting component, a piezoelectric nano-composite material consisting of ZnO nanostructures embedded into the matrix of 'Paper' has been developed. Providing a flexible backbone to a brittle material makes it a robust architecture. Energy harvesting by scavenging both mechanical and thermal fluctuations using this flexible nano-composite is discussed in this thesis. On the energy storage front, Graphene based materials developed with a focus towards realizing ultra-thin lithium ion batteries and supercapacitors are introduced. Efforts for enhancing the energy storage performance of such graphitic carbon are detailed. Increasing the rate capability by direct CVD synthesis of graphene on current collectors, enhancing its electrochemical capacity through doping and engineering 3D metallic structures to increase the areal energy density have been studied.
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.
Optimizing Storage and Renewable Energy Systems with REopt

Energy Technology Data Exchange (ETDEWEB)

Elgqvist, Emma M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Anderson, Katherine H. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cutler, Dylan S. [National Renewable Energy Lab. (NREL), Golden, CO (United States); DiOrio, Nicholas A. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Laws, Nicholas D. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Olis, Daniel R. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Walker, H. A. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2017-12-27

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

International Nuclear Information System (INIS)

Facci, Andrea L.; Sánchez, David; Jannelli, Elio; Ubertini, Stefano

2015-01-01

Highlights: • The trigenerative-CAES concept is introduced. • The thermodynamic feasibility of the trigenerative-CAES is assessed. • The effects of the relevant parameter on the system performances are dissected. • Technological issues on the trigenerative-CAES are highlighted. - Abstract: Energy storage is a cutting edge front for renewable and sustainable energy research. In fact, a massive exploitation of intermittent renewable sources, such as wind and sun, requires the introduction of effective mechanical energy storage systems. In this paper we introduce the concept of a trigenerative energy storage based on a compressed air system. The plant in study is a simplified design of the adiabatic compressed air energy storage and accumulates mechanical and thermal (both hot and cold) energy at the same time. We envisage the possibility to realize a relatively small size trigenerative compressed air energy storage to be placed close to the energy demand, according to the distributed generation paradigm. Here, we describe the plant concept and we identify all the relevant parameters influencing its thermodynamic behavior. Their effects are dissected through an accurate thermodynamic model. The most relevant technological issues, such as the guidelines for a proper choice of the compressor, expander and heat exchangers are also addressed. Our results show that T-CAES may have an interesting potential as a distributed system that combines electricity storage with heat and cooling energy production. We also show that the performances are significantly influenced by some operating and design parameters, whose feasibility in real applications must be considered.
Hydropower Storage May be the Key to Sustainable Energy

International Nuclear Information System (INIS)

Lemperiere, F.

2009-01-01

An analysis of future energy needs and sources should avoid utopias, clearly evaluate the needs, and quantify the potential, cost and impacts of possible solutions. Before mid century, the world will use three times the energy resources it presently requires. Most should be from renewable sources, and mainly through electricity. As the main renewable electricity sources are intermittent, some energy storage will be necessary: onshore or offshore pumped storage plants based on well proven technologies are a relevant cost-effective solution. Further needs that evolve as the century progresses might be met from solar energy or new nuclear solutions. Beyond their impact on climate change, large investments in various renewable energies and relevant storage may well be economically justified in most countries. This would also reduce the huge risk of conflict for fossil fuel control
The CUNY Energy Institute Electrical Energy Storage Development for Grid Applications

Energy Technology Data Exchange (ETDEWEB)

Banerjee, Sanjoy

2013-03-31

1. Project Objectives The objectives of the project are to elucidate science issues intrinsic to high energy density electricity storage (battery) systems for smart-grid applications, research improvements in such systems to enable scale-up to grid-scale and demonstrate a large 200 kWh battery to facilitate transfer of the technology to industry. 2. Background Complex and difficult to control interfacial phenomena are intrinsic to high energy density electrical energy storage systems, since they are typically operated far from equilibrium. One example of such phenomena is the formation of dendrites. Such dendrites occur on battery electrodes as they cycle, and can lead to internal short circuits, reducing cycle life. An improved understanding of the formation of dendrites and their control can improve the cycle life and safety of many energy storage systems, including rechargeable lithium and zinc batteries. Another area where improved understanding is desirable is the application of ionic liquids as electrolytes in energy storage systems. An ionic liquid is typically thought of as a material that is fully ionized (consisting only of anions and cations) and is fluid at or near room temperature. Some features of ionic liquids include a generally high thermal stability (up to 450 °C), a high electrochemical window (up to 6 V) and relatively high intrinsic conductivities. Such features make them attractive as battery or capacitor electrolytes, and may enable batteries which are safer (due to the good thermal stability) and of much higher energy density (due to the higher voltage electrode materials which may be employed) than state of the art secondary (rechargeable) batteries. Of particular interest is the use of such liquids as electrolytes in metal air batteries, where energy densities on the order of 1-2,000 Wh / kg are possible; this is 5-10 times that of existing state of the art lithium battery technology. The Energy Institute has been engaged in the
Market and policy barriers to energy storage deployment :

Energy Technology Data Exchange (ETDEWEB)

Bhatnagar, Dhruv; Currier, Aileen B.; Hernandez, Jacquelynne; Ma, Ookie; Kirby, Brendan

2013-09-01

Electric energy storage technologies have recently been in the spotlight, discussed as essential grid assets that can provide services to increase the reliability and resiliency of the grid, including furthering the integration of variable renewable energy resources. Though they can provide numerous grid services, there are a number of factors that restrict their current deployment. The most significant barrier to deployment is high capital costs, though several recent deployments indicate that capital costs are decreasing and energy storage may be the preferred economic alternative in certain situations. However, a number of other market and regulatory barriers persist, limiting further deployment. These barriers can be categorized into regulatory barriers, market (economic) barriers, utility and developer business model barriers, crosscutting barriers and technology barriers. This report, through interviews with stakeholders and review of regulatory filings in four regions roughly representative of the United States, identifies the key barriers restricting further energy storage development in the country. The report also includes a discussion of possible solutions to address these barriers and a review of initiatives around the country at the federal, regional and state levels that are addressing some of these issues. Energy storage could have a key role to play in the future grid, but market and regulatory issues have to be addressed to allow storage resources open market access and compensation for the services they are capable of providing. Progress has been made in this effort, but much remains to be done and will require continued engagement from regulators, policy makers, market operators, utilities, developers and manufacturers.
The viability of balancing wind generation with large scale energy storage

International Nuclear Information System (INIS)

