4. Coal

A. Coal types, and a few coal products

Blast furnace gas—“A low-grade producer gas, made by the partial combustion of the coke used in the furnace and modified by the partial reduction of iron ore.” A Japanese greenhouse gas inventory reports: “Since the composition of BFG is unstable, the emission factors for BFG were established with annually calculated values.” (see here.)

Coal—“A solid, brittle, more or less distinctly stratified, combustible carbonaceous rock, formed by partial to complete decomposition of vegetation . . .” [Another definition seems to say the opposite: “A combustible layered rock, produced by the accumulation and preservation of vegetable matter in a decay-resistant environment.”] “In its most general sense the term ‘coal’ includes all varieties of carbonaceous minerals used as fuel, but it is now usual in England to restrict it to the particular varieties of such minerals occurring in the older Carboniferous formations.” “Coal is the result of the transformation of woody fibre and other vegetable matter by the elimination of oxygen and hydrogen in proportionally larger quantity than carbon . . .” When combusted, this is the most greenhouse-gas-emitting of the fossil fuels—peat possibly excepted. Peat, coal and graphite are closely related. As you will now see, coal’s categorizations are very inconsistent.

Anthracite (sometimes called hard, black or stone coal)—[Sometimes subdivided, in increasing order of hardness, into semianthracite, anthracite and meta-anthracite.] “The highest rank of economically useable coal . . . has a heating value of 15,000 Btu . . . virtually all mined in Pennsylvania . . . Used primarily for space heating and generating electricity.” “Used mainly for heating homes.” “The rarest and most desirable form of coal, representing less than 1% of known coal reserves.” “A smokeless coal of high fuel efficiency, though lower than semianthracite and semibituminous.” In any case, anthracite as a general category is the hardest sort of coal, with a moisture content of 2–4%. “As a rule, density increases with the amount of carbon.” However, even low-volatile bituminous coal sometimes contains more carbon than anthracite (see here, “table of Calorific Efficiencies). See also “About Coal,” II:18. Anthracite is said to be 90% carbon, but I have seen one proximate analysis of Virginia coal as low as 66.7%.* West Virginian “met” (metallurgical) coal was said to be anthracite, but according to the U.S. Energy Information Administration, “all the anthracite mines in the U.S. are located in northeast Pennsylvania.” I am told that anthracite sells for the highest price, but this may not be so simple. One advantage to anthracite is that it is less liable to spontaneous combustion when stored. Among the stuff’s detractors was Aldo Leopold who because he loved the smell of mesquite-roasted meat wrote bitterly: “Most poets must have subsisted on anthracite.”

Metallurgical coal—“The types of coal carbonized to make coke for steel manufacture, typically high in BTU value and low in ash content.” “Bituminous coals used to make coke are classified as ‘metallurgical’ . . . Not all types of bituminous coal are adaptable . . .”

Bituminous coal—“Sometimes called ‘soft coal’ . . . most commonly used for electric power generation. It has a heating value of 10,500–15,000 BTU . . . Mined chiefly in Appalachia and the Midwest.” Composed of 80–90% carbon. Another source says 45–86% carbon. Or, as a third source has it: “Fixed carbon and volatile matter are about equal.” My mid-20th-century Mechanical Engineers’ Handbook subdivides this category, in descending order of heat output, into bituminous (2–17% moisture) of various volatilities, and into subbituminous A, B and C (10–30%). “West Virginia leads production,” says a U.S. government source. Bangladesh also mines it. Most coal mentioned in Carbon Ideologies is bituminous.

Subbituminous coal—“A dull black coal with heating value ranging from 8,300–11,500 BTU . . . Used primarily for generating electricity and for space heating.” “A poor name for coal of higher rank than bituminous, although the name seems to imply the opposite meaning . . . Its heat efficiency is the highest of the coals.” One source proposes: 35–45% carbon. Much in Wyoming. Moderate liability to spontaneous combustion.

When heated in oxygen-restricted furnaces, bituminous coal often “cakes” (fuses or plasticizes), a property needed for making coke, from which steel is manufactured. In early-20th-century England, bituminous coal was known as “steam coal,” which does not precisely correspond with the West Virginia definition, for the latter apparently includes anthracite. “A medium soft classification . . . the most common and useful type mined in the U.S. . . . Used primarily for electric generation and for coke making for the steel industry.” The retired Kentucky miner and mining inspector Stanley Sturgill remarked: “I’m not that familiar with anthracite; most of it’s in Pennsylvania. Ours is called bituminous. It’s black.”—(“The semi-anthracite coals of South Wales are or were known as ‘dry’ or ‘steam’ coal.”)

