Economic Criteria for Planning Transmission Investment in Restructured Electricity Markets

From an economic perspective, a common criterion for assessing the merits of a transmission investment is its impacts on social welfare. The underlying assumption in using this criterion is that side payments may be used to distribute the social gains among all market players. In reality, however, since the impacts of an electricity transmission project on different players may vary, such side payments are rather difficult to implement. This paper focuses on different economic criteria that should be considered when planning electricity transmission investments. We propose an electricity transmission investment assessment methodology that is capable of evaluating the economic impacts on the various effected stakeholders and account for strategic responses that could enhance or impede the investment's objectives. We formulate transmission planning as an optimization problem under alternative conflicting objectives and investigate the policy implications of divergent expansion plans resulting from the planner's level of anticipation of strategic responses. We find that optimal transmission expansion plans may be very sensitive to supply and demand parameters. We also show that the transmission investments have significant distributional impact, creating acute conflicts of interests among market participants. We use a 32-bus representation of the main Chilean grid to illustrate our results.     

China’s electricity transmission and distribution tariff mechanism based on sustainable development

In order to guarantee the rapid sustainable development of the social economy, the power grid will make large investments in the construction of smart grids, the renewable energy network, the construction of long-distance transmission grid channels as well as the technology and service innovation of the power grid. According to the electricity transmission and distribution tariff accounting mechanism of costs and benefits, the power grid investment needs to be recycled by the transmission and distribution tariff. However, at present, the low electricity transmission and distribution tariff in China, which is based on the difference between the electricity sales price and the average purchase price, cannot guarantee the return of investment and the sustainable development of the power grid. Based on the current situation of China’s power grid construction and electricity transmission and distribution tariff, this paper proposes that the new investments in the power grid can be divided into technical innovation investments, environmentally friendly investments, service promotion investments and other kinds of investments, according to their functions. Then, four electricity transmission and distribution tariff and power grid investment linkage models are built and example analysis undertaken, respectively, which are the timely linkage model, static linkage model, ladder linkage model, in which the electricity tariff space changes by a fixed absolute value annually and ladder linkage model in which the electricity tariff space changes by a fixed proportion value annually. The results reveal that the ladder linkage model in which the electricity tariff space changes by a fixed absolute value annually can guarantee relatively smooth changes in the electricity tariff, and is suitable for the actual situation of China’s power market. The transmission and distribution electricity tariff and power grid investment linkage models based on sustainable development built in this paper are beneficial for promoting the reforms of the electricity transmission and distribution tariff in China and guiding the establishment of a scientific electricity tariff mechanism.     

提高导线运行允许温度若干问题的探讨

用电量的迅速增长引发了线路输送容量扩容的问题，这在经济发达地区的迎峰度夏输电运行工作中尤为突出。提高现有送电线路导线运行允许温度可使线路扩容问题得到一定程度的解决，该方案因简单易行，投资小而受到供电部门的关注。提高导线运行允许温度后，对导线弧垂、接续金具发热和导线机械强度的影响进行了试验研究、理论分析和实际观测，可为线路的安全运行提供参考。     

电力市场环境下合理回报输电容量投资的方法

全球电力工业正进行一场解除管制的改革,而现有输电定价方法对输电容量投资,仍沿用传统的按既定回报率的简单回收,文章指出这种回报在市场环境下不尽合理,并提出基于输电容量市场供需回报思想,介绍了实现该思想的网嵌入边际成本输电定价新方法,解析推导说明了该方法下电网的弹性收支平衡机制及其在体现输电容量投资回报和引导电网优化发展上的合理性,并用数字算例作了论证。     

碳纤维复合芯（ACCC）导线在输电线路中的应用

随着电力需求的迅速增加,提高输电线路的输送容量、减少对环境的影响是电力企业不断努力的方向。通过在高压线路中应用碳纤维复合芯（ACCC）导线技术进行了初步探讨。     

基于线路有功潮流使用度和可靠性贡献的输电固定成本分配方法

计算输电线路固定成本时将其分成容量使用固定成本和可靠性固定成本2部分,容量使用固定成本根据交易对线路有功潮流的使用度来分配;可靠性固定成本根据线路的可靠性贡献来分配,并计及了线路潮流变化、停运概率和停运时间的影响。该方法适用于联营和双边交易共存的电力市场,既满足电路定律,又给出了良好的经济信号。仿真算例验证了方法的有效性。     

