The marine engine that is best-in-class for fuel economy, with compact size and impressive power-to-weight ratio

On a recent ferry crossing from Livorno to Olbia in Sardinia, I was interested to discover that our vessel (the MS Cruise Ausonia) is powered by a series of four Wärtsilä 46 12V46C diesel engines. It seems appropriate that this fast, modern vessel, should be powered by one of the most technologically advanced marine engines on the market. The crossing took me across the Tyrrhenian Sea which is ring-fenced by Corsica, Sardinia, Sicily and Italy. As a major trade and tourist route, and with four distinct natural entry/exit points, congestion on the sea can be a problem, thus leading to ecological concerns and restrictions. The 46 complies with all the emission regulations and can easily change fuel with a smooth transition that does not affect engine loads and power output. The same engine also powers many of the other vessels in the Grimaldi fleet.
Clare Hogg, Director of Marketing and HR at Diesel Marine Group

The Cruise Ausonia was built in Flenderwerft, Lübeck, Germany as MS Superfast XII with an overall length of 200m.  She has a Ro/Ro capacity of 2,400 linear metres for 500 cars and 1,800 passengers. On sea trails she achieved an astonishing 31.25 knots with a service speed of 29 knots. She joined the Grimaldi fleet in 2018 and today she operates in a more relaxed mode with an official service speed of 19 knots, although sometimes she may be allowed to breath a bit deeper at 22 – 23 knots.

Although introduced in 1987, the 46 has benefited from over 30 years of continuous improvement adapting to the latest technical advancements and is still best in class. The engine has also been further developed to cater for demand for dual fuel engines in the guise of the Wärtsilä 50DF.