VEC Converts Food – Waste to Energy with Biodigester Project

Collaboration Brings Anaerobic Biodigester to Vermont Technical College

Rising energy costs, finite supplies of fossil fuels and concerns about energy security have increased America’s interest in renewable energy technologies. While some regions have access to wind power, abundant solar energy, hydropower or geothermal resources, all of our communities produce wastes that can be used to generate heat and electricity.

For example, food scraps and other organic wastes are typically viewed as a costly liability to communities and businesses. Organic wastes are typically landfilled, a process with significant economic and environmental costs. However, organic wastes can also be used to generate renewable energy and as a source of nutrients and soil amendments for agricultural use. In Europe, organic wastes and energy crops are used as feedstock for anaerobic digestion (AD) an environmentally friendly waste-to-energy technology. This biological process produces biogas that can be combusted to produce energy, both electricity and heat. Feedstock nutrients are not diminished by digestion and can be used as agricultural fertilizer.

With the support of U.S. Senator Patrick Leahy and funding from the U.S. Department of Energy, the Vermont Agency of Agriculture, Food and Markets, the Clean Energy Development Fund, and the Vermont Department of Public Service, VEC and a group of partners worked together to bring this renewable energy technology to Vermont. With assistance from VEC and the Vermont Sustainable Jobs Fund, the Central Vermont Solid Waste Management District (CVSWMD) and Vermont Technical College completed a feasibility study.

Feasibility work on the CVRBF (Central Vermont Recovered Biomass Facility) suggested that a daily feedstock mixture of 10 tons of dairy manure and 15 tons of food scraps could power a 250 kWh co-gen plant capable of producing up to 2 million kWh annually and displacing 25,000 to 50,000 gallons of heating fuel each year. Further, the study suggests that number of similar facilities could be constructed across Vermont to manage organic wastes and contribute to renewable energy production. This project, the CVBRF AD facility was granted a spot in Vermont’s electricity feed-in-tariff queue.

Vermont Tech’s Community Anaerobic Digester is a living laboratory that adds to Vermont’s renewable energy infrastructure and organics management.  Made possible by the team of partners and funding from the US Department of Energy, the Community Anaerobic Digester project culminated into a comprehensive report after its first year of operation. Using the findings of this report and the ongoing primary data produced at the digester, anaerobic digesters can be replicated by colleges and municipalities nationwide to keep excess nutrients out of watersheds and food residuals out of landfills while generating renewable energy. Download the final report here.