Does economic growth promote electric power consumption? Implications for electricity conservation,expansive, and security policies

The purpose of this study is to determine the relationship between electric power consumption per capita (kWh) and real GDP per capita (PEN, constant 2007 prices), in Peru, during the period 1971–2014. The four theoretical hypotheses behind this relationship are the growth hypothesis –electricity consumption explains economic growth–, the conservation hypothesis –economic growth explains electricity consumption–, the feedback hypothesis –mutually affecting explanation between electricity consumption and economic growth–, and neutrality hypothesis –electricity consumption does not explain economic growth and vice versa–. Empirically, we initially conclude that the conservation hypothesis can be confirmed using the Granger Causality test, after estimating the dynamic impacts of the long-run equilibrium and short-run models. We highlight the inelastic behavior of electric power consumption per capita with regard to real GDP per capita. These results have implications for electricity conservation, expansive and security policies. We also discussed investments in electricity generation, transmission and distribution from renewable energy sources such as hydro, wind and solar. These eco-sustainable energies also called green and clean energies, are necessary for the sustainability of the electric power demand and the level of national electrification.     

基于功率分布的节点电价修正方法

对于开放的电力市场,输电网损耗的经济信号对引导电力市场参与者合理配置资源有着不容忽视的影响。在仅考虑输电损耗的前提下,发电厂的售电收入应与用户端的支出相等,在此基础上,基于功率分布方法提出了节点电价修正新方法。功率分布方法可给出电源提供的功率分量在线路传输功率、线路损耗和负荷中分布的解析表达式。模型可考虑电源位置、电源供电路径和电源输电损耗对节点电价的影响。最后以IEEE30节点系统算例验证了所述方法的可行性。     

当量电价体系及相关制度设计:(七) 阻塞管理的当量电价法

输电阻塞本质上是输电容量的不足。传统的短期边际成本输电定价方法使网公司的收入严重不足，相应电价也不能给出充分反映输电容量不足的信号，而输电当量电价却有独特优势。在输电当量电价模型基础上，采用用户上报支付意愿的方法，建立了直接阻塞管理模型。该模型还可以在仅仅用电价调控阻塞无能为力的情况下合理削减负荷，同时又可获得充足而又合理的电网扩建资金，有利于输电网的投资扩容，从根本上缓解阻塞问题；通过用户上报支付意愿，引导用户参与阻塞管理。算例中将输电当量电价法与传统短期边际成本方法做了比较，并讨论了与支付意愿有关的市场特性。结果表明，该方法更合理、更有效。     

Combined natural gas and electricity network pricing

The introduction of competition to electricity generation and commercialization has been the main focus of many restructuring experiences around the world. The open access to the transmission network and a fair regulated tariff have been the keystones for the development of the electricity market. Parallel to the electricity industry, the natural gas business has great interaction with the electricity market in terms of fuel consumption and energy conversion. Given that the transmission and distribution monopolistic activities are very similar to the natural gas transportation through pipelines, economic regulation related to the natural gas network should be coherent with the transmission counterpart. This paper shows the application of the main wheeling charge methods, such as MW/gas-mile, invested related asset cost (IRAC) and Aumman-Shapley allocation, to both transmission and gas network. Stead-state equations are developed to adequate the various pricing methods. Some examples clarify the results, in terms of investments for thermal generation plants and end consumers, when combined pricing methods are used for transmission and gas networks. The paper also shows that the synergies between gas and electricity industry should be adequately considered, otherwise wrong economic signals are sent to the market players.     

