At a time of growing concern over the rising costs and long-term environmental impacts from the use of fossil fuels and nuclear energy, wind energy has become an increasingly important sector of the electrical power industry, largely because it has been promoted as being emission free and is supported by government subsidies and tax credits. However, large numbers of bats are being killed at utility-scale wind energy facilities, especially along forested ridge tops in the eastern United States. These fatalities raise important concerns about cumulative impacts of proposed wind energy development on bat populations.
I will discuss our current state of knowledge on patterns of bat fatalities at wind facilities and present findings from ongoing studies on the effectiveness of operational curtailment and acoustic deterrents to reduce bat fatalities. Operational curtailment studies indicate that bat fatalities can be reduced from 44 to 93% during selected high risk periods of the year and with marginal power losses. Research and development of acoustic deterrent devices is continuing and I will present results from an ongoing field test comparing fatalities at turbines with and without deterrents and discuss future research needs and efforts. I also will discuss challenges and opportunities for developing solutions to reduce or eliminate bat fatality at wind facilities.