Nyamdash, Batsaikhan; Denny, Eleanor; O'Malley, Mark

2010-01-01

This paper studies the impact of combining wind generation and dedicated large scale energy storage on the conventional thermal plant mix and the CO 2 emissions of a power system. Different strategies are proposed here in order to explore the best operational strategy for the wind and storage system in terms of its effect on the net load. Furthermore, the economic viability of combining wind and large scale storage is studied. The empirical application, using data for the Irish power system, shows that combined wind and storage reduces the participation of mid-merit plants and increases the participation of base-load plants. Moreover, storage negates some of the CO 2 emissions reduction of the wind generation. It was also found that the wind and storage output can significantly reduce the variability of the net load under certain operational strategies and the optimal strategy depends on the installed wind capacity. However, in the absence of any supporting mechanism none of the storage devices were economically viable when they were combined with the wind generation on the Irish power system. - Research Highlights: → Energy storage would displace the peaking and mid-merit plants generations by the base-load plants generations. Energy storage may negate the CO 2 emissions reduction that is due to the increased wind generations. →Energy storage reduces the variation of the net load. →Under certain market conditions, merchant type energy storage is not viable.
Benefits from flywheel energy storage for area regulation in California - demonstration results : a study for the DOE Energy Storage Systems program.

Energy Technology Data Exchange (ETDEWEB)

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

2009-10-01

This report documents a high-level analysis of the benefit and cost for flywheel energy storage used to provide area regulation for the electricity supply and transmission system in California. Area regulation is an 'ancillary service' needed for a reliable and stable regional electricity grid. The analysis was based on results from a demonstration, in California, of flywheel energy storage developed by Beacon Power Corporation (the system's manufacturer). Demonstrated was flywheel storage systems ability to provide 'rapid-response' regulation. Flywheel storage output can be varied much more rapidly than the output from conventional regulation sources, making flywheels more attractive than conventional regulation resources. The performance of the flywheel storage system demonstrated was generally consistent with requirements for a possible new class of regulation resources - 'rapid-response' energy-storage-based regulation - in California. In short, it was demonstrated that Beacon Power Corporation's flywheel system follows a rapidly changing control signal (the ACE, which changes every four seconds). Based on the results and on expected plant cost and performance, the Beacon Power flywheel storage system has a good chance of being a financially viable regulation resource. Results indicate a benefit/cost ratio of 1.5 to 1.8 using what may be somewhat conservative assumptions. A benefit/cost ratio of one indicates that, based on the financial assumptions used, the investment's financial returns just meet the investors target.
Zero Energy Communities with Central Solar Plants using Liquid Desiccants and Local Storage: Preprint

Energy Technology Data Exchange (ETDEWEB)

Burch, J.; Woods, J.; Kozubal, E.; Boranian, A.

2012-08-01

The zero energy community considered here consists of tens to tens-of-thousands of residences coupled to a central solar plant that produces all the community's electrical and thermal needs. A distribution network carries fluids to meet the heating and cooling loads. Large central solar systems can significantly reduce cost of energy vs. single family systems, and they enable economical seasonal heat storage. However, the thermal distribution system is costly. Conventional district heating/cooling systems use a water/glycol solution to deliver sensible energy. Piping is sized to meet the peak instantaneous load. A new district system introduced here differs in two key ways: (i) it continuously distributes a hot liquid desiccant (LD) solution to LD-based heating and cooling equipment in each home; and (ii) it uses central and local storage of both LD and heat to reduce flow rates to meet average loads. Results for piping sizes in conventional and LD thermal communities show that the LD zero energy community reduces distribution piping diameters meeting heating loads by {approx}5X and meeting cooling loads by {approx}8X for cooling, depending on climate.
Thermal energy storage for smart grid applications

Science.gov (United States)

Al-Hallaj, Said; Khateeb, Siddique; Aljehani, Ahmed; Pintar, Mike

2018-01-01

Energy consumption for commercial building cooling accounts for 15% of all commercial building's electricity usage [1]. Electric utility companies charge their customers time of use consumption charges (/kWh) and additionally demand usage charges (/kW) to limit peak energy consumption and offset their high operating costs. Thus, there is an economic incentive to reduce both the electricity consumption charges and demand charges by developing new energy efficient technologies. Thermal energy storage (TES) systems using a phase change material (PCM) is one such technology that can reduce demand charges and shift the demand from on-peak to off-peak rates. Ice and chilled water have been used in thermal storage systems for many decades, but they have certain limitations, which include a phase change temperature of 0 degrees Celsius and relatively low thermal conductivity in comparison to other materials, which limit their applications as a storage medium. To overcome these limitations, a novel phase change composite (PCC) TES material was developed that has much higher thermal conductivity that significantly improves the charge / discharge rate and a customizable phase change temperature to allow for better integration with HVAC systems. Compared to ice storage, the PCC TES system is capable of very high heat transfer rate and has lower system and operational costs. Economic analysis was performed to compare the PCC TES system with ice system and favorable economics was proven. A 4.5 kWh PCC TES prototype system was also designed for testing and validation purpose.
Optimal control, investment and utilization schemes for energy storage under uncertainty

Science.gov (United States)

Mirhosseini, Niloufar Sadat

Energy storage has the potential to offer new means for added flexibility on the electricity systems. This flexibility can be used in a number of ways, including adding value towards asset management, power quality and reliability, integration of renewable resources and energy bill savings for the end users. However, uncertainty about system states and volatility in system dynamics can complicate the question of when to invest in energy storage and how best to manage and utilize it. This work proposes models to address different problems associated with energy storage within a microgrid, including optimal control, investment, and utilization. Electric load, renewable resources output, storage technology cost and electricity day-ahead and spot prices are the factors that bring uncertainty to the problem. A number of analytical methodologies have been adopted to develop the aforementioned models. Model Predictive Control and discretized dynamic programming, along with a new decomposition algorithm are used to develop optimal control schemes for energy storage for two different levels of renewable penetration. Real option theory and Monte Carlo simulation, coupled with an optimal control approach, are used to obtain optimal incremental investment decisions, considering multiple sources of uncertainty. Two stage stochastic programming is used to develop a novel and holistic methodology, including utilization of energy storage within a microgrid, in order to optimally interact with energy market. Energy storage can contribute in terms of value generation and risk reduction for the microgrid. The integration of the models developed here are the basis for a framework which extends from long term investments in storage capacity to short term operational control (charge/discharge) of storage within a microgrid. In particular, the following practical goals are achieved: (i) optimal investment on storage capacity over time to maximize savings during normal and emergency

The value of co-locating energy storage with wind resources

Energy Technology Data Exchange (ETDEWEB)

