Green Mountain Power customers across Vermont can now support a form of renewable energy produced by over 10,000 Vermont dairy cows, thanks to a new ruling by the Vermont Public Service Board approving the expansion of the GMP Cow Power Program from the limited territory previously served by CVPS to the entire GMP service territory.
Cow Power was first offered to customers in 2004, as a way to offer new, local renewable energy choices. The GMP Cow Power program currently includes 12 farms, and generates 16 million kWh per year — enough to completely power 2,200 average Vermont homes.
To produce Cow Power, farmers feed cow manure into an on-site anaerobic digester. Naturally occurring microbes in the digester convert the waste into several useful byproducts, one of which is methane gas. The methane fuels an engine that drives an electric generator. Heat generated from this process is repurposed to keep the digester warm, and can offset fuel purchases on the farm for hot water and space heating. The energy generated is fed into the GMP electrical system for distribution to customers.
The coarse plant fibers left over are processed through a mechanical separator. These odorless solids can be used to replace sawdust or sand as bedding for the animals. Solids not used for bedding may be further processed and sold as a garden soil. The liquid portion is an enhanced fertilizer used to grow crops to feed the cows.
Vermont dairy farms currently producing GMP Cow Power include Blue Spruce Farm, Gervais Family Farm, Green Mountain Dairy, Chaput Family Farms, Montagne Farm, Dubois Farm, Berkshire Pleasant Valley Farm, Monument Farms, Maxwell’s Neighborhood Farm, Kane’s Scenic River Farm, Maplehurst Farm, and Four Hills Farm.
Customers can choose to buy 25 percent, 50 percent, or 100 percent of their energy from Cow Power, and pay an extra four cents per kilowatt hour premium. If an average Vermont household using 600 kwh a month decided to get 25 percent of their energy from GMP Cow Power, they would pay an extra $6 per month.
Green Mountain Power generates, transmits, distributes and sells electricity in the state of Vermont. The company serves more than 250,000 customers.