INTERVIEW: Oceanbird’s Niclas Dahl and Wallenius Wilhelmsen’s Roger Strevens speaks with Oceanbird Managing Director Niclas Dahl and Wallenius Wilhemsen’s VP, Global Sustainability, Roger Strevens, about the potential for wing sail technology to slash carbon emissions for both new and existing vessels in a maritime industry searching for decarbonisation solutions.

Oceanbird is looking to lead a renaissance in wind-assisted propulsion. The Alfa Laval-Wallenius joint venture is developing a Ro-Ro sailing vessel, Orcelle Wind, for car carrier Wallenius Wilhelmsen which it says will be able to provide an absolute emissions reduction in the region of 60% when in operation in a transatlantic service. Central to the design of the vessel is the company’s wing sail, each of which, Oceanbird says, can reduce instantaneous emissions by 7-10% in a retrofit scenario.

Next year will see the wing sails installed on an existing Wallenius Wilhelmsen vessel, the 2009-built Tirranna, for full-scale sea trials. This retrofit is expected to provide valuable data that will contribute to the development of the Orcelle Wind ahead of its aimed deployment in 2027. caught up with Oceanbird’s Managing Director, Niclas Dahl and Wallenius Wilhemsen’s VP, Global Sustainability, Roger Strevens to discuss the role wind propulsion technology is likely to play in the shipping’s decarbonisation transition, the potential for Oceanbird’s wing sail technology to be used by other vessel segments, and how much interested parties can expect to pay.

There are several wind propulsion technologies either coming onto the market or in development. Is this range likely to increase or do you expect a single technology to emerge?

Niclas Dahl: For me it’s quite interesting because I started developing ballast water treatment systems 20 years ago and it was exactly the same thing. A new compliance solution need was created  and I think there were 70 different suppliers initially. In the end it went down to two different technologies with maybe 5-10 different suppliers. I think you will see the same thing here. I think [the range of technologies] will spread even more before it gets less and then you will start to see what the impact of it is really when you try it and which is the best. It’s not only regarding performance, but also about how you get service.

Roger Strevens: Our perspective as an owner/operator is different from Niclas’s as a solution provider, but on this one our views are aligned: there will be convergence in the wind-solution market over time. Of course, we have looked at all the different options for wind propulsion that are out there and it was clear to us that Oceanbird’s wing sails are by far the most promising technology for our kind of vessels and how we operate them. We also strongly agree with Niclas’s point about global service. If you’ve got a critical system, you need to know support is going to be there for it if, when and where you need it.

For us the choice of wing sails also came down to what produces most thrust and is going to withstand year-in-year-out of operation in harsh conditions. The wing sail is what we anticipate will give us the most amount of effect for the best performance in real life.

How did you arrive at the wing sail solution?

ND: The reason we selected the wing sail relates to the vision. The vision is really about making a change and developing a fully sailing ship. Then you need, in my view, a wing sail. You can’t do that with a rotor sail or other [solutions]. The advantage with wind sails that you have compared to other [solutions] is that we can take the wind much closer to the bow. This means you have much more operability. We are sailing up to 5-10 degrees from the bow. To have the operability in combination with having forces that has been the main reason [for wing sails]. Then in the longer term we want to have a fully sailing ship and we don’t see how that will be really possible [with another solution].

What is the payback period on a retrofit of the wing sail technology?

ND: It’s very difficult in general because we are in the test phase of this part. It means that we don’t really have the full cost. Of course, we understand what the cost levels are today but it is also like a prototype. And then of course what will that be in effect when you have serial production? This [cost] will be something that will go down.

RS: I think the answer to the question is that it’s highly subjective. It depends on the size of the vessel and the operating conditions amongst many other factors.

ND: [The payback period] is very route and vessel specific. If I give a number and then it will be half that number for one vessel and double that number for another.

Oceanbird Managing Director Niclas Dahl and Wallenius Wilhemsens VP Global Sustainability Roger Strevens Image <strong>shipenergy<strong>

When it comes to complying with regulations, much of the focus centres on alternative fuels. To what extent can wind propulsion become a commercially viable means for decarbonising maritime operations?

RS: The frame of reference for shipping is changing. It is being driven by regulation, demand changes and innovation and is what is determining what propulsion solutions will remain viable and which will become viable. To illustrate the importance of the frame of reference, consider how the 2020 global sulphur cap created an overnight, 200 million tonne market for VLSFO. Without regulatory change that wouldn’t have happened.

Another frame-of-reference changing regulation is CII [Carbon Intensity Indicator]. What have owner/operators got to work with? They can make modifications to the hull and propeller – if those options haven’t already been maxxed out. Changing operational aspects, like reducing speed and / or the number of ports called, is another option but obviously those would disrupt the service they can offer customers. A third option is to also look at using reduced GHG WtW [well-to-wake] fuels, but that raises issues relating to cost and availability. What’s intriguing about wing sails is that they are based on the fact that while all vessels need energy for propulsion, they don’t all need fuel all the time. Reducing the amount of fuel needed reduces all the challenges related to fuel and compliance. This point is all the more important when you consider CII is not a one-time deal. It gets tougher year after year. We know that’s going to happen up until 2026 and I think it will be very foolish to believe that it’s going to stop there.

One of the criticisms of CII is that it disproportionally impacts different vessel segments. As a car carrier, how does it affect Wallenius Wilhelmsen?

RS: There are issues with the regulation but one thing you can’t escape is that you have to play the hand of cards that you’ve been dealt. You can fault it all you like but meanwhile it remains. At Wallenius Wilhelmsen we are deeply engaged in addressing CII.

The Orcelle Wind is scheduled to start operations at the beginning of 2027. Can you sketch out a timeline for the next four years?

ND: From our side, we will look into whether we should go into different segments and if it’s interesting to look more into the car carrier fleet in general. That means we will go into a more commercial approach, basically from 2024 I would say.

For us, we have seen a lot of different numbers coming in about how big this market will be. What I have seen is that it will be about 10% of the existing fleet that would go for a wind installation. In my view that sounds reasonable. You will talk about maybe a few hundred ships per year, not thousands. Then, of course, it will always depend on if we have 20 competitors or, as seen in the ballast water treatment space, 70 competitors. What is important for us is we want to have a market leading position – that’s what we’re going in with. We feel comfortable; we have great mother companies that can support us.

RS: In building a full Orcelle Wind vessel, which will have six wing sails and be purpose-built for wind propulsion, there are two pivotal questions. One is meeting all of the design and engineering challenges – and we’re progressing nicely through that. The second is demonstrating there is a viable business case for doing this. This is why we’re actively engaging our customers to identify what the enabling factors for creating a compelling and viable market offer are. It’s a very methodical, detailed approach and we’re invested – and investing – in making this happen.

The Tirranna retrofit is the next major milestone for us and we are going to be closely involved with Oceanbird to develop the crew training from the land-based installation in the lead up to it.


Rhys Berry