Being a pioneer is both risky and rewarding. When Royal Caribbean Cruises became the first customer for the new Wärtsilä 46TS-DF engine, they knew the rewards it could bring. But during the collaboration with Wärtsilä on its introduction, what was needed to make sure they could realise the engine’s full potential?
Cruise passengers expect nothing but the best when they book a vacation with one of Royal Caribbean Group’s (RCG) cruise lines. That’s why the company chose the new Wärtsilä 46TS-DF engine for its new Oasis-class vessel. The engine helps to ensure maximum comfort for passengers, with low noise and vibration, while fulfilling RCG’s need for excellent fuel efficiency and low emissions.
The Oasis class vessels are among the largest cruise ships sailing today. The latest in this prestigious line of vessels, Utopia of the Seas, entered service in July 2024. The company has installed many Wärtsilä engines over the years, but this first-of-series engine demanded a more extensive collaboration project.
“It is very important to introduce new technology on our ships in order to continue advancing our net zero ambitions while providing an exceptional experience for our guests,” explains Laurent Tessier, Technical Director for Royal Caribbean Group.
With built-in upgradability and fuel flexibility, the Wärtsilä 46TS-DF is helping to power a more sustainable future for shipping. It represents the next generation of medium-speed engines, setting a benchmark for fuel efficiency and emissions performance, and is ready to run on alternative fuels.
The engine helps to ensure maximum comfort for passengers, with low noise and vibration, while fulfilling RCG’s need for excellent fuel efficiency and low emissions.“
Tessier says that introducing a new engine is always challenging, but Royal Caribbean Group was up for the challenge to help them meet their decarbonisation targets. The journey took around three years, starting with the decision to use the engine, collaborating on its development and introduction, signing the contract and successful factory acceptance tests. Getting to this point took lots of close teamwork between Royal Caribbean Group, Wärtsilä, and French yard Chantiers de l’Atlantique.
Tessier believes that the close collaboration benefitted all three parties. For Royal Caribbean Group it helped them learn all about the new engine’s functionalities and technologies. For the yard, it helped with integration work. Wärtsilä got valuable experience and insight that led to improvements on the original design.
Glenn Mattas, Sales Director at Wärtsilä, notes the importance of the new technology qualification process, which was run together with Royal Caribbean Group, Chantiers de l’Atlantique and DNV. “We got some good feedback, and a few things led to some modifications in our design. The customer’s direct feedback on the design of the engine will serve us for the future as well.”
Royal Caribbean Group chose the Wärtsilä 46TS-DF for its power density and reduced fuel oil consumption – which is much lower than the previous version of the engine. Efficient engines are essential in helping the company reach its sustainability targets. The engine was also chosen for its ability to meet guest demands – primarily minimal vibration, emissions and noise. It’s no surprise, then, that these were a focus of the factory acceptance tests carried out in Vaasa, Finland in November 2022.
“The first thing to check was the performance,” shares Tessier. “For us, specific fuel oil and gas consumption is very important. We also checked the vibration, the normal behaviour of the engines, different loading points, transient operations and safety,” he continues. “We knew this was a first-of-series engine, but I was impressed by the quality, behaviour and performance during the tests.”
Reflecting on the collaboration, Tessier, Mattas and Dominique L’Hostis – Project Manager of the Machinery Department for Oasis of the Seas at Chantiers de L’Atlantique – agree that the key to success was open, transparent communication.
Efficient engines are essential in helping the company reach its sustainability targets. The Wärtsilä 46TS-DF was also chosen for its ability to meet guest demands – primarily minimal vibration, emissions and noise.“
“It took a bit of time to learn about each other’s skills, competencies and experience,” says Tessier. “But with good spirit and transparency and close communications channels Royal Caribbean Group has much better knowledge of the engine and the technology,” he adds. “Thanks to the transparency and open-minded orientation you get closer to the solution to fix any issues faster and better.”
Mattas agrees: “From Wärtsilä’s side, especially R&D, in the beginning it was a challenge to open up and discuss the details with the customer. It’s not something that we do every day. But after a while, things opened up and we had very good dialogue.”
“The best way is always to have clear communication and transparency. If we had a problem, we tackled it together and put it behind us,” says L’Hostis. “A lack of transparency from the supplier would mean that something is being hidden.
The collaboration was seen as a big success by all parties and set a great benchmark for future projects as Royal Caribbean Group continues on its journey to more sustainable cruising. “Wärtsilä is a good partner to help us achieve our long-term target of net zero emissions and our mid-term target of delivering net zero cruise ships by 2035,” concludes Tessier.
Last updated: May 2026
Content owner: Wärtsilä Marine
