Chapter 2: Capturing the Power of Wastewater Methane Wastewater treatment plants account for an average of 30 to 40 percent of a city’s total electricity use.41 Generating power from methane for on-site use provides advantages to energy-intensive wastewater treatment plants. Captured methane gas powers one-third of Washington DC’s Blue Plains Treatment Plant, the largest advanced wastewater treatment system in the world.42 The use of methane decreases Blue Plain’s energy bill and lowers the total electricity demand on the city. Methane reuse makes wastewater plants, considered by the U.S. Department of Homeland Security as “critical infrastructure,” more resilient to shocks and stresses by diversifying power sources and allowing them to function partially off-grid.43 Wastewater treatment plants in China can follow the lead of Blue Plains by capturing methane produced during wastewater treatment and using it for productive purposes, such as electricity, heat, and vehicle fuel.
THE FORGOTTEN GREENHOUSE GAS Methane gas causes severe damage to the Earth’s atmosphere. While methane lasts only 12 years in the atmosphere,44 its total global warming potential is 28 to 36 times greater than that of carbon dioxide.45 As the world’s largest methane emitter, China accounts for nearly 20 percent of global methane production, equal to the methane produced
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Sludge digestion installation on a waste water plant. Here is methane produced and used for the energy supply for the plant
