Evaluation of the behind-the-meter benefits of energy storage systems with consideration of ancillary market opportunities

In this study, we analyze behind the meter benefits and resiliency capability of the price-taking energy storage devices in order to understand the impact of the facility's electricity and thermal demand behavior, energy providers pricing structure, DER configuration, storage capacity, and facility criticality on the storage evaluation assessment. We develop an integrated design considering ancillary market opportunities that accounts for different facilities with variant thermal and electrical loads, different DER configurations and energy tariff structures.     

Optimal use of energy storage systems with renewable energy sources

This article proposes a multi-period optimization to study the technical and economic effects of the placement and use of Renewable Energy Sources (RES) and Energy Storage Systems (ESS) in an electrical network. As the RES penetrations increase, their inherent variability affects the actual amounts of energy dispatched, their contribution to decrease emissions of pollutants and greenhouse gases, and the overall welfare effects they may have. Moreover, to better harness the energy from renewable sources, both new methodologies and technologies need to be adopted, counteracting the variability and uncertainty of these sources. A possible solution to the challenges of RES adoption is the coupling to energy storage sources, either as dedicated facilities on the supply side, or supporting the accommodation of loads to the available generation on the demand side. This paper suggests an algorithm for network dispatch, aimed at answering some of fundamental changes in the way the system is managed and discusses analytical characteristics of the optimal solution.The proposed methodology is applied to a case study. Four scenarios are analyzed in their dispatches, estimating the welfare effects on the participants in the wholesale market for a modified IEEE 30-bus network with wind energy as the RES in penetrations close to 15%. The policy implications from the results obtained prove that, first, ESS can decrease the ramping necessary for load following, but not necessarily increase the amount of wind energy used, and second, congestion patterns in the electrical network play a crucial role in the final effectiveness of the RES and ESS. These are important insights into an ongoing debate on how to direct storage and renewable energy investments for a low carbon economy.     

区块链技术在电力交易中的应用与展望

区块链技术作为分布式记账技术,为能源互联网中的多方协作场景提供了信任基础,在能源互联网中的电力交易等领域已有一些应用尝试。首先,文中回顾了区块链技术在电力交易中的理论研究情况,总结了其在分布式能源交易、产权登记、商品溯源、交易信息共享等方面的工程应用现状。然后,基于区块链的应用价值模型和中国电力市场的发展需求,展望了区块链技术在电力批发市场、电力零售市场、分布式发电市场化交易、电力衍生品交易、源荷互动电力交易、市场主体信用评价等中的应用。最后,分析了区块链技术在实际应用中面临的运算性能、存储容量和信任构建等潜在问题,给出了针对性的解决思路。     

Texas electricity service crisis through an energy justice lens

The ongoing energy transition, including the rapid electrification of energy services, reinforces the importance of secure and reliable electricity infrastructure. Electricity as a critical energy carrier cuts across sectoral boundaries, including but not limited to public health, national security, education, and transportation. Electricity markets treat electricity as a commodity bought and sold in the different restructured markets of the United States and are a critical feature of power systems shaping the energy transition. However, current electricity market developments primarily rely on techno-economic indicators and fall short of incorporating ethical considerations to spur energy transition towards 100% renewable electricity as end-use energy. Even though electricity markets are designed based on the assumption that they are socially valuable, they essentially go unmeasured based on social and ethical parameters and are largely measured using technical and economic tools and criteria. These inadequacies in the development of electricity markets fail to provide energy and other allied services, particularly during and in the aftermath of a disaster, to the people who need them the most. This paper aims to provide an analytical framework using the foundational approach of energy justice for looking at the electricity market development. The paper utilizes the case of the Texas electricity market and its role in dealing with the electricity crisis in Texas during the winter storm of 2021 from the critical lens of energy justice. The paper shows that using the foundational approach of energy justice, the electricity market can be designed more ethically by considering electricity as means rather than only a market commodity.     

考虑电动汽车移动储能的微电网调度

将电动汽车电池集成到微电网可以为微电网提供额外的电能存储,其收益取决于市场电力价格、电动汽车充电状态和进站/出站率等因素.假设微电网由热力机组、可再生能源和含储能设施的停车场组成.文章提出了一种考虑电动汽车移动储能特性的能源管理优化模型,模型的目标函数是最小化预期的总运营成本,包括前期市场的能源购销成本、热力机组的启停...     

