Development and technology status of energy storage in depleted gas reservoirs

Utilizing energy storage in depleted oil and gas reservoirs can improve productivity while reducing power costs and is one of the best ways to achieve synergistic development of"Carbon Peak–Carbon Neutral"and"Underground Resource Utiliza-tion".Starting from the development of Compressed Air Energy Storage(CAES)technology,the site selection of CAES in depleted gas and oil reservoirs,the evolution mechanism of reservoir dynamic sealing,and the high-flow CAES and injection technology are summarized.It focuses on analyzing the characteristics,key equipment,reservoir construction,application scenarios and cost analysis of CAES projects,and sorting out the technical key points and existing difficulties.The devel-opment trend of CAES technology is proposed,and the future development path is scrutinized to provide reference for the research of CAES projects in depleted oil and gas reservoirs.

Sizing of Energy Storage Systems for Output Smoothing of Renewable Energy Systems

光伏、风力发电等可再生能源（renewable energysources，RESs）具有随机性、间歇性等特点。为了抑制RESs输出波动对电网的不利影响，提出了用于平滑RESs发电系统功率输出的储能系统（energy storage system，ESS）容量优化确定方法。利用离散傅里叶变换（discrete Fouriertransform，DFT）对RESs输出功率进行频谱分析，基于频谱分析结果，考虑ESS充放电效率、荷电状态（stateofcharge，soc）及RESs发电系统目标功率输出波动率的约束，确定所需ESS最小容量。采用美国华盛顿州实际观测风速数据及日本东北电力公司风电场接入电网20rnin有功功率波动规范（最大波动率为10％），在一风力发电系统中对该方法进行了验证。算例结果表明采用该方法能够以较小的容量将风机输出最大波动率由61．7％降到9．9％。

Jaya Learning-Based Optimization for Optimal Sizing of Stand-Alone Photovoltaic,Wind Turbine,and Battery Systems

Renewable energy sources(RESs)are considered to be reliable and green electric power generation sources.Photovoltaics(PVs)and wind turbines(WTs)are used to provide electricity in remote areas.Optimal sizing of hybrid RESs is a vital challenge in a stand-alone environment.The meta-heuristic algorithms proposed in the past are dependent on algorithm-specific parameters for achieving an optimal solution.This paper proposes a hybrid algorithm of Jaya and a teaching–learning-based optimization(TLBO)named the JLBO algorithm for the optimal unit sizing of a PV–WT–battery hybrid system to satisfy the consumer’s load at minimal total annual cost(TAC).The reliability of the system is considered by a maximum allowable loss of power supply probability(LPSPmax)concept.The results obtained from the JLBO algorithm are compared with the original Jaya,TLBO,and genetic algorithms.The JLBO results show superior performance in terms of TAC,and the PV–WT–battery hybrid system is found to be the most economical scenario.This system provides a cost-effective solution for all proposed LPSPmax values as compared with PV–battery and WT–battery systems.

Optimal Configuration for Design of Stand-Alone PV System

This paper presents a design for a stand-alone photovoltaic (PV) system to provide the required electricity for a single residential household in rural area in Jordan. The complete design steps for the suggested household loads are carried out. Site radiation data and the electrical load data of a typical household in the considered site are taken into account during the design steps. The reliability of the system is quantified by the loss of load probability. A computer program is developed to simulate the PV system behavior and to numerically find an optimal combination of PV array and battery bank for the design of stand-alone photovoltaic systems in terms of reliability and costs. The program calculates life cycle cost and annualized unit electrical cost. Simulations results showed that a value of loss of load probability LLP can be met by several combinations of PV array and battery storage. The method developed here uniquely determines the optimum configuration that meets the load demand with the minimum cost. The difference between the costs of these combinations is very large. The optimal unit electrical cost of 1 kWh for LLP = 0.049 is $0.293;while for LLP 0.0027 it is $0.402. The results of the study encouraged the use of the PV systems to electrify the remote sites in Jordan.

Sizing and Siting of Battery Energy Storage Systems:A Colombian Case

This paper presents a mixed-integer linear programming(MILP)formulation for sizing and siting of battery energy storage systems(BESSs).The problem formulation seeks to minimize both operation costs and BESS investment.The proposed model includes restrictions of the conventional securityconstrained unit commitment problem,a piece-wise linear approximation to model power losses,and a linear model of hydro generation units.The proposed model is tested in a 6-bus test system and a 15-bus system representing the Colombian power system.For the two studied systems,simulation results show that the reduction of operation costs due to the installation of BESSs compensates the investments,under some of the considered technical cost cases.Additionally,results show that adequate sizing and siting of BESSs reduce renewable energy curtailment in the Colombian power system with high penetration of fluctuating renewable generation.

