Short-term Scheduling of Steam Power System in Iron and Steel Industry under Time-of-use Power Price

A generalized formulation for short-term scheduling of steam power system in iron and steel industry under the time-of-use（TOU）power price was presented,with minimization of total operational cost including fuel cost,equipment maintenance cost and the charge of exchange power with main grid.The model took into account the varying nature of surplus byproduct gas flows,several practical technical constraints and the impact of TOU power price.All major types of utility equipments,involving boilers,steam turbines,combined heat and power（CHP）units,and waste heat and energy recovery generators（WHERG）,were separately modeled using thermodynamic balance equations and regression method.In order to solve this complex nonlinear optimization model,a new improved particle swarm optimization（IPSO）algorithm was proposed by incorporating time-variant parameters,a selfadaptive mutation scheme and efficient constraint handling strategies.Finally,a case study for a real industrial example was used for illustrating the model and validating the effectiveness of the proposed approach.

Price prediction of power transformer materials based on CEEMD and GRU

The rapid growth of the Chinese economy has fueled the expansion of power grids.Power transformers are key equipment in power grid projects,and their price changes have a significant impact on cost control.However,the prices of power transformer materials manifest as nonsmooth and nonlinear sequences.Hence,estimating the acquisition costs of power grid projects is difficult,hindering the normal operation of power engineering construction.To more accurately predict the price of power transformer materials,this study proposes a method based on complementary ensemble empirical mode decomposition(CEEMD)and gated recurrent unit(GRU)network.First,the CEEMD decomposed the price series into multiple intrinsic mode functions(IMFs).Multiple IMFs were clustered to obtain several aggregated sequences based on the sample entropy of each IMF.Then,an empirical wavelet transform(EWT)was applied to the aggregation sequence with a large sample entropy,and the multiple subsequences obtained from the decomposition were predicted by the GRU model.The GRU model was used to directly predict the aggregation sequences with a small sample entropy.In this study,we used authentic historical pricing data for power transformer materials to validate the proposed approach.The empirical findings demonstrated the efficacy of our method across both datasets,with mean absolute percentage errors(MAPEs)of less than 1%and 3%.This approach holds a significant reference value for future research in the field of power transformer material price prediction.

Flexible Load Participation in Peaking Shaving and Valley Filling Based on Dynamic Price Incentives

Considering the widening of the peak-valley difference in the power grid and the difficulty of the existing fixed time-of-use electricity price mechanism in meeting the energy demand of heterogeneous users at various moments or motivating users,the design of a reasonable dynamic pricing mechanism to actively engage users in demand response becomes imperative for power grid companies.For this purpose,a power grid-flexible load bilevel model is constructed based on dynamic pricing,where the leader is the dispatching center and the lower-level flexible load acts as the follower.Initially,an upper-level day-ahead dispatching model for the power grid is established,considering the lowest power grid dispatching cost as the objective function and incorporating the power grid-side constraints.Then,the lower level comprehensively considers the load characteristics of industrial load,energy storage,and data centers,and then establishes a lower-level flexible load operation model with the lowest user power-consuming cost as the objective function.Finally,the proposed method is validated using the IEEE-118 system,and the findings indicate that the dynamic pricing mechanism for peaking shaving and valley filling can effectively guide users to respond actively,thereby reducing the peak-valley difference and decreasing users’purchasing costs.

Optimal Time-of-use Pricing for Renewable Energy-powered Microgrids: A Multi-agent Evolutionary Game Theory-based Approach

While price schedules can help improve the economic efficiency of renewable energy-powered microgrids,timeof-use(TOU)pricing has been identified as an effective way for microgrid development,which is presently limited by its high costs.In this study,we propose an evolutionary game theoretic model to explore optimal TOU pricing for development of renewable energy-powered microgrids by applying a multi-agent system,that comprises a government agent,local utility company agent,and different types of consumer agents.In the proposed model,we design objective functions for the company and the consumers and obtain a Nash equilibrium using backward induction.Two pricing strategies,namely,the TOU seasonal pricing and TOU monthly pricing,are evaluated and compared with traditional fixed pricing.The numerical results demonstrate that TOU schedules have significant potential for development of renewable energy-powered microgrids and are recommended for an electric company to replace traditional fixed pricing.Additionally,TOU monthly pricing is more suitable than TOU seasonal pricing for microgrid development.

