US energy-related carbon dioxide fell by 2.8% in 2019, slightly below 2017 levels

U.S. energy-related carbon dioxide (CO2) emissions declined by 2.8% in 2019 to 5,130 million metric tons (MMmt), according to data in the U.S. Energy Information Administration’s (EIA) Monthly Energy Review. CO2 emissions had increased by 2.9% in 2018, the only annual increase in the past five years. Because of continuing trends in how much energy the U.S economy uses and how much CO2 that energy use generates, energy-related CO2 emissions in 2019 fell more than energy consumption, which declined by 0.9% in 2019, and gross domestic product, which increased by 2.3% in 2019.

The changes in U.S. energy-related CO2 emissions in 2019 offset the increase in 2018. The increase in 2018 was largely caused by increased energy use as a result of weather and was the largest increase in CO2 emissions since 2010, when the U.S. economy was recovering from an economic recession. Overall, U.S. energy-related CO2 emissions have fallen 15% from their peak of 6,003 MMmt in 2007.

In 2019, CO2 emissions from petroleum fuels—nearly half of which are associated with motor gasoline consumption—fell by 0.8%, and CO2 emissions from the use of natural gas increased by 3.3%. CO2 emissions from coal fell by 14.6%, the largest annual percentage drop in any fuel’s CO2 emissions in EIA’s annual CO2 data series dating back to 1973. The United States now emits less CO2 from coal than from motor gasoline.

Nearly all of the change in CO2 emissions in 2019 arose in the electric power sector. CO2 emissions from the residential and commercial sectors (associated with natural gas and distillate fuel oil consumption, for example) were nearly unchanged from 2018, and the increase in industrial sector CO2 emissions (+8 MMmt) partially offset a decrease in transportation sector CO2 emissions (-13 MMmt).

U.S. power sector emissions fell by 145 million metric tons in 2019, the second-largest decline on record for any sector. Total net electricity generation fell by 1.5% in 2019, but power sector CO2 emissions fell by even more (-8.2%), largely because of increases from renewable sources such as wind and solar. Electricity generation from coal fell, and the increase in natural gas-fired electricity generation was more limited. Because sources such as wind and solar have no fuel costs, when available, they are the first sources dispatched to meet electricity demand.

The transportation sector has been the largest source of energy-related CO2 emissions since surpassing the power sector in 2016. In 2019, the transportation sector’s energy-related CO2 emissions declined by 0.7% as a decrease in motor gasoline-related CO2 emissions (-0.7%) and diesel fuel-related CO2 emissions (-1.1%) more than offset an increase in jet fuel-related CO2 emissions (1.9%).