PG&E resumes Diablo Canyon relicensing

PG&E submitted its application to renew the operating licences for the two pressurised water reactors in 2009, but withdrew it in 2018 after the California Public Utilities Commission (CPUC) approved a joint proposal from the company together with labour and leading environmental organisations to close the plant at the end of its current licences, in 2024 for unit 1 and 2025 for unit 2. At that time, it was thought that the plant's output would no longer be required as California focused on an energy policy centred on efficiency, renewables and storage - but grid reliability issues have prompted a rethink on the plant's early closure.

"Recently, the State of California has revisited its current and projected energy needs, including the role of DCPP (Diablo Canyon Power Plant) in the State's energy future," PG&E said in its request to the NRC, and the CPUC's 2018 decision approving the retirement of the plant has now been reversed. "Based on the recent change of energy policy by the State of California to support its critical energy needs, PG&E is requesting that the NRC staff resume its review of the LRA (licence renewal application) for DCPP units 1 and 2 to ensure an adequate energy supply for California."

US nuclear regulations stipulate that licence renewal applications should be filed at least five years before the expiration of a plant's existing licence. Should the NRC not grant PG&E's request to resume its review of the previous application, instead requiring it to submit a new application, the company asked the regulator for its assurance of "timely renewal protection".

It requested a decision from the regulator "as soon as possible to support the next steps for PG&E in extending the operation of DCPP units 1 and 2 beyond the expiration of the current operating licenses to serve California's urgent energy needs and help ensure grid reliability" in the letter, which was signed by PG&E's Senior Vice President and Chief Nuclear Officer Paula Gerfen.

Senate Bill 846, which was signed on 2 September, will allow the units to operate for up to five years beyond 2025 to act as a bridging technology to ensure a reliable energy system and reduce greenhouse gas emissions until additional renewable and zero-carbon energy sources come online. It also includes a USD1.4 billion loan to PG&E.