Port and installation constraints of Tension Leg Platforms (TLP) floating wind turbines

Abstract

Floating offshore wind needs to go from pre commercial phase to full commercial use if it’s full benefits are to be realised. The port and installation requirements for barge, semi submersible and Spar substructure types are understood, though more research is needed to reduce cost. Floating Wind Tension Leg Platforms (TLPs) have constraints on tow out intact stability and complications in installing the tension moorings. The paper will review the port and installation requirements of TLPs as floating wind substructures. The TLP has the advantages over other substructure types for low in place motions and minimum area taken up on the seabed. There is experience from the offshore oil and gas industry of TLPs which can assist in developing cost effective TLP designs for floating wind. The priorities are the turbine fit out port and the vessels required for TLP offshore installation. Cost reduction during the port and installation phases are based on the best techniques from the offshore oil and gas industry, from bottom fixed wind turbines and the installation of other floating wind types. Installation methods considered are: variable draft between tow out and operations, piece small installation offshore and fitting temporary buoyancy for the tow out phase. Design for installation includes expanding the weather window in which the TLP floating substructure can be transported to site and configurations to facilitate mooring. The simplification of installation methodology will reduce time spent offshore and will minimise risks to personnel.