Japan’s Penta-Ocean Construction has entered into a shipbuilding contract with Seatrium for the construction of what will be the world’s largest heavy lift vessel (HLV). This state-of-the-art vessel will be used for the installation of offshore wind turbine monopile foundations and will feature a fully revolving 5,000-tonne crane and the innovative Ulstein U-stern.
The U-stern, with its U-shaped notch, is designed to upend a monopile stored lengthwise on the vessel using the 5,000-tonne crane and an upending system with a gripper for direct installation at the notch. This design enables the hull of the HLV to shield its operations from waves and currents, reducing ship motions.
The hull design contract has been awarded to Ulstein Design & Solutions, while Huisman Equipment will build the on-deck equipment, including the crane and upending system, with completion scheduled for May 2028 and operations anticipated in the fall of the same year.
Huisman Equipments’s 5,000-tonne active heave-compensated tub mounted crane has a dual main hoist and universal quick connector for efficient and safe tool changes, a compact tail swing for deck space optimization, and no counterweight, providing full revolving capacity.
In addition to its impressive crane, the HLV will boast several notable features. It will be capable of installing monopiles weighing up to 3,000 tons, will have the capacity to load and transport multiple monopiles, and will be equipped with a ClassNK DPS2 dynamic positioning system featuring nine thrusters with a total output of 25,000 kW or more, ensuring high positioning capability. The vessel will also include a battery storage system and will be methanol-ready.
Ulstein Design & Solutions stated that the award of its contract follows feasibility and concept studies based on its HX118 with the U-stern. The vessel will also feature the X-bow design and, at 215 meters long and 56 meters wide, will be the largest X-bow vessel ever built.
The innovative U-stern design allows for longitudinal storage and upending of monopiles along the ship’s centerline, minimizing ship motions and fuel consumption while enabling the installation of longer monopiles without overhanging the ship’s sides.
