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UPDATED: GC Rieber Shipping charts course for service operation vessel market
Norwegian offshore support vessel owner GC Rieber Shipping is entering the offshore wind market for the first time with two purpose-designed service operation vessels (SOVs)
GC Rieber Shipping chief executive Einar Ytredal said, “In 2020, we made a decision to become a pure shipowner and project-house with a focus on developing profitable and sustainable maritime projects.
“We are proud to launch WindKeeper, our first project. The solid environmental and operational performance of the WindKeeper testifies to the strong technical capability within GC Rieber Shipping. Our ambition is to build WindKeeper into a substantial and valuable player in the offshore wind industry.”
GC Rieber Shipping chief commercial officer Christoffer Knudsen said, “We look forward to demonstrating to clients the exceptional performance of the WindKeeper design. WindKeeper will drive down charterers’ daily costs and substantially reduce their emissions, improving their environmental footprint.”
The company has been developing the design of the SOVs for some time, working closely with naval architect LMG Marin. “The WindKeeper SOV was developed to deliver four key attributes to the offshore wind market,” said GC Rieber. “These are: a customized vessel developed from ‘scope of work’ point of view; a vessel with lower operating costs compared to conventional designs; exceptional operability; and a significant reduction in greenhouse gas emissions and environmental footprint. The four requirements have led us through an innovation journey culminating in the high-performance SWATH hull.”
The result is the ‘WindKeeper’ design, which departs from convention having a small water area twin hull (SWATH) rather than a monohull, an especially stable design with excellent seakeeping that will also provide enhanced operability. The design is also characterised by what the owner designed as “ultra-low fuel consumption and the option of fully electric operation in the field.”
The SWATH hullform has been applied in a number of other applications – and selected by another SOV owner, DEME Offshore – and is a proven method for reducing vessel motions. The design has been model-tested at MARIN in The Netherlands and SINTEF in Norway and its reduced motions enhance crew comfort and reduced the incidence of seasickness.
Mr Knudsen told OWJ, “We have worked intermittently in the offshore wind market before but came to realise that it was going to be a huge market and that we needed to do something. Our start point was how best to service windfarm and meet the needs of windfarm technicians.
“We quickly came to realise that a monohull hullform of the type used to transport cargo for oil and gas isn’t the best solution. For the SOV market, you need to be able to transport 150 tonnes of cargo, keep windfarm technicians in good shape and safely connect to a turbine in in challenging conditions. You need a vessel that moves far less than a monohull, hence the SWATH.
“Typically, a monohull will give you availability 60-80% of the time, depending on conditions, but with a SWATH you get 95% availability in North Sea conditions. That’s a lot more days when you can service a windfarm. With a SWATH the motion sickness index (MSI) is also much lower. With the WindKeeper it is less than 5% in a significant wave height of 3m Hs. That’s less than the MSI required for a cruise ship.”
The vessels will have 40 single cabins for offshore wind technicians, all with daylight and will be fitted with a 30-m motion-compensated gangway system capable of operation in a significant wave height of 4.0 m Hs. The vessels will also be fitted for cargo transfer with trolley operations and will have a 2 tonne 3-D lifting capability. The WindKeeper SOVs will also provide stepless boat landing operations. With a length overall of 57 m, breadth moulded of 22.5 m and design draft of 6 m. The WindKeeper SOVs will also have a 300 m2 warehouse and 350 m2 of deck space.
Another highly innovative feature of the WindKeeper is the battery hybrid propulsion system, with the option for 100% battery operation. As Mr Knudsen explained, because the SWATH SOV is smaller than a monohull with the same cargo and passenger capacity, it requires less power. This means that it can use smaller, less expensive engines than a monohull SOV.
GC Rieber’s SOVs will make use of six high-speed engines rather than the large medium-speed engines a monohull typically would use. Typically, these would Volvo Penta, Caterpillar or Scania engines. Six smaller engines confers a high level of redundancy on the propulsion system, but in due course, Mr Knudsen explained, the ships could be supplied with a much larger battery pack and only two diesel engines for back-up. “The technology is there now,” said Mr Knudsen.
“We can install 13-19 MW of battery power and operate on batteries alone when charging infrastructure is available. If a WindKeeper SOV was awarded a charter on a windfarm with a charging station on a substation, we could deliver a battery-powered vessel with fewer engines by 2025. We could operate on batteries 18-20 hours a day, in zero-emissions mode.”
The company has placed firm contracts for two WindKeepers SOVs at Cemre shipyard in Turkey. The order includes options for two more vessels. The first vessel will be delivered in Q1 2025.
A stand-alone company, WindKeeper AS, wholly-owned by GC Rieber Shipping, has been set up to own and operates the SOVs, which will see the company invest approximately €110M.
The vessels are fully financed through a combination of equity and debt financing. Sparebanken Vest and Eksfin provided long-term loan facilities of minimum €51M.
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