VIDEO: World's biggest solar car race underway

Over forty solar-powered cars have set out on the 3,000km journey from Darwin to Adelaide in the biggest solar car race in the world.

47 cars will face the challenge of going the 3,000km with no source of power other than the sun.

The race was first held in 1987 and is based on the idea that a 1000 watt car can complete the trip in just 50 hours.