OCI, LG Seal Deal for 120-MW Alamo City Battery Project

• OCI Energy teams with LG Energy Solution Vertech and CPS Energy to build the 120-MW/480-MWh Alamo City BESS in Bexar County, boosting ERCOT’s long-duration storage.

Renewable-energy developer OCI Energy LLC has chosen LG Energy Solution Vertech as the technology vendor for the Alamo City Battery Energy Storage System, a 120-MW/480-MWh lithium-ion project slated for southeastern Bexar County, Texas. The partners signed a memorandum of understanding this week, clearing the way for detailed engineering and procurement to begin this summer.

Under the agreement, OCI will develop, finance, build and own the four-hour facility while municipal utility CPS Energy takes the storage capacity under a long-term contract. Construction is set to kick off in early 2025, with commercial operation targeted for late 2026—a schedule that would lift CPS Energy’s contracted battery fleet to 520 MW just as older gas units in its “Vision 2027” transition plan begin to retire.

Four-hour batteries remain rare in the ERCOT market, where most projects discharge for one or two hours. The longer duration will let CPS shift midday solar surpluses into the evening peak, provide ancillary grid services and bolster resilience during extreme weather events that have strained Texas’ power system in recent years.

LG Energy Solution Vertech will supply fully integrated containerised systems—lithium-ion modules, inverters and a proprietary energy-management platform—designed to operate in Texas’ punishing summer heat. The company said its high-density chemistry will allow OCI to minimise land use while meeting ERCOT’s stringent performance standards.

The Alamo City project extends OCI’s decade-long collaboration with CPS Energy that began with some of Texas’ first utility-scale solar farms. Formerly known as OCI Solar Power, the developer now manages a national portfolio of solar-plus-storage projects and has pledged $250,000 for local workforce training tied to the new battery plant. With permitting already under way, OCI says the build will create roughly 150 construction jobs and a dozen permanent operations roles—rooting more clean-energy know-how in San Antonio’s fast-growing tech corridor.