# Summary Table of Units of Energy Measurement

Updated on 02.02.2024

High School
Physics - chemistry

Below, a summary table of units of measurement used in the energy sector.

Name and abbreviationDefinition
("bbl" or "b")Unit of measurement for volume, specific to petroleum products.
1 barrel = 158.99 liters
1 barrel of oil equivalent corresponds to the energy produced when a barrel of oil is burned.
British Thermal Unit (BTU)Imperial unit of measurement for energy.
1 BTU ≈ 1055 joules (J)
Calorie (cal)

Energy measurement units. 1 cal = 4.184 J.

In food, the kilocalorie is generally used (1 kcal = 1,000 cal).

Cubic foot (CF)Imperial unit of measurement for volume.
1 cubic foot = 28.32 liters (l)
Degree Celsius (°C)Unit of measurement for temperature, derived from the International System of Units.
Gallon (gal)Imperial unit of measurement for volume.
1 U.K. gal = 4.546 liters (l); 1 U.S. gallon = 3.785 liters (l)
Horsepower (hp)Unit of measurement for power
1 horsepower = 735.5 watts (W)
Joule (J)

The basic unit of measurement for energy.

We often use kilojoules (kJ) up to exajoules (EJ), i.e. 1018 joules.

Kilowatt-hour (kWh)Commonly used unit of measurement for energy
kilowatt-hour = 3.6 × 106 joules (J)
Stere (st)Unit of measurement for a volume of wood.
1 stere = 1 cubic meter of stacked logs, including the empty spaces between them
Ton (t)Unit of measurement for weight.
1 ton of   equivalent equals the energy produced when a ton of coal is burned.
1 ton of coal equivalent = 0.66  , on average
Ton of oil equivalent (toe)1 ton of oil equivalent equals the energy produced when a ton of oil is burned.
Watt (W)Official unit of measurement for power.