California Regulators Grant Diablo Canyon Nuclear Plant 5-Year Extension

Aerial view of the Diablo Canyon Nuclear Power Plant, which sits on the edge of the Pacific Ocean at Avila Beach in San Luis Obispo County, Calif., on March 17, 2011. Mark Ralston/AFP via Getty Images

In two recent decisions, state and federal energy regulators have approved a plan by Pacific Gas and Electric to continue running California’s last working nuclear power plant beyond 2025—which will boost energy supplies for the state as it transitions to renewable energy.

The federal Nuclear Regulatory Commission elected to review PG&E’s license renewal application Dec. 19, allowing the utility to continue operating Diablo Canyon’s two remaining reactors, which would have expired in 2024 and 2025.

The decision allows the commission time to evaluate the utility’s application, which typically takes about 22 months, according to PG&E.

If granted, the renewal would authorize the plant to continue operating for up to 20 years, according to PG&E.

Additionally, the California Public Utilities Commission voted to allow the nuclear plant to continue operating until 2030. The extension gives the state extra time to fully transition to renewable energy sources, officials said.

“PG&E remains committed to complying with energy policies to ensure the state has the option to keep [Diablo Canyon Power Plant] online past 2025 to ensure electricity reliability as California continues toward its clean energy future,” said Maureen Zawalick, the power plant’s vice president, in a Dec. 19 statement. “We are grateful for the opportunity to continue providing homes and businesses across California with safe, clean, and affordable power.”

The Diablo Canyon Power Plant employs about 1,300 in San Luis Obispo County, situated between San Francisco and Los Angeles on California’s Central Coast.

The plant provides about 17 percent of California’s zero-carbon electricity supply and about 9 percent of the state’s electricity.

The past week’s regulatory decisions angered some environmental groups and, in an opposite sentiment, spurred reaction from at least one congressman who said he was in favor of keeping the plant open longer.

“[Five] years isn’t enough,” said Rep. Doug LaMalfa (R-California), in a Dec. 15 post on X, formerly Twitter. “Diablo Canyon is a critical part of California’s energy infrastructure, supplying almost 10 [percent] of our state’s power. If Dems in Sacramento are going to decimate the oil and natural gas industries, they can’t also take away our sole nuclear power plant.”

The plant’s extension was opposed by several environmental groups that claimed keeping it operating could cost up to $45 billion and prolong the risk of failure at the aging plant.

“This ill-conceived decision will further escalate financial strain on California ratepayers and extend the threat of a catastrophe at Diablo Canyon,” said Ken Cook, president of the Environmental Working Group and a Bay Area resident, said in a statement Dec. 14.

In August, a California judge rejected a lawsuit filed by Friends of the Earth, which sought to derail the plant’s extended operations. In the ruling, the judge dismissed the complaint, agreeing with PG&E that the environmental group was asking the court to “hinder or interfere” with state regulatory oversight of the plant, according to the Associated Press.

And in October, the Nuclear Regulatory Commission rejected a request from environmental groups to immediately shutter one of the two reactors, AP reported.

Fearing political backlash last year over the threat of another summer of rolling blackouts, Gov. Gavin Newsom signed Senate Bill 846 into law, which allowed PG&E to continue operations beyond 2025.

California’s extreme summer temperatures and wildfires have strained the state’s power grid in the past few years, causing rolling blackouts and government pleas to conserve energy.

Fearing more electricity shortages as green-energy infrastructure lagged, state lawmakers approved a plan in 2022 to temporarily allow the Diablo Canyon plant to continue operating until 2030, pending regulatory approvals. They also agreed to spend $1.4 billion to keep the plant running.