Currently, less than 10% of wastewater treatment systems in the United States produce biogas for beneficial use. Even though it remains an emerging strategy, organics to energy is a viable alternative solution for communities and industry to reduce waste, recover nutrients, and create an additional fuel source—while lowering treatment costs. Recently, broader application of the U.S. EPA Renewable Fuel Standard has expanded opportunities for the use of biogas as a renewable fuel.
Ten years ago, the wastewater treatment plant in Gresham, Oregon was the City’s biggest energy-consumer. Today, the plant produces the same amount of electricity as it consumes in a year, using biosolids from wastewater treatment and fats, oils and grease as well as solar energy to produce power while also reducing energy costs. As a result, the plant now exports excess energy back to the local utility. Organic matter from wastewater now fuels 92 percent of the Gresham plant’s power – right on site – using a process that turns sludge into biogas. The City has doubled its biogas production since 2012, when haulers started trucking in wastewater filled with fats, oils and grease from Portland-area restaurants and food service establishments.