PG&E pitches 6.4 GWh of battery deals to help replace nuclear plant

Pacific Gas and Electric Co. has filed a request to add nine battery storage contracts totaling nearly 1,600 MW/6,400 MWh of capacity to come online by 2024, the PG&E Corp. operating arm announced Jan. 24.

The utility, known as PG&E, proposed the projects to the California Public Utilities Commission in response to the regulator's landmark order for load-serving entities to add 11.5 GW of clean energy resources between 2023 and 2026 to help offset the retirement of several aging natural gas-fired power plants and PG&E's Diablo Canyon nuclear power station, which is the Golden State's largest source of electricity.

PG&E proposed 15-year contracts for the projects, which are all four-hour lithium-ion battery resources. The projects will participate in California ISO wholesale markets, supplying energy and ancillary services like operating reserve to help support grid reliability, according to PG&E.

The utility now has contracts for more than 3,300 MW of battery storage through 2024. The 2,240-MW Diablo Canyon plant is scheduled to retire in two phases in 2024 and 2025.

The largest of the newly proposed systems is Vistra Corp.'s MOSS350 Energy Storage project, which would add another 350 MW of power storage capacity to the Moss Landing Energy Storage Facility, colocated with a natural gas plant in Monterey County, Calif. The contract calls for deliveries to begin in August 2023.

"These innovative battery energy storage systems are necessary to maintain electric grid reliability as increasing levels of intermittent renewable power are integrated into the electric grid," Vistra CEO Curt Morgan said in a Jan. 24 statement.

Vistra already has completed 400 MW/1,600 MWh for PG&E at the Moss Landing site under two separate contracts. However, 300 MW/1,200 MWh remains offline after lithium-ion batteries overheated in September 2021. Vistra expects to return that capacity to service in the near future, including 100 MW by the end of the first quarter and another 200 MW in the second quarter, the company said in a Jan. 21 update.

Roughly 7% of the facility's battery modules were damaged in the incident, which was not caused by the batteries themselves, according to the findings of an investigation shared by Vistra.

"Our priority was to conduct a safe and thorough investigation as quickly as possible, and implement any necessary corrective actions," Morgan said.

Vistra has a permit to ultimately expand the project to 1,500 MW/6,000 MWh.

PG&E also proposed three contracts with Terra-Gen LLC to start delivering energy in 2023. That includes 169 MW at the Edwards Sanborn Energy Storage project in Mojave, Calif. Terra-Gen also has a contract for 100 MW at its Beaumont Energy Storage project in Beaumont, Calif., and 80 MW at its Canyon Country Energy Storage project in Santa Clarita, Calif.

PG&E selected a subsidiary of NextEra Energy Inc. for two projects, including 275 MW at its Kola Energy Storage project in Tracy, Calif., and 125 MW at its Corby Energy Storage project in Vacaville, Calif., both anticipated online by June 2024.

The utility also chose: Arevon Energy Inc.'s 300-MW Nighthawk Storage facility in Poway, Calif.; Strata Clean Energy's 100-MW Inland Empire Energy Storage project in Rialto, Calif.; and the 99.7-MW Caballero Energy Storage project in Nipomo, Calif., being developed by a subsidiary of Origis Energy Ltd.