Americans use many types of energy
Petroleum (oil) is the largest share of U.S. primary energy consumption, followed by natural gas, coal, renewable energy (including hydropower, wood, biofuels, biomass waste, wind, geothermal, and solar), and nuclear electric power. Electricity is a secondary energy source that is generated from primary forms of energy.
Energy sources are commonly measured in different physical units to include barrels of oil, cubic feet of natural gas, tons of coal, and kilowatthours of electricity. In the United States, British thermal units (Btu), a measure of heat energy, is commonly used for comparing different types of energy. In 2014, total U.S. primary energy use was about 98.3 quadrillion (1015, or one thousand trillion) Btu.
The major energy users are residential and commercial buildings, industry, transportation, and electric power generators. The pattern of fuel use varies widely by sector. For example, petroleum oil provides 92% of the energy used for transportation, but only 1% of the energy used to generate electricity.
Domestic energy production meets about 89% of U.S. energy demand
In 2014, energy produced in the United States provided about 89% of the nation's energy needs. The remaining energy was supplied mainly by imports of petroleum.
The three major fossil fuels—petroleum, natural gas, and coal—accounted for most of the nation's energy production in 2014:
- Natural gas—31%
- Petroleum (crude oil and natural gas plant liquids)—26%
- Renewable energy—11%
- Nuclear electric power—9%
The mix of U.S. energy production changes
The three major fossil fuels—petroleum, natural gas, and coal—have dominated the U.S. energy mix for more than 100 years. There are several recent changes in U.S. energy production:
- The share of coal produced from surface mines increased significantly from 25% in 1949, to 51% in 1971, to 65% in 2013. The remaining share of coal was produced from underground mines.
- In 2014, natural gas production was higher than in any previous year. In recent years, more efficient and cost-effective drilling and production techniques have resulted in increased production of natural gas from shale formations.
- Total U.S. crude oil production generally decreased each year from a peak in 1970, but the trend reversed in 2010. In 2014, crude oil production was the highest since 1986. These increases were the result of increased use of horizontal drilling and hydraulic fracturing techniques, most notably in North Dakota and Texas.
- Natural gas plant liquids (NGPL) are hydrocarbons that are separated as liquids from natural gas at processing plants. They are important ingredients for manufacturing plastics and gasoline. Propane is the only NGPL that is widely used for heating and cooking. Production of NGPL fluctuates with natural gas production, but the NGPL share of total U.S. crude oil and petroleum field production increased from 8% in 1950 to 26% in 2014.
- In 2014, total renewable energy production and consumption reached record highs of nearly 10 quadrillion Btu each. Hydroelectric power production in 2014 was about 6% below the 50-year average, but increases in production from all other renewable sources increased the overall total contribution of renewable energy. Production of energy from wind and solar were at record highs in 2014.