Barcelona, Spain | December 9, 2025 – bound4blue, a global frontrunner in wind propulsion systems, has successfully closed a US$44 million funding round—the largest global investment in wind-assisted propulsion to date. This strategic capital, backed by major shipping families, maritime corporates, climate funds, and government capital, reinforces the industry consensus that suction sails are the leading solution for immediate, scalable, and cost-saving decarbonisation today.
The investment signals the company’s shift from technology validation to full industrialisation, enabling it to expand manufacturing capacity to supply hundreds of eSAILs® annually across parallel production lines in Spain and China.
Investment Backers & Industry Confidence
The funding round was led by OCTAVE Capital (affiliated with major shipowner IMC) and Katapult Ocean.
New investors joining the round include:
- Motion Ventures
- Odfjell family office (signaling strong belief from a current customer)
- ReOcean Fund (led by the Prince Albert II of Monaco Foundation and Monaco Asset Management)
Existing investors, including Shift4Good, GTT Strategic Ventures, KAI Capital, and CDTI (Innvierte SICC), also significantly increased their commitment.
“This funding enables us to expand capacity, accelerate our growth roadmap and advance new developments that will elevate both the technology and our services to the next level,” said José Miguel Bermúdez, CEO & Co-Founder of bound4blue.
Proven Technology and Commercial Traction
bound4blue’s patented eSAIL® suction sails generate usable thrust from wind, directly replacing part of a ship’s engine power and dramatically cutting fuel consumption and associated carbon costs.
The company has already installed the technology on seven vessels, with a further twelve ships in the orderbook, representing more than fifty sails in total. This rapidly growing client portfolio includes industry heavyweights such as:
Double-Digit Savings Confirmed in Service
The investment is underpinned by verified operational data confirming the technology’s effectiveness:
- Compliance: By reducing engine load and fuel burn, eSAILs® significantly improve regulatory performance under frameworks like CII, EEXI/EEDI, FuelEU Maritime, and EU ETS.
- Technology: The eSAIL® system uses a thicker aerodynamic profile and active air suction to generate lift forces up to six to seven times greater than a conventional sail with minimal power consumption, acting as an autonomous auxiliary propulsion system.
- Performance: Independent verification shows consistent fuel and emission savings, with voyage-leg peaks reaching up to 40% reductions (e.g., on Odfjell’s Bow Olympus).
The “Retrofit Decade” Solution
The investment highlights wind propulsion’s unique position as a near-term solution for the maritime industry, which is entering a “retrofit decade” with tens of thousands of vessels requiring efficiency upgrades by 2030.
Unlike alternative fuels, which require long-term infrastructure and engine overhauls, suction sails can be:
- Installed today on existing ships (retrofits).
- Easily incorporated into newbuild designs to achieve compliance from day one.
- Directly rewarded under new regulations like FuelEU Maritime, and significantly improve vessel ratings under the CII and EEXI/EEDI frameworks.
About bound4blue
bound4blue, founded in 2014 with headquarters in Cantabria (Spain) and offices in Barcelona and Singapore, is a global leader in automated wind propulsion systems. The company provides the eSAIL® system, a patented, autonomous, and validated solution that uses wind power to generate thrust, significantly reducing fuel costs and polluting emissions.
Widely considered the most cost-efficient wind propulsion technology today, eSAIL® is suitable for various vessel types, including Tankers, Bulkers, Gas Carriers, and Ferries, regardless of age. Since its first installation in 2021, bound4blue has deployed its system on seven ships, with an order book covering twelve more ships (representing over 50 eSAILs® in total) for industry leaders such as Eastern Pacific Shipping, Maersk Tankers, and Odfjell.
Source: bound4blue