Wyoming is comparatively energy-rich, ranking 1st among the states in coal production and 7th in output of crude oil. The state's production of petroleum declined in the early 1990s as the result of declining reserves. Production in 2002 was 150,000 barrels per day; proved reserves totaled 489 million barrels. In 2001, reserves of natural gas were estimated at 18.4 trillion cu ft (0.52 trillion cu m); natural gas production totaled 1.44 trillion cu ft (0.04 trillion cu m) in 2002.
Wyoming has the three largest producing coal mines in the US and total recoverable coal reserves estimated at 6,100 million tons. In 1970, Wyoming's coal production accounted for only 1% of the US total. By 1998 the state's production had risen to 28% of national production. The Black Thunder mine in the Powder River Basin is the largest coal producer in the nation, with an output of 36.1 million tons in 1995. In 2000, the state's active mines produced 338.9 million tons of coal.
Electric power production (utility and nonutility) in 1999 totaled 43.6 billion kWh; total installed capacity was 6.1 million kW. In 1998, sales of electricity totaled 12.1 billion kWh. In 2000 Wyoming's total per capita energy consumption was 844 million Btu (212.7 million kcal), ranking it 3rd among the 50 states, behind Alaska and Louisiana. However, exported energy is counted as intrastate consumption, thus inflating per capita energy usage.