Landfill Gas Recovery: Turning Methane into Energy
Every active landfill breathes out gas. Capture it and it becomes fuel; let it leak and it becomes a potent greenhouse gas. Here is how the capture systems work and why they matter.
When organic waste — food scraps, paper, yard trimmings — decomposes without oxygen inside a landfill, bacteria produce a gas that is roughly 50% methane and 50% carbon dioxide, with traces of nitrogen, oxygen and trace contaminants. Methane is about 28–34 times stronger than CO₂ at trapping heat over a 100-year span, so uncontrolled landfill emissions are a major climate problem. The good news: the same gas is a usable fuel.
How a Collection System Works
- Wells — vertical or horizontal pipes drilled into the waste body pull gas out by suction.
- Header pipes — a network carries the gas to a central plant.
- Blower & flare — a blower maintains negative pressure; if the gas cannot be used, it is burned (flared) so methane becomes CO₂, which is far less warming.
- Treatment — condensate and impurities are removed before the gas is burned in an engine, turbine or boiler.
What the Gas Becomes
Captured landfill gas (LFG) is most often used to generate electricity, feed a boiler for district heat, or — after upgrading to pipeline quality — injected as renewable natural gas. In some cities it even powers nearby factories or is used as a vehicle fuel. A single large landfill can power thousands of homes.
Why Capture Beats Leakage
Flaring cuts the warming impact dramatically, and using the gas for energy displaces fossil fuels on top of that. Beyond climate, capture reduces odour, landfill fires and local air pollutants. Many regions now require active landfills above a certain size to install gas collection, and older closed landfills are being retrofitted.
Related Reading
Compare disposal routes in our landfill vs closed-loop guide, see how burning waste makes energy in waste-to-energy, and read about anaerobic digestion — the cleaner alternative that captures biogas before waste is buried.
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