The next addition to the Norwegian Coastal Administration’s (NCA) multifunctional vessel fleet, OV Ryvingen, is targeted for delivery in late 2018.
Designed by Fitjar-based Heimli Ship Design and built by Fitjar Mekaniske Verksted, OV Ryvingen’s duties will include oil-spill protection-related operations and shipping-lane maintenance.
The NCA is currently renewing its multifunctional fleet and OV Ryvingen is the fourth vessel in this programme. It measures 46.6 m in length with a 12 m beam, making it longer than its predecessors and capable of carrying larger cranes; but it also improves on them in other ways.
From the outset, the NCA wanted this vessel to be environmentally friendly, with a significant proportion of the criteria for the construction award relating to environmental characteristics. The vessel itself further develops the hybrid propulsion system introduced on sister ship OV Bøkfjord.
The designers and builders worked closely with suppliers and subcontractors to ensure that a low-environmental impact philosophy was applied to the vessel. For example, Fitjar Mekaniske Verksted looked to Rolls-Royce Marine for the vessel’s propulsion system which includes the world’s first commercial permanent magnet azimuth thruster, as well as a SAVe CUBE, a single DC distribution switchboard that houses all of the vessel’s frequency drives.
Where OV Bøkfjord mounted three high-speed engines, Rolls-Royce Marine opted for a single six-cylinder medium-speed Bergen engine running a dual generator system, which improves both fuel efficiency and maintenance.
Norwegian-Canadian Corvus Energy was chosen to provide the vessel’s energy storage system (ESS). The Orca ESS will give the vessel an available capacity of 2,938 kWh – a significant step up from OV Bøkfjord’s 850 kWh capacity. This will allow the vessel to operate on battery power alone for hours at a time, without using the diesel engine. OV Ryvingen is also designed to operate on battery power when docked, with capability for the batteries to be recharged from an onshore power supply where available.
Corvus Energy senior vice president of business development Halvard Hauso sees OV Ryvingen’s ESS capacity as the shape of things to come, saying “The electrification of vessels will see an increasing utilisation of higher battery capacities.”
A benefit of the hybrid system for the vessel’s crew and for nearby marine life is that it cuts down on noise and vibration.
Rolls-Royce Marine general manager of sales John Roger Nesje said: “A complete systems delivery like this enables us to think efficiency and lower emissions throughout the ship’s equipment. For example, the Ryvingen’s main engine will be connected to our electrical system, which means its rotational speed can constantly be varied depending on the load; we save energy here as well.”
Other innovative features include the ability to re-use heat produced by the engine, which is stored and used to warm up the crew quarters while in port.
Rolls-Royce Marine also provided the vessel’s automation, dynamic positioning and control systems.
DNV GL business development leader Kay Erik Stokke, who advised the NCA on the project, said he was impressed at how suppliers had met the environmental requirements, describing the vessel as “a green flagship”.
The NCA’s vessel renewal plan provides scope for up to eight vessels and Fitjar Mekaniske Verksted’s contract for OV Ryvingen contains an option for an additional vessel. The yard is already heavily involved in the scheme, having built two of the three vessels delivered so far - OV Utvær, launched in 2012, and OV Skomvær, launched in 2013. A third vessel, OV Bøkfjord is being built by the Danish shipyard White Sande.