Coal Bed Methane (CBM) is ‘natural gas’ (methane) trapped in coal seams underground. To extract the gas, after drilling into the seam, it is necessary to ‘de-water’ the coal and so large amounts of water are pumped out to lower the pressure. It is often also necessary to stimulate the coal seam via fracking in order to extract the gas. This is technique is known as unconventional gas extraction. There are a similar catalogue of negative environmental and social effects as with Shale Gas. This includes methane migration, toxic water contamination, air pollution, increased carbon emissions and the industrialisation of the countryside. Impacts that are specific to CBM include depletion of the water table and potentially subsidence.
In common with other unconventional gas extraction, such as Shale Gas, CBM wells do not produce large amounts of gas per well and production declines very quickly. It is therefore necessary to drill large numbers of wells, covering a huge swaths of the landscape.
CBM exploitation began in the US and over 55,000 CBM well have been drilled in the last decade or so. In Australia, where it is know as Coal Seam Gas (CSG), over 5,000 CBM wells have been drilled in the last few years. In the UK CBM is more advanced than Shale Gas and full scale production may begin soon if the gas companies get their way.
How can I find out more?
This page is a very brief overview. Please visit the resources section of this website to find out more and read technical reports related to fracking. We also have links to a number of videos that can explain the issues and demonstrate the points above.