Fossil fuels—petroleum, natural gas, and coal—accounted for 79% of the 97 quadrillion British thermal units (quads) of primary energy consumption in the United States during 2021. About 21% of U.S. primary energy consumption in 2021 came from fuel sources other than fossil fuels, such as renewables and nuclear, according to data in our Monthly Energy Review. The 4-quad increase in U.S. primary energy consumption last year was the largest annual increase on record and was mostly attributable to a gradual return to pre-pandemic levels of activity. The increase in 2021 follows a 7-quad decrease in 2020, which was the ... (full story)