Coal power plant in South Dakota, United States of America. Approximate location 45.304611, -96.511033.
CoalSouth DakotaUnited States of Americasubcritical
Big Stone Power Plant is a 456 MW coal power station in South Dakota, United States of America. It is operated by NorthWestern Energy Group Inc [23%]; Montana-Dakota Utilities Co [22%]; Otter Ta. Based on its capacity (estimated), it can supply roughly 571k homes (estimated). It ranks #1344 of 10,938 United States of America power plants by installed capacity. Commissioned in 1975, it is around 51 years old — an older, legacy facility. In context, coal supplies about 16.3% of United States of America's electricity; the national grid averages 384 gCO₂/kWh (43.0% low-carbon) (2025).
Plant data: WRI Global Power Plant Database (CC BY 4.0), id GEM_coa_bigstone_unite.
Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.
The capacity and/or fuel fields on this page include a source-backed provenance label from GEM, an official registry, Wikidata, OSM, or a cross-source match.
capacity: GEM · 2026 · L100000104183; fuel: GEM GCPT
At 456 MW, Big Stone Power Plant is below the median coal plant in United States of America (558 MW). Technically it is described as subcritical. Coal plants burn pulverised coal to raise high-pressure steam for a turbine; they run as baseload but are the most carbon-intensive mainstream source and the first targeted for retirement or efficiency retrofits.
Capacity comparison computed from the WRI Global Power Plant Database; fuel-type context is general engineering background.
Installed capacity (MW), WRI Global Power Plant Database (CC BY 4.0).
Operated by NorthWestern Energy Group Inc [23%]; Montana-Dakota Utilities Co [22%]; Otter Ta.
This coal plant burns coal to raise high-pressure steam that spins a turbine-generator. It sits in a warm-summer humid continental climate (Köppen Dfb) — Northern Hemisphere, latitude 45.3°N — which shapes how much energy it can produce and how its output varies through the year.
Monthly mean temperature
Heating degree-days here run 80% above the median power plant in this dataset — a proxy for how much extra energy heated equipment must replace through its surfaces in winter.
Climate heat-demand index: 90/100 — this site sits in the top third of the power plants we cover by heating degree-days.
Climate normals: WorldClim 2.1 (1970–2000 monthly normals, 10 arc-min, CC BY 4.0); zone: Köppen-Geiger world climate classification (Kottek et al. 2006, 0.5° grid). Degree-days & heat-demand index computed by PowerAtlas — a modelled heat-demand proxy, not a measured site figure.
For a plant’s outdoor hardware — heat-recovery steam generators (HRSG), expansion joints, valves, flanges and their insulation — the local climate sets how fast unprotected steel and coatings degrade. This site sits in a mild atmospheric environment (estimated ISO 9223 class C2 — Low), with thermal cycling the leading environmental stress.
Higher environmental severity is exactly where protective removable insulation pays back most: a sheltered micro-climate slows corrosion, UV and thermal-cycling damage and extends outdoor hardware service life. This is an indicative site-climate context — not a condition assessment of any specific plant or operator.
Indicative estimate via the ISO 9223:2012 informative method (atmospheric corrosivity from temperature, time-of-wetness and airborne salinity), using WorldClim climate normals, the Köppen-Geiger class and coast distance. Indicative, not a measured corrosion rate.
The #434 largest coal power plant of 802 in United States of America by capacity.
United States of America has 802 coal power plants in this dataset, together about 621,194 MW of capacity.
Coordinates 45.304611, -96.511033 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
Big Stone Power Plant is a 456 MW coal power plant in South Dakota, United States of America, commissioned in 1975.
Its output is enough to supply roughly 570,651 homes (estimated).
Big Stone Power Plant is operated by NorthWestern Energy Group Inc [23%]; Montana-Dakota Utilities Co [22%]; Otter Ta.