Selecting and optimal sizing of hybridized energy storage systems for tidal energy integration into power grid

The high penetration of renewable energy systems with fluctuating power generation into the electric grids affects considerably the electric power quality and supply reliability.Therefore, energy storage resources are used to deal with the challenges imposed by power variability and demand-supply balance.The main focus of this paper is to investigate the appropriate storage technologies and the capacity needed for a successful tidal power integration.Therefore, a simplified sizing method, integrating an energy management strategy, is proposed.This method allows the selection of the adequate storage technologies and determines the required least-cost storage capacity by considering their technological limits associated with different power dynamics.The optimal solutions given by the multi-objective evolutionary algorithm are presented and analyzed.

Provision of Ramp-rate Limitation as Ancillary Service from Distribution to Transmission System:Definitions and Methodologies for Control and Sizing of Central Battery Energy Storage System

The variability of the output power of distributed renewable energy sources(DRESs)that originate from the fastchanging climatic conditions can negatively affect the grid stability.Therefore,grid operators have incorporated ramp-rate limitations(RRLs)for the injected DRES power in the grid codes.As the DRES penetration levels increase,the mitigation of high-power ramps is no longer considered as a system support function but rather an ancillary service(AS).Energy storage systems(ESSs)coordinated by RR control algorithms are often applied to mitigate these power fluctuations.However,no unified definition of active power ramps,which is essential to treat the RRL as AS,currently exists.This paper assesses the various definitions for ramp-rate RR and proposes RRL method control for a central battery ESS(BESS)in distribution systems(DSs).The ultimate objective is to restrain high-power ramps at the distribution transformer level so that RRL can be traded as AS to the upstream transmission system(TS).The proposed control is based on the direct control of theΔP/Δt,which means that the control parameters are directly correlated with the RR requirements included in the grid codes.In addition,a novel method for restoring the state of charge(So C)within a specific range following a high ramp-up/down event is proposed.Finally,a parametric method for estimating the sizing of central BESSs(BESS sizing for short)is developed.The BESS sizing is determined by considering the RR requirements,the DRES units,and the load mix of the examined DS.The BESS sizing is directly related to the constant RR achieved using the proposed control.Finally,the proposed methodologies are validated through simulations in MATLAB/Simulink and laboratory tests in a commercially available BESS.

考虑氢能长短周期储能特性的电氢综合能源系统容量配置方法

为响应“双碳”目标以及分布式可再生能源就地消纳的实际需求,该文提出一种以风光新能源为主导的氢电耦合综合能源系统容量优化配置方法,以满足电热氢多元负荷需求,并实现系统多时间尺度源荷匹配。首先,建立了包含电池、短时储氢与季节性储氢协同的混合储能系统模型以及多时间尺度运行策略。该策略充分挖掘了电氢设备的短时协同调节潜力以及氢储的跨季能量互补能力,实现氢储的多尺度利用并提高系统运行灵活性。其次,针对基于传统典型场景方法难以描述长时间尺度储能设备跨周期运行特性的问题,提出基于时间序列聚合方法的典型场景生成方法,为容量配置模型提供兼顾短时波动与季节特性的时序连续场景,加快求解速度同时保证了求解的精确度。之后,基于典型场景以全生命周期投资成本最低为目标,考虑储能设备寿命衰减、新能源消纳率等因素,建立系统容量优化模型。最后,利用中国浙江某地实际算例验证了所提优化配置方法的有效性,结果表明在接近100%消纳率的条件下,相较于传统的电氢协同能量管理策略,所提策略能够降低21.3%的全生命周期投资。

基于NSGA-Ⅲ算法的分布式光伏储能系统优化配置方法

在电力系统“双高”背景下,可再生能源发电快速增长,对配电网稳定性构成挑战,研究储能优化配置对提高分布式光伏消纳能力及配电网经济可靠运行具有重要意义。针对配电网的电压支撑需求与经济运行需求,提出了一种基于NSGA-Ⅲ算法的分布式储能双层多目标优化配置方法。在外层选址定容模型中,以分布式储能的位置和容量为决策变量,综合考虑储能总成本、配电网电压偏移和负荷波动,以提升配电网电压稳定性与经济性;在内层优化运行模型中,以储能的充放电状态为决策变量,考虑储能安装后的运营收益,以提高经济性;利用电压稳定指数识别系统中电压稳定性薄弱的节点作为预选址节点,以提高求解效率。算例分析表明,该储能配置方案及运行优化策略可实现储能投资效益最优,有效改善电网电压质量和功率稳定性,提高配电网运行水平。

