Students from the U's solar car team load the outer shell of Borealis III onto the transport trailer bound for Texas. On top of the lightweight shell are more than 3,000 individual solar cells, smaller than a playing card and about as delicate as a potato chip.
The ra(y)ce is on
U solar car team shooting for title
By Rick Moore
Published on July 15, 2005
In terms of athleticism, this certainly isn't the Olympics. And when it comes to endurance, it doesn't quite compare to the Tour de France. But when you combine intelligence, ingenuity, preparation, and perseverance, producing a competitive car for the biennial North American Solar Challenge--and then getting to the finish line--are stellar accomplishments.
The University of Minnesota's entry, Borealis III, is expected to be among the front-runners of the 2,500-mile "rayce" for solar-powered cars that begins in Austin, Texas, on July 17 and concludes in Calgary, Alberta, on July 27. Borealis III finished first out of 18 teams in the 2005 Formula Sun race in Kansas this spring, and in car racing terms has earned the pole position, in a manner of speaking. It will be the first car to take off in the staggered start Sunday in Austin.
On July 9, the day before setting out for Texas for a week's worth of pre-race inspections, the U contingent invited the media for a glimpse of its creation at the Engineering and Fishing Laboratories Building on the St. Paul campus. Shortly after noon, the vehicle sat inside the building in two pieces while students packed and made final preparations for the upcoming odyssey. Outside, the sun beat down relentlessly--a fitting reminder of its horsepower that the U students hope to harness better than their competitors.
Borealis III updates
Check the Solar Vehicle Project Web site for daily updates on the progress of Borealis III.
But when you hear how everything fits together into a futuristic car that can travel--fueled entirely by the sun's rays, at times--at 75 mph, this quirky vehicle takes on a new beauty.
"Driver comfort isn't a big priority," says Kahly, one of the U's drivers. "It's to get the car down the road as efficiently as possible."Some 46 undergraduate students at the University have been working on assembling and refining Borealis III since January of 2004, and they've put in an estimated 43,000 hours of time in research, design, fabrication, and testing, according to the Solar Vehicle Project Web site. They were subdivided into electrical, mechanical, solar array, and aerodynamics teams that used the latest in interdisciplinary technologies. For example, the digital electronics are similar to those used in regular automobiles, and the high-efficiency solar cells are similar to those used on the Mars Rovers.
History of U solar
The U's Solar Vehicle Project was founded by a group of Institute of Technology undergraduates in 1990. The team completed Aurora I, its first car, in three years to compete in the 1993 GM Sunrayce. The project remains true to its origins as a student administered, designed, and built project that teaches members about engineering and management in a complete product-development environment.
The final product is a sleek 370-pound machine--the lightest and most powerful solar car that a U team has ever produced--and about 60 pounds of that is in batteries, which are used in conjunction with the sun. Students are hoping to parlay the design to improve a notch on the performance of Borealis II, the U's entrant that finished second in the 2003 North American Solar Challenge.
Once the race begins, it's not simply a matter of a U driver pointing the car in the right direction and waiting for the sun to do its thing. According to Mitch Hornwyffels, a 2005 mechanical engineering graduate and the mechanical team co-leader, the strategy during the race can be as important as the car's design. There are many factors to consider, he says, such as latitude and longitude (which determine the angle of the sun), topography (it can be an advantage to accelerate going down a hill and then coast going back up), and weather, which of course alters the effects of the sun. "We have to consider the weather and how much battery power we can use each day," adds Martin "Brain" Sturm, an electrical engineering major.
There is a lead van and a "chase" van accompanying the solar car, and team members in the chase van are continually monitoring data streamed to them from the car's seven student-designed circuits "to know what the car's doing at all times," says Hornwyffels. That's more support than Lance Armstrong gets.
But support doesn't always equal comfort for the drivers. Four U students have qualified to drive in the cross-countries race, and will put in shifts of up to six hours. Once they step in the car they'll face temperatures up to about 20 degrees warmer than the outside temperature. And air conditioning isn't a factory design feature of Borealis III.
"Driver comfort isn't a big priority," says Zac Kahly, a 2005 aerospace engineering grad and one of the U's drivers. "It's to get the car down the road as efficiently as possible." He says one of the requirements of the race is to bring a water bottle in the car. "You definitely feel the heat," he says. "I sweat a lot, so I'll have sweat pouring off me when I get out."
Kahly also owns the distinction of being in the driver's seat twice when the car has been pulled over by police. Apparently a stealthy-looking vehicle with no license plates, bumpers, or headlights doesn't seem road-worthy to some law enforcement officials. But rest assured, Kahly isn't likely to pick up a speeding ticket. The race also prohibits driving faster than the posted speed or 65 mph.
Commitment to renewable energy in
Borealis III is one of the University's most visible commitments to the support and use of renewable energy. The U's Initiative for Renewable Energy and the Environment (IREE) is among more than 60 sponsors of the project. IREE aims to address the urgent need to reduce our dependence on nonrenewable, fossil fuel-based energy sources and to sustain global ecosystems. It capitalizes on Minnesota's substantial biomass, wind, and solar resources, as well as the U's research expertise and ability to facilitate collaborations and policy development.
Hornwyffels figures the U's biggest challengers will be the University of Missouri-Rolla (which won the 2003 North American Solar Challenge), the University of Michigan, and the University of Waterloo in Ontario. One key, he says, is avoiding major mechanical problems. The 2003 car had a small problem with its rear suspension, which took just over an hour to fix.
He's quite certain the car will avoid the much-more-serious problem that befell it in 2004, when a latch failure sent the entire top shell of the car--solar array and all--sailing into the air. "It took off and we all watched it fly in the air--our baby--which we'd spent hours and hours working on," Hornwyffels says.