Over the past 15 years, the U.S. electricity generation mix has shifted away from coal and toward natural gas and renewables, resulting in lower CO2 emissions from electricity generation. In 2019, the U.S. electric power sector produced 1,724 million metric tons (MMmt) of CO2, 32% less than the 2,544 MMmt produced in 2005. Lower CO2 emissions have largely been a result of a shift from coal to natural gas in the electricity generation mix. In 2005, coal made up 50% of U.S. electricity generation; that share declined to 23% in 2019. Conversely, natural gas increased from 19% of total generation in 2005 to 38% in 2019. ... (full story)