Optimizing the grain size and grain boundary morphology of (K,Na) NbO_(3)-based ceramics: Paving the way for ultrahigh energy storage capacitors

Relaxor dielectric ceramic capacitors are very attractive for high-power energy storage.However,the low breakdown strength severely restricts improvements to the energy storage density and practical application.Here,a strategy of designing small grain sizes and abundant amorphous grain boundaries is proposed to improve the energy storage properties under the guidance of phase field theory.0.925(K_(0.5)Na_(0.5))NbO_(3)-e0.075Bi(Zn_(2/3)(Ta_(0.5)Nb_(0.5))1/3)O_(3)(KNNe-BZTN)relaxor ferroelectric ceramic is taken as an example to verify our strategy.The grain sizes and grain boundaries of the KNNeBZTN ceramics are carefully controlled by the high-energy ball milling method and twoestep sintering strategy.Impedance analysis and diffusion reflectance spectra demonstrate that KNNeBZTN ceramics with a small grain size and abundant amorphous grain boundary exhibit a lower charge carrier concentration and higher band gap.As a consequence,the breakdown electric field of KNNeBZTN ceramics increases from 222 kV/cm to 317 kV/cm when the grain size is decreased from 410 nm to 200 nm,accompanied by a slightly degraded maximum polarization.KNNeBZTN ceramics with an average grain size of~250 nm and abundant amorphous grain boundaries exhibit optimum energy storage properties with a high recoverable energy density of 4.02 J/cm^(3) and a high energy efficiency of 87.4%.This successful local structural design opens up a new paradigm to improve the energy storage performance of other dielectric ceramic capacitors for electrical energy storage.

Hierarchical Sizing and Power Distribution Strategy for Hybrid Energy Storage System

This paper proposes a hierarchical sizing method and a power distribution strategy of a hybrid energy storage system for plug-in hybrid electric vehicles(PHEVs),aiming to reduce both the energy consumption and battery degradation cost.As the optimal size matching is significant to multi-energy systems like PHEV with both battery and supercapacitor(SC),this hybrid system is adopted herein.First,the hierarchical optimization is conducted,when the optimal power of the internal combustion engine is calculated based on dynamic programming,and a wavelet transformer is introduced to distribute the power between the battery and the SC.Then,the fuel economy and battery degradation are evaluated to return feedback value to each sizing point within the hybrid energy storage system sizing space,obtaining the optimal sizes for the battery and the SC by comparing all the values in the whole sizing space.Finally,an all-hardware test platform is established with a fully active power conversion topology,on which the real-time control capability of the wavelet transformer method and the size matching between the battery and the SC are verified in both short and long time spans.

Small and Mid-Size Pump-Turbines with Variable Speed

The stability of the grid is jeopardized with the large percentage of non-dispatchable renewables like wind power and also with increasing solar power. This creates various problems because these forms of energy are very volatile and difficult to predict. In most countries the in-feed of these sources must not be curtailed. In addition most of the renewables do not provide short circuit capacity and inertia in the same way as classical units and so further worsen the stability of the grid. The growing exploitation of wind and solar might be limited due to grid stability problems. In order to compensate those problems a large amount of reserve capacity is needed and therefore new technologies for electricity storage are required. Hydraulic pumped storage—the classical storage technology—has some disadvantages. These plants are in mountain regions often far away from wind farms. The distance to the wind farms mean additional loading for the already stressed grid and additional transmission losses. To compensate the very volatile wind energy, the pump input power should be varied continuously. This is so far only possible with variable speed units. Up to now double-fed asynchronous motor-generators are used which are rather expensive. In order to provide a solution for the described situation, ANDRITZ HYDRO has developed a new innovative concept of decentralized pump storage plants. Small standardized pump turbines are combined with a synchronous motor-generator and a full size converter which allows speed variation in pump and turbine mode over a wide range. These plants can be built locally close to wind farms and other sources to be balanced, allowing the increase of renewable energy without increasing the transmission line capacity. For the future smart grids this will be a key storage technology. This concept is reliable, innovative and more economic than other storage technologies.

