The credibility of the GPG is undermined by the failure of the IoA to provide an evidence- based defence of the guidance. [...] 1.3 We consider that there are two fundamental problems with the IoA Supplementary Guidance, firstly the treatment of wind shear in Supplementary Guidance Note 4, where the IoA proposes two conflicting methodologies for measuring the wind speeds which are used to assess the noise impacts and to set the noise condition limits for a wind farm. [...] 5 3.12 However, the plot is based on two unfounded assumptions: (i) that the microphone is equally downwind of all the turbines when the wind direction is within the +/- 15o arc; and (ii) that all turbines experience the same wind speed when the wind direction is within the +/- 15o arc. [...] Test of the accuracy of the IoA GPG recommended parameters in predicting turbine noise levels 3.27 We have been able to obtain data to test the accuracy of the IoA GPG recommended sound power levels and ground factor in predicting turbine noise levels near to the single turbine located at Sporle Road in Swaffham. [...] The results of these surveys are used to determine the noise impacts of the proposed development and dictate the noise levels set in the wind farm noise condition.
- Pages
- 37
- Published in
- United Kingdom
