Vt. Dairy Farmers Use Manure for Energy

Associated Press ^ | June 30, 2006 | DAVID GRAM

[decimon]

Vt. Dairy Farmers Use Manure for Energy By DAVID GRAM (Associated Press Writer)

From Associated Press June 30, 2006 7:07 AM EDT

BRIDPORT, Vt. - The cows at the Audet family's Blue Spruce Farm make nearly 9,000 gallons of milk a day - and about 35,000 gallons of manure. It's long been the milk that pays, but now the Audets have figured out how to make the manure pay as well. They're using it - actually, the methane that comes from it - to generate electricity.

With the help of their power company, Central Vermont Public Service Corp., the Audets have devised a way to extract the methane from the manure and pipe it to a generator.

They make enough electricity to power 300 to 400 average Vermont homes. It's renewable energy, and they're not the only ones interested in it. Four other Vermont farms now have similar projects in the planning or early construction stages, power company officials said.

The Audets "deserve to be congratulated. They're the pioneers among Vermont farmers," said Dave Dunn, a senior energy consultant with CVPS who worked with them on the cow power project.

Elsewhere in the country, farmers are using similar technology to make energy, said Corey Brickl, project manager with Wisconsin-based GHD Inc., which built a device that the Audets use to harvest the methane.

One in Washington uses tomato waste from a salsa factory and waste from a fish stick plant as fuel, Brickl said.

For the Audets, the electricity has created an important new income stream at a time when low wholesale milk prices have squeezed their margin. The utility pays 95 percent of the going New England wholesale power price for electricity from the Audets' generator.

In addition, the utility charges customers willing to pay it a 4-cents-per-kilowatt-hour premium for renewable energy and then turns the money over to the Audets. So far, more than 3,000 CVPS customers have signed up to pay the premium to support the renewable energy effort.

The bottom line is more than $120,000 a year from electricity sales. When they add in other energy savings enabled by the project, the Audets expect their $1.2 million investment in project equipment to pay for itself in about seven years.

The program has piqued interest.

Marie Audet, who describes herself as wife, bookkeeper, and milker, has become a tour guide, showing people from the United States and a handful of other countries around the farm's cow power operation.

Managing the hundreds of milking Holsteins - as well as young stock - is a high-tech operation.

In their stalls, cows munch contentedly on a mix of hay and silage while they make an occasional contribution of fuel for the Audets' power plant. An "alley scraper," which looks like a big squeegee on wheels, comes by to push their manure down the row and through grates to a conveyor belt below.

From there, the manure goes to an anaerobic - meaning oxygen-free - digester, a 100-foot-by-70-foot structure similar to a covered swimming pool built by Brickl's company. The manure spends 20 or 21 days in the digester, being pushed slowly from one end to other as more is added.

Three products result: a liquid that contains enough nutrients that it can be used as fertilizer for the farm's feed crops; a dry, odor-free, fluffy brown substance that is used as bedding for the cows and some of which goes to a local firm that bags and sells it as fertilizer on the home-and-garden market; and methane.

The methane is piped into an adjacent shed that contains a big Caterpillar engine that powers the 200-kilowatt generator.

Audet said the farm was saving the $1,200 a week it formerly spent on sawdust bedding for the cows, as well as some of the cost of heating the milking barn. A study by agricultural scientists from the University of Vermont found that the bedding produced from the manure was better than the sawdust. "Wood harbors a lot of bacteria," she said.

With the success of the 200-kW unit, the Audets are expanding by adding a new, 75-kilowatt hour generator. And Audet said she's even grown to like giving the tours.

"It's bringing a lot of people to the farm who are normally very removed from food producers," she said.

---

On the Net:

Central Vermont Public Service: http://www.cvps.com

[Uncledave]

Renewable Energy Ping

Please Freep Mail me if you'd like on/off

[Calpernia]

Big bump to Vermont!


http://www.breederville.com/auction/forumtopic-67-1.html
Vt. Dairy Farm Harnesses Power of Cow Pies

http://www.breederville.com/auction/forumtopic-73-1.html
Farm Premises ID & NAIS Dead in VT

[Calpernia]

bttt

[Pete from Shawnee Mission]

My guess is that you can use the heat from the methane digester to heat a barn, a house, greenhouse, or something like that. You can use the product, the night soil for fertilizer, or, compress it and burn it (not sure about this) and extract more heat.

My father had a cold frame that he would use to start seedlings. In early March he would dig a pit about 2 feet deep, dump in a foot of manure cover it with a foot of topsoil and plant. The heat from the composting manure would provide heat for the seedlings on cold nights.

When horses were still a primary form of transportation, there were some french farms that would grow through the winter. They would collect the manure in rows, cover with topsoil, and plant their crop, usually lettuce or radishes, some crop that didn't take 120 days to grow. Bell jars covered the crop, and at night they rolled out a canvas covering to retain the heat. You could only do this for specialty crops, but it was still fresh produce in the winter.

Again, these are curiosities. But you use what you have, and what your circumstances dictate. I doubt that we will go back to manure as direct heat source anytime soon, but we may be able to use it to create methane, which is a bit more transportable and acceptable heat source.

[decimon]

From the second link:

"The VT AoA is one 800 lb guerilla that just learned it can't sit anywhere it pleases."

If there's an 800 pound guer(r)illa and an 800 pound gorilla, which gets the seat?

[Calpernia]

If something is 800lbs, I would opt to get out of it's way and let it sit.

[ClaireSolt]

Since I was a kid, Milwaukee solid waste has been marketed as fertilizer under the label Milorganite.