Phasing Out Nuclear Power in California

Diablo Canyon Nuclear Power Plant. Image courtesy Nuclear Regulatory Commission and PG&E.

Nuclear power and the future of California’s electricity grid made the news last week with the announcement that the California Public Utilities Commission unanimously approved closing the state’s last remaining operating nuclear power plant, Diablo Canyon, located near San Luis Obispo. In June 2016, PG&E announced that it had reached a historic agreement with labor and environmental organizations to phase out nuclear operations at Diablo Canyon by 2025, when the power plant’s licenses expire. PG&E’s proposal to cease operations included replacing the loss of energy generation with investments in energy efficiency and carbon-free electricity, including the achievement of 55 percent renewable energy in its electricity portfolio by 2030. SPUR wrote about this promising idea in our 2016 report Fossil-Free Bay Area.

Diablo Canyon, which began operations in 1985, currently supplies about 18 percent of the Bay Area’s utility-provided electricity and 9 percent of California’s energy portfolio. Its pending closure means the state (and PG&E) will have to meet ambitious climate targets with even more efficiency investment and renewable sources than originally envisioned. While some are concerned, PG&E believes it can be done.

New nuclear power plants have been banned in California since the mid 1970s on the premise that new facilities should not be sited until the federal government could establish a safe place for disposal of spent fuel. That has still not happened. With no offsite storage options available, most decommissioned nuclear power plants in the United States have waste decaying in place and are constantly monitored. The decommissioning process can take up to 60 years and will cost more than $8 billion in California alone.

California may have decided to eschew nuclear energy on its clean energy pathway, but this decision is not without controversy in other contexts. Some climate scientists and energy analysts believe the world cannot achieve the global warming limits established by the Paris climate agreement in 2015 without a significant replacement of coal power with nuclear. But nuclear power has significant unresolved challenges, including nuclear waste and the risk of catastrophic meltdowns that occur with generational regularity (most recently in 2011, when a meltdown of the Fukushima Daiichi plant in Japan was triggered by a tsunami).

In addition, nuclear power isn’t carbon-free. Lifecycle nuclear power emissions are lower than coal on a per-kilowatt-hour basis, but they are twice as high as solar photovoltaic and six times greater than onshore wind. In addition, the falling cost of renewable energy, coupled with advancing climate policy, makes these types of investments more attractive and less risky than nuclear for utilities and their customers.

Still, a handful of nuclear power plants are expected to come online in the United States in the next five years, and more than 20 are under construction in China, as are dozens more around the world, including in Russia, India and South Korea. As these projects proceed (or don’t), California can move forward with its plan to add renewables paired with investments in efficiency and a smart grid — letting the nuclear debate go on elsewhere.

The closure proposal originally put forth by PG&E, environmental groups and labor included both a plan to replace Diablo Canyon’s electric power through energy efficiency programs and carbon-free sources and a plan to use ratepayer funding to help transition and retrain the plant’s workers. Last week’s announcement punts the decision about replacement sources to a separate proceeding in the future and also authorizes fewer resources for workers. While the Public Utilities Commission stated an intent to avoid any increases in greenhouse gases from the closure of Diablo Canyon in seven years, Californians will have to wait a little longer for confirmation that this will actually be the case.