12 MW Hydro operating in Stillwater, MT — NorthWestern Energy (NWMT)
12 MW
Nameplate Capacity
2
Generators
units
Conventional Hydroelectric
Technology
1925
Operating Since
Coordinates
45.2257, -109.7625
County
Stillwater, MT
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | NorthWestern Energy (MT Hydro) | — | — |
| Owner(s) | NorthWestern Energy (MT Hydro) | — | — |
| Status | Operating | — | — |
The Mystic hydroelectric plant is located in Stillwater County, Montana. The plant has a total capacity of 12 MW across two generators, and it began operating in 1925. The primary fuel source is water. NorthWestern Energy (MT Hydro) operates the facility, which is within the NorthWestern Energy (NWMT) balancing authority and the Western Electricity Coordinating Council (WECC) NERC region.
In the most recent year with available data, Mystic generated 53,734 MWh, achieving a capacity factor of 50.9%. The plant is ranked 18th out of 23 power plants in Montana, and 616th out of 1464 plants nationally. Financial data indicates an installed cost of $2,187.77 per kW.
Generated from EIA, GEM, and public data sources
NERC Region
WECC
Balancing Authority
NorthWestern Energy (NWMT)
Grid Voltage
50 kV
Regulatory Status
RE
Entity Type
Investor-Owned Utility
Sector
Electric Utility
2.4K MWh
Latest Month
53.7K MWh
Annual Generation
50.9%
Capacity Factor
$2,236/kW
Installed Cost
$12.2/MWh
Operating Cost
NorthWestern Corporation
Reporting Utility
Cumulative Installed Cost
Per-Unit Cost Trends
This plant is outside organized wholesale electricity markets (ISOs/RTOs). Nodal pricing data is not available.
Last updated 2026-03-26
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