California Considering Extending Life of Last Nuclear Plant 

AVILA BEACH, Calif. — As California braces for possible electricity shortages in the coming summer months, Gov. Gavin Newsom is considering delaying the planned decommissioning of the state’s last nuclear power plant.

The Diablo Canyon Power Plant was scheduled to have its twin reactors closed by its operator, Pacific Gas & Electric, in 2024 and 2025. The decision to retire the plant was made by PG&E in 2016 because California’s energy regulations give renewable energy priority over nuclear, making it uneconomical to keep in operation.

Those plans might change, however, as the California Independent System Operator warned its board of governors of forecasted shortfalls in electricity generation in a memo sent out on Wednesday. Newsom informed the editorial board of the Los Angeles Times last week the state would apply for a cut of the Department of Energy’s $6 billion Civil Nuclear Credit Program to avoid premature closures.

“The governor is in support [of] keeping all options on the table to ensure we have a reliable grid, especially as we head into a summer where California ISO expects [the state] could have more demand than supply during the kind of extreme events that California has experienced over the past two summers,” a spokesperson for Newsom said in an April 29 email. “This includes considering an extension to Diablo Canyon which continues to be an important resource as we transition to clean energy.”

Should Newsom decide to extend Diablo Canyon’s life, he would need PG&E to cooperate in applying for the federal credit program.

Diablo Canyon became California’s last nuclear power plant in 2013 when the San Onofre Nuclear Generating Station was closed. Environmental groups had long opposed the plant’s operation due to its proximity to seismic fault lines and its impact on fish larvae in the nearby Pacific Ocean.

In CAISO’s briefing on 2022 summer loads and resources assessment, the operator noted the probability of emergency energy alerts increased for 2022 because of a larger population of high loads in the forecast distribution. Despite this, CAISO said the number of hours of risk and the amount of load shed at risk will be significantly reduced in 2022 compared to last year.

Still, the dangers presented by heat waves and the state’s prolonged drought constitute a significant risk to California residents. Heat is the leading weather-related cause of death in the country despite most heat-related deaths being preventable through outreach and intervention, according to data published by the Environmental Protection Agency.

Although the International Brotherhood of Electrical Workers Local 1245 union initially signed on in support of PG&E and environmental groups’ joint proposal directing Diablo Canyon’s closure, union Business Manager Bob Dean issued a statement last week in support of keeping the plant operating past its planned decommissioning.

“On behalf of 28,000 members of IBEW 1245, we welcome, applaud and support the announcement by Gov. Gavin Newsom, in which he expressed interest in exploring federal funding to keep the Diablo Canyon Power Plant open,” Dean said in a written statement.

“Diablo Canyon is also a vital part of California’s clean energy future,” Dean continued. “As the largest generator of local, greenhouse-gas-free power in the state, Diablo Canyon provides much of the critical, local baseload power that California needs to meet its climate action goals.

“If Diablo Canyon were to close, the loss of the 2.2 [gigawatts] of clean power produced there would inevitably cause a significant increase in greenhouse gas emissions, and destabilize an already stressed grid.” 

California has until May 19 to submit an application for the Department of Energy nuclear credit program or else the state will miss out on the first award cycle. To date, Diablo Canyon is the single largest power station in the state, accounting for as much as 11% of California’s electrical generation and equivalent to 130% of its wind power and 42% of its solar power, according to the California Energy Commission.

Adam Stein, director of nuclear energy innovation at the Breakthrough Institute, told The Well News that if Diablo Canyon is shut down and replaced with other clean energy sources, as California currently plans to do, it would merely backfill the lost clean energy supply without progressing any further towards the state’s climate action goals.

Stein coined the term “treadmill decarbonization” to convey the method of replacing one clean energy source with another rather than using new clean energy to eliminate existing fossil fuel generation altogether. California would be “running in place” by prematurely decommissioning Diablo Canyon, he said.

“Nuclear is not considered part of the clean energy projects portfolio in California currently. It is excluded,” Stein told The Well News. “There’s a moratorium on building additional nuclear power [in the state]. They push very hard for adding wind and solar, and California has more solar than any other state. … They’ve made a lot of progress in that area, but they haven’t made as much as they could have in other areas.”

Although California currently exports solar energy in the middle of the day when it draws the most energy, the state has nearly reached the upper threshold for how much solar can be used during the daytime.  

Part of the state’s grid reliability issue comes from needing more energy outside of renewable resources, Stein said, and that’s why Diablo Canyon plays such a vital role in bolstering the energy supply.

By delaying the plant’s retirement until 2035, California could reduce its power sector carbon emissions by more than 10% from 2017 levels while reducing its reliance on natural gas, according to a joint assessment from researchers at Stanford University and the Massachusetts Institute of Technology. The researchers estimate California could save $2.6 billion in power system costs and ease brownouts by bolstering the power system’s reliability by temporarily delaying Diablo Canyon’s closure.

“Even assuming rapid and unconstrained buildout of renewable energy, the continued operation of Diablo Canyon would significantly reduce California’s use of natural gas for electricity production from 2025 to 2035 by approximately 10.2 [terawatt hours] per year,” the researchers wrote in the report.

“In doing so, Diablo Canyon would also reduce California carbon emissions by an average of seven [metric tons of] CO2 a year from 2025-2035, corresponding to an 11% reduction in CO2 from the electricity sector relative to 2017 levels.”

Reece can be reached at [email protected] and @ReeceNations