Function
Equipment to move and lift major turbine components for pre-assembly, and for assembly with the floating substructure at the quayside of the construction port.
What it costs
About £13 million for a 450 MW floating offshore wind farm.
Who supplies them
Land-based cranes and moving equipment: Ainscough, Mammoet, Sarens and Weldex.
Jack-up cranes: DEME, Fred Olsen, Jan de Nul, Seajacks, Seaway 7 and Van Oord.
A landside crawler crane lifting a nacelle onto a floating substructure. Image courtesy of Port Pictures / Danny Cornelissen. All rights reserved.
Key facts
Heavy loads are generally moved around port quaysides using SPMTs.
The main options for lifting turbine components onto floating substructures are either land-based ring cranes or using vessel-mounted cranes (on jack-up vessels). The height and reach requirements to lift a nacelle onto the tower of a floating substructure are significant and push mobile cranes to the limits of their lifting capabilities. A minimum crane capacity of 800 t with a hook height of approximately 160 m and reach of 30 m from the quayside is required to lift 15 MW nacelles into place on the reference semi-submersibles.
We expect that most floating offshore wind construction ports will use a wind turbine installation jack-up vessel in port for heavy lifting operations of turbine components. Older jack-up installation vessels or barges may be used providing they have sufficient reach and crane capacity. Additional hook height can sometimes be provided by jack-up legs depending on their length with respect to the depth of the quayside. The sea bed at the quayside should be levelled and have sufficient load bearing capacity for the jack-up legs.
Some ports might invest in landside cranes. Landside cranes can either be semi-permanent ring cranes or crawler cranes.
Specialised lifting equipment is required under the hook to ensure that loads are level when lifted, wind-induced movement is minimised, and final alignment is accurate. For nacelles, blades and towers, this equipment is normally designed and provided by the wind turbine supplier.
What’s in it
- Crawler crane
- Jack-up, or barge-mounted crane
- Ring crane
- Specialised lifting equipment
- SPMTs