Japanese shipping firm Kawasaki Kisen Kaisha (K Line) has completed the first phase of development of its ‘Seawing’ automated kite system, designed to harness wind power and cut bunker consumption.

Its French subsidiary, Oceanicwing SAS, finalised phase one in June 2025 after successfully testing a 300 m2 kite at a land site, confirming tensile strength and performance, K Line said in a statement on its website on Thursday. 

Unlike rotor sails or rigid wing sails, which are mostly fixed structures, a kite-based system deploys a large parafoil kite from the bow of the vessel.

Once launched, it flies at a higher altitude in a dynamic pattern where winds are stronger, generating forward pull to reduce engine load.

K Line says that in favourable conditions, Seawing could cut bunker use by more than 10%.

Phase two began in July and will see larger-scale kites tested for strength, reliability, operability and safety, with shipboard trials planned on a large K Line bulk carrier.

The programme is expected to take about two years, aiming for practical application by around 2027.