Norwegian shipowner to build green ships for a green industry

Østensjø Rederi, a company with a long history of innovation and a long-term focus on environmentally friendly shipping, has signed a letter of intent to construct four unique service operation vessels that will be refitted with fuel cells to enable them to operate as ‘zero-emissions’ vessels.

As highlighted previously by OWJ, interest is growing rapidly in environmentally friendly technology for offshore wind vessels of all types. CWind in the UK recently secured a long-term charter contract with developer Ørsted for a crew transfer vessel with hybrid diesel/electric propulsion, and hybrid propulsion with batteries has been proposed for installation vessels.

The ‘commissioning service operation vessels’ as the Norwegian company designates them are designed for use during the commissioning and operation of offshore windfarms. They will thus be somewhat larger and have significantly more accommodation for windfarm technicians than Østensjø Rederi’s existing SOVs, Edda Mistral and Edda Passat, which support operations and maintenance alone.

Østensjø Rederi investment director Håvard Framnes tells OWJ that, in addition to being larger vessels than Mistral and Passat, they will be designed and fitted in such a way that, in addition to being less expensive to operate, their emissions of greenhouse gases will be around 30% lower than existing designs.

The 88.3-m vessels will be delivered from early 2022 onwards and will serve as offshore bases for wind turbine technicians. They will accommodate up to 97 technicians and 23 marine crew and will be fitted with anti-heeling and roll reduction systems to provide a particularly stable working platform. The motion-compensated gangway system with which they are fitted will have an adjustable pedestal to ensure safe, efficient access to turbines.

Østensjø Rederi chief executive Kenneth Walland says, “We are very excited about this newbuilding programme. Significant growth is expected in the offshore wind market over the next decade. In addition to our existing vessels, both on long-term contracts with Ørsted, the newbuildings will strengthen our market position in offshore wind.”

The vessels will have a hybrid propulsion system with batteries and the generators on board will be IMO Tier 3 certified. Together with partners, Østensjø Rederi is working on new technology based on hydrogen. The newbuildings will be prepared for this technology to be installed, which, the company says, “will turn the CSOVs into zero-emissions vessels without compromising operational capability. “For Østensjø Rederi it is important to continuously push the development of environmentally friendly technology. We firmly believe our new CSOVs will be the first zero-emissions vessels in this market,” says Mr Walland.

Mr Framnes tells OWJ that the vessels, which are being designed by Salt Ship Design in Norway in close co-operation with Østensjø Rederi, will use fuel cells powered by hydrogen to achieve zero-emissions status. He says they were being designed so that fuel cells and tanks for hydrogen could be installed later. Infrastructure for bunkering ships with hydrogen is not yet widely available, but Mr Framnes and his colleagues expect it to be developed as more and more shipowners of all types invest in hydrogen and in fuel cell-powered units. Hydrogen can also be used in dual-fuel engines but Østensjø Rederi has opted for fuel cells to enable it to go straight to zero-emissions, rather than just achieve a partial reduction in emissions.

The ships will be built at Astilleros Gondán in Spain, a decision founded on a strong relationship following the construction of 13 vessels already delivered to Østensjø Rederi by the yard. Mr Framnes says the company expects to sign a contract for the ships by the end of 2019.