The world's foremost solar car race has begun, with vehicles taking off from Darwin and headed for Adelaide 3,000 kilometres away.

Cars in Darwin, led by the Netherlands Team Eidenhoven's vehicle called Stella Lux, took off from the Northern Territory Parliament to cheers from a large crowd that had gathered and drove through the city towards the Stuart Highway.

There are 46 cars from 25 countries participating in the 2015 World Solar Challenge, the world's most prestigious solar car race, which began in 1987 and is now held every two years.

The Iranian car, Persian Gazelle III, got one of the biggest cheers when it left the start — but it soon had a flat tyre, only a few kilometres from the beginning of the race.

Likewise the Japanese vehicle, K.I.T Golden Eagle 5.1, broke down soon after the race began.

But it is not only sleek university cars taking part in the race.

Liberty Solar Car team from Texas is made up of high school students.

"We got our car up to 51kph [kilometres per hour] yesterday, we're hoping to get a little faster today," said Liberty's Cameron Mutis ahead of the start.

Bianca Koppen from Team Nuon, the defending champions, said she was not too concerned that her team was not starting in pole position.

Two years ago we started on place 20 and we came first... so no, it doesn't affect us I think," she said.

"We've worked for this for I think 14 months so D-Day is today so it's very, very exciting."