Documentary from Germany on wind turbines and infrasound: what you can’t hear can harm you
November 18, 2018
A documentary aired on ZDF, the national public television broadcaster in Germany, featuring multiple interviews with scientists on the topic of wind turbine noise emissions, specifically infrasound.
See the transcript here–open in Google for a translation.)
Here are some excerpts from the report.
Interviews (in German) include conversations with a geoscientist, cardiovascular surgeon, and an expert in noise measurement.
The natural sources of infrasound include, for example, earthquakes and sea surf. Technical sources are – to name just a few – combined heat and power plants, airplanes and also wind turbines. In recent years, doctors and scientists have increasingly dealt with infrasound from wind turbines. Because with the energy turnaround and the expansion of wind power, the load from these sources increases.
People who live near wind turbines often complain of sleep disorders, dizziness, headaches, and difficulty concentrating. Not infrequently dismissed as crazy, they usually have nothing left but to leave the area. Because in the common opinion frequencies below 20 Hertz are not audible and therefore can not cause any health damage.
Perception below the hearing threshold
But is it really like that? Professor Christian-Friedrich Vahl, Director of the Clinic for Cardiac, Thoracic and Vascular Surgery of the Johannes Gutenberg University Mainz feels reminded in such an argument to the early radiologists who experimented with X-rays, but “because they did not see that, only much later realized that they cause cancer. ”
Medical and scientific evidence is increasing that not only some animals, but also humans are able to perceive infrasound below the hearing threshold. No wonder actually, because “infrasound is an energy,” explains Prof. Vahl, “And every energy has physical effects, whether you hear it or not.”. For two years, he and his team have been addressing the question of how infrasound affects the power of the heart muscle. They have already completed two series of experiments investigating the acute effects of infrasound on human cardiac muscle, and the results are available: “In both series of tests, a clear reduction in cardiac muscle strength has been observed with infrasound signals,” says the cardiac surgeon , Something that you do not consciously perceive, So you can still get sick. Or at least have an effect.
Effects on the brain
Investigations by scientists of the University Hospital Hamburg-Eppendorf (UKE)also show effects of infrasound on the brain. They found that infrasound presented below the individual threshold of hearing activates certain regions of the brain. Interestingly, regions that are involved in the processing of stress and conflict. Why this is so is still unclear, but Professor Simone Kühn of the UKE has a hypothesis: “We have speculated that if you hear something consciously and know there is something, you can perhaps better hide it. […] But with things that are so semi-perceptible, you may not have the directive to say, that’s what I’m ignoring now. “Unconsciously perceived things may put you in stress, at least when it’s not. A follow-up study by the UKE is now looking into the question
Worldwide attempts by the military to use infrasound as a non-lethal weapon are another indication that this low-frequency noise can have a negative effect on humans.
Experts estimate that between ten and thirty percent of the population can feel the symptoms of infrasound.
Different measuring methods
Nevertheless, to this day there is no standard for the frequency range below 20 hertz, which would represent the noise level of wind turbines unadorned. On the contrary, on the part of the authorities, a measurement standard is used that partially filters out the infrasound emissions of wind turbines. Frequencies below 8 hertz are completely ignored. By averaging (third-octave analysis) so-called “tonal peaks” are largely smoothed out, which means that certain high rashes are not visible in the result.
The German Federal Institute for Geosciences and Natural Resources (BGR) already showed in 2004 how the emissions from wind turbines in the infrasound sector really look like and how far they reach them. The BGR is responsible for ensuring compliance with the Comprehensive Nuclear Test Ban Treaty ( CTBT). Comprehensive Nuclear Test Ban Treaty) to control. For this purpose, the Federal Institute operates several measuring stations, of which two stations register infrasound. To avoid disturbing the measurement, the BGR determined the distance the wind turbine measuring instruments must have and concluded: ”
As a rule, a distance of about 20 kilometers between the station and the wind farm should be maintained to ensure an undisturbed registration and detection of transients acoustic signals. ”
A distance from which the neighbors of wind farms can only dream.