House Price, Consumption Power and Gap of Demographic Urbanization in China

This paper investigates the gap of demographic urbanization arising from the difference between rural residents who have migrated to cities and those who have acquired urban citizenship in the process of China's urbanization. The skyrocketing house prices and insufficient household consumption power are key factors to the widening gap, which had reached 18% in 2013. In order to explore this issue, by creating the basic model and the model with interaction term, this paper has analyzed the relationship among house prices, consumption power and gap of urbanization using the data of 31 provinces between 1999 and 2013 in China. Empirical result indicates that: there is a positive correlation between the house prices and the gap of China's demographic urbanization. However, such a correlation is restrained by these rural migrants who rent houses in cities. For an increase of house price by 1%, the gap of urbanization will widen by 1.05%. Although rising urban consumption power of rural residents has increased the ratio of migration, the lagged growth of consumption power has led to a widening gap of urbanization. Therefore, the only way to effectively reduce the gap of demographic urbanization is to increase the consumption power of migrant population and optimize consumption structure.

Impact of Electric Vehicle Charging on Power Load Based on TOU Price

Large-scale electric vehicle charging has a significant impact on power grid load, disorderly charging will increase power grid peak load. This article proposes an orderly charging mechanism based on TOU price. To build an orderly charging model by researching TOU price and user price reaction model. This article research the impact of electric vehicle charging on grid load by orderly charging model. With this model the grid’s peak and valley characteristics, the utilization of charging equipment, the economics of grid operation can all be improved.

Impacts of a Japan–South Korea power system interconnection on the competitiveness of electric power companies according to power exchange prices

In many regions,international power system interconnections provide economic,energy-security,environmental,and technical benefits.In contrast,such interconnections remain scarce in Northeast Asia.In 2016,after approving a joint memorandum of understanding between major electric power companies from China,Japan,South Korea,and Russia,related initiatives regained momentum in the region.Nevertheless,the corresponding developments in Japan remain limited,mainly owing to the lack of involvement of Japanese electric power companies.This study represents a pioneering attempt to provide an economic assessment based on power exchange prices of a power system interconnection between Japan and South Korea regarding the competitiveness of electric power companies in terms of competitive business segments and strategic consequences.We found that although the position of Japanese generators may slightly deteriorate,that of the supply segment would substantially improve,thus suggesting that more opportunities than threats are derived from the interconnection.This promising outcome may foster the adoption of an interconnection with South Korea considering the positive economic and business perspectives in Japan.Furthermore,realizing the interconnection may improve the energy security and air quality in the region.

Primary Study of Power-Exchanging Trans- action Model Among Price-Varied Power Plants in Practical Conditions

At present, electricity price to grid of domestic power plants is priced by the national administration based on the policy of "one power plant with one electricity price to grid," which is difficult to realize real bidding for access to grid in practice in a short term. This paper presents one kind of power-exchanging transaction model among price-varied power plants, which will be beneficial to price-varied power plants without any loss of profits of them and guarantee state-owned assets profits in minimum loss with no promotion of average price limit by power plants. Under ideal conditions, the computation results showed the sufficiency and necessity of power-exchanging transaction and maximum similarity with the requirements of optimized resources disposition in economics. The presented model is shown to be full of practicability and has been used in some part of power market.

How to Realize Power Price Reduction in China?

In order to make power price truly reflect the cost of electric power and a reasonable profit without making the price unaffordable to the public, the government would have to adopt measures including tax reduction, surcharge reduction, debt relief and coal price reduction.

Double Pressure on Power Grids——The demand for electricity is dropping while the electricity price is not adjusted properly

Since October 2008,China's social consumption of electricity had,for the first time,grown negatively compared to the same period of the previous year,and in November the negative growth range further expanded. The major pressure faced by the electricity industry has now turned from the contradiction between coal and electricity to electricity quantity. This is undoubtedly a true and new test to electricity enterprises which get used to high growth but are now suffering great losses. The reform of electricity system has already been in great difficulties and now is getting into a more serious situation. In order to help readers improve their knowledge and understanding of the current tough situation faced by the electricity industry and discuss how to alleviate and get through the difficulty resulted from the economic crisis "encountered once every one hundred years" by joint efforts of all parties concerned,a Seminar on Crisis and Countermeasures for Electricity Industry was held on November 20,2008. Here are some extracts from the speeches of four experts.

