Landfill Methane Calculator Formula
Understand the math behind the landfill methane calculator. Each variable explained with a worked example.
Formulas Used
Methane Emitted
methane_emitted = emitted_tonsCO2 Equivalent (GWP-100)
co2_equivalent = emitted_tons * 28CO2 Equivalent (GWP-20)
co2e_gwp20 = emitted_tons * 84Methane Collected
collected = total_methane_m3 * collection_pct / 100 * 0.000717Variables
| Variable | Description | Default |
|---|---|---|
organic_waste_tons | Annual Organic Waste(metric tons) | 100 |
methane_yield | Methane Yield(m3 CH4/ton) | 100 |
collection_pct | Methane Collection Efficiency(%) | 50 |
total_methane_m3 | Derived value= organic_waste_tons * methane_yield | calculated |
emitted_m3 | Derived value= total_methane_m3 * (1 - collection_pct / 100) | calculated |
emitted_tons | Derived value= emitted_m3 * 0.000717 | calculated |
How It Works
How to Calculate Landfill Methane Emissions
Organic waste in landfills decomposes anaerobically, producing methane.
Formula
Methane Generated = Waste (tons) * Yield (m3/ton)
Methane Emitted = Generated * (1 - Collection %)
CO2e = Methane * 28 (GWP-100)
The density of methane is approximately 0.000717 metric tons per m3 at standard conditions.
Worked Example
100 tons of organic waste with 100 m3/ton methane yield and 50% collection.
- 01Total methane: 100 * 100 = 10,000 m3
- 02Emitted: 10,000 * 50% = 5,000 m3
- 03Emitted in tons: 5,000 * 0.000717 = 3.6 metric tons CH4
- 04CO2 equivalent: 3.6 * 28 = 100 metric tons CO2e
Frequently Asked Questions
How much methane do landfills produce?
Landfills are the third-largest source of human-related methane in the US, producing about 15% of total methane emissions. Each ton of organic waste generates 50-150 m3 of methane over its lifetime.
Can landfill methane be captured?
Yes. Landfill gas collection systems capture 50-85% of methane. The gas can be flared (reducing climate impact) or used to generate electricity through landfill-gas-to-energy projects.
How does composting prevent methane?
Composting decomposes organic waste aerobically (with oxygen), producing CO2 instead of methane. Since methane is 28x more potent than CO2, composting drastically reduces the climate impact of organic waste.
Ready to run the numbers?
Open Landfill Methane Calculator