eSAIL®
The most cost effective
wind propulsion technology
Your challenge may be complex, but the solution doesn’t have to be.
At bound4blue, we have developed a modernized suction sail that turns wind into direct propulsion for your ship.
Our solution enables ship owners and operators to reduce their environmental footprint while cutting fuel costs. Because “good for the planet” can also mean “good for your business”.
How WAPS
work
Merchant vessels rely on the thrust delivered by their main engine for propulsion. These engines burn enormous amounts of fuel, resulting in large fuel-bills and pollutant emissions levels.
Wind-Assisted Propulsion Systems (WAPS) take advantage of the available wind to generate clean forward thrust, reducing the engine thrust required and consequently cutting down fuel consumption and pollutant emissions.
If WAPS are operated effectively to maximise forwards thrust under any sailing condition, double-digit percentages in fuel and emissions savings can be achieved.
Suction sail
operational principle
The eSAIL® produces six to seven times more lift than a conventional sail or, in other words, it can deliver the same propelling force with six to seven times less surface. All this with minimal power consumption and no mechanical complexity (no inertial loads, vibrations, constant movement, etc.) ensuring simple, safe and reliable operations.
When installed on a vessel, the eSAIL® technology is designed so that its high-lift ability maximises fuel savings in a cost-efficient way.
eSAIL®
parts
Fuel consumption reduced
up to 40%
Payback
< 5 years
Autonomous operation
No crew needed
The suction fan is a standard axial compressor driven by an electric motor. It is responsible for sucking in the air to ensure the airflow remains attached to the sail.
The suction area is a porous area of the skin through which the air is sucked. It is strategically designed and located to ensure airflow remains attached to the eSAIL® with minimal power consumption.
The geometry of the eSAIL® inverts depending on whether the wind blows from port or starboard. The flap is a movable structure, manufactured using marine-grade materials, that can be positioned on both sides of the eSAIL®, generating the appropriate aerodynamic shape of the eSAIL® and, at the same time, covering the suction area that is not in use. The flap positioning is achieved by means of standard electric motors.
The eSAIL® main structure and skin provide the external aerodynamic shape of the sail and, at the same time bear the loads that affect the eSAIL®. It is manufactured using marine-grade materials and also contains and protects the equipment located inside.
The rotation system ensures that the eSAIL® can rotate and make the most of any existing wind direction. It is based on a standard slew-bearing actuated by an electric motor. This part is very similar to a deck crane.
The eSAIL® mechanically connects to the vessel by means of a flange, which is secured using bolts. Again, this is a well-known solution, based on standard deck cranes.
Control
system
The eSAIL® is equipped with an autonomous control system that ensures optimal technology operation with zero crew workload or training. Based on the input data received from several sensors, the control system operates the three main trim actions – body rotation, flap position and suction – ensuring maximum fuel savings are achieved while guaranteeing safety.
A touchscreen is located on the bridge to monitor the status and operational parameters of the eSAIL®, also allowing to switch between different operation modes.
Tilting
system
If foldability is required, bound4blue also offers a tilting system to move the eSAIL® from a vertical to a horizontal position. This type of system is only intended to lower the air draft of the vessel in specific situations, as when sailing under bridges or during cargo loading and unloading operations.
Portfolio
General
layout
The optimum number of eSAILs® – defined during the vessel transformation project – will be positioned on the foundations and their flanges bolted together.
Weather sensors, capable of measuring various weather parameters like wind intensity and direction, temperature, and atmospheric pressure, are combined with GPS/inertial sensors capable of giving us several vessel navigation and attitude parameters. Sensor redundancy, as well as data accuracy, is achieved via a multi-sensor architecture.
The eSAIL® Main cabinet is the central part of the control system. It is located inside the eSAIL® body and contains the main equipment of the system (PLC, motor speed controllers, etc.). The eSAIL® Cabinet is the input for power supply (from the vessel) and it distributes this power to all control system elements.
All eSAIL® electronic components are interconnected via a closed Ethernet redundant loop that safely allows the operation of all eSAILs® from the main bridge or any other vessel location.
The Touchscreent is installed on the vessel’s bridge, allowing simple eSAIL® monitoring by the captain or any other crew member.