A Rooftop Windmill Of Your Very Own

As projects to build "wind farms" of massive, electricity-generating wind turbines continue to multiply, so do the ranks of "not in my backyard" protesters. The turbines, some with blades that sweep as high as a 20-story building, are increasingly seen as unsightly and dangerous manifestations of the industrialization of the countryside. "The volume is going up higher on opposition to wind farms," says Kathy Belyeu, spokeswoman for the Washington, D.C.-based American Wind Energy Association. Although protests have generally failed to nix many farms, they frequently translate into costly delays or relocation to sites with less favorable winds.

Wind advocates thus have high hopes for less obtrusive wind technology: specifically, high-performance, nonpolluting rooftop microturbines. Generally not much bigger than a dish antenna, they hardly mar the skyline. And if wind conditions are optimal, they can satisfy a typical household's appetite for electricity. Although a microturbine produces less than one thousandth the power of a 20-story turbine, the electricity need only be piped a short distance into the house rather than sent over long distances. The microturbine can also contribute to the energy grid via a short power line that connects to utility lines running along the street. Various models of the turbines, which generally range in price from $1,000 to $8,000, have started springing up on top of houses and buildings in Europe and North America.

Demand has risen so quickly--roughly doubling in the past 12 months--that companies are having trouble making the minimills fast enough. Renewable Devices, an Edinburgh-based manufacturer, which is growing at 300 percent a year, priced a popular turbine at £5,000 while it ramps up production (it plans to drop the price by two thirds by December). Many other manufacturers are lowering prices as the growing market provides economies of scale and local authorities expedite use permits. (The turbines aren't much louder than the wind, and birds are no more likely to fly into them than into windows.)

Earlier this year, the Dutch city of Hoofddorp erected a turbine on its town hall "to set an example," says Environment Policymaker Ruud Mesman. The move kicked off a campaign to install enough turbines to cover 10 percent of the city's electricity needs within 20 years (the city now advises builders on the benefits of "small wind" before issuing construction permits). In May, Chicago will begin a turbine test on the Daley Center skyscraper to figure out how to issue permits and whether to promote the technology with tax incentives.

Most rooftop turbines are designed to pay for themselves after about five years of moderately favorable winds--conditions common in temperate climates like those of Europe, the United States and Japan. After that, the juice is free, save maintenance costs, until the motors burn out after an additional 15 or so years. Rising electricity costs are sweetening the deal, as is the proliferation of "net metering" laws that require utility companies to purchase the unused small-wind electricity fed onto the grid. Five years ago half a dozen EU countries obliged energy companies to buy this so-called spill; now 24 countries do. Thirty-nine U.S. states have passed net-metering legislation. Of course, microturbines also make a satisfying display of one's green credentials and self-reliance. In a world of energy turmoil and global warming, personal windmills are becoming fashionable.

A Rooftop Windmill Of Your Very Own | News