Noise prevention (bubble curtain)

During the construction of wind farms, so-called tripods need to be pile-driven into the seabed to anchor the foundations for wind turbines, which can reach as high as 150 metres. This results in significant underwater noise emissions, which can cause harm to marine mammals – especially porpoises.

Trianel first to use “large bubble curtain”

Trianel began research on noise prevention early on and identified the “large bubble curtain” as an ideal method of noise reduction. In a research project sponsored by the Federal Ministry for the Environment, Trianel has, together with the company Hydrotechnik Lübeck, further developed the bubble curtain to meet the special requirements related to the construction of tripod foundations. In addition to efficient noise reduction, the research project also aimed at making “serial” application of the large bubble curtain without any negative impact on the highly complex construction process possible.

How it works

To create the bubble curtain, each foundation is first encircled by a perforated tube. The tube is then filled with compressed air which rises toward the surface, forming a circular wall of bubbles. During pile driving operations, this wall of bubbles completely encloses the source of the noise, thus reducing its propagation. This simple principle is so successful that the large bubble curtain is now being used in almost all ongoing offshore construction projects.