Forget the offshore wind farms proposed by Deepwater Wind and Cape Wind that local officials hope will spur a niche industry of manufacturing turbines.
Instead, Matt Dunham is looking at smaller wind projects as possible revenue generators for his carbon-fiber fabrication business.
Dunham, owner of Clear Carbon & Components Inc. in Bristol, recently constructed the specialized blades and other parts for a vertical-axis wind turbine that a Massachusetts green-energy company hopes will revolutionize the wind power industry.
“The idea is not to build just one, but to build multiple turbines,” Dunham said.
The prototype, financed by Cambridge, Mass.-based Eastern Wind Power Inc., is unlike a conventional wind turbine that turns like an airplane prop.
Eastern Wind Power’s 20-foot-high turbine spins in a vertical cylindrical pattern, allowing for them to be placed closer together, among other things, perfect for installment atop buildings.
At least that’s the plan for Eastern Wind Power.
Linda Haar, who owns the company with her husband, Jonathan, says her company’s business model is two-pronged: Eastern Wind would either sell rooftop turbines to building owners or work out a power-purchase agreement with owners that would allow for the turbine to be installed and owned by Eastern Wind Power, but the company would sell the energy generated from the turbines to the building owner at reduced rates. Tax credits are also available.
Haar is confident the two-year-old company, which has yet to make money, can make it work.
“This is such a huge market out there that anyone producing efficient turbines will do well,” she said.
Computer models indicate that one of Eastern Wind Power’s turbines could produce as many as 55,000 kilowatt hours a year, enough to power four houses.
If a building owner installs eight to 10 units on a rooftop – which Haar says the turbines are designed to do, hence the brand name “Sky Farm” – the energy produced would cover about 10 percent of the needs of a 500,000-square-foot office building.
The three blades of the turbine and the six dihedral struts that connect the blades at a center spindle were constructed of a carbon fiber epoxy composite that is very strong, but also lightweight.
In early tests, the turbine has turned in winds as light as 3 mph, although the minimum wind speed will likely climb to 6 mph when the generator is connected.
The tests have exceeded expectations, Haar said.
“You’re always nervous when you go from computer design to reality,” she said recently. “But it has worked like a charm.”
The apparent success of the prototype adds to Clear Carbon’s already lengthy list of capabilities.
The company already has a strong business producing cello, viola, violin and bass shells out of carbon fibers in a partnership with Luis Leguia, a longtime cellist with the Boston Symphony Orchestra.
Clear Carbon also is busy with work for defense contractors, making things such as experimental ballistic panels designed to repel bullets and explosives.
Dunham has shown he’s not afraid to experiment. The company has developed technology that enables hollow tubes of carbon fibers to be bent into shapes cost-effectively.
Haar said she and her husband – both former urban planners – have working on the turbine design with a team of designers and engineers for more than two years.
The Haars said they were given Dunham’s name by a designer with whom they were working who had also collaborated with Dunham in the boat-building industry in the 1980s.
Dunham jumped aboard immediately, drawn by the environmentally friendly possibilities, and because of the size of the proposed Sky Farm turbine. It wasn’t one of those mammoth 3-plus megawatt turbines planned to be erected off the Rhode Island coast. Instead, Eastern Power Wind’s contraption is a 50-kilowatt unit.
While not an engineer, Dunham and his team suggested tweaks to the design to make production easier. Clear Carbon had made airfoils for other clients, but not like this.
After extensive 3-D modeling, the company shaped special molds for each of the three-piece blades with a CNC (computer numerically controlled) machine that allowed for extreme accuracy quickly. Dunham said he drew upon his previous experience to complete the project, including his time in the boat-building industry.
Still “every day was a learning process,” he said.
The turbine now sits off a taxiway at the Martha’s Vineyard airport, where it has undergone testing since it was shipped there in early August.
Haar said the turbine is intended to spin in winds up to 60 mph. Any higher, an internal brake kicks in.
To test how the blades would hold up in hurricane-force winds, Eastern Wind Power recently persuaded a local airline to back up a turboprop plane to the turbine and open the throttle.
The brake held and the machine withstood the 80 mph winds.
Next step: Eastern Wind Power will assemble the turbine on a roof in downtown Boston after getting permits and Federal Aviation Administration approval.
If the tests continue to prove successful, Haar is confident the company will be producing many more vertical-axis turbines because of the design’s advantages over conventional turbines.
They are quieter, and they catch the wind no matter the direction. And, Haar said, they can be placed as little as 15 feet apart because they don’t disturb wind flow of nearby turbines.
Dunham hopes her predictions are correct. He has the room at his shop to create a production line for more blades if a market develops. •
