|
AMSTERDAM, NETHERLANDS/ Studies have estimated that
converting manure from the 95 million animal units in the United States would
produce renewable energy equal to 8 billion gallons of gasoline, or 1% of the
total energy consumption in the nation.
Because more and more farmers and communities
are interested in generating renewable energy from farm waste, there is a
growing need for information on the economic feasibility and sustainability of
such programs.
Cow waste
Now, in a case study published in the Journal of Dairy
Science, researchers at the University of Vermont and the Central Vermont
Public Service Corporation (CVPS) confirm that it is technically feasible to
convert cow manure to electricity on farms, but the economic returns depend
highly on the base electricity price; the premium paid for converted energy;
financial supports from government and other agencies; and the ability to sell
byproducts of the methane generation.
The CVPS Cow Power program assists farms in planning and
installing anaerobic digesters and generators to convert cow manure into
electricity, and markets the resulting power to its customers.
Dairy farms apply for grants from CVPS, government agencies,
and other organizations, and draw on their own funds and loans from local banks
to install the necessary equipment. CVPS customers voluntarily participate in
and agree to pay a premium of $0.04 per kWh for a proportion or all of their
electricity use.
Funding must payback
“With more than 4,600 CVPS electricity customers voluntarily
paying $470,000 in premiums per year, the Cow Power program represents a
successful and locally sourced renewable energy project with many economic and
environmental benefits,” says lead author Dr. Qingbin Wang.
Wang, a professor in the Department of Community Development
and Applied Economics, of the University of Vermont, found that because of the
huge initial investment of about $2 million for equipment per farm, grants and
subsidies from government agencies have been necessary; without them, few dairy
farms are able to fund such a system.
The price farmers received for their electricity and revenue
from byproducts of the system were also critically important.
Reverting processes
Scenario analysis presented in the case study also suggests
that relatively small changes in the premium price can have a significant
impact on the cash flow of an average operation. Also, waste heat from biogas
combustion can be captured and used on the farm and byproducts from the digester,
in the form of animal bedding and compost, contributed significantly to the
cash flow of farms – up to 26% of the total revenues in 2008.
Dr. Wang concludes, “For any community
interested in a locally sourced renewable energy project like the CVPS Cow
Power Program, the strong commitment and collaboration of utilities, dairy
farmers, electric customers, and government agencies at the state and local
level is essential.”
|
