Abstract
The increasing prevalence of wind power across the globe has led to a growth in the number of wind turbines in proximity to human settlement. As a result, the sound level impact from wind turbines has become a fairly contentious issue in some areas. The audibility of wind turbine generators is often a factor of low background sound levels, which in rural environments are dominated by natural sounds. Thus, HGC Engineering has considered ambient sound levels as part of a number of acoustic audits and assessments for existing and proposed wind farms. This paper investigates the variability of wind induced background sound levels in various rural areas by comparing sound level measurements conducted by HGC Engineering in Canada, the United States, and Central America with the reference background sound levels presented by the Ontario Ministry of the Environment (MOE). Specific consideration will be given to the effects of topography and the relationship between hub height wind speeds and ground level wind speeds. This analysis of actual wind induced background sound levels provides a better understanding of the sound level impact from wind turbines in varying rural environments.