Black Mesa BESS — Plant Summary
- EIA Plant ID
- 66326
- Capacity
- 40 MW
- Primary Fuel
- Battery Storage
- Technology
- Batteries
- Status
- Operating
- Location
- Elmore, ID
- Operating Since
- 2024
- Generators
- 1
- Operator
- Idaho Power Co
- Parent Company
- IDACORP
- Annual Generation
- -3,177 MWh
- Capacity Factor
- -1.1%
- Balancing Authority
- Idaho Power Company
- ISO/RTO
- —
- NERC Region
- WECC
Black Mesa BESS
OperatingBESS
Ranked #6 of 10 BESS plants in ID#422 of 837 nationally
40 MW BESS operating in Elmore, ID — Idaho Power Company
EIA
40 MW
Nameplate Capacity
1
Generators
unit
Batteries
Technology
2024
Operating Since
Location
Coordinates
42.9083, -115.1828
County
Elmore, ID
Nearby Plants
- Black Mesa Solar, LLCSolar40 MW · 1.2 km
- Bliss (ID)Hydro75 MW · 9.1 km
- High MesaWind40 MW · 11.8 km
Ownership & Operator
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Idaho Power Co | Idaho Power | — |
| Owner(s) | Idaho Power Co | IDACORP | — |
| Status | Operating | — | — |
Ownership Chain
About
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
Engineering & Generators
Grid Context
NERC Region
WECC
Balancing Authority
Idaho Power Company
Grid Voltage
138 kV
Regulatory Status
RE
Entity Type
Investor-Owned Utility
Sector
Electric Utility
Generation
−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.
Financial Data
No financial data available for this plant.
Pricing & Market Data
This plant is outside organized wholesale electricity markets (ISOs/RTOs). Nodal pricing data is not available.
News & Articles (4)Beta
Regulatory·permitting
Idaho Power Company; Notice of Intent To File License Application, Filing of Pre-Application Document, and Approving Use of the Traditional Licensing Process
Federal Register (FERC)·3 days ago
General
Idaho Power seeks regulatory approval of 100MW additional BESS after offtake agreement with Savion falls through
Idaho Power is seeking approval from the state regulator to deploy an additional 100MW of BESS to plug the gap left within its portfolio.
Energy-Storage.News·1 years ago
Grid·capacity addition
Construction begins on Idaho Power’s first energy storage project as it faces growing capacity shortfall
State regulators said “public convenience and necessity” require Idaho Power to acquire 120 MW of dispatchable energy storage.
Idaho Power (operator)
Utility Dive·3 years ago
General
Idaho Power begins work on state’s first utility-scale storage installation
Work began last week on Idaho's largest energy storage projects to date, with 80 MW of battery systems being constructed by Idaho Power at its Hemingway...
Daily Energy Insider·3 years ago
Last updated 2026-03-25
View all articles