Solar car team wins 1st place in 2,500-mile stock-class race

Stefano Paltera/North American Solar Challenge Solar

The Stanford University solar car, Solstice, crosses the finish line at the University of Calgary to win first place in the stock category (and ninth overall) in the 2,500-mile North American Solar Challenge, which began in Austin, Texas, and ended in Calgary, Alberta, Canada.

The Stanford University Solar Car Racing team is the first-place winner in their class for the North American Solar Challenge. On July 26, the solar-powered car, Solstice, completed the ten-day race from Austin, Tex., to Calgary, Canada—a distance of 2,500 miles.

There were four team members who took turns driving Solstice and 11 other members who went out with them for the race. Over the course of the competition, the vehicle whizzed at up to 65 miles per hour.

"We definitely turned it around with this car," says team member Brian Cheung, a graduate student in mechanical engineering, noting that this was Stanford's first victory in the Solar Challenge.

The road to success, however, wasn't without a few bumps. At the starting line, the team encountered a circuit malfunction caused by a loose wire. "We got off about a half an hour late at the starting line, which ended up putting us about two or three hours behind," says team member Carrie Bobier, an undergraduate in mechanical engineering.

Once the team got on the road, the car ran smoothly until just hours later when the driver encountered a Texas thunderstorm. The solar car's hatch wasn't waterproof, so rain began leaking through cracks and two ventilation ducts, eventually causing water to pour onto the driver's lap and on the circuit breakers.

Team member Nick Meyer, an undergraduate, says the entire Stanford crew had to "pull over in the downpour, frantically tape over those vents and fill the cockpit with diapers that some forward-thinking team member had bought—just in case. The team ended up carving some foam plugs for the ducts in the hatch and giving the driver a few diapers to keep in the car."

Over the next week, Solstice ran smoothly, and the team managed to catch up to its competitors. Everything was going well for the car, but not quite so well for the people managing the car.

"The team got caught on the side of the road one night in Minnesota with no mosquito spray," Meyer recalls. "The total bite count that night was somewhere in the high hundreds. We also had one frigid night in Regina, Canada, and everyone was wearing every single piece of warm clothing they had packed." Some of the students forgot to bring sleeping bags, Meyer adds, and "consequently froze."

Toward the end of the race, the team ran into a problem, literally. A miscommunication between the driver of the solar car and the team's chase van resulted in the chase van rear-ending Solstice at a stoplight, damaging 54 solar cells. Team members ended up spending their day off in Medicine Hat, Canada, replacing the broken cells and repairing minor body damage.

The racers set off on the next and final day of the competition in the lead, but the team members realized that they had forgotten to turn on the parts of the solar array they had replaced. "We were only running on two-thirds of the power we had," explains team leader and engineering student Eerik Hantsoo. "It was a huge oversight on our part."

Not wanting to lose the lead, Hantsoo and his teammates kept the car rolling. One vehicle caught up to Solstice but didn't pass, thinking the Stanford team was employing some kind of strategy, Hantsoo says. But the Stanford group soon became disheartened when its main competitor, CalSol from the University of California-Berkeley, passed Solstice just 30 miles from the finish line. Then, when Stanford's chance of winning looked the most bleak, within five miles of the finish line, CalSol malfunctioned and had to pull over to the side of the road, allowing Solstice to re-gain the lead.

After a late start and a nail-biting end, the Stanford Solar Racing team made it to the finish line in 68 hours and four seconds, winning first place in its class. While some team members say they can empathize with team CalSol, they all are pleased with the car's performance and the team's determination. Cheung says, "Winning is a testament of how strong our team is."

Latice Strickland is a science-writing intern at the Stanford News Service.