Summary of Small Wind Turbine Noise Measurements in dBA

By Paul Gipe

Summary of Small Wind Turbine Noise Measurements at Wulf Test Field in dBA
  Hub Reference Slant     Sound   Projected   Projected
Turbine Height Position Distance SPL   Power   100   to 45 dBA
Tested H Ro Ri @ 8 m/s @ 10 m/s @ 8 m/s @ 10 m/s @ 8 m/s @ 10 m/s @ 8 m/s @ 10 m/s
  m m m LAeq, ref LAeq, ref LWA, ref LWA, ref LAeq LAeq m m
Ampair 100
Charging 13.4 13.9 19.3 44 51 na na na na na na
Unloaded 13.4 13.9 19.3 49 56 80 86 32 38 50 75
Air 403 13.4 14.0 19.4 57 60 88 91 39 43 50 75
BWC 850
Charging 19.2 20.4 28.0 48 53 82 87 34 39 22 45
Unloaded 19.2 20.4 28.0 58 64 92 97 44 49 80 150
Ln= ambient, turbine parked.
Ls+n= ambient plus wind turbine operating.
Ls= wind turbine noise alone at reference postion Ro
Ls= LAeq, ref, corrected level
Atmospheric absorption=0.005 dB/m