A review of electrical energy storage technologies for renewable power generation and smart grids

储能技术是突破可再生能源大规模开发利用瓶颈的关键技术,是智能电网的必要组成部分.在储能市场商业化雏形阶段,系统性的比较分析各类储能技术的性能特点,为未来市场发展提供筛选技术路线的框架基础至关重要.本文阐述了储能技术在可再生能源发电和智能电网中的作用,对物理储能(抽水蓄能,压缩空气储能,飞轮储能),电化学储能(二次电池,液流电池),其它化学储能(氢能,合成天然气)等储能技术进行了系统的比较与分析,最后提出储能技术的发展趋势.     

储能技术发展概况研究

我国能源建设面临的主要问题有人均能源储备量少,能源开发利用设备和技术落后,环境污染严重等。因此,研究价值高、应用前景广阔的储能技术,已受到科技界和企业界的密切关注,成为国际能源界研究的热点之一。储能方式主要有物理储能、化学储能、电磁储能和相变储能四大类型,其中物理储能包括抽水蓄能、压缩空气储能、飞轮储能及高温熔岩等;化学储能包括铅酸、锂离子、钠硫和液流等电池储能;电磁储能包括超级电容储能、超导储能和超级电池;相变储能包括蓄热和蓄冷储能等。对储能技术进行分类介绍,对其工作原理、技术现状、发展前景及优缺点进行了讨论,为进一步研究储能技术提供参考。     

Comprehensive study of the performance of alkaline organic redox flow batteries as large‐scale energy storage systems

Alkaline‐based organic redox flow batteries (AORFBs) attract significant interest because they can retain the advantages of vanadium redox flow batteries (VRFBs) while being low‐cost because expensive vanadium is replaced with easily synthesizable metal‐free organic compounds and earth‐abundant raw materials. A comprehensive experimental study on the performance of AORFBs using alloxazine 7/8‐carboxylic acid (ACA) and ferrocyanide was conducted to investigate the feasibility of these batteries as large‐scale energy storage systems. The operating conditions, such as the electrolyte concentration, flowrate, and temperature, were varied in this study. The results show that the present AORFB achieves an energy efficiency above 76% at 80 mA cm^?2 at elevated temperature (55°C). Compared with those of VRFBs, AORFBs exhibit very good thermal stability and capacity retention. A large‐scale AORFB was constructed and tested to confirm the effectiveness of AORFBs.     

A review on theory and application of chemical heat pump in thermal energy storage

化学热泵是高效,环保的新型能源技术,在余热回收,储热,可再生能源等领域具有广泛的应用前景.本文综述了化学热泵系统的一般理论和在储热技术中的应用,介绍了化学热泵系统技术在反应与工质对选择,传热强化以及工业研究与应用等方面的发展.     

The micro‐/nano‐PCMs for thermal energy storage systems: A state of art review

With advancement in technology—nanotechnology, various thermal energy storage (TES) materials have been invented and modified with promising thermal transport properties. Solid‐liquid phase change materials (PCMs) have been extensively used as TES materials for various energy applications due to their highly favourable thermal properties. The class of PCMs, organic phase change materials (OPCMs), has more potential and advantages over inorganic phase change materials (IPCMs), having high phase change enthalpy. However, OPCMs possess low thermal conductivity as well as density and suffer leakage during the melting phase. The encapsulation technologies (ie, micro and nano) of PCMs, with organic and inorganic materials, have a tendency to enhance the thermal conductivity, effective heat transfer, and leakage issues as TES materials. The encapsulation of PCMs involves several technologies to develop at both micro and nano levels, called micro‐encapsulated PCMs (micro‐PCM) and nano‐encapsulated PCMs (nano‐PCM), respectively. This study covers a wide range of preparation methods, thermal and morphological characteristics, stability, applications, and future perspective of micro‐/nano‐PCMs as TES materials. The potential applications, such as solar‐to‐thermal and electrical‐to‐thermal conversions, thermal management, building, textile, foam, medical industry of micro‐ and nano‐PCMs, are reviewed critically. Finally, this review paper highlights the emerging future research paths of micro‐/nano‐PCMs for thermal energy storage.     