Goal and Progress of Power Tariff Reform——An interview with Liu Zhenqiu,Vice Director ofDepartment of Price,NDRC

● Power tariffreform has made many important and substantialprogresses in respect ofmarketization● The benchmark tariff is a revolutionary progress made in China's power tariff reform● Coal-electricity price linkage is a transitional approach which needs further improvement● The principle of T&D pricing is "cost plus profit," but it can also be based on pro rata control● China's electricity market should choose the mode of bilateral contracting combined withcentralized market● The direction of the power tariff reform is that electricity price shall be controlled mainly by the re-lationship between supply and demand in the

A Study on Renewable Power Pricing Mechanism and Price Incentive Policies in China

The basic framework of price policies for promoting renewable power de- velopment in China is introduced. The background, concept and implementation of price policies, focused on wind power, biomass power and solar power, are summarized in the article. The experiences and lessons of implementation of these price policies are analyzed. It is concluded that reasonable price policy is quite effective for promoting re- newable power development. According to the requirement of China's renewable power development, the suggestions for improving renewable power pricing mechanism and price incentive policies are proposed.

Research on Optimal Configuration of Energy Storage in Wind-Solar Microgrid Considering Real-Time Electricity Price

Capacity allocation and energy management strategies for energy storage are critical to the safety and economical operation of microgrids.In this paper,an improved energymanagement strategy based on real-time electricity price combined with state of charge is proposed to optimize the economic operation of wind and solar microgrids,and the optimal allocation of energy storage capacity is carried out by using this strategy.Firstly,the structure and model of microgrid are analyzed,and the outputmodel of wind power,photovoltaic and energy storage is established.Then,considering the interactive power cost between the microgrid and the main grid and the charge-discharge penalty cost of energy storage,an optimization objective function is established,and an improved energy management strategy is proposed on this basis.Finally,a physicalmodel is built inMATLAB/Simulink for simulation verification,and the energy management strategy is compared and analyzed on sunny and rainy days.The initial configuration cost function of energy storage is added to optimize the allocation of energy storage capacity.The simulation results show that the improved energy management strategy can make the battery charge-discharge response to real-time electricity price and state of charge better than the traditional strategy on sunny or rainy days,reduce the interactive power cost between the microgrid system and the power grid.After analyzing the change of energy storage power with cost,we obtain the best energy storage capacity and energy storage power.

考虑市场影响的风电厂与储能运营商联合调度策略研究

本文基于拥有风力发电厂与电力储能设备的电力运营商视角,考虑运营商参与电力交易会对市场电价产生影响的基础上,通过动态规划,以利润最大化为目标,研究其最优联合调度策略。研究表明:在考虑充放电效率以及运营成本时,存在三个最优参考点将储能设备中的可用库存空间分为四个区域,进而对应四个不同的决策活动:将风电和从市场上购买的电力全部存入储能系统;将部分风电存入储能系统并将剩余部分销售到市场;售出全部风电不向储能设备中存入电量;将所有的风电和储能系统中的部分电量销售至电力市场。运营商可根据当前时刻风力发电量和储能设备中的电量与最优参考点之间的大小关系,得到相应的最优电力调度策略及其交易量。此外,本文研究发现随着市场影响强度的增大,运营商的利润随之减小,因此运营商应在其市场影响强度与最优电力交易量之间做好权衡。本研究对运营商的电力调度具有重要的指导意义和实际应用价值。

国有大型油气企业新能源发电项目经济评价探讨

国有大型油气企业基于减排降碳和可持续健康发展考量,积极探索新能源发电业务,投资项目经济评价方法和参数,成为影响新能源发电业务投资决策和高质量发展的决定性因素。基于经济评价基本原理,根据新能源发电项目技术经济特征,构建新能源发电项目经济评价方法和参数体系。折现现金流法仍然是新能源发电项目经济评价的主要方法,内部收益率和平准化度电成本是衡量项目盈利能力的重要指标。不同类型新能源发电项目经济评价方法具有较高的一致性,但应在投资构成、成本费用估算、收入与税金估算等方面体现差异,重点在营业收入估算中体现项目真正价值。在规制性配置储能要求以及储能收益政策有待落实的情况下,新能源发电项目效益有待提高,建议现阶段适当降低投资回报要求,尤其是出于市场拓展和协同发展目的的战略性新能源发电项目。项目电价和有效利用小时数对新能源发电项目的影响至关重要,应视情况合理选取参数。风光气电融合项目应分业务估算成本。国有大型油气企业应积极开展宏观配套政策和商业模式创新研究,以支撑新能源发电业务的高质量发展。

