Sioux
Sioux is a coal plant in St Charles County, Missouri, operated by Union Electric Co (MO). The operator has reported planned retirement dates for 1,099 MW of it, in 2028. Its oldest working unit dates from 1967, the second-earliest start among Missouri’s 8 coal plants.
Nameplate capacity, 2025
1,099 MW
974 MW net summer capacity
2 operable units
- Coal steam1,099 MW100%
Unit by unit, 1967 to 2025
operating in 2025reported planned retirementbar height follows unit size
Unit 1 Coal steam, 550 MW, 1967
Unit 2 Coal steam, 550 MW, 1968
Among Missouri’s plants
Largest plants in the state by nameplate capacity, with the plants ranked next to this one.
- 1Labadie2,389 MW
- 2Iatan1,754 MW
- 3New Madrid1,300 MW
- 4Callaway1,236 MW
- 5Thomas Hill1,182 MW
- 6Siouxthis plant
- 7Hawthorn1,046 MW
- 8Audrain Generating Station814 MW
Other rankings
- All US power plants
- 269th of 14,286
- Power plants in Missouri
- 6th of 137
- US coal plants
- 77th of 195
- Coal plants in Missouri
- 5th of 8
- Plants in the MISO (Midcontinent) balancing area
- 39th of 2,383
- Plants run by Union Electric Co (MO)
- 3rd of 28
- Biggest single unit, among Missouri’s plants
- 7th of 137
Operable units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| 1 | Coal steam | 550 MW | 487 MW | 1967 | Operating, retirement planned for 2028 |
| 2 | Coal steam | 550 MW | 487 MW | 1968 | Operating, retirement planned for 2028 |
Grid and site
- Balancing area
- MISO (Midcontinent)
- Reliability region
- SERC Reliability Corporation
- Highest grid connection voltage
- 138 kV
- Water source
- Mississippi River
- Nearest town on record
- West Alton
- Operator type
- Utility
- Coordinates
- 38.916°N, 90.290°W
Closest plants
| Plant | Runs on | Capacity | Distance |
|---|---|---|---|
| IL - Ameresco - Alton | Solar | 5 MW | 6.1 mi east |
| Mulberry Solar, LLC | Solar | 2 MW | 15.4 mi southeast |
| Hickory Solar | Solar | 110 MW | 15.6 mi north |
| Edwardsville Solar II | Solar | 2 MW | 17.2 mi southeast |
| Granite City Works | Other sources | 78 MW | 17.4 mi southeast |
| Venice | Natural gas | 586 MW | 18.4 mi south |
| Renewable Energy Center at BJH | Solar | 1.6 MW | 19.4 mi south |
| IKEA St. Louis 410 | Solar | 1 MW | 19.5 mi south |