While global energy-related CO2 emissions remained flat in 2016, U.S. energy sector emissions fell by 1.7% according to the EIA. This drop continues the trend of declining energy-related emissions in the U.S. The 5,170 million metric tons emitted in 2016 is 14% lower than 2005 emissions.
The decrease in emissions from 2015 to 2016 was driven primarily by changes in fuel consumption in the power sector. Natural gas and petroleum consumption in the U.S. increased in 2016, and correspondingly emissions from petroleum and natural gas actually increased by about 1% each. However, this was more than offset by decreased coal consumption, with coal-related emissions falling by 8.6% in 2016. In addition to more generation from natural gas, EIA notes that renewable sources also helped to replace reduced generation from coal.
Another way EIA analyzes emission trends is through “carbon intensity,” which relates CO2 emissions to economic output. For example, 2016 saw a 1.7% decline in energy-related CO2 emissions and an initial estimate of 1.6% in economic growth, which combine to imply a 3.3% decline in the carbon intensity of the U.S. economy.
The EIA report also dives into the differences in emission trends among different consumption sectors. In recent years the power sector has shown the greatest decline in emissions, while the industrial, residential, and commercial sectors have been more consistent. The U.S. transportation sector was the only one with an increase in CO2 emissions from 2015 to 2016. Transportation-related emissions increased by 1.9% in 2016 and surpassed power sector emission levels.
As EIA has previously reported, its analysis shows that if the Clean Power Plan is not implemented coal will become the leading source of electricity generation by 2019. Consequently, the outcomes of EPA’s review of the Clean Power Plan and the continuing litigation over this rule will shape these trends in the future.