Once every three years, teams from countries across the world come together in Australia to compete in the World Solar Challenge, a grueling 3,000-kilometer (1864-mile) race from the North end of Australia in Darwin to the South end in Adelaide.

This year, at least two teams from the U.S., one from the University of Michigan and another from the Massachusetts Institute of Technology (MIT), will compete in the race, which starts on Oct. 16 and ends on Oct. 23.

Not all the teams have announced their entrance yet, said World Solar Challenge Event Director Chris Selwood.

“Entries are still open to the end of May. Traditionally we do not announce the full list of teams until after close of entries,” he said. Teams have until June 5 to enter. “Some teams like to keep it secret; others like to shout about it.”

The cars are getting lighter and faster, thanks to advanced materials and more powerful photovoltaic arrays.

For instance, MIT’s entrance named Chopper del Sol could reach speeds in excess of 100 miles per hour. But during the race, Chopper del Sol should be moving at the respectable clip of 50 to 60 miles per hour, according to said George Hansel, an MIT Physics student and member of the Solar Electric Vehicle team.

The vehicle’s average power consumption will closely match power produced by the array, he said.

“The top speed outright is circa 122 miles per hour,” Handel said. “We do not expect to ever drive the car that fast under any circumstances, testing or otherwise.”

That top speed is thanks to the car’s 6 square meter 1.3 kilowatt array and a lithium-ion battery system with about 6 kilowatt hours of storage.

Still, MIT will face some stiff competition.

The University of Michigan, which placed third in the last World Solar Challenge and won the American Solar Challenge last year, told The New York Times that its newest solar powered car, Quantum, weighs about 320 pounds. Its previous car was roughly 500 pounds. The university did not respond to requests for comment.

Then there’s the international competition. A U.S. team hasn’t won the competition since 1999. From 2001 to 2007, a team from the Netherlands has won the race. And in 2009, a Japanese team from Tokai University won.

Image courtesy of MIT of Chopper del Sol in development.