A new study commissioned by renewable energy provider Pacific Hydro reveals a trend between wind farm infrasound and sensations reported by a sample of residents. The company arranged an industry-first report taking into how people’s senses are affected by its wind farm located in south west Victoria.
Located near Portland, The Cape Bridgewater wind farm has been operating for six years.
In that time, there have been claims by people in nearby households that the turbines have been causing sensations, including headaches, ringing ears and chest pressure.
In an eight week study titled ‘The Results of an acoustic testing program – Cape Bridgewater Wind Farm’, The Acoustic Group conducted a noise monitoring study to further investigate residents’ concerns.
Diaries of ‘sensations’
Six locals were asked to meticulously diarise their observations.
They were asked to make entries every one to two hours, recording their awareness to levels of noise, vibration and ‘sensations’.
Each participant recorded symptoms such as ear aches, blurred vision and headaches, symptoms they say were heightened when there were strong winds and the turbines were operating at maximum power.
They all claimed these symptoms eased or disappeared when the turbines were shut down.
All of them also recorded feeling anxious and having difficulty sleeping.
Nose bleeds, heart palpitations, pain in bones, breathlessness and stimulation of the bladder and bowels were other impacts noted.
‘Resident Two’ noted that a westerly wind was most detrimental to the family’s health.
“There appeared to be a direct correlation between the operation of the wind facility at Cape Bridgewater and the cluster of symptoms which we suffered as a result of being in the vicinity and the location of our house,” they wrote.
“On the days the wind facility was not operating and especially during the planned shutdown we were exceptionally well, feeling light and energetic, clear in the mind and happy.”
Measuring noise, not medical impacts
The Acoustic Group was conducting a noise test, not a medical report.
An acoustic study of low and infrasound frequencies – using narrow band analysis – found a correlation between noise with wind speed.
It revealed a pattern of infrasound frequencies at the Cape Bridgewater Farm, and around the residents’ homes, when turbines are operating.
The report’s acoustician, Steven Cooper, says the team took many variables into account when measuring the noise of the wind farm.
“During that period we measured operation of the wind farm under different conditions, wind directions, wind speed, and also, at times when the wind turbines were off, when there was no wind,” Mr Cooper said.
“When we started putting the diary information together with the wind farm information and the noise information, we found there were certain conditions of the operation of the wind farm that agreed with the observations where they recorded high sensation levels.”
Previous scientific reports have discredited the theory that infrasound can be heard by the human ear.
In releasing the report, Pacific Hydro’s executive manager of external affairs, Andrew Richards, said the report highlights the need for a “scientifically robust study”, taking into account that the research was based on such a small sample.
Mr Richards said the study does not prove that the symptoms are directly caused by infrasound frequencies.
“There’s not enough data to confirm a correlation,” he said.
“There’s no link between the wind farm and the medical complaints.”
Study highlights the need for more research: report author
Mr Richards said while Pacific Hydro has been compliant with noise regulation standards set by the Victorian Government, the study aimed to go further to address concerns raised by local residents.
“If others want to pick up this work and take it further, particularly a federal agency, I notice today the National Health and Medical Research Council is talking about doing such a study, and we’d welcome that and we would participate in that should we be required,” he said.
The report’s author, Mr Cooper, said the study provides a good basis for further investigation into health impacts.
Mr Cooper says other studies have failed to take into account how peoples’ senses are affected.
“There has never been ‘sensation’ included in questionnaires,” he said.
“The description of noise doesn’t explain what the residents are feeling.
“Previously they were complaining about the noise, but it wasn’t really the noise – it was sensation.”
The report concludes better equipment is needed to look at the different types of sound produced by the turbines from several locations.
Mr Cooper says monitoring techniques tested in the research could be used in further studies.
“What is really exciting is that we found a pattern in special signature that exists when the turbines are operating and does not exist when the turbines are off.
“You can use that signature to commence the medical studies.
“We don’t have a correlation in terms of medical… but we have uncovered a tool which can now lead the next step to be done, because you couldn’t do the medical studies without the acoustic information saying what was going on.”
Pacific Hydro has sent the report to government departments, Members of Parliament, environmental organisations and health bodies.
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The report may be downloaded from the following links:
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