Old 300 Storage Center

Old 300 Storage Center is a 250 MW / 500 MWh, two-hour standalone battery energy storage system located at approximately 102 JC Wicks Road, Needville, Texas, in Fort Bend County. The facility uses 166 Tesla Megapack 2XL units and reached commercial operations on August 5, 2026. It is fully integrated into the ERCOT grid and independently operated from the co-located 430 MW Old 300 Solar project. The facility provides grid-stability resources and helps address ERCOT's tight supply-demand periods.

Reporting month describes the inventory. Retrieval and map preparation describe processing; an OSM edit does not establish an in-service date.

EIA-923 reports gross generation and net grid exchange for storage plants. Gross generation is shown as a discharge proxy; it is not a cycle count or conventional capacity factor.

EIA-860 lists generator 8681 with this operating date.