San Diego County’s nuclear power plant, San Onofre, was closed more than 10 years ago. But the Diablo Canyon plant is still open and cranking out 18,000 gigawatts a year.
The contract for the Diablo Canyon nuclear plant was set to expire by the end of next year. But a bill passed two years ago by the legislature has kept it open an additional five years, closing one reactor in 2029 and the other in 2030.
The plant, near San Luis Obispo, generates nearly 10% of California’s total energy. But critics say it’s actually giving the state too much energy, especially in the spring when hydropower production is at its highest.
Energy economist Richard McCann works with the consulting firm M. Cubed. He said in 2023 California generated enough hydropower to match the power we already got from the nuclear plant.
“That combination made it so that we had a lot of excess power in the system. It’s not that there was excess solar power. It was excess power. And the bigger culprit for that excess power is Diablo Canyon, which was supposed to be retired,” McCann said.
McCann said when the state has too much power, it can either try to sell it to neighboring states, often at rock bottom prices, or it has to just dump the energy, which then goes to waste.
Solar power has become a plentiful clean energy source that the state may have underestimated when it chose to extend Diablo Canyon.
Some people who run California’s statewide power grid say nuclear is clean power. It generates no greenhouse emissions. But it does create nuclear waste and it has to run 24-7, making it very inflexible.
“With the lack of flexibility, and the growth of flexible resources that we have coming on to our system, I just don’t know if there’s going to be value in retaining those resources,” said Brian Murray, director of real time operation with the California Independent System Operator (ISO).
Pacific Gas & Electric (PG&E), the investor-owned utility that runs Diablo Canyon, describes the plant as well run and a source of clean energy. But McCann said nuclear power from Diablo Canyon is expensive. PG&E is applying to raise its rates in order to keep the plant open.
That cost will affect San Diego customers of SDG&E also, and it’s something lawmakers didn’t anticipate when they voted to extend the life of the nuclear plant.
PG&E couldn’t be reached for comment for this story.
