Comparative Environmental Assessment of Wind Energy Projects: Acoustic Load

Abstract

Purpose. Comparative environmental assessment of wind energy projects from the perspective of the potential acoustic load on the environment: compliance with permissible values, specificity of propagation and optimization of siting. Methods. Analysis and synthesis of information, field research, cartographic and mathematical modelling. Results. In the most part of the study area, the background noise level reached rather high values, higher than the «comfort» level of 45 dB. The simulation of sound propagation from the wind turbine showed an attenuation to a value of less than 20 dB at a distance of 2 kilometers. The resulting acoustic load was calculated for the points referring to the buildings of the nearest settlements (for the case of installing the Enercon E-40 and Enercon E-115 wind turbines). The calculations of the resulting sound levels make it possible to state that the acoustic effect of the wind turbines in both siting strategies is 15-20 dB lower compared to the background noise level, the main component of which is wind noise. The excess of noise level was 5 dB for Enercon E-115, and 8-9 dB for Enercon E-40. Conclusions. According to the type of wind turbine, the noise level may overlap with the background level and produce a relatively less acoustic impact on the local population. Even in case of the extensive wind energy development strategy, the total noise levels will not exceed the background levels within the model site.