bound4blue has completed the installation of four 22-metre eSAIL® suction sails on Marflet Marine’s 49,999 DWT chemical tanker Santiago I, making Marflet the first Spanish merchant fleet owner to operate suction sails. The retrofit is projected to reduce the vessel’s annual energy consumption by 10% to 15%, enhancing regulatory compliance and fleet efficiency.
Barcelona, Spain | September 3, 2026 – bound4blue has completed the installation of four 22-metre eSAIL® suction sails onboard Marflet Marine’s 49,999 DWT chemical tanker Santiago I, positioning Marflet Marine as the first Spanish merchant fleet owner to operate suction sails and champion wind-assisted propulsion.
The retrofit reached completion at EDR Antwerp Shipyard following initial “wind ready” preparation work conducted at IMC Shipyard in Zhoushan, China. Specialized engineering support for the milestone project was provided by Cotenaval. Originally signed in May 2024, the project marks a significant triumph for domestic maritime innovation. Now operational, Santiago I is projected to decrease annual energy consumption by approximately 10% to 15%, driven by prevailing trading routes and weather patterns. This reduction directly cuts fuel usage, lowers greenhouse gas emissions, and helps mitigate carbon exposure costs under the EU ETS while ensuring compliance with FuelEU Maritime frameworks.
Executive Perspectives on Domestic Maritime Innovation
“Seeing Santiago I enter service with our eSAIL® technology onboard is a particularly proud moment,” comments José Miguel Bermúdez, CEO and co-founder of bound4blue. “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.”
Juan Cremades, Fleet Director at Marflet Marine, echoes this sentiment “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.”
Autonomous Technology and Fleet Performance
The fully autonomous, DNV Type Approved eSAIL® system generates additional propulsive force by drawing air across an aerodynamically optimized 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. A single bound4blue eSAIL® is expected to reduce energy consumption by around 10%, while actively improving the vessel’s Energy Efficiency Design Index (EEDI) and Carbon Intensity Indicator (CII) ratings.
This project sits alongside a broader wave of maritime modernization, including related developments like the Cotenaval-designed newbuild supporting transport links in the Austral Islands, which received backing from the French Polynesian Government’s Appel à Manifestation d’Intérêt initiative.
Boris Piel, Technical Director at SNA Tuha’a Pae Shipping Company, notes: “This project demonstrates that innovation and practicality can go hand in hand. We are proud to be pioneering the use of wind propulsion on a vessel of this type and look forward to seeing the benefits delivered in operation.”
Global Momentum in Wind-Assisted Propulsion
The installation on Santiago I forms part of a rapidly growing series of high-profile contracts and deployments for bound4blue. The company has now deployed eSAIL® systems across 12 ships, with an additional six vessels currently in its order book, representing more than 50 total eSAILs®. Designed for both retrofit and newbuild projects, the technology is suited for a broad range of vessel segments, including tankers, bulk carriers, Ro-Ro vessels, ferries, cruise ships, gas carriers, and general cargo vessels, solidifying bound4blue’s leading position at the forefront of the industry’s new wind revolution.
About bound4blue
bound4blue is a wind propulsion technology company supporting the maritime industry in reducing fuel consumption and emissions. Its eSAIL® system is an automated suction sail that uses wind as a clean energy source to deliver direct thrust to vessels. Founded in 2014, bound4blue is headquartered in Cantabria, Spain, with offices in Barcelona, Singapore, Shanghai, and Suzhou. The company works with shipowners, yards, and industry partners across newbuild and retrofit projects. Its client portfolio includes Eastern Pacific Shipping, Maersk Tankers, Odfjell, Klaveness Combination Carriers, BW Epic Kosan, and Louis Dreyfus Company, among others.
About Marflet Marine
Marflet Marine is a privately owned company dedicated to the management, operation, and chartering of chemical tankers. Backed by a proud seven-decade heritage, Marflet’s forward-looking strategy relies on a technically advanced fleet, market agility, and a highly motivated team. The company promotes a culture of HSSQE excellence across all organizational levels, remaining fully committed to the safe maritime transport of liquid cargo. Through the continuous improvement of its procedures, practices, and controls, Marflet Marine firmly aims for zero incidents, zero spills, and zero detentions. Sharing deeply aligned values with its partners regarding quality, safety, and environmental stewardship, Marflet Marine operates one of the most technologically advanced IMO2 MR tanker fleets in the market today.
Source: bound4blue