Stena’s first E-Flexer ferry ‘Stena Estrid’ has been fitted with MaK 12 M 43 C and twin-screw Cat marine propulsion drive trains with MPP 1410f propellers, shafts and packaged gearboxes.
She is the first of Stena RoRo’s nine ropax vessels, which include five for Stena Line and several additional vessels that will be on long-term charter for other leading ferry operators, including Brittany Ferries.
Built at the China Merchants Jinling Shipbuilding Weihai Shipyard in China, ‘Stena Estrid’ is 215 m long with 3,100 lane-m of capacity.
‘Stena Estrid’ undertook rigorous sea trials to test the performance of the vessel, including all the on board systems, such as the propulsion plants. She made significant speed on two shaft lines, as well as on one shaft line and another in feathering mode. Per Wimby of Stena Teknik commented “We did 18,5 knots using only one engine, which exceeded our expectations.”
Caterpillar Marine worked closely with Stena’s newbuilding team to supply the main engines and propulsion packages for ‘Stena Estrid’ and so far, six of her sisters in this new series.
Together with Deltamarin, Stena and the yard in Weihai, the companies created a very efficient total propulsion solution as it was determined that the MaK 12 M 43 C and feathering Cat Propulsion MPP 1410f propellers would be the perfect match for this vessel. This package was then further optimised in collaborative extensive simulations and model test work in order to push the ropax performance as high as possible.
Wimby said: “After a long period of optimisation and testing with CMH/Deltamarin, MARIN and Caterpillar, we now see the final product which is the most efficient ship in Stena’s history.”
Janne Uotila, Deltamarin managing director, added:“One of the key principles of Deltamarin designs has always been energy efficiency. Nowadays, due to environmental reasons and stricter regulations even more so and this project is a good example of this. It is a result of close co-operation with Stena and Caterpillar in early stage of the development.”
Mattias Hansson, Caterpillar Marine solutions manager, said; “The open professional collaboration between all parties, from day one throughout the process, has been key to success.”
With a maximum output range of 12,600 kW, the MaK 12 M 43 C engine provides reliable power and performance, Caterpillar said. Developed to meet the requirements of the cruise and ferry markets, this new engine series is the breakthrough into a new class of power.
Coupled with the patented feathering Caterpillar controllable pitch propellers and the ability to optimise the whole package under one supplier, it creates a very efficient solution for this vessel type. Compared to other similar ferries, this vessel is very fuel-efficient and was according to Maritime Research Institute Netherlands (MARIN) the best model ever tested in its class.
When commenting on the design of the new ro-pax vessel, Per Westling, Managing Director of Stena RoRo, stated, “The MaK engines we have are extremely fuel-efficient and require little maintenance.”