A novel multicriteria sustainability investigation of energy storage systems

Affordable, clean, efficient, flexible, and reliable energy storage is an important component of sustainable energy systems. There are several studies in the literature concentrating on improving the sustainability performance of energy storage systems from economic and technical perspectives. However, a comprehensive performance investigation of energy storage systems that take economic, environmental, social, and technical criteria into account is still needed. For that reason, in the present study, it is aimed to perform a complete assessment and analysis of the sustainability of energy storage systems for residential applications in communities and cities. Pumped hydro, conventional batteries, high‐temperature batteries, flow batteries, and hydrogen are the selected energy storage systems. In order to handle the vagueness and ambiguity during the assessment and to eliminate the perceived hesitancy in the decision makers' preferences, an innovative method, a hybrid hesitant fuzzy multicriteria decision‐making (MCDM) methodology composed of hesitant fuzzy analytic hierarchy process (HFAHP) and hesitant fuzzy technique for order preference by similarity to ideal solution (HFTOPSIS), is utilized to assess the sustainability of the selected systems. In this study, four different performance criteria: economic (power cost and energy cost), environmental (pollutant emissions, area requirement, wastewater quality, and solid waste production), social (safety, accessibility, ease of use, and public acceptance), and technical (efficiency, storage capacity, cycling limit, and performance degradation) are taken into consideration. The performance evaluation results indicate that technical performance has the highest influence and social performance has the lowest influence when evaluating the sustainability of the selected energy storage systems. And hydrogen has the highest sustainability performance compared with the other selected energy storage options.     

Analysis of economic benefits and risks of energy storage project under financial leasing model

储能项目的经济性是制约储能项目商业化的重要因素之一。其中商业模式对项目经济性起着决定性作用。通过分析国内储能系统相关政策与发展现状,根据给定的储能项目系统结构与盈利方式,建立项目经济模型,通过内部收益率、投资回收期和发展成本等经济性指标评价了项目的经济性。进一步,以储能项目商业化融资难的问题为突破点,引入直接融资租赁模式,评估了在融资租赁公司低成本采购优势下项目的经济性。通过分析可知,融资租赁模式的引入可以缓解企业前几年的资金压力,提高项目的经济效益。     

Five Solar-Energy Desalination Systems

This paper gives an overview of the Solar Energy Storage Program at the Solar Energy Research Institute. The program provides research, systems analyses, and economic assessments of thermal and thermochemical energy storage and transport. Current activities include experimental research into very high temperature (above 800^°C) thermal energy storage and assessment of novel thermochemical energy storage and transport systems.

The applications for such high-temperature storage are thermochemical processes, solar thermal-electric power generation, regeneration of heat and electricity, industrial process heat, and thermally regenerative electrochemical systems.

The research results for five high-temperatuTe thermal energy storage technologies and two thermochemical systems are described.     

Bulk energy storage potential in the USA, current developments and future prospects

Stored energy can provide electricity during periods of high demand, as currently demonstrated with bulk storage systems such as pumped hydro storage (PHS), which accounts for only 2.5% of the current installed base load in the USA. Sites for future developments have become less available, and environmental siting issues, as well as high costs have stopped further prospects. This paper looks at the potential beyond PHS, with bulk storage systems such as compressed air energy storage (CAES) flow-batteries and 1 MW flywheel systems that can provide system stability/support at the grid, substations and distributed level. Current developments in bulk energy storage will be reviewed as well as some storage project developments incorporating wind energy and the impact on base-loaded coal and natural gas fired GT combined cycle plants. The large potential and the economic benefits for energy storage in the US will be examined.     

Review on combined wind power generation and energy storage systems

储能系统由于能够实现电能的时空平移,具有响应速度快,规模化等优点,是改善风电波动性,提高其并网能力的有效手段,构建风储联合发电系统成为目前研究重点.简单介绍了风电并网对电力系统的影响及不同类型电池储能技术的发展现状,给出了部分国内外风储联合发电系统的示范工程,并分析了平滑风电功率波动,跟踪计划出力曲线和削峰填谷3种主要运行方式,重点阐述了目前风储联合发电系统控制策略和储能容量配置研究现状,对进一步开展风储联合发电系统的研究进行了展望,指出经济性仍然是制约储能技术应用的关键问题之一,提高包含储能单元的风储联合发电系统的经济性是今后的研究重点.     

