Fossil fuels continue to be the most common sources of electricity generation in the United States, according to the U.S. Energy Information Administration. In all but 15 states, coal, natural gas or petroleum liquids were the most-used electricity generation fuel in 2017.
Since 2007, the number of states in which coal was the most prevalent electricity generation fuel has declined as natural gas, nuclear and hydroelectricity have increased market share. In its report, the EIA noted that electricity generated in one state might be consumed in other states.
In 2017, coal provided the largest generation share in 18 states, including Arkansas. In 2007, the fuel provided for the most electricity generation in 28 states. Between 2007 and 2017, the number of states in which natural gas provided for the most electricity generation rose to 16, from 11. Petroleum provided the most electricity generation in Hawaii.
In the United States, 32% of electricity was generated with natural gas in 2017, compared to 30% with coal. Of the 10 states in which coal was the primary fuel of electricity generation in 2007 but not in 2017, five are generating the majority of their electricity with natural gas, and the other five are generating the majority of their electricity with nuclear energy.
Nuclear power plants provided the most electricity in nine states in 2017, up from six in 2007. Hydroelectricity comprised the most electricity generation in six states in 2017, up from four in 2007. While hydro is the only renewable energy source to produce a majority share electricity in any state, this might change as a result of the addition of wind turbines in states such as Kansas and Iowa.