Ulstein SX250 – a unique vessel for power plant maintenance

Norwegian shipbuilder Ulstein Group has announced the SX250 vessel project, which is designed specifically for servicing offshore wind farms.


The use of the new vessel will potentially reduce capital and operating costs by up to 50% compared to traditional service vessels (SOVs), while all key functions will remain the same.

The Ulstein SX250 occupies an intermediate position between the large SOVs and the small CTVs. The newcomer can operate in conjunction with full-size equipment, performing auxiliary tasks and maintaining the smooth operation of wind turbines.


The vessel is designed specifically for work at power plants located in areas with moderate waves and shallow waters. In addition to standard tasks, the SX250 can be used for seasonal maintenance, which is usually carried out in the summer.

The design basis of the new project is a patented Ulstein solution, namely TWIN X-Stern. Its main advantage is improved seaworthiness and reduced energy consumption.

The length of the vessel is 47 meters, the width is 13 meters. The number of crew and technical personnel on board can vary from 32 to 40 people depending on the tasks performed.

The maximum speed is 10 knots (18,5 km/h). The vessel is capable of safely operating in waves up to 2 meters high.

Several solutions are available for moving people and cargo between the ship and objects at sea, including Palfinger baskets, OPTS delivery systems and traditional gangways.

An important aspect of the project was its environmental efficiency. The Ulstein SX250 was designed in such a way that as little material and electrical energy as possible would be used during the construction stage.


A new project from Ulstein Group opens up opportunities to optimise the maintenance of offshore wind farms, reducing costs and increasing efficiency.

As a result, the SX250 is expected to be in high demand among offshore wind farm operators with power plants located in open waters.