Oil & Gas - Public Education - Coal Bed Methane
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Coalbed methane, or natural gas from coal, is a natural gas (principally methane) contained in coal seams.
Since 1994, Nova Scotians have been exploring the possibility of economic production of this gas, which is environmentally more acceptable than the mining and burning of coal.
Indeed, it could replace coal, at least in part, as a fossil energy source.
Check out our coal bed methane fact sheets and read on to learn more.
The process of converting plant material to coal generates large quantities of methane-rich gas, which is stored inside the coal.
The presence of this gas has been known for a long time - thanks, unfortunately, to explosions and outbursts associated with underground coal mining.
Only recently, however, has coal been recognized as a "reservoir rock" with enormous potential for a secondary energy resource.
Most gas in coal is stored on internal surfaces, which contain six to seven times more gas than the equivalent rock volume of a conventional gas reservoir.
And gas content generally increases with coal rank, depth of the coalbed, and reservoir pressure.
Fractures, or cleats, that permeate coalbeds are usually filled with water; the deeper the coalbed, the less water is present, but the more saline it becomes.
In order for gas to be released from the coal, its pressure must be reduced, and this is accomplished by removing water from the coalbed.
Large amounts of water, sometimes saline, are produced from coalbed methane wells, especially in the early stages of production.
While quantities of methane can be produced, water disposal options that are environmentally acceptable and economically feasible have yet to be refined.
Fact Sheets
An Introduction to Natural Gas from Coal - pdf
Natural Gas from Coal and the Environment - pdf