In 1999, South Dakota had an installed electrical capacity (utility and nonutility) of 2.89 million kW and produced 10.6 billion kWh of electricity, more than half of it sold to customers in other states. Over 63% of the power output came from hydroelectric sources and almost all the remainder from coal-fired plants. South Dakota marketed 1.1 billion cu ft (0.03 billion cu m) of natural gas in 2001. In 2000 South Dakota's total per capita energy consumption was 325 million Btu (81.9 million kcal), ranking it 31st among the 50 states.
South Dakota has very modest fossil-fuel resources. Lignite reserves were 366,100,000 tons; production of lignite and petroleum was negligible in 1998, however.