Uneaten food prepared for Sunday’s Cleveland Browns’ football game at FirstEnergy Stadium will take on a second life as electric energy and fertilizer. The system will generate valuable products while diverting waste from landfills and reducing greenhouse gas emissions, officials say.
Before the game, state and federal officials showcased the stadium’s operation to collect waste food from kitchens and send it for treatment at a nearby anaerobic digester. Operated by Quasar Energy at Ohio State University, the anaerobic digester is a column-shaped building that processes organic wastes. Naturally occurring microbes essentially eat the material and produce a biogas, which can be burned to make electricity or power natural-gas vehicles. Remaining solids contain nutrients that can be used as fertilizer.
FirstEnergy Stadium’s food waste play
FirstEnergy Stadium installed a system called Grind2Energy, made by Emerson’s InSinkErator business. Like a household garbage disposal, the Grind2Energy machine grinds up food scraps and, with the addition of water, creates a slurry. Rather than send it into the sewers, though, FirstEnergy Stadium has installed large tanks to collect the slurry, which is then collected and transported by truck to Ohio State University’s Ohio Agricultural Research and Development Center.
The Browns estimate that over the course of the season, uneaten food generates 35 tons of waste. Quasar will add dairy cow manure and potentially other sources of organic waste to the slurry and put it all into the digester. Over the course of weeks, the waste breaks down and produces biogas, which can be siphoned off and burned in a generator for electricity and heat. In a landfill, that food waste quickly would decompose into methane, a potent greenhouse gas. FirstEnergy Stadium estimates that its system will reduce the equivalent of 28,000 pounds of CO2 emissions, and generate enough electricity to power a home for a year and half. The Browns project is part of the U.S. Department of Agriculture’s U.S. Food Waste Challenge, a program launched this year to increase organic waste recycling by sharing best practices among organizations.
Source: GreenBiz