Steam coal [West Virginia]—“Used primarily for electricity generation; generally lower quality than metallurgical coal.”

Lignite (brown coal)—“Nearly as soft as rotten wood.” “Either markedly woody or claylike in appearance.” “A brownish-black coal with generally high moisture content and low heating value (4,000–8,300 Btu per pound).” Usually 70% carbon or less (the previous sources say 25–35%). The moisture content is 30–45% (another source says 30–70%). “Mined primarily in the western U.S. and used for some electric generation and for conversion to synthetic gas.” More likely than its subbituminous cousin to spontaneously combust.

Coal sizes—“Lump, egg, stove, nut, pea, stoker, slack, etc. . . . Slack coal is all the coal passing through the screen of a given mesh.” Nut and slack size = 1 inch and larger.

Coal tar—“Coal yields about 6 per cent of its weight of tar.” [See coke for procedure.] As indicated by the famous “coal tree” of the West Virginia Coal Association (see II:10), coal tar derivatives are extremely useful in the production of an astonishing array of goods. One is dynamite, whose starting point is the light coal tar oil called toluene. Xylene used to be employed in explosive shells. “Naphthalene is the most abundant pure hydrocarbon obtained from coal tar,” advises an old explosives manual. The substance in question makes no bang in and of itself, but “nitrated naphthalenes . . . have been used in smokeless powder . . . and in high explosives for shells and for blasting.”

Coke—The grey solid remaining after the volatiles and coal tar are heated out of bituminous coal in an oxygen-poor vessel. “Harder and denser than charcoal* . . . has a high heat content, and is a valuable fuel.” “Coke is an excellent reducing agent . . . widely used in the smelting of metals,” especially iron and steel. Coke also can produce calcium carbide, a precursor of acetylene. “Coke from any coker is nearly all carbon, but . . . a small percentage of very heavy, very complex hydrocarbons may wrap themselves around” it. High-grade coke comes from removing those impurities in a calciner. “Western coals are weakly coking as compared with those of the Appalachian region.”

B. Coal mining and combustion terms

Bench—A layer of coal. Also called a seam.

Beneficiation—“The process whereby the extracted material is reduced to particles that can be separated into mineral and waste.” The procedures involved are “primarily mechanical, such as grinding, washing, magnetic separation, and centrifugal separation.”

Blast furnace—“A shaft furnace in which solid fuel is burned with an air blast to smelt ore for continuous operation.”

Dragline—“A huge piece of equipment with a large bucket suspended from the end of a boom that can extend more than 275 feet. The dragline can remove up to 200 tons of overburden in a single drag of its bucket across the work area . . .”

Highwall—“Unexcavated face of exposed overburden and coal in a surface mine. Highwalls must be recontoured following the extraction of coal.”

Gasification—See synthetic natural gas here.

IGCC—Integrated gasification combined cycle. As the name implies, this technology can gasify coal before burning it, thereby removing impurities and reducing the carbon dioxide released into the atmosphere. In 2007, Tepco and the Tohoku Electric Power Co. jointly built an experimental IGCC generator at Nakoso, 60-odd km south of the infamous Nuclear Plant No. 1. In 2015 Mr. Sakakibara Kohji, a Tepco group leader, said to me: “IGCC, that is the most advanced technology in the world. We are now doing some test demonstrations for the future. We are going to make a large demonstration furnace. However, because it is the most advanced technology, it is the most expensive.”

Longwall—A coal face in a deep or underground mine, under which heading see longwall mine.

Mantrip—[Also: “Man trip,” “man car,” “mancar.”] The conveyance to bring miners into a deep mine. In Upton Sinclair’s King Coal (1917) it was simply called a “trip.”

Open pit mine—See surface mine.

Overburden—The waste earth, rock and vegetation removed from a mine. This stuff sometimes contains heavy metals. Several West Virginians told me sad stories of overburdens being dumped into the “hollers” where they used to live.

Pillar—As it sounds. Pillars of coal are left unexcavated in a deep mine to prevent the ceiling from collapsing. The side of a pillar is called a rib; so is an entrance wall. [See underground mine: room-and-pillar mine.]

Producer gas—Emitted when coal (or coke) is incompletely combusted. “Composed of carbon monoxide, hydrogen, air and steam [not to mention our friend carbon dioxide] . . . Poison. Dangerous fire hazard when exposed to flame.”

