The blue-hulled vessel would slip by unnoticed on most seas if not for the white kite, high above her prow, towing her to what its creators hope will be a bright, wind-efficient future. The enormous kite, which looks like a paraglider, works in tandem with the ship’s engines, cutting back on fuel consumption, costs, and carbon footprint.
“Using kites you can harness more energy than with any other type of wind-powered equipment,” said German inventor Stephan Wrage, whose company SkySails is looking for lift-off on the back of worldwide efforts to boost renewable energy.
The 160-square-metre (524-square-foot) kite, tethered to a yellow rope, can sail 500 metres into the skies where winds are both stronger and more stable, according to the 38-year-old Wrage.
The secret to the kite’s efficiency lies in its speed and computer-controlled flight pattern.
The idea is for the kite to describe figures of eight, which increases airspeed, said Wrage, who has been working on the new technology for 10 years and who still enjoys flying kites on the beach for fun.
“If you double the airspeed you multiply the energy by four. That’s the secret of the system,” he added.
A new 320-square-metre kite, recently produced, “has a towing force of 32 tonnes which is more than what two engines on an A320 Airbus (aircraft) can produce. So we’re not talking toys,” he said.
The kite towing the 87-metre-long ship Theseus would produce a maximum of 16 tonnes of thrust in perfect wind conditions. Retailing at half a million and one million euros (715,000 to 1.3 million dollars), the kites allow fuel savings of 15 to 25 percent depending on wind and shipping routes, said Wrage