On Some Issues of Assessing the Efficiency of Renewable Energy Power Plants and the Share of Renewables in the World＇s Electricity Generation

The paper considers some issues related to the evaluation of power plants using renewable energy sources： energy efficiency, economic efficiency, the share of renewable energy in the world＇s electricity generation. At one time in the world there was a myth that more energy is expended on the construction of wind and photoelectric power stations, than they produce for the service life. Adherents of this myth are still found in Russia. In response to this myth, numerous studies have been carried out for the manufacturers of wind turbines and photovoltaic modules. It was proved that these power plants spent energy on them are produced within a period of less than a year and the energy consumed by them cannot be taken into account, since it is renewable. The author showed that power plants on organic fuel and existing nuclear plants using depleted fuel with a coefficient less than unity fundamentally cannot compensate for the energy used during their construction. In the world, the concept of the LEC （Levelized Energy Cost） produced by any power plant is widely used to estimate economic efficiency. However, the formula for determining it, in the author＇s opinion, contains an inaccuracy, which is proposed to be eliminated. At present, there are different opinions on the role of RES （Renewable Energy Sources） in the production of electricity. A summary indicator is the share of renewable energy in the world＇s electricity generation. The determination of the actual share of RES and the forecast of its growth is of significant importance for the development of the world economy. The author shows the differences in the estimates and suggests an approach for establishing agreed estimates.

State-of-the-Art Analysis and Perspectives for Peer-to-Peer Energy Trading

As a promising solution to address the“energy trilemma”confronting human society,peer-to-peer(P2P)energy trading has emerged and rapidly developed in recent years.When carrying out P2P energy trading,customers with distributed energy resources(DERs)are able to directly trade and share energy with each other.This paper summarizes and analyzes the global development of P2P energy trading based on a comprehensive review of related academic papers,research projects,and industrial practice.Key aspects in P2P energy trading are identified and discussed,including market design,trading platforms,physical infrastructure and information and communication technology(ICT)infrastructure,social science perspectives,and policy.For each key aspect,existing research and practice are critically reviewed and insights for future development are presented.Comprehensive concluding remarks are provided at the end,summarizing the major findings and perspectives of this paper.P2P energy trading is a growing field with great potential and opportunities for both academia and industry across the world.

Trading platform for cooperation and sharing based on blockchain within multi-agent energy internet

With the release of the electricity sales side,large-scale small-capacity distributed power generation units are connected to the distribution side,forming multi-type market entities such as microgrids,integrated energy systems,and virtual power plants.With the large-scale integration of distributed energy,the energy market under the energy internet is different from a traditional transmission grid.It is currently developing in the direction of diversified entities and commodities,a flat structure,and a flexible and competitive multi-agent market mechanism.In this context,this study analyzes the value of combining blockchain and the electricity market presents the design of a blockchain trading framework for multi-agent cooperation and sharing of the energy internet.The nodes in market transactions are modeled through power system modeling in the physical layer and the transaction consensus strategy in the cyber layer;moreover,the nodes are verified in a modified IEEE 13 testing feeder of a distribution network.A transaction example is demonstrated using the multi-agent cooperation and sharing transaction platform based on the Ethereum private blockchain.

Peer-to-peer Electricity Transaction Decisions of the User-side Smart Energy System Based on the SARSA Reinforcement Learning

With the deep integration of advanced information technologies,such as artificial intelligence and traditional energy technologies,smart energy systems have been proposed as a method to provide the best solution for the coordination,balance,and control of the entire energy system.As a new way of energy balance and interaction in the user side energy market,a peer-to-peer(P2P)electricity transaction can effectively promote energy sharing within the user group and improve the economic benefits of users participating in the energy market.Reinforcement learning(RL)is an artificial intelligence method in which agents continuously acquire relevant experience and knowledge during the interaction with the environment,automatically update their decision-making behavior;and achieve maximum return.It is a suitable approach for P2P transaction decision analysis of small-scale users in the context of smart energy.First,this paper establishes a P2P transaction model that includes a participant model,equipment model and price model.Secondly,the transaction problem is equivalent to a Markov decision process(MDP)and each learning element model is established.Then,the MDP problem is solved and analyzed using the SARSA RL algorithm with average discrete processing.Finally,a case study of a community with multiple users is conducted to verify the effectiveness,economy,and security of the RL method in solving energy storage action selection and transaction decision problems of energy storage users.

