Annual energy production (AEP) from wind farms in bat-infested regions could see a significant boost while greatly reducing the number of creatures killed in turbine-rotor collisions, to judge by tests of an innovative deterrent technology being pioneered by US outfit NRG Systems.

Results from trials at EDF Renewables’ 175MW Pilot Hill development in Illinois, where a spread of 15 ultrasonic acoustic systems were installed on turbines last year, showed an overall improvement in AEP of almost 2% and a reduction in bat fatalities of an average of 67%.