Hemmingway BESS
Hemmingway BESS is a 166 MW battery storage project in Owyhee County, Idaho, operated by Idaho Power Co. EIA-860M lists 3 generating units here. Its units entered service between 2025 and 2026.
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
- 166 MW
- 166 MW net summer
- Generating units
- 3
- In service
- 2025–2026
- EIA plant ID
- 66325
Where it is
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- County
- Owyhee County, Idaho
- Coordinates
- 43.3515, -116.6621
- Balancing authority
- IPCO
- Sector
- Electric Utility
Units, technology and status
- Operator of record
- Idaho Power Co
- Primary energy source
- Battery
- Technologies
- Batteries
- Status
- Operating
Hemmingway BESS: FAQ
- Where is Hemmingway BESS?
- In Owyhee County, Idaho (ID). 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 Hemmingway BESS?
- 166 MW of nameplate capacity across 3 units, as of the EIA-860M release for 2026-07.
- Who owns Hemmingway BESS?
- EIA-860M names Idaho Power Co 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 Hemmingway BESS LLC?
- Probably, but EIA-860M does not say. The survey records a plant name and a reporting entity — Idaho Power Co 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 "Hemmingway BESS LLC" usually means this site. This page shows only what EIA files, and does not assert a corporate structure it cannot see.
- Is Hemmingway BESS still running?
- EIA-860M files it as "Operating" for 2026-07. Statuses change monthly, and this page follows the monthly release.