Fox, C. [Victoria Univ., BC (Canada). Inst. for Integrated Energy Systems

2010-07-01

This PowerPoint presentation discussed the value of wind energy storage systems. The systems can be used to downsize transmission requirements and to minimize reliability and forecast uncertainty. Revenue factors in relation to wind power energy storage are determined by the amount of wind power produced each hour with the wind farm capacity and hourly electricity price. Case studies of a wind farm in Ontario over a period of 20 years were used to determine capacity and revenue factors as well as gross revenues. The maximum revenue factor was determined by multiplying the greatest wind energy output by the highest electricity prices. A hybrid wind farm energy storage system was designed to determine energy storage discharges and charges to and from the grid at pool prices. The method allowed for time-shifts in wind generation resources and downsized transmission requirements for remote resources. The mixed integer linear program model co-optimized revenues from the wind farm and the energy storage facility. Combined output was constrained to the transmission capacity. Transmission losses were neglected, and capital costs were considered. Future studies are needed to determine levelized electricity costs under different load growth scenarios. tabs., figs.
Mesoporous NiCo2O4 nano-needles supported by 3D interconnected carbon network on Ni foam for electrochemical energy storage

Science.gov (United States)

Lu, Congxiang; Liu, Wen-wen; Pan, Hui; Tay, Beng Kang; Wang, Xingli; Liang, Kun; Wei, Xuezhe

2018-05-01

In this work, a three dimensional (3D) interconnected carbon network consisting of ultrathin graphite (UG) and carbon nanotubes (CNTs) on Ni foam is fabricated and employed as a novel type of substrate for mesoporous NiCo2O4 nano-needles. The successfully synthesized NiCo2O4 nano-needles/CNTs/UG on Ni foam has many advantages including facile electrolyte access and direct conducting pathways towards current collectors, which enable it to be a promising electrode material in battery-like electrochemical energy storage. Encouragingly, a high capacity of 135.1 mAh/g at the current density of 1 A/g, superior rate performance and also stable cycling for 1200 cycles at the current density of 5 A/g have been demonstrated in this novel material.
Performance and cost of energy transport and storage systems for dish applications using reversible chemical reactions

Science.gov (United States)

Schredder, J. M.; Fujita, T.

1984-01-01

The use of reversible chemical reactions for energy transport and storage for parabolic dish networks is considered. Performance and cost characteristics are estimated for systems using three reactions (sulfur-trioxide decomposition, steam reforming of methane, and carbon-dioxide reforming of methane). Systems are considered with and without storage, and in several energy-delivery configurations that give different profiles of energy delivered versus temperature. Cost estimates are derived assuming the use of metal components and of advanced ceramics. (The latter reduces the costs by three- to five-fold). The process that led to the selection of the three reactions is described, and the effects of varying temperatures, pressures, and heat exchanger sizes are addressed. A state-of-the-art survey was performed as part of this study. As a result of this survey, it appears that formidable technical risks exist for any attempt to implement the systems analyzed in this study, especially in the area of reactor design and performance. The behavior of all components and complete systems under thermal energy transients is very poorly understood. This study indicates that thermochemical storage systems that store reactants as liquids have efficiencies below 60%, which is in agreement with the findings of earlier investigators.
Homogeneous/Inhomogeneous-Structured Dielectrics and their Energy-Storage Performances.

Science.gov (United States)

Yao, Zhonghua; Song, Zhe; Hao, Hua; Yu, Zhiyong; Cao, Minghe; Zhang, Shujun; Lanagan, Michael T; Liu, Hanxing

2017-05-01

The demand for dielectric capacitors with higher energy-storage capability is increasing for power electronic devices due to the rapid development of electronic industry. Existing dielectrics for high-energy-storage capacitors and potential new capacitor technologies are reviewed toward realizing these goals. Various dielectric materials with desirable permittivity and dielectric breakdown strength potentially meeting the device requirements are discussed. However, some significant limitations for current dielectrics can be ascribed to their low permittivity, low breakdown strength, and high hysteresis loss, which will decrease their energy density and efficiency. Thus, the implementation of dielectric materials for high-energy-density applications requires the comprehensive understanding of both the materials design and processing. The optimization of high-energy-storage dielectrics will have far-reaching impacts on the sustainable energy and will be an important research topic in the near future. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
A Novel Constant-Pressure Pumped Hydro Combined with Compressed Air Energy Storage System

Directory of Open Access Journals (Sweden)

Erren Yao

2014-12-01

Full Text Available As intermittent renewable energy is receiving increasing attention, the combination of intermittent renewable energy with large-scale energy storage technology is considered as an important technological approach for the wider application of wind power and solar energy. Pumped hydro combined with compressed air energy storage system (PHCA is one of the energy storage systems that not only integrates the advantages but also overcomes the disadvantages of compressed air energy storage (CAES systems and pumped hydro energy storage systems to solve the problem of energy storage in China’s arid regions. Aiming at the variable working conditions of PHCA system technology, this study proposes a new constant-pressure PHCA. The most significant characteristics of this system were that the water pump and hydroturbine work under stable conditions and this improves the working efficiency of the equipment without incurring an energy loss. In addition, the constant-pressure PHCA system was subjected to energy and exergy analysis, in expectation of exploring an attractive solution for the large-scale storage of existing intermittent renewable energy.
Carbon Nanotubes as Future Energy Storage System

OpenAIRE

Vasu , V; Silambarasan , D

2017-01-01

International audience; Hydrogen is considered to be a clean energy carrier. At present the main drawback in using hydrogen as the fuel is the lack of proper hydrogen storage vehicle, thus ongoing research is focused on the development of advance hydrogen storage materials. Many alloys are able to store hydrogen reversibly, but the gravimetric storage density is too low for any practical applications. Theoretical studies have predicted that interaction of hydrogen with carbon nanotubes is by ...
Preparation of shape-stabilized co-crystallized poly (ethylene glycol) composites as thermal energy storage materials

International Nuclear Information System (INIS)

Qian, Yong; Wei, Ping; Jiang, Pingkai; Li, Zhi; Yan, Yonggang; Ji, Kejian; Deng, Weihua

2013-01-01

Highlights: • Shape-stabilized PEG composites were prepared by sol–gel process. • The increased energy storage ability of composite was from cocrystallization effect. • Diammonium phosphate improved flame retardancy properties of PEG composite. • PEG composites had potential to be used as thermal energy storage materials. - Abstract: Shape-stabilized co-crystallized poly (ethylene glycol) (PEG) composites were prepared by sol–gel process. Tetraethoxysilane was utilized as supporting matrix precursor. The crystallization property as well as thermal energy storage properties of PEG was influenced by silica network. The combination of PEG 2k and PEG 10k with suitable ratio (3:1 by weight) led to synergistically increased fusion enthalpy attributed to cocrystallization effect. Furthermore, halogen-free flame retarded PEG composites were obtained using diammonium phosphate as flame retardant. With suitable composition, the latent heat value of flame retarded PEG composite was 96.7 kJ/kg accompanied with good thermal stability and improved flame retardancy properties. Fourier transform infrared spectrum (FT-IR), X-ray diffraction (XRD), polarized optical microscope (POM) and scanning electron microscope (SEM) were used to characterize the structure of PEG composites. Thermal stability properties of PEG composites were investigated by thermogravimetric analyzer (TGA). Char residue obtained from muffle furnace of PEG composites was analyzed by SEM and FT-IR. Flame retardancy properties of PEG composites were estimated by pyrolysis combustion flow calorimeter. Results showed that it was potential for shape-stabilized halogen-free flame retarded PEG composite to be applied in thermal energy storage field
Fiber-shaped energy harvesting and storage devices

