Offshore heavy Transport (OHT) has signed a contract with China Merchants Heavy Industry (CMHI) for the construction of a 48,000 dwt semi-submersible offshore wind farm foundation installation vessel.
The contract has an extension option for up to three additional vessels. The first vessel will be ready for project deployment from early 2021, the company informed.
The design has been developed by OHT in cooperation with Ulstein Design & Solutions, Liebherr and DNV GL.
“We have one overriding goal with this initiative; to bring down the cost of building offshore wind farms. Our existing fleet already represents the most efficient way of transporting offshore wind farm foundations over long distances. Combining this with the patent pending Ulstein Alfa Lift installation vessel design, we expect to set a new benchmark in cost per foundation installed. We look very much forward to working closely with the industry to achieve our ambitious targets,” said Torgeir E. Ramstad, CEO for OHT.
Liebherr will deliver the crane which has been designed to be particularly robust with respect to motions and dynamics, enabling the crane to lift loads up to its maximum capacity in challenging offshore conditions.
The vessel, with a total length of 216.3 m, and a breadth of 56 m., has a usable deck area which exceeds 10,000 m2. Up to 10 x 1,500 t ultra-large jacket foundations or 11 x 2,000 t XXL monopiles together with transition pieces and mission equipment can be loaded on to the deck, transported to the wind farm, and installed – all with the same vessel, the company explained.
To enhance sea state limitations and reduce weather downtime, Alfa Lift has the capability to submerge offshore during the installation operation.
Due to the versatile nature of the design, the vessel may also serve other secondary markets within heavy transportation, installation and decommissioning.