Sweden's new car carrier is the world's largest wind-powered vessel 

Oceanbird a ship that just looks like from the future, but it harks back to ancient maritime history -- because it's powered by the wind.

The transatlantic car carrier is being designed by Wallenius Marine, a Swedish shipbuilder, with support from the Swedish government and several research institutions, reports CNN.

With capacity for 7,000 vehicles, the 650 foot-long vessel is a similar size to conventional car carriers, but it will look radically different. The ship's hull is topped by five telescopic "wing sails," each 260 feet tall. Capable of rotating 360 degrees without touching each other, the sails can be retracted to 195 feet in order to clear bridges or withstand rough weather. 

The sails, which will be made of steel and composite materials, need to be this size to generate enough propulsive power for the 35,000-ton ship.

Although "the general principles of solid wing sails is not new," designing the Oceanbird's sails has been a challenge, says Mikael Razola, a naval architect and research project manager for Oceanbird at Wallenius Marine.

That's because these are the tallest ship sails that have ever been constructed. "This ship, at the top of the mast, will be more than 100 meters (328 feet) above the water surface," says Razola. "When you move up into the sky that much, wind direction and velocity change quite a lot."

To better understand the atmospheric conditions at this height, Wallenius mounted sensors on top of its existing vessels, while they were crossing the Atlantic, and gathered data on wind velocity and veer (a clockwise change in wind direction), up to 650 feet above sea level. "All of this information has helped us design an efficient wing and hull system, that can make the most of the power available in the wind," says Razola.