Last update: June 23, 2017

The Australian February 24, 2015 Australia

Canadian research boosts Cooper’s case on turbines

Acoustics expert Steven Cooper has expanded his legal action to include vocal wind farm advocate Simon Chapman, as independent research was produced to support the findings of high-level infrasound at Cape Bridgewater in Victoria.

By Graham Lloyd, Environment Editor, Sydney

The Australian yesterday reported Mr Cooper was considering legal action against the ABC’s Media Watch and its portrayal of him and his research on the effect of the Pacific Hydro wind turbines on local residents.

Participants in the Cape Bridgewater study, which was designed and financed by wind farm company Pacific Hydro, are considering joining the legal action against Professor Chapman over published comments which questioned their integrity.

Professor Chapman, from the University of Sydney completed his PhD on “Cigarette Advertising as Myth; A Re-Evaluation of the Relationship of Advertising to Smoking”.

He has argued that health complaints by some residents living near wind farms are the result of psychological concerns rather than physical impacts.

In an article published on The Conversation website and highlighted by Media Watch, Professor Chapman said the six residents involved in the study “rush to their diaries to report ‘sensations’ when they are cued by audible changes in the sound?”.

“No chance of any collusion in such a study when these six would all know each other, and half actually lived together,” he said.

“If this dog’s breakfast of a study means anything, it provides support for the nocebo hypothesis; those with pre-existing anx­iety and antipathy to the turbines, when cued by audible sound from those turbines, record ‘sensations’ on cue.”

But Mr Cooper said the findings of the Cape Bridgewater study did not focus on audible noise and that the infrasound that was recorded was inaudible.

He said residents were able to record changes in “sensations” which matched changes in the wind turbine operations which were measured separately. For the majority of the observations of high sensation severity, there was no change in the noise.

The Cooper study results have been hailed as significant by some of the world’s leading acoustic experts but not accepted as proving a cause and effect relationship by Pacific Hydro.

Mr Cooper has received further support for his work at Cape Bridgewater from computer scientists in Canada who have been working to record sub-audible noise or infrasound from wind turbines since 2013.

Richard Mann, at the University of Waterloo in Ontario, said scientists there had arrived at a similar position to Mr Cooper despite working in a different way.

“Our results show that wind turbines emit a characteristic pulsation (change in barometric pressure) that repeats with every blade passage,” Professor Mann said.

“This is consistent with the infra sound ‘signature’ you have reported.”

The Waterloo University research did not consider health effects from wind turbine infrasound. But Professor Mann said: “I join the many scientists and experts worldwide requesting a thorough investigation of wind turbine noise.’’

Letter by Professor Richard Mann to Mr Steven Cooper

21 Feb 2015

Re: Cape Bridgewater noise study

Mr. Steven Cooper, INCE, AAS, ASA
The Acoustics Group Pty Ltd
20-22 Fred Street
Lilyfield, 2040, NSW, Australia

Dear Steven Cooper,

I am a professor at the University of Waterloo in Ontario, Canada. Since August 2013 I have been working with a colleague to research methods for measuring infra sound emitted by wind turbines.

I commend you on your excellent research on wind turbine noise. Your “On”/”Off” curves clearly show the low frequency noise and vibration that Wind Turbines produce.

The focus of our research has been to quantify/measure infra sound. To do this we needed to separate turbine generated noise from wind noise. We also needed to isolate a single wind turbine from nearby turbines and other sources of noise. My colleague and I have developed a method to do this. We will present our results at Wind Turbine Noise 2015 in Glasgow Scotland, in April of this year. A draft of this paper is available online at:
https://uwaterloo.ca/audio-research-group/sites/ca.audio-research-group/files/uploads/files/coherent_wt_measurement_0.pdf

We use an optical telescope fitted with a photodetector, aimed at the turbine. Each time a blade passes through the field of view, brightness changes are detected, and recorded along with the input sound. Infra sound is found by averaging the input sound over repeated blade passes, thereby identifying infra sound from an individual turbine.

Wind turbines emit a characteristic acoustic pulse (air pressure change) that repeats with every blade passage. We report pressure changes of approximately 0.1 Pa (Pascals, peak to peak levels) with one turbine reaching 0.3 Pa. We present results from six different wind farms in Ontario, where we have isolated noise from a single turbine.

My personal opinion is that governments and the wind industry have failed to address infra sound from Wind Turbines. They are remiss in claiming no harm to health when they only measure audible sound and ignore the infra sound.

I am advocating that governments and wind companies acknowledge the known health impacts of infra sound, determine safe exposure levels, and establish proper measurement standards.

I welcome contact from yourself and other interested researchers and will be happy to answer any questions, to assist others in replicate our results, and therefore contribute the common knowledge base.

Richard Mann, Associate Professor
School of Computer Science
Faculty of Mathematics
University of Waterloo
200 University Avenue West
Waterloo, Ontario, Canada

Download the letter