3rd largest plant in South Dakota · 788th nationally
Big Stone is a coal power plant in South Dakota with a nameplate capacity of 451 MW. It generates roughly 1.6M MWh per year — enough to power about 149,203 average U.S. homes.
Its capacity factor of 40% reflects intermittent or peaking operation. At 2222 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 (451 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 | Big Stone |
|---|---|
| Operator | Otter Tail Power Co |
| City | Big Stone City |
| County | Grant County |
| State | South Dakota |
| ZIP | 57216 |
| Coordinates | 45.30365, -96.51007 |
This plant highlighted in navy-ringed pin; other generators within 25 miles shown as fuel-colored dots.
| ID | Technology | Fuel | Capacity | Status | Online |
|---|---|---|---|---|---|
| 1 | Conventional Steam Coal | Subbituminous Coal | 450 MW | Operating | 1975 |
| D1 | Petroleum Liquids | Distillate Oil | 1.0 MW | Standby | 1975 |
| Owner | Location | Share |
|---|---|---|
| Otter Tail Power Co | Fergus Falls, MN | 5390.0% |
| Northwestern Energy - (Sd) | Sioux Falls, SD | 2340.0% |
| Montana-Dakota Utilities Co | Bismarck, ND | 2270.0% |
Ownership reported to EIA Form 860. Percentages reflect reported generator-level ownership share, averaged when a plant has multiple generators.
| CO₂ | 1.7M metric tons |
|---|---|
| SO₂ | 604 metric tons |
| NOₓ | 660 metric tons |
| CO₂ Rate | 2222 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 | MRO |
|---|---|
| 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.