A feasibility study of using thermal energy storage in a conventional air‐conditioning system

An Erratum has been published for this article in International Journal of Energy Research 2004; 28 (13): 1213. This paper deals with the simulation of thermal energy storage (TES) system for HVAC applications. TES is considered to be one of the most preferred demand side management technologies for shifting cooling electrical demand from peak daytime hours to off peak night hours. TES is incorporated into the conventional HVAC system to store cooling capacity by chilling ethylene glycol, which is used as a storage medium. The thermodynamic performance is assessed using exergy and energy analyses. The effects of various parameters such as ambient temperature, cooling load, and mass of storage are studied on the performance of the TES. A full storage cycle, with charging, storing and discharging stages, is considered. In addition, energy and exergy analysis of the TES is carried out for system design and optimization. The temperature in the storage is found to be as low as 6.4°C after 1 day of charging without load for a mass of 250 000 kg. It is found that COP of the HVAC system increases with the decrease of storage temperature. Energy efficiency of the TES is found to be 80% for all the mass flow rate of the discharging fluid, whereas exergy efficiency varies from 14 to 0.5%. This is in fact due to the irreversibilities in a TES process destroy a significant amount of the input exergy, and the TES exergy efficiencies therefore become always lower than the corresponding energy efficiencies. Copyright © 2004 John Wiley & Sons, Ltd.     

Overview of international roadmap studies on energy storage technologies

储能技术及其市场前景近年来受到了高度关注,科技和示范工程不断取得新的成果,如何科学规划储能技术的发展是各国决策者面临的重要问题。技术路线图作为一种重要的战略规划工具开始得到储能业界的关注,一些国家和组织已开始尝试运用技术路线图研究储能技术的未来发展路径和前景,本文综述了国际上的相关研究成果,从研究目的、研究方法和核心目标等方面做了归纳,供有关决策机构和业界参考。     

液流电池储能技术研究现状与展望

液流电池技术利用流动的电解液作为电化学储能介质,适合于进行大容量电能与化学能的转化与储存。液流电池通常具有寿命长、效率高等技术特征,在平滑风能、太阳能等可再生能源发电出力以及微型电网、智能电网建设等方面有着广阔的应用前景。本文论述了液流电池的研究与开发现状,概述了目前逐渐具备工程实施能力的全钒液流电池体系,分析了液流电池新体系的研究开发状况,指明了它们各自需要进行技术突破的重要问题,最后展望了金属/ 空气液流电池的技术优势与未来发展前景。     

A review on long-term sorption solar energy storage

In the past decade, long-term sorption and thermochemical heat storage has generated lot of interest. This paper presents the state of the art in this field of research, materials used in these systems and technological difficulties that researchers are set against. An emphasis is put on recent demonstrative projects including absorption and adsorption for long-term solar energy storage. It emerges that considerable breakthrough have been made. Even though there is no mature long-term sorption or thermochemical energy storage yet, primarily due to the high cost of materials, the suitability of this technology to long-term storage remains its main power of attracting.     

Recent progress in thermal energy storage materials

本文结合储热材料的分类、特点、应用及存在的问题对储热材料的最新研究进展进行了综述,主要包括有机相变储热材料、熔融盐类相变储热材料、合金相变储热材料及复合类储热材料。探讨了储热材料成分组成、制备工艺及性能特点,进一步介绍了其最新研究进展,并对储热材料的下一步研究进行了展望,提出开发高性能纳微复合结构储热材料是未来研究的重点。     

Estimation of variability and predictability of large‐scale wind energy in The Netherlands

