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The Effects of Global Warming on Landfills

Global warming refers to the continued rise in temperature of the Earth's surface, which many researchers believe is caused by the release of greenhouse gases created by human activity. The gases produced by this activity that are of concern include carbon dioxide, methane, nitrous oxide and a group called fluorinated gases. A landfill is usually considered a source of pollution because of the disposal of thousands of tons of waste, often leaking toxins into the soil and causing groundwater contamination. But landfills may also be a source to help minimize global warming.

Methane Gas
- According to the U.S. Environmental Protection Agency (EPA), the third largest human activity-related producer of methane gas in the United States is landfills, with 200 to 400 cubic meters of gas made for every ton of waste. Methane is up to 21 more times destructive as a greenhouse gas than carbon dioxide is. Many times, fires that break out at landfills are the result of the buildup of methane gas. But methane gas can also be used to create power, acting as a substitute for some of the coal and water used for electricity generation.
Collection of Methane
- Methane is the primary element in natural gas. The methane gas generated by the decaying waste of the landfill is collected by drilling wells into the ground and then collecting the gas by sucking it into pipes. The gas is fed into the natural gas pipeline system. The methane is then extracted from the gas and used to power electricity-producing plants.
Benefits of Methane
- When coal is burned to generate electricity, nitrous oxide, another greenhouse gas, is released into the atmosphere. Nitrous oxide also causes smog. Methane gas from the landfill used to generate power releases very little nitrous oxide. Capturing methane gas and using it for an energy source not only stops the damage escaped methane causes to the atmosphere, but also drastically reduces damage from nitrous oxide. Another benefit of gas-burning power plants is that they are smaller than coal-burning plants, and any pollution emissions to local water sources are also small.
EPA Calculations
- The EPA calculates the benefit of landfill gases two different ways. The first is by the direct reduction of methane gases being released into the environment. The second calculation involves adding up all of the potential carbon emissions from fossil fuels (such as coal) that the use of methane gas from landfills replaces. Using the EPA's calculations, methane gas produced daily from 4.2 million cubic feet of landfill is equivalent to taking 66,000 vehicles off the road.

Nature