New renewable services vessel packs versatility and capability into a small platform
Scottish vessel owner Seafast Marine took delivery in October of Isle of Jura, a 33-m renewable services vessel (RSV) that can handle a range of duties in the offshore renewable energy sector in shallow and deep water.
Isle of Jura represents an evolution of Dutch shipbuilder Damen’s Multi Cat, a line of multi-purpose workboats designed in various configurations up to 30 m, with standardised components, deck cranes, towing pins and winches for towing and anchor-handling duties. The idea behind the Multi Cat is to pack as much versatility and capability into a small footprint as is possible, while minimising the production time and shipbuilding cost. Over 300 Multi Cat designs have been delivered over the last 25 years.
Pushing this ‘jack-of-all-trades’ design further, two years ago Damen delivered the first Multi Cat vessel specifically for supporting the offshore renewables sector.
Working in co-operation with another Scottish vessel owner, Delta Marine, which has four Multi Cats in its fleet, Damen delivered its first RSV 3315, Voe Vanguard, in May 2017.
One of the largest of Multi Cat designs, Voe Vanguard has an overall length of 33 m, beam of 14.5 m, draught of 2.6, with two deck cranes with capacities of 15 and 9 tonnes. Delta Marine and Damen adapted the traditional Multi Cat design for the offshore renewables market by moving the wheelhouse forward and leaving the aft deck open, providing 300 m2 of unobstructed deck space.
While it is capable of performing all duties normally expected of a Multi Cat, Voe Vanguard’s DP class 2 capability, four-point mooring system and bollard pull of 42 tonnes also make it particularly well equipped to tackle offshore wind and tidal energy projects, which are normally sited in areas subjected to strong currents.
Outfitted with a Kongsberg K-Pos DP-21 DP system, the RSV has a large stern thruster and four azimuth thrusters, with the capability of switching between DP2 and DP1.
Both Isle of Jura and Voe Vanguard were built by Damen Shipyards Hardinxveld, which constructs a range of tugs, workboats and utility vessels for harbour and terminal operations.
Much like Voe Vanguard, Seafast Marine’s Isle of Jura has four azimuth thrusters, DP2 capability and a four-point mooring system, two large cranes, hydraulic shark jaws and an AHT winch.
Damen sales manager UK Arjen van Elk says: “Isle of Jura is like a Swiss army knife: so multi-functional for such a small vessel.”
The RSV’s versatility allows it to be used for a range of duties, such as anchor handling, dredging, towing or walk-to-work functions. The wheelhouse provides 360-degree visibility and sky windows, for the best possible vantage point. Internally, the vessel’s galley is fully equipped, and there are six double crew cabins and three single crew cabins, providing berths for up to 15 crew.
“The RSV line of vessels is multifunctional and will always be developed or re-developed according to the varying wishes of different end users,” a Damen spokesperson told Offshore Support Journal. Damen points out that the multifunctional design of the vessel provides flexibility to the layout of its deck, making it suitable for use in different market segments. This has prompted interest in the vessel from owners in the renewables and offshore oil and gas segments, says Damen.