Over the course of five years, a team of researchers from Flinders University in Australia carried out a comprehensive study to assess the effects of both wind farm and road traffic noise on sleep quality. Led by sleep and acoustics experts, the study covered 460 sleep study nights and included 68 participants from diverse living environments, such as areas near wind farms and busy suburban roads and quieter rural settings.
To replicate real-world conditions, the researchers exposed participants to both wind farm and road traffic noise at different sound pressure levels while they slept in a controlled laboratory environment. The study involved direct sleep assessment using electroencephalography (EEG), along with hearing evaluations and various daytime listening tests.
Debunking the myth
The findings revealed that both the whooshing sound of wind farms and road traffic noise have the potential to cause minor sleep disruptions. The level of disturbance is largely dependent on the volume of the noise and the depth of a person’s sleep at the time of exposure. Interestingly, at the highest exposure level, road traffic noise was more disruptive to sleep than wind farm noise.
Furthermore, the study explored the effects of wind farm infrasound on sleep. Infrasound refers to sound waves with frequencies that fall below the human hearing range. At realistic levels, wind farm infrasound was found to be inaudible to the human ear and did not disrupt sleep. This aligns with previous research, indicating that infrasound is unlikely to be the cause of noise complaints about wind farms. Instead, other low-frequency audible sounds, like rumbling and thumping, should be examined further to better understand the effects of wind farm noise on sleep.
The results of the study were presented at the International Conference on Wind Farm Noise in Dublin on June 22, 2023, and are pending a peer review for publication in a scientific journal.
Dispelling fears
Flinders University study adds to the growing body of evidence that wind farm noise is no more disruptive to sleep than road traffic noise. These findings are crucial for policymakers, renewable energy developers, and communities near wind farms. However, additional research is necessary to address the concerns of noise-sensitive individuals and to explore other low-frequency sounds that may impact sleep quality.