Fixit: Wind turbines not ready for home use

Q Does it make sense to add a wind turbine to my home?

By Karen Youso, Star Tribune

Last update: October 22, 2007 - 5:40 PM

Q Does it make sense to add a wind turbine to my home?

A Probably no, at least not yet.

"Small wind technology is immature in the United States," said state energy specialist Phil Smith. Only recently has the industry agreed on common standards, he added. However, you can buy home turbines via the Internet.

If you do decide to put one in, be sure it meets electrical codes, is tested to UL standards, and realize that there will be special considerations. It can be difficult, for example, to add a turbine to the average Minneapolis home. City ordinance won't allow them on buildings less than four stories high, and then not more than 15 feet above the building. It may take more height than that to catch reliable breezes.

Other considerations are:

• Movement and vibration. Most wind turbines deliver tremendous amounts of physical energy to the building, said Smith. In many cases, that can cause structural damage to the house. That can be solved by mounting it on a pole next to house, however.

• Noise and hazard. Current technology is fairly noisy, potentially creating a nuisance for neighbors. And there's the danger of a blade or ice coming off from horizontal-axis turbine designs.

• Turbulence. Air moving around the contours of urban landscapes -- buildings, trees and vegetation -- creates rough spots and uneven airflow or turbulence. Current wind turbines are affected by turbulence, a stress that can shorten turbine life, Smith said. To avoid turbulence, turbines need be to high. The state of Minnesota recommends a minimum height of 100 feet combined with an additional 30 feet above the nearest object within 300 feet of the turbine.

But stay tuned. Change is in the air.

Already you can see small wind turbines attached to sailboats, Smith said. And in Europe, where the cost of energy is much higher, small turbines are sometimes attached to buildings.

In addition, a number of people are trying to build systems that include a small tower and its own inverter. But, according to Smith, the trouble and expense of adding a wind turbine to your home should not be considered until after you've made every energy-efficient change possible to reduce your electrical needs.

"It is always much cheaper to be energy-efficient than to generate power," he said.

For more information on wind energy, contact the American Wind Energy Association at www.awea.org/smallwind.

Send your questions to Fixit in care of the Star Tribune, 425 Portland Av. S., Minneapolis, MN 55488, or call 612-673-9033, or e-mail fixit@startribune.com.

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