Research from Flinders University indicates that noise from wind farms might not be as harmful to sleep as road traffic noise.
One of the main complaints people tend to have about wind farms is that they produce a lot of noise. A Flinders study from August 2021, as reported by Renew Economy, found that the ‘swoosh’ noise wind turbines make is more noticeable to residents living nearby at night.
And now, a new study has found that, while wind farm noise is still noticeable when sleeping nearby, it’s no more harmful to sleepers than putting up with road noise.
“In order to capture the most representative wind farm noise features and levels, we used noise samples from long-term measurements of wind farm noise,” Doctor Bastient Lechat said.
“These were then reproduced in the sleep laboratory to replicate real-life noises in a much more controlled environment than is possible in field studies, where wind and noise conditions are highly variable. The study included direct sleep measurements using electroencephalography as well as hearing tests and a range of daytime listening tests.”
Here’s how the team did the research: taking 20-second audio samples from a wind farm and a busy road, sampling the sites at three different times of the day, the team measured how disturbed participants were when the sounds were played while they were sleeping.
During a separate test, 3-minute audio samples were used, including very low-frequency wind farm infrasound. At realistic levels, the infrasound was not found to produce any sleep disturbance.
68 participants over 460 nights were part of the test. Each participant spent seven consecutive nights at a sleep laboratory, and participants included those living near wind farms, those living near busy roads, and those living in quiet areas.
The overarching discovery of the experiment, according to sleep expert Professor Peter Catcheside, was that both road and wind turbine noise disrupts sleep, depending on the loudness and the depth of sleep the participant was at.
“However, at realistic levels, these effects were quite small. We also found no evidence to suggest that wind farm noise is any more disruptive to sleep than road traffic noise. At the highest exposure level, road traffic noise was a little more sleep disruptive than wind farm noise,” Catcheside said.
“Our results align with previous studies and showed that infrasound played at realistic levels was not audible during wakefulness and produced no detectable changes during sleep. Infrasound is therefore unlikely to explain noise complaints from wind farms, suggesting that other low-frequency audible rumbling and thumping components deserve more attention towards better understanding wind farm noise effects on sleep.”
Catcheside added that while this research obviously doesn’t rule out that some people can be particularly noise-sensitive around wind turbines or busy roads, it does provide evidence that wind turbines are no more disruptive to sleep than road noise.
This research was presented at the International Conference on Wind Farm Noise in Dublin, and is yet to be peer-reviewed.