PG&E Announces Closure of California’s Last Nuclear Power Plant

One of the most famous, but aging, nuclear power plants in the U.S. will soon see its end

Diablo Canyon Nuclear Power Plant
A view of the Diablo Canyon Nuclear Power Plant, with two reactors. dirtsailor2003 via

After 2025, the Golden State may no longer make nuclear energy. This week, Pacific Gas & Electric Co. announced that the state's only remaining nuclear power plant, the Diablo Canyon Power Plant in San Luis Obispo County will be retired when it's operating licenses expire, Ivan Penn and Samantha Masunaga report for the Los Angeles Times

The plant's history was fraught with controversy from the beginning, when a seismic fault, the Hosgri fault, was discovered only three miles offshore from the plant's location in 1971. 

Concerns about the plant's vulnerability to seismic activity intensified after disaster struck the Fukushima Daiichi Nuclear Power Plant in 2011. That nuclear crisis contributed in part to the decline of nuclear power in many countries, including the United States. Reduced electric demand and cheap natural gas prices helped send the nuclear power industry into a crises, Diane Cardwell reports for the New York Times

State energy policies ensured that "there's just not going to be enough need to have to run your nuclear power plant," Anthony Earley, PG&E's chief executive told reporters. 

Currently, the Diablo Canyon plant produces about 2,160 megawatts of energy that can power about 1.7 million homes, Penn and Masunaga report. The energy is used in Central and Northern California.

The controversy surrounding the plant continues with this new announcement. Environmental groups have long protested Diablo Canyon. (But even that had controversy: Disagreements over the power plant led to the fracturing of the Sierra Club and the formation of Friends of the Earth, an anti-nuclear group.) Now the decision to shutter the plant has been met with mixed reactions

"Nuclear power plants are the only current source of low-carbon electricity that can be built just about anywhere," writes John Timmer for Ars Technica. "But the Fukushima disaster has raised some significant questions about the wisdom of putting plants just anywhere."

The worry is that the low-carbon nuclear energy will be replaced with greenhouse-gas-producing forms of energy generation, as it has been in other states. To assuage some of that concern, PG&E proposes to make up the difference with renewable energy, including solar and wind, as well as improvements in energy efficiency and storage. The company worked with environmental groups including Friends of the Earth to craft the proposal, Penn and Masunaga report.

The plan also has just under a decade to play out, time that will be needed. 

"Giant baseload nuclear power plants like Diablo Canyon cannot easily be taken offline, or ramped up and down, as system needs change,” says Ralph Cavanagh, who co-directs the energy program at the Natural Resources Defense Council and acted as lead negotiator on the Diablo Canyon agreement, reports the New York Times. "This worsening problem is forcing the California grid operator to shut down low-cost renewable generation that could otherwise be used productively."

Exactly how the plan will unfold is still subject to changing regulations, economic concerns and factors such as potential spikes in natural gas prices, reports Brad Plumer for Vox. The move comes against a background where the fate of nuclear energy is still under debate.

But for better or for worse, at least for the time being, California appears to be leaving the nuclear energy arena. 

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