Estimation method for dynamic line rating potential and economic benefits

The determination of economic benefits of increasing transmission capability by dynamic line ratings is a multifaceted task. In addition, there are many parties concerned within the complex electricity markets. This paper suggests a method for the evaluation of economic feasibility and benefits, as well as for the minimum potential assessment of employing dynamic line ratings. The suggested deterministic method considers very conservative assumptions in order not to compromise the power system reliability, even though the method is intended for the power system planning and not for the operation purposes. The method is applicable for congested transmission connections between electricity market price areas and it is demonstrated with a distinct case study of congestion on the power transmission from Sweden to Finland. Despite the very conservative assumptions used in the ampacity calculation to be on the safe side, the method can clearly point out the motivation to consider the implementation of dynamic line ratings on congested transmission connections in order to relieve bottlenecks and provide benefits for the society.     

基于模型校核的输电线路载流量限额动态评估

急剧增长的用电需求和高比例可再生能源发电并网给现有输电系统带来了较大压力.动态增容技术是提升线路输送能力的经济有效的手段,但受数据采集精度、计算模型参数时变特征等影响,现有动态增容系统在实际应用中仍存在计算精度不足、可靠性偏低等问题.为降低数据采集质量和载流量模型精度对动态增容技术可靠性的影响,提出并构建了一种基于实时闭环校核的载流量及弧垂计算模型修正方法.结合数值天气预报,进一步提出了一种输电线路载流量限额动态评估方案,在动态校核载流量和弧垂计算模型的基础上,实现对实时和预测载流量限额的滚动修正.最后,通过实际工程案例验证了模型校核方法和载流量限额动态评估方案的正确性和可行性.     

Multistage expansion planning of generation and interconnections with sustainable energy development criteria: A multiobjective model

A novel multiobjective, multiarea and multistage model to long-term expansion planning of integrated generation and transmission corridors incorporating sustainable energy developing is presented in this paper. The proposed MESEDES model is a “bottom-up” energy model which considers the electricity generation/transmission value-chain, i.e., power generation alternatives including renewables, nuclear and traditional thermal generation along with transmission corridors. The model decides the optimal location and timing of the electricity generation/transmission abroad the multistage planning horizon. The proposed model considers three objectives belonging to sustainable energy development criteria such as: (a) the minimization of investments and operation costs of power generation, transmission corridors, energy efficiency (demand side management (DSM) programs) considering CO2 capture technologies; (b) minimization of Life-Cycle Greenhouse Gas Emissions (GHG); and (c) maximization of the diversification of electricity generation mix. The proposed model consider aspects of the carbon abatement policy under the CDM - Clean Development Mechanism or European Union Greenhouse Gas Emission Trading Scheme. A case study is used to illustrate the proposed framework.     

Economic evaluation of independent power producers viewed from total generating costs of electric power systems

In Japan, electric power utilities purchase electricity from independent power producers (IPPs) through competitive bidding; the IPP evaluation is based on the avoided costs of corresponding generators of utilities. In this evaluation, however, nonpricing factors such as power flow constraints in the electric power system cannot be considered. In this paper, we propose a new approach to evaluate economic impacts of IPPs, the IPP electricity being priced on the basis of total generating costs of the electric power utilities. Such a price to purchase the electricity of IPPs is referred to as the “break‐even cost.” The main results are summarized as follows: 1) Break‐even cost depends on not only the power flow constraints in the system, but also various IPP factors such as generating pattern, location, and capacity, 2) Break‐even cost for the base‐type IPP is higher than the avoided cost of corresponding utility generators, because IPPs located on demand sides can reduce the transmission power loss in the electric power system, 3) Break‐even cost is affected by available capacity of utility generators, especially for the peak‐type IPP generating only during peak demand periods. © 2000 Scripta Technica, Electr Eng Jpn, 133(2): 20–30, 2000     

海洋采油平台直流配电网瞬时负载的适应性评估

在海洋石油工程中,电动机是主要的电气负载,其起动过程可能会产生瞬时冲击,影响直流配电网的系统性能。文中基于降阶解析的思想,对此特殊场景下瞬时负载的影响开展研究。首先在一定条件下简化系统动态微分代数方程,推导直流母线电压的近似解析表达式;然后研究瞬时有功负载对海洋采油平台直流母线电压的影响;最后在PSCAD/EMTDC中搭建四端柔性直流配电网模型并设置不同的瞬时负载进行仿真,分析不同瞬时负载情况下的直流母线电压,验证文中所提解析表达式的正确性。结果证明,文中的解析表达式可以有效反映海洋采油平台直流配电网对瞬时负载的适应性。     

