How much coal, natural gas, or petroleum is used to generate a kilowatthour of electricity?
The annual average amounts of coal, natural gas, and petroleum fuels used to generate a kilowatthour (kWh) of electricity by U.S. electric utilities and independent power producers in 2021 were:1
- Coal–1.12 pounds/kWh
- Natural gas–7.36 cubic feet/kWh
- Petroleum liquids–0.08 gallons/kWh
- Petroleum coke–0.82 pounds/kWh
The annual average number of kWh generated per amount of coal, natural gas, and petroleum fuels consumed for electricity generation by U.S. electric utilities and independent power producers in 2021 were:1
- Coal–0.89 kWh/pound
- Natural gas–0.14 kWh/cubic foot
- Petroleum liquids–12.69 kWh/gallon
- Petroleum coke–1.21 kWh/pound
The above amounts are based on data for 2021 from the Electric Power Annual, November 2022, and the simple averages of national-level annual data for electric utilities and independent power producers. They represent the annual average amounts for most of the electricity that is generated for sale in the United States, but exclude electricity generated in the commercial and industrial sectors. The fuel consumption data used for the above amounts exclude fuel use for useful thermal output in combined heat and power plants.
The actual amounts for a specific generator or power plant may vary considerably from those above. The exact amounts of fuel used to generate electricity depends on the efficiency or heat rate of the generator (or power plant) and the heat content of the fuel. Power plant efficiencies (heat rates) vary by types of generators (prime movers), by type and heat content of fuels, power plant emission controls, and other factors.
Two formulas can be used to calculate the amount of fuel used to generate a kilowatthour (kWh) of electricity:
- Amount of fuel used per kWh = Heat rate (in British thermal units [Btu] per kWh) divided by Fuel heat content (in Btu per physical unit)
- Kilowatthour generated per unit of fuel used = Fuel heat content (in Btu per physical unit) divided by Heat rate (in Btu per kWh)
Data sources available from the U.S. Energy Information Administration (EIA) for those calculations include:
- Table 7.3. Average Quality of Fossil Fuel Receipts for the Electric Power Industry ( xls )
- Table 8.1. Average Operating Heat Rate for Selected Energy Sources ( xls )
- Table 8.2 Average Tested Heat Rates by Prime Mover and Energy Source ( xls )
Monthly Energy Review, Appendices with fuel heat contents, electricity heat rates, and conversion factors
EIA publishes monthly and annual data on the amount of electricity generated and associated fuel consumption by electricity producers on a national and state level, and at individual power plants. This data can also be used to calculate fuel consumption per kWh of electricity generation and/or kWh generation per unit of fuel use.
- Data on total U.S. electricity generation (Table(s) 7.2 ) and fuel consumption for electricity generation (Table(s) 7.3)
- State-level historical electricity data files with annual and monthly electricity generation and fuel consumption
- Data on fuel consumption and electricity generation by fuel/energy source at individual U.S. power plants
1 Includes data for power plants with at least one megawatt of electric generation capacity but excludes fuel use for useful thermal output in combined heat and power plants.
Last updated: November 8, 2022 with data from the Electric Power Annual