This paper presents a data‐driven approach for estimating the degree of variability and predictability associated with large‐scale wind energy production for a planned integration in a given geographical area, with an application to The Netherlands. A new method is presented for generating realistic time series of aggregated wind power realizations and forecasts. To this end, simultaneous wind speed time series—both actual and predicted—at planned wind farm locations are needed, but not always available. A 1‐year data set of 10‐min averaged wind speeds measured at several weather stations is used. The measurements are first transformed from sensor height to hub height, then spatially interpolated using multivariate normal theory, and finally averaged over the market resolution time interval. Day‐ahead wind speed forecast time series are created from the atmospheric model HiRLAM (High Resolution Limited Area Model). Actual and forecasted wind speeds are passed through multi‐turbine power curves and summed up to create time series of actual and forecasted wind power. Two insights are derived from the developed data set: the degree of long‐term variability and the degree of predictability when Dutch wind energy production is aggregated at the national or at the market participant level. For a 7.8 GW installed wind power scenario, at the system level, the imbalance energy requirements due to wind variations across 15‐min intervals are ±14% of the total installed capacity, while the imbalance due to forecast errors vary between 53% for down‐ and 56% for up‐regulation. When aggregating at the market participant level, the balancing energy requirements are 2–3% higher. Copyright © 2008 John Wiley & Sons, Ltd.     

A review of marine renewable energy storage

Marine renewable energies are promising enablers of a cleaner energy future. Some technologies, like wind, are maturing and have already achieved commercial success. Similar to their terrestrial counterparts, marine renewable energy systems require energy storage capabilities to achieve the flexibility of the 21st century grid demand. The unique difficulties imposed by a harsh marine environment challenge the unencumbered rise of marine renewable energy generation and storage systems. In this study, the fundamentals of marine renewable energy generation technologies are briefed. A comprehensive review and comparison of state‐of‐the‐art novel marine renewable energy storage technologies, including pumped hydro storage (PHS), compressed air energy storage (CAES), battery energy storage (BES), hydrogen energy storage (HES), gravity energy storage (GES), and buoyancy energy storage (ByES), are conducted. The pros and cons, and potential applications, of various marine renewable energy storage technologies are also compiled. Finally, several future trends of marine renewable energy storage technologies are connoted.     

Energy storage in the UK electrical network: Estimation of the scale and review of technology options

This paper aims to clarify the difference between stores of energy in the form of non-rechargeable stores of energy such as fossil-fuels, and the storage of electricity by devices that are rechargeable. The existing scale of these two distinct types of storage is considered in the UK context, followed by a review of rechargeable technology options. The storage is found to be overwhelmingly contained within the fossil-fuel stores of conventional generators, but their scale is thought to be determined by the risks associated with long supply chains and price variability. The paper also aims to add to the debate regarding the need to have more flexible supply and demand available within the UK electrical network in order to balance the expected increase of wind derived generation. We conclude that the decarbonisation challenge facing the UK electricity sector should be seen not only as a supply and demand challenge but also as a storage challenge.     

Experimental and numerical study on charging processes of an ice‐on‐coil thermal energy storage system

In this study, an external melt ice‐on‐coil thermal storage was studied and tested over various inlet conditions of secondary fluid—glycol solution—flow rate and temperature in charging process. Experiments were conducted to investigate the effect of inlet conditions of secondary fluid and validate the numerical model predictions on ice‐on‐coil thermal energy storage system. The total thermal storage energy and the heat transfer rate in the system were investigated in the range of 10 l min ^?1?V??60 l min ^?1. A new numerical model based on temperature transforming method for phase change material (PCM) described by Faghri was developed to solve the problem of the system consisting of governing equations for the heat transfer fluid, pipe wall and PCM. Numerical simulations were performed to investigate the effect of working conditions of secondary fluid and these were compared with the experimental results. The numerical results verified with experimental investigation show that the stored energy rises with increasing flow rate a decreasing tendency. It is also observed that the inlet temperature of the fluid has more influence on energy storage quantity than flow rate. Copyright © 2006 John Wiley & Sons, Ltd.     

Application of superconducting magnetic energy storage in electrical power and energy systems: a review

Superconducting magnetic energy storage (SMES) is known to be an excellent high‐efficient energy storage device. This article is focussed on various potential applications of the SMES technology in electrical power and energy systems. SMES device founds various applications, such as in microgrids, plug‐in hybrid electrical vehicles, renewable energy sources that include wind energy and photovoltaic systems, low‐voltage direct current power system, medium‐voltage direct current and alternating current power systems, fuel cell technologies and battery energy storage systems. An extensive bibliography is presented on these applications of SMES. Also, some conclusive remarks in terms of future perspective are presented. Also, the present ongoing developments and constructions are also discussed. This study provides a basic guideline to investigate further technological development and new applications of SMES, and thus benefits the readers, researchers, engineers and academicians who deal with the research works in the area of SMES. Copyright © 2017 John Wiley & Sons, Ltd.     

