The negative impact of wind turbines is already known to be considerable and residents around wind turbine parks report more health problems than elsewhere. Now infrasound, low-frequency noise, from wind turbines has proven to be stronger than expected and this has been associated with negative effects on human health and well-being, as well as with an enormeous damage to insect-life and biodiversity, according to studies.
Infrasound refers to sound waves with frequencies below the lower limit of human audibility, below 20 Hz and down to 0.001 Hz. These low sounds can travel vast distances with little dissipation. Often described as inaudible to humans, under normal conditions these sound waves are imperceptible to the human ear, it can be felt as vibrations in various parts of the body if it is in higher intensities and it can actually be heard if the sound pressure is sufficiently high. The hearing threshold for infrasound has been measured down to 1.5 Hz.
Most studies of wind turbine sound effect are limited only to audible sounds. Wind turbines, at least in Sweden, are not allowed to make noises over 40 decibel A (dBA). This measurement, dBA, is solely for sounds you can hear. The infra-sound, what you can not hear, is not measured by administrative authorities.
Some studies that takes into account inaudible infrasound (6Hz) suggest that it does not significantly affect human behavior or health-related factors. Unfortunately, most studies are based on information provided by the manufacturers and do not take into account the actual measured levels which are much louder than anticipated, or for that matter any long-term effect. Some even suggests that health problems are caused by phobia for the turbines; the perception of infrasound risks and the negative expectations people have of wind tubines in itself is thought to create symptoms attributed to the wind turbines, a nocebo effect.
Stronger infrasound levels than expected
Ken Mattsson, Swedish Professor of Computational Science and Gustav Eriksson, PhD are specialists in measurements and the tech used. Professor Mattsson says a whole lot of equpment and models relied heavily upon by experts or governements show incorrect data, something that surprisingly renders very little attention.
“Wind power is an area that generates large amounts of infrasound. In order to check if we have made correct calculations we get out and measure the sound to see if our computer simulations are correct. You do controls, which is why we get outside and do quite a lot of measuring”, he says in Tidslinjen Podcast.
Together with Gustav Eriksson he has now studied exactly how much low-frequency sound emit from these parks, making field-measurements around different wind turbine parks. They found infrasound levels from the wind turbines were on average between 92 och 105 dB at 1 Hz at larger parks close to where people live. These are significant levels. No studies have ever been made on impacts from infrasound this strong or what consequences chronic exposure from this may be.
Finnish Association for Environmental Health has measured infrasound from wind turbines since 2019, showing it can be measured at a distance of at least 30-60 km from the wind parks.
A Swedish otoneurolog and specialist on ear-brain neurology and migraine, Håkan Enbom, comments in an article to Swedish Epoch Times:
“– Infrasound is a form of sound-burden that is difficult to spot as you can not hear it even if it is very strong. It spreads very far and penetrates walls of concrete and even the human body and through the skull and straight into the brain.”
So, unlike normal sound there is no way to protect yourself against infrasound.
The topic is in great need of more research, but while some claim that “if you can not hear it it can not be harmful”, studies of infrasound that have found an associated impact have been made and those show various effects on humans; both physiological and psychological. Chronic Infrasound Impact is thought to cause disturbance of vascular regulation in all organisms. It can disrupt the natural balance of chemicals in blood vessels which can lead to inflammation and it has shown to increase brainactivity, making relaxation difficult and affecting sleep, cause dizziness, increase a sense of unease and discomfort. Exposure to high levels (above 100 dBz) for as little as one hour can negatively impact cardiac muscle contractility, with a decrease in contraction force of almost 9% for every 10 dBz above 100 dBz. Often considered inaudible, infrasound still may disturb sensory cells in the ear, potentially altering their sensitivity and create discomfort in the middle ear. There is also a growing evidence that infrasound may stimulate the vestibular system, potentially causing effects similar to sea sickness. Some people have reported physical sensations; feeling deep humming vibrations in their body or in objects around them when exposed to infrasound.
Environmental Concerns
The impact of wind turbine infrasound and low-frequency noise on insects is an area that has received even less attention compared to effects on humans and larger animals. However, some studies have investigated potential impacts on insects.
The low-frequency noise from the wind turbines can affect insect behaviour, particularly in species that use acoustic communication, and interfere with their signals used for mating calls or territorial defense for an example. Some insects may experience disorientation or show changes in their movement patterns when exposed to infrasound. It has shown to cause stress responses in some species as well as changes in hormone levels and immune function. Some studies suggest that certain insect species may avoid areas with high levels of low-frequency noise, potentially leading to changes in local insect populations and distribution. The disruptions are significant enough to potentially impact reproductive success and population dynamics and may threaten their overall health and survival. If pollinating insects are affected by wind turbine noise, this could have broader ecological consequences, potentially impacting plant reproduction and ecosystem health.
Biodiversity sinks
Wind turbines have other reported negative effects on insect populations and are considered “biodiversity sinks” for insects. A single wind turbine in the temperate zone might kill approximately 40 million insects per year. In Germany alone, it is estimated that the turbines themselves kill 1.2 trillion insects per year. Evidence suggests that hill-topping, swarming, and migrating insects are particularly prone to interacting with wind turbines, the artificial lighting being one pull-factor, and this may disproportionately affect certain insect populations. The loss of these groups of insects may affect the feeding patterns and populations of insectivorous animals, such as bats. For instance, about 20% of insect species consumed by bats killed at wind turbines are agricultural and silvicultural pest insects. Disrupting food webs, the loss of these natural predators could have far-reaching implications, not the least for pest control in nearby agricultural areas.
A study conducted in Sweden found that painting one of the three turbine blades black alone reduced bird fatalities by 70%. This study focused on birds, but the principle could potentially be applied to increase visibility for insects as well.
There is a considerable mismatch between the globally positive claims about wind farms and the pushing for fast tracking the development of wind power technology compared to the gigantic and far-reaching long-term negative consequences for living beings, ecosystem health and biodiversity. Wind turbines are simply not as “green” as proclaimed – they are a significant environmental hazard. We ought to abandon the wind turbine technique and replace it with reliable and truly environment-friendly sources of energy.
Läkartidningen (Swedish): Opinion – Infrasound from Wind Turbine – an overlooked health hazard
Wind-watch.org: Effect on motorway