ULSTEIN SX221 SOV design for James Fisher.

James Fisher goes for TWIN X-STERN SOV concept

James Fisher unveils the pioneering 'Diamond SOV', an ULSTEIN SX221 TWIN X-STERN® Service Operation Vessel (SOV) concept. Designed by Ulstein Design & Solutions AS, the concept is expected to support the UK’s target of 50GW of offshore wind energy by 2030.

21 June 2022

The Diamond SOV concept is the result of an extensive collaboration of the Diamond Consortium, formed together with the marine industry leaders James Fisher and Sons plc, Ulstein, DNV and Graig.

The result is expected to provide a future-proof design to address the increased demand for SOVs, reduce the levelized cost of energy, and deliver high levels of operability, personnel comfort and sustainability. The concept is aimed at transforming the UK's offshore wind supply chain and supporting the UK's Net Zero Strategy.

Ulstein's TWIN X-STERN® design can be described as having two sterns and four main propeller units. This improves the operational window and makes the vessel ideal for wind farm operations. In addition, the resulting reduced noise and higher comfort onboard are of high value for the crew and technicians onboard. By having excellent performance in either direction, this functionality contributes to an increased number of transfers of technicians per day as well as saving fuel cost per transfer.

"We chose to go with ULSTEIN due to their history of successful innovative designs. We believe the TWIN X-STERN to be the best choice for service operations of offshore wind farms. The philosophy behind the concept has been successfully applied to other vessel segments for many years: developing a specification that meets a market need while allowing for a high degree of customisation and configuration for individual owners and developers."

Jim Hey
group business development director, James Fisher

Economies of scale

"Building SOVs in series volumes achieves significant economies of scale and delivers a design that can be built in multiple yards simultaneously. Considering the anticipated market demand for SOVs in the UK and beyond by the end of the decade, this exciting new concept places the UK at the centre of enabling global offshore wind ambitions," Hey explains.

James Fisher cooperation, ULSTEIN SX221 Service Operation Vessels with the TWIN X-STERN.

Placing sustainability at the fore, the concept will address the supply chain chasm threatening to stymie offshore wind progress with a scalable, modular solution that can be achieved through high-volume series construction to meet developer time and budgetary constraints, the consortium said.

With a significantly reduced energy consumption and increased manoeuvrability, the vessel will also help developers lower scope 3 emissions in the construction of offshore wind farms.

Meeting the environmental goals

"We have successfully partnered over many years with DNV on the Graig-led Diamond business model and we are now applying this proven, scalable strategy to the global offshore wind markets with a particular focus on UK waters, helping to meet the challenging environmental goals in front of us," Hugh Williams, CEO, Graig Shipping PLC, said.

Aims for delivery 2024

The Diamond Consortium is currently in discussion with major shipyard groups to reach specifications in conjunction with valued customers, with the first vessel capable of being completed by the end of 2024.

Further, harsher, longer

"With larger turbines being installed further out at sea, vessels and crews will be travelling greater distances and working for longer periods of time in harsher environments," Arnstein Eknes, segment director, Special Ships, DNV, said.

"The opportunities offered by digitalisation and introduction of sustainable solutions, whilst maintaining high dependability during operations are vital for the next generation of SOVs. This is why we are thrilled to be spearheading development of smart notations and services facilitating the novel solutions provided by this next-generation ULSTEIN SX221 Diamond SOV."

Latest technology in offshore wind

Lars Ståle Skoge, commercial director at Ulstein Design & Solutions AS comments:

"We are very happy that our design has been chosen for this project. We are pleased to contribute with our latest technology to the growing offshore wind market. Being able to deliver on emission goals and operability is becoming a larger criterion when contracts for wind farm operations are tendered."

The award-winning hull designs by Ulstein Design & Solutions have numerous times proven to be a competitive edge for the ship owners. The ULSTEIN TWIN X-STERN® concept dramatically improves the manoeuvrability, movement and ability to stay in position for the vessel. Qualities that make the TWIN X-STERN ideal for wind farm operations. Further, the concept allows for reduced noise, more comfort onboard and the potential to save significant amounts of energy in operation.

Get in touch

Lars Ståle Skoge DSC4468 comp bw

Lars Ståle Skoge

Commercial Director
Ulstein Design & Solutions AS

Latest news

Ulstein Verft DJI 0125
Press Release

Ulstein Group result 2023

In 2023, Ulstein Group recorded revenues of NOK 1.4 billion and an operating profit of NOK 49 million. The knowledge and experience Ulstein have gained through more than a hundred-year history have created a dynamic and flexible organisation that we now benefit from in the transition to a greener and gradually more fossil-free future.

Lars Ståle Skoge DSC4468 comp bw

Lars Ståle Skoge

Commercial Director

Ulstein Design & Solutions AS