A new design for a sailing cargo ship with telescopically reefing hard composite sails could result in a third of the fuel use of a traditional capesize bulk carrier, says the vessel's designers, Professors Kazuyuki Ouchi and Kiyoshi Uzawa of the University of Tokyo, Japan.
The motor assisted sailing vessel would have nine carbon fibre-reinforced plastic sails 50 metres high and 20 metres wide giving a total sail area of 9,000 square-metres. The researchers confirmed that a hard sail 10mm thick with horizontal ribs and weighing 30 tonnes has enough strength as a main sail for propulsion in wind velocities of around 15 metres per second.
Based on a simulated voyage along an actual Pacific trade route near Hawaii, the sails could result in 64 percent less fuel use and would generate enough forward thrust to drive a 180,000DWT bulk carrier at 14 knots in winds of 13 metres per second from the beam.
Wendy Laursen