新能源系统中双储能耦合燃煤机组的应用策略研究

  目的  随着新能源电力消费比例不断提高,燃煤机组耦合双储能技术的能源系统发展受到广泛关注。  方法  文章基于能源系统组成、储能技术特性、项目示范情况以及技术瓶颈等方面的分析,针对风电、光伏嵌入下双储能技术耦合燃煤机组参与电力系统调峰应用开展了运行控制策略研究。  结果  双储能技术耦合燃煤机组可通过不同的结构组成、运行策略优化有效解决新能源系统运行稳定性、能源高效利用以及技术经济性等问题,但目前尚未到实现大规模商业化应用阶段。  结论  双储能耦合燃煤机组在新能源系统中的推广应用,需要对双储能技术的策略优化及储能技术本身的发展突破方面不断开展工作。     

Review of hydrogen technologies based microgrid: Energy management systems,challenges and future recommendations

With the significant development of renewable energy sources in recent years, integrating energy storage systems within a renewable energy microgrid is getting more attention as a promising future hybrid energy system configuration. Recently, hydrogen systems are being considered a promising energy storage option that utilised electrolysers to produce and store hydrogen when energy is surplus and re-supply it into microgrids using fuel cells in energy shortage scenarios. To control the energy flow within such hybrid energy systems, designing an energy management system should be considered a critical task, that allows the technical and economic optimal operation of microgrids. This study presents a comprehensive review and analysis of different energy management systems for hydrogen technologies-based microgrids, including the strategies’ objectives, constraints and techniques as well as the optimisation methods and simulation tools. In addition, an insightful discussion of the existing challenges and suggestions for the future research direction has been given.     

Economic prospects for the application of new electric energy storage devices

The technical and economic properties of new storage devices for electric energy such as batteries, hydrogen storage systems, flywheels, steam storage plants and compressed air storage facilities are compared with conventional peak power plants such as gas turbines and hydroelectric storage systems. The analysis shows that batteries, steam storage plants and compressed air storage facilities may be economically competitive with conventional peak power devices. Batteries are especially appropriate for dispersed energy storage systems.Utilization of storage devices instead of gas turbines results in substitution of oil or natural gas by coal or nuclear fuel.     

Dynamic modelling and multi-objective optimization of off-grid hybrid energy systems by using battery or hydrogen storage for different climates

The energy storage problem is an essential issue in renewable energy-based power systems. A comprehensive study is performed to evaluate off-grid hybrid renewable energy systems with a battery bank or a hydrogen system employed as the energy storage option. Dynamic modelling is proposed to see daily and seasonally changes in the system. The economic feasibility of the system and its environmental impacts are investigated in three locations. A multi-objective optimization method based on the Taguchi approach is employed to minimize both levelized cost of energy and the CO₂ emissions. Various weight factors were assigned to understand the response of different optimization targets. The results highlight that the hybridization of energy resources allows the annual emissions to be cut by 68–78% for battery storage, 84–90% for hydrogen storage, compared to a diesel-only system. Despite having higher costs, the systems with hydrogen storage can store energy in the long term; therefore, they have lower CO₂ emissions.     

Economical assessment of a wind–hydrogen energy system using WindHyGen software

This paper considers the problem of analyzing the economical feasibility of a wind–hydrogen energy storage and transformation system. Energy systems based on certain renewable sources as wind power, have the drawback of random input making them a non-reliable supplier of energy. Regulation of output energy requires the introduction of new equipment with the capacity to store it. We have chosen the hydrogen as an energy storage system due to its versatility. The advantage of these energy storage systems is that the energy can be used (sold) when the demand for energy rises, and needs (prices) therefore are higher. There are two disadvantages: (a) the cost of the new equipment and (b) energy loss due to inefficiencies in the transformation processes. In this research we develop a simulation model to aid in the economic assessment of this type of energy systems, which also integrates an optimization phase to simulate optimal management policies. Finally we analyze a wind–hydrogen farm in order to determine its economical viability compared to current wind farms.     

