Just like manure, other types of organic waste emit methane as they decompose—or rot—in the landfill. Landfills can collect and treat the methane, and then sell it as a commercial fuel, or they can burn it to generate steam and electricity. Today, there are more than 620 gas energy landfill projects operating in the United States.
(Source: EPA’s Landfill Methane Outreach Program, Sept. 2018)