Wind assisted propulsion systems (WAPS) company bound4blue has completed the installation of four 22m eSail suction sails onboard Marflet Marine’s ‘Santiago I’, positioning the company as the first Spanish merchant fleet owner to commit to WAPS and suction sails.
The installation, completed at EDR Antwerp Shipyard following ‘wind ready’ preparation work at IMC Shipyard in Zhoushan, China, transforms the 49,999 dwt chemical tanker into what bound4blue describes as “a flagship for Spanish maritime innovation”. Engineering support for the project was provided by Cotenaval.
Signed in May 2024, the original contract represented an important milestone for both companies. Now operational, Santiago I is expected to reduce annual energy consumption by approximately 10-15%, depending on trading patterns and weather conditions. Alongside lower fuel consumption and reduced GHG emissions, the installation will help lower exposure to carbon costs under the EU ETS while supporting compliance with FuelEU Maritime.
José Miguel Bermúdez, CEO and co-founder, bound4blue, said: “Seeing Santiago I enter service with our eSail technology onboard is a particularly proud moment. It brings together two Spanish companies committed to demonstrating that innovation developed at home can help shape the future of international shipping. Marflet Marine showed real leadership by becoming the first Spanish merchant fleet owner to embrace wind-assisted propulsion in 2024. Today that vision has become reality. It’s another example of how practical, scalable technologies are enabling owners to improve efficiency, reduce emissions and strengthen competitiveness without fundamentally changing the way their vessels operate.”
The fully autonomous eSail system generates additional propulsive force by drawing air across an aerodynamically optimised surface, creating lift up to seven times greater than conventional rigid sails of the same size. By significantly reducing main engine load, the non-Atex technology lowers fuel consumption and associated emissions while requiring virtually no additional workload, and minimal maintenance, from onboard crews.
For Marflet Marine, the installation marks another step forward on its journey towards more sustainable shipping operations.
Juan Cremades, Fleet Director, Marflet Marine, said: “We committed to this project because we believed wind-assisted propulsion offered a practical way to strengthen both environmental performance and commercial competitiveness. We’re really excited to see those benefits take shape onboard Santiago I as it sails into a new age of operation – demonstrating how investment in proven innovation today can deliver lasting value in the years to come, both for our own business and the wider industry. Given our confidence in this technology, our next step will be to order additional eSails for other vessels in our fleet.”
Designed for both retrofit and newbuild projects, bound4blue’s DNV type approved eSail systems are suitable across a range of vessel segments.
Image: Marflet Marine’s ‘Santiago I’ equipped with four 22m eSails following installation at EDR Antwerp Shipyard (source: bound4blue)



