Jewish World Review March 15, 2001 / 20 Adar, 5761
http://www.jewishworldreview.com -- FARMER Dennis Haubenschild is testing a new source of power: cows.
At his family's dairy near Princeton, Minn., Haubenschild is converting manure to electricity and simultaneously reducing odor in an experiment he hopes will improve air quality near feedlots.
In January, the coldest month of the year, the Haubenschild farm produced enough methane from its 850 cows to power the dairy operation and 78 homes.
The farm - the only one in Minnesota with a fully operational anaerobic digester - demonstrates how farmers can help the state become more energy self-reliant, Haubenschild said.
Manure is heated to 95 to 105 degrees to speed up its digestion by bacteria. The process produces "biogas" that contains 55 to 70 percent methane.
Alternative energy isn't the only benefit. Haubenschild and others say the digester process greatly reduces the manure's stink, greenhouse gases and pathogens, while boosting the fertilizing value of manure.
State officials are looking for a hog farm where the same kind of experiment can be conducted to biologically treat manure while improving air, soil and water quality near feedlots.
"In farming, you have to work with Mother Nature," Haubenschild said. "If you're not an environmentalist, you're not going to be successful."
He recently testified in support of a state bill to create a $10 million revolving loan fund for manure-processing and odor-control projects. Under the legislation a farmer could seek an interest-free loan for up to $200,000.
Haubenschild testified that his digester process enabled him to save 35 tons of coal and 1,200 gallons of propane that he otherwise would have used in January. During spring planting, he won't have to use 34 gallons of propane or natural gas per acre to make anhydrous ammonia, he said.
Here's how the system work:
Every day, about 20,000 gallons of manure are pumped to collection flumes beneath two barns and then into the digester, a 400,000-gallon tank that looks like a small, oblong Metrodome.
The anaerobic digestion of the manure is accelerated by heating it for 20 days before it moves into a lagoon for later application as field fertilizer.
Before the Haubenschilds began using the digester in 1999, the smell of freshly mixed and spread manure would drift two or three miles and last four days. Now, a much milder smell from the digested effluent disappears overnight after spreading, said Marsha Haubenschild. She and husband Dennis own the 1,000-acre farm with their sons, Bryan and Tom.
In the silvery-colored digester, biogas builds up. It's routed to an engine and generator, which convert it to electricity and hot water. The electricity flows to a transformer and the water heats the digester and barn floors.
A third of the electricity returns to the farm to power the milking parlor and other operations. Two-thirds is sold to East Central Energy, a cooperative serving 43,000 customers in east-central Minnesota. In January, the Haubenschilds earned $4,380 selling electricity.
Electric cooperatives are excited about the project, which is exceeding expectations, said Henry Fischer of East Central Energy. He serves on an advisory task force that prepared a report on the digester project.
"It's an excellent example of sustainable agriculture," Fischer said. "By using the digester, the Haubenschilds not only end up with high-quality compost - a liquid slurry that they can use for fertilizer - but from an environmental perspective, it eliminates all the odors associated with the fertilizer. The electricity is a bonus."
Everything at the farm is designed for the cows' comfort, Tom Haubenschild said. They are milked three times a day, fed constantly and bedded on 5-inch mattresses covered with rubber liners and recycled newspaper. Keeping each 1,400-pound Holstein contented leads to high production, the Haubenschilds say.
"That cow is producing our milk and our electricity and enough manure to do it all over again," Dennis Haubenschild said. "That's a real conversion."
He began researching digesters 25 years ago while studying microbiology in college. After years of trying, he received state and federal financing for the $355,000 construction of the digester and generator system. It began operating in September 1999.
The Haubenschilds now have 30 employees working three shifts,
running electric milkers and maintaining the farm. Dennis
Haubenschild figures the system will pay for itself in five
Joy Powell writes for Minneapolis-St. Paul Star Tribune. Comment by clicking here.