A nonprofit nuclear power advocacy group in California has called on the Federal Energy Regulatory Commission to review California regulators' decision to approve the retirement of Pacific Gas and Electric Co.'s 2.24-GW Diablo Canyon nuclear plant in 2025.
The Californians for Green Nuclear Power's complaint asked FERC to launch an investigation into whether the California Public Utilities Commission, California ISO, California State Water Resources Control Board, and California State Lands Commission violated mandatory reliability standards when they approved Diablo Canyon's retirement "without first properly analyzing the adverse bulk electric system and adverse bulk natural gas system consequences."
The complaint also alleged that the North American Electric Reliability Corp., which crafts and enforces the reliability standards for the bulk power system, and the Western Electricity Coordinating Council, a regional compliance authority of NERC, "failed to conduct proper oversight or enforce NERC's reliability standards to prevent reliability standards violations caused by removing [Diablo Canyon's] 2,240 MW from the California electric grid."
A major concern for the group is that most of the state's natural gas-fired generation is vulnerable to earthquakes and slow aseismic creep that can damage pipelines. And this is a problem because about 60% of California's dispatchable generation is fueled by natural gas, and 95% of that gas is imported from other states.
The complaint also noted that Diablo Canyon is California's largest generator and provides about 10% of the power produced in the state. And the power produced ty that facility is carbon-free, reliable, and fuel secure since it operates independently of the state's aging and vulnerable gas transmission and storage system.
In addition, the complaint lamented California's already high level of dependence on power imported from other states, which contributed to the August 2020 blackouts in the state. The group contended that those blackouts were not an isolated incident but a consequence of "much larger systemic reliability challenges that will only be made worse by the voluntary closure of [Diablo Canyon]."
The group also said the use of certain tools to maintain grid reliability, such as preemptive power shutoffs in the case of wildfires and adverse weather events, could present additional reliability challenges because they are likely to be used more frequently going forward.
As such, "there are significant reliability benefits to both the bulk electrical and bulk natural gas systems in California associated with the continued safe operation beyond 2025 of PG&E's [Diablo Canyon] as well as the re-commissioning of the San Onofre Nuclear Generating Station that ceased operations in 2012," the group said in the complaint.
Two units at San Onofre were retired after replacement components did not perform as expected and repairs were deemed too costly to be economic. Dismantlement of structures at San Onofre began this year.
In 2016 PG&E proposed retiring Diablo Canyon in conjunction with the expiration of the units' Nuclear Regulatory Commission licenses, on Nov. 24, 2024, for unit 1, and Aug. 26, 2025, for unit 2. The CPUC approved the retirement plan in 2018. (FERC docket EL21-13)
Jasmin Melvin is a reporter with S&P Global Platts. S&P Global Market Intelligence and S&P Global Platts are owned by S&P Global Inc.