Virtually anything with moving parts will make some sound, and wind turbines are no exception. Well designed wind turbines are generally quiet in operation. Wind turbine noise is very low compared to the noise from road traffic, trains, aircraft and construction activities and can also be compared to the sound level inside a typical living room, the reading room of a library or in an unoccupied, quiet, air-conditioned office. Typically, the sound of a working wind farm is actually less than normal road traffic or an office.
Evaluation of Wind Turbine Noise
DeGagne, D.; Lewis, A.; May, C. (2002). Evaluation of Wind Turbine Noise. Canadian Acoustics , 30(3), 82-83.