RWE, together with Hydrotechnik Offshore, has successfully implemented an innovative underwater noise reduction technology—known as a bubble curtain—for offshore wind farm construction in the United Kingdom. This solution is designed to protect marine life from the noise generated during offshore wind energy development. This groundbreaking solution was deployed at the Sofia offshore wind farm, located 195 km off the coast of England.

How does the bubble curtain work?

According to RWE, the bubble curtain—already in use across Europe—reduces the spread of underwater noise by creating a barrier of rising bubbles around the turbine installation site. By dampening sound waves, this technology mitigates disturbances to marine species such as harbour porpoises, dolphins, and whales, which rely on echolocation to navigate.

The system works by placing a perforated hose on the seabed in a 180-meter-wide ring around the turbine installation site. Compressed air is pumped through the hose, producing a continuous stream of bubbles that rise to the surface. This bubble barrier effectively breaks and slows down sound waves, significantly reducing noise levels during piling operations.

Matthew Swanwick, RWE’s Sofia Project Director, stated: “By trialing the use of a bubble curtain, we are reinforcing our commitment to environmental responsibility. Projects like this can ensure the sustainable development of offshore wind with minimal impact on marine life—especially important given we are working within a Special Area of Conservation.”

The bubble curtain is not the only sustainability innovation at the Sofia offshore wind farm. The project also stands out for using recyclable wind turbine blades: 50% of Sofia’s 100 turbines will be fitted with recyclable blades—the highest proportion ever deployed in a large-scale wind farm.

Additionally, the project will deploy two of the world’s first service operation vessels powered by methanol and batteries, reducing CO? emissions by up to 10,000 tonnes per year.

Sofia is also delivering on its commitment to marine conservation through charitable contributions, including a £25,000 donation to North Sea Conservation, the charity behind the Whitby lobster hatchery, and approved funding for Clean Planet UK to remove abandoned fishing gear from the sea.

Currently under construction at Dogger Bank—195 kilometers from the nearest point on the northeast UK coast—the Sofia offshore wind farm will feature 100 Siemens Gamesa 14 MW offshore turbines. Once operational in 2026, the project will have a capacity of 1.4 GW, enough to power the equivalent of 1.2 million typical UK homes.