Bureau Veritas has completed a design assessment of Bound4blue's Model 3-24 eSAIL suction sail, providing independent recognition of the wind propulsion technology. The assessment was presented during a handover ceremony at SMM 2026 in Hamburg.

The milestone comes as Bound4blue's eSAIL systems reach 13 operational vessels, with six further installations in its orderbook and more than 50 units ordered overall, the company said in an emailed statement on Tuesday. Independent design assessments of this kind are an established step toward class approval for wind-assisted propulsion, giving shipowners and yards a recognized technical basis for installing the systems on commercial tonnage.

The Model 3-24 was commercially installed earlier this year on Klaveness Combination Carriers' Baltazar. The Model 3 range covers sail heights from 24 to 36 m and is designed for larger vessels.

According to Bound4blue, its suction sails can generate up to seven times the propulsive force of rigid sails of the same size and deliver double-digit fuel savings. Such savings matter to operators facing tightening regulatory pressure, including the IMO's greenhouse gas reduction strategy and the EU's FuelEU Maritime regulation, which both reward lower fuel consumption and emissions intensity. Wind-assisted propulsion has accordingly attracted growing interest as a fuel-saving measure that works with, rather than replaces, existing machinery.

The system can be installed on both newbuilds and existing vessels and can operate alongside conventional propulsion. It can also complement future-fuel strategies based on methanol and ammonia, where reducing baseline fuel demand can help cut the cost and supply burden of more expensive alternative fuels.

Source: Ship & Bunker (https://shipandbunker.com/news/world/642184-bureau-veritas-assesses-bound4blue-wind-propulsion-system)