According to the FAA, wind farms with more than three turbines of heights over 200 feet above ground level should be lighted conspicuously to aid in pilot navigation. Flashing red or white lights are preferred, with red being most effective. Therein lies the problem.
As early as 1979, the U.S. Environmental Protection Agency (EPA) identified night sky brightness as a potential environmental stressor. This occurs because lighting alters the natural periods of light and darkness in nature.
Part of the problem is inefficient or unnecessary lighting. According to the National Optical Astronomy Observatory, Americans waste more than $2 billion each year on wasted light. That amounts to about 17 billion kilowatt-hours of energy, with the added threat of increased greenhouse gas emissions.
Effects on Human Health
Putting aside the energy costs, light pollution carries other risks. The American Medical Association (AMA) warns that artificial light exposure can pose health hazards. A study by University of Haifa’s Israeli Center for Interdisciplinary Research on Chronobiology showed an increased risk of developing prostate cancer. The AMA’s official stance is that more research is needed to document the adverse effects.
Wind Turbines and Artificial Light
Lighting of wind turbines is a necessary safety precaution. However, the fact that it is done for this reason does not negate the potential health hazards it poses. In addition, flickering lights is a documented migraine trigger in some individuals.
Another concern lies with the impacts on ecosystems. Artificial lighting can disrupt navigation in wildlife. For nocturnal animals, it can be especially disturbing. It can also affect pollination of night-blooming plants because of the change in the photoperiod and effects on moth navigation.
Light pollution may be a common occurrence in urban areas. However, wind power heightens the risk for human health and environmental impacts in rural areas where wind farms are often located. Lighted wind turbines can attract night-flying birds and bats.
According to the American Bird Conservancy, nighttime lighting is increasing at a rate of 5 to 10 percent each year. The ill effects of light pollution will increase, putting wildlife and humans at risk. The fact that the AMA has addressed this problem provides a compelling reason for the industry to re-assess its impacts on society and the environment.