Innovative approaches for reducing wind turbine noise: A review from mechanical and aerodynamic perspective

Although wind energy is considered as one of the cleanest forms of energy, the noise generated from wind farms, if not mitigated, adversely affects the nearby environment resulting in several hearing problems. Hence, this research provides a systematic comparison among different noise reduction techniques to find out the best wind turbine modification for better noise reduction. Active noise cancellation (ANC), among adaptive methods has the potential to reduce noise by 35.71 % without affecting the aerodynamic performance of the turbines. Among blade modifications, literature reveals that sinusoidal trailing edge (TE) and TE serrations are expected to reduce the aerodynamic noise by 29.13 % and 28.41 % respectively. A strong correlation was observed between the noise reduction by blade modifications and the corresponding lift-to-drag ratio of turbines. Among different regression model, cubic regression provided the best result with an R-squared value of 85.90 %. The model predicts that TE serrations have the potential to increase the lift-to-drag ratio by 0.41 % while reducing the noise by 28.41 %, making it the most attractive blade modifications for noise reduction in combination with the ANC. The proposed configuration, if implemented, will significantly reduce the wind turbine noise without affecting the its performance ensuring a sustainable future.