Marshalltown
Natural gas power plant · Marshall County, Iowa
Nameplate capacity
189 MW
Rank in Iowa
#45
of 305 plants
In service since
1978
June 1978
Details
- Primary fuel
- Natural gas
- Technology
- Natural Gas Fired Combustion Turbine
- Operator
- Interstate Power and Light Co
- County
- Marshall County
- Generating units
- 3
- Share of state capacity
- 0.76%
- Rank among natural gas plants in Iowa
- #7 of 42
- EIA plant code
- 1068
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| 1 | Natural Gas Fired Combustion Turbine | 63 MW | 51 MW | 1978 | Operating |
| 2 | Natural Gas Fired Combustion Turbine | 63 MW | 52 MW | 1978 | Operating |
| 3 | Natural Gas Fired Combustion Turbine | 63 MW | 53 MW | 1978 | 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 Iowa
| Turtle Creek Wind Farm LLC | Wind | 199 MW |
| Prairie Creek | Natural gas | 199 MW |
| Exira | Natural gas | 182 MW |
| Archer Daniels Midland Clinton | Coal | 180 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 189 MW solar plant and a 189 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 Iowa power plants · What Iowa actually generates