Determination of Acoustic Compliance of Wind Farms

Abstract

An issue exists around the world of wind farms that comply with permit conditions giving rise to noise complaints. Approval limits are normally expressed in A-weighted levels (dB(A)) external to residential receivers. The distance from the wind farm to residential receivers can result in difficulty in establishing the dB(A) contribution of the wind farm, as the overall noise includes background noise that can provide masking of the wind turbine noise. The determination of the ambient background at a receiver location (without the influence of the wind farm) presents challenges, as the background level varies with the wind and different seasons throughout the year. On-off testing of wind farms does not normally occur at high wind farm output and limits this approach for acoustic compliance testing of a wind farm. The use of a regression analysis method developed more than 20 years ago is questioned. Anomalies with respect to compliance procedures and the regression method of analysis based on real-world experience are discussed.

Cumulative Impact of Wind Farm Noise

“…A number of authors have mentioned infrasound as a noise-related issue resulting from the wind farm operation [14][15][16][17][18][19][20], while some others are more concerned with lowfrequency sound [21]. In their comprehensive study of literature on the possible effects of wind farms on the health of the population, Freiberg et al [22] conclude that when it comes to infrasound and low-frequency noise produced by turbines in wind power plants, major impacts on people include physical symptoms, general health issues, and affective impact (temper).…”