Changes in the mix of fuels used to generate electricity, along with a slowdown in the growth of demand for power, have contributed to a 28 percent decline in carbon dioxide emissions since 2005, according to the U.S. Energy Information Administration.
EIA calculated that CO2 emissions from the United States’ electric power sector totaled 1,744 million metric tons (MMt) in 2017, the lowest level since 1987. (CO2 emissions from outside the power sector only fell by 5 percent in that same time period.)
U.S. electricity demand has decreased in six of the past 10 years as industrial demand has declined and residential and commercial demand has remained relatively flat.
If electricity demand had continued to increase at the rate it did for the 10 years prior to 2005 and if the mix of fuels used to generate electricity had stayed the same, CO2 emissions would have been 645 MMt higher in 2017. But, instead, in 2017, “noncarbon” resources, including renewable resources, accounted for 38 percent of the resources, up from 28 percent in 2005