Coalbed Methane (CBM) commonly is referred to as an “unconventional” form of natural gas because it is primarily stored through absorption to the coal itself rather than in the pore space of the rock.
Nonrenewable energy resources include the fossil fuels as natural gas, petroleum, shale oil, coal and peat. Fossil fuels are both energy dense and wide spread, with most of the world’s industrial, utility and transportation sectors rely on the energy contained in them. Energy obtained from coal constitutes 60% of the total proven recoverable reserves and around 80% of estimated additional resources, proving to be largest of the world’s available supplies. Coal is the most abundant fuel on earth and the primary fuel for consumption of electricity. Around 65% of the total world’s coal resources are held by three countries, the Russia, the U.S.A and the People’s Republic of China.
CBM is an emerging energy source that rivals conventional natural gas in composition and heating value. Historically a mining hazard, CBM is now extracted in many areas to improve mine safety and become a valuable part of the energy mix. It is also produced from abandoned mines and from coals too thin or deep to be mined. The most common use of CBM is in natural gas pipelines for domestic, commercial, and industrial fuel. Some of the other more common uses are boiler fuel in gas turbines to generate electricity at cogeneration plants; chemical feedstock for methanol, ammonia, and other chemicals; raw material for the production of liquefied natural gas (LNG) and gas products, in which natural gas and coal are burned together to use coals that are marginally compliant with clean air laws.
CBM accounted for more than 8% of natural gas production in the U.S. Coal beds are an attractive prospect for development because of their ability to retain large amounts of gas -- coal is able to store six to seven times more gas than an equivalent volume of rock common to conventional gas reservoirs.
Reference:
Western Organization of Resource Councils (WORC)
http://www.worc.org
