Thomas Priestley, NEWEEP, 10 February 2011
The alternating changes in light intensity that can occur at times when the rotating blades of wind turbines cast moving shadows on the ground or on structures.
Giuseppe Erba, Epilepsy Foundation, 2006T
Certain individuals are born with special sensitivity to flashing lights or contrasting visual patterns, such as stripes, grids and checkerboards. Because of this condition, their brain will produce seizure-like discharges when exposed to this type of visual stimulation.
Erik Nordman, Assistant Professor of Natural Resources Management, Grand Valley State University
Shadow flicker occurs when the sun is low in the sky and a wind turbine creates a shadow on a building. As the turbine blades pass in front of the sun, a shadow moves across the landscape, appearing to flick on and off as the turbine rotates. The location of the turbine shadow varies by time of day and season and usually only falls on a single building for a few minutes a day. Shadows that fall on a home may be disruptive. Shadow flicker has been a concern in Northern Europe where the high latitude and low sun angle exacerbate the effect.