At the planning board meeting of April 13, 2011 Clif Schneider pointed out another problem with Acciona’s noise studies and wind turbines noise.
Acciona/ Hessler omitted important information and misrepresented their own protocol for estimating background sound levels. As a result Acciona/ Hessler used an elevated background sound level to design their wind farm allowing turbines to be placed much closer to non-participants and allowing noise levels that exceeded NYSDEC guidelines.
Schneider was interested in seeing how much sound Acciona's turbines made at low wind speeds because he believes wind turbines sounds are more noticeable and annoying at low wind speeds. Tim Conboy, Acciona’s Development manager, refused to release low-speed sound data stating that it was unreliable. Fortunately for Cape Vincent, Acciona's turbine test data was available from another source on the web.
You can see by inspecting the data points in the plot in the WIND Test report that sound levels below 6 m/s actually fit closer to the curve than at higher wind speeds. It also looks like Conboy was using reliability as an excuse to deny access to the information.
There should be reliable sound levels at low wind speeds, only because this is the heart of Hessler's approach -- to find the maximum difference between the sound of a turbine and background sound.
Schneider maintains that instead of designing the St. Lawrence Wind Project around background sound levels associated with 6 m/s winds (e.g., 37 dBA), Acciona/Hessler should use the lower background sound level associated with 5 m/s winds (e.g., 34 dBA), because maximum difference occurs at 5 m/s.
He is also concerned with the variability of Acciona's turbine sound levels. It is impossible to determine what the sound variation is between turbines by testing a single turbine at one specific location. You can only understand the difference in sound levels between two or more turbines by sampling more than a single turbine. If the single turbine that Acciona tested happened to be the quietest turbine to come off their assembly line, then using that data may underestimate sound levels for all others. This may explain some of the problems at Waubra, AU.
Schneider concluded that this issue is important only because it highlights the dishonesty of Acciona and Hessler. His own studies have shown that background sound levels in Cape Vincent are 25 dBA, far quieter than either 37 or 34 dBA asserted by Acciona/Hessler. “To protect our community setbacks between Acciona's turbines and non-participants in Cape Vincent have to be moved back - way back”, Schneider said.
~~~~~~~~~~~~~
Link here to read Mr. Schneider's letters to Acciona and cape Vincents Planning Board and Acciona's response to Mr. Schneider
Wind Test Documents~
Acciona/ Hessler omitted important information and misrepresented their own protocol for estimating background sound levels. As a result Acciona/ Hessler used an elevated background sound level to design their wind farm allowing turbines to be placed much closer to non-participants and allowing noise levels that exceeded NYSDEC guidelines.
Schneider was interested in seeing how much sound Acciona's turbines made at low wind speeds because he believes wind turbines sounds are more noticeable and annoying at low wind speeds. Tim Conboy, Acciona’s Development manager, refused to release low-speed sound data stating that it was unreliable. Fortunately for Cape Vincent, Acciona's turbine test data was available from another source on the web.
You can see by inspecting the data points in the plot in the WIND Test report that sound levels below 6 m/s actually fit closer to the curve than at higher wind speeds. It also looks like Conboy was using reliability as an excuse to deny access to the information.
There should be reliable sound levels at low wind speeds, only because this is the heart of Hessler's approach -- to find the maximum difference between the sound of a turbine and background sound.
Schneider maintains that instead of designing the St. Lawrence Wind Project around background sound levels associated with 6 m/s winds (e.g., 37 dBA), Acciona/Hessler should use the lower background sound level associated with 5 m/s winds (e.g., 34 dBA), because maximum difference occurs at 5 m/s.
He is also concerned with the variability of Acciona's turbine sound levels. It is impossible to determine what the sound variation is between turbines by testing a single turbine at one specific location. You can only understand the difference in sound levels between two or more turbines by sampling more than a single turbine. If the single turbine that Acciona tested happened to be the quietest turbine to come off their assembly line, then using that data may underestimate sound levels for all others. This may explain some of the problems at Waubra, AU.
Schneider concluded that this issue is important only because it highlights the dishonesty of Acciona and Hessler. His own studies have shown that background sound levels in Cape Vincent are 25 dBA, far quieter than either 37 or 34 dBA asserted by Acciona/Hessler. “To protect our community setbacks between Acciona's turbines and non-participants in Cape Vincent have to be moved back - way back”, Schneider said.
~~~~~~~~~~~~~
Link here to read Mr. Schneider's letters to Acciona and cape Vincents Planning Board and Acciona's response to Mr. Schneider
Wind Test Documents~
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