The World Solar Challenge has kicked off for another year, with Holland's Nuon Solar Team taking an early lead. The challenge has competing teams from all over the world race solar-powered vehicles thousands of kilometers across the Australian Outback and defending champion Nuon is looking to claim its seventh title.

The World Solar Challenge is an endurance race designed to inspire innovations in solar power by having teams design and build vehicles that are powered only by the sun, before racing them from Darwin in northern Australia to Adelaide in the south, some 3,000 km (1,864 mi) away.

As it celebrates its 30th anniversary, the World Solar Challenge boasts its largest field ever, with 50 entries hailing from 26 different countries. Thirty-one of those are taking part in Challenger Class, the main event, which Nuon has excelled at since 2001 taking out all but two of the titles.

And team Nuon was fast out of the blocks again this year, taking an eight minute lead over the first leg from Japan's Team Tokai and the Western Sydney Solar Team behind them in third. This is the eighth time Nuon's Nuna9 solar car has competed in the race, and most recently beat out Dutch compatriot Solar Team Twente by just ten minutes to claim the 2015 Challenger Class title.

While the Challenger Class focuses on speed, the Cruiser Class places an emphasis on energy management and passengers carried. Then there is the Adventure Class, which is non-competitive and allows cars built for previous events to run again, typically with new team members on board. The idea behind all of this is to drive solar energy forward and not just inspire highly efficient electric cars, but develop technologies that can be readily commercialized.

"Of course, the point of this Challenge is not just to go fast, or to develop technology that will never reach the mainstream," says event director Chris Selwood. "Our founder, Hans Tholstrup, our faculty, and competitors past and present, are all determined to make sustainable, energy positive, solar electric cars and renewable technology a reality."

The teams will make a number of stops as they race from Australia's top to bottom, and are expected to start rolling into Adelaide early on Thursday.

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