The most common use of coal seam gas is for electricity generation. Gas-fired power stations create less than half the greenhouse gas emissions of equivalent-sized coal fired power stations.


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Coal seam gas is a form of natural gas trapped in coal beds by water and ground pressure. Coal seam gas refers to the methane gas lining the open fractures between the coal (called the cleats) and the inside of pores within the coal (called the matrix).

Coal seam gas accounted for 73.3 petajoules (PJ) of gas supply in Queensland in 2006, or 63 percent of total demand of 117 PJ.

Arrow Energy uses an advanced technological process to extract coal seam gas from the coal seams.

It begins with the drilling of a 300 to 500 metre deep well. The top section of the well is cased with steel and cement to prevent the loss of water from any upper aquifers.

A special rotating blade is lowered to the bottom section of the well to ream out cavities in the coal seams. This production zone is then lined with alternating slotted and blank steel casing.

Water, released from the coal, is pumped from the well using a rotating screw. This lowers the water pressure in the coal seam and allows the gas to separate from the coal and flow into the well.

The gas and water rise to the surface through separate pipes. The water is transported through underground pipes to a dam for possible reuse and recycling. The gas passes through a separator near the well head to remove water traces before being piped to a processing facility to be compressed and dehydrated. The gas is then fed into commercial pipelines.

At the Daandine Power Station, coal seam gas is used to fuel engines that turn large electrical generators. The electricity produced is delivered to consumers through a network of high voltage transmission lines. This is known as the transmission grid. The Daandine Power Station converts two petajoules of gas each year into enough electricity to power 10,000 homes.