Green Wombat

I look at the face of renewable energy and it looks back at me with big brown eyes and says, "Moo."

Meet the cows of Blue Spruce Farm in Bridport, Vermont. Each of the 2,000 cows produces not only milk but 200 watts of power a day. Cow manure is fed into a anaerobic digester on the farm, where bacteria strip away pathogens and produce methane gas. The gas powers a generator that produces electricity, which is fed into the grid operated by Central Central Public Service, the local utility. Cows are king in Vermont and about 75 percent of the state’s agricultural revenue come from dairies. But cow poop releases methane, a particularly powerful greenhouse gas, and creates a huge waste management headache for dairies like Blue Spruce Farm, owned by the Audets family.  "We weren’t thinking of global warming when we dd this, we needed to do deal with the waste problem," says Marie Audets, a no-nonsense woman who has worked on farms most of her life, as she showed me and a group of environmental journalists around Blue Spruce Farm.

Vermont is not the only state experimenting with cow power – California is home to some 2 million cows and this month Pacific Gas & Electric signed a deal to buy methane gas from Microgy, a company that will build four digesters on Big Ag dairy farms. What’s different about Vermont cow power is that it’s connecting consumers to family farms that are struggling to cut costs as milk prices fall. CVPS customers who sign up for cow power pay a 4 cent kilowatt-hour premium, or about $5 to $20 more a month for their bovine-sourced electricity.

The Audets financed the methane digester shown above. It captures the methane that would be released into the atmosphere and turns it into electricity that Blue Spruce sells
to CVPS, effectively reducing the farm’s net power costs to zero. The digester’s byproduct is sterilized manure (shown at right), which is used as cow bedding instead of increasingly expensive sawdust. That saves the dairy as much as $100,000 annually. Cow power is another example of what’s good for the environment is often also good for the bottom line. The effort got a big boost Thursday when a local environmental liberal arts school, Green Mountain College, agreed to power its campus with cows. CVPS is working with four other farms to install methane digesters.