Comparing electricity,heat and biogas storages’ impacts on renewable energy integration

Increasing penetration 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 utilising 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 article takes its point of departure in an all-inclusive 100% renewable energy scenario developed for the Danish city Aalborg based on wind power, bio-resources and low-temperature geothermal heat. The article investigates the system impact of different types of energy storage systems including district heating storage, biogas storage and electricity storage. The system is modelled in the energy systems analyses model energyPRO with a view to investigating how the different storages marginally affect the amount of wind power that may be integrated applying the different storage options and the associated economic costs. Results show the largest system impact but also most costly potential are in the form of electricity storages.     

Cost optimization of the design of CHCP (combined heat,cooling and power) systems under legal constraints

Combined heat, cooling and power (CHCP) systems are interesting for the supply of different energy services in urban districts and in large buildings. CHCP systems utilize a fuel's energy to a greater extent, because the cogenerated heat can be used for heating in winter as well as for cooling in summer with an absorption refrigerator. The use of thermal energy storage (TES) provides the additional advantage of covering variable thermal demands while the production system operates continuously at nominal conditions. Thus, energy supply systems integrating the technologies of cogeneration, absorption refrigeration and thermal storage can provide substantial benefits from economic, energetic and environmental viewpoints. In this paper an optimization model is developed, using mixed integer linear programming (MILP), to determine the preliminary design of CHCP systems with thermal storage. The objective function to be minimized is the total annual cost. Taking into account the legal constraints imposed on cogeneration systems in Spain, the optimization model is applied to design a system providing energy services for a set of buildings constituted of 5000 apartments located in the city of Zaragoza (Spain). The effect of legal constraints in the design and operation of CHCP systems is highlighted in this study.     

考虑广义储能的综合能源系统典型日优化运行

由电、热、冷能系统之间的耦合与互联构成的综合能源系统(IES),对于构建环保、高效、经济的能源系统至关重要。着眼于IES运行环节,考虑广义储能设备的投入运行,并计及IES内各设备出力约束,以调度周期内运行费用最低为目标函数,采用基于yalmip平台的cplex优化算法包对IES优化运行进行求解。该方法考虑了分时电价和典型日负荷特性对IES运行的影响,并与不计广义储能的运行模式进行对比分析。算例仿真表明,投入广义储能设备不仅更有利于IES的经济效益,而且有利于IES安全稳定运行。     

Hydrogen energy storage systems to improve wind power plant efficiency considering electricity tariff dynamics

One of the limitations of the efficiency of renewable energy sources is the stochastic nature of generation; consequently, it is necessary to use high-capacity energy storage systems such as hydrogen storage for its integration into existing power networks. At the same time, electricity market tariffs for large enterprises change during the day. Therefore, it can be assumed that storing energy during cheaper hours and usage in more expensive hours allows increasing the efficiency of renewable energy sources. Evaluation of the economic efficiency of an energy storage system requires simulation with a step of at least 1 h for several years since the use of averaged production volume and averaged electricity tariffs will not allow obtaining an adequate to the task accuracy. A simulation model and software have been implemented to perform simulations and calculate the economic efficiency of a wind turbine with and without a hydrogen storage device. The methodology has been approved on three-year real data of wind speeds and electricity tariffs in the Novosibirsk region and Krasnodar Territory (Russian Federation).     

Lifetime and economic analyses of lithium‐ion batteries for balancing wind power forecast error

Wind power plant operators are often faced with extra charges when their power production does not match the forecasted power. Because the accuracy of wind power forecasts is limited, the use of energy storage systems is an attractive alternative even when large‐scale aggregation of wind power is considered. In this paper, the economic feasibility of lithium‐ion batteries for balancing the wind power forecast error is analysed. In order to perform a reliable assessment, an ageing model of lithium‐ion battery was developed considering both cycling and calendar life. The economic analysis considers two different energy management strategies for the storage systems and it is performed for the Danish market. Analyses have shown that the price of the Li‐ion BESS needs to decrease by 6.7 times in order to obtain a positive net present value considering the present prices on the Danish energy market. Moreover, it was found that for total elimination of the wind power forecast error, it is required to have a 25‐MWh Li‐ion battery energy storage system for the considered 2 MW WT. Copyright © 2015 John Wiley & Sons, Ltd.     

