The generation of methane gas for use as a fuel is a potential benefit of treating sludge, a waste water by-product, by anaerobic digestion. The gas produced from the sludge digestion process in Ireland's largest waste water treatment facility at Ringsend in Dublin supplies some 50% of the heating requirements of the plant. Other sewage treatment plants also recover energy from methane gas to heat the sludge digestion process.
Funding for the inclusion of energy recovery facilities in waste water treatment plants is available, where appropriate, from my Department under the Water Services Investment Programme.