考虑储能租赁的光伏集群公共品演化博弈分析

在迈向新型电力系统和推进光伏产业发展的过程中,为实现碳达峰、碳中和的发展目标,各地陆续出台了强制配置储能的考核制度。为稳定光伏出力的同时提高储能资源的利用效率,本文基于共享经济的商业模式构建双层博弈优化模型,探究光伏电站集群储能租赁配置问题。上层以储能运营商为领导者,以光伏电站集群用户为跟随者,建立主从博弈模型来优化租赁价格策略;面向光伏电站集群内部合作情况,下层基于阈值建立公共品演化博弈,并通过奖惩措施促进光伏电站租赁储能和优化储能租赁配置容量,进而解决合作困难问题。仿真结果表明,适当的激励和处罚措施有利于促进光伏电站集群对储能的租赁与配置,确保满足电网公司对储能配置的强制性要求;基于双层博弈模型框架的主从博弈定价策略,有利于协调储能运营商和光伏电站集群及储能租赁用户之间的利益,促成各方在经济利益上的合作共赢。

Cloud-edge-based We-Market:Autonomous Bidding and Peer-to-peer Energy Sharing Among Prosumers

With the extensive penetration of distributed renewable energy and self-interested prosumers,the emerging power market tends to enable user autonomy by bottom-up control and distributed coordination.This paper is devoted to solving the specific problems of distributed energy management and autonomous bidding and peer-to-peer(P2P)energy sharing among prosumers.A novel cloud-edge-based We-Market is presented,where the prosumers,as edge nodes with independent control,balance the electricity cost and thermal comfort by formulating a dynamic household energy management system(HEMS).Meanwhile,the autonomous bidding is initiated by prosumers via the modified Stone-Geary utility function.In the cloud center,a distributed convergence bidding(CB)algorithm based on consistency criterion is developed,which promotes faster and fairer bidding through the interactive iteration with the edge nodes.Besides,the proposed scheme is built on top of the commercial cloud platform with sufficiently secure and scalable computing capacity.Numerical results show the effectiveness and practicability of the proposed We-Market,which achieves 15%cost reduction with shorter running time.Comparative analysis indicates better scalability,which is more suitable for largerscale We-Market implementation.

计及光伏和储能接入的牵引供电系统能量管理策略

近年来,为实现电气化铁路“双碳”目标,多项铁路用能优化举措投入实施并取得一定成效,然而,单靠能耗优化治标不治本。为根治电气化铁路碳排放问题,在保证系统稳定运行的基础上,基于智能电网理念,提出计及光伏和储能接入的牵引供电系统能量管理策略。首先,构建计及光伏和储能接入的牵引供电系统;然后,基于电力市场电价及新能源出力,采用日前联合调控、日内滚动调节和实时优化控制铁路用能,并通过分层分级优化,打破各“源”端相对独立、各自为政的壁垒,实现多能互补;最后,通过共享储能模式,降低储能装置闲置率并提高新能源利用率。仿真结果表明,该能量管理策略可在保障系统运行稳定和安全的基础上有效地降低系统的运行成本,同时保持良好的电能质量。

基于输入均压与虚拟直流电机相结合的直流电能路由器控制策略

针对中压直流配电网接入下的直流电能路由器在新能源出力等工况下,使用传统控制策略对直流母线的控制效果一般、电压易越限等问题,基于模块化的输入串联输出并联(input-series output-parallel,ISOP)型拓扑结构,提出一种基于输入均压与虚拟直流电机相结合的直流电能路由器控制策略。首先,研究输入均压控制过程中模块间的功率均衡控制特性并与输出均流控制进行比较;接着,将虚拟直流电机控制应用到控制算法中,使变流器模拟出直流电机的惯性特性;然后,对虚拟直流电机建立小信号数学模型,分析其工作机理以及参数对系统的影响;最后,在MATLAB/Simulink中搭建仿真模型进行验证。结果表明:所提控制策略能够在实现直流电能路由器各模块间功率均衡的同时,具有类似直流电机的惯量特性与阻尼特性,可显著提高直流配电网直流母线电压稳定性。

考虑新能源发电商租赁共享储能的电力市场博弈分析

针对实际中储能资源利用率不高等问题,提出一种新能源发电商和储能运营商之间的储能租赁共享模式,其中储能运营商除了租赁部分储能给新能源发电商外,还可利用剩余储能独立参与市场竞争,因而该模式有助于提高储能资源利用率。为了研究该共享模式对电力市场运行的影响,建立了考虑该共享模式的日前电力市场双层博弈模型,其中,上层为储能运营商与多个新能源发电商基于讨价还价博弈理论来确定储能租赁价格的优化模型,下层为新能源发电商、储能运营商与传统发电商作为价格影响者参与日前电力市场竞争的多时段非合作博弈模型。然后采用非线性互补方法将双层博弈模型转化为单层优化问题求解。最后通过算例仿真验证所提出租赁模式的合理性和有效性。

