South Australia Study finds Infrasound from Wind Farms Not a Concern

The Environment Protection Authority of the state of South Australia has released a new study comparing infrasound from wind farms–one of the favorite bugaboos of anti-wind groups–with that from other everyday sources. The research effort concluded that wind turbine infrasound is “insignificant in comparison with the background level of infrasound in the environment.”

The study, performed by consulting firm Resonate Acoustics, took measurements over a period of approximately one week at seven locations in urban areas and four locations in rural areas, including two residences approximately 1.5 kilometers (0.9 miles) away from the wind turbines.

The Climate Spectator website has an excellent summary, titled “Cause of wind turbine syndrome goes missing.” In addition, here are a few choice quotes from the study itself:

Under “Urban Environments”:

“Noise generated by people and associated activities within a space was one of the most significant contributors to measured infrasound levels, with measured infrasound levels typically 10 to 15dB(G) higher when a space was occupied. Infrasound levels up to approximately 70dB(G) were measured in occupied spaces.”

“At two locations, the EPA offices and an office with a low frequency noise complaint, building air conditioning systems were identified as significant sources of infrasound. These locations exhibited some of the highest levels of infrasound measured during the study.”

Under “Rural Environments”:

“Infrasound levels at houses adjacent to wind farms (Locations 8 and 9) are no higher than those at houses located a considerable distance from wind farms (Locations 10 and 11). For example, the outdoor infrasound levels at Location 8 are significantly lower than those at Location 11, despite the house being located much closer to operational wind turbines (1.5 kilometres compared to 30 kilometres).”

“Infrasound levels in the rural environment appear to be controlled by localised wind conditions. During low wind periods, levels as low as 40dB(G) were measured at locations both near to and away from wind turbines. At higher wind speeds, infrasound levels of 50 to 70dB(G) were common at both wind farm and non-wind farm sites.”

“Organised shutdowns of the wind farms adjacent to Location 8 and Location 9 indicate that there did not appear to be any noticeable contribution from the wind farm to the G-weighted infrasound level measured at either house. This suggests that wind turbines are not a significant source of infrasound at houses located approximately 1.5 kilometres away from wind farm sites.”

Under “Summary of results”:

“This study concludes that the level of infrasound at houses near the wind turbines assessed is no greater than that experienced in other urban and rural environments, and that the contribution of wind turbines to the measured infrasound levels is insignificant in comparison with the background level of infrasound in the environment.”

Source: AWEA

For more information on: AWEA