Optimization study of large‐scale low‐grade energy recovery from conventional Rankine cycle power plants

This study evaluates large‐scale low‐grade energy recovery (LS‐LGER) from a conventional coal‐fired Rankine cycle (RC) as a ‘green’ option to offsetting the cost of treating pollution. An energy and exergy analysis of a reference generating station isolates the key areas for investigation into LS‐LGER. This is followed by a second law analysis and a detailed optimization study for a revised RC configuration, which provides a conservative estimate of the possible energy recovery. Cycle optimization based on specific power output, and including compact heat exchanger designs, indicates plant efficiency improvements (with high‐capacity equipment) of approximately 2 percentage points with reduced environmental impact. Copyright © 2009 John Wiley & Sons, Ltd.     

节能的地下含水层蓄热(冷)器

分析了地下含水层蓄热（冷）的特点，阐述了使用含水层蓄热（冷）的系统节能和环保的重要意义，介绍了一些欧洲应用实例。     

Research progress of solar thermochemical energy storage

Solar thermal power generation technology has great significance to alleviate global energy shortage and improve the environment. Solar energy must be stored to provide a continuous supply because of the intermittent and instability nature of solar energy. Thermochemical storage (TCS) is very attractive for high‐temperature heat storage in the solar power generation because of its high energy density and negligible heat loss. To further understand and develop TCS systems, comprehensive analyses and studies are very necessary. The basic principle and main components of a solar TCS system are described in this paper. Besides, recent progress and existing problems of several promising reaction systems are introduced. Further research directions are pointed out considering the technical, economic, and environmental issues that existed in the wide application of TCS. Copyright © 2014 John Wiley & Sons, Ltd.     

Graphene‐based materials for flexible electrochemical energy storage

Sustainable development of renewable energy sources is one of the most important themes that humanity faces in this century. Wide use of renewable energy sources will require a drastically increased ability to store electrical energy. Electrochemical energy storage devices are expected to play a key role. With the increased demand in flexible energy resource for wearable electronic devices, great efforts have been devoted to developing high‐quality flexible electrodes for advanced energy storage and conversion systems. Because of its high specific surface area, good chemical stability, high mechanical flexibility, and outstanding electrical properties, graphene, a special allotrope of carbon with two‐dimensional mono‐layered network of sp² hybridized carbon, have been showing great potential in next‐generation energy conversion and storage devices. This review presents the latest advances on the flexible graphene‐based materials for the most vigorous electrochemical energy storage devices, that is, supercapacitors and lithium‐ion batteries. Copyright © 2014 John Wiley & Sons, Ltd.     

Preparation of pentadecane/poly(melamine‐urea‐formaldehyde) microcapsules for thermal energy storage applications

Phase change materials (PCMs) with suitable melting ranges for thermal energy storage applications are alkanes, paraffins, fatty acids, eutectic mixtures, and inorganic PCMs. Paraffinic hydrocarbons and fatty acids with low solubility in water are usually the preferred candidates. Pentadecane, which is an alkane hydrocarbon with the chemical formula C₁₅H₃₂, was used as PCM in this study. The pentadecane was microencapsulated with a poly(melamine‐urea‐formaldehyde (MUF)) shell for thermal energy storage. Pentadecane/poly(MUF) microcapsules were prepared by in situ polymerization method. The morphological analysis of pentadecane microcapsules was analyzed with scanning electron microscopy (SEM). Thermal properties of microcapsulated pentadecane were determined by differential scanning calorimetry (DSC). The results demonstrated that pentadecane/PUF microcapsules were prepared successfully, and they offer proper phase transition temperature range (8.7°C and 8.1°C) and heat enthalpy values (84.5 and ?88.2 kJ/kg) for thermal energy storage applications. According to the results, it was determined that pentadecane/poly(MUF) microcapsules have good potential for thermal energy storage applications.