52nd largest plant in Illinois · 1263rd nationally
Marion is a coal power plant in Illinois with a nameplate capacity of 249 MW. It generates roughly 708.9k MWh per year — enough to power about 67,516 average U.S. homes.
Its capacity factor of 32% reflects intermittent or peaking operation. At 3232 lb CO₂/MWh, its emission rate sits above the national grid average of roughly 800 lb/MWh.
Ghost bars are each month's theoretical maximum (249 MW nameplate × hours in the month). Filled bars are actual net generation reported to EIA Form 923. The gap between them is capacity factor made visible.
| Plant Name | Marion |
|---|---|
| Operator | Southern Illinois Power Coop |
| City | Marion |
| County | Williamson County |
| State | Illinois |
| ZIP | 62959 |
| Coordinates | 37.61975, -88.95311 |
This plant highlighted in navy-ringed pin; other generators within 25 miles shown as fuel-colored dots.
| ID | Technology | Fuel | Capacity | Status | Online |
|---|---|---|---|---|---|
| 4 | Conventional Steam Coal | Bituminous Coal | 173 MW | Retired | 1978 |
| 5 | Natural Gas Fired Combustion Turbine | Natural Gas | 75.0 MW | Standby | 2003 |
| 6 | Natural Gas Fired Combustion Turbine | Natural Gas | 75.0 MW | Standby | 2003 |
| 1 | Conventional Steam Coal | Bituminous Coal | 33.0 MW | Operating | 1963 |
| 2 | Conventional Steam Coal | Bituminous Coal | 33.0 MW | Operating | 1963 |
| 3 | Conventional Steam Coal | Bituminous Coal | 33.0 MW | Operating | 1963 |
| CO₂ | 1.1M metric tons |
|---|---|
| SO₂ | 2.3k metric tons |
| NOₓ | 426 metric tons |
| CO₂ Rate | 3232 lb/MWh |
Annual totals and CO₂ rate reported by EPA eGRID for 2023. Reference averages are approximate U.S.-wide figures from the same dataset.
| NERC Region | SERC |
|---|---|
| Balancing Authority | Midcontinent Independent Transmission System Operator, Inc.. |
Coal plants burn pulverized coal to boil water and spin steam turbines. They emit substantial CO₂, SO₂, and NOₓ along with mercury and particulate matter. Modern units include scrubbers and selective catalytic reduction; older units are increasingly being retired or converted to natural gas as economics shift.