In view of the upcoming decarbonization goals for shipping, wind can be a free, abundant and infinite fuel that can assist in reducing GHG emissions and improve energy efficiency. Wind-Assisted Propulsion Systems (WAPS) take advantage of the available wind to generate forward thrust, thus reducing the engine thrust required and consequently reducing fuel consumption and emissions. bound4blue developed the eSAIL based on the suction sail technology, invented and tested onboard in the 80s by Professor Lucien Malavard and Dr. Bertrand Charrier under the initiative of the Jack Cousteau Foundation.
The eSAIL technology
The eSAIL aerodynamic performance was validated both with CFD modelling and several wind tunnel testing campaigns and presented at RINA Wind Propulsion Conference in London. The first installation was onboard a fishing vessel in 2021 and Bound4Blue are currently working on several other projects for different vessel types and sizes (general cargo vessel, Ro-Ro, tanker, bulk carrier).
Size: the eSAIL has a higher lift coefficient; in other words, it can deliver the same propelling force with six to seven times less surface, this is why the size is much smaller than the size of rigid sails and similar to that of rotor sails.
Operation: The operation of the eSAIL is simple and automatic, having an excellent capacity to sail upwind. The material used is steel for two main reasons: lower price and ease of production and repair.
Maintenance: There are no vibrations or moving parts, therefore the requirements for maintenance are minimal.
Depending on the vessel’s route, eSAIL can be a cost-efficient solution with an excellent payback time, since power consumption and CAPEX are low.
Type of vessels – routes
The performance of Wind-Assisted Propulsions Systems heavily depends on wind conditions, which are defined from the trade routes of each vessel. As a first step to evaluate whether eSAIL is a suitable solution for a specific vessel, bound4blue provides a preliminary case analysis to define the potential fuel and CO2 savings over selected trades based on 10-year historical wind data.
For more information, contact Oceanking, Miltos Messinezis.