DEME has launched its first ever Service Operation Vessel (SOV) at the CEMRE shipyard in Yalova, Turkey. Named Groene Wind, the Small Waterplane Area Twin Hull (SWATH) vessel will be deployed for wind farm maintenance activities.

Groene Wind is due for delivery in 2021 and will be directly chartered to Siemens Gamesa Renewable Energy for the maintenance of the Rentel and Mermaid & Seastar (known as SeaMade) offshore wind farms in Belgium. This is the first DP2, twin-hulled SOV in the world and the first to serve three different wind farm sites.

The name Groene Wind (green wind) perfectly reflects DEME’s ambitions to remain a leader in the offshore wind industry. Investing in such a pioneering vessel also means that the company can offer the total package of services to the offshore wind industry now – from installation to maintenance.

DEME’s in-house newbuild team worked in close collaboration with Vuyk Engineering Rotterdam and research institute MARIN. The new vessel significantly improves safety, comfort and workability for wind farm technicians – even in the roughest sea conditions.

Reduced fuel consumption

The SWATH design ensures low wave impact on movements when approaching wind turbines, compared to a traditional monohull SOV. Groene Wind will enable safe crew transfers in significant wave heights of up to 2.5 metres. Its DP2 technology means that the vessel can hold its position in rough seas, but at the same time operate with lower fuel consumption when compared to traditional SOVs. An impressive fuel consumption reduction of up to 50 per cent is said to be achieved compared to a monohull SOV, further reducing the cost of wind farm maintenance.

In line with its green credentials, environmental considerations are integral to the vessel design and include a waste heat recovery system and a Clean Design notation.

Safety and comfort

At 60 metres long, the SOV will be equipped with a motion compensated gangway and daughter craft to safely transfer technicians to the wind turbines. It is also designed according to the latest comfort standards.

The technical details are: 3244 GT, 330 DWT – dimensions: L oa x B x D (d) = 61.70 x 23.20 x 13.65 (6.50) metres. Propulsion is provided by 4 MTU main engines, type 12V4000M23S with an output of 4x 1870 hp or 1375 kW at 1800 rpm. Accommodation is provided for 24 technicians and a nautical crew.

Michael Glavind, Business Unit Director DEME Offshore, says the Groene Wind ‘highlights the DEME innovative spirit’ as well as the company’s ‘willingness to invest in green technologies’. He adds: ‘This further boosts our ability to serve the growing offshore wind industry, throughout the entire lifetime of an offshore wind farm. We are delighted to take this important step together with our partner Siemens Gamesa Renewable Energy, which also shares our ambitions for the energy transition.’