ORONO, Maine — One Saturday afternoon a few years ago, David Labrecque was driving through downtown when he looked up and saw a large banner for Orono’s Festival Day hanging across Main Street. The sign was flapping in the wind.
“This banner was just flipping back and forth,” Labrecque said during a recent interview in his office in the University of Maine’s Aubert Hall. “I thought, wow, there’s a lot of energy there. How could we do that?”
It wasn’t the first time Labrecque had been inspired to think about wind energy. But the sight of the banner that windblown day gave him some inspiration for his latest effort.
Labrecque recently founded Flexor Energy Co., through which he is selling an invention he calls the Aeroflexor, a device that harnesses wind energy and turns it into power. Right now, the entire device is just a few feet high and churns out just enough energy to power a flashlight.
Labrecque’s vision for his invention is one of large-scale Aeroflexors stretched across points of land or mounted somehow in deep ocean waters, capturing big swaths of wind to produce enough power to benefit larger populations.
Labrecque has received a provisional U.S. patent for Aeroflexor and about $25,000 in seed grants from the Maine Technology Institute for continued research and development of the technology. Flexor Energy also is working on a Hydroflexor, which can be used to capture water or tidal power.
Aeroflexor is a revolution in wind power, Labrecque said, in which a vertical wing-shaped piece of material in either a 3- or 5-foot length is attached to an arm at the top and a tether at the bottom.
Energy is generated when the material flexes as it flaps in the wind and the tether pumps up and down, like a piston in a car. The energy from the flexing wing can be used to drive a linear generator to put out about 3 watts of energy.
The device needs about 8 mph of wind in order to start.
In designing Aeroflexor, Labrecque considered some of the traditional types of wind power generators. While each does the job, the well-known variations also have drawbacks.
The windmill-like turbines springing up all over Maine lately are expensive because of their size, weight and transportation and maintenance issues.
A Savonius turbine, another type of wind power generator, uses drag force, Labrecque said, and not lift force, which is more efficient than drag force.
A third type of turbine, called a Darrieus, needs a motor in order to function because it doesn’t self-start.
And when such systems suffer a brake failure, they fail spectacularly — just check out the videos on YouTube.
Aeroflexor, Labrecque said, has fewer expensive parts, uses lift force and self-starts. Should a large-scale Aeroflexor fail, it would mean fabric rather than heavy turbine parts falling to the ground.
Labrecque and a crew of UMaine undergraduate and graduate students in business, engineering and physics are unsure about the range and limits of the Aeroflexor, and are taking its development slowly.
“This is unique,” said Aaron Tanenbaum, a Presque Isle native and UM senior studying physics. “It’s never been done.”
Because the Aeroflexor is still relatively rudimentary in its construction — any Mylar balloon from a gift shop or discount store will do to make it run — Labrecque said he is targeting customers who like to tinker.
“We’re still at the hobby stage,” he said. “It’s like Apple computer. When they first started, they were putting out these little hobby computers. Then the hobbyists would play with them and tell them what was wrong. That’s where we are.”
Aeroflexor also could be used, Labrecque added, as a device to teach students about the basic principles of wind power. He presented the device at UM’s high school wind blade design competition in May.
At a limited-time price of $29.99 for the Aeroflexor kit, which includes everything needed to build a 5-foot version of the device, Labrecque acknowledged Aeroflexor isn’t exactly cost-effective yet for the general public.
“On a cost-per-watt basis, you wouldn’t do this,” he said. “It depends on the application. The fact of the matter is, the really small wind systems are not cost-effective. You have to get to a large scale where you start seeing a good return. You run this between two hills, get the same scale as the big guys, it would probably cost less than the big turbines.”
Labrecque, who is originally from Waterville and holds two engineering physics degrees from UM, has experimented over the years with different methods for harnessing wind energy. Thirty years ago, he said, he mounted on his roof a Savonius turbine. About five years ago, he came up with another idea using high-altitude wind turbines.
He applied for a grant for the design but was turned down. Looking back, he said, the rejection was a good thing.
“That drove me towards something more ground-based and more practical,” Labrecque said.
That helped him hit upon Aeroflexor.
In its current small, rudimentary state, Aeroflexor could be useful for a person on a camping trip without electricity, or for pumping water. Labrecque said he plans to contact groups such as Engineers Without Borders that look for inexpensive, portable energy solutions for Third World nations.
“Of course, expense is everything, and this is extremely low-cost to build,” he said.
There is plenty of work left to do for Labrecque and his students before Aeroflexor grows bigger and gains a wider audience. He hopes to have a more professional product next year.
“I’m actually concerned with really high winds,” he said. “We haven’t addressed that issue yet as far as if [the wind] gets to 30 mph, can [Aeoflexor] handle it, and how do we shut it down. That’s one of the things on our list of things to do. We’re making pretty good progress with it.”