VESSEL REVIEW | Raften – Compact hybrid workboat to support Nordlaks' fish farming operations
Norwegian offshore salmon harvesting company Nordlaks has taken delivery of a new hybrid fish farm workboat designed by local naval architecture firm NSK Ship Design.
The all-steel Raften has a length of 28.5 metres (93.5 feet), a beam of 13.2 metres (43.3 feet), a gross tonnage of 500, and a crew of 12 who will operate 24/7 in three-week shifts.
The vessel's duties will include towing, remotely operated vehicle (ROV) support, anchor handling, inspection, and underwater positioning.
Flexible propulsion arrangement
The vessel’s hybrid diesel-electric propulsion system consists of three DI16 90M 640kW (860hp) engines, controllable-pitch propellers, a Stamford S6L1M-C42 750kVA generator, a Corvus Energy 1,100kWh battery pack, and two Brunvoll side thrusters fitted in the bow and the stern.
The battery supports peak shaving in addition to helping reduce fuel consumption in hybrid and full electric modes and ensuring silent operation in full electric mode.
The vessel can also plug into the local grid when berthed, guaranteeing continuous electrical supply for the hotel load without having to rely on the onboard generator.
Wheelhouse and deck laid out for continuous heavy-duty operations
The wheelhouse offers unobstructed 360-degree visibility to provide the crew with enhanced situational awareness when operating near fish pens or when directly supervising activities on the open aft deck.
The wheelhouse also features an ROV workstation through which operators can monitor and control the ROV whenever it is deployed in the water. The ROV on Raften was supplied by Sperre.
The deck equipment includes winches, shark jaws, plate locks, rope pins, and two SHM Solutions remotely controlled boom cranes for net handling. The cranes each have a reach of 25 metres (82 feet) and a lifting capacity of 200 tonnes in addition to being capable of safe and precise manoeuvring for greater safety.
The vessel's accommodation spaces include crew cabins, a mess, a galley with hot and cold food preparation facilities, a lounge, and a gym. Work on the interiors was provided by Maritime Montering.
