A proposed decision before the California Public Utilities Commission on Thursday calls for approving $723 million to keep the Diablo Canyon nuclear power plant in San Luis Obispo running to help bolster the stability of the state’s power grid. Since Diablo Canyon sends 2,240 megawatts of carbon-free electricity into California’s energy system, the costs associated with extending the plant’s operations through next year are spread across all ratepayers throughout the state — including those in the San Diego area. The $723 million price tag is split among customers of the state’s three investor-owned utilities. San Diego Gas & Electric officials estimate that a typical SDG&E residential customer will pay $1.90 more per month. That $1.90 increase would also apply to customers enrolled in the two community choice programs in the region — San Diego Community Power and the Clean Energy Alliance. The largest utility in the state, Pacific Gas & Electric, operates Diablo Canyon. PG&E had asked for $761 million but the public utilities commission in a 86-page proposed decision trimmed the request down to $723 million. The costs assigned to ratepayers cover the power plant’s operations from Sept. 1, 2023, through Dec. 31, 2025. How we got here Diablo Canyon was scheduled to shut down completely by 2025 but three years ago, Gov. Gavin Newsom made an about-face, fearing that closing the plant could jeopardize electric reliability and make the state grid vulnerable to power outages. By itself, Diablo accounts for 8.22% of in-state generation and 17% of California’s zero carbon electricity. At Newsom’s urging, lawmakers in Sacramento passed legislation in 2022 that extended the life of Unit 1 at Diablo Canyon through October 2029 and Unit 2 through 2030. The proposed decision calling for spending $723 million to extend the plant’s operations will go before a vote of the public utilities commission, known as the CPUC for short, on Thursday. Earlier this week, commissioners listened to oral arguments about the details of PG&E’s request. The Alliance for Nuclear Responsibility, a longtime critic of Diablo Canyon, said the extension is not needed, citing the growth of renewable resources and battery storage facilities on California’s energy grid. Since the 2022 legislation was enacted, “the panic over potential electricity shortages has diminished,” said John Geesman, an attorney for the group. He referred to an assessment by the CPUC and the California Energy Commission that 18,800 megawatts of new resources are predicted to come online by 2028. But Diablo’s supporters said battery storage systems are expensive and renewables are intermittent — that is, solar is not produced when the sun does not shine and wind generation drops to practically zero when the wind doesn’t blow. “The California power grid will be stressed in the future,” said Michael “Marty” Marinak of Californians for Green Nuclear Power. “All Californians are benefiting from Diablo’s safe, abundant, reliable, cost-effective and zero-emission power.” Despite the potential increase in bills, PG&E officials insist keeping Diablo Canyon running through 2030 amounts to a net plus for utility customers across the state. As PG&E breaks it down, all the cost and expense related to operating the plant are offset by what the utility estimates are $5.2 billion in electric generation revenue the plant produces, plus $5.9 billion for resource adequacy. To make sure there is enough energy capacity and reserves to maintain California’s electric system, all of the state’s “load serving entities” have to meet annual resource adequacy thresholds that are set by the CPUC. Related Articles Energy | New rate proposal calls for a smaller increase for SDG&E customers with natural gas Energy | New $42M battery storage facility set for Camp Pendleton Energy | SDG&E crews restore power after record-breaking winds blow through San Diego Energy | San Diego Supervisors sidestep new rules for battery projects amid fire concerns Energy | Santa Ana winds gusting up to 92 mph cause SDG&E to shut off power to 51,000 households “When that value is considered, Diablo Canyon provides a substantial net benefit to customers — whether an SDG&E, (community choice energy program) or other customer,” PG&E spokesperson Suzanne Hosn wrote in an email to the Union-Tribune. Affordability concerns But any increase in customer bills is far from welcome, especially with California utility rates on a steep and steady rise in recent years. An annual report released this summer by the CPUC predicts “electric rates are expected to continue increasing above inflation through 2027” for all three investor-owned utilities in the Golden State. The report anticipates the average electric rate for residential customers will grow 5.6% percent annually in SDG&E service territory, 6.8% for Southern California Edison and 10.8% in PG&E’s service territory.