CA SB846

Invalidates the Public Utilities Commission's 2018 approval of the Diablo Canyon powerplant retirement and requires the PUC to authorize extended operations until October 31, 2029 (Unit 1) and October 31, 2030 (Unit 2), conditioned on US Nuclear Regulatory Commission license renewal.

Establishes the Diablo Canyon Extension Fund with $600 million from the General Fund and authorizes up to $1.4 billion in Department of Water Resources loans to the powerplant operator for costs associated with extending operations, with strict conditions and oversight requirements.

Requires the PUC to authorize cost recovery through nonbypassable charges on all electrical customers, including volumetric payments of $6.50 per megawatthour and fixed annual payments of $50 million per unit, with market revenues and federal funds used first to repay the loan.

Sets October 31, 2030 as the final compliance date for the powerplant's once-through cooling system under the State Water Resources Control Board's policy and extends nuclear emergency funding provisions until 18 months after permanent plant closure.

Requires quarterly reliability assessments from the Energy Commission and PUC, cost-effectiveness comparisons by September 30, 2023, and continued funding and authority for the Independent Safety Committee for Diablo Canyon during extended operations.