U.S. carbon dioxide emissions from energy use fall

Energy-related U.S. emissions of carbon dioxide fell 12% from 2005 to 2015, according to the Energy Information Administration (EIA).

Nearly 70% of these reductions were driven by electricity-generating plants shifting from coal to natural gas, which releases about half as much CO₂ as coal when burned.

The rest of the decline was a result of energy efficiency in homes, industry, and transportation; growing use of renewable energy; and milder weather, says EIA’s Paul Holtberg. Overall, energy-related activities were responsible for more than 80% of U.S. CO₂ emissions.

The drop in energy sector CO₂ emissions came despite a 15% growth in the U.S. economy over the same period, EIA reports. In fact, U.S. CO₂ emissions fell by 23% per unit of gross domestic product, says Holtberg, who credits transportation and home appliance efficiency as well as a general shift to less energy-intensive industrial production.

Holtberg predicts, however, that energy-related CO₂ emissions are likely to stabilize in the near term, along with natural gas prices, which are expected to flatten. The country’s trend away from coal matches global trends, but EIA’s report shows a greater U.S. CO₂ decline.

CO₂ emissions may rise for the U.S. chemical industry as it increases output to take advantage of cheap, abundant natural gas, Holtberg says. However, new U.S. chemical plants are likely to be more efficient than and draw production from older, less efficient facilities in other parts of the world. The result, he says, could be greater U.S. CO₂ emissions but lower global CO₂ emissions.