Mousam River Solar
Solar power plant · York County, Maine
Nameplate capacity
20 MW
Rank in Maine
#45
of 274 plants
In service since
2025
November 2025
Details
- Primary fuel
- Solar
- Technology
- Solar Photovoltaic
- Operator
- Walden Renewables Development LLC
- County
- York County
- Generating units
- 1
- Share of state capacity
- 0.32%
- Rank among solar plants in Maine
- #5 of 175
- EIA plant code
- 69499
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| MRS1 | Solar Photovoltaic | 20 MW | 20 MW | 2025 | Operating |
Nameplate is the maximum rated output; summer capacity is what the unit can reliably deliver on a hot day, which is typically lower.
Similarly sized plants in Maine
| Twin Rivers Paper Co LLC | Other | 22 MW |
| Milo PV - BD Solar 1 LLC | Solar | 20 MW |
| Silver Maple | Wind | 20 MW |
| Spruce Mountain WInd | Wind | 20 MW |
About this data
From EIA’s inventory of operable generators, May 2026 release. Capacity is nameplate — the maximum rated output of the equipment, not what the plant actually generates over a year, which depends on how often it runs. A 20 MW solar plant and a 20 MW nuclear plant have the same entry here and produce very different amounts of electricity.
“In service since” is the earliest in-service date among the units still listed, so a site rebuilt around newer equipment can read as younger than the site itself. All Maine power plants · What Maine actually generates