American Nuclear Society files FERC comments on Diablo Canyon’s early closure

November 16, 2020, 10:20AMPress Releases

La Grange Park, IL – The American Nuclear Society (ANS) has submitted comments to the Federal Energy Regulatory Commission (FERC) in favor of reconsidering the shortsighted decision to shutter prematurely California’s largest clean energy resource, Diablo Canyon nuclear power plant.

ANS filed the comments on Nov. 12 in favor of an Oct. 26 complaint by Californians for Green Nuclear Power against the regulatory approvals of the 2016 decision by Pacific Gas & Electric Co. to permanently shutter Diablo Canyon Units 1 and 2 in November 2024 and August 2025, respectively. The complaint (Docket No. EL21-13-000) asked FERC to investigate whether the decision shuttering Diablo Canyon violates grid reliability standards. ANS agrees with the complaint that FERC ought to consider fully the negative consequences and reliability risks posed by a premature retirement of Diablo Canyon.

“Closing California’s only remaining operating nuclear power facility will threaten more rolling blackouts for the Golden State as Diablo Canyon reliably supplies approximately 10 percent of in-state power,” wrote ANS Executive Director/CEO Craig Piercy and President Mary Lou Dunzik-Gougar in the comment to FERC.

“Along with further weakening California’s fragile power grid, the premature closure of Diablo Canyon will deprive California of its largest carbon-free energy resource and worsen the state’s growing dependency on natural gas imports,” ANS commented.

As pointed out by the complaint, approximately 60% of California’s dispatchable in-state bulk power supplies already come from natural gas-fired generation, with 95% of this greenhouse gas-emitting fossil fuel pumped in from out of state. About 25% of California’s total electricity needs are currently met by imports as in-state renewables are too weak and inconsistent to reliably meet demand.

During the August heatwave, power grid operator – the California Independent System Operator – ordered rolling blackouts across the state to avoid a power supply shortage of 4,400 megawatts that would have left approximately 3.3 million in the dark without air conditioning. “The rolling blackouts would have been far worse without Diablo Canyon’s 2,240 megawatts of safe, reliable, fuel-secured and zero-emissions baseload power,” wrote ANS.

“California’s vulnerability to blackouts and pipeline disruptions – including those caused by wildfires and earthquakes – demonstrates the necessity in keeping Diablo Canyon’s clean baseload power beyond 2025 for the safety and prosperity of 40 million Californians,” continued ANS. “In wake of any blackout or extreme event, Diablo Canyon’s fuel-secured, reliable and safe baseload power will surely be needed to restore power in California.”

“We prefer the Diablo we know over the costs, risks, and uncertainty of a power grid without it,” concluded Piercy and Dunzik-Gougar.

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Established in 1954, ANS is an international professional organization of engineers and scientists devoted to the peaceful applications of nuclear science and technology. Its more than 9,500 members represent government, academia, research laboratories, medical facilities, and private industry. ANS’s mission is to advance, foster, and spur the development and application of nuclear science, engineering, and technology to benefit society.

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