Noise mitigation measures implemented by Ørsted during offshore wind farm construction have entailed use of bubble curtains or other noise barriers during traditional installation. A new wind farm construction method now allows the company to further reduce the potential impact from such activities on the marine environment and build in a more cost-effective way.

The technique involves a patented jetting technology attached to the monopile, which lowers the resistance of the surrounding sandy soil. This mechanism effectively allows the foundation to sink into the seabed without reliance on conventional installation methods such as pile driving.

When tested on three monopile foundations at the 242 MW Grode Wind 3 wind farm in Germany, the new installation approach resulted in a substantial decrease in underwater noise levels. A reduction of 34 decibels relative to the most commonly used installation method was documented for a noise level decline of over 99%. The resulting noise levels were just marginally above the ambient noise common in the German Bight in the North Sea.

The new jetting technology has been successfully tested the 242 MW Gode Wind 3 offshore wind farm in Germany, proving the approach can dramatically reduce noise levels during foundation installations, strengthening existing protections to marine life and potentially paving the way for the next generation of monopile foundations.

Beyond noise mitigation, the new technology can provide for more efficient and cost-effective installations of offshore wind foundations. The process was used to complete the installation of 11 MW turbines on top of the foundations, and Gode Wind 3 is expected to start commercial operation later this year.