Empowered by the Sun

by judy woodward
photos by Brad stauffer

IT WAS A DARK HOUR for Adam Shea, a junior majoring in electrical engineering. The Solar Vehicle Project was in jeopardy. For nearly two decades, the project had given dedicated teams of engineering and science undergraduates an opportunity to design, build, and race across North American in a James Bond-style fantasy vehicle. Resembling a moderate-sized, scaly airplaine wing, the vehicle is powered on the amount of energy it takes to fuel a couple of hair dryers. For Shea and nearly three dozen teammates, the project, which culminates in the North American Solar Challenge Rayce, was to be the crown of their undergraduate career.

Members of the aerodynamics team examine the design of the shell and fairings of the solar vehicle. Students who work on the Solar Vehicle Project are divided into four groups based on major vehicle systems—aerodynamics, solar array, electrical, and mechanical.

“It’s a lot of work, but it’s the most fun, and it’s the biggest project undergraduates can get into,” explains Shea.

Then without warning, government support for the project was withdrawn last year. A year earlier, the University team had placed second in the race—by only 11 minutes—behind the national champions. Was it now to be shut out of all hope for the winner’s circle? Looking back on those tumultuous days, Shea reflects—only partly in jest—“When I thought the solar
car was doomed, I didn’t know what I was going to do with my life.”

Solar vehicle returns and more

Happily for the long-range life plans of Shea and his fellow students, help was at hand. At the eleventh hour, the Toyota Corporation stepped forward to support the competition. The University was back in the Rayce!

The team’s self-reported “lonely weekends and evenings” were once more filled. Project manager Sam Lenius, a senior majoring in electrical engineering, jokes about how he announced the revival to the group. “What are you doing this weekend? Nothing? Not nothing! Solar car is back!”

Not only is the solar car back, this year it will be joined by a solar house. In a separate development, the University of Minnesota has been chosen as one of 20 teams out of a field of more than 500 colleges and universities to compete in the Solar Decathlon, a four-year-old contest sponsored by the U.S. Department of Energy.

Ryan Maclachlan and Saul Phillips (foreground), both majoring in mechanical engineering, are working on the array of solar panels (shown below) that will be affixed to the exterior of the solar car. The University of Minnesota is one of the few collegiate teams that research, test, string, encapsulate, and assemble its entire solar array in-house.

The goal is to design, build, and operate an energy- efficient, solar-powered house, which will eventually be displayed on the National Mall in Washington, D.C., and judged in 10 categories. The University of Minnesota is the first and only Minnesota team to participate in this competition.

“Competitions like these are an important way to train the next generation of renewable energy experts,” said Dick Hemmingsen, director of the Initiative for Renewable Energy and the Environment. He stresses the benefit to the University of involving undergraduates in such complex, multi-faceted projects.

“Students are the engines that drive many of the University’s renewable energy research labs…starting out with projects such as these will allow them to become even more valuable contributors during the later stages of their academic careers,” he said.

Working on a project like the solar car, said Jacob Hanna, a senior majoring in mechanical engineering, “is a whole lot of fun,” but it’s also serious business at a University that’s known for the excellence of its solar energy research.

Tackling tough problem-solving

The undergraduates meeting in an empty classroom in Akerman Hall one cold February evening probably don’t think of themselves as anything so portentous as ‘valuable contributors.’ That’s only because they are absorbed in the sheer awesome coolness
of their project. Their current vehicle, Centaurus, is still in production in a St. Paul campus shop, but they are happy to show off the previous prize-winning model, Borealis III.

Konrad Brown, a junior majoring in aerospace engineering, is the primary designer of the aerodynamic shape of this year’s solar vehicle, Centaurus I. Here he tests a plywood mock-up of the vehicle’s driver’s seat and inside framework to ensure the driver can get in and out safely while clearing the bulk heads and roll bars.

Centaurus, they explain, will have design modifications that should make it more comfortable for the driver. For one thing, the driver will be able to sit up. With its tiny ventilation slits and narrow, recumbent driver’s space, Borealis III could reach interior temperatures of 135 degrees. However, comfort and interior luxury are not the point. This is a racing car, designed to go the distance under power generated entirely by the array of solar cells delicately fixed to its exterior.

“The trick is to regulate the speed to maximize the benefits of the available sunlight,” explains Lenius. A cloudy day in Minnesota is going to provide less charge than the glaring sun of the Texas plains, and the savvy team must know how to deal with both. Otherwise, the vehicle might face the ultimate humiliation— a dead battery in the middle of the race.

Weather forecasting is only one of the skills team members must master. Students are divided into four subgroups: aerodynamics, electrical design, mechanical systems and, of course, the design and fabrication of the all-important solar array.

Participants acquire some interesting insights into the educational value of the Solar Vehicle Project. “The interdisciplinary integrations,” are what Hanna calls the most useful part of the project. “Learning to organize a group of people and manage a timeline.”