Hydrogen Energy Storage System:Review on Recent Progress

A hydrogen energy storage system(HESS)is one of the many risingmodern green innovations,using excess energy to generate hydrogen and storing it for various purposes.With that,there have been many discussions about commercializing HESS and improving it further.However,the design and sizing process can be overwhelming to comprehend with various sources to examine,and understanding optimal design methodologies is crucial to optimize a HESS design.With that,this review aims to collect and analyse a wide range of HESS studies to summarise recent studies.Two different collections of studies are studied,one was sourced by the main author for preliminary readings,and another was obtained via VOSViewer.The findings from the Web of Science platform were also examined for amore comprehensive understanding.Major findings include the People’sRepublic of China has been active in HESS research,as most works and active organizations originate from this country.HESS has been mainly researched to support power generation and balance load demands,with financial analysis being the common scope of analysis.MATLAB is a common tool used for HESS design,modelling,and optimization as it can handle complex calculations.Artificial neural network(ANN)has the potential to be used to model the HESS,but additional review is required as a formof future work.From a commercialization perspective,pressurized hydrogen tanks are ideal for hydrogen storage in a HESS,but other methods can be considered after additional research and development.From this review,it can be implied that modelling works will be the way forward for HESS research,but extensive collaborations and additional review are needed.Overall,this review summarized various takeaways that future research works on HESS can use.

Multi-Objective Sizing of Solar-Wind-Hydro Hybrid Power System with Doubled Energy Storages Under Optimal Coordinated Operational Strategy

More and more attention has been paid to the high penetration of renewable energy in recent years.The randomness and intermittency of solar and wind energy make it an inevitable trend that renewables are coupled with energy storage technologies.Pumped hydro storage(PHS)is the most widelyused storage form in the power grid but the capacity is limited by geographic conditions.The concentrated solar power(CSP)plant with a thermal energy storage(TES)system can realize easier grid connections and effective peak shaving.Therefore,this paper proposes a solar-wind-hydro hybrid power system with PHS-TES double energy storages,and investigates the optimal coordinated operational strategy and multi-objective sizing.The optimal sizing problem which considers the minimum levelized cost of energy(LCOE)and loss of power supply probability(LPSP)as objectives is solved by multi-objective particle swarm optimization.Moreover,the seasonal uncertainties of renewables are considered by applying a scenario-based analysis using Kmeans clustering.Finally,a case study reveals the effectiveness of the coordinated operational strategy and double energy storages from the perspectives of economy and reliability.The comparisons of optimal sizing results show that the PV-WindCSP-PHS system decreases the LCOE by 19.1%compared to a PV-Wind-CSP system under the same LPSP,and reduces the LPSP compared to PV-Wind-PHS systems with limited reservoir capacity,which indicates that the proposed system with double energy storages has better economy and reliability performance compared to single storage.

兼顾新能源消纳与频率电压支撑的电池储能系统优化规划

随着新能源发电占比的逐步提升,电力系统消纳新能源发电的难度和压力增大,电网的频率和电压稳定性面临巨大挑战。通过在电网中配置电池储能系统,不仅可以提升新能源的消纳能力,还可以提升系统频率和电压的支撑能力。因此,研究电池储能系统优化规划方法,考虑储能在电力系统正常运行时用于新能源消纳,在紧急情况下对频率和电压进行快速支撑,从而提高储能利用率,降低系统成本。建立了考虑新能源消纳的电池储能系统协同规划模型,可得到输电网中集中式电池储能系统和配电网中分布式电池储能系统的选址定容结果。提出了一种兼顾频率和电压支撑的电池储能系统规划方法,分别对储能位置、无功功率容量、有功功率容量和能量容量进行优化规划。综合考虑储能的多重功能,构建其支撑系统调频调压的约束,建立了兼顾新能源消纳与频率电压支撑的电池储能系统优化规划模型,得到电池储能系统的最终选址定容结果。基于IEEE 24节点输电网和IEEE 33节点配电网设计算例系统进行仿真分析,验证了所提方法的有效性。

“双高”电力系统集中式储能选址定容规划策略

为解决“双高”电网储能选址规划问题,提出包括结构性、运行性两项一级指标及功率波动泰尔熵等6项二级指标的集中式储能选址规划指标体系,建立以熵权法、TOPSIS法为单一评价及模糊Borda法为组合评价的指标体系组合评价模型,获得储能最优选址节点。然后提出基于变分模态分解的混合储能容量配置法,对储能控制功率进行模态分解,根据Hilbert边际谱区分高、低频模态并重构,将高、低频信号能量功率值分别分配给功率型及能量型储能。通过某地区算例结果验证了所提规划策略的有效性。

