Bat Cave
Bat Cave is a 100 MW battery storage project in Mason County, Texas, operated by Engie North America. EIA-860M lists 1 generating unit here, inside ERCOT. Its unit entered service in 2021.
As of 2026-07 (inventory dated 2026-07-31) · EIA-860M Preliminary Monthly Electric Generator Inventory · eia.gov/…/july_generator2026.xlsx · eia.gov/…/eia860m
- Nameplate capacity
- 100 MW
- 100 MW net summer
- Generating units
- 1
- In service
- 2021
- EIA plant ID
- 64312
Where it is
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- County
- Mason County, Texas
- Coordinates
- 30.7377, -99.2318
- Balancing authority
- ERCO
- Sector
- IPP Non-CHP
Units, technology and status
- Operator of record
- Engie North America
- Primary energy source
- Battery
- Technologies
- Batteries
- Status
- Operating
Bat Cave: FAQ
- Where is Bat Cave?
- In Mason County, Texas (TX). The map on this page is placed at the coordinates EIA files for the plant, which locate the site rather than any individual unit.
- How big is Bat Cave?
- 100 MW of nameplate capacity across 1 unit, as of the EIA-860M release for 2026-07.
- Who owns Bat Cave?
- EIA-860M names Engie North America as the reporting entity. That is the operator of record on the survey, which is not always the ultimate owner.
- Is this the same as Bat Cave LLC?
- Probably, but EIA-860M does not say. The survey records a plant name and a reporting entity — Engie North America here — not the project company that holds the asset. Project companies are commonly registered as an LLC carrying the plant's name, so a search for "Bat Cave LLC" usually means this site. This page shows only what EIA files, and does not assert a corporate structure it cannot see.
- Is Bat Cave still running?
- EIA-860M files it as "Operating" for 2026-07. Statuses change monthly, and this page follows the monthly release.