Amasus Shipping and bound4blue have completed the installation of a 22-metre eSAIL wind propulsion system on the general cargo vessel Fluvius Tavy at Astander Shipyard in Santander, Spain.

The installation marks the second collaboration between the Dutch shipowner and the Barcelona-based wind propulsion technology developer, following an earlier retrofit of two 17-metre eSAILs on Amasus' Eems Traveller.

According to bound4blue, the 22-metre unit is the largest suction sail ever fitted to a general cargo vessel. The company's eSAIL technology uses suction to draw air across an aerodynamically optimized surface, generating lift that the manufacturer claims is up to seven times greater than conventional rigid sails of comparable size.

José Miguel Bermúdez, CEO and co-founder of bound4blue, commented: "Our collaboration with Amasus continues to demonstrate that wind propulsion is gaining broader acceptance as a practical, profitable, and, crucially, a proven solution for an industry in transition."

He added that the installation is forecasted to "deliver significant double-digit reductions in vessel fuel consumption and CO₂ emissions."

The retrofit was completed during the vessel's scheduled maintenance period, with structural and electrical adaptations made to the deck before the pre-commissioned unit, manufactured in Spain by Haizea-Tecnoaranda, was installed in what bound4blue described as a streamlined, plug-and-play process.

Amasus stated: "The decision to install a second eSAIL reflects how satisfied we are with the performance and how smoothly it has integrated into our day-to-day operations. Our experience with bound4blue's suction sails highlights their suitability for short-sea general cargo vessels like ours."

The technology has received DNV Type Approval and has been retrofitted to vessels operated by other owners including Odfjell, Louis Dreyfus Armateurs, and Eastern Pacific Shipping, according to bound4blue.

The company, founded in 2014, reports it has deployed its eSAIL system on seven ships, with 12 more in its order book, representing more than 50 eSAILs. Its client portfolio includes Eastern Pacific Shipping, Maersk Tankers, Odfjell, Klaveness Combination Carriers, BW Epic Kosan, and Louis Dreyfus Company.

The project is part of the Spanish Naval Ecosystem PERTE and is funded by the European Union — NextGenerationEU through the Recovery, Transformation and Resilience Plan.