Power Plants in South Dakota

South Dakota holds 7,670 megawatts of nameplate capacity across 54 plants, ranking 41st of the 50 states and DC. This capacity represents what the equipment could produce running flat out; actual generation differs because a megawatt of solar and a megawatt of nuclear appear the same here and produce very different amounts of electricity over a year.

Wind dominates the fleet at 45.1% of capacity, followed by hydro and natural gas each at 21.5%. The largest plants are the Oahe hydro station with 786 megawatts and Big Bend Dam with 538 megawatts, both in the Missouri River system. The Big Stone coal plant holds 451 megawatts, the Angus Anson natural gas facility 406 megawatts, and Astoria Station, which came online in December 2021, adds 349 megawatts of natural gas capacity. Coal, solar, and other sources make up the remainder in smaller shares.

The state's generating plants span from Spearfish Hydro, first online in October 1912, to RE Solar, LLC, which entered service in December 2024. This range encompasses more than a century of additions to the fleet.