Assessment of the Noise generated by Wind Turbines at low Frequencies

The noise production from wind turbines (WT) and its propagation into the surrounding environment have an impact on the receptors (RC) that have to be accurately predicted within the environmental impact assessment. The low-frequency noise (LFN) is of special concern for it is typical of wind systems and it involves specific computational issues. The purpose of this study is to apply and compare the assessment procedures currently used in different European countries for the prediction of LFN produced by wind turbines, with reference to a specific case. The results of the calculations for a planned wind farm in northern Sardinia, Italy, obtained by the available computational tools and with the help of the presented predictive models are presented and discussed. It can be deduced from this that the impact due to the low frequencies noise generated by wind turbines in the vicinity of sensitive receptors is negligible in terms of generated sound pressure levels (SPLs), even though further investigations on such a topic are needed.