Today, most of the energy consumed in the United States comes from fossil fuels — coal, petroleum, and natural gas, with crude oil-based petroleum as the dominant source of energy. Renewable energy resources supply a relatively small but steady portion, about 8% of U.S. total energy consumption. In the late 1950s, nuclear fuel began to be used to generate electricity, and in recent years has surpassed renewable energy sources.
The use of energy fuels has changed over time, but the change tends to occur slowly. In the long view of U.S. history, wood, a renewable energy source, served as the preeminent form of energy for about half of the Nation’s history. Coal surpassed wood’s usage in the late 19th century, and was, in turn, overtaken by petroleum products in the mid 1900s. Natural gas consumption experienced rapid growth in the second half of the 20th century, and coal use also began to expand as the primary source of electric power generation.