Resources—The amount of coal which may be present in a deposit.

Reserve—The amount of a resource which is “recoverable using current technology.”

Proven reserves—“Can be recovered economically under current market conditions.”

Probable reserves—“Indicate a lower degree of confidence than proven reserves.”

Seam—See bench.

Stowing—Packing excavated areas with overburden in order to reduce the risk of cave-ins, spontaneous combustion, etcetera.

Subsidence—“A necessary evil in . . . underground operation. This can however be minimized with the adoption of stowing methods.”

Surface mine—“Permits a wide flexibility in production, which includes the ability to mine selectively and the potential for 100 per cent extraction [another part of the same document says “more than 90%”] of coal within the pit limits . . . Problems . . . include underground water managements [sic] . . . and undesirable environmental problems such as . . . dust . . . as well as waste disposal . . . [B]est suited to coal deposits of substantial horizontal dimensions.” Placer mines are surface mines more germane to gold than to coal, but here is one coal-relevant variety:

Auger mine—“The drill is placed at right angles to the coal seam and the cutting head is advanced into it, a full auger-flight length.” This is “a special type of borehole mining.” Yield rate: About 33%. “Sometimes employed to recover any additional coal left in deep overburden areas that cannot be reached economically by further contour or area mining.”

One common type of surface mine is the open pit mine, whose environmental and aesthetic costs are high. It is, of course, cheaper in dollars.

Mountaintop removal mine—“Coal buried at or near the summit of a large hill or mountain is sometimes best reached by entirely removing the elevated area. After reclamation is completed, the once mountainous terrain . . . is often left flat, making it suitable for farming, recreation or other purposes.”—“Rugged mountaintops and steep hollows are transformed into level or gently rolling land capable of agricultural, recreational, home, commercial and industrial development . . . Overburden can easily be segregated, including burial of toxic materials and recovery of suitable subsoils and topsoils to facilitate proper revegetation.” Sometimes euphemized to “mountain-top mining. “As of 2005, 2700 ridges had been impacted by mountaintop mining in the Central Appalachian area.”

Single bench mine—“A bench forms a single layer of operation above which coal and waste materials are excavated from the bench face . . . Bench heights normally range from 6 m to 10 m . . . but may approach 60 m in very special cases.”

Multiple bench mine—“Can be employed in massive, thick bedded coal deposit” farther underground than with a single bench mine. “If the pit is over 10 or 20 m deep, more than one bench probably will be needed . . . Benches are normally used for roadways either forming a spiral to the bottom of the pit or with ramps between the horizontal benches. Bench widths are also designed to provide protection for men and equipment from small slope failures.”

Strip mine—[Also: “Contour mine.”] More appropriate for thinner seams (0.6–10 m). “Usually accomplished by removing the overburden and coal from a strip across one dimension of the deposit. A parallel strip [is] then excavated in the opposite direction and the overburden . . . placed into the strip previously mined.” “Mining then continues laterally, circling the hillside and proceeding uphill.”

Valley fill mine—[Also: “Head-of-hollow fill mine.”] “A method where spoil is placed in narrow, V-shaped, steep-sided hollows free of mine openings or natural springs and located adjacent to the mining operation, is the technique most often employed in conjunction with mountaintop removal.”

Tipple—The spot outside a mine where the coal was tipped out of the cars. “Now refers to the surface structures of a mine, including the preparation plant and loading tracks.”

Underground mine—“If the depth of a coal deposit is such that the removal of the overburden makes surface mining unprofitable, [the] underground method should be considered . . . Factors . . . in choosing between a vertical or inclined shaft include the type of coal deposit and its depth.” Underground mines are of either the pillar or wall type, as follows:

Pillar type:

Block mine—“A series of entries, panel entries, rooms and cross cuts is driven to divide the coal into a series of blocks of approximately equal sizes which are then extracted on retreat.”

Room-and-pillar mine—“Cross-entries and panel entries are driven to ‘block out’ large panels of coal and rooms are turned off, usually at right angles from the entries.” Rooms and pillars are first “fully developed in a section,” going from near to far, and then pillars are mined out from far to near, the miners having previously installed anti-caving posts. About 50% of the coal thus mined is left behind. This method is somewhat prone to eventual subsidence.

