GustoMSC and NOV Lifting & Handling have developed the Sjøhest wind blade installation (WBI) solution.
Sjøhest – Norwegian for seahorse – improves offshore wind turbine blade installation efficiency, said GustoMSC and NOV; it connects to the tower, creating an aligned movement for the safe and efficient installation, much like the seahorse’s grasping tail that enables it to resist ocean currents.
The solution consists of a dedicated newbuild NG-5500XL, or a smaller converted jack-up vessel, equipped with a smaller handling crane that picks up the blades from the rack and feeds the trolley. This is combined with the telescopic leader boom that connects Sjøhest with the tower.
Once connected to the trolley, the blade is horizontally transported up along the leader, rotated into a vertical position, and connected to the rotor.
“Large installation jack-up vessels have relatively high day rates; therefore, increased installation time or downtime is costly and needs to be avoided as much as possible,” said the companies. “Sjøhest offers an alternative installation methodology whereby the larger installation jack-up vessels equipped with heavy lift cranes install the towers and nacelles, while the dedicated Sjøhest WBI jack-up vessel with integrated equipment installs the blades. The installation methodology with Sjøhest ensures major time savings as all three blades per turbine can be installed in one day.”
In addition, the installation methodology with Sjøhest enables splitting tower/nacelle and blade mobilisation into separate onshore hubs.