Proper mitigation measures do work.

German Offshore Wind Companies Submit Noise Mitigation Research Report

Each of the noise mitigation systems manufactured as prototypes withstood the harsh conditions at sea and demonstrated the noise mitigating effect. When corrected for site-specific effects, the mitigation effect totalled up to nine decibel in the relevant range. This brought the noise level much closer to the noise emission limit of 160 decibel at a distance of 750 meters around the source of the noise. More research and development work is required on the basis of the ESRa project in order to meet the limit reliably in the future.
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(The Test Rig)

"The offshore wind industry takes the protection of the environment very seriously when building and operating offshore wind farms. Basic research like the ESRa project is extremely important for a better understanding of the effects on the maritime environment and to initiate further measures", explained Jörg Kuhbier, Chief Executive Officer of Stiftung Offshore-Windenergie (Offshore Wind Foundation).

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