Generators convert methane from cow manure into electricity. |
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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.”
Ralph Dannheisser
/ USINFO Staff Writer
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