Using Radar to Protect Bats from Wind Turbines
Jul 24th, 2009 Originally Posted by Philip Proefrock
Your first thought at seeing a headline like that would be to assume that there would be some kind of special brake that was being used to slow or stop the blades of the turbine when it sensed a bat getting too close. But that isn’t the case. Wind turbine blades have a tremendous amount of momentum, and can’t effectively be stopped quickly. But radar nevertheless has the potential to significantly reduce the number bats killed by wind turbines.
Researchers at the University of Aberdeen, Scotland discovered that bats tend to avoid radar installations. Although the exact method is not clear, it is possible that the radar somehow stimulates the bats’ ears and creates a perception of unwanted noise.
“This was noticed when radar arrays first started up during World War II,” Racey said. “A portion of radar operators said they heard clicks in their ears when they were switched on.” Radar signals can lead to small but rapid spikes of heat in the head that generate sound waves, which in turn stimulate the ear. “A bat’s hearing is much more sensitive than ours,” Racey noted. “It may be so sensitive that even a tiny amount of sound caused by electromagnetic radiation is enough to drive them out of there.”
In tests, deploying a small radar unit in an area full of insects (tasty feeding ground for bats) showed a 30-40% decrease in bats in the area, although the insects were still there. The radar did not make the insects leave, but the bats stayed away. This could turn out to be a good deterrent to keep bats safely away from wind turbines, and help make wind power that much better.
via: Slashdot