Windswept_ The Story of Wind and Weather - Marq de Villiers [123]
I had seen earlier versions of wind turbines, in California and Maine and other places; the wind farm in the Altamont Pass east of San Francisco consists of more than six thousand of the things, of assorted vintages and designs, and I remember that many of them made a variety of more or less unpleasant noises—clanking and creaking, sometimes whining, occasionally as loud as an unmuf-flered lawnmower. The blades at Pubnico made hardly any sound at all. In a light wind you could hear a faint swishing if you stood directly underneath, but if the wind picked up, the sound of the breeze actually drowned the sound of the blades moving, and they appeared completely silent.
As of spring 2005, fifteen 1.8-megawatt Vestas turbines from Denmark had been installed. The project's financing was an example of what was becoming a familiar pattern in such green projects. Part of the ownership is local—sensible developers always try to head off on-the-ground opposition by getting the locals involved, and one of the d'Entremonts, Brad, is part owner. The rest is venture capital, money that flows in partly because of an assured customer base; Nova Scotia Power, the provincial generating company, has guaranteed a certain price for a kilowatt hour—a price made possible by a complicated series of incentives and tax breaks, part of the Canadian drive to meet its Kyoto commitments. By 2004 NSP, a notorious coal burner, was getting about 10 percent of its energy from renewables, mostly hydropower, and was looking to increase that to about 25 percent by 2006. About 100 gigawatt hours will come from Pubnico once the wind farm is complete. It would be the largest wind farm in the Canadian Maritime Provinces, with a nominal output of some 30.6 megawatts and an annual production of 100 million kilowatt hours of energy. According to the promotional material cheerfully handed to all and sundry by the builders, this would be "enough to prevent the production of 90,000 tons of CO and 50 tons of NO annually, roughly the equivalent of not driving 16,000 cars or planting 750,000 trees for 60 years. It would be enough energy to supply some 13,000 homes." Nice round numbers, these, but they should be treated with caution.
I spent an hour or so poking about the turbines, being regaled with statistics by an eager maintenance engineer, a local lad who had been taken off to Vestas headquarters in Denmark for training. He reeled off the numbers: the foundation of each tower is 15 feet in diameter and 30 feet deep, the bottom section anchored by 30-foot, two-inch-thick steel bolts spaced every foot around the tower, inside and out. The bottom section of the tower is 37 feet long, with a diameter of 13.2 feet tapering to 12, and weighs 48 tons. The uppermost of four sections that are bolted together is itself 80 feet long and weighs 43 tons. The nacelle where the rotor is housed weighs 68 tons, the rotor another 39 tons. The nacelle is the size of a school bus, and is large enough inside to jump up and down on its floor without hitting the roof. For the brave or exceptionally foolhardy, at the very top is a sunroof, with an apparently magnificent view—I took his word for it. You get to the top by ladder, 270 feet straight up. And yet so finely balanced is the whole structure that a single technician can haul on a cable and turn the whole massive thing by hand.
I'm dwelling rather longer on Lower West Pubnico and its generating capacity than might seem justified, partly because the mere fact that such a facility, with its sophisticated engineering and complex but by-now-familiar financing pattern, has made it to a part of the world that is hardly an industrial powerhouse is a good indication of the wind rush that is consuming the energy industry. Wind farms are being built everywhere from Point Reyes to Nantucket, from the Gulf of Mexico to Wisconsin, from the interior of British Columbia