Windpower is a pretty poor source of energy (at least over most of the Earth’s surface and in the absence of a government subsidy). It does, however, provide an effective way to distribute goods around by sea. Now the use of sailing ships is being widely revisited for this purpose.
Conventional sails require to be hoisted and lowered in order to maximise propulsion, and avoid damaging the ship to which they are attached. This is a laborious process, even if the hoisting is undertaken mechanically.
Today’s invention is a set of fixed sails on a large sailing transport ship. The sails stay in position, irrespective of wind condition. Each of these has a series of long, linear cuts made in it. The cuts can be opened or closed using large, robust zip fasteners.
These zips can be driven by computer-controlled winches to different positions in order to tune the drag of the sails and optimise their response to the wind.
