Energy from methane gas is provided by the City of Memphis wastewater treatment facility, which produces a methane by-product that is co-fired with coal at TVA’s Allen Fossil Plant. The project provides 8 megawatts of power production.
Methane is produced when organic wastes decay. The wastewater plant’s lagoon was covered to capture the methane, which otherwise would have to be burned, or flared, in order to reduce the hazard arising from gas buildup.
small diagram of methane plant
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If methane is released directly into the atmosphere, it is a potent greenhouse gas. In fact, its global-warming potential is 21 times greater than that of carbon dioxide. Using it to generate energy encourages more efficient collection and thereby reduces emissions into the atmosphere. For this reason, energy recovery from methane, where economically viable, is of considerable benefit to the environment.
Besides diminishing global warming, the use of methane fuel eliminates the consumption of more than 20,000 tons of coal per year, reducing regional and local pollution. The project has been approved by the Center for Resource Solutions, the organization that accredits Green Power Switch.