Landfill Gas Generation Calculator

Work out landfill gas generation instantly with clear inputs, formula shown and shareable results.

About Landfill Gas Generation Calculator

First-order decay models express annual methane generation as waste in place times methane potential times the decay constant. Methane potential is 50-170 m3 per tonne depending on organic content, and k ranges from 0.02 per year in arid sites to 0.09 in wet ones. Collection efficiency of 60-85% is achievable with active wells and capping.

Formulas

First-order decay

Annual methane = waste in place x L0 x k

Energy

Energy = methane x 9.94 kWh/m3; electrical = energy x engine efficiency

Worked example

With the default values below, Landfill Gas Generation Calculator returns Methane Collected Per Year of 3,750,000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Waste In Placeminimum 0 tonnes: 1,000,000 tonnes
Methane Generation Potentialminimum 0 m3 CH4 per tonne: 100 m3 CH4 per tonne
Methane Generation Rate Constantminimum 0 per year: 0.05 per year
Gas Collection Efficiencyaccepts 0–100 %: 75 %

Results

Methane Collected Per Year: 3,750,000
Total Methane Generated: 5,000,000
Landfill Gas Volume: 6,818,182
Electrical Generation Potential: 14,164.5

Step by step

1Values used
2First-order decay
3Energy
4Methane Collected Per Year= 3,750,000
5Total Methane Generated= 5,000,000
6Landfill Gas Volume= 6,818,182
7Electrical Generation Potential= 14,164.5

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Landfill gas is explosive and asphyxiating and its methane emissions are regulated. Gas management systems and monitoring are permit requirements.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Landfill gas is explosive and asphyxiating and its methane emissions are regulated. Gas management systems and monitoring are permit requirements.

Frequently Asked Questions

Why is uncollected methane so significant?

Methane has a global warming potential around 28 times carbon dioxide. Even 25% escaping collection makes landfill a major emissions source, which is why gas capture is mandated at most modern sites.

What happens as a site ages?

Generation peaks shortly after closure and then declines exponentially. Engine capacity must be planned to be downsized or the gas upgraded or flared as output falls below viable levels.