Wall type:

Longwall mine—“Longwall mining employs a steel plow or rotating drum, which is pulled mechanically back and forth across a face of coal that is usually several hundred feet long. The loosened coal falls onto a conveyor . . .” “Two parallel headings are made 100–200 m [328–656 feet] apart and at right angles to the main heading. The longwall between the two headings is then mined away from the main heading . . . A moveable roof support system . . . advances as the coal is mined and allows the roof to collapse in a controlled manner behind it.” “The retreating method is almost exclusively used in the United States, whereas the reverse is true in most foreign countries.” Longwalling (“the most capital intensive but also the most capital efficient method of getting coal out of the ground”) leaves less coal behind (about 30%) than could a room-and-pillar mine. Hence it is far more prone to subsidence. The ill-starred Upper Big Branch mine (II:58) was a longwall operation.

Longwall mine with caving—The procedure described above. “Longwall” tends to mean “longwall with caving.”

Longwall mine with stowing—The mined areas are filled in with waste to prevent ground subsidence.

Shortwall mine—The primary difference between the two methods is the length of the working face. “In [the] short-wall system the maximum working face length is normally 45 to 55 m” [= 147.6–180.4 ft].

C. Some common coal pollutants [with related water terms, including pH] and coal diseases

Acid mine drainage—[Also: “AMD.”] See below, this section, yellowboy. See II:152.

Aluminum—A dangerous aquatic pollutant from coal. One mid-20th-century chemical analysis of “five coal ashes covering a wide range of fusibility” found aluminum oxide contents from 19.6 to 30.6%. See II:152.

Black lung—Pneumoconiosis or coal-worker’s pneumoconiosis (CWP), a debilitating and often fatal lung condition caused by breathing coal dust. It killed 100,000 American coal miners in the 20th century. From a mining methods handbook, 1978: “In the United States, the number of permanent disabilities and deaths of coal miners due to CWP is 3.5 times the number of disabilities and deaths due to all other mine incidents.” Senator Jay Rockefeller, 2013: “We thought, at one time, we had Black Lung on its heels. We were wrong.” See II:213.

Coal ash—“The inorganic residue that remains after burning the coal in a muffle furnace the final temperature of which is between 700 and 750 C.” “The ash contains heavy metals at levels toxic to marine life and to all who consume river-dwelling creatures.” [Sometimes coal ash is kept in slurry ponds, but the phrase “coal slurry” most often seems to refer to coal sludge.] “America’s coal plants produce 140 million tons of ash each year.” See II:184 for mention of spill in Dan River.

Coal dust—Nowadays defined as anthracite particles. A cause of black lung. At certain concentrations the stuff becomes highly inflammable. My grandfather’s Mechanical Engineers’ Handbook (1958), which did not restrict its definition to anthracite, reported, in the following order, ignition temperatures declining from 635 to 455° Celsius, and maximum explosive pressures increasing from 45 to 95 pounds per square inch: low, medium and high volatile coal, then, most dangerously, subbituminous coal.

Coal sludge—Also called coal slurry. “The liquid waste created when coal is washed and processed” so that it will pollute less when it is burned. The washing “happens after the coal is mined and before it is shipped to power plants.” It “contains toxic chemicals used to wash coal and heavy metals,” including “mercury, lead, arsenic, selenium, chromium, cadmium, and boron.” Kept in artificial lakes behind impoundment dams or else injected underground, it “can poison drinking wells.” See II:54–58 for testimony on the Buffalo Creek flood.

Conductivity—One measure of the metal content of a stream. The higher the conductivity, the more polluted it is. “It goes up as the water gets saltier. Fresh water in undisturbed Appalachian streams has a conductivity of under 100 and sea water has a conductivity of about 50,000.” By 2015, “several Alpha subsidiaries” and “Consol’s Fola Coal” were all found legally liable for conductivity pollution. According to Chad Cordell of the Kanawha Forest Coalition, “anything above 500 is bad.” In the Kanawha Forest he had found conductivities ranging from 20 to 3,500. (See II:114.)

MCHM—4-methylcyclohexane methanol, used to clean coal. The toxicity of this chemical was unknown when it leaked into the Elk River in January 2014, contaminating the water supply of 300,000 West Virginians. It smells like licorice. See II:170 for discussion of the Elk River spill.

