Onecomplaint
voiced by wind turbine opponents is that the turbines create too much
noise — even noise below the range of human hearing, known as
infrasound. These concerns fuelclaims about
“Wind
Turbine Syndrome,”
which advocates say is a medical condition that involves mental
health problems, heart disease, and vertigo.
A
study by an acoustic
engineering group in
Australia found that that infrasound generated by wind turbines is
less loud than the infrasound created by a listener’s own
heartbeat. It found that wind turbine infrasound does increase as
wind speed increases, but this is often masked by the natural noise
of wind moving through the area.
The
Association of Australian Acoustical Consultants said that
“those investigations conclude that infrasound levels adjacent to
wind farms are below the threshold of perception and below currently
accepted limits set for infrasound.”
Those
limits are levels of infrasound that people encounter already,
created by natural sources like breathing, wind, and waves, as well
as mechanical sources like aircraft, traffic, and fossil fuel
industry. The study noted that wind turbine noise is all relative:
Our environment has lots of infrasound already in it, the levels generated by wind farms from our point of view are quite low in comparison and they’re no higher than what is already out there in the natural environment. … People themselves generate infrasound through things like their own heartbeat, through breathing and these levels of infrasound can be substantially higher than an external noise source.
Wind turbines outside of
Atlantic City, NJ. (Photo: Donna Connor/AP)
It’s
one thing to have conflicts about the placement of new infrastructure
near homes, which can be mitigated by proper communication between
residents and developers. But that is different than faux
medical ailments involving
infrasound.
A study by
the Massachusetts Department of Environmental Protection found that
there was no evidence for “Wind Turbine Syndrome.” It also found
no concrete evidence for the “flicker” of the shadows of rotating
wind blades causing seizures or other symptoms.
An
experimental study in
the journal Health Psychology found that people would report the
experience of wind turbine syndrome caused by infrasound if they
merely had the suggestion. Participants either experienced real
infrasound or a fake alternative, and what determined if they
experienced symptoms wasn’t the type of sound — it was
whether they were told beforehand about the supposed dangers of
infrasound.
The
well-known placebo has a lesser-known opposite called a “nocebo.”
This is the expectancy of the harm of something that most people have
likely never heard of before experiencing it. The study by the
acoustical experts removed another plank from “communicated
disease.”
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