The United States uses a wide range of energy sources to keep its vehicles moving; its buildings lighted, heated and cooled; and the wheels of industry moving forward. But even with advances in alternative energies, fossil fuels remain the nation's most used energy source. About 85 percent of America's energy needs are met by coal, natural gas and oil, according to the U.S. Department of Energy. They represent about two-thirds of our electrical needs and almost all energy requirements for transportation.
Fossil fuels may make up the largest portion of our energy supply, but they represent vastly different industries. Crude oil production, for example, is diminishing each year in the U.S. However, the demand is increasing, meaning the nation imports more than half of the crude oil needed each year. More than a fourth of the crude oil produced in the U.S. comes from the Gulf of Mexico. The top five crude oil-producing states are (in order of greatest-to-least production) Texas, Alaska, California, Louisiana and Oklahoma.
Most of the natural gas used in the U.S. goes for electrical power generation and industrial uses. The top four users of natural gas are Texas, California, Louisiana and New York. The the top four producing states are Texas, Wyoming, Oklahoma and New Mexico. Natural gas is a mix of hydrocarbon compounds, the largest of which is methane.
Coal is a more cost-effective energy source than crude oil and natural gas. However, it is considered a "dirtier" fuel because of the environmental effect of coal mining. About 90 percent of the coal mined in the U.S. goes to produce electricity. Less than 10 percent of the nation's coal supply is exported to about 40 countries. Canada has long been the biggest international customer for U.S. coal.
Major initiatives exist to explore and develop alternative energy sources, such as wind, solar, hydropower and geothermal. Solar energy has huge potential. The energy Earth receives from the sun in one year is 35,000 times greater than all the energy used by man in that time, according to the University of Utah.
Fossil fuels are appropriately named "non-renewable" energy sources. No new coal, oil or natural gas are being produced by the Earth. And while we may have hundreds of years of fossil fuel supply left, the drilling, mining, processing and consumption of those fuels contribute to environmental degradation and air pollution.