What's all the noise about wind turbine noise?
By Lynda Barry
"There can be no doubt that groups of industrial wind turbines ("wind farms") generate sufficient noise to disturb the sleep and impair the health of those living nearby," states Dr. Christopher Hanning in a recent report titled "Sleep Disturbance and Wind Turbine Noise." [Click here to download full report]
For those of us who have stood directly beneath an industrial wind turbine on a clear afternoon, this statement will come as a surprise. What noise could Dr. Hanning be referring to? The only noise most of us hear at the base of a turbine is the swooshing of the blades above us.
Life in an industrial wind farm is something very few of us have experienced. Most of us don’t know that the quietest place near a turbine is directly beneath it. It’s a bit like standing beneath a speaker placed 40 stories above you. Step out about 1000 feet downwind from the turbine and you will have a different experience, especially after sundown. Though we may not know the physics behind the phenomenon, most us notice sound carries further at night, especially in open rural areas. This turns out to be especially true for wind turbine noise. The noise Dr. Hanning writes about is nighttime turbine noise.
Interestingly, very few (if any) of those responsible for creating the setback distances and turbine noise limits have spent any nights in homes near wind turbines. Nor have they sat through an hour of severe shadow flicker inside of a home.
Why should they? The modeling software used for siting virtual turbines near virtual homes assures them that they’ve gotten their calculations right. So if real people are having problems with real noise and real flashing shadows they must be making it all up.
But are they?
Daniel Haas, a Wisconsin wind farm resident who has been living with turbine noise for nearly two years put it this way in one of his many letters of complaint to the wind company. The setback from homes in this project is 1000 feet.
“I really do not know much about noise levels but what is the noise level of a commercial jet coming through the middle of your house at 2:00 in the morning?
I really am getting tired of the misinformation given to anyone with a complaint. There are different noise levels and you only talk about one.
The low level noise that I am concerned about is extremely loud and actually shakes the whole house. It wakes the whole family up at night. It also spooks our horses so bad that we can't even ride them on our trails anymore. Our dogs won't even come out of their kennel because they’re afraid of the noise.
As for the shadow flicker it is terrible. It affects all of my 100 acres. Yes all 100 acres. That is my home.”
In May of 2009, the Minnesota Department of Health issued a white paper that identified half a mile as the setback beyond which turbine noise and shadow flicker were not a major concern.
This setback is unacceptable to wind developers because it restricts the number of turbines they can profitably site in more populated rural areas which are also more likely to have the transmission lines they need nearby. Profits (and government subsidies) rely on being able to site the greatest number of turbines in the smallest amount of space. Their eyes are on a prize other than protecting the environment or protecting the health of those who will live inside of their wind farms. From a business standpoint this may make sense, but from a human standpoint it’s a formula for trouble.
Our legislature may also find safer setbacks unacceptable because our renewable energy mandates. Setbacks that are better for families mean fewer turbines for the state to make that goal. And though wind energy isn’t the only renewable energy choice, most consider wind to be the cheapest way of getting there, even if it means harming people in the process.
This is made much easier by a general misunderstanding about what the real problems are when wind turbines are sited too close to homes. How close is too close? If you go with a wind developers recommendations, 500 feet from your home is not considered too close. If you go with the National Academy of Sciences, the Congressional Research Service, The World Health Organization, the peer-reviewed study of wind farm residents by Dr. Nina Pierpoint, and Minnesota Department of Health, you’ll get a minimum setback of 2640 feet out to 1.5 miles.
The wind industry has not been able to provide any scientific or medical data which supports setbacks any closer than this, but they have been very good at dismissing and ridiculing those with complaints. For those of us who have witnessed well known instances of organized corporate denial of negative health effects caused by their product, this marginalization of wind farm residents who tell us their families are suffering raises red flags.
The general public knows very little about life in a wind farm. Most don’t know about the serious problems wind turbines cause when placed too close to our homes, or within ecologically sensitive areas such as migration corridors. For now, wind industry is enjoying its image of being a benign industrial-scale source of clean energy. Anyone who dares to challenge this Green Goliath should beware. The David who asks the hard questions about proper setbacks will be shouted down as an anti-wind, anti-environment, anti-green, NIMBY.
But the problem is not going away. As more families are forced to suffer because unsafe setbacks for the sake of wind industry profits and renewable energy deadlines, more Davids will appear. In the meantime, how many lives will be made miserable before we get this right?
In his report on turbine noise and sleep disturbance, Dr. Hanning finds current calculated measures of wind turbine noise “woefully inadequate” and says he is unconvinced by what he terms, "badly designed industry and government reports which seek to show there is no problem.
"Calculations cannot measure annoyance and sleep disturbance,” he writes, “Only humans can do so."
How close is too close? Wind farm residents now living in the wind farms in our state are trying to tell us,-- but right now, who’s listening?