Landfill gas

Landfill gas is a mixture comprising mainly methane and carbon dioxide, formed when biodegradable wastes break down within a landfill as a result of anaerobic microbiological action. The biogas can be collected by drilling wells into the waste and extracting it as it is formed. It can then be used in an engine or turbine for power generation, or used to provide heat for industrial processes situated near the landfill site, such as in a brickworks. Landfill sites can generate commercial quantities of landfill gas for up to 30 years after wastes have been deposited. Recovering this gas and using it as a fuel not only ensures the continued safety of the site after landfilling has finished, but also provides a significant long term income from power and/or heat sales.