Tonnes Of Oil Equivalent to British Thermal Units (toe to BTU)

1 tonne of oil equivalent equals 39,683,207.19 British thermal units (rounded).

1 tonne of oil equivalent = 39,683,207.19 British thermal units

How to convert tonnes of oil equivalent to British thermal units

To convert tonnes of oil equivalent to British thermal units, multiply the number of tonnes of oil equivalent by 39,683,207.19. The factor is rounded to 10 significant digits. To go the other way, multiply British thermal units by 2.519957611×10⁻⁸ (rounded).

British thermal units = tonnes of oil equivalent × 39,683,207.19

Example: 10 tonnes of oil equivalent = 396,832,071.9 British thermal units.

The 'calorie' on food labels is really a kilocalorie. The thermochemical calorie (4.184 J) is used here unless marked IT.

About these units

Tonne Of Oil Equivalent (toe)

Metric (SI)Current unit

Exactly 41.868 GJ, the energy released by burning one tonne of crude oil. A standard unit in energy statistics.

Energy statisticians need a way to add up coal, gas, hydro and oil in one column, and the tonne of oil equivalent does that by expressing everything as the heat from burning a tonne of crude oil. Because crude oils differ in calorific value, the figure is a convention rather than a measurement, and more than one version circulates. The International Energy Agency uses 41.868 gigajoules, which is the figure used here. Other sources use 41.85 gigajoules, and a version based on the thermochemical calorie gives 44.769.

In everyday terms the IEA value is 11,630 kilowatt-hours, or about 39.7 million British thermal units, and it equals 10 gigacalories on the international steam table calorie. Smaller and larger steps are the kilogram of oil equivalent (one thousandth) and the megatoe and gigatoe. One toe is about 7.33 barrels of oil equivalent and 1.42857 tonnes of coal equivalent. Converting electricity into toe depends on an assumed plant efficiency, so national tables can differ.

1 tonne of oil equivalent = 41,868,000,000 joules (exactly).

Sources: Wikipedia: Tonne of oil equivalent; Wikipedia: Calorie

British Thermal Unit (BTU)

US & ImperialCurrent unit

The International Table BTU, exactly 1,055.05585262 joules. The energy to heat one pound of water by one degree Fahrenheit; used for heating, cooling and gas appliances in the US.

Few energy units come in as many versions as the British thermal unit. It was defined as the heat needed to raise one pound of liquid water by one degree Fahrenheit, but because water's heat capacity shifts slightly with temperature, definitions differ by up to 0.5 percent: about 1,054.35 J for the thermochemical Btu, 1,054.80 J at 59 degrees Fahrenheit (used for American natural gas pricing), 1,054.68 J at 60 degrees (mainly Canadian), and 1,059.67 J at 39 degrees. A 1942 note suggests the term apparently arose in the United States and was later adopted in Britain.

The version on this site is the International Table Btu, about 1,055.06 J, which comes from the international steam table conferences that tied heat units to the joule. Joule's own 1850 experiments gave 772.692 foot-pounds of work per Btu, the number that first linked heat to mechanical effort.

Today the Btu survives in natural gas pricing (MMBtu means a million Btu), US building energy reporting, and equipment ratings in Btu per hour. One ton of air-conditioning is 12,000 Btu/h, or 3.52 kW. A single wooden kitchen match burning releases about one Btu.

1 British thermal unit = 1,055.055853 joules (approximately).

Sources: Wikipedia: British thermal unit; Wikipedia: James Prescott Joule

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