Methane—See section 5A, here.

pH—A logarithmic scale from 1 (most acidic) to 14 (most alkaline). A pH of 7 is neutral. Six is 10 times more acidic than 7; 8 is 10 times more alkaline than 7. Thus a polluted West Virginia creek with a pH of 3 is 10,000 times more acidic than distilled water. The pH of 1 gram of sodium hydroxide solution in 1 liter of water is 14.0; and of the same solution, 10 times more dilute, 13.0; seawater is around 8.5; human blood is 7.35 to 7.45; reasonably decent drinking water weighs in at 6.5 to 8.0; oysters, at 6.1 to 6.6; human urine, 4.8 to 8; sour pickles, 3.0 to 3.4; apples, a surprising 2.9 to 3.3; lemons, 2.2 to 2.4; limes, 1.8 to 2.0; human gastric contents, 1.0 to 3.0.—According to the anti-mining activist Chad Cordell, the West Virginian legal standard for water was 6.0 to 9.0. “We typically see anywhere from 3.1 to about 7,” he told me.

Yellowboy—“Iron and aluminum compounds that stain streambeds” as a result of coal mining. Yellowboy can acidify a watercourse to a pH of 3 or even 2.

Pyrite + oxygen + water → “yellowboy” + sulfuric acid.

D. Companies, acronyms and localisms relevant to coal in Appalachia, Bangladesh and the world

Acronyms appear first if my informants commonly used them in quoted interviews. Otherwise I have used the full name.

Asia Energy—[AEC.] The foreign-owned company that sought to dig an open pit mine in Phulbari. The successor to BHP. “They are Australian, but their headquarters is in England and their business license is in Honduras. The gentleman who came was Garry Enlight.” See also BHP and Global Coal Management.

Barapukuria Workers’ Union—A labor organization, said to be “apolitical,” whose members all had some direct or indirect connection with the coal mine there. The union president asserted that the coal in Phulbari “will have to come out” (see II:245).

BDP—Bangladesh Development Power, a government utility. Most mined coal at Barapukuria was sold to BDP for electricity generation.

BGR—Bangladeshi Guards Rifles, or Border Guard Regiment, depending on whom I asked. I was told that they shot down the three shaheeds of Phulbari on August 28, 2006, and wounded up to 200 other people who were demonstrating against Asia Energy’s open pit mine.

BHP—Broken Hill[s] Properties [or Proprietary]. “They were based in the U.K. From 1998 BHP were doing surveys” around Phulbari, “and then they handed over the contract to Asia Energy.” According to Nazrul Islam, former consultant of BHP, “BHP did not want to create another environmental disaster like Ok-Tedi Copper Mine in Papua New Guinea where it had to quickly abandon the mine and paid hefty compensation to the surrounding inhabitants.”

DEP—Department of Environmental Protection, a West Virginia agency famous for its solicitude to the so-called regulated community.

Dinajpur—The district in which Phulbari and Barakupuria lay. “Dinajpur has always been known for its political uprisings. The people of Dinajpur had played a major role in Tebhaga Peasants movement in the 1940s . . .” “Dinajpur contains 30% reserve of . . . ground water of entire North Bengal.”

Freedom Industries—The company responsible for the MCHM spill that endangered 300,000 households in West Virginia. It went bankrupt but arranged to pay itself (see II:176, 176n–77n).

Global Coal Management—“Asia Energy changed its name to Global Coal Management (GCM) after August 2006 bloodshed and uprising.”

Holler—Since West Virginia is so mountainous, it abounds in secluded, originally lushly forested hollows, whose little homes and settlements have contributed a distinctive character to Appalachian identity. The hollers are sometimes used as dumping-grounds for the “spoil” (rubble) left over after mountaintop removal.

Massey Energy—This huge multinational coal company to many people’s minds morally if mostly not legally was responsible for the Upper Big Branch mining disaster in West Virginia, after which it became Alpha Natural Resources and presently went bankrupt on the Patriot Coal model.

MSHA—Mine Safety and Health Administration, another feeble regulatory body whose existence gave offense to the poor old regulated community. [Sometimes the “A” meant “Academy.”]

MT—Million tons.

MTR—Mountaintop removal.

National Committee to Protect Oil, Gas, Mineral Resources, Power and Ports—[Usually called just the National Committee.] A left-leaning organization that sought to halt Asia Energy’s open pit mine in Phulbari. “The National Committee was formed in 1998 when a group of leftists and other like minded individuals got together. It was started with the immediate objective of opposing the UNOCAL (A US-[b]ased company) stand that Bangladesh should export gas to India.” That year it “organized a long march from Dhaka to Chittagong port” and allegedly stopped a 199-year lease to a Barbados company that pretended to be American.

