Builder chosen for county’s 1st manure digester
By MATTHEW DeFOUR email@example.com 608-252-6144 | Posted: Sunday, November 8, 2009 11:00 pm | (12) Comments
Dane County’s first community manure digester, the first cooperative project of its kind in Wisconsin, will be built and operated by a Milwaukee-based company that plans to finance most of the project itself.
By letting Clear Horizons, in partnership with SCC Americas, a global developer of greenhouse gas emission reduction projects, operate the Waunakee community digester, the county is avoiding the financial risks and rewards.
"That was important to the farmers (who wanted) a separate company operating the digester," Dane County Executive Kathleen Falk said of the county’s decision. "We’ve chosen this model because Clear Horizons brings significant private dollars."
Clear Horizons plans to privately finance everything except a $3.3 million state earmark. The state included $6.6 million in its latest budget for the Waunakee digester and another being planned near Middleton. The county planned to borrow $1.4 million for the project, but now won’t have to spend anything to build the first digester.
Clear Horizons general manager Dan Nemke said construction is expected to cost about $11 million. After designs are finalized and a site is selected on one of three participating farms, the company expects to break ground in the spring and begin processing manure by the fall.
A manure digester is essentially a mini power plant that uses bacteria to convert cow manure into mostly methane gas, a fiber material and a liquid fertilizer. The methane is burned to generate electricity and the fiber can be used as cow bedding.
The Waunakee digester is expected to generate $2 million worth of electricity every year, and Clear Horizons plans to sell the fiber material.
Dane County’s 400 dairy farms and 50,000 dairy cows – a $700 million industry – produce more than 2 billion pounds of manure each year. Much of that is spread on fields in the winter and the resulting runoff into creeks and rivers has killed thousands of fish in the past.
Phosphorus from manure is also the biggest contributor to the algae pollution that turns the county’s lakes green every year.
The Waunakee digester will use advanced separation technology to remove much of the phosphorus.
"When successful, this is a model that can be replicated throughout Wisconsin, the upper Midwest and the nation," Falk said.
Manure digesters are expensive, making them almost impossible for smaller dairy farms to build and operate their own. "The county is undertaking a tremendous effort to get enough farms together to have the scale to make it economically viable," Nemke said.
Clear Horizons has built one other manure digester project, at the Crave Brothers farm in Waterloo. Falk, Gov. Jim Doyle and U.S. Secretary of Agriculture Tom Vilsack toured the farm last month.
The other finalist to build the digester, Sauk City-based Energies Direct, which works with German engineering firms, has built four other digesters, including one in Fond du Lac in 2004 that was the first manure digester in the United States.
It proposed a $9 million digester but didn’t offer as much private funding, Falk said.