Following feasibility and concept studies in 2023, Penta-Ocean Construction selected Ulstein for the project. Ulstein proposed the HX118 with the U-STERN™, a design that builds on Ulstein’s successful track record of crane vessels. The chosen design offers a well-balanced combination of a flush work deck, lifting capacity, accommodation and DP capability and will be the largest X-BOW® vessel to date.

The U-STERN™, developed by Ulstein, features longitudinal storage and upending of monopiles along the ship’s centreline. This innovation enables the installation of longer monopiles without overhanging the ship’s sides and allows the vessel to face the waves during the installation, minimising ship motions and fuel consumption.

Since last summer, Ulstein has been collaborating with Penta-Ocean Construction on the Basic Design of the heavy lift vessel, including an extensive model test program. The design is being developed at Ulstein’s Rotterdam office, with significant support from Ulstein Poland during the Basic Design phase.

“We are honoured that Penta-Ocean Construction chose us to design their new heavy lift vessel. This project represents a powerful collaboration between Penta-Ocean Construction, Ulstein and Huisman to design this most capable monopile installation vessel,” says Ko Stroo, lead designer at Ulstein Design & Solutions B.V. “As the project moves forward with its construction at the Seatrium shipyard, Singapore, we remain committed to supporting the parties throughout the construction phase.”