FEATURE: How will the latest wind-assisted propulsion vessel projects influence future decarbonization strategies?

Renewable and free, wind power looks set to play an important role in future decarbonization strategies. E&H Marine rounds up some of the latest wind-assisted propulsion vessel projects.

As the focus on climate challenges grows, the latest International Maritime Organization greenhouse gas (GHG) emission reduction targets call for a 40% decrease in emissions (compared with 2008) by 2030, rising to 50% in 2050. With the shipping industry responsible for around 3% of GHG emissions globally, there has never been a more pressing time to adopt more efficient means of motion. Redeployment of wind power is the simplest form of propulsion, utilizing the latest technologies such as wing or rotor sails and parafoil kite systems to deliver vessels that are more efficient and less polluting.

Bar Technologies WindWings
Engineering solutions consultancy BAR Technologies (BARTech) has partnered with Yara Marine Technologies to bring the former’s WindWings technology to market. Full DNV type approval was granted in June 2023. Each wing is 37.5m tall, with a central section 10m wide and two movable outer sections, each with a width of 5m. The structure can also move as a whole and folds down for canal passage or port entry.

Four WindWings were installed on the Berge Bulk Newcastlemax carrier Berge Olympus in 2023. Each has a total surface area of 3,000m², and the four-wing setup is predicted to bring overall vessel savings of 6 tons of fuel and 19.5 tons of CO² emissions per day on an average global route. Berge Bulk is also evaluating the potential of installing additional WindWings on some of its other vessels that ply routes with potentially more favorable wind conditions.

The technology was first deployed on Mitsubishi Corporation’s 80,962 DWT Pyxis Ocean bulk carrier vessel as part of a collaboration between US firm Cargill and MC Shipping. One of the ship’s pair of WindWings was funded by the European Union as part of the Horizon 2020 project CHEK, which is dedicated to demonstrating solutions for the decarbonization of international shipping.

It is claimed that WindWings – which also uses route optimization – could increase vessel fuel efficiency in excess of 30% depending on retrofit or optimized new-build hull installation. Although the technology is initially aimed at bulk carriers and tankers, BARTech is developing additional models for other large ship types. The company has already secured two signed contracts for work on new vessels. The Aframax/LRII project with naval architect Deltamarin will include four WindWings and a hull form optimized to maximize wind power. It is forecast to improve performance by 15% through wind propulsion.

MOL Wind Challenger
Developed by Japanese transportation company Mitsui OSK Lines (MOL) and Oshima Shipbuilding, the Wind Challenger is a telescoping hard sail. Made from glass-fiber-reinforced plastic (GFRP), it is 53m tall in four-tier configuration, with a width of 15m. As with other hard-sail systems, control is automated. The sail uses sensors to detect the speed and direction of the wind. It shrinks if the wind is too strong and extends once the air speed is more suitable. The sail automatically rotates to optimize power.

The world’s first cargo vessel fitted with the Wind Challenger system – the 100,422 DWT MOL Shofu Maru coal carrier – was delivered on October 7, 2022. A dedicated Tohoku Electric Power vessel, the MOL Shofu Maru sails between Australia, Indonesia and North America. It is expected that the Wind Challenger will reduce GHG emissions by 5% on a Japan-Australia voyage compared with a conventional vessel. Potential savings on a Japan-North America West Coast voyage are claimed to be even higher, at 8%.

A second bulk carrier fitted with a Wind Challenger is planned for delivery in 2024. The MOL system is also being evaluated for use with other technologies, such as Anemoi rotor sails, to reduce GHGs by an average of 20%. UK renewable energy company Drax Group and MOL Drybulk are studying the feasibility of deploying first- and second-generation environmentally friendly bulk carriers (EFBCs) to carry Drax’s biomass. Expected to arrive in 2025, the first vessel will employ Wind Challenger technology, with research into other more efficient systems – including rotor sails – underway.

MOL is also developing green technology as part of its Wind Hunter project, which combines wind propulsion sailing systems and wind energy to generate electricity to produce hydrogen. This is then used as a fuel cell under weak wind power conditions. A 60-70m prototype with multiple hard sails will be constructed during 2024, with expectations for the Wind Hunter technology to be introduced commercially in 2030.

Anemoi rotor sails
Looking very different from modern sail wings that more visually resemble traditional sails, vertical cylinder rotor sails leverage wind power for extra forward thrust, helping to improve energy efficiency and carbon emissions. UK company Anemoi Marine Technologies first had the idea for its rotor sails in 2007. However, the technology originally dates back to the 1920s when German engineer Anton Flettner invented the Flettner rotor concept. Available in heights of 24m, 30m or 35m – all with a diameter of 5m – Anemoi’s rotor sails are manufactured from composite materials with steel towers, and are systems automatically controlled from a vessel’s bridge control unit (BCU).

