We've been taking a closer look at some of the standout blue-sky concepts presented by the likes of Mercedes and Cadillac at the recent LA Design Challenge – here's Volvo's take on the lightweight car of the future. The clamshell-inspired Volvo Air Motion Concept Canyon Carver uses fewer and lighter components than in traditional cars and compressed air engines to achieve a weight estimated at under 1000 lbs (454 kg).

Much of the weight saving would come from using compressed air motors rather than a heavy internal combustion engine along with a carbon fiber body. The chassis, interior and suspension design have also been simplified to further keep the vehicle light.

Volvo designers say that the need for cooling systems is removed because these air motors would cool down under load rather than heating up.

The intriguing refueling concept is also blue-sky – literally. "Air Replenishment Sites" powered by floating air turbines floating would be used to turn wind power into electricity to provide the compression.

Volvo's vision: “Imagine a vehicle lighter than a Formula 1 racing car, experiencing the adrenaline rush of carving through the canyons with up to three friends not using a drop of gasoline.”

The company unveiled a quarter scale model of the Air Motion Concept at last month's LA Auto Show.

LA Design Challenge