Rainbow (MT) — Plant Summary
- EIA Plant ID
- 2193
- Capacity
- 59 MW
- Primary Fuel
- Hydro
- Technology
- Conventional Hydroelectric
- Status
- Operating
- Location
- Cascade, MT
- Operating Since
- 2013
- Generators
- 1
- Operator
- NorthWestern Energy (MT Hydro)
- Parent Company
- NorthWestern Energy Group
- Annual Generation
- 328,967 MWh
- Capacity Factor
- 63.5%
- Balancing Authority
- NorthWestern Energy (NWMT)
- ISO/RTO
- —
- NERC Region
- WECC
Rainbow (MT)
OperatingHydro
Ranked #10 of 23 Hydro plants in MT#274 of 1454 nationally
59 MW Hydro operating in Cascade, MT — NorthWestern Energy (NWMT)
EIAGEMWD
59 MW
Nameplate Capacity
1
Generators
unit
Conventional Hydroelectric
Technology
2013
Operating Since
Location
Coordinates
47.5344, -111.2045
County
Cascade, MT
Nearby Plants
- CochraneHydro60.4 MW · 0.9 km
- Black Eagle Solar, LLCSolar3 MW · 3.7 km
- Black EagleHydro26.7 MW · 4.5 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
Rainbow Dam is a hydroelectric dam on the Missouri River, 29 feet (8.8 m) high and 1,055 feet (322 m) long, located six miles northeast of Great Falls in the U.S. state of Montana.
Read more on WikipediaThe Rainbow hydroelectric plant is located in Cascade County, Montana. It is owned by NorthWestern Energy Group and operated by NorthWestern Energy (MT Hydro). The plant has a total capacity of 59 MW from a single generator using conventional hydroelectric technology. Rainbow began operating in 2013 and is the 10th largest power plant in Montana out of 23, and the 278th largest in the United States out of 1464.
In the most recent year of data, Rainbow generated 328,967 MWh of electricity, achieving a capacity factor of 63.5%. The plant operates within the NorthWestern Energy (NWMT) balancing authority in the Western Electricity Coordinating Council (WECC) NERC region. Its primary fuel source is water (WAT).
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
23.2K MWh
Latest Month
329.0K MWh
Annual Generation
63.5%
Capacity Factor
Jan 2022 – Dec 2024
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 (10)Beta
Last updated 2026-03-26
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