SYDNEY - Twenty-two bug-shaped solar cars designed and built by corporations and universities from around the world set out across the vast, inhospitable Australian outback on Sunday in the eighth World Solar Challenge.

Japan's Sky Ace Tiga car, from the Ashiya University in Osaka, led off after qualifying fastest for the 3,000 km (1,860 miles) race across the center of Australia from the tropical north city of Darwin to Adelaide in South Australia. Race leaders were expected to reach Adelaide by mid-week.

The race was devised as a challenge to design and build solar-powered cars using the most innovative application of alternative energy and transport technologies.