CERN Document Server

Peng, Huisheng

2015-01-01

This comprehensive book covers flexible fiber-shaped devices in the area of energy conversion and storage. The first part of the book introduces recently developed materials, particularly, various nanomaterials and composite materials based on nanostructured carbon such as carbon nanotubes and graphene, metals and polymers for the construction of fiber electrodes. The second part of the book focuses on two typical twisted and coaxial architectures of fiber-shaped devices for energy conversion and storage. The emphasis is placed on dye-sensitized solar cells, polymer solar cells, lithium-ion b
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.
Energy efficiency networks; Energieeffizienz-Netzwerke

Energy Technology Data Exchange (ETDEWEB)

Gruber, Anna [Forschungsgesellschaft fuer Energiewirtschaft mbH (FfE GmbH), Muenchen (Germany)

2011-07-01

Energy efficiency networks are an attractive method to increase the energy efficiency and to reduce the costs and CO{sub 2} emissions of the companies operating in this network. A special feature of the energy efficiency networks is the exchange of experiences and training of the energy managers. Energy efficiency networks consist of about ten to fifteen locally domiciled companies. During the project period of three to four years, there are two main phases. In the first phase, the initial consultation phase, the actual state of a company is captured, and measures to increase the efficiency and energy conservation are identified. Parallel to this, in the second phase every three months a meeting with the participating companies takes place. Experience exchange and implementation of energy efficiency measures are the focus of these meetings. Initial studies show that the increase of the energy efficiency during participating in the energy efficiency network almost can be doubled in comparison to the average of the industry.
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
Microwavable thermal energy storage material

Science.gov (United States)

Salyer, I.O.

1998-09-08

A microwavable thermal energy storage material is provided which includes a mixture of a phase change material and silica, and a carbon black additive in the form of a conformable dry powder of phase change material/silica/carbon black, or solid pellets, films, fibers, moldings or strands of phase change material/high density polyethylene/ethylene vinyl acetate/silica/carbon black which allows the phase change material to be rapidly heated in a microwave oven. The carbon black additive, which is preferably an electrically conductive carbon black, may be added in low concentrations of from 0.5 to 15% by weight, and may be used to tailor the heating times of the phase change material as desired. The microwavable thermal energy storage material can be used in food serving applications such as tableware items or pizza warmers, and in medical wraps and garments. 3 figs.
MAXIMIZING MAGNETIC ENERGY STORAGE IN THE SOLAR CORONA

International Nuclear Information System (INIS)

Wolfson, Richard; Drake, Christina; Kennedy, Max

2012-01-01

The energy that drives solar eruptive events such as coronal mass ejections (CMEs) almost certainly originates in coronal magnetic fields. Such energy may build up gradually on timescales of days or longer before its sudden release in an eruptive event, and the presence of free magnetic energy capable of rapid release requires nonpotential magnetic fields and associated electric currents. For magnetic energy to power a CME, that energy must be sufficient to open the magnetic field to interplanetary space, to lift the ejecta against solar gravity, and to accelerate the material to speeds of typically several hundred km s –1 . Although CMEs are large-scale structures, many originate from relatively compact active regions on the solar surface—suggesting that magnetic energy storage may be enhanced when it takes place in smaller magnetic structures. This paper builds on our earlier work exploring energy storage in large-scale dipolar and related bipolar magnetic fields. Here we consider two additional cases: quadrupolar fields and concentrated magnetic bipoles intended to simulate active regions. Our models yield stored energies whose excess over that of the corresponding open field state can be greater than 100% of the associated potential field energy; this contrasts with maximum excess energies of only about 20% for dipolar and symmetric bipolar configurations. As in our previous work, energy storage is enhanced when we surround a nonpotential field with a strong overlying potential field that acts to 'hold down' the nonpotential flux as its magnetic energy increases.
Energy storage by compressed air. [using windpowered pumps

Science.gov (United States)

Szego, G. C.

1973-01-01

The feasibility of windpower energy storage by compressed air is considered. The system is comprised of a compressor, a motor, and a pump turbine to store air in caverns or aquifiers. It is proposed that storage of several days worth of compressed air up to 650 pounds per square inch can be used to push the aquifier up closer to the container dome and thus initiate piston action by simply compressing air more and more. More energy can be put into it by pressure increase or pushing back the water in the aquifier. This storage system concept has reheat flexibility and lowest cost effectiveness.
Technoeconomic Modeling of Battery Energy Storage in SAM

Energy Technology Data Exchange (ETDEWEB)

DiOrio, Nicholas [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dobos, Aron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Janzou, Steven [National Renewable Energy Lab. (NREL), Golden, CO (United States); Nelson, Austin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lundstrom, Blake [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-09-01

Detailed comprehensive lead-acid and lithium-ion battery models have been integrated with photovoltaic models in an effort to allow System Advisor Model (SAM) to offer the ability to predict the performance and economic benefit of behind the meter storage. In a system with storage, excess PV energy can be saved until later in the day when PV production has fallen, or until times of peak demand when it is more valuable. Complex dispatch strategies can be developed to leverage storage to reduce energy consumption or power demand based on the utility rate structure. This document describes the details of the battery performance and economic models in SAM.
Outstanding Li-storage performance of LiFePO4@MWCNTs cathode material with 3D network structure for lithium-ion batteries

Science.gov (United States)

Sun, Xiaodong; Zhang, Le

2018-05-01

In this work, the MWCNTs-decorated LiFePO4 microspheres (LiFePO4@MWCNTs) with a 3D network structure have been synthesized by a facile and efficient spray-drying approach followed by solid-state reaction in a reduction atmosphere. In the as-prepared composite, the MWCNTs around LiFePO4 nanoparticles can provide 3D conductive networks which greatly facilitate the transport of Li+-ion and electron during the electrochemical reaction. Compared to the pure LiFePO4 material, the LiFePO4@MWCNTs composite as cathode for lithium-ion batteries exhibits significantly improved Li-storage performance in terms of rate capability and cyclic stability. Therefore, we can speculate that the spray-drying approach is a promising route to prepare the high-performance electrode materials with 3D network structure for electrochemical energy storage.
Reducing a cortical network to a Potts model yields storage capacity estimates

