SkySails is the pioneer of wind-assisted ship propulsion systems based on kites. The technology was successfully proven on board of sea-going vessels between 2004 and 2012. However, in order to make the biggest possible impact on the ongoing energy transition, SkySails decided to focus on the dynamic energy sector with its SkySails airborne wind energy systems for power production for the time being. The SkySails propulsion system for vessels is therefore currently not marketed anymore.
Wind is the cheapest, most powerful, and greenest source of energy on the high seas, and the best solution to turn shipping more sustainable. The wind-assisted ship propulsion system from SkySails uses the power of wind to tow ships with large kites. SkySails employed kites of up to 400 m², replacing up to 2MW of propulsion power from the main engine.
SkySails kites fly at altitudes of up to 400 meters and can thus take advantage of the strong and constant high-altitude wind that is not reduced by friction with the water surface. Besides, the flight maneuvers controlled by the autopilot and performed in front of the ship increase the kite´s airspeed to a multiple of the true wind speed. The SkySails propulsion system therefore generates five to 25 times the propulsive force per square meter of surface area compared to normal sails.
The ship’s officers operate the SkySails propulsion system using the control computer installed on the bridge. During flight mode, the autopilot software ensures that the kite flies defined patterns based on wind direction and velocity, as well as the speed of the ship, so that it generates optimal propulsion. The launch and recovery process is widely automated and requires only a few simple actions on the foredeck by the ship´s crew.
The towing kite is the heart of the SkySails propulsion system. Steered by the control pod, the towing kite performs regular dynamic flight maneuvers in the air in front of the ship to generate tractive force.
The control system consists of the control pod located underneath the kite and the control computer on the bridge. The control pod contains the autopilot system that steers the kite by manipulating the steering lines and airbrakes. The kite is aligned relative to wind direction, wind force, ship course and ship speed in order to achieve maximum tractive force.
The tractive force is transmitted to the ship through the towing rope. It is made of HMPE and especially developed for applications with a high demand for safety (e.g., cranes and lifts).
The launch and landing system manages the deployment and lowering of the propulsion kite. It is installed on the forecastle and consists of a telescopic mast with reefing system which unfurls and reefs the kite respectively during the launch and landing process. The launch and landing system is powered by a hydraulic power pack.