It's a great day for the Dutch shipping company Rederij Doeksen and its managing director Paul Melles as the new ferry Willem Barentsz finally goes into service on the large Dutch intracoastal Wadden Sea, joining the existing fleet. However, one thing distinguishes it from the other ferries: it is the first in the fleet to run on liquid natural gas – an important milestone for the shipping company director because protecting the Wadden Sea, which was declared a UNESCO World Heritage Site in 2009, is particularly close to his heart. He wants to make Doeksen's ferry operations as sustainable as possible. The task he has taken on is far from easy, with around eight hundred thousand people per year wanting to travel from Harlingen on the Dutch mainland to and from the islands of Vlieland and Terschelling, 30 kilometers away.
Pride and joy are written all over Paul Melles' face, as the shipping company is now one step closer to its ambitious goal. When it comes to being environmentally friendly, the new ship stands out among its competitors. The newly developed mtu natural gas engine already comes in significantly below the limits of current emission guidelines (IMO III) – without even needing to treat the exhaust gases. It emits no sulfur oxides and only small amounts of nitrous oxides.
The 16-cylinder mtu Series 4000 gas engines produce 1,492 kW of power and ensure that the ferry can reach its maximum speed of 14 knots. The shipping company will soon be putting a second identical ferry into service, also fitted with mtu gas engines.
In this interview, Paul Melles tells us what the new gas engines can do compared to diesels.
Congratulations on the successful commissioning of the Willem Barentsz. How does it feel to travel on a gas-powered ferry?
I am very happy with it so far. The gas engines are quiet and produce no vibrations or noise. You only hear the various ventilation fans onboard, of which there are quite a few on a passenger ferry. It also eliminates the unpleasant smell familiar from diesel engines. And there's no black smoke. These are all very pleasant characteristics!
And for the skipper? Is it very different to maneuver a gas-powered vessel as opposed to a conventional diesel?
The new ferry is the first vessel in our fleet to be fitted with gas engines. So that's a novelty in its own right. Our skippers have had to be trained to get used to the maneuvering characteristics of the vessel including the efficient Veth propulsion system. But we can already say that the gas engine shows similar dynamic characteristics as diesel, so maneuvering the ferry is not a major change.
To what extent does the Willem Barentsz contribute to greater sustainability?
The vessel is made entirely of aluminum, making it lighter and meaning it uses less fuel than conventional ferries. The engine Waste Heat recovery system is also a remarkable feature. Normally, the residual heat simply disappears into the air or is discharged into the sea, but the new LNG ferry is different. It has a residual heat recovery system which makes use of the thermal energy from both the engine’s cooling system and exhaust gas. The two Orcan units supply the entire electrical energy needs of the bow thruster system, as well as supporting part of the normal onboard electrical requirement. This avoids 318 metric tons of CO2 per unit per year, and saves 260,000 liters of fuel.
Was it difficult to install the gas infrastructure in the new vessel?
Setting up the gas infrastructure was a bit of a challenge, especially as passenger vessels have to have the highest safety precautions. Installing all the safety systems – the fans, fire protection and gas warning systems – and integrating them with the overall system took a lot of doing. But we managed it, and I can already say that once the system is up and running it is easy to handle.
Why did you go for mtu engines from Rolls-Royce?
Originally, we didn't plan to. I knew that Rolls-Royce was working on gas engines, but the impression I had was that our plan did not fit in with their R&D schedule, so we initially concentrated on a different engine. Then Wouter Hoek of MTU Benelux approached me and said Rolls-Royce was interested in working with me. He said they were willing to step up their efforts and select our project for the launch of their work on developing gas engines.
A good decision?
Definitely. I had full confidence in Rolls-Royce from day one. I've known the company for a long time. Rolls-Royce and its mtu brand are well known in the marine industry as specialists in high-performance engines. The company has really done a superb job on this project.
Why did you choose LNG as opposed to an all-electric ferry?
We thought about it, and came to the conclusion that it wouldn't be feasible. With its 1100-ton displacement and a 21 nautical mile route, the vessel would have needed a huge bank of batteries. There probably also wouldn’t have been enough time between sailings to allow the batteries to be recharged.
Have you had any negative comments about LNG?
I am often asked why we chose LNG (liquefied natural gas), which is still a fossil fuel. People are more interested than they are negative. I regard LNG as a stepping stone. At this point in time I think it's exactly the right fuel. It helps us comply with existing regulations, and it's cheaper than conventional fuels. LNG has an infrastructure already in place, whereas hydrogen does not, and that's a major benefit: to be truly market-ready, the infrastructure for a fuel has to be in place. The best idea would be to mix LNG with liquefied biomethane, or even replace it completely. That would make operation even cleaner.
Is there any prospect of LNG biogas being used soon?
I think we're on track for that. In the northern regions here, there are already plans to produce LBG biogas. It's good to see people actively promoting the project.
What will your fleet be like in the future?
Our next major project will be to review the existing fleet. We'll be replacing some vessels, but we will also be looking at retrofitting existing propulsion systems. Here we are open to different technologies, for example hybrid. The next steps will come in the next few years. We're confident there will soon be new legislation to do even more for the environment.