Holter — Plant Summary
- EIA Plant ID
- 2186
- Capacity
- 54.6 MW
- Primary Fuel
- Hydro
- Technology
- Conventional Hydroelectric
- Status
- Operating
- Location
- Cascade, MT
- Operating Since
- 1918
- Generators
- 4
- Operator
- NorthWestern Energy (MT Hydro)
- Parent Company
- NorthWestern Energy Group
- Annual Generation
- 265,780 MWh
- Capacity Factor
- 55.4%
- Balancing Authority
- NorthWestern Energy (NWMT)
- ISO/RTO
- —
- NERC Region
- WECC
Holter
OperatingHydro
Ranked #13 of 23 Hydro plants in MT#284 of 1454 nationally
54.6 MW Hydro operating in Cascade, MT — NorthWestern Energy (NWMT)
EIAGEMWD
54.6 MW
Nameplate Capacity
4
Generators
units
Conventional Hydroelectric
Technology
1918
Operating Since
Location
Coordinates
46.9915, -112.0047
County
Cascade, MT
Nearby Plants
- HauserHydro26.8 MW · 26.6 km
- Great Divide Solar, LLCSolar3 MW · 27.7 km
Ownership & Operator
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | NorthWestern Energy (MT Hydro) | NorthWestern Energy | — |
| Owner(s) | NorthWestern Energy (MT Hydro) | NorthWestern Energy Group | — |
| Status | Operating | operating | — |
Ownership Chain
About
The Holter plant, located in Cascade County, Montana, is a 54.6 MW conventional hydroelectric facility. It began operating in 1918 and consists of 4 generators. The plant's primary fuel source is water (WAT). It is owned by NorthWestern Energy Group and operated by NorthWestern Energy (MT Hydro). Holter ranks as the 13th largest power plant in Montana out of 23, and 288th nationally out of 1464.
In the most recent year with available data, Holter generated 265,780 MWh of electricity, achieving a capacity factor of 55.4%. The plant operates within the NorthWestern Energy (NWMT) balancing authority and the Western Electricity Coordinating Council (WECC) NERC region. Financial data indicates an installed cost of $409,724.28 per kW.
Generated from EIA, GEM, and public data sources
Engineering & Generators
Grid Context
NERC Region
WECC
Balancing Authority
NorthWestern Energy (NWMT)
Grid Voltage
100 kV
Regulatory Status
RE
Entity Type
Investor-Owned Utility
Sector
Electric Utility
Generation
19.4K MWh
Latest Month
265.8K MWh
Annual Generation
55.4%
Capacity Factor
Jan 2022 – Dec 2024
Financial DataBeta
Source: FERC Form 1HIGH
$763/kW
Installed Cost
$4.2/MWh
Operating Cost
NorthWestern Corporation
Reporting Utility
Cumulative Installed Cost
Per-Unit Cost Trends
Pricing & Market Data
This plant is outside organized wholesale electricity markets (ISOs/RTOs). Nodal pricing data is not available.
News & Articles (10)Beta
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Last updated 2026-03-26
View all 10 articles