Solar Sailor , an Australian company, has signed a deal with the largest Chinese shipping line COSCO to fit their tankers with large solar-powered sails.

The sails are 30 meters long, covered with solar PV panels that will provide 5 percent of the ships’ electricity and will harness enough wind to reduce fuel costs by 20 to 40 percent. The sails are controlled by a computer that angles them for maximum wind and solar efficiency and the company claims that the sails will pay for themselves within four years.

The shipping and air travel industries have been the hardest to conform to new efficiency demands. Planes and tankers require a lot of fuel, but our global economy depends on both of them to survive, so they’ve been hard industries to regulate. Even the latest environmental standards set by the EU included passes for shipping and airline companies.

via Treehugger