40 MW BESS operating in Elmore, ID — Idaho Power Company
40 MW
Nameplate Capacity
1
Generators
unit
Batteries
Technology
2024
Operating Since
Coordinates
42.9083, -115.1828
County
Elmore, ID
Nearby Plants
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Idaho Power Co | Idaho Power | — |
| Owner(s) | Idaho Power Co | IDACORP | — |
| Status | Operating | — | — |
Black Mesa BESS is a 40 MW battery energy storage system located in Elmore County, Idaho. The plant began operating in 2024 and has one generator. It is owned by IDACORP and operated by Idaho Power Company. The primary fuel type is electricity (MWH), and the storage technology consists of batteries. The battery system has a total storage capacity of 160 MWh, providing a duration of 4 hours. The battery chemistry is flow lithium battery (FLB).
The Black Mesa BESS operates within the Idaho Power Company balancing authority and the Western Electricity Coordinating Council (WECC) NERC region. It is ranked as the 6th largest of 10 battery storage plants in Idaho, and 635th out of 1205 nationally.
Generated from EIA, GEM, and public data sources
NERC Region
WECC
Balancing Authority
Idaho Power Company
Grid Voltage
138 kV
Regulatory Status
RE
Entity Type
Investor-Owned Utility
Sector
Electric Utility
−116 MWh
Net Charging
-3.2K MWh
Annual Net Energy
-1.1%
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.
This plant is outside organized wholesale electricity markets (ISOs/RTOs). Nodal pricing data is not available.
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