共享储能模式下电动汽车充电站双层优化运行策略

在电动汽车持有量快速增长的背景下,电动汽车充电站的建设需求日益强烈。为了提高充电站运行经济性,文中提出接入共享储能的电动汽车充电站优化调度方法。首先,分析分布式储能和共享储能的运行模式,以充电站年投资成本和年运行成本最低为上层目标函数,以典型日运行成本最小为下层目标函数,构建考虑储能不同运行模式的电动汽车充电站双层优化调度模型。其次,对3个具有差异性的电动汽车充电站进行仿真,并将多个场景下的不同储能运行模式进行对比。然后,在此基础上,针对共享储能服务费以及电动汽车放电损耗进行灵敏度分析。最后,算例表明,共享储能的接入对降低电动汽车充电站规划和运行成本具有积极作用,合理的储能服务费定价和电动汽车放电损耗成本能减少充电站运行成本。

基于共享通道的双向无线电能和信息同时传输系统特性研究

随着电力电子技术、控制技术及开关电源相关技术的发展,电能和信号传输逐渐从以电缆为传输媒介的传统传输方式逐渐向无线传输方向发展。对于需要在水介质中长时间工作的电气设备而言,能量供应是维持其正常工作的关键因素,但由于电缆进行物理连接的传统传输方式在水介质中运用较为不便,并且存在较大的安全隐患,因此需要构建一个基于共享通道的双向无线电能和信息同时传输的系统。

市场环境下考虑全周期经济效益的工业园区共享储能优化配置

为提升用户侧储能运行效率、改善投资成效,提出一种在市场环境下考虑全周期经济效益的工业园区共享储能(SES)优化配置方法。一方面,通过协调不同用户间的差异化调节需求,减少储能容量要求;另一方面,通过整合用户与SES的灵活调节能力,参与需求响应市场拓宽盈利渠道,并且考虑了SES全运行周期经济效益测算以降低投资风险。首先,结合电力市场交易规则,提出了多工业用户组建合作联盟的园区SES运营模式。其次,以运营周期内联盟总成本最小为目标,建立SES双层优化配置模型,其中,上层模型旨在形成最大化投资成效的SES规划方案,而下层模型则综合考虑分时电价、需求响应违约风险等因素形成储能的最优投标调度方式,并结合市场时序演变规律精准量化SES在全运行周期内的运营收益,对上层结果进行修正。接着,利用近似KKT(Karush-Kuhn-Tucker)条件将该模型转化为单层模型进行求解,结合雨流计数法与迭代法量化SES容量衰减对其配置方案的影响,并利用双边Shapley值法分摊各工业用户的投资成本。最后,算例仿真验证了所提方法的有效性,并且分析了储能盈利模式、SES容量衰减以及需求响应违约风险等因素对SES投资经济效益的影响。

基于混合博弈的多区域电-储共享运营模式与经济效益分析

随着用户侧新能源设备与储能装置的广泛接入,如何有效地促进新能源本地消纳与降低储能运行成本变得至关重要。针对多区域间电能与储能资源的共享问题,提出了一种基于主从-演化混合博弈的多区域电能-储能共享运营模式。首先,建立主从博弈模型和演化博弈模型进行优化决策。运营商作为领导者根据各区域供需平衡情况,制定区域内部电价;用户作为跟随者,根据区域电价与跨区交易传输费用信息,基于演化博弈模型调整自身用电量与区域选择概率。其次,考虑到各主体利益诉求不同,建立了运营商和用户的收入与成本模型,并以最大化双方收益、最小化与电网交互电量为目标函数,得到运营商的定价策略、共享储能配置与充放电策略,以及各主体的最终收益。最后,通过算例分析验证了所提运营模式的有效性。

基于分布鲁棒优化的广义共享储能容量配置方法

共享储能通过储能资源的复用,能有效应对高成本和利用率低的难题。迅速发展的需求侧资源在共享储能中具有潜在应用,但其不确定性问题亟待解决。文中引入了电动汽车和温控负荷的虚拟储能模型,结合实体储能,建立了考虑不确定性的广义共享储能模型和相应的优化算法,以确定实体储能的最佳容量配置。共享储能运营商根据用户需求,实现多类型储能的优化配置,并设计虚拟储能持有者的满意度补偿,以保障其用户体验和经济利益。此外,采用Wasserstein距离描述电动汽车和温控负荷的不确定性,并结合基于风险价值的分布鲁棒机会约束算法进行求解。算例结果表明,采用广义共享储能模型和分布鲁棒机会优化算法,能够充分考虑不确定性,有效降低用户的能源消费成本和运营商的储能配置成本。