The Energy Bank-Roadmap for the 21st Century Green power grid

The electric power industry in the U.S. and the world is moving toward predominantly renewable energy. The electrical characteristics of most renewable resources are quite different than traditional generating systems. There is a transition from rotational generating resources to ones that are either static or electrically appear as static. The predominant renewable resources are expected to be wind and solar, where solar resources are expected to dominate due to their favorable economics. Wind and solar resources are non-dispatchable and their power production may not be coincident with demand. Storage resources therefore become an integral component of the 21^st century power grid.This article proposes a new vision, road-map and business model which the author calls the “Energy Bank” toward meeting the Green energy requirements of the electric power industry in the 21^st Century. The Energy Banks are envisioned to be private entities which collect and store energy at their own facilities or contract with private storage facilities within the entire power grid from transmission all the way to distribution and end consumers. This energy is then is made available for withdrawal by the depositor at a different time and location as well as in the form of physical and financial contracts to manage the price risks associated with wholesale markets.In the 21^st Century, similar to money, most of the population make energy, need to store it and like to use it at the different times and locations. The Author argues that Energy Banks as private market forces can facilitate energy transactions among vast number of renewable resources which will be needed by the 21^st Century Electric Power while creating a sustainable business model capable of exerting long-term pressure on the cost of electricity.     

Modernizing the energy infrastructure at federal facilities: Should utilities play a bigger role?

Since the Energy Policy Act of 1992, federal facilities have increasingly used performance contracting to finance energy and water efficiency measures. Utility Energy Performance Contracts (UESCs) have received less attention despite having similar goals and processes as Energy Savings Performance Contracts (ESPCs). This paper provides a comparison between the two performance contracting models and highlights the tradeoffs that should be considered. Higher costs observed in ESPCs are driven by higher overhead and the costs of savings guarantees. These cost drivers cascade into longer financing terms and higher interest rates. These results suggest that federal agencies should explore UESCs as a potentially more cost-effective way to achieve energy savings improvements.     

含偏差风险规避的新能源和储能协同参与市场策略

为了提高新能源发电效益,可利用储能配合新能源主动参与市场以获得更多盈利的机会,因此提出了含偏差风险规避的新能源和储能协同参与市场的运行模型。偏差风险被定义为日内弃电损失与惩罚费用之和,其源于新能源不确定性所产生的偏差功率。为了降低新能源参与市场交易的偏差风险,以新能源总期望收益最大为目标、以日前计划功率为变量、以储能最大充放电功率等为约束建立协同运行模型,通过场景分析法模拟新能源出力的不确定性,采用条件风险价值度量风险并引入风险规避因子。根据是否考虑预测偏差功率,提出以新能源发电功率预测值、以考虑预测偏差功率后的发电功率预测值作为申报功率上限的2种申报策略。算例分析结果表明：在所提2种申报策略中,考虑预测偏差功率的申报策略具有更高的综合效益,可为新能源提供重要参考;储能协同新能源参与市场可有效规避偏差风险,有利于推动新能源为主体的新型电力市场中能量市场和辅助服务市场的并重发展。     

储能商业化应用政策解析

我国储能产业正处于从政策层面向落实行动计划过渡的时期。在国家各类政策的指导下，各省市依据其区域特点在梯次回收、辅助调频、新能源发电等领域发布了相关政策，这在一定程度上加快了储能迈向商业化的步伐。就梯次电池回收利用、新能源发电、电力辅助服务、电价改革等方面梳理了国家层面以及地方的储能政策，分析了储能技术在应用领域、省市行动计划、企业示范工程的政策要点以及盈利模式。对目前的储能商业化进程给出相应的建议和展望，为今后提升储能效益价值有一定参考意义。     

含P2G和混合电储能的矿山综合能源系统多目标优化调度

为了提高分布式光伏消纳能力、优化矿山能源利用效率,提出一种基于电转气(P2G)技术和煤层气发电技术的光-储-气-废弃矿井抽蓄多能耦合矿山综合能源系统(MIES),该系统将弃光电量通过电解水制CH4作为煤层气发电的补充,并采用混合电储能平抑光伏出力波动.在对多能耦合MIES进行分析的基础上,构建矿山电、气、热、冷不同能源转换装置的数学模型,并以总运行成本和弃光电量最小为目标,建立MIES协调优化调度模型.不同运行场景下的调度结果表明,所提模型能实现协调调度,提高弃光电量的消纳,降低总运行成本.对不同储能模式下P2G和混合电储能装置之间互补协调能力的分析结果表明,所提模型能提升系统运行灵活性,实现能源最优经济利用.     

