Scientists develop silencer for wind turbines

"Voom! Voom! Voom!" For those living very close to wind farms, it's a familiar sound, a low-frequency whine emanating from the turbines.

For some, the sound is an annoyance. For others, such as Dr. Nina Pierpont, author of "Wind Turbine Syndrome: A Natural Experiment," it's responsible for a host of debilitating medical problems ranging from headaches to night terrors to childhood behavioral problems.

Whatever the effects are, German engineers have developed a way to dampen the noise.

Current wind turbines do have sound-dampening systems, but as the science news site Physorg explains, they work properly only at certain frequencies, whereas the wind velocity varies. This means that some turbines that are close to residences are not permitted to spin at their top speed, wasting potential electricity.

Researchers at the Fraunhofer Institute for Machine Tools and Forming Technology IWU in Dresden have developed a damper that changes with the wind. Using vibration sensors, this system generates "negative vibrations" that cancel out those of the wind turbine.

The researchers next step will be to perform field tests on their active vibration dampers to see if they work in high-velocity winds. If they do, then this system could bring wind turbines into more neighborhoods.