21 February 2008
“Cow Power” Program Converts Animal Waste into Electricity
Vermont utility’s approach aims to cut pollution, boost farm income
Washington -- “You can’t make a silk purse out of a sow’s ear,” an old saying has it. But a Vermont utility is accomplishing an equally remarkable transformation, turning cow manure into electric power -- and in the process both helping to reduce pollution and giving an economic boost to hard-pressed dairy farmers.
Launched by Central Vermont Public Service (CVPS) in 2005, the “Cow Power” program relies on the willingness of thousands of customers -- individuals and businesses -- to pay a bit extra for their electricity if that means expanding renewable power generation and helping their farmer neighbors.
Both federal and state government have pitched in as well, providing participating farmers with grants and loans to help with the heavy startup costs of installing the equipment needed to convert methane from cow manure into electricity.
The process used is a relatively simple one: manure and other agricultural waste is held in underground concrete tanks and kept at 101 degrees Fahrenheit (about 38 degrees Celsius) -- the temperature of a cow’s stomach.
Bacteria digest the stored material, creating methane even as they kill pathogens and weed seeds. The methane, some 20 times more harmful than carbon dioxide in trapping heat in the atmosphere, fuels an engine-generator.
CVPS customers can choose to get all, half or a quarter of their electricity through Cow Power and pay a 4 cents per kilowatt-hour surcharge. That amounts to about $20 a month for the average customer, company officials say. The 4 cents premium is funneled to participating farmer-producers, who also receive 95 percent of the market price for energy they generate.
CVPS scored a coup in December 2007, when Power magazine named Cow Power one of five top renewable energy undertakings worldwide.
The magazine cited the program’s extensive environmental benefits, including improved air and water quality, reduced manure odor and reduced greenhouse gas emissions. And it pointed out the benefits for participating farmers, “chief among them a new, steady income stream that offsets fluctuations in milk prices.”
In addition, Power said, farmers can save on fuel purchases by using excess heat from the engine-generator to heat water and provide space heating. And, since the digestion process kills pathogens, residual solids can replace the sawdust usually used as bedding for the animals.
CVPS spokesman Steve Costello says that more than 4,600 customers have signed up for the program, “giving farm owners the confidence to become Cow Power farms.”
Still, only five farms have joined to date -- four currently online and one more in the planning process -- likely reflecting caution prompted by the sizable up-front costs of installing the needed equipment.
Mark Sinclair, deputy director of Clean Energy States Alliance (CESA), a national renewable energy nonprofit based in Vermont, said, “The technology is still relatively new, it’s very expensive, and payback takes eight to 10 years.”
With herds totaling some 5,200 milking cows, the farms enrolled produce an estimated 9.4 million kilowatt-hours a year, CVPS says.
The limited farm participation thus far means that demand exceeds supply, a situation which Dave Dunn, CVPS Cow Power coordinator, sees as “good news.” Says Dunn, “People are signing up at an accelerated rate, and we’re really leading the pack and other places are starting to notice.”
Though manure-to-energy conversion is not a new idea, Dunn says, the Vermont utility’s approach is unique in that “we’ve created a new business model. We found a way to connect … the supply side that’s being produced by the farmers with the demand side. Nobody believed that customers would pay an extra 4 cents for every kilowatt-hour to select renewable energy.”
But they are doing so “to select renewable energy that’s been produced by a neighbor,” he says.
To mitigate the startup costs, the U.S. Department of Agriculture issues loans and grants under a section of the 2002 farm bill designed to support renewable energy systems. The state’s agriculture agency and energy office provide modest supplementary subsidies and low-interest loans.
As important, CESA’s Sinclair says, the state has created a streamlined regulatory approval process “so these farmers don’t have to spend thousands of dollars on lawyers to get a permit from the state to site these projects.”
Sinclair terms Cow Power “a green pricing program that’s unique in the country.” But he speculates that the surcharge to consumers, now voluntary, ultimately will have to be made mandatory to give such programs maximum impact. That is the approach used widely in Germany, he says, and “some states are also thinking about that sort of structure.”
Jason Bregman, an environmental planner with a practice in Vermont, also sees Cow Power as a harbinger of things to come.
Bregman, who co-authored a paper on “Infrastructure and Community” produced by Environmental Defense, a nonprofit environmental advocacy group, sees the program as “just the beginning in the mining of organic waste for local fuel sources.
“The next generation of renewable energy systems will seek out organic matter in municipal, commercial and agricultural waste streams as a relatively easy source of fuel to obtain and process energy,” he says.
Amanda St. Pierre, co-owner of the participating Pleasant Valley Farm, lauds Cow Power as a means of diversifying income. Speaking on a CVPS-produced video promoting the program, she expresses the sow’s-ear-to-silk-purse equation from the farmer’s point of view: With milk prices volatile, she concludes, “Even if we can’t get money for our milk, we’re going to get money for the manure.”
