A spokesperson from campaign group Frack Off has described the extraction of coal bed methane as "as big a deal - if not bigger - than shale gas".
On their website the group describe it as "Shale Gas's less well known but equally destructive sibling in 'the family' of extreme energy methods". Extraction involves drilling into the rock formation containing the gas, sometimes adding stimulation like water or air to obtain the methane.
The group claim the closer proximity to the surface of the drilling increases risk of water contamination and methane leaks.
They say 12 planning applications have been approved in the UK for shale gas extraction, and 70 approved for coal bed methane.