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Unit-of-Measure Equivalents
Unit
Equivalent
Kilowatt (kW) 1,000 (One Thousand) Watts
Megawatt (MW) 1,000,000 (One Million) Watts
Gigawatt (GW) 1,000,000,000 (One Billion) Watts
Terawatt (TW) 1,000,000,000,000 (One Trillion) Watts
Gigawatt 1,000,000 (One Million) Kilowatts
Thousand Gigawatts 1,000,000,000 (One Billion) Kilowatts
Kilowatthours (kWh) 1,000 (One Thousand) Watthours
Megawatthours (MWh) 1,000,000 (One Million) Watthours
Gigawatthours (GWh) 1,000,000,000 One Billion) Watthours
Terawatthours (TWh) 1,000,000,000,000 (One Trillion) Watthours
Gigawatthours 1,000,000 (One Million) Kilowatthours
Thousand Gigawatthours 1,000,000,000 (One Billion) Kilowatthours
U.S. Dollar 1,000 (One Thousand) Mills
U.S. Cent 10 (Ten) Mills
Source: Energy Information Administration, Office of Coal, Nuclear, Electric and Alternate Fuels, Electric Power Division.


In order to convert from U.S. units to metric units using the conversion factors shown in the following table, multiply the number of U.S. units (e.g., 2 pounds) times the conversion factor shown (0.45359237) to obtain the equivalent number in metric units (2 pounds times 0.45359237 pounds/kilograms = 0.90718474 kilograms).

Metric Conversion
Type of Unit U.S. Unit Times Conversion Factor Equals Metric Unit
Mass short tons (2,000 lb) x 0.907 184 7 = metric tons (t)
  pounds (lb) x 0.453 592 37a = kilograms (kg)
Volume barrels of oil (bbl) x 0.158 987 3 = cubic meters (m3)

 

cubic feet (ft3) x 0.028 316 85 = cubic meters (m3)

 

U.S. gallons (gal) x 3.785 412 = liters (L)
Energy British thermal units (Btu) x 1,055.055 852 62ab = joules (J)
aExact conversion.
bThe Btu used in this table is the International Table Btu adopted by the Fifth International Conference on Properties of Steam, London, 1956.
Notes: Spaces have been inserted after every third digit to the right of the decimal for ease of reading. Most metric units belong to the International System of Units (SI), and the liter and metric ton are acceptable for use with the SI units.
Sources: General Services Administration, Federal Standard 376B, Preferred Metric Units for General Use by the Federal Government (Washington, DC, January 27, 1993), pp. 9-11, 13, and 16. National Institute of Standards and Technology, Special Publications 330, 811, and 814. American National Standards Institute/Institute of Electrical and Electronic Engineers, SVIEEE Std 268-1992, pp. 28 and 29.

Useful Electricity Terms
  • An ampere is the unit of measurement of electric current produced in a circuit by 1 volt acting through a resistance of 1 ohm.
  • A Btu or British Thermal Unit is a standard unit for measuring the quantity of heat energy equal to the quantity of heat required to raise the temperature of 1 pound (16 ounces) of water by 1 degree Fahrenheit.
  • The Capacity Factor of a generating unit is the ratio of "the electrical energy produced by a generating unit for a given period of time" to "the electrical energy that could have been produced at continuous full-power operation during the same period."
  • A circuit is a conductor or a system of conductors through which electric current flows.
  • A current is a flow of electrons in an electrical conductor. The strength or rate of movement of the electricity is measured in amperes.
  • Efficiency is derived by dividing the heat content of 1 kilowatthour of electricity (3,412 Btu per kilowatthour) by the number of Btu contained in the input used to produce 1 kilowatthour.
  • Energy is the capacity for doing work--as measured by the capability of doing work (potential energy) or the conversion of this capability to motion (kinetic energy). Energy has several forms, some of which can be converted into another form useful for work. Most of the world's convertible energy comes from fossil fuels that are burned to produce heat thatis then used as a transfer medium to mechanical or other means in order accomplish tasks. Electrical energy is usually measured in watthours, while heat energy is usually measured in Btu.
  • Heat Rate is a measure of generating station thermal efficiency--generally expressed in Btu per net kilowatthour. It is computed by dividing the total Btu content of fuel burned for electricity generation by the resulting net kilowatthour generation.
  • An ohm is the unit of measurement of electrical resistance. It is the resistance of a circuit in which a potential difference of 1 volt produces a current of 1 ampere.
  • A watt is the electrical unit of power: that is, the rate of energy transer equivalent to 1 ampere flowing under a pressure of 1 volt at unit power factor.
  • A watthour is an electric energy unit of measure equal to 1 watt of power supplied to (or taken from) an electric circuit steadily for 1 hour.
For a complete list of EIA's electricity terms & definitions, go to: Electricity Terms.