Wind Energy
Are Wind Turbines Noisy?
A common concern about wind power plants is noise: Don’t those huge turbines make a lot of noise when they’re spinning? While turbines do make noise, it is generally not loud enough to be disruptive to people’s day-to-day activities. Earlier turbine models were much noisier than today’s models, which have been redesigned to be more streamlined and efficient (and considerably quieter!). According to a study by a panel of doctors, audiologists and acoustical professionals from the US, Canada, Denmark and the United Kingdom, the sounds generated by wind turbines are not harmful to human health. The study, commissioned by the American Wind Energy Association and the Canadian Wind Energy Association, found that the noise generated by wind turbines is no worse than the noise generated in average urban environments. The mechanical components of wind turbines do, of course, make some noise. But since the nearest houses are usually at least 300 meters/984 feet away, RenewableUK asserts that the noise that can be heard inside the houses would be comparable to that inside a quiet, air-conditioned office.
People who live near the turbines may argue this point, though. For example, in Minnesota (in northeastern US), where people may live within 152 meters/500 feet of turbines in rural areas, critics say the noise is a constant hum that disrupts their lives. New York doctor Nina Pierpoint, who has studied the effects of turbines on people, developed the term “wind turbine syndrome,” the symptoms of which are ear pressure, sleep disturbance, vertigo, nausea, blurred vision, memory problems and panic attacks. Critics in Minnesota want regulations to mandate greater distances between turbines and homes (from Noise, Shadows From Wind Farms are Creating Uproar in Rural Minnesota, by Tom Meersman, Minneapolis Star Tribune, 17 Jan., 2010).
Shadow Flicker
Wind turbines’ turning blades can cast a moving shadow on nearby buildings. This is called “shadow flicker.” The American Wind Energy Association says wind power plant developers can calculate whether a flickering shadow will fall on a given location near a wind farm and how many hours in the year it will do so. This makes it possible for developers to erect turbines in locations that won’t cast a shadow on houses. People who live near turbines that cast shadows on their homes often say the flickering is irritating—one US farmer whose home is located 900 feet/274 meters from a wind turbine with 122-foot/37-meter blades compared it to a light switch being flipped on and off for hours at a time.