In 2022, Singapore-based dry bulk owner Berge Bulk signed agreements with Anemoi to supply and fit two of its vessels with rotor sail technology. Four folding rotor sails will be installed on the 388,000 DWT Valemax Berge Neblina ore carrier and the 210,000 DWT Newcastlemax Berge Mulhacen bulk carrier vessel. Forecasts show that 1,200-1,500 metric tons of fuel per vessel per year can be saved.

In June 2023, a trio of 24m rotor sails was retrofitted on board TR Lady, a Kamsarmax bulk carrier, with expected annual fuel and emissions savings of 10%.

The latest Anemoi rotor sail installation will be on a 400,000 DWT Valemax ship operated by Brazilian shipping company Vale. Owned by Omani shipowner Asyad, the Sohar Max VLOC is the world’s largest ore carrier. The agreement between Anemoi and Vale will see five Anemoi rotor sails mounted on board the ship using Anemoi’s bespoke folding deployment system. This will be the largest wind propulsion installation ever, with the outfitting of the 35m sails expected to be complete in Q2 2024.

Airseas Seawing
Founded in 2016, French company Airseas has been testing its supplementary propulsion Seawing kite or parafoil wing on vessels since 2021 and has recently passed a major technical milestone. Successful validation of traction flights on the Ville de Bordeaux ro-ro cargo ship have provided the first tons of traction that aim to reduce fuel consumption and emissions. This result shows that the Seawing system is working as planned.

“Until now, we had validated the take-off, ascent, descent and landing phases of the wing,” says Mathieu Reguerre, Airseas’ flying components project manager. “During this latest phase, we managed to lower the wing on the horizon to enable the kite to deliver traction that would help propel the vessel.” Projected fuel savings calculated from the tons of traction measured on the Seawing system during the latest trials are as much as 16%.

The 1,000m² sail surface harnesses wind power to ‘tow’ ships. The latest test helps to progress the Airseas Seawing project, which is still undergoing sea trials on real commercial voyages across the Atlantic Ocean on board the 5,291 DWT vessel operated by Louis Dreyfus Armateurs, with support from Airbus, which charters the ship to transport aircraft components between Europe and the USA.

The commercialized product will operate using an automated flight control system that makes constant adjustments to the Seawing’s position and trajectory according to a number of factors including ship speed, weather and wind conditions. Traction forces are multiplied as the kite flies figure-of-eight patterns 300m above the sea. With automated take-off and landing now fully operational and the validation of traction flights complete, the next phases of the Seawing project will focus on dynamic flights, gathering performance data and fine-tuning the automation system.

Airseas has recently announced plans for a 2,400m² R&D center in Morocco for continued land and sea tests and development of the Seawing system. Further plans include the opening of a production facility in 2026, as the project accelerates toward full production levels. Airseas states that Seawing will minimize fuel consumption and greenhouse gas emissions on commercial ships by an average of 20%, and up to 40% on certain routes.

Norsepower rotor sails
Like Anemoi, Norsepower’s rotor sails use Flettner rotor sail technology for wind-assisted propulsion. Made from lightweight composite material with a fully automated control system and a maximum height of 35m, Norsepower’s rotors produce thrust as the wind generates differential pressure around the slewing rotor while the vessel is sailing. Manufacturing of The bulk carrier Camellia Dream is one of a number of rotor sail projects planned the sails is being scaled up to meet demand, with European production capacity forecast to reach 20 units in 2023. The capacity for China is stated to be as high as 50. 17 units have been delivered since 2014.

A contract with global shipping company IINO Lines will see the installation of two rotor sails on a new-build very large gas carrier (VLGC), with the 20 x 4m sails installed side by side. They have been specially developed for the vessel, accommodating its air draught limits. Installation will be complete in Q2 2024. IINO Lines has also agreed fitment of a 24 x 4m Norsepower rotor sail on the Yodohime coal cargo vessel. Scheduled to take place in Q3 2024, the project is in collaboration with J-Power and will be the first use of a Norsepower sail on a coal cargo vessel anywhere in the world.

Norsepower has also announced a new deal with MOL and Vale International to retrofit a 200,000-ton class bulk carrier – currently sailing under a mid-term contract for transportation of iron ore for Vale – with a pair of 35 x 5m rotor sails. This installation is expected in the first half of 2024, with projected fuel savings of 6-10%.

This article was originally publishing in the January 2023 issue of Electric and Hybrid Marine Technology. To view the magazine in full, click here.