美国电力市场信息披露体系及其对中国的启示

从国家和区域电力市场两个层面,深入研究了美国电力市场信息披露体系。在国家层面,详细梳理了美国能源信息署对电力基本概况、电力生产与消费、电力市场运行、环境信息等的披露,并分析了其披露这些信息的制度考量。在区域电力市场层面,以PJM电力市场为例,详细梳理了其在能量市场、辅助服务等市场中披露的系统运行、市场价格、电力供需、成员报价、市场结构等信息,并分析了其披露这些信息的作用。在此基础上,结合中国国情,提出了以引导资源跨区域流动为核心的国家层面信息披露,以及以自证市场公信力、提高省内市场效率为核心的省级层面信息披露的政策建议。     

Statistical distribution for wind power forecast error and its application to determine optimal size of energy storage system

Accurate wind power forecast is an important tool for wind farm to participate in day-ahead or hours-ahead energy markets. However, forecast errors with any methodology are so large that they cannot be neglected. The forecast error needs to be analyzed individually for single wind farm to estimate the impact of this error on trading wind energy in electricity market. Although forecast error is always assumed as normal distribution, it can be demonstrated that it is not proper with a simple statistical analysis. In this paper, a mixed distribution is proposed based on laplace and normal distribution to model forecast errors associated with persistence forecast for single wind farm over multiple timescales. Then the proposed distribution is used to estimate the penalties for prediction errors in the electricity market. Energy storage system (ESS) can smooth the wind power output and make wind power more “dispatchable”. A probabilistic method is proposed to determine optimal size of ESS for wind farm in electricity markets. The results indicate that the proposed distribution and probabilistic method is efficient to find optimal size of ESS.     

压缩空气蓄能(CAES)电站及其现状和发展趋势

压缩空气蓄能(CAES)电站是一种新型电能存储系统,具有动态响应快、经济性能高、环境污染小等优点,可起到负荷平衡、战略规划、提高供电质量的作用。CAES电站包括压气机、电动机/发电机、地下贮气室、换热器、燃烧室、燃气轮机等常用设备,可分为两个子系统,分别是蓄能子系统和发电子系统。将介绍其工作原理,论述其应用前景,并对比压缩空气蓄能电站和其它蓄能方式的性能。     

考虑绿色证书交易的寡头电力市场均衡分析

可再生能源配额和可交易绿色证书制度作为一种基于市场机制的新能源扶持政策,得到越来越多的关注。该政策的引入会对电力批发市场的竞争产生重要影响,特别是绿色证书交易市场与电力批发交易市场之间存在复杂的相互影响关系。为了定量研究该影响关系,采用寡头竞争均衡理论,建立了一个考虑绿色证书交易市场和电力批发交易市场的两阶段联合均衡模型。在第1阶段,可再生能源发电商以供应函数模式参与证书市场竞争;在第2阶段,所有发电商以古诺模式参与批发市场竞争。该模型描述的均衡问题可以表示为一个具有均衡约束的均衡问题,可采用非线性互补方法来求解。最后,算例仿真重点研究不同配额要求下发电商在两个市场中的策略性行为及相互影响关系,表明在不同的配额要求下,可再生能源发电商会选择在不同市场中行使市场力,并导致电力批发市场价格与绿色证书市场价格上升。     

关于节能减排与电力市场的结合

为了加强中国的节能减排工作,2007年8月国务院颁发了《节能发电调度办法(试行)》,该办法规定按排队法优先安排清洁能源发电,常规火力发电厂按等微增率法发电。文中试图分析如何将节能发电调度与中国电力市场改革工作相结合,达到既节能又有利于电力市场改革的效果,并探讨了考虑节能调度的日前发电计划,计费与补偿,年度、季度与月度计划,平衡市场,双边合同,配电市场,节能发电调度电力市场与常规电力市场的比较等问题。     

