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As the scale, speed, and implications of climate change come into focus, stakeholders in the electricity sector are finding it increasingly difficult to turn a blind eye. However, many have opted to attend to climate impacts in a piecemeal fashion, often merely responding to particular extreme events – or types of extreme events, such as coastal storms or floods – and failing to consider the larger phenomenon. This is true of the bulk power system (BPS) in regions overseen by Independent System Operators and Regional Transmission Organizations (collectively, ISO/RTOs), none of which have comprehensively assessed their systems’ vulnerabilities to climate change. Lacking such assessments, ISO/RTOs cannot plan for the impacts of climate change, and thereby ensure the continued reliability and resilience of the BPS.

The higher temperatures, more intense storms, and other weather extremes associated with climate change pose numerous threats to the BPS. These threats are summarized in a table in the appendix to this paper. As shown there, the impacts of climate change could force generating facilities to curtail output or shutdown, and lead to widespread transmission outages. These disruptions will be accompanied by other climate-driven phenomenon, including increases in electricity load and the height of load peaks, which will further strain facilities.

While the nature and extent of generation and transmission impairments will vary across the U.S. – due to differences in the nature and extent of climatic changes seen – no region will go unscathed. It is, therefore, vital that all ISO/RTOs begin planning now for a future in which climate change will feature. Otherwise, in the future, the BPS may be unable to deliver reliable electricity services at just and reasonable rates as required by the Federal Power Act.

This paper offers ISO/RTOs advice on how to plan for climate change and identifies resources and processes they could employ in the planning process. The regional variation in climate change impacts, as well as differences in generation and transmission resources, prevent formulation of a “one-size fits-all” approach to planning across ISO/RTO regions.


Environmental Law | Law