A leading provider of grid-connected energy storage solutions announced the start of commercial operation for a project in Imperial County, California. LS Energy Solutions (LS-ES) on September 4 said its Big Rock 200-MW/400-MWh site, which was developed in partnership with Gore Street Energy Storage Fund (GSF), is the company’s largest energy storage installation to date and its first for the California Independent System Operator (CAISO) grid.
LS-ES on Thursday said the project is now providing resource adequacy and ancillary services for CAISO.
“We are thrilled to see the Big Rock site in full commercial operation and providing storage services for CAISO,” said Curt Feldman, vice president at LS Energy Solutions. “As California’s grid faces challenges from data center growth, wildfires, and the need to meet carbon reduction goals, utility-scale storage like Big Rock is more critical than ever. Gore Street Energy Storage Fund has been an excellent partner for this project, and we look forward to working with them on future CAISO projects.”
The Big Rock site includes 137 LS-ES AiON-ESS containers storing energy for two-hour durations. LS-ES and GSF currently operate the site at 100 MW of deliverability to supply 400 MWh to CAISO, meeting the four-hour discharge stipulation of a 12-year resource adequacy contract.
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LS-ES, in addition to supplying AiON-ESS containers, also is supporting the site with operational services that include preventative and capacity maintenance, an extended warranty, and system remote monitoring for the life of the project.
GSF acquired the Big Rock site in February 2023 from clean energy developer Avantus. It is the developer’s first project for CAISO. Big Rock joins other energy storage investments by GSF in Texas, Ireland, Great Britain, and Germany, with a total operational portfolio of 753.4 MW/924.1 MWh of energy storage assets.
“We are pleased to see Big Rock delivering the full suite of storage services to CAISO, including operation under the 12-year Resource Adequacy contract we have secured,” said Alicja Kowalewska-Montfor, technical principal at Gore Street Capital. “This marks our first project in CAISO, one of North America’s leading grid operators. Our 200-MW/400-MWh site, supported by LS Energy Solutions, will play a vital role in supporting CAISO in building a more flexible grid for Californians, and we look forward to supporting the operator for years to come.”
—Darrell Proctor is a senior editor for POWER.
