More than 40 teams from 21 countries have started their gruelling 3000 kilometre journey from Darwin to Adelaide, in the World Solar Challenge.
The smallest car competing, Solar Team Twente arrived at the first control stop of Katherine at 12.08pm on Sunday, several minutes ahead of compatriots Top Dutch Solar Racing.
In third place is Belgian team Agoria, which arrived at 12.17pm.
Event Director Chris Selwood said the challenge is more relevant today than it was 32 years ago.
"As the world debates climate change and looks to find solutions to more sustainable mobility, these incredible young people are innovating and collaborating towards a better world," he said.
Top Dutch Solar Racing's "Green Lightning" car started in pole position when it was flagged off at 8.30am on Sunday, but is now in second.
The first-time Challenger Class team from the Netherlands set a record time in qualifying at the Hidden Valley race circuit on Saturday.
At 1 minute and 51.99 seconds, it was two seconds faster than the previous best.
Defending champions and race favourites Vattenfall arrived in fifth place, despite having to pull over after a cable came loose, while Japan's Kogakuin University pulled into Katherine in fourth.
Adelaide University's reworked car "Lumen II Mark II" started the race safely in 13th position.
Mr Selwood said Top Dutch Solar Racing had been rewarded for their exceptional teamwork and attention to detail.
'The team have clearly been diligent in their preparation and I expect to see them in the mix of this hotly contested field, with any number of teams capable of crossing the finish first in Adelaide," he said.
The World Solar Challenge has been held biannually since 1987, promoting sustainability and providing a boost for the NT and SA economies.
"We're very proud to be able to host the start of this outback adventure and have been welcoming prestigious university teams from around the world..." NT Sports Minister Lauren Moss said, speaking from the start line.
As they make their way to Adelaide, teams with pass through checkpoints at Katherine, Daly Waters, Tennant Creek, Barrow Creek, Alice Springs, Kulgera, Coober Pedy, Glendambo and Port Augusta.