Diablo Canyon Enters Full Extended Operations

Like the dedicated colleague who couldn’t quit working, Diablo Canyon Power Plant isn’t going to retire anytime soon. 

On Wednesday (Aug. 27), Diablo Canyon’s Unit 2 officially began extended operations — one day after it was set to shut down. Unit 1 began extended operations in November 2024. 

Together, the units generate electricity for 4 million Californians. 

In 2016, with a decline in electric customers and state prioritization of solar and wind energy, PG&E agreed with environmental and labor groups to retire Unit 1 in November 2024 and Unit 2 in August 2025. State regulators approved the agreement in 2018. 

But after statewide rotating outages during a heat wave in 2020 and further demand projections in 2022, California lawmakers directed the San Luis Obispo County power plant to keep running through 2030. Their goal? Help grid reliability and support the state’s clean energy goals. 

“We’re proud to answer the call from state leaders to preserve Diablo Canyon’s safe, reliable and clean energy,” said Diablo Canyon Senior Vice President and Chief Nuclear Officer Paula Gerfen. “Diablo Canyon is critical to powering California’s clean energy future as the state continues to grow.” 

Diablo Canyon provides about 10% of California’s electricity and nearly 20% of its clean, carbon-free energy. 

Beyond being the state’s largest source of clean energy, Diablo Canyon runs 24/7. That makes it a steady power source as energy needs increase across the state. 

One big reason demand is rising: Data centers need lots of power, and the industry is growing. 

The California Energy Commission says demand from data centers could grow by four gigawatts in the next 10 years. The commission anticipates its next forecast will at least double. PG&E’s August 2025 estimate says demand could rise as much as 10 gigawatts. That equals the energy of five Diablo Canyons. 

Overall, the California Energy Commission expects peak electricity demand to grow by 21 gigawatts by 2040. That is equal to the energy of 10 Diablo Canyons. 

To give California policymakers more energy options as demand grows, Diablo Canyon has asked the U.S. Nuclear Regulatory Commission to renew its license to allow the plant to operate through 2045. That would give Californians more affordable clean energy while the state continues to build solar, wind and other renewables to meet its 2045 net-zero emissions goal. 

The license renewal process continues to progress. The Nuclear Regulatory Commission has completed its review and is awaiting approvals from the California Coastal Commission and the Regional Water Board. 

Southern California Edison recently found that running Diablo Canyon past 2030 would save its customers more than $1.4 billion by reducing the need for some new battery storage and solar power. 

Across the state, keeping Diablo Canyon open lowers electricity supply costs by up to 4%. 

There are environmental benefits, too. Keeping the plant running through 2030 avoids increasing the same amount of greenhouse-gas emissions as keeping 1.6 million gasoline-fueled cars off the road. 

In June 2025, the Nuclear Regulatory Commission said Diablo Canyon is safe and environmentally sound to operate for another 20 years. 

In San Luis Obispo County, Diablo Canyon is the largest private employer, with more than 1,300 coworkers. Every 18 months, during planned refueling outages, the plant hires another 1,100 workers for each reactor — up to 2,200 total, for a boost to the local economy. Polling shows more than 80% of local residents support Diablo Canyon’s operations. 

The plant also has a strong safety record. In 2024, the Nuclear Regulatory Commission once again ranked Diablo Canyon as one of the top-performing nuclear plants in the country. Year after year, the commission has ranked Diablo Canyon in its highest performance category for safety among more than 90 reactors across the country. 

Diablo Canyon looks forward to continuing to work with stakeholders, including customer and environmental advocates, regulators, lawmakers and policymakers, and welcomes their feedback through the transparent and open license renewal process.