The study was commissioned by Natural Resources Canada (NRCan) after Daniel d'Entremont complained infrasound from the turbines, one of which is located about 330 metres from his house, caused fatigue, headaches, sleep disturbance and other health impacts in family members severe enough to drive them from their home. NRCan provided funding to the Pubnico Point project through its wind power production incentive program.
But measurements by HGC Engineering found infrasound is not a concern. "Sound at infrasonic frequencies is not present at perceptible levels near the wind turbine generators nor at the d'Entremont residence and it is concluded that infrasound is not an issue. This conclusion agrees with internationally recognized research on the low frequency sound produced by wind turbine generators," the report concludes.
HGC also looked at levels of audible sound at the d'Entremont residence and, because Nova Scotia has no technical guidelines for assessing the sound impact of wind turbines on residences, assessed those against limits in Ontario, which is the only province in Canada with noise assessment guidelines specific to wind turbines.
"The sound of the wind turbine generators is continually audible at the d'Entremont residence, but much of the time is not appreciably above the numeric criteria derived under the guidelines," the report says. "However, under certain wind and atmospheric conditions -- most notably when there are light winds from the south and the humidity is high -- the sound level impact of the wind turbine generators is significantly greater than the background sound levels."
NRCan's Jimmy Royer says his department is working with the wind farm's owner on mitigating turbine sound under those conditions. "At this point it is too early to state what these actions will be and when they will be applied."