Ørsted has developed a new, lower-noise installation method for offshore wind foundations. The new technology has been tested in Germany, proving that this approach can reduce noise levels during foundation installations, strengthening existing protections for marine life.
At the German offshore wind farm Gode Wind 3, Ørsted tested the installation method on three monopile foundations. The noise mitigation method involves a patented jetting technology attached to the monopile, which lowers the resistance of the surrounding sandy soil, effectively allowing the foundation to sink into the seabed—completely replacing conventional installation methods such as pile driving. The implementation of the new installation technology has resulted in a substantial decrease in underwater noise levels: with a reduction of 34 decibels relative to the most commonly used installation method, and without additional mitigation, noise levels were reduced by over 99 percent to a level just marginally above the ambient noise found in the German Bight in the North Sea.
Ørsted carried out the installation together with Jan De Nul Group and their installation vessel Les Alizés, as well as contractor Aarsleff. Ørsted has been developing the technology over the past years and is now looking into how to introduce the technology into the future pipeline, which includes assessing the feasibility of the method on more complex ground conditions than the pure sand conditions found at the Gode Wind 3 site. Further regulatory approvals will also be needed before the technology can be implemented in other markets globally.
