Audibility of wind farm infrasound and amplitude modulated tonal noise at long-range locations

Wind energy is one of the fastest growing sources of renewable energy in Australia. However, wind farm noise (WFN) continues to attract complaints from residents living near wind farms, including from residents who live relatively long-distances (>1 km) away. Here we use a computational approach to assess the audibility of infrasound and amplitude modulated (AM) tones at long-range locations. Our approach considers the uncertainty associated with WFN measurements and human hearing variability. We show that infrasound is not audible to residents with normal hearing who live at distances greater than 1 km from a wind farm, but the measurements at one wind farm showed that AM tones occurring at low frequencies may be perceived up to distances of 9 km. Although these results from South Australian wind farms may not be reflective of other wind farm settings, these results support that AM tones could be the main reason behind WFN complaints at long-range locations, and thus warrant further attention to help make wind farms more acceptable to impacted residents.