Reinventing Wind-Assisted Ship Propulsion
Some companies in the maritime industry have initiated a new turn to the wind as a complementary (or even exclusive) source of energy for ship propulsion. Three dominant technological implementations have already appeared at different readiness levels. Airseas is developing the Seawing propulsion system, which is an automated kite mounted on the bow of a ship and can be released to tow the ship using the power of the wind. In this way a 20% reduction of the working load of the ship's propulsion engines is achieved, as well as a 20% reduction of CO2 emissions. Wallenius Marine is designing the Oceanbird, which will use a more traditional implementation of wind propulsion in the form of sails. Its technologically innovative telescopic sails are expected to have a height of 80 meters, which is twice the height of the sails currently owned by the largest sailing boats in the world. Oceanbird will be able to cross the Atlantic Ocean in 12 days with 90% less CO2 emissions than a diesel vessel and will be used to transport cargo, mainly cars, as it has a capacity of 7000 cars. Finally, the most mature technological implementation of modern wind propulsion currently in use as a pilot demonstrator utilizes the Magnus effect. In 2018, the Fehn Pollux tested for the first time the ECO FLETTNER system developed with the support of DNV GL as an improved version of the Flettner pillar invented as a propulsion method a century ago. The ECO FLETTNER system is a rotating pillar that exploits the Magnus effect to convert side-wind into usable propulsion. The additional power provided to the ship through this system can lead to energy savings and a reduction in emissions from the basic propulsion system by 10-20%.