Hybridized off-grid fuel cell/wind/solar PV /battery for energy generation in a small household: A multi-criteria perspective

In this paper, the robust capability of HOMER and Criteria-COPRAS is deployed to explore the prospect of selecting a renewable energy system. The energy system consisting of wind turbines, solar photovoltaic (PV), fuel cell (FC), electrolyzer, hydrogen storage, and battery energy storage is intended to power a residential load in Lagos Nigeria. Based on the economic metric, the results show that the optimal system is a PV-Battery whose total net present cost (TNPC) and initial investment cost are $9060 and $3,818, respectively. However, if the energy systems are ranked based on multiple criteria (economic, technical and environmental aspects), the most preferred of the feasible energy systems is a hybrid PV-FC-wind-battery (TNPC-$10,324, initial cost: $7670). The study results indicate that, for viability in the adoption of hydrogen energy storage as part of the hybrid energy system, the selection metric should be based on more than one criterion.     

The utility of energy storage to improve the economics of wind–diesel power plants in Canada

Wind energy systems have been considered for Canada's remote communities in order to reduce their costs and dependence on diesel fuel to generate electricity. Given the high capital costs, low-penetration wind–diesel systems have been typically found not to be economic. High-penetration wind–diesel systems have the benefit of increased economies of scale, and displacing significant amounts of diesel fuel, but have the disadvantage of not being able to capture all of the electricity that is generated when the wind turbines operate at rated capacity.Two representative models of typical remote Canadian communities were created using HOMER, an NREL micro-power simulator to model how a generic energy storage system could help improve the economics of a high-penetration wind–diesel system. Key variables that affect the optimum system are average annual wind speed, cost of diesel fuel, installed cost of storage and a storage systems overall efficiency. At an avoided cost of diesel fuel of 0.30 $Cdn/kWh and current installed costs, wind generators are suitable in remote Canadian communities only when an average annual wind speed of at least 6.0 m/s is present. Wind energy storage systems become viable to consider when average annual wind speeds approach 7.0 m/s, if the installed cost of the storage system is less than 1000 $Cdn/kW and it is capable of achieving at least a 75% overall energy conversion efficiency. In such cases, energy storage system can enable an additional 50% of electricity from wind turbines to be delivered.     

Evaluating energy storage technologies for wind power integration

In this paper we perform a cost analysis of different types of energy storage technologies. We evaluate eleven storage technologies, including lead-acid, sodium–sulfur, nickel–cadmium, and lithium-ion batteries, superconducting magnetic energy storage, electrochemical capacitors, flywheels, flow batteries, pumped hydro and compressed air energy storage systems. We perform economic analysis for key applications associated with a wind farm integrated into the electric grid, including load shifting, frequency support, and power quality. We identify the key characteristics that affect the economic viability for these technologies, perform sensitivity analyses based on key performance criteria and find improvement areas that could make them more competitive in the near future.     

电池储能电站电网侧经济效益及运行效益分析

  目的  电池储能电站的建设是未来电网发展的必然趋势,文章旨在研究当前电池技术和峰谷电差政策条件下的电池储能电站的经济效益和运行效益。  方法  以电网侧储能电站为对象出发,分析以经济效益指数为判据的经济效益、以延缓变电站扩容建设为衡量的运行效益。同时,以东莞地区电池储能电站为例,对其直接经济效益、运行效益和其他效益进行分析。  结果  在当前电池技术和峰谷电差政策的状况下,东莞电池储能电站的经济效益总体略有亏损,但考虑到建设储能电站存在的其他方面的运行效益等,发展电池储能电站有小幅盈利。  结论  以东莞地区电池储能电站为例的经济效益及运行效益分析也可以为其他同类型电池储能电站的效益分析提供参考。     

Front Cover

The economic benefits of energy storage and their impact on electric power brokering are examined. Estimated costs for energy storage technologies are given and discussed. One way to integrate storage technologies into utility systems to exploit their potential, i.e. by letting a storage plant serve as the hub of a utility, is explored. Ways to minimize financial risk are considered.<>