The Physics
An encyclopedia of scientific essays

Energy in a Ton of Coal

An educational, fair use website

search icon
Bibliographic Entry Result
(w/surrounding text)
The New Book of Popular Science. 2nd Edition. Danbury, CT: Grolier, 1998: 396. "Coal produces heat energies of 28 million to 38 million joules per 2.2 pounds" 25–35 GJ
Energy Information Sheets. Energy Information Administration. July 1998: 3. "Each ton of coal consumed at an electric power plant produces about 2000 kilowatt hours of electricity." 7.2 GJ
I.Y. Borg & C.K. Briggs. US Energy Flow. 1988: 15.
Fuel Energy Content (Btu)
Short ton of coal 22400000
23.63 GJ
Gabbard, Alex. Coal Combustion: Nuclear Resource or Danger. Oak Ridge National Laboratory. "An average value for the thermal energy of coal is approximately 6150 kilowatt-hour (kWh)/ton." 22.14 GJ

Ever wondered how much energy you could get out of a ton of coal, but never had the time to research it? Well, if you ever did, here's the answer to your pondering. On average, a ton of coal produces 21 to 22 gigajoules of energy.

The amount of energy produced by a ton of coal is largely dependent upon the type of coal being burned. There are four major categories of coal, each differing in composition and age. Lignite, also known as brown coal, is the least valuable of the four. Lignite is primarily used as fuel for steam to generate electric power. There is a compact form of lignite, called jet, which is sometimes used as an ornamental stone. Sub-bituminous coal is the next in line in terms of value. It is used primarily for electric power generation. Bituminous, a dense dark brown to black coal, is also used primarily for electric power generation. Substantial amounts of bituminous coal are also used for the production of coke, a solid residue rich in carbon. The most valuable of the four, is the anthracite. Anthracite is used for heating in residential and commercial buildings. The higher cost of anthracite is due to its low content of impurities and high content of carbon.

Lun Chen -- 2005

Bibliographic Entry Result
(w/surrounding text)
Theodore L. Brown, H. Eugene Lenay Jr., and Bruce E. Bursten. Chemistry the Central Science 7th Edition. Prentice Hall: 172.
Approximate Elemental Composition (%)
 CHOFuel Value (kJ/g)
Anthracite Coal (Pennsylvania)821231
Bituminous Coal (Pennsylvania)775732
31 J.
32 GJ.
Vince Calder, Richard J. Plano. Goal to Electricity Energy Transfer. Department of Energy, 12 October 2002. "Using an efficiency of 30% for transforming the heat energy of the coal into electrical energy and transmitting it to your light bulb (probably optimistic), we see that one pound of coal provides 4.11E6 Joules to your light bulb (I take 13,000 BTU/lb × 0.3 efficiency × 1054 Joules/cal) [sic. should be Joules/Btu — Ed.]." 9.2 GJ
Energy notes: Energy in natural processes & human consumption [pdf]. Selectra, Fall 2004.
Energy Content of Fuels (in Joules)
Energy UnitJoules Equivalent (S.I)
gallon of gasoline1.3 × 108
AA Battery103
standard cubic foot of natural gas (SCF)1.1 × 106
candy bar106
barrel of crude oil (contains 42 gallons)6.1 × 109
pound of coal1.6 × 107
pound of gasoline2.2 × 107
pound of oil2.4 × 107
pound of Uranium-2353.7 × 1013
ton of coal3.2 × 1010
ton of Uranium- 2357.4 × 1016
32 GJ

Did you know that coal can have as much energy per kg (if not more than) as dynamite? Coal is an organic compound made up mostly of carbon but also has small traces of hydrogen, nitrogen, sulfur and inorganic mineral compounds. It is developed over millions of years from decaying plant and animal remains under extreme pressure.

Coal is chiefly used as a fossil fuel but can also be used as a steel producing agent, medicine, fertilizer, and pesticide. Coal can also be "coked" which is the charring of coal originally intended to replace charcoal produced from wood. Because of its sulfuric properties, Coal could not be used for food nor alcohol production but was used in iron and steel production.

Coal is a mined product, and appears as a black or brown rock. Coal has many forms including lignite (brown coal, is the lowest rank of coal and used almost exclusively as fuel for steam-electric power) sub bituminous coal, bituminous coal (a dense coal, usually black, sometimes dark brown used primarily as fuel in steam-electric power generation), and anthracite (anthracite is the highest grade of coal, can yield double the energy that lignite can. Primarily used to heat residential and commercial establishments).When in its most efficient state, coal can yield on the order of 3.2 × 1010 J or 32 GJ.

Yulian Shtern -- 2006