For Emily Johnston, a senior majoring in electrical engineering, it’s the team effort. “It’s really cool to be part of a process,” she said, “I enjoy problem solving in groups.”

Watching “power flow” the first time he tested solar cells delighted Ryan Maclachlan, a junior majoring in mechanical engineering, but he was surprised by something else. “The scope of interactions with people,” he said. “It doesn’t seem that there should be that much talk—but there is.”

The U of M’s solar vehicle, Borealis I, placed second in the 2005 North American Solar Challenge Rayce, 11 minutes behind the University of Michigan. This summer, the 2008 race begins in Dallas, Texas and ends 10 days later in Calgary, Alberta.

For project manager Sam Lenius, working on the Solar Vehicle Project has given him an unexpected benefit. Not only has he has improved his technical savvy but his social skills. “I used to be introverted and awkward,” he said in mock humility. Then he squares his shoulders and, to the obvious enjoyment of his fellow students, transforms himself into a parody of a polished young professional as he intones, “My leadership experience in the solar car project has greatly improved my social skills and ability to lead people.”

The team also has the never-failing pleasure of watching the reactions of bystanders when they take their odd-looking vehicle out in public. They can draw a crowd in minutes, but the gold standard, said Nick Simon, a junior majoring in aerospace engineering, is seeing “how many kids fall off their skateboards.”

Jeff Hammer, an instructor in the Department of Aerospace Engineering and Mechanics, became the faculty advisor for the Solar Vehicle Project this year after long-time advisor Patrick Starr, a professor of mechanical engineering, retired. “It’s amazing to see how the students mature when they assume the responsibilities that go with the project. They beat down my door wanting to learn. It’s wonderful to teach under those conditions,” Hammer said.

When it rains, it pours

When it looked as though the Solar Vehicle Project may not go forward, a proposal was submitted to participate in the 2009 Solar Decathlon. In January, the University learned it had been selected to compete in the prestigious international contest.

Beauty and efficiency were integrated in the house created by Technishe Universitat Darmstadt in Germany. Named overall winner of the 2007 Solar Decathlon, the team used oak louvers in their solar-powered home to provide shading and privacy. Darmstadt was one of seven teams to score a perfect 100 points in the Energy Balance contest, which required teams to use only the energy generated by the solar electric systems during the competition

“It’s just huge,” said Ann Johnson, the decathlon team faculty advisor and director of the University’s construction management program. “It’s one of the largest multi-disciplinary projects the U has ever done.”

Led by the Institute of Technology and the College of Design, both undergraduate and graduate students from a host of disciplines ranging from mechanical engineering and journalism to financial management will be needed to construct a 700- to 800-square-foot totally solar-powered house, which will be part of an international Solar Village display in Washington, D.C.

Plans call for project participants to start gathering building materials this fall, with construction to begin spring 2009. Project organizers hope to showcase the completed solar house on the University’s Northrop Mall before disassembling it for its journey to Washington in late summer 2009.

In addition to funding received from the University and the U.S. Department of Energy, the $1 million project will require additional private monetary support and donations of in-kind materials.

Nearly 125 University students have expressed interest in working on the solar house, including an entire art class that showed up at the kick-off meeting with plans to decorate the interior. Johnson said another group would study real-world issues including marketability and the cost to mass produce the solar house. Plans also include a Next Use group that will focus on what to do with the house after its Washington sojourn. Some have suggested the house be placed permanently somewhere on campus or the Minnesota State Fairgrounds.

“One thing is clear,” said Johnson. “Students want to make sure the house is used afterwards.”

For Steve Peichel, a senior majoring in electrical engineering, the project is already changing the way he thinks about the future. “When I did physics, I was thinking communications and fiber optics were the future. But as I read more about global warming, I think this will be the issue of my lifetime,” Peichel said, who holds an undergraduate degree in physics. He also has begun to appreciate the importance of teamwork.

An estimated 120,000 visitors toured the solar-powered homes on the National Mall in Washington, D.C. during the 2007 Solar Decathlon. The University of Minnesota will be one of only 20 international teams displaying a home in the 2009 competition.

“You start, and you think you’ll find a ‘silver bullet’ technology, but it’s surprising how integrated the solution has to be, how many variables there are,” he said.

Jodi Thomas, a senior in electrical engineering, agrees. “The best thing about the decathlon is ‘discipline integration.’ As an engineering student, I have the chance to work side-by-side with students, faculty and staff members from the various colleges within the University,” she said.
Mechanical engineering professor Jane Davidson calls the Solar Decathlon an “amazing project for students.”

“The challenge is to make the building both elegant and technologically effective, so that visitors won’t say ‘there’s a solar collector,’ but ‘there is a beautiful house,’” she explained.