With the increasing number of operational wind farms/turbines, the requirement for noise measurements
required to demonstrate compliance with planning conditions is increasing as well. The British ETSU-R-97
noise limits are often set relative to measured or standardised 10 m height wind speeds and therefore the
assessment of noise from wind turbines requires simultaneous noise and wind speed/direction measurements.
For financial reasons, smaller and single turbine sites are often not equipped with a meteorological mast. If no
independent hub height wind measurements are available, wind speed is either taken from nacelle
anemometers or derived from power measurements combined with the power curve for the respective wind
turbine type. Noise measurements referenced to nacelle anemometer data will be compared with the same
measurements but correlated with derived power curve wind speed, and measured wind data from separate
met mast or other remote sensing devices. The influence of incorrect filtering of wind data for shadow effects
(mast and/or nearby wind turbines) on the noise assessment may be presented, depending on how much time
is available. The advantages and disadvantages of the various methods will be discussed.