基于输电当量电价的直接阻塞管理

输电网阻塞本质上是反映线路传输容量之不足。基于传统的短期边际成本方法所给出的阻塞电价信号不足以反映输电线路容量之不足。针对这一问题，文章在输电当量电价模型的基础上，引入“支付意愿”概念，建立了阻塞管理模型。该模型能在利用电价调控阻塞无能为力的情况下合理地削减负荷，同时又承袭了输电当量电价充分回报容量投资，充分而又合理地积累电网扩建资金的特性，从而比较好地解决了阻塞管理问题。此外，还允许用户参与阻塞管理，还增进了市场效率和公正性。算例结果表明，该方法能有效地解决输电网的阻塞问题。     

基于上流有限元法对高压直流输电线路下合成电场的研究

高压直流输电线路产生的地面合成电场和离子流密度是设计和建设输电线路时应考虑的2个主要电磁环境指标。为预测高压直流输电线路的电磁环境问题,基于上流有限元法开发了相应的分析预测软件。同轴圆柱结构的解析解和实验线路的测量数据验证了该方法的有效性。最后,分析了双极线路情况下线路高度、极间距和表面状况以及单极情况下风速对地面合成场强和离子流密度的影响,这些结果对设计高压直流输电线路具有一定的指导意义。     

Market-Based Coordination of Transmission and Generation Capacity Planning

We propose an ISO model for coordinating transmission expansion planning with competitive generation capacity planning in electricity markets. The purpose of the model is a holistic simulation of generation and transmission capacity expansion in the market environment. The solution represents an iterative process for simulating the interactions among GENCOs, TRANSCOs, and the ISO, which might be terminated by the ISO based on a pre-specified stopping criterion. The proposed model adopts a joint energy and transmission auction market and a capacity mechanism. The joint auction market enables competition to occur among generation and transmission resources. The capacity mechanism offers incentives for market participant investments that reflect the locational values of additional capacity. Transmission capacity expansion decisions are made by merchant transmission lines that recover their capacity investments through transmission marginal pricing and capacity payments. Transmission network security is reflected in the proposed competitive resource planning model. The examples illustrate a coordinated planning of generation and transmission in restructured power systems.     

容量电价机制对发电商竞价行为的激励

容量电价是调控电源投资和建设的一种宏观手段，还会对市场成员的竞价行为及电力市场交易产生影响。该文从激励的角度分析容量电价对市场成员竞价行为的影响，并利用基于报价中标概率信念函数的电力市场模拟方法，通过建立考虑容量电价因素的发电商个体新决策模型，定量研究和比较了国内两种不同容量电价补偿机制对发电商竞价行为和市场均衡状态的影响。理论分析和算例表明，按照中标容量支付容量电价，会抑制发电商的报价投机行为，使市场均衡价格较低。     

An Effective Transmission Network Expansion Cost Allocation Based on Game Theory

The expansion of transmission systems impacts many entities in the market environment. Each entity may fare better or worse as a result of congestion relief in the presence of new investments. Negatively affected firms exert their influence to prevent the expansion from taking place. The opposition of these firms and the lack of appropriate incentives results in insufficient investments in transmission assets. The network is being frequently used at its maximum limits, leading to economic inefficiencies and reduced reliability. Hence, there is a need for effective incentive schemes for network expansion. In this paper, we propose a game theory-based scheme for the allocation of transmission expansion costs among market entities. The allocation takes into account both the physical and economic impacts of the new transmission assets and the influence of each firm on the expansion decision. This is the first scheme designed to give all market participants explicit incentives to support the expansion. The application of the allocation solution to the Garver six-bus system is presented to illustrate the capabilities of the proposed method