US utility Pacific Gas and Electric Company (PG&E) has commissioned a 182.5MW lithium-ion battery energy storage system (BESS) at its Moss Landing electric substation in the US.
Using Tesla Megapacks, the project in Monterey County, California known as the Elkhorn Battery, was fully energised and certified for market participation by the California Independent System Operator (CAISO) on 7 April after final testing.
The system will help integrate renewable energy sources, such as solar, and enhance the overall reliability of California’s energy supply by delivering grid services such as peak shifting.
The energy storage system includes 256 Megapack battery units; each unit houses lithium-ion batteries and power conversion equipment in a single cabinet.
Transformers and switchgears were installed with the Megapacks to connect the BESS to the 115kv electric transmission system.
The BESS has the capacity to store and dispatch up to 730MWh to the electrical grid at a maximum rate of 182.5MW for up to four hours during periods of high demand.
Timeline to commissioning
The BESS was approved by the California Public Utilities Commission (CPUC) in November 2018 and by the Monterey County Planning commission in February 2020.
Site construction began in July 2020, with the system designed, constructed, and maintained by PG&E and Tesla, and owned and operated by PG&E.
PG&E had aimed to have the system energised and fully operational in the second quarter of last year.
The Elkhorn Battery system was named for its location on the mouth of the Elkhorn Slough on Monterey Bay.
The system represents one of the largest utility-owned, lithium-ion battery energy storage systems in the world.
In January, power generation firm Vistra confirmed it plans to further expand its Moss Landing Energy Storage Facility in California.
The company entered into a 15-year resource adequacy agreement with PG&E for a new 350MW/1.4GWh battery system.
However, in February shorted lithium-ion batteries and subsequent smoke were believed to have triggered the shutting down of the world’s biggest energy storage system, suggested Vistra Energy.
Leaked water is believed to have caused the batteries to short and prompted the early detection safety system to activate in the 100MW Phase II building at the Moss Landing Energy Storage Facility in Monterey County, California, US late on 13 February.
A growing trend
PG&E now has contracts for battery energy storage systems totalling more than 3,330MW of capacity being deployed throughout California through 2024.
Of the 955.5MW (of the 3,330MW under contract) of new battery storage capacity connected to California’s electric grid, the projects include:
- 5MW PG&E Elkhorn Battery in Monterey County, commissioned 2022
- 200MW Diablo Storage System in Contra Costa County, commissioned 2022
- 60MW Coso Battery Storage located in Inyo County, commissioned 2022
- 400MW Vistra Moss Landing Battery Energy Storage Facility in Monterey County, commissioned 2021
- 63MW NextEra Blythe system in Riverside County, commissioned 2021
- 50MW Gateway system in San Diego County, commissioned 2021
- PG&E anticipates an additional 1,400-plus MW of storage capacity (of the 3,330MW under contract) to come online in 2022 and 2023.