基于主从博弈的多虚拟电厂动态定价与优化调度

在“双碳”背景下,分布式可再生能源以及储能、需求响应等灵活性资源快速发展,虚拟电厂通过控制技术将分布式资源高效整合,提高了分布式能源发电效益。随着社会资本进入电力市场,不同虚拟电厂将会属于不同的投资商,形成多主体博弈格局,根据投资商投资偏好,虚拟电厂将由不同灵活性的资源构成。为兼顾虚拟电厂运营商和虚拟电厂利益,文章构建了运营商和多虚拟电厂双层主从博弈模型,考虑上层定价与下层出力的相互影响,研究运营商动态价格制定和虚拟电厂优化运行调度问题。下层以各虚拟电厂运行成本最小为目标,分别建立含有电储能、需求响应和氢储能的多虚拟电厂优化调度模型;上层以运营商利润最大为目标,结合下层出力计划进行虚拟电厂购售电价动态制定。采用粒子群算法迭代求解博弈模型,通过算例分析,该模型能够兼顾多主体利益,有效提高运营商收益并降低虚拟电厂运行成本。

市场是否挤出了信任:一个来自实验经济学的考察

市场是否挤出了信任是社会科学共同关注的一个基础性问题。本文运用信息不对称的经验品模型模拟了“有市场”环境,同时运用组内设计和数据平移创造性地设计了一个博弈结构完全相同的模型来刻画“无市场”环境,并设置了七个实验局分别剥离了市场中的语言描述、消费者选择权、商家定价权三个要素,从而全面对比了“有市场”与“无市场”时信任水平的差异。实验结果表明:首先,市场能够有效提升信任水平,市场与信任可形成正反馈,这进一步凸显了市场在资源配置中的决定性作用;其次,消费者选择权与商家定价权所发挥的作用并不对称,其中消费者选择权是关键因素,保护消费者权益对于构建一个良性有效率的市场尤为重要;再次,声誉是消费者选择权促进信任水平提升的重要渠道。本文加深了我们对市场自由竞争本质以及市场机制运行的理解,并为我国的市场化改革提供了重要启示:要尊重市场运行规律、强化竞争政策基础地位、保障消费者权益。

中国式现代化视角下中国铁矿石类大宗商品对外贸易定价权研究

改革开放以来中国经济发展迅速,逐渐步入工业化中后期阶段,对各类大宗商品的需求与日俱增。在国际市场,中国作为全球大宗商品重要的贸易国与消费国,缺乏对大宗商品定价权的影响力,受大宗商品国际价格波动影响较大,在国际大宗商品贸易中较为被动。基于国际铁矿石贸易市场的基本现状,以铁矿石为切入点,分析了当前中国在国际大宗商品的定价权,根据国内大宗商品进口贸易情况,探讨了在国际贸易中中国大宗商品定价权缺失的原因,并提出了相关对策建议。

四川省气电容量成本回收机制研究

四川省发展气电是实现“双碳”目标,提升电力调峰调频、确保安全稳定供电的重大举措。2022年四川省出台气电上网两部制电价政策指导意见,明确气电容量电价按一定合理收益回收固定投资成本,电量电价与气价实施联动调整。通过梳理国家及部分省份的气电两部制电价政策,调查分析四川气电的成本构成,研究对气电投资成本回收机制并测算容量电价,提出了容量电价测算原则、方法以及疏导路径的相关建议。研究结果表明:①因地制宜出台气电价格政策有利于推动气电产业健康可持续发展;②实施气电两部制电价有利于通过容量电价回收固定成本且取得合理收益,有利于促进四川气电产业有序健康可持续发展,并通过相对较低的电量电价实现与电力市场逐步接轨,增强市场竞争力;③容量电价按照“谁受益、谁承担”和“合理分摊、动态调整”原则进行疏导;④气电容量电价标准按资本金内部收益率8%对应取值,F机组容量电价标准可为28元/(kW·月),并且容量电费由该省内大工业、一般工商业用户疏导分摊。