Kvaerner has awarded global engineering company VSL a contract for the post-tensioning works for the 11 floating concrete hulls for turbines at Equinor’s 88MW Hywind Tampen floating offshore wind farm off Norway.
VSL will be responsible for the post-tensioning works of the semi-submersible concrete structures which will require installation of vertical post-tensioning tendons in the hulls with lengths up to 85 metres.
To speed up the onsite installation, the post-tensioning tendons will be fully prefabricated by VSL and delivered to site ready for installation.
All the post-tensioning operations will be done from the top of the concrete hulls including grouting in a single operation, the company said.
VSL business development manager for wind energy Josep Fabra said: “This pioneering project will serve as a test bed for the future development of wind farms using concrete Spar buoys.
“The use of concrete, the optimised construction process, with almost no maintenance, have allowed Spar buoy foundations for offshore wind turbines to emerge as an efficient solution for deep water sites.
“As the wind market is becoming more important with the acceleration towards the green energy transition, VSL has developed a robust and unique technical solution for challenging installation and environmental conditions.”