Prairie Du Sac
Hydro power plant · Sauk County, Wisconsin
Nameplate capacity
33 MW
Rank in Wisconsin
#75
of 278 plants
In service since
1938
March 1938
Details
- Primary fuel
- Hydro
- Technology
- Conventional Hydroelectric
- Operator
- Wisconsin Power & Light Co
- County
- Sauk County
- Generating units
- 8
- Share of state capacity
- 0.17%
- Rank among hydro plants in Wisconsin
- #5 of 61
- EIA plant code
- 4056
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| 3 | Conventional Hydroelectric | 4.8 MW | — | 2020 | Operating |
| 4 | Conventional Hydroelectric | 4.8 MW | — | 2022 | Operating |
| 2 | Conventional Hydroelectric | 4.3 MW | — | 2015 | Operating |
| 5 | Conventional Hydroelectric | 4.0 MW | — | 1938 | Operating |
| 6 | Conventional Hydroelectric | 4.0 MW | — | 1938 | Operating |
| 7 | Conventional Hydroelectric | 4.0 MW | — | 1940 | Operating |
| 8 | Conventional Hydroelectric | 4.0 MW | — | 1940 | Operating |
| 1 | Conventional Hydroelectric | 3.5 MW | 29 MW | 2015 | 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 Wisconsin
| Cornell | Hydro | 35 MW |
| Holcombe | Hydro | 34 MW |
| MMSD Jones Island Wastewater | Natural gas | 31 MW |
| Montfort Wind Energy Center | Wind | 30 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 33 MW solar plant and a 33 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 Wisconsin power plants · What Wisconsin actually generates