Wind Energy – Kaskasi
A world-first kicks off at Kaskasi! The innovative ‘collared monopile’ design, which is based on an RWE patent, is being premiered at the offshore wind farm, Kaskasi, in the German North Sea.





This refers to special collars being installed around the monopile foundation at seabed level – a process which has just been completed at Kaskasi.
“It’s a great credit to the project team and our contractors that we developed, manufactured and safely installed the three innovative foundation collars”, emphasises Sven Utermöhlen, CEO Offshore Wind at RWE Renewables.”
“The collared monopile, a patented solution developed in-house, will help to increase stability in difficult ground. This showcases our technical expertise as the second largest player in offshore wind globally”, he adds.
Kaskasi is RWE’s sixth wind farm off the German coast, the 342-megawatt project is currently under construction 35 kilometres north of the island of Heligoland. In total three innovative foundation collars were successfully embedded into the seabed – each 7metres high, weighing 170 tons.
The installation in water depths of up to 25 metres was carried out by DEME’s jack-up vessel Sea Challenger. The space between collar and monopile foundation was filled with grout material, creating finally a stable connection.
RWE will carry out accompanying tests to verify that the collar improves the structural behaviour in comparison with standard monopiles.
Bas Nekeman, Business Unit Director Northern Europe at DEME Offshore, emphasises: “Whilst these monopile foundation collars represent only a relatively small scope of work DEME Offshore is performing at the Kaskasi offshore wind farm, we are extremely happy achieving this important milestone for the project. The installation of these type of structures is a world’s first which required us to develop a tailor-made solution. The completion of the three monopile foundation collars demonstrates our ability to deliver our customers the right technical know-how, operational excellence and team spirit required for the successful delivery of these types of innovative projects.”