How the sail is being reinvented to power modern ships

The International Maritime Organization has set the industry a target to reach net zero status close to 2050. Emma Keeling is in Stockholm, Sweden – where Oceanbird is reinventing the sail to power modern ships. The Swedish company was born from global shipping company Wallenius Marine’s desire to eliminate emissions. Oceanbird wingsails can be retrofitted on all kinds of ships – containers, tankers and possibly cruise ships. But they won’t just be retrofitting vessels – they’re also building a brand new car carrier – that will run mostly on wind and launch in 2027. Oceanbird says each sail could save up to 675-thousand liters of diesel a year – or about 1920 metric tons of carbon dioxide.

How big are those big boats that you’re going to be putting these on 230 M it doesn’t look so impressive in this but imagine when you scale up all then you will also understand the wing size the maritime sector is mobilizing to hit Net Zero emission targets by around

2050 low carbon liquid and gaseous fuels will play a part but many including shipping companies are taking inspiration from their fourbears and a 5,000-year old technology catching the wind so this motorboat this is the past and that is the future we’re now out on the water in Stockholm where ocean bird is also

Adapting the sale the Swedish company was born from global Shipping Company Venus Marines desire to eliminate emissions but ocean bird won’t just be retrofitting vessels they’re also building a brand new cargo ship that will run mostly on wind Nicholas D is the managing director so you think of

The maritime industry and it’s very polluting it’s going into the air it’s going into the water and there’s the noise pollution as well so what difference will ocean bird make do you think mean ocean bird will play an important role I think in general wind will play an important role we don’t

Want to put in a new environmental issue by solving the one that we have and that’s always the risk when you have some kind of burning fuel you will always get some residuals so this is a completely natural way of of taking the ship forward this is a research model but

Computer simulations can provide accurate numbers of what fullscale vessels could save so what kind of savings will These Wings Are have or make it’s always difficult when you talk about savings it’s depend on the route it depends on what kind of ships you put

Them on and so on but in this case if you take a large car carrier that this would represent and on a favorable route then we talk about I mean 7 10% of savings so quite substantial for One Wing ocean bird says each sale could save up to

675,000 L of diesel a year or about 1,920 metric tons of carbon dioxide here’s how they work the wings consist of a main cell and a flap 40 m high and 14 M wide they form an asymmetric shape where the wind on the outer part accelerates but decreases on the inner

Part that increases the lift which thrusts the ship forward the sails can even be rearr range to create what’s known as cber a curved angle that helps generate even more force and the wings can also be folded down flat on the deck I’m just looking at this 7 m model and

I’m just imagining how big are those big boats that you’re going to be putting these on 230 m is the scale for this one wow it’s actually hard to imagine yeah it doesn’t look so impressive in in this but imagine when when you scale up all then you will also understand the Wing

Size ocean bird says the first vessel retrofitted with one of their wings will Sail by 2024 and the new ship a car carrier with six Wing Sals is expected to go on its maiden voyage in 2027 but there’s more research to do with PhD students from kth Royal

Institute of Technology and ocean bird testing energy forces including using the 7 m model you got sensors everywhere right what are you attaching here on the sale we are connecting all the electronics because we have one so-called Captain one main computer on board that’s somewhere in the middle but

All the other ones uh the other com computers little microcontrollers they help collecting all data from the wings with sensors in the wings as well and send all data to the Capal and how much data will you I mean you’re just Gathering everything you possibly can yeah indeed because experiments you you

Can never exactly plan now it’s much more winter than we expected so so we will collect different data than it was anticipated and of course we do usually particular tests so for example we could uh Sail on a constant course and change the angles of Attack Of The Wings and

See what pressures we get over the profile um that was the propose in the last test and the idea with this was to um figure out the aerodynamic interactions between the wings a lot of work took place on land as well the sales have been tested in a

Wind tunnel to understand the physics that could let them Propel even the largest ships at sea ocean bird says even small changes to the environment could significantly change the aerodynamics you’ve done a lot of testing in Wind tunnels as well but I mean nothing beats actually coming out

On exactly because the conditions in the Wind Tunnel even even though we have real wind and it’s not simulated or so are way too perfect uh we have constant inflow over the entire wing and now real wind is changing all the time in all directions in speed in angle everything

And uh something like that we cannot reproduce exactly in the Wind Tunnel this model has been running tests for 3 years and the Sals themselves have changed so the model that we’re looking at at the moment and the wing sails they’re different from the ones I’ve

Seen which have a flap so this is an older design you see the steps on the wings the idea was to make it telescopic so that you can reduce the sail area by retracting it into itself but now with the flap the wing is actually much smaller it’s less high but approximately

The same uh efficiency so we can be as performant with a smaller Wing so is there actually any point in in testing an old design I mean what are you going to learn from that on this model we’re measuring where the wind is coming from and then we calculate an angle where the

Wind should be in order to have a fixed angle of attack in that case but the wind is changing all the time so here there’s a computer calculating this all the time and then adjusting the wings also all the time we also look at the entire boat and how it is sailing

Interesting to look at with those wings as well is the aerodynamic interactions between the wings so we have four wings in a row behind each other and they don’t see the same inflow but what we can do here we have sensors in the wings that measure the pressure distribution

