Wildlife expert Dan Boone presented these slides at the 38th North American Symposium on Bat Research held in Scranton, PA in October 2008. Mr. Boone's presentation focused on the trade-offs of wind energy development in Eastern US balancing the benefits of this energy resource against the environmental risks, particularly to bats. Note that slides # 27, 32 and 33 of the presentation provide graphs which quantitatively estimate the potential impacts on bats and forest habitat resulting from the projected intensity of wind energy development within the eastern US states which comprise the bulk of the Appalachian mountain region. The summary slide from the presentation is listed below. The full presentation can be accessed by clicking on the link at the bottom of this page.

For two decades, the capacity factor of wind power measuring the mean energy delivered by wind turbines has been assumed at 35% of the name plate capacity. Yet, the mean realized value for Europe over the last five years is closer to 21% thus making levelized cost 66% higher than previously thought. We document this discrepancy and offer rationalizations, emphasizing the long term variations of wind speeds. We conclude with the consequences of the capacity factor miscalculation and some policy recommendations. Click on the link below to download the full document.

This paper documents the results of an in-field test at the Maple Ridge wind energy facility in New York to determine the effectiveness of using an experimental acoustic bat deterrent to reduce bat mortality. The executive summary excerpted below suggests the results were inconclusive. Most bat experts remain unconvinced that acoustic deterrence will be a suitable mitigation approach to reduce bat fatalities at existing turbines.

While the public and many decision-makers generally believe that wind energy is environmentally benign, it may entail significant detriments to wildlife and essential habitats, which need to be more clearly understood, and addressed. State fish and wildlife agencies should be at the forefront of cooperative development and implementation of measures to characterize, avoid, minimize and effectively mitigate the impacts of wind energy development on natural resources. Therefore the position of the Association of Fish and Wildlife Agencies, in regard to wind energy development is to: ...

This document authored by Acoustic Ecology Institute provides a comprehensive overview of noise issues pertaining to utility-scale wind energy development. This AEI Special Report will be continually updated, incorporating new research, more recent reports, and suggestions/comments from readers. Planned topics to be added over time include: effects of noise on wildlife and habitat, offshore wind energy, and the health effects of chronic noise exposure.

ABSTRACT: Wind power is one of the fastest growing sectors of the energy industry. Recent studies have reported large numbers of migratory tree-roosting bats being killed at utility-scale wind power facilities, especially in the eastern United States. We used thermal infrared (TIR) cameras to assess the flight behavior of bats at wind turbines because this technology makes it possible to observe the nocturnal behavior of bats and birds independently of supplemental light sources. We conducted this study at the Mountaineer Wind Energy Center in Tucker County, West Virginia, USA, where hundreds of migratory tree bats have been found injured or dead beneath wind turbines. We recorded nightly 9-hour sessions of TIR video of operating turbines from which we assessed altitude, direction, and types of flight maneuvers of bats, birds, and insects. We observed bats actively foraging near operating turbines, rather than simply passing through turbine sites. Our results indicate that bats 1) approached both rotating and nonrotating blades, 2) followed or were trapped in blade-tip vortices, 3) investigated the various parts of the turbine with repeated fly-bys, and 4) were struck directly by rotating blades. Blade rotational speed was a significant negative predictor of collisions with turbine blades, suggesting that bats may be at higher risk of fatality on nights with low wind speeds. (JOURNAL OF WILDLIFE MANAGEMENT 72(1):123-132; 2008)