FERRISBURGH — When Erik Andrus began milling his own flour, the Ferrisburgh farmer and baker noticed a sharp spike in his electricity bill.
His mill — imported from Europe, and one of the most energy efficient models available — was running for 12 and sometimes 16 hours a day, grinding the wheat that would soon be turned into bread. The electricity bill at Boundbrook Farm and the Good Companion Bakery jumped as much as 50 percent.
“Since the goal of the farming enterprise is to farm in as carbon neutral a way as we can do, that’s always bothered me,” Andrus said. “I don’t want to depend on Vermont Yankee and Hydro-Québec to bring my product to market.”
So Andrus — a tinkerer with an interest in reviving old agricultural traditions — set about finding a solution. He’s putting that research into action with a $10,000 grant he recently received from the Northeast Sustainable Agriculture Research and Education organization, funding he’ll use to build a low-tech, low-cost windmill for generating electricity on the farm.
He hopes to prove that homemade turbines can provide a cheap, accessible alternative for farmers or landowners who want to generate renewable energy without making a hefty investment.
The project evolved after Andrus briefly looked into a commercial windmill, and realized the cost and size of those turbines just didn’t make sense on his 110-acre farm. The windmill would have cost $36,000, and even with state and federal incentives Andrus and his wife were looking at a $16,000 investment. That just didn’t make financial sense: Given the family’s electricity use, the windmill may have never paid for itself.
“We weren’t happy with that,” he said. “Did it mean the right thing to do is to do nothing?”
So Andrus began research other options. He considered hitching his horses to a treadmill to generate electricity, and looked into old-fashioned wind-powered mills — only to realize that the only models he could find were medieval.
“Using wind to perform tasks like milling flour is one of the oldest uses of wind power in the world,” Andrus said. “But small-scale milling operations have gone the way of the dinosaur. So too have the ways of powering them.”
That’s when Andrus learned about the Savonius rotor — a type of “vertical access” wind turbine designed by a Finn in the 1920s. Unlike modern wind turbines, the blades on the Savonius rotor turn around like a merry-go-round. Attached to the blades are cups that catch the wind.
Andrus connected with retired engineer Victor Gardy in Charlotte, and together the two mulled over a possible Savonius rotor wind turbine. The rotors aren’t popular in commercial use: It’s impossible to make them very large, high-tech or efficient. In fact, the Savonius rotors tend to be heavy and slow moving, and don’t produce as much wattage as commercial turbines.
But they’re cheap. And for Andrus’ purposes, it seemed like a perfect solution.
Gardy’s first analysis shows that the Savonius windmill could generate enough electricity to power the Andrus farm. The two have finished their design, and Andrus and Ferrisburgh resident Amos Baehr will build the turbine this summer. They’re hoping to modify a defunct silo on the farm as a platform for the windmill. The finished design, which includes a box-like frame for the turbine, will be six feet wide by six feet deep, and 12 feet tall.
Andrus estimates the actual cost of the materials to build the unit is less than $3,000; he’ll be using the rest of the grant to research the windmill’s capabilities, and produce and distribute a manual explaining how others can build their own turbine, too.
“Anybody who has basic carpentry skills, and we are talking basic, will be able to build one of these,” Andrus said.
Andrus is confident about the Savonius rotor’s capabilities. That said, very few have been used. The rotor was explored a bit in the 1970s, at the peak of the energy crisis, but interest waned after prices fell again.
The rotor also clearly doesn’t make sense for commercial wind development, but Andrus thinks it could work on a farm like his.
“I don’t think that this is the kind of thing that you’re going to see dotting the ridges on the Green Mountains as a commercial wind development project, but it could really deliver results that mean a lot to people on a small scale,” Andrus said. He thinks that’s particularly true for farms. “All farms use electricity, but yet there are no pragmatic solutions for alternative power generation when it comes to wind that make any sense to the average Northeastern farmer.
“It seems like there’s kind of a blind spot in the engineering community for the possibility of homegrown solutions actually making a difference,” he continued. “The reason I’m doing this is because I haven’t found anything in the alternative energy dialogue that speaks to me as a small-scale farmer.”
Reporter Kathryn Flagg is at email@example.com.