Science.gov (United States)

Naim, Michelangelo; Boboeva, Vezha; Kang, Chol Jun; Treves, Alessandro

2018-04-01

An autoassociative network of Potts units, coupled via tensor connections, has been proposed and analysed as an effective model of an extensive cortical network with distinct short- and long-range synaptic connections, but it has not been clarified in what sense it can be regarded as an effective model. We draw here the correspondence between the two, which indicates the need to introduce a local feedback term in the reduced model, i.e. in the Potts network. An effective model allows the study of phase transitions. As an example, we study the storage capacity of the Potts network with this additional term, the local feedback w, which contributes to drive the activity of the network towards one of the stored patterns. The storage capacity calculation, performed using replica tools, is limited to fully connected networks, for which a Hamiltonian can be defined. To extend the results to the case of intermediate partial connectivity, we also derive the self-consistent signal-to-noise analysis for the Potts network; and finally we discuss the implications for semantic memory in humans.
Selection of materials with potential in sensible thermal energy storage

International Nuclear Information System (INIS)

Fernandez, A.I.; Martinez, M.; Segarra, M.; Martorell, I.; Cabeza, L.F.

2010-01-01

Thermal energy storage is a technology under investigation since the early 1970s. Since then, numerous new applications have been found and much work has been done to bring this technology to the market. Nevertheless, the materials used either for latent or for sensible storage were mostly investigated 30 years ago, and the research has lead to improvement in their performance under different conditions of applications. In those years a significant number of new materials were developed in many fields other than storage and energy, but a great effort to characterize and classify these materials was done. Taking into account the fact that thousands of materials are known and a large number of new materials are developed every year, the authors use the methodology for materials selection developed by Prof. Ashby to give an overview of other materials suitable to be used in thermal energy storage. Sensible heat storage at temperatures between 150 and 200 C is defined as a case study and two different scenarios were considered: long term sensible heat storage and short term sensible heat storage. (author)
High temperature underground thermal energy storage system for solar energy

Science.gov (United States)

Collins, R. E.

1980-01-01

The activities feasibility of high temperature underground thermal storage of energy was investigated. Results indicate that salt cavern storage of hot oil is both technically and economically feasible as a method of storing huge quantities of heat at relatively low cost. One particular system identified utilizes a gravel filled cavern leached within a salt dome. Thermal losses are shown to be less than one percent of cyclically transferred heat. A system like this having a 40 MW sub t transfer rate capability and over eight hours of storage capacity is shown to cost about $13.50 per KWh sub t.
储能技术研究景观辨识及演化探析%Identifying the Landscape and Its Evolution in Energy Storage Research

Institute of Scientific and Technical Information of China (English)

刘娜; 孙静林; 毛荐其

2017-01-01

This study seeks to integrate statistics, text mining, burst detecting and co-occurrence network visualiza-tion to identify the landscape and its evolution of energy storage research from a holistic perspective based on ar-ticles on physical, chemical, electromagnetic and phase change energy storage extracted from SCI-E and SSCI data-base between 1991 and 2015. A stability coefficient and an innovation coefficient are also defined to measure the stability evolution and innovation evolution of keywords co-occurrence networks in energy storage respectively. Our results indicate that the research in energy storage is highly-concentrated in key issues, hot topics are fly-wheel, lithium ion batteries, supercapacitors and phase change materials, and frontier topics are compressed air energy storage, energy storage, lithium ion batteries, thermal conductivity and thermal energy storage. We also find keywords co-occurrence networks expand significantly, knowledge structures evolve constantly and energy storage research is still in its innovation phase.%基于SCI-E及SSCI数据库,检索并提取1991—2015年间物理储能、化学储能、电磁储能和相变储能4大技术领域的论文数据,试图整合统计分析、文本挖掘、突现检测算法和共现网络可视化方法,旨在从整体视角实现对4大储能技术领域科学研究景观的辨识及演化探析.此外,还定义了稳定系数和创新系数,以测度储能关键词共现网络的稳定性演化和创新性演化.研究发现:储能领域的研究问题是高度集中的,"飞轮"、"锂离子电池"、"超级电容器"和"相变材料"是研究热点,"压缩空气储能"、"能源存储"、"锂离子电池"、"导热性"和"热发电"是研究前沿;储能关键词共现网络扩张明显,知识结构也不断演化,储能研究仍处于创新热络期.

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.)
Graphene-Based Carbon Materials for Electrochemical Energy Storage

Directory of Open Access Journals (Sweden)

Fei Liu

2013-01-01

Full Text Available Because of their unique 2D structure and numerous fascinating properties, graphene-based materials have attracted particular attention for their potential applications in energy storage devices. In this review paper, we focus on the latest work regarding the development of electrode materials for batteries and supercapacitors from graphene and graphene-based carbon materials. To begin, the advantages of graphene as an electrode material and the existing problems facing its use in this application will be discussed. The next several sections deal with three different methods for improving the energy storage performance of graphene: the restacking of the nanosheets, the doping of graphene with other elements, and the creation of defects on graphene planes. State-of-the-art work is reviewed. Finally, the prospects and further developments in the field of graphene-based materials for electrochemical energy storage are discussed.
Robust energy storage scheduling for imbalance reduction of strategically formed energy balancing groups

International Nuclear Information System (INIS)

Chakraborty, Shantanu; Okabe, Toshiya

2016-01-01

Imbalance (on-line energy gap between contracted supply and actual demand, and associated cost) reduction is going to be a crucial service for a Power Producer and Supplier (PPS) in the deregulated energy market. PPS requires forward market interactions to procure energy as precisely as possible in order to reduce imbalance energy. This paper presents, 1) (off-line) an effective demand aggregation based strategy for creating a number of balancing groups that leads to higher predictability of group-wise aggregated demand, 2) (on-line) a robust energy storage scheduling that minimizes the imbalance energy and cost of a particular balancing group considering the demand prediction uncertainty. The group formation is performed by a Probabilistic Programming approach using Bayesian Markov Chain Monte Carlo (MCMC) method after applied on the historical demand statistics. Apart from the group formation, the aggregation strategy (with the help of Bayesian Inference) also clears out the upper-limit of the required storage capacity for a formed group, fraction of which is to be utilized in on-line operation. For on-line operation, a robust energy storage scheduling method is proposed that minimizes expected imbalance energy and cost (a non-linear function of imbalance energy) while incorporating the demand uncertainty of a particular group. The proposed methods are applied on the real apartment buildings' demand data in Tokyo, Japan. Simulation results are presented to verify the effectiveness of the proposed methods. - Highlights: • Strategic method for intelligent energy balancing group formation using Bayesian MCMC. • Stochastic programming based robust and online energy storage (battery) scheduling. • Imbalance cost (regulation) and energy reduction of a balancing group. • Imbalance cost reduction of 80% attainable by considerably lower battery capacity.
Economic feasibility of thermal energy storage systems

