27 Jan 2003, Posted by heingart in Tech, The Associated Press, 0 Comments
Dutch move the modernized windmill into town
In the small town of Ede, whose old wooden mill generates more tourism than energy, a shiny new stainless steel windmill on the roof of a technical school barely whispers as its blades spin in a brisk winter breeze.
Such high-tech turbines, which feed kilowatts to local power grids, are now poised to conquer a new frontier – the modern city center, often fused into building designs and barely noticeable from a distance.
They are lighter, quieter, and often more efficient than their lumbering rural counterparts, and built to take advantage of the extreme turbulence and rapid shifts in direction that characterize urban wind patterns.
Germany, Finland and Denmark have also been experimenting with the technology, but the ever-practical Dutch are natural pioneers in urban wind power, “mainly because of the lack of space here,” said Sander Mertens, a wind energy researcher at the Delft University of Technology.
Dutch cities including Amsterdam, the Hague, Tilburg and Twente plan to install urban windmills in 2003, mostly small-scale projects with fewer than a dozen turbines each.
“First we want to see how it works out,” said Andre Struker of Amsterdam’s environmental department. “It’s still a bit symbolic, a way of bringing wind energy closer to the people.”
The prospect of a new, environmentally correct energy source has attracted Dutch energy companies. Cor De Ruiter, a spokesman for one company, Eneco, said research has indicated there are 50,000 locations in the Netherlands where small urban turbines could be installed.
The new windmills pay for themselves in about five years, according to the Dutch manufacturer Prowin. And as the technology improves, prices will drop further. The smallest models weigh roughly 440 pounds and can be installed on a roof in a few hours.
“All the technical problems are behind us now,” says Dick Sidler, an engineer at Core International, another company that builds the latest-generation turbines.
Current models cost $5,000 to $12,000. The windmill on the roof of the technical school in Ede can generate about 5,000 kilowattt hours of energy per year, which would cost $900 if taken from the fossil-fuel-powered grid.
That’s more than enough for the average Dutch household, which consumes roughly 3,500 kilowatt hours per year – the average American family uses 10,000 – although most new windmills are designed more for public or commercial buildings than for private homes.
The Netherlands, with 16 million people crowded into a country twice the size of New Jersey, is the most densely populated in Europe. It generates less than 1 percent of its electricity from wind. In Denmark that figure is 18 percent; Germany 4 percent; in the United States a fraction of 1 percent.
But Holland has on average 245 days per year with wind speeds of 13 to 19 mph, which can power even the biggest turbines. Many of the new urban turbines can begin spinning with wind speeds as low as 5 mph.
With fewer moving parts than their rural kin, urban turbines generally require less maintenance. And because the energy they generate is close to where it is consumed, less electricity dissipates while crossing transmission lines.
The urban turbine could also get a boost from European initiatives to increase the viability of sustainable energy, leading to heightened interest in “zero-energy” buildings that generate their own power. A prototype building that accelerates the wind through an integrated turbine was recently constructed in Oxfordshire, England.
The recent liberalization of European energy markets now allows customers to choose what kind of sustainable energy they buy, with wind energy among the most popular.
Problems remain, however: notably public safety concerns.
“Just one accident would be enough” to quash enthusiasm for the idea, said Mertens, the researcher. One theoretical danger, runaway windmill blades, could be averted by covering the turbines with gratings, he said, but the effect of vibrations on local buildings and inhabitants is still unknown.
So, might Manhattan or Chicago soon be dotted with spinning daisywheels?
“I don’t think it’s reasonable to begin with the giant skyscrapers yet. It would first have to be tested for safety and efficiency,” said Paul Schraven, a spokesman for Lagerwey, another manufacturer. “We don’t know what it would be like to work there, in an office next to one of the big turbines. It might be too hectic.”
(Originally published by the Associated Press in January 2003)
(Original photo caption: An urban turbine spins on the rooftop of the ROVC (Dutch acronym for Regional Training Center) school in Ede, Netherlands. Holland’s graceful wooden windmills have been losing ground in the Dutch countryside to “wind farms” of stark metal turbines. Now, the environmentally-conscious Dutch are experimenting with urban turbines in city centers. Light, quiet and efficient, they can be placed unobtrusively on rooftops and generate up to 7,000 kilowatt hours of electricity a year, more than enough to power an average Dutch home.)