OECD—Organisation for Economic Co-operation and Development. As of 2012, its 34 members were: Australia, Austria, Belgium, Canada, Chile, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Israel, Italy, Japan, Korea, Luxembourg, Mexico, the Netherlands, New Zealand, Norway, Poland, Portugal, the Slovak Republic, Slovenia, Spain, Sweden, Switzerland, Turkey, the United Kingdom and the United States. Carbon Ideologies sometimes uses OECD statistics, especially those on coal. The International Energy Agency divided the world into OECD and non-OECD blocs. For instance, in 2012 it decreed: “The region previously called Latin America will now be known as non-OECD Americas.”

OSM—U.S. Office of Surface Mining, whose ominous discoveries regarding coal slurry dams are mentioned on II:162.

Patriot Coal—This spin-off of Peabody Coal conducted MTR in West Virginia and elsewhere, then presently declared bankruptcy, paying massive bonuses to the higher-ups and renouncing significent pension obligations to its retirees.

Phulbari—A subdistrict of Dinajpur. Here Asia Energy attempted to dig an open pit coal mine. When I finished Carbon Ideologies the corporation was still trying. “The coal-field will extend over 135 square kilometers,” and 50,000 to 200,000 people would be displaced.

Regulated community—A phrase employed by pro-coal entities to refer to industries (such as Big Coal) which are (supposedly unfairly) burdened with environmental and safety regulations. I have expanded it to refer to the businesses of all carbon ideologies. From the vantage point of an imagined 25th century, Hermann Hesse wrote: “It took long enough in all conscience for realization to come that the externals of all civilization—technology, industry, commerce and so on—also require a common basis of intellectual honesty and morality.” That common basis was the antithesis of our regulated community.

Thana—[Bangladesh.] A police subdistrict. One such was Phulbari, where the three shaheeds were shot down in 2006.

UBB—Upper Big Branch, a deep mine near Montcoal, West Virginia. Site of the coal mine explosion that killed 29 men in 2010. The result of greed.

UP—Union of Peasants, or Peasant Organization, a left-leaning Bangladeshi entity that was present in Phulbari when Asia Energy tried to dig an open pit mine there.

WV-A—West Virginia American Water.

E. Units and conversions

Ton—A short or American ton is 2,000 pounds. A long or British ton is 2,240 pounds. A metric ton is 1,000 kg or 2,204.6 lbs. See also refrigeration ton in section 2, here.

The U.S. Department of Energy claimed in 1993 that each [short] ton of coal consumed at a power plant generates about 2,000 kilowatt-hours of electricity.

Ton of coal equivalent or tce—“One [metric] tonne of coal equivalent is 7 million kilocalories.”—International Energy Agency. Since 1 kcal = 3.968 BTUs, then 1 tce = 27,776,000 BTUs. At .907×, a U.S. ton of coal equivalent would be 25,192,832 BTUs.

1 tce = 29.3 GJ [gigajoules] = 0.7 toe [ton of oil equivalent]

Ton of oil equivalent or toe—Again, this is a metric ton. One toe is 39,680,000 BTUs. At 0.907×, a U.S. ton of coal equivalent would be 35,989,760 BTUs. For more discussion of this unit, see section 6E, here.

Some fuel conversions:

Crude oil: 1.034 toe

Gasoline: 1.128 toe

Jet fuel: 1.133 toe

Liquid petroleum gas: 1.195 toe

1 trillion cubic feet of natural gas roughly = 25 mtoe [million tons of oil equivalent].

1 toe = 11.6 MWh

To convert from BTUs of electricity to pounds of oil, coal or natural gas needed, assuming a power plant efficiency of 30%:

For oil, divide BTUs by 17,995. [In other words, multiply × (1 toe [1 U.S. ton of oil / 35,989,760 BTUs] ) × [2,000 lbs / ton]. To express power plant inefficiency, multiply × 3, for a final figure of [BTUs needed / 5,998] = lbs of oil required.

For coal, divide BTUs by 12,596. [In other words, multiply × (1 tce [1 U.S. ton of coal / 25,192,832 BTUs] ) × [2,000 lbs / ton]. To express power plant inefficiency, multiply × 3, for a final figure of [BTUs needed / 4,198] = lbs of coal required.

For natural gas, divide BTUs by 24,021. [In other words, multiply × 1 cu ft / 1,000 BTUs] × [0.04163 lbs/cu ft = density of methane]. To express power plant inefficiency, multiply × 3, for a final figure of [BTUs needed / 8,007] = lbs of natural gas required.