Introducing Oceanbird, a wind-driven PCTC

September 16, 2020, by Jasmina Ovcina Mandra

Sweden-based Wallenius Marine is working on the development of a revolutionary ship design, which promises to cut emissions by 90% when compared to the best in class vessels of today.

The vessel concept, named Oceanbird, featuring a wind-powered Pure Car and Truck Carrier (PCTC) able to carry 7,000 cars in its hull, was presented in a webcast on September 10.

Aside from Wallenius Marine, which is the project coordinator, the Swedish collaborative project is being implemented by the Royal Institute of Technology (KTH) and SSPA. It is supported by the Swedish Transport Administration, which is acting as a co-financier.

KTH is addressing the challenges within areas such as aerodynamics, sailing mechanics and performance analysis. SSPA is contributing with expertise within the development and validation of new testing methods, aerodynamic and hydrodynamic simulation methods and risk simulation.

Described as the world’s largest sailing vessel, the first full-scale vessel from the project is expected to be delivered at the end of 2024.

The ship is designed to be suitable for any deep-sea operations. The North Atlantic has been selected as the starting trade route for the ship.

A transatlantic crossing with Oceanbird will take around twelve days, compared with the eight days it takes conventional vessels, the project developers estimate.

With the current design, the vessel is 200 metres long, and 40 metres wide
Estimated average speed 10 knots
Height above waterline 105 metres

The specially designed hull will be fitted with five wing sails, each at around 80 meters high, twice the height of those on the largest sailing vessels around today.

The design features a mix of aerodynamic used in aeroplanes and shipbuilding technology.

The rigging is made of steel and composite materials and turns 360 degrees to catch the wind in an optimal way.

It will be possible to ‘reef’ the wing sails, reducing their height with approx. 60 meters. The hight above the waterline with the wing sails down will be 45 meters.

The wing sails will be autonomous to a certain degree, however, the company is not planning to make the entire ship autonomous as it believes this would overburden the ship with novel technology.

Nevertheless, when it comes to crewing, the ship would need a somewhat different crew composition due to the technology installed on board.

The company anticipates the wings would be built by an external supplier and delivered to a yet-to-be selected shipbuilder that would be entrusted with constructing the first ship from the project.

The vessels will also be fitted with engines to enable them to maneuver in and out of port, and for an emergency operation.

During those operations, the sails would be lowered, so the ships could move around more easily, avoiding potential infrastructural hurdles to free navigation.

The company is yet to decide on the type of fuel that would be used once the ship is built.

“We will bring energy on board in some kind of fuel, but we don’t know yet what that fuel will be. We will follow the technology and use the most feasible, and best fuel available on the market, with the lowest level of emissions as possible,” Per Tunell, Chief Operating Officer, Wallenius Marine, said during the webcast.

Tunell believes the market readiness for this type of vessel is increasing with the greater pressure from consumers and regulators for shipping to become more sustainable.

“With Oceanbird we will take a leap towards our vision. We have been pushing the sustainability agenda in shipping for decades, and it has been quite challenging sometimes. Over the last few years, there has been a growing demand for sustainable solutions, so I am convinced now is the right time to do it,” he pointed out.

Tunell admits the ship would most probably be an odd sight once it starts sailing the seas. That being said, he is very optimistic about the ship’s future given the overwhelming support from the key stakeholders involved in discussions with the project developers. These include ship operators, cargo owners, ports, and authorities, he said.

From a technical perspective, the most challenging aspect was getting the wing rigs, the hull, and all other different components to work together as a one, integrated unit, Carl-Johan Söder, Design Manager Wallenius Marine, said during the webcast.

“Definitely, the wing rigs and getting a set-up where you have sufficient efficiency, but also the ability to generate enough power and de-power in a safe and robust way was very demanding,” he added.

“Normally, when you optimize the hull of a cargo ship, your number one priority is to minimize the drag. But there is also a need to take care of the big side forces that are generated by the wing rigs. We do that with the number of immovable fins, which compensate the side forces so that the hull can go straight through the water, instead of having a side slip or a drift angle,” he said.

Wallenius Marine started looking into potential zero-emission solutions for shipping ten years ago, and after researching different solutions, the company’s engineers and naval architects concluded that the renewable energy source with the most potential was wind power.

An investigation into wind power potential has found that only fixed wing sails would meet the company’s stringent demands for performance, sustainability, and durability.

In 2018, Wallenius Marine partnered up with KTH and SSPA in a cluster of competence to develop the project.

In 2019, economic and technical simulations and tests followed suit, with projects like measurements of wind speeds at high altitudes at sea taking place as well.

In summer 2020, the first PCTC hull model was put to the test at sea.

“The development project has come very far. We have started testing with 7-metre models in open water recently and will continue this fall. The design will be ready for orders in 2021 and we are aiming for a possible launch in 2024,” Richard Jeppsson, VP Commercial & Partnership, Oceanbird, said in a comment.

According to Jakob Kuttenkeuler, professor of naval architecture at KTH, testing of the 7-meter models is being used to practice maneuvers at sea and verify performance predictions of simulation tests for different situations.

“Well, from the perspective of a technical university, this is the engineering dream and it’s also probably one of the most thrilling projects that I personally been involved in during my career,” he said.

“This is an optimization challenge. We are seeking the sweet spot here between emission-free sailing and achieving reliability of the boat at the highest speed possible.”

Commenting on the support from the Swedish Transport Administration, Tunell said that the assistance has made it possible to kick start the project, shortening its delivery time by several years.

Likely construction cost for the vessel is not expected to exceed much the one assigned to a traditional vessel from the class. However, as Tunell explained, the developers don’t have the full picture of the cost yet. It will likely be slightly more expensive than a traditional vessel, with a premium being spent on the wing rigs.

From a business model perspective, different factors would have to be considered when compared to conventional vessels.

These include less bunkering, longer lead times, and potential routes and port rotation operators might choose for the ships. Hence, different scenarios are being considered by SSPA to better understand different market potentials.

The car carrier sector is the starting point for this type of technology since Wallenius Marine knows this sector the best. Nevertheless, the company is planning to expand this concept into other sectors as well.