RWE unveils amphibious offshore turbine maintenance vessel

Designed and operated by UK firm Commercial Rib Charter Ltd – which operates Europe’s largest fleet of RIB vessels – the ‘CRC Walrus’ was specifically commissioned to access turbines at RWE’s 60 MW Scroby Sands wind farm off the coast of Norfolk. The project is one of a number of wind farm to be built in coastal locations with relatively shallow waters close to shore. Scroby Sands was built on a prehistoric sandbank and, because of natural changes in the marine environment and coastal erosion, this has risen over time effectively isolating four turbines from being accessed by service vessels.

The vessel, which can also drive on land, provides access to generation assets affected by dynamic seabed conditions. Its innovative design means that the two wheels at the front and one at the back can be deployed, similar to an aircraft, when transferring from deeper water into shallow water and sand.

From first concepts less than 18 months ago, the project has been developed, designed and built with collaboration between RWE and Commercial Rib Charter (CRC). Naval architect Chartwell Marine carried out design specifications and the vessel was constructed by Diverse Marine in their Isle of Wight boat yard.

According to a statement from RWE, CRC Walrus took its maiden voyage in early January, achieving speeds of 24 knots on water and 6kmh on land. The 12-meter vessel has a 1000kg cargo capacity and is capable of safely transferring 10 technicians and two crew to any of the turbines within the Scroby Sands array, including on the raised sandbank.

The vessel has now been working on site successfully since early February and trials continue in order to thoroughly optimise the operation and performance of the vessel.

Phillip Croston-Clegg, General Manager at Scroby Sands said:” This new vessel is a successful innovation and testament to the fantastic collaboration between Commercial Rib Charter and the RWE team. Working with experienced vessel operators to design a unique solution to a problem that was impacting our maintenance, has been invaluable. In addition, this could pave the way for broader applications in similar areas.”