Twin Birch Farm is a second generation farm that was bought at auction in 1960 and started out with 120 cows. In 1999 it doubled in size, and a few years later the farm began experiencing neighbor problems with manure storage. That is when they began looking into the option of a horizontal plug flow anaerobic digester.
In addition to trying to avoid odor issues associated with long- term manure storage, other reasons the farm was intrigued by this option was for energy savings, and to prevent the environmental and soil compaction impacts of daily manure spreading.
Some of the challenges the farm faced when operating their AD system effectively and utilizing the generated biogas include problems with the initial AD system design, the use of a hardtop to contain biogas, the heating system, and the efficient use of microturbines. Additionally, the farm has had to handle the constant challenge of biogas- induced corrosion throughout the digester operation.
IFES Number: 48
Type of Firm: Farm
Main Products: Dairy; compost
Size of Firm: 1175 milking cows; 2700 total acres
Ownership Type: Private
Energy System Components: Anaerobic digester
Operational Status: Operational
Year Installed: 2003
Energy Feedstock: Manure from 1,900 cows; Milkhouse waste
Energy Produced: Biogas production: 100,000 cu_ft/day
Energy Uses: Electricity; Boiler/Furnace fuel
Fossil Energy Inputs Replaced: Fuel oil replaced by captured waste heat off GenSet
New co-products: Compost
Money Saved: $10k savings/year on heating oil
TCO2 Eq Avoided: 2,776 CO2E/yr