And it depends on where which position on the boat a wing has how much force it can generate so that’s something we can study anyways no matter which shape of wing is this an exciting project to work on cuz in many ways you’re redesigning boats OB redesigning the way of

Propulsion yeah and indeed that’s a really cool thing to do oceanbird wants to retrofit its wing sales on all kinds of ships containers tankers and possibly cruise ships that’s EML kot’s job part of your role here is that your retrofitting ships with the ocean bird wings I mean I’m guessing you

Can’t just you know put a wing on and that’s that no that’s right uh these vessels were optimized for their cargo handling and what they are brought to to ship over the world so if you put on a wing sail you cannot really do this even it looks

Really simple here but you need to consider all the reinforcements that’s required in these areas in order to transfer the forces from the wing sail down to the vessel and what you need to consider here is the cargo handling as well these hatches are sliding sideways

So the only area you have place to put something on is between these hatches okay so it has to go in these places here spots and I guess these also fall down so you got to think ofo you can’t block the hatch no exactly um but the

Hatch is only opening in the center line so if you first fold the wing sail and then til it down you wouldn’t interfere with the opening in the hatches and you’ve got to figure out the configuration of where you’re going to put those Wing sails as well abely right

Otherwise it’s going to tip over and that would be your fault yeah unfortunately yeah we need to consider every aspect of it it has to do with the balance of the vessel as well uh because if you sail with these many units you will not only have a forward

Thrust but you will have a side Force hitting the hull and you need to compensate that with your Rudder so you need to make sure that the installed Rudder is efficient and capable of handling this side process in order to keep a stable course so it’s all about

Efficiency and you got to think about what time and the water as well cuz most want their their trade going from Route A to B quickly but you know will this be a slower method no it doesn’t have to be you can have the same objective to

Always be on time uh you can see the wings as a complementary use of your main propulsion so if there’s a little wind you will still be supported by your main engine and it allows it to be on time efficiency also extends to the wing Sals mechanics which are in a container

On Deck saving Precious Cargo space inside the hull so this is our hydraulic lab where we tried to get before we have ever everything up and running it feels very important for us to be testing on real Hardware the wing Sails are moved with multiple hydraulic cylinders so this one

Is then for the tilting part and this would then be for the flap where we also want to symbolize I mean or test how what angle and and how to push so just to make this clear one of these is going to just tilt it down and bring it back

Up again and this one is controlling the flap when it’s upright exactly okay and then we always rotate the wing in the right position to catch the wind to catch the wind so instead of in the old days when they’d be pulling on the ropes that’s your rope that’s my rope exactly

And of course it’s all operated by computer so this is actually the brain of the whole system and we then put down into the Container together with the hydraulic system to keep them very close because we want to have one place where you do the service and you can handle

All of those things at the same place so one of the in the container but will you also have another one close to the captain on the bridge exactly the system must be durable to withstand the conditions at Sea which is why I was taken completely by surprise

To see what the wing Sails are made of what do you see here is sections from our panels so what we are doing here is that we are testing the strength of the panel so you have what you call a sandwich design so it’s glass fiber on

The outside and glass fiber and then in the distance here you have a core that is then made out of recycled pet uh bottles so this has also been an important part for our sustainability uh work a great way to recycle thousands of these surely this would be thicker

Though no this is the the actual uh so what you have inside is a steel Mast and then you will then put the panel outside that’s I mean that looks like nothing yeah but when you have them than 40 m it’s still quite a big weight and uh and

This is also how you put the different laminat will you can create different strength in different direction so this is what you’re then on checking and testing there’s been a lot of debate recently about how new sustainable Technologies could actually be more harmful to the environment over time so

How long will ocean Birds Wing sails last we’ve done their life cycle analysis to say what kind of CO2 emissions do we have when we produce it and how fast is our Payback time and what we can see on this Wings is the fullly one including transportation and

So on we have a payback time of less than a year so it’s still um we will work to reduce that even further but I mean if you think of that these have a lifel length of 25 30 years um it’s quite impressive it’s quick payback it’s

A very quick payback from the CO2 emissions yeah we’ve been sailing for thousands of years the ability to cross the oceans has transformed human history but could the answer to climate change lie in harnessing the forces of nature once again this technology in many ways is in its infancy but there are other

Competitors out there doing this kind of thing isn’t there yes for the Wind Community I would say there are a lot of similar type of of wings but also the other types of um Wind Solutions so you know in the future will it be the survival of the fittest the very best

Will be the best yeah no but it’s not only about the technology I mean it’s also about how do you handle everything around it with the team around it how do where do you get the best measurements in order to trim the sale in the best

Way so gets as much performance out how do you handle service around the world um which is a very important part for the Marine industry because ships have a tendency to move around and you want to be able to get spare parts everywhere service everywhere and so so there is a

Complete package and then it will be natural that the few technology will survive in that way and also of the best uh companies I think it’s important for the whole Market because you cannot do this transformation yourself we can learn a lot from each other we need to

Build up competence with class societies I think it’s more recognition that they see wind as a really good potential for the future in order to reduce Emissions