Anaerobic Digestion: Turning One Man’s Trash Into Another Man’s Treasure January 20, 2009 Dr. Catherine Keske Dr. Sybil Sharvelle

Recovering Manure to Produce Energy Benefits of Anaerobic Digesters How Digesters Work Trends and Feasibility Economic Issues How to Get Involved or Learn More Questions

Benefits of Anaerobic Digesters Environmental Production –Soil management –Manure management –Biogas production Reduces environmental pollution –Water –Green house gases –Ammonia Economic and Social On-farm energy generation (avoid electricity purchases) May sell energy to utilities Savings on bedding Sale of composted solids Carbon credits available Renewable energy certificates Odor control

Anaerobic Digestion: How It Works High BOD Waste Organics  Acids Acids  CH 4 High Nutrient Low Odor Waste Anaerobic Environment Cogeneration Hot Water CH 4 Green Power

ADM Soybean Processing Biodiesel Plant Anaerobic Digester Frito Lay Hot Soybean Oil Cold Soybean Oil Hog Waste Food Waste Green Power Model Project: Quadra Project in Indiana WE Can Do This in Colorado Too!

Waste Suitablility Low solids content, < 14% solids Low inorganic content –Soil –Rocks Higher organic content, more energy content

Colorado – Cold Climate Average Annual Minimum Temperature

Covered Lagoon – Not an Option

Colorado – Dry Climate Average Annual Precipitation In Colorado Need to Find Nearby Source of Wastewater or Add Groundwater to Waste

Successful Digester at Dairy in Montana

Alternative Design - Two Stage Leachate Collection Low Moisture Manure and Other Waste Organics High Organic Leachate Anaerobic Digester Methane Gas

Costs of Anaerobic Digesters Cost of the digester: Approximately $1 million Average life: 15 yrs. (Range: 10-20) Cost of the solids separator: Approximately $75,000 **Key to raising profitability** Opportunity cost Cost of your next best alternative

Are Digesters Profitable? “Yes…” Several models show profitability –Measured in cash flows associated with the investment Critical to use a solids separator –Use the solids as a co-product –Bedding is the most economic use Larger herds lead to economies of scale Key element to profitability: Energy prices

“…But…Will a Digester Work for My Operation?” Greater than 500 head (more than 1,000 head preferred) Requires steady flow of manure (CAFOs) Climate matters – the warmer the better Must be able to use the biogas “Community” digesters are an option –Pipelines transport waste to central site –Could consider other facilities (e.g. food processing)

“Yes, But…” Economic Considerations Majority of studies conducted in the East Profitability relies on carbon credits –$2 per metric ton of CO 2 “Net positive gain” may include a net gain to the environment (not necessarily a net gain to the farmer/rancher) Profitability critically depends upon energy prices

Want to Learn More? Contact Us! Institute for Livestock and the Environment: USDA Producer Workshop 2/19/09 York, Nebraska AgStar: Colorado Governor’s Energy Office: Sponsoring feasibility studies

Questions?