As you read this, 44 teams are racing custom-built cars on a 3,000-kilometre route in Australia's Northern Territory, from Darwin in the north, to Adelaide on the country's south coast. This marathon is called the World Solar Challenge—and, yes, all the cars are powered by the sun.
The 2015 entry list features teams from every inhabited continent on the planet, including one from Canada called Blue Sky Solar Racing, made up of students from the University of Toronto. The 13th edition of the biennial race, which began this Sunday, October 18, marks Blue Sky Solar Racing's fifth entry.
Horizon, as Blue Sky Solar Racing's car is named, will drive from 8 am to 5 pm each day, with two support cars for assistance. Each evening, the teams must find a spot by the side of the highway, in the middle of the Outback, to set up camp, before waking early to recharge the car at sunrise.
They estimate it will take their car six days to reach the finish, but in previous years, teams have done it in as little as four.
"We have a 17-person team in Australia and we have three drivers," explained Nicole D'lyma, a fourth-year electrical engineering student responsible for the team's promotion and sponsorship, who will be behind the wheel for part of the race. "We rotate about every three or four hours."
In 2013, the team finished eighth in the Challenger class—which only allows cars running purely on solar energy—after racing against teams from universities, special interest groups and private industry (there is also a Cruiser class for more practical cars, which mix solar power with other energy sources).
Although the cars are incredibly advanced, the format of the race is something of a throwback. The first car races were city-to-city rallies on public roads, including the 1894 Paris-Rouen race and the infamous 1903 Paris-Madrid disaster. These races evolved into modern closed-circuit racing and professional rallying (which takes place over controlled stages).
The World Solar Challenge, however, is run on the Stuart Highway, which will not be closed to the public for the event.
The cars must follow regular traffic laws—but the limitation of how much solar energy they can collect means that, even if teams wanted to, they could not exceed the speed limit for long. The Nuon Solar Car Team from the Netherlands, for example, won the 2013 race with an average speed of 90.71 km/h.
"We make cars which basically run with the energy of a hairdryer and we run that at 100 kilometres an hour," said Tij Gupta, Blue Sky Solar Racing's mechanical lead and recent mechanical engineering graduate, who was also on the 2013 team. "It's all about taking into account things like weather conditions, road conditions, so it's not just about going as fast as you can; it's about managing your energy over the entire race."
Driving Horizon is also "quite different" from driving a regular road car, D'lyma explained. "The space, of course, is a lot smaller so it's cramped up. It's obviously lighter and more sensitive, so it just takes a bit of getting used to, but we've done a lot of testing."
According to D'lyma, all of the students involved with the team are doing it as an extracurricular activity and most of their free time is spent in the workshop. Meanwhile, they also manage full course loads and receive no academic credits for their work on the solar car (unlike some other schools, where the project counts toward a Masters degree).
While the students are completely responsible for the project, D'lyma explained, the university does provide some funding and access to workshop facilities, and professors are always willing to give advice.
"People are willing to spend a crazy amount of time on crazy ideas and you learn off each other, teach each other and it's a great environment," says Gupta. Former challengers have gone on to work for companies such a Tesla Motors—chief technical officer JB Straubel is an alumnus of Stanford University's solar car team, for example—and the founders of Nanoleaf, which claims to build some of the most efficient light bulbs in the world, are all former Blue Sky Solar Racing team members.
The team is also responsible for finding their own sponsors, which is part of D'lyma's job description.
"We do use a lot of aerospace-grade materials which are quite expensive, and to enable that, we do get a lot of the materials donated by companies," she said.
Those materials have allowed the construction of incredibly efficient vehicles, which can now traverse an entire continent powered only by the sun.
As for Blue Sky Solar Racing's goals in this year's race "Just finishing would be an accomplishment on its own," D'lyma said. "In 2013, there was about 40 teams and only 10 of them actually finished the race entirely on solar power, so that's our main goal, to finish the race fully on solar power."
"The other goal," Gupta added, "would be to be the top student-run team."