Amphibious vessel first look - 'CRC Walrus'


RWE, in partnership with Commercial Rib Charters (CRC), shares a first look at the amphibious vessel ‘CRC Walrus’ which has been designed by Chartwell Marine and built in the Isle of Wight to reach offshore wind farms in shallow waters.

The crew transfer vessel (CTV) was specifically commissioned to access turbines at Scroby Sands, which have become stranded by the natural rising tide of the sandbank on which it is built. The vessel, which can also drive on land, provides access to generation assets affected by dynamic seabed conditions.

CRC Walrus took its maiden voyage in early January and results are positive, achieving speeds of 24 knots on water and 6 kmh on land. The 12-meter vessel has a 1000 kg 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 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.

CRC Walrus has now been working on site successfully for the last four weeks providing a safe method of access to turbines that have been out of reach for considerable time. Trials continue in order to thoroughly optimise the operation and performance of the vessel. It will be operated for RWE by CRC, via a six-year contract.

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

Stuart Hedges of CRC says: "We are thrilled to have had the opportunity to build this vessel for RWE, specialising in shallow water operations has always been our niche so building a conventional CTV with amphibious capabilities has been very exciting. We are very pleased with trials that have been 100% successful".

Phillip Croston-Clegg, General Manager at
Scroby Sands adds: "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".

RWE’s 60 MW Scroby Sands Offshore Wind Farm was one of the first of a group of projects to be built in the UK, and all 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.

For everything you need to know about the strategies used to support the construction and O&M of offshore wind farms, current and future, including supply and demand for service and accommodation vessels, and helicopters -  click here.