Meeting Abstract
P3.35 Thursday, Jan. 6 What is the cost of going green? HALE, A.M.; KARSTEN, K.B.*; Texas Christian Univ.; Texas Christian Univ. k.karsten@tcu.edu
Wind energy is expanding at an incredible pace nationally and internationally. The benefits are intuitive and obvious: a renewable source of energy, low carbon emissions, and in arid environments, the lack of water required for energy conversion is an important aspect. While these benefits have spurred a movement for the U.S. to convert to 20% wind energy by the year 2030, this industry is not without costs and in fact, wind energy may negatively impact bird and bat populations. In Texas, the wind industry has expanded exponentially compared to other states. We conducted a study at a wind energy facility in the cross timbers ecoregion of north-central Texas consisting of 75 1.5-MW GE turbines extended over 48 km2. Here, we present data on bat mortality from our first study year. From 26 Mar-30 Oct 2009, we conducted systematic mortality searches at a subset of the wind facility’s 75 turbines. During this time period we found 458 bat carcasses representing 5 species, the majority of which were Eastern Red Bats (Lasiurus borealis) and Hoary Bats (L. cinereus). The majority of bat fatalities occurred between mid-July and mid-September, which coincides with the fall migration season for North American tree bats. After accounting for searcher efficiency and scavenger removal rates, we estimated that 3,388 to 6,619 bats (95% CI) were killed at this wind site in 2009. These staggering numbers present a conservation challenge: what is the cost of going green? One proposed solution is to curtail turbine activity during times of high bat activity, usually during periods when wind speeds are low but still high enough to generate electricity. While this mitigation strategy shows promise—in both financial and conservation terms—we propose an experimental study using statistical modeling to optimize curtailment parameters that we hope will significantly reduce mortality, but at a lower cost to wind energy companies.
