Investment in transmission is recognized as essential to power system decarbonization, and at the same time it has been established that proactive grid planning can help mitigate market failures in electricity markets such as market power. In this paper, we bring these ideas together by exploring the extent to which transmission planning can proactively and cost-effectively reduce carbon emissions, while accounting for inefficient generation investment and operating incentives caused by the coexistence of inconsistent carbon regulation regimes within the same regional power market. Using a bilevel transmission planning model, we compare the economic efficiency of two proactive grid planning schemes to reduce carbon emissions (in comparison with a no-transmission-expansion benchmark) under three policy cases: no carbon policy; multiple sub-jurisdictions in a region with inconsistent policies (here called “heterogeneous subregional policies”); or consistent system-wide carbon policies. The two proactive planning schemes are a traditional co-optimization-based planning scheme based on minimizing in-market costs (i.e., system costs excluding costs of externalities), and a sustainable planning scheme where the grid planner accounts for system-wide carbon emission damage costs even though generation companies may be subject to no or heterogeneous subregional carbon pricing policies. In the bilevel model, the transmission planner at the upper level decides on locations and capacity of grid enhancements, whereas the generators, operators, and load-serving entities make generation expansion and dispatch decisions at the lower level. Based on the insights from both a simplified 3-node case study and a realistic 300-bus case study for the power system of western North America, we find that traditional co-optimization-based grid planning can yield some economically efficient CO2 emission reductions, especially in the absence of a system-wide carbon pricing policy and Renewable Portfolio Standard (RPS) policies. But when taking RPS into consideration together with a cleaner resource mix, traditional grid planning may provide little or no emission benefits due to the regional heterogeneity of policies. On the other hand, accounting for emissions in a sustainable proactive planning framework can provide additional emission reduction benefits at a reasonable cost when a sufficiently high value of carbon damage cost is considered.

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主动的输电规划能否经济高效地减少碳排放？北美西部案例研究

输电投资被认为对电力系统脱碳至关重要，同时已经确定，主动电网规划有助于缓解电力市场的市场失灵，例如市场支配力。在本文中，我们通过探索输电规划在多大程度上可以主动且经济高效地减少碳排放，同时考虑由于同一区域电力市场内不一致的碳监管制度共存而导致的低效发电投资和运营激励措施，将这些想法汇集在一起。使用双层输电规划模型，我们比较了三种政策情况下两种主动电网规划方案减少碳排放的经济效率（与无输电扩建基准相比）：无碳政策;政策不一致的区域内的多个次级管辖区（此处称为“异质次区域政策”）;或一致的全系统碳政策。这两种主动规划方案是一种传统的基于协同优化的规划方案，基于最小化市场成本（即排除外部性成本的系统成本），另一种是可持续规划方案，其中电网规划者考虑整个系统的碳排放损害成本，即使发电公司可能不受或受制于次区域碳定价政策。在双层模型中，上层的输电规划者决定电网增强的位置和容量，而发电商、运营商和负载服务实体在下层做出发电扩建和调度决策。 基于北美西部电力系统的简化 3 节点案例研究和现实的 300 路公交车案例研究的见解，我们发现传统的基于协同优化的电网规划可以产生一些经济高效的 CO2 减排，尤其是在没有全系统碳定价政策和可再生能源组合标准 （RPS） 政策的情况下。但是，当将 RPS 与更清洁的资源组合一起考虑时，由于政策的区域异质性，传统的电网规划可能提供很少或根本没有排放效益。另一方面，当考虑到足够高的碳损害成本时，在可持续的主动规划框架中考虑排放可以以合理的成本提供额外的减排效益。