The Diablo Canyon Power Plant Operation Assessment report addresses a requirement in Senate Bill 846 (Dodd, Chapter 239, Statutes of 2022) for the California Energy Commission, in coordination with the California Public Utilities Commission and the California Independent System Operator, to publish an assessment of the operation of the Diablo Canyon Power Plant, on or before July 1, 2023, and on July 1 of each year thereafter until 2031. The assessment includes outage information, power plant operational costs, average revenues from electricity sales, worker attrition, and the contribution of the power plant to resource adequacy requirements. This report serves as the July 2024 update.