In pictures: Solar challenge race begins in AustraliaPublished8 October 2017Shareclose panelShare pageCopy linkAbout sharingImage source, ALLSPORT/Getty ImagesImage caption, 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.Image source, ALLSPORT/Getty ImagesImage caption, Teams in the World Solar Challenge are made up of students who have built their vehicles with their own hands.Image source, ALLSPORT/Getty ImagesImage caption, The competitors did some test runs before the start and then raced on Saturday to establish the final grid position.Image source, AFP/Getty ImagesImage caption, Belgium's Punch Powertrain team took the pole position, reaching an average speed of 83.4km/h.Image source, ALLSPORT/Getty ImagesImage caption, 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.Image source, ALLSPORT/Getty ImagesImage caption, 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.Image source, ALLSPORT/Getty ImagesImage caption, There are seven mandatory checkpoints along the race route.Image source, ALLSPORT/Getty ImagesImage caption, At the checkpoints, only the most basic maintenance is allowed to correct tyre pressures and clean debris from the vehicle.Image source, ALLSPORT/Getty ImagesImage caption, 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.More on this storyBritish solar car crashes before racePublished6 October 2017