Energy Technology Data Exchange (ETDEWEB)

Habeebullah, B.A. [Faculty of Engineering, King Abdulaziz University, Jeddah (Saudi Arabia)

2007-07-01

This paper investigates the economic feasibility of both building an ice thermal storage and structure a time of rate tariff for the unique air conditioning (A/C) plant of the Grand Holy Mosque of Makkah, Saudi Arabia. The features of the building are unique where the air-conditioned 39,300 m{sup 2} zone is open to the atmosphere and the worshippers fully occupy the building five times a day, in addition hundreds of thousands of worshippers attend the blessed weekend's prayer at noontime, which escalates the peak electricity load. For economic analysis, the objective function is the daily electricity bill that includes the operation cost and the capital investment of the ice storage system. The operation cost is function of the energy imported for operating the plant in which the tariff structure, number of operating hours and the ambient temperature are parameters. The capital recovery factor is calculated for 10% interest rate and payback period of 10 years. Full and partial load storage scenarios are considered. The results showed that with the current fixed electricity rate (0.07 $/kWh), there is no gain in introducing ice storage systems for both storage schemes. Combining energy storage and an incentive time structured rate showed reasonable daily bill savings. For base tariff of 0.07 $/kWh during daytime operation and 0.016 $/kWh for off-peak period, savings were achieved for full load storage scenario. Different tariff structure is discussed and the break-even nighttime rate was determined (varies between 0.008 and 0.03 $/kWh). Partial load storage scenario showed to be unattractive where the savings for the base structured tariff was insignificant. (author)
Geothermally Coupled Well-Based Compressed Air Energy Storage

Energy Technology Data Exchange (ETDEWEB)

Davidson, C L [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bearden, Mark D [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Horner, Jacob A [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Appriou, Delphine [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McGrail, B Peter [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-12-01

Previous work by McGrail et al. (2013, 2015) has evaluated the possibility of pairing compressed air energy storage with geothermal resources in lieu of a fossil-fired power generation component, and suggests that such applications may be cost competitive where geology is favorable to siting both the geothermal and CAES components of such a system. Those studies also note that the collocation of subsurface resources that meet both sets of requirements are difficult to find in areas that also offer infrastructure and near- to mid-term market demand for energy storage. This study examines a novel application for the compressed air storage portion of the project by evaluating the potential to store compressed air in disused wells by amending well casings to serve as subsurface pressure vessels. Because the wells themselves would function in lieu of a geologic storage reservoir for the CAES element of the project, siting could focus on locations with suitable geothermal resources, as long as there was also existing wellfield infrastructure that could be repurposed for air storage. Existing wellfields abound in the United States, and with current low energy prices, many recently productive fields are now shut in. Should energy prices remain stagnant, these idle fields will be prime candidates for decommissioning unless they can be transitioned to other uses, such as redevelopment for energy storage. In addition to the nation’s ubiquitous oil and gas fields, geothermal fields, because of their phased production lifetimes, also may offer many abandoned wellbores that could be used for other purposes, often near currently productive geothermal resources. These existing fields offer an opportunity to decrease exploration and development uncertainty by leveraging data developed during prior field characterization, drilling, and production. They may also offer lower-cost deployment options for hybrid geothermal systems via redevelopment of existing well-field infrastructure
Geothermally Coupled Well-Based Compressed Air Energy Storage

Energy Technology Data Exchange (ETDEWEB)

Davidson, Casie L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bearden, Mark D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Horner, Jacob A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cabe, James E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Appriou, Delphine [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McGrail, B. Peter [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-12-20

Previous work by McGrail et al. (2013, 2015) has evaluated the possibility of pairing compressed air energy storage with geothermal resources in lieu of a fossil-fired power generation component, and suggests that such applications may be cost competitive where geology is favorable to siting both the geothermal and CAES components of such a system. Those studies also note that the collocation of subsurface resources that meet both sets of requirements are difficult to find in areas that also offer infrastructure and near- to mid-term market demand for energy storage. This study examines a novel application for the compressed air storage portion of the project by evaluating the potential to store compressed air in disused wells by amending well casings to serve as subsurface pressure vessels. Because the wells themselves would function in lieu of a geologic storage reservoir for the CAES element of the project, siting could focus on locations with suitable geothermal resources, as long as there was also existing wellfield infrastructure that could be repurposed for air storage. Existing wellfields abound in the United States, and with current low energy prices, many recently productive fields are now shut in. Should energy prices remain stagnant, these idle fields will be prime candidates for decommissioning unless they can be transitioned to other uses, such as redevelopment for energy storage. In addition to the nation’s ubiquitous oil and gas fields, geothermal fields, because of their phased production lifetimes, also may offer many abandoned wellbores that could be used for other purposes, often near currently productive geothermal resources. These existing fields offer an opportunity to decrease exploration and development uncertainty by leveraging data developed during prior field characterization, drilling, and production. They may also offer lower-cost deployment options for hybrid geothermal systems via redevelopment of existing well-field infrastructure
Calorimetric investigation on mechanically activated storage energy mechanism of sphalerite and pyrite

International Nuclear Information System (INIS)

Xiao Zhongliang; Chen Qiyuan; Yin Zhoulan; Hu Huiping; Wu Daoxin

2005-01-01

The structural changes of mechanically activated sphalerite and pyrite under different grinding conditions were determined by X-ray powder diffraction (XRD), laser particle size analyzer and elemental analysis. The storage energy of mechanically activated sphalerite and pyrite was measured by a calorimetric method. A thermochemical cycle was designed so that mechanically activated and non-activated minerals reached the same final state when dissolved in the same oxidizing solvent. The results show that the storage energy of mechanically activated sphalerite and pyrite rises with increased in grinding time, and reaches a maximum after a certain grinding period. The storage energy of mechanically activated pyrite decreases when heated under inert atmosphere. The storage energy of mechanically activated sphalerite and pyrite remains constant when treated below 573 K under inert atmosphere. The percentage of the storage energy caused by surface area increase during mechanical activation decreases with increasing grinding time. These results support our opinion that the mechanically activated storage energy of sphalerite is closely related to lattice distortions, and the mechanically activated storage energy of pyrite is mainly caused by the formation of reactive sites on the surface
Energy storage. A varying potential with respect to the envisaged case

International Nuclear Information System (INIS)

Signoret, Stephane

2013-01-01

This article comments the content of a report on the potential of energy storage which indicates that we'll take benefit of some services brought by energy storage by 2030. This study was based on three scenarios regarding the energy mix (the RTE' Median and New scenarios, and the ADEME's scenario) which assign from 36 to 56 per cent to renewable energies in the installed power. The study discussed the impact of the share of intermittent energy on the French grid adaptation in terms of flexibility. It also studied different situations to take geographical situations and constraints into account. These situations are studied with respect to storage problematic (peak consumption smoothing, peak production, and so on). The economic benefit of storage is assessed for these different situations
The rise of organic electrode materials for energy storage.

