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Wellhead for methane capture at a landfill in Michigan.
Jim West

Wellhead for methane capture at a landfill in Michigan.

Landfill Methane Capture

Reduce SourcesElectricityShift Production
Reduce SourcesIndustryUse Waste
-1.6–2.18
Gigatons
CO2 Equivalent
Reduced / Sequestered
(2020–2050)
$-4.31
Billion $US
Net First Cost
(To Implement Solution)
$-21.55–-6.89
Billion $US
Lifetime Net
Operational Savings
Landfills generate methane as organic waste decomposes. Rather than getting released as emissions, that methane can be captured and used to produce electricity.

Solution Summary*

Over the course of a century, methane has 34 times the greenhouse effect of carbon dioxide. Landfills are a top source of methane emissions, releasing 12 percent of the world’s total. Landfill methane can be tapped, captured, and used as a fairly clean energy source for generating electricity or heat, rather than leaking into the air or being dispersed as waste. The climate benefit is twofold: prevent landfill emissions and displace coal, oil, or natural gas that might otherwise be used.

Most landfill content is organic matter: food scraps, yard trimmings, junk wood, wastepaper. Their decomposition produces biogas, a roughly equal blend of carbon dioxide and methane accompanied by a smattering of other gases. Ideally, those wastes would be recycled, composted, or digested. But as long as landfills are piling up, we must manage the methane coming out of them.

The technology to manage biogas is relatively simple. Dispersed, perforated tubes are sent down into a landfill’s depths to collect gas, which is piped to a central collection area where it can be vented or flared. Better still, it can be compressed and purified for use as fuel in generators, garbage trucks, or mixed into natural gas supply.

* excerpted from the book, Drawdown
Impact:

This solution sits at the bottom of the waste hierarchy. Landfill waste will decline as diets change, waste is reduced, and recycling and composting grow. What cannot, or should not, be combusted in waste-to-energy facilities will reach landfills as a last resort. These solutions will not be adopted globally overnight, so we assume landfill methane capture will continue to play a role. Combusting landfill methane for electricity generation can result in emissions reductions equivalent to 2.2 gigatons greenhouse gases emissions over a thirty-year period.