批发电力市场中清洁能源发电及调度——美国的经验

近几十年,美国的电力市场经历了几个阶段的改革,逐步形成了由供需决定批发电价的电力市场。近年来,清洁能源高速发展,美国电力市场也随之发展变革,形成了许多适应清洁能源发电特性的市场机制。在探讨美国电力市场定价机制的基础上,从市场机制和调度决策结合的角度,分析美国鼓励可再生能源发展的政策和清洁能源调度的经验与实践,总结了对中国清洁能源调度的启示。     

计及电价不确定性和损耗成本的储能竞价策略

储能是促进新能源消纳、提高电力系统稳定性和灵活性的有效措施。然而储能参与电力市场的策略极其复杂,现已成为实现储能商业化应用的关键问题之一。文中提出储能在日前和实时市场价格不确定环境下考虑循环损耗成本的最优竞价策略。为权衡储能多次循环增加的售电利润和损耗成本,在制定储能竞价策略时,将其循环损耗成本的影响计及在内,并充分考虑电池充、放电深度对循环损耗成本和利润的影响;在日前市场中建立电价-电量投标模型,对电价和电量同时进行投标以充分考虑电价不确定性;在实时市场中建立电量投标模型对日前市场投标进行弥补修正,使竞价策略更加合理与优化。算例验证了所提储能竞价策略的有效性,并说明所建模型可以确定最优电池充、放电深度。     

分布式储能商业模式分析与展望

在“双碳”政策背景下，构建新型电力系统已经成为我国一项重要战略性工程。储能因其对新能源消纳的促进作用已经成为构建新型电力系统的重要支撑手段。相较于集中式储能，分布式储能更加灵活便利，更易实现分布式能源的就地消纳。虽然分布式储能对于构建新型电力系统有众多益处，但是目前国内仍缺少可靠的商业运营模式使得分布式储能得到商业规模化发展。因此，有必要对分布式储能的商业运营模式进行探讨分析。首先从政策层面以及项目实践层面上论述当下分布式储能被市场认可的商业价值。其次结合国内的政策环境以及国内外相关项目的实践经验，对分布式储能较为成熟的4种商业模式进行梳理探讨。最后，基于分布式储能的核心商业价值以及其资源分散的物理特点，对分布式储能未来的商业运营模式作出进一步地展望。     

A study of economic evaluation of demand‐side energy storage system in consideration of market clearing price

In Japan the electricity market will open on April 1, 2004. Electric utility, Power Producer and Supplier (PPS), and Load Service Entity (LSE) will join the electricity market. LSEs purchase electricity based on the Market Clearing Price (:MCP) from the electricity market. LSEs supply electricity to the customers that contracted with the LSEs on a certain electricity price, and one to the customers that introduced Energy Storage System (:ES) on a time‐of‐use pricing. It is difficult for LSEs to estimate whether they have any incentive to promote customers to introduce ES or not. This paper evaluates the reduction of LSEs' purchasing cost from the electricity market and other LSEs' purchasing cost by introducing ES to customers. It is clarified which kind of customers has the effect of decreasing LSEs' purchasing cost and how much MCP of the whole power system the demand‐side energy storage systems change. Through numerical examples, this paper evaluates the possibility of giving the cost merit to both customers with energy storage systems and LSE by using real data for a year's worth of MCP. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(1): 22–35, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20447     

How can energy storage catalyze GCC electricity policy? Issues and options

Saudi Arabia and other Gulf Cooperation Council (GCC) members have a parallel agenda of electricity market reforms together with ambitious goals of renewable energy deployment. The motivation for this agenda is multifaceted and extends beyond increasing economic efficiency. Renewable integration raises market and regulatory design issues for countries transitioning to markets and high levels of renewables though. This difficulty or perhaps even incompatibility may undercut both policies’ objectives. This paper analyses the implications of deploying new energy storage in this context. Although storage services would facilitate the integration of renewables and market restructuring policies, deploying this novel technology would raise additional regulatory issues in the electricity sector. Ignoring these regulatory challenges could not only lead to unnecessary costs of transition but also make it more difficult to obtain the full benefits of other economic policy objectives such as the removal of subsidies to relieve public finances and the release oil for sale in international markets.