Organic material buried in a landfill decomposes by anaerobic microbial action. Complete decomposition usually takes more than 20 years. One of the by-products of this decomposition is biogas.
Landfill gas contains about:
15% other gases
Landfills' main contribution to greenhouse gas emissions is in the form of methane (CH4) contained in landfill gas.
Veolia has developed and implemented innovative technologies to produce electricity from landfill gas, contributing to the campaign against the greenhouse effect.
During and after the working life of a landfill, gas generated by the waste can be drawn off and converted to energy. Our landfill sites in the UK currently export approximately 55MW of energy to the National Grid.