Energy-related carbon dioxide (CO2) emissions are expected to decline in 2019 and 2020 after rising 2.8% in 2018, according to the U.S. Energy Information Administration. The 2018 increase was the largest in energy-related CO2 emissions since 2010.
Natural gas emissions, which increased nearly 10%, drove the rise in 2018, while emissions from petroleum, primarily used in the transportation sector, accounted for the largest share of total energy-related CO2. The largest factors contributing to the rise in 2018 were weather conditions and continued economic growth.
U.S. energy consumption in 2018 was 0.4% below the record set in 2007, and the weather contributed to the high level of consumption as 2018 was warm and the number of cooling degree days increased to a new record. Cooling degree days is an indicator of air-conditioning demand. Also, the winter months of 2018 were colder than the previous 10-year average, and heating degree days, an indicator of heating demand, were the highest since 2014. The temperature patterns led to record levels of electricity and natural gas consumption in 2018, according to EIA estimates. Electricity is used to meet nearly all air conditioning demand, and natural gas and electricity are the two most common heating fuels.
The weather is expected to be milder in 2019 and 2020 and lead to less energy consumption. However, energy-related CO2 emissions in 2019 and 2020 are expected to be higher than 2017 levels.
Changes in the economy can impact energy consumption and emissions. Growth in the Gross Domestic Product (GDP) is expected slow from 2.9% in 2018 to 2.7% in 2019 and 2% in 2020, according to the EIA. Industrial production is expected to rise faster than GDP in 2019 but slower than GDP in 2020. Industrial production is often more energy-intensive than other parts of the economy, and slower growth in industrial production in 2020 is expected to reduce energy and carbon intensity as a result of GDP growth.