WIND MOVES FAST TO PROTECT BATS

Bat death causes 70MW project shutdown
James Quilter, 19 October 2011 (Windpower Monthly)

"…The [70 megawatt] North Allegheny project [in Pennsylvania]…owned by Duke Energy and [using] Gamesa 2MW turbines…was closed [at night] by the US Fish and Wildlife Service after [a] dead bat was discovered under a turbine…

"The bat was an Indiana Bat and is protected by the federal endangered species act. It was discovered during routine monitoring of the wind farm."

Indiana bat (from Windpower Monthly -- click to enlarge)

"Many bat deaths are caused by a phenomenon known as barotrauma, whereby a change in pressure between turbines causes the creatures’ lungs to explode.

"It is believed operational changes such as increasing the speed at which a wind turbine starts generating energy from 3.5-5.5m/s can reduce bat fatalities by 50-80%...[and] preliminary results from studies on acoustic devices, which generate ultra-high-frequency sounds to deter bats from turbines, show a reduction in mortality by up to 70%."