基于机会约束的售电公司共享储能经济运行优化

针对自有共享储能的售电公司的经济运行优化问题,从产消者共享售电公司所投资共享储能的角度,研究了一种售电公司的新型商业模式。考虑源侧与荷侧的不确定性因素,建立了售电公司共享储能服务运营策略的主从博弈模型,其上层负责求解售电公司最优共享储能服务定价和购售电策略问题,下层负责求解产消者最优运行策略问题,并基于机会约束模型描述源、荷不确定性。根据下层的KKT条件将下层模型转化为上层模型的约束条件,并利用大M法对非线性约束进行线性化。基于3个典型场景算例验证所提新型交互模式的可行性,分析售电公司共享储能服务定价方法和不确定性因素对收益的影响。

计及共享储能与光伏的园区多用户综合收益优化

针对含共享储能与户用光伏的园区场景,文中提出一种用户侧综合收益双层优化方法,充分挖掘共享储能灵活性及用户用电需求差异性,在实现用户整体经济效益最优的同时提升光伏消纳能力。模型上层为月前优化阶段,以用户月度用电成本最低为目标,考虑系统能量平衡、储能充放电约束以及储能荷电状态约束,优化工业用户最大用电功率,降低需量电费;模型下层为日前优化阶段,综合考虑用户综合收益及光伏消纳能力,以上层优化结果为约束条件,兼顾功率、储能等约束,提出共享储能充放电功率及用户与电网交互功率等日前优化策略,在用户月度整体经济性最优的前提下,实现用户侧每日经济效益的优化。最后,以南方某实际园区作为算例验证了文中所提方法的有效性。

基于主从博弈的园区多主体能量-碳配额共享机制

目前,电力系统主要通过激励源侧发电企业清洁改造以减少碳排放量,但仍有相当数量的碳排放暂时无法被削减。挖掘配网侧终端用户的碳减排潜力,是促进电力系统碳减排的有力手段。然而,现阶段配网侧低碳策略往往是通过碳排放成本传导或价格引导等经济策略实现的“被动碳减排”。如何疏导发电侧碳成本,激励用户深度减排是提升电力系统总碳减排量的关键问题。该文基于电碳耦合视角,提出园区点对点(peer-to-peer,P2P)电-碳共享新型商业模式,构建考虑碳交易的园区运营商和用户的效用模型,搭建了融合信息流、能量流、碳流的P2P能量-碳配额共享机制;然后,基于斯塔克伯格主从博弈框架设计最优能源-碳定价模型,优化引导园区用户能量与碳配额共享;最后,通过算例证明了方法的有效性。结果表明,该文提出的共享框架与模型能够优化园区内能源与碳的定价,激励用户参与共享,在提升多能源园区的新能源消纳率的同时进一步减少园区碳排放。

计及动态能源价格和共享储能电站的多主体综合能源系统双层优化调度策略

可再生能源不确定性背景下,为协调综合能源运营商、电热负荷聚集商及共享储能电站之间的利益关系,提出一种电热综合动态定价机制,基于综合需求响应特性,引导电热负荷聚集商参与综合能源系统运营商优化,促进储能高效应用和新能源就地消纳,实现多利益主体互利共赢。以综合能源系统运营商为主体,以电热负荷聚集商和共享储能运营商为从体,构建一主多从的综合能源多运营主体系统优化模型。充分挖掘共享储能运营商的运行模式,包括充电、放电和提供备用等模式。采用CPLEX对主从博弈模型迭代求解,算例结果验证了模型及方法的有效性。

Real-Time Energy Management for Net-Zero Power Systems Based on Shared Energy Storage

Battery energy storage systems(BESSs)serve a crucial role in balancing energy fluctuations and reducing carbon emissions in net-zero power systems.However,the efficiency and cost performance have remained significant challenges,which hinders the widespread adoption and development of BESSs.To address these challenges,this paper proposes a real-time energy management scheme that considers the involvement of prosumers to support net-zero power systems.The scheme is based on two shared energy storage models,referred to as energy storage sale model and power line lease model.The energy storage sale model balances real-time power deviations by energy interaction with the goal of minimizing system costs while generating revenue for shared energy storage providers(ESPs).Additionally,power line lease model supports peer-to-peer(P2P)power trading among prosumers through the power lines laid by ESPs to connect each prosumer.This model allows ESP to earn profits from the use of power lines while balancing power deviations and better consuming renewable energy.Experimental results validate the effectiveness of the proposed scheme,ensuring stable power supply for net-zero power systems and providing benefits for both the ESP and prosumers.

供需自我平衡的全网客户储能系统浅议

为促进供需平衡以及削峰填谷,保证电力系统稳定,文章提出回归供需平衡的全网客户储能系统。开发以用电客户为单元的储能系统,根据新能源与常规能源电力出力特征,削峰填谷,峰充谷发,藏电于民,维护电力协调持续稳定供应。这不仅可以从源头解决供需平衡问题,更重要的是可以发挥动力电池明显的储能技术优势。