To be able to also offer offshore wind farm maintenance, DEME is investing in its first Service Operation Vessel (SOV). Designed in cooperation with Vuyk Engineering Rotterdam and Marin, the world’s first twin-hulled SOV enables safe crew transfers in rough sea conditions.

The keel laying ceremony took place on December 13 at the CEMRE shipyard in Yalova, Turkey.

Twin Hull Design

The SOV will feature a Small Waterplane Area Twin Hull (SWATH) design, which ensures low wave impact on movements when approaching the wind turbines, compared to a monohull SOV. The vessel will enable safe crew transfers in significant wave heights of up to 2.5 metres, being the first DP2, twin-hulled SOV in the world.

At sixty metres long, the SOV will be equipped with a motion compensated gangway and daughter craft to safely transfer technicians to the wind turbines, increasing the workability and logistics capabilities of the vessel. It is also designed according to the latest comfort standards and can accommodate up to 24 technicians and a nautical crew.

Reduced Fuel Consumption

Environmental considerations are an important element of the vessel design with, amongst others, a waste heat recovery system and a Clean Design notation. With the provided DP2 technology, the vessel can hold its position in rough sea conditions, but still operate with lower fuel consumption when compared to traditional SOVs. According to the Belgian offshore contractor, the vessel can reduce fuel consumption by up to fifty per cent compared to a monohull SOV.

‘We believe the twin-hulled design, a motion compensated gangway and dynamic positioning is a winning combination and will further reduce the costs of wind farm maintenance, especially compared to large monohulls reaching similar workability,’ says Michael Glavind, Business Unit Director DEME Offshore. ‘With this first SOV joining our fleet, we further strengthen our capabilities to offer the full offshore wind package, from installation to maintenance.’

Long-term Charter

Due for delivery in 2021, the SOV will be chartered by Siemens Gamesa Renewable Energy as part of a long-term maintenance contract for the Rentel and Mermaid & Seastar (referred to as SeaMade) offshore wind farms in Belgium. This is the first SOV to serve three different wind farm sites.