Science.gov (United States)

Schon, Tyler B; McAllister, Bryony T; Li, Peng-Fei; Seferos, Dwight S

2016-11-07

Organic electrode materials are very attractive for electrochemical energy storage devices because they can be flexible, lightweight, low cost, benign to the environment, and used in a variety of device architectures. They are not mere alternatives to more traditional energy storage materials, rather, they have the potential to lead to disruptive technologies. Although organic electrode materials for energy storage have progressed in recent years, there are still significant challenges to overcome before reaching large-scale commercialization. This review provides an overview of energy storage systems as a whole, the metrics that are used to quantify the performance of electrodes, recent strategies that have been investigated to overcome the challenges associated with organic electrode materials, and the use of computational chemistry to design and study new materials and their properties. Design strategies are examined to overcome issues with capacity/capacitance, device voltage, rate capability, and cycling stability in order to guide future work in the area. The use of low cost materials is highlighted as a direction towards commercial realization.
Biotechnological storage and utilization of entrapped solar energy.

Science.gov (United States)

Bhattacharya, Sumana; Schiavone, Marc; Nayak, Amiya; Bhattacharya, Sanjoy K

2005-03-01

Our laboratory has recently developed a device employing immobilized F0F1 adenosine triphosphatase (ATPase) that allows synthesis of adenosine triphosphate (ATP) from adenosine 5'-diphosphate and inorganic phosphate using solar energy. We present estimates of total solar energy received by Earth's land area and demonstrate that its efficient capture may allow conversion of solar energy and storage into bonds of biochemicals using devices harboring either immobilized ATPase or NADH dehydrogenase. Capture and storage of solar energy into biochemicals may also enable fixation of CO2 emanating from polluting units. The cofactors ATP and NADH synthesized using solar energy could be used for regeneration of acceptor D-ribulose-1,5-bisphosphate from 3-phosphoglycerate formed during CO2 fixation.
Data Storage for Social Networks A Socially Aware Approach

CERN Document Server

Tran, Duc A

2012-01-01

Evidenced by the success of Facebook, Twitter, and LinkedIn, online social networks (OSNs) have become ubiquitous, offering novel ways for people to access information and communicate with each other. As the increasing popularity of social networking is undeniable, scalability is an important issue for any OSN that wants to serve a large number of users. Storing user data for the entire network on a single server can quickly lead to a bottleneck, and, consequently, more servers are needed to expand storage capacity and lower data request traffic per server. Adding more servers is just one step
Prospective study related to the evolution of energy distribution networks. Needs of evolution of technical and organisational models of energy distribution networks with respect to energy transition scenarios in the Provence-Alpes-Cote d'Azur region. Part 1 - Hypotheses and perspectives, Part 2 - Needs of network evolution. Study related to the impact of the electric vehicle and of photovoltaic production on electric distribution networks - Case study for Provence-Alpes-Cote d'Azur

International Nuclear Information System (INIS)

Dauphin, Francois; Fontaine, Frederick

2013-02-01

The first part of this document aims at presenting perspectives of emergence of new energy production, consumption and storage sources, and their impacts on energy (electricity, gas, heat) distribution and transport networks. It is based on two scenarios: the regional climate-air-energy scheme, and the regional Negawatt scenario. The objective was to select a limited number of aspects: solutions enabling an optimal injection of biogas produced in the concerned region, development of photovoltaic energy and electric vehicles and their impact on the balance of medium-voltage and low-voltage networks, and smart grid technologies and their possible impact on the optimisation of electric network management. The second part reports the detailed study of these issues. It more particularly addresses technical impacts of different sectors on electric and gas networks in Provence-Alpes-Cote d'Azur, technical, economic and organisational assets of smart grid technologies, investments policies and implementation planning, and resulting evolutions for energy markets. Related documents published by ERDF and GrDF are provided
Two-stage energy storage equalization system for lithium-ion battery pack

Science.gov (United States)

Chen, W.; Yang, Z. X.; Dong, G. Q.; Li, Y. B.; He, Q. Y.

2017-11-01

How to raise the efficiency of energy storage and maximize storage capacity is a core problem in current energy storage management. For that, two-stage energy storage equalization system which contains two-stage equalization topology and control strategy based on a symmetric multi-winding transformer and DC-DC (direct current-direct current) converter is proposed with bidirectional active equalization theory, in order to realize the objectives of consistent lithium-ion battery packs voltages and cells voltages inside packs by using a method of the Range. Modeling analysis demonstrates that the voltage dispersion of lithium-ion battery packs and cells inside packs can be kept within 2 percent during charging and discharging. Equalization time was 0.5 ms, which shortened equalization time of 33.3 percent compared with DC-DC converter. Therefore, the proposed two-stage lithium-ion battery equalization system can achieve maximum storage capacity between lithium-ion battery packs and cells inside packs, meanwhile efficiency of energy storage is significantly improved.
Toward flexible polymer and paper-based energy storage devices

Energy Technology Data Exchange (ETDEWEB)

Nyholm, Leif [Department of Materials Chemistry, The Aangstroem Laboratory, Uppsala University, Box 538, SE-751 21 Uppsala (Sweden); Nystroem, Gustav; Mihranyan, Albert; Stroemme, Maria [Nanotechnology and Functional Materials, Department of Engineering Sciences, The Aangstroem Laboratory, Uppsala University, Box 534, SE-751 21 Uppsala (Sweden)

2011-09-01

All-polymer and paper-based energy storage devices have significant inherent advantages in comparison with many currently employed batteries and supercapacitors regarding environmental friendliness, flexibility, cost and versatility. The research within this field is currently undergoing an exciting development as new polymers, composites and paper-based devices are being developed. In this report, we review recent progress concerning the development of flexible energy storage devices based on electronically conducting polymers and cellulose containing composites with particular emphasis on paper-based batteries and supercapacitors. We discuss recent progress in the development of the most commonly used electronically conducting polymers used in flexible device prototypes, the advantages and disadvantages of this type of energy storage devices, as well as the two main approaches used in the manufacturing of paper-based charge storage devices. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Research opportunities in salt hydrates for thermal energy storage

Science.gov (United States)

Braunstein, J.

