Getting Mileage Out of Manure

Dairy farmer, researchers look for ways to power cars with bio-gas from cattle

23 February 2010

Dairy owner Darryl Vander Haak turns cow manure into 'bio-gas' which burns like natural gas in a small electric power plant right on his farm.

Five years ago, dairy farmer Darryl Vander Haak flipped the switch on the first electric generator in Washington State powered by manure. The facility is officially known as a methane digester.

Manure from about 1,000 cows goes in one end and then, controlled decomposition yields methane gas at the other.

The raw material for the digester comes from livestock waste that might otherwise end up in a smelly manure lagoon on the farm. This so-called 'bio-gas' is burned like natural gas in a small electric power plant right on Vander Haak's farm. The dairyman sells his excess power to the local electric utility.

Methane digesters are increasing in number, especially in Europe. But there's an important difference between Europe and America: electricity in the U.S. is relatively cheap. Dairyman Vander Haak says his energy sales have not been profitable. "The Northwest has too much [cheap] hydropower to compete with," he points out, adding that he's been looking for alternative markets. "It would be easier to compete with the gas companies, I guess."

Cow power to horsepower

That's why Vander Haak was open-minded when the Vehicle Research Institute at Western Washington University, just down the road from his dairy, called with an offer to truck away some of his methane.