The complaint: In its filing, CGNP claimed that CAISO, CPUC, CSWRCB, and CSLC violated federal reliability standards for the bulk power system “through the CPUC’s approval of the plan to close Diablo Canyon … without first properly analyzing the adverse bulk electric system and adverse bulk natural gas system consequences, in light of known California-specific hazards.”
In addition, the complaint charged that NERC and WECC “failed to conduct proper oversight or enforce NERC’s reliability standards that will be violated by removing [Diablo Canyon] from the California electric grid.”
One of CGNP’s major concerns involves the state’s natural gas transmission and storage system. According to the complaint, because some 60 percent of California’s dispatchable in-state bulk electric generation system is powered by natural gas, “the reliability of California’s bulk electrical system is tightly coupled to the reliability of California’s natural gas bulk transmission and storage system. … There are present reliability challenges to [the latter system] that are a consequence of its vulnerability to sudden earthquake motions and slow aseismic (without an earthquake) creep caused by the relative motion of Earth’s crustal plates in California.”
Background: Located near Avila Beach, Calif., Diablo Canyon houses two four-loop Westinghouse pressurized water reactors; Unit 1, a 1,138-MWe PWR, began commercial operation in May 1985, while the 1,151-MWe Unit 2 started providing power in March of the following year.
In June 2016, PG&E announced that it had reached an agreement with organized labor and environmental organizations to increase investment in energy efficiency and storage, as well as renewables, and to close Diablo Canyon upon the expiration of the reactors’ operating licenses—November 2024 for Unit 1 and August 2025 for Unit 2.
PG&E’s application to close the plant was approved by the CPUC in January 2018, and in March of that year the utility notified the Nuclear Regulatory Commission that it was withdrawing its 2009 application for license extension.