内相粒径对现场混装乳化基质老化过程的影响

为研究内相粒径对现场混装乳化基质老化过程的影响,利用可程式高低温箱对乳化基质进行周期性储存来加速基质老化,使用激光粒度仪、光学显微镜、水溶法和数字黏度计测试乳化基质老化过程中的内相粒径、微观结构、硝酸铵析晶量及黏度的变化。测试结果表明:内相粒径为9.47μm的现场混装乳化基质在储存1个周期后就已严重析晶,在储存3个周期后硝酸铵析晶量为储存前的3.32倍,黏度增大45.72%。内相粒径为3.76μm的现场混装乳化炸药在储存2个周期后平均内相粒径增大为10.06μm,硝酸铵析晶量为储存前的1.43倍,黏度增大10.18%,储存3个周期后的硝酸铵析晶量为储存前的1.71倍,黏度增大14.48%,内相粒径越小,现场混装乳化基质的储存稳定性越好。在实际生产中,应根据混装车设备性能的实际情况,考虑基质泵送及其安全性,尽可能制备内相粒径约小于5μm、黏度合理的乳化基质,用以生产现场混装乳化炸药。

就地无常规电源支撑下考虑新能源基地频率稳定的储能优化配置方法

沙漠、戈壁、荒漠地区风-光-储基地建设是推动新能源规模化开发的主要模式。然而,就地无常规电源支撑场景下,新能源发电与直流协调能力不足,基地频率稳定等问题突出。该文在以控制为主导的新能源基地,依据风-光-储运行特性,构建合理的虚拟惯量,并进一步探究跟网型控制、构网型控制策略对频率响应的影响,建立含多种控制策略的频率响应模型。储能电站在快速频率响应及灵活性调节新能源波动方面有巨大的优势。在储能规划模型中,提出考虑直流运行方式的储能优化配置方法,并在典型运行场景下嵌入频率安全稳定性约束。基于西北地区新能源基地规划指南设置算例,验证所提模型的合理性与有效性。并进一步分析频率指标,直流运行方式,构网型、跟网型场站对储能配置的影响;所提储能规划方法在实现经济性配置的同时,能够保证基地频率的稳定性,为就地无常规电源支撑场景下储能配置提供了新思路。

基于净能力及二阶锥规划的分布式光储多场景协同优化策略

针对现有配电网中分布式光储调度模型存在资源协同不足、求解复杂等问题,提出了一种基于净能力及二阶锥规划的分布式光储多场景协同优化调度策略。通过引入储能接入配电网后的功率转移分布因子,提出一种基于系统净能力的储能最优选址计算方法;综合考虑储能的运行特性和分布式光伏的出力不确定性,建立以系统日综合成本和削峰填谷为目标的分布式光储多场景协同优化调度模型;利用二阶锥松弛和Big-M法对潮流约束、储能运行约束进行处理,将原规划模型转化为混合整数二阶锥规划问题。以IEEE 33节点系统和西北某实际系统为算例进行仿真分析,结果表明所提方法能在降低负荷峰谷差和日综合成本、平抑负荷波动的同时,显著提高对分布式光伏的消纳能力,验证了所提方法的有效性和可行性。

考虑电压-无功调节的台区互联装置规划方法

伴随分布式能源广泛接入低压配电网,其对配电网运行灵活性和消纳能力的要求不断提高。利用低压柔性互联装置将独立运行的低压配电台区分区互联,避免传统电压调节和无功补偿装置频繁动作。考虑到柔性互联装置造价昂贵,协同传统电压-无功调节装置,文中提出低压柔性互联装置的选址定容规划方法。首先,分析低压柔性互联装置拓扑和运行方式,建立其潮流模型。其次,建立低压柔性互联装置优化配置的双层规划模型,上层规划以年综合费用最小为目标,下层规划考虑电压-无功协调控制时间序列模型,以运行成本和电压偏差最小为目标,基于粒子群优化算法和混合整数二阶锥规划算法交替求解,得出配电系统最优柔性互联方案和最优运行方式。最后,在IEEE 33节点系统上进行实例分析,验证该双层规划算法的有效性。结果表明,所提方法能有效减少柔性互联装置的过度布置,同时减少由分布式能源频繁波动造成的运行成本。将模型凸化并线性化的方法明显提高了求解效率。