100 MW BESS operating in Mason, TX — Electric Reliability Council of Texas, Inc.
100 MW
Nameplate Capacity
1
Generators
unit
Batteries
Technology
2021
Operating Since
Coordinates
30.7341, -99.2311
County
Mason, TX
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Engie North America | Engie North America | — |
| Owner(s) | Engie North America | ENGIE | — |
| Status | Operating | — | — |
Located in Mason County, Texas, the Bat Cave power plant is a 100 MW battery energy storage system (BESS) facility owned by ENGIE, a company based in France, and operated by Engie North America. The plant began operating in 2021 and utilizes lithium-ion batteries (LIB) as its storage chemistry. The facility has a total storage capacity of 110 MWh, providing a duration of 1.1 hours at its full power output. The plant's primary fuel is electricity (MWH), which it uses to charge and discharge its batteries.
The Bat Cave plant operates within the Electric Reliability Council of Texas (ERCOT) balancing authority, placing it within the Texas Reliability Entity (TRE) NERC region. With a capacity of 100 MW, the plant is ranked as the 203rd largest power plant in Texas out of 224 facilities and 489th nationally out of 514. The plant consists of a single generator and has garnered some media attention, with 10 news articles published about it, covering topics such as industry trends, grid operations, and regulatory matters.
Generated from EIA, GEM, and public data sources
NERC Region
TRE
Balancing Authority
Electric Reliability Council of Texas, Inc.
Grid Voltage
138 kV
Regulatory Status
NR
Entity Type
Independent Power Producer
Sector
IPP Non-CHP
−857 MWh
Net Charging
-21.7K MWh
Annual Net Energy
-2.5%
Capacity Factor
Positive values indicate net discharge (generation exceeds station load). Negative values indicate net charging. Pure battery storage plants are typically net negative due to round-trip efficiency losses.
No financial data available for this plant.
Point of Interconnection
Nearest Substation
Fort Mason Substation · 138 kV
Substation Distance
0 km
Operator
Lower Colorado River Authority
Coord Source
OSM spatial
Market Position
ISO/RTO Market
ERCOT
LMP Node
BATCAVE_RN
Pricing Hub
HB_SOUTH
Secondary Zone
LZ_SOUTH
Location Type
Resource Node
Node Source
Curated node match
Last updated 2026-03-26
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