In pictures: Solar challenge race begins in Australia

Team members gather around cars as they prepare for the start of the race in Darwin, Australia. Photo: 8 October 2017ALLSPORT/Getty Images

Solar-powered cars from more than 30 countries around the world have begun a biennial 3,000km (1,865-mile) race from Darwin to Adelaide, north to south across the centre of Australia. This year marks the 30th anniversary of the competition.

Western Sydney Solar Team vehicle Unlimited 2.0 from Australia leaves the start line in Darwin. Photo: 8 October 2017ALLSPORT/Getty Images

Teams in the World Solar Challenge are made up of students who have built their vehicles with their own hands.

Team members congratulate the driver after Solveig, the car from Sweden's JUsolarteam team, passes testing in Darwin. Photo: 6 October 2017ALLSPORT/Getty Images

The competitors did some test runs before the start and then raced on Saturday to establish the final grid position.

The Punch Powertrain Solar Team vehicle "Punch Two" from Belgium leaves the start line in Darwin. Photo: 8 October 2017AFP/Getty Images

Belgium's Punch Powertrain team took the pole position, reaching an average speed of 83.4km/h.

The driver for DUSC, the car from the UK's Durham University Electric Motorsport gets the thumbs up signal to begin competing during time trials in Darwin. Photo: 7 October 2017ALLSPORT/Getty Images

The rules of the race are quite precise. "Based on the original notion that a 1000W car would complete the journey in 50 hours, solar cars are allowed a nominal 5kW hours of stored energy, which is 10% of that theoretical figure. All other energy must come from the sun or be recovered from the kinetic energy of the vehicle," the organisers say.

Blue Sky Solar Racing vehicle Polaris from Canada competes during time trials in Darwin. Photo: 7 October 2017ALLSPORT/Getty Images

Once the teams leave Darwin they must travel as far as they can each day until 17:00 "when they make camp in the desert wherever they happen to be". All teams must be fully self-sufficient.

Team members look on as Apollo VIII, the car from Taiwan's National Kaohsiung University of Applied SciencesALLSPORT/Getty Images

There are seven mandatory checkpoints along the race route.

ITU Solar Car team vehicle B.O.W. ISTANBUL from Turkey leaves the start line in Darwin. Photo: 8 October 2017ALLSPORT/Getty Images

At the checkpoints, only the most basic maintenance is allowed to correct tyre pressures and clean debris from the vehicle.

Solar cars and team members pose for a photo in Darwin. Photo: 7 October 2017ALLSPORT/Getty Images

The participating teams compete in three categories: the challenger class, the cruiser class and the non-competitive adventure class. The fastest teams are expected to reach Adelaide in South Australia on Thursday.

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