The China Merchant Energy Shipping company (CMES) has taken delivery of a new supertanker, whose four large sails will cut down average fuel consumption by nearly 10%.Sails, however, are very well understood, and for at least 10 years we've been seeing concepts and plans to bring large airfoils back to the cargo and passenger shipping industries.An "Aerofoil Sails Intelligent Control" system is designed to constantly monitor the prevailing conditions, as well as navigation data, and continually adjust the angle of the sails to make maximal use of available wind.The New Aden is a crude oil supertanker, so for all its promise as a testbed for green technology, its primary purpose is still to ferry somewhere around two million barrels of heavily polluting fossil fuel around the world.No mention of the additional costs vs traditional ship in building however it must make sense as the life of these vessels i think is about 3 decades?"