The SkySails-System
The SkySails-System is an innovative wind propulsion system for modern shipping. It aims to reduce fuel consumption of modern shipping by utilisation of environmentally friendly, free-of-charge wind energy.
The SkySails-System consists of a fully automated towing kite propulsion and a wind-optimised routeing system. It is used offshore, additionally to the propulsion of the ship’s engine, if wind conditions allow.
The SkySails technology differs from conventional sailing systems, which fit the sail to a mast and thereby connect it to the ship, in that the towing kite of the SkySails-System is connected to the ship via a towing rope. Sail area and ship are thus separated from each other. The resulting characteristics of the SkySails technology offer ships an auxiliary wind propulsion with an entirely new performance spectrum: high performance, high practicability and high safety.
The SkySails-System consists of three simple main components: A towing kite with a rope, a launch and recovery system, and a control system for fully-automated operation.
- The towing kite generates propulsion power. The optimal kite shape for this is a parafoil, an aerofoil similar to that of a paraglider. The profile of the towing kite is designed in such a way that optimal aero-dynamic efficiency can be achieved at any wind speed. The specially designed attachment system of the SkySails-System transfers the tractive force from the kite onto the ship. It is fitted on every ship individually. The mounting system ensures the ideal alignment of the towing kite’s force at every route and wind direction. The traction forces are transmitted onto the ship via a towing rope.
- The SkySails towing kite is recovered and launched using a dynamically operating winch, which also serves as rope storage. The launch and recovery system launches and recovers the towing kite, control pod and towing rope fully automatically. It is installed on the port deck in the bow area. The towing kite is freely manoeuvrable, attached at only one point to the launch and recovery mast via the kite adapter.
- During launch a telescopic mast lifts the towing kite, which is reefed similarly to an accordion, out of a container. At sufficient altitude the towing kite unfolds to its full size and can be launched. The reef system launches the reef ropes till operating altitude is achieved. The recovery procedure takes place in reverse order. The entire launch and recovery procedure is carried out fully automatically and lasts approx. 20 mins. each.
The steering system of the SkySails propulsion operates fully automatically. The towing kite can be aligned according to the wind direction, wind force, ship route and ship speed. The steering system of the SkySails consists of the control pod and the control system.
Operating the control pod is similar to piloting a paraglider. It "pulls" to the left and right of the control chords. The aerodynamic profile of the towing kite is thereby modified and has an impact on the flight path. Both the mechanical control actuators as well as the electrics for the control of the kite are installed inside the control pod. The control pod features a modular design and forms the physical link between the towing kite and the towing rope.
The function of the control system is to control the SkySails-System automatically. It is similar to the autopilot of an aeroplane, in that data is collected via sensors and processed by the autopilot software. Subsequently, the software sends control orders to actors in the system, e.g. to those of the control pod.
A constant, powerful propulsion force is achieved with the aid of the routeing system, which facilitates the utilisation of advantageous winds and thus quick voyages and punctuality. The "routeing" system component consists of four modules: Weather Forecasting, Performance Calculation, Decision-making Model, and Route Recommendation.
- Modern meteorological methods make precise five-day weather forecasting possible. The macro weather conditions and weather trends can be forecasted for even longer periods. Thus, the routeing plays a key role in ensuring the system’s safety.
- Weather forecasting data is fed into the performance calculation. A prediction for the available power through the SkySails propulsion system can thus be made. Possible routes along with ship speed are calculated for the ship using the SkySails system.
The decision-making model incorporates the priorities set by the ship owner. On the basis of the performance calculation the optimal route is calculated automatically.
Subsequently, the predicted optimal route is translated into a series of waypoints, which the shipmaster can simply read off.
