Federal Regulator Completes Environmental Review of Diablo Canyon Extended Operations

Diablo Canyon Power Plant has reached another milestone in its relicensing. 

The U.S. Nuclear Regulatory Commission has released its final Supplemental Environmental Impact Statement on the power plant’s continued operation.

The commission’s review found that “there is no environmental reason for energy-planning decisionmakers to prevent the plant from operating for another 20 years.”

The statement is the culmination of nearly two years of detailed technical reviews and audits of Diablo Canyon’s Environmental Report, which the power plant submitted to the commission in November 2023. The commission released a draft Supplemental Environmental Impact Statement in October 2024 for public comment. The commission also held two public meetings on the statement in November 2024. The final statement considered public comments.

The commission also consulted with other federal agencies, including the U.S. Fish and Wildlife Service and the National Marine Fisheries Service.

The statement comes two weeks after the commission released its Safety Evaluation Report. That report found that Diablo Canyon is safe to operate for 20 more years.

Diablo Canyon is California’s largest clean energy producer. It produces nearly 20% of the state’s clean power. It also meets 10% of the state’s electric demand and serves 4 million customers.

The plant was set to retire in 2025, but the state of California directed Diablo Canyon to stay open through 2030 for electric grid reliability.

Customers will see big financial benefits from keeping Diablo Canyon open. Without the power plant, California energy producers would have to purchase expensive replacement power. Families’ energy bills would rise by $3.2 billion through 2030. That would average about $540 million a year.

California also needs a reliable grid while it moves to 100% clean energy.

With its Safety Evaluation Report and final Supplemental Environmental Impact Statement, the commission has completed its review of Diablo Canyon’s license renewal application.

Still needed are approvals from the California Coastal Commission and the Regional Water Board.

The U.S. Nuclear Regulatory Commission will make a final decision on the license renewal application once the coastal commission and water board issue their decisions.