1983-11-01

The state of the art of salt hydrates as phase change materials for low temperature thermal energy storage is reviewed. Phase equilibria, nucleation behavior and melting kinetics of the commonly used hydrate are summarized. The development of efficient, reliable inexpensive systems based on phase change materials, especially salt hydrates for the storage (and retrieval) of thermal energy for residential heating is outlined. The use of phase change material thermal energy storage systems is not yet widespread. Additional basic research is needed in the areas of crystallization and melting kinetics, prediction of phase behavior in ternary systems, thermal diffusion in salt hydrate systems, and in the physical properties pertinent to nonequilibrium and equilibrium transformations in these systems.
Nanowire modified carbon fibers for enhanced electrical energy storage

Science.gov (United States)

Shuvo, Mohammad Arif Ishtiaque; (Bill) Tseng, Tzu-Liang; Ashiqur Rahaman Khan, Md.; Karim, Hasanul; Morton, Philip; Delfin, Diego; Lin, Yirong

2013-09-01

The study of electrochemical super-capacitors has become one of the most attractive topics in both academia and industry as energy storage devices because of their high power density, long life cycles, and high charge/discharge efficiency. Recently, there has been 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 structures combining energy storage and load bearing functionalities, leading to material systems with reduced volume and/or weight. 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 thus fast ion diffusion rates. Scanning Electron Microscopy and X-Ray Diffraction measurements are used for the initial characterization of this nanowire/carbon fiber hybrid material system. Electrochemical testing is performed using a potentio-galvanostat. The results show that gold sputtered nanowire carbon fiber hybrid provides 65.9% higher energy density than bare carbon fiber cloth as super-capacitor.
New energy technologies part 2, storage and low emission technologies

International Nuclear Information System (INIS)

Sabonnadiere, J.C.

2007-01-01

After a first volume devoted to renewable energy sources, this second volume follows the first one and starts with a detailed presentation of energy storage means and technologies. This first chapter is followed by a prospective presentation of innovative concepts in the domain of nuclear energy. A detailed analysis of cogeneration systems, which aim at optimizing the efficiency of heat generation facilities by the adjunction of a power generation unit, allows to outline the advantages and limitations of this process. The next two chapters deal with the development of hydrogen industry as energy vector and with its application to power generation using fuel cells in several domains of use. Content: - forewords: electric power, the new paradigm, the decentralized generation, the energy conversion means; - chapter 1: energy storage, applications in relation with the electricity vector (energy density, storage problems, storage systems); - chapter 2: nuclear fission today and tomorrow, from rebirth to technological jump (2006 energy green book, keeping all energy options opened); nuclear energy in the world: 50 years of industrial experience; main actors: common needs, international vision and strategic instruments; at the eve of a technological jump: research challenges and governmental initiatives; generation 2 (today): safety of supplies and respect of the environment; generation 3 (2010): rebirth with continuous improvements; generation 4 (2040): technological jump to satisfy new needs; education and training: general goals; conclusion: nuclear power as part of the solution for a sustainable energy mix; - chapter 3: cogeneration (estimation of cogeneration potential, environmental impact, conclusions and perspectives); - chapter 4: hydrogen as energy vector (context, energy vector of the future, hydrogen generation, transport, distribution and storage; applications of hydrogen-energy, risks, standards, regulations and acceptability; hydrogen economics; hydrogen
Graphene-Based Systems for Enhanced Energy Storage

Directory of Open Access Journals (Sweden)

Amplianitis Aris

2017-01-01

Full Text Available Extensive global research efforts have focused on the exploitation of graphene for enhanced energy storage. Novel graphene-based composite material electrodes have been developed, in many cases with reports of outstanding performance. However, the development of these composites involve extremely complex and costly procedures/methods whose scalability and eventual commercial exploitation is extremely hard [1]. Within the present activity the use of graphene nanotechnology is exploited to manufacture electrodes for supercapacitors. The goal however is to achieve electrodes with increased specific energy density (compared to the currently commercially available products using proven and simple manufacturing procedures that can easily be scaled-up and offer competitive products. The roadmap was developed under the framework of European Space Agency highlighting the main advantages brought up from this technology. The activity is separated in three parallel routes; the development and test planning of small–scale production of graphene based materials via the tape casting technology, the establishment of a reliable and low cost industrial production process (scale-up for these materials and the development and testing of an energy storage demonstrator that shall incorporate the novel electrodes and exhibit their favorable characteristics in energy storage applications for use in space.
Thermodynamic characteristics of a novel supercritical compressed air energy storage system

International Nuclear Information System (INIS)

Guo, Huan; Xu, Yujie; Chen, Haisheng; Zhou, Xuezhi

2016-01-01

Highlights: • A novel supercritical compressed air energy storage system is proposed. • The energy density of SC-CAES is approximately 18 times larger than that of conventional CAES. • The characteristic of thermodynamics and exergy destruction is comprehensively analysed. • The corresponding optimum relationship between charging and discharging pressure is illustrated. • A turning point of efficiency is indicated because of the heat transfer of crossing the critical point. - Abstract: A novel supercritical compressed air energy storage (SC-CAES) system is proposed by our team to solve the problems of conventional CAES. The system eliminates the dependence on fossil fuel and large gas-storage cavern, as well as possesses the advantages of high efficiency by employing the special properties of supercritical air, which is significant for the development of electrical energy storage. The thermodynamic model of the SC-CAES system is built, and the thermodynamic characters are revealed. Through the exergy analysis of the system, the processes of the larger exergy destruction include compression, expansion, cold storage/heat exchange and throttle. Furthermore, sensitivity analysis shows that there is an optimal energy releasing pressure to make the system achieve the highest efficiency when energy storage pressure is constant. The efficiency of SC-CAES is expected to reach about 67.41% when energy storage pressure and energy releasing pressure are 120 bar and 95.01 bar, respectively. At the same time, the energy density is 18 times larger than that of conventional CAES. Sensitivity analysis also shows the change laws of system efficiency varying with other basic system parameters. The study provides support for the design and engineering of SC-CAES.
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......, even less economically viable. Although there are a number of storage technologies, as chemical, potential or heat energy, not all those technologies are optimal for each energy system. The paper shows results of energy planning and several cases where use of smart energy storage system could help......Primary energy import dependence of the European Union is currently around 53%, and it is expected that in the next 20-30 years it will reach or surpass 70%. The situation in Croatia is similar. In 2007 import dependence was 53.1%, while for 2030 it is predicted to reach 72%. Such import dependence...

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