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Friday, August 13, 2021 

Offshore vessel operator HST Marine has taken delivery of 'HST Ella', a new hybrid crew transfer vessel (CTV) designed by naval architect Chartwell Marine, the first Chartwell 24 vessel with hybrid power, following completion at local Isle of Wight shipyard Diverse Marine.

HST CEO Tom Nevin said: “Modern crew transfer operations in offshore energy increasingly require proven vessels with a powerful presence on the water. At the same time, a future-proof fleet consists of vessels with strong green credentials as the goal of emissions reduction continues to move up the agenda. Rapidly maturing hybrid technology means that environmental consciousness can sit hand in hand with operational excellence, and in the HST Ella, we have a vessel that delivers both, following a consultative design process with Chartwell Marine, and a high-quality build at Diverse Marine.”

HST Ella demonstrated transit speeds of 10 knots on electric propulsion and 30 knots on diesel, while during port operations, the vessel’s electric operation mode allows for quiet and zero emission low speed manoeuvrability. This is enabled by the vessel’s hybrid propulsion system. An electric motor sits alongside a diesel engine to drive a high-performance CP propeller. The vessel’s advanced hull form provides reduced frictional resistance, and the use of Hydrotreated Vegetable Oil (HVO30) as fuel is considered a first for a new build CTV.

Advanced CTVs such as the HST Ella are increasingly expected to perform a range of auxiliary duties alongside personnel transport. The 26m vessel is able to carry 24 industrial personnel alongside a maximum payload of 15t, ensuring maximum versatility when supporting offshore wind operations. HST Ella will be deployed at the East Anglia 1 (EA1) wind farm.

Ben Colman, Director, Diverse Marine, said: “The UK is rightly proud of its world leading maritime industry, and with this market first hybrid CTV, designed and built on the South Coast, we are proud to add to a long record of maritime innovation in this country. As we hand over the keys to the HST team, we wish them all the best as they take the HST Ella to charter to support safe, efficient wind farm operations.”

Andy Page, MD Chartwell Marine said: “Whether designing a diesel-powered CTV with an innovative hydrofoil system propelled by waterjets, or, as in this case, a large hybrid-electric CTV using HVO fuel with a changeable pitch propeller, we always look to ensure that the proven characteristics of the Chartwell 24 platform are built in. Designing for hybrid operations brings specific challenges, but our central philosophy is that we design with the vessel’s eventual operational profile front and centre, and we have been proud to work with Diverse Marine and HST to incorporate lessons learnt from best practice CTV operation into this vessel.”

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