Huge windmills will spin 'juice' into 1,500 homes
East Granby, Conn.
Slicing through the middle of the long, steel building, an almost equally long, tapered blade, looking like half of a giant propeller, appears to hang suspended, waiting to be sent flying through the cold December air blowing outside.Skip to next paragraph
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This, however, is not a blade for flying. It is part of a pair of fiber-glass blades that, mounted to a steel housing bigger than a railroad boxcar, will face up to powerful winds and generate enough power to light lamps and electrify TV sets in up to 1,500 homes.
The 125-foot-long blade is resting in the Hamilton Standard company's "wind turbine facility," about halfway between Springfield, Mass., and Hartford, Conn. The facility, dedicated by the United Technologies Corporation division in October, is putting together the first pieces of what is to become a production line of wind turbines.
These tall, graceful structures need to be called "wind turbines." "Windmill" simply wouldn't do them justice. Standing on a 260-foot steel pole, the narrow, fiber-glass blades will stretch 260 feet from tip to tip. Even Don Quixote, in his wildest fantasies, would never consider tilting with these things.
And while ancient windmills served just one farm, and much of the attention today still centers on windmills that can generate electricity for a few homes or offices, these contraptions are being designed and built to feed electricity to the hungry maw of the utility market, each one supplying up to four megawatts of power, enough to save 20,000 barrels of oil a year.
Wind machines like this, says Ben Wolff, executive director of the American Wind Energy Association, will number between 30,000 and 50,000 by the end of this century, compared with 1.3 million of the smaller windmills. But sleek behemoths like those being built at Hamilton Standard will generate twice as much electricity, enough to replace nearly 1 million barrels of oil a day, compared with about 490,000 for the smaller versions.
"The scale is staggering," Mr. Wolff said. "There is no question that over the long haul, large wind machines will produce much of the energy the country will need." One Department of Energy (DOE) study projected the United States would get 20 to 25 percent of its electricty from wind by the year 2000.
It will take more than one manufacturer to produce 50,000 wind turbines, but so far, Mr. Wolff notes, Hamilton Standard is in a unique position: It is the only company to be making large-scale wind turbines without any government assistance. The only wind turbine larger than Hamilton Standard's, with a 300 -foot blade span, is a Boeing product -- built with the aid of a grant from DOE. Several other companies, he said, are developing wind turbine systems, but also with government backing.
"Hamilton Standard is in kind of a high-risk position with this," Mr. Wolff added. There are a number of firms building smaller windmills on their own, but "this is certainly the most substantial private investment in large wind turbines."
The company has invested some $15 million in this project, said Arthur H. Jackson, director of its wind turbine program. It is not totally alone in the effort, however. A Swedish company is building the boxcar-size housing that connects the blades to the gearbox and controls. The 150-ton box, called a nacelle, also contains the generator that converts the motion of the blades into electricity, which is transmitted to power stations.
One of the first two wind turbines produced by these companies will be set up in Sweden. The other will stand near Medicine Bow, Wyo., which will eventually be the location of a wind turbine "farm" with dozens of wind machines producing, company officials claim, about the same amount of electricity as a small nuclear power plant.
Inside the Connecticut wind turbine facility, where the blades are being made , a computer-controlled winding machine stands to one side of the suspended blade. Dozens of strands of fiber-glass filament stream out of a sliding boom on the machine, pass through an "eye" that brings the strands together, and are wound onto a mold -- also made primarily of fiber glass -- which is turning slowly, like a shish kebab on an electric outdoor grill.
While the mold is turning, the winding machine moves beside it on a steel track, from one end to the other, back and forth, making hundreds of trips. As it moves, the boom slides in and out from the machine, so the eye is always the same distance from the surface of the curved, tapered blade. When the winding is complete, some 2,000 miles of fiber glass will have been spent on its surface.
When the blade is finished, the whole thing will be put in a 200-degree F. oven and baked until the fiber glass is hard and a wax that was spread on the mold melts. The melted wax permits the mold to be slipped out -- carefully, with jacks and hoists, sales engineer George Walker said -- and the hardened fiber glass shell is now a hollow wind turbine blade.
This type of blade, he explained, is light enough to permit the winds to move it easily and still provide maximum power. At 30,000 pounds per blade, it is also strong enough not to break in high winds, test engineers have told him.
As the wind pushes against the blades, they will turn at a methodical 30 revolutions per minute, no more, no less. If the wind is too slow -- less than 15 miles an hour -- the blades will not move until there is enough breeze to reach 30 r.p.m. And if there is too much wind -- over 60 miles an hour -- the blades will be angled into the wind, locked in a vertical position, and the turbine will be stopped.
"You would have to make everything stronger to work in higher winds," Mr. Walker said. "And it would be more expensive. We had to decide what the optimum speed would be and still keep the costs reasonable."