Application of an Automated Kite System for Ship Propulsion and Power Generation

SkySails develops and markets large automated towing kite systems for the propulsion of ships and for energy generation. Since 2008 pilot customer vessels have been operating propulsion kites in order to reduce fuel costs and emissions. In this contribution the SkySails towing kite technology is introduced and an overview over its core components kite, control pod, towing rope, and launch and retrieval system is provided. Subsequently the principles of force generation and propulsion are summarized. In the following part the system’s application to airborne wind energy generation is presented, where the kite forces are used to pull the towing rope off a drum, powering a generator in the process. When the maximum tether length is reached, the kite is reeled back to the starting point using the generator as a motor. A functional model was constructed and successfully tested to prove the positive energy balance of this so-called pumping mode energy generation experimentally. An evaluation of the technology’s market potential, particularly for offshore wind farms, concludes the contribution.