The Gates 500 kV Dynamic Reactive Support Project, now known as the Orchard Substation, was awarded to LS Power Grid California, LLC in 2020 through a competitive solicitation conducted by CAISO for its 2018-2019 Transmission Planning Process. This reliability driven project will provide critical reliability for the CAISO grid in California’s San Joaquin Valley by mitigating high voltages and thermal overloads that would otherwise result from retirement of the Diablo Canyon nuclear power plant. The project is located in Fresno County, California with a planned in service date of 2025.
The Project includes two ±424 MVAR static synchronous compensator (STATCOM) blocks interconnecting to the 500 kV bus at the existing Gates substation. The STATCOMs will be connected to the Gates 500 kV bus via two 500/97.5 kV transformers located inside the new Orchard substation and two short 500 kV overhead transmission lines to be constructed by PG&E.
Construction began in 2023 at the Orchard Substation with testing and energization of the new project facilities planned for completion in late 2024 or early 2025.