Gas from landfill is a valuable resource
Modern landfill sites have very little in common with the refuse tips of an earlier age, when waste was dumped in a heap and there were no environmental restrictions. EU-wide legal requirements now require sophisticated systems to prevent harmful substances from spreading into the surroundings.
Proactive landfill sites now also install gas recovery equipment to collect the landfill gas, which is mostly methane. Methane is formed in the absence of oxygen, when anaerobic bacteria take over decomposition. Leakage of this gas into the atmosphere contributes to the greenhouse effect, but if it is collected and used correctly it can be used to generate useful electricity and heat.
The extraction of landfill gas is increasingly common at Swedish landfill sites. In other parts of the world the technology is less widespread and leaks represent a significant environmental problem.