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Minimization of Motion Smear: Reducing Avian Collision with Wind Turbines; Period of Performance: July 12, 1999 -- August 31, 2002

Technical Report ·
DOI:https://doi.org/10.2172/15004460· OSTI ID:15004460

Collisions with wind turbines can be a problem for many species of birds. Of particular concern are collisions by eagles and other protected species. This research study used the laboratory methods of physiological optics, animal psychophysics, and retinal electrophysiology to analyze the causes of collisions and to evaluate visual deterrents based on the results of this analysis. Bird collisions with the seemingly slow-moving turbines seem paradoxical given the superb vision that most birds, especially raptors, possess. However, our optical analysis indicated that as the eye approaches the rotating blades, the retinal image of the blade (which is the information that is transmitted to the animal's brain) increases in velocity until it is moving so fast that the retina cannot keep up with it. At this point, the retinal image becomes a transparent blur that the bird probably interprets as a safe area to fly through, with disastrous consequences. This phenomenon is called"motion smear" or"motion blur."

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO.
Sponsoring Organization:
USDOE
DOE Contract Number:
AC36-99GO10337
OSTI ID:
15004460
Report Number(s):
NREL/SR-500-33249; XAM 9-29211-01
Country of Publication:
United States
Language:
English