Wind power is not a new concept. Windmills have been around for centuries, and wind-powered sailboats have been around for even longer — since 3200 bce, or even earlier. The advent of engine-powered shipping relegated wind-powered boats to hobbyists, tourists and adventurers. But if the German company SkySails is right, we may soon see a return to shipping powered by the wind. The notion is straightforward: a large parasail-type kite on a tow cable can add significant power to a standard diesel engine ship when lofted to 500 meters or so in the air. How much power? SkySails claims that a cargo ship can increase speed for a given fuel consumption by at least 10%, and often more; conversely, a sail-enabled ship can run at its standard speed but cut fuel consumption by as much as one-half.
The technology is more efficient at capturing wind power than standard sails, takes up less shipboard space, and supposedly does not require additional crew. Navigational software linked to real-time weather data routes for optimal wind speed and travel time. The design has won a number of German innovation awards, but has not yet been field-tested in its full configuration (at least as far as I can tell); SkySails proposes that the design would work not just for commercial vessels, but for ships of all types.