The barrel of oil equivalent (BOE) is a

unit of energy Energy is defined via work, so the SI unit of energy is the same as the unit of work – the joule (J), named in honour of James Prescott Joule and his experiments on the mechanical equivalent of heat. In slightly more fundamental terms, ...

based on the approximate energy released by burning one

barrel A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden stave (wood), staves and bound by wooden or metal hoops. The word vat is often used for large containers ...

(, or about ) of

crude oil Petroleum, also known as crude oil or simply oil, is a naturally occurring, yellowish-black liquid chemical mixture found in geological formations, consisting mainly of hydrocarbons. The term ''petroleum'' refers both to naturally occurring u ...

. The BOE is used by oil and gas companies in their financial statements as a way of combining

oil An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) and lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturate ...

and

natural gas Natural gas (also fossil gas, methane gas, and gas) is a naturally occurring compound of gaseous hydrocarbons, primarily methane (95%), small amounts of higher alkanes, and traces of carbon dioxide and nitrogen, hydrogen sulfide and helium ...

reserves and production into a single measure, although this energy equivalence does not take into account the lower financial value of energy in the form of gas. The U.S.

Energy Information Administration The U.S. Energy Information Administration (EIA) is a principal agency of the U.S. Federal Statistical System responsible for collecting, analyzing, and disseminating energy information to promote sound policymaking, efficient markets, and pub ...

defines the barrel of oil equivalent as about . The value is necessarily approximate as various grades of oil and gas have slightly different heating values. If one considers the

lower heating value The heating value (or energy value or calorific value) of a substance, usually a fuel or food (see food energy), is the amount of heat released during the combustion of a specified amount of it. The ''calorific value'' is the total energy release ...

instead of the

higher heating value The heating value (or energy value or calorific value) of a substance, usually a fuel or food (see food energy), is the amount of heat released during the combustion of a specified amount of it. The ''calorific value'' is the total energy release ...

, the value for one BOE would be approximately 5.4 GJ (see

tonne of oil equivalent The tonne of oil equivalent (abbreviated toe) is a unit of energy defined as the amount of energy released by burning one tonne of crude oil. It is approximately 42 gigajoules or 11.630 megawatt-hours, although as different crude oils have diffe ...

). Typically is equivalent to one BOE. The

United States Geological Survey The United States Geological Survey (USGS), founded as the Geological Survey, is an agency of the U.S. Department of the Interior whose work spans the disciplines of biology, geography, geology, and hydrology. The agency was founded on Mar ...

gives a figure of of typical natural gas. Due to the risk of confusion The

Society of Petroleum Engineers The Society of Petroleum Engineers (SPE) is a 501(c)(3) not-for-profit professional organization. SPE provides a worldwide forum for oil and natural gas exploration and production (E&P) professionals to exchange technical knowledge and best prac ...

recommends in their style guide that abbreviations or prefixes M or MM are not used for barrels of oil or barrel of oil equivalent, but rather that thousands, millions or billions are spelled out. Common prefixes for readers familiar with the metric system are k for thousand, M for million and G for billion while other readers might be more familiar with M for thousand, MM for million and B for billion. All those multiples are commonly combined with barrel of oil equivalent from the level of individual production units output per day to level of

petroleum reserves Oil and gas reserves denote ''discovered'' quantities of crude oil and natural gas from known fields that can be profitably produced/recovered from an approved development. Oil and gas reserves tied to approved operational plans filed on the da ...

. Metric regions commonly use the

(toe), or more often million toe (Mtoe). Since this is a measurement of mass, any conversion to barrels of oil equivalent depends on the density of the oil in question, as well as the energy content. Typically 1 tonne of oil has a volume of . The United States EIA suggests 1 toe has an average energy value of .

References

Petroleum economics Units of energy Equivalent units

See also

References