The most complex solar-powered machine most people come across is probably a calculator. But that didn’t stop a group of engineering undergrads from aiming higher when it comes to the potential power of the sun. They built and raced solar-powered boats in the annual Solar Splash competition, held this year 18 to 22 June at Lake Fayetteville on the campus of the University of Arkansas. The contest attracted 18 teams of students from 16 universities in Canada, Turkey, and the United States.
The solar/electric boat race determines which undergraduate team can build the fastest, most innovative boats, many of which top 10 meters per second.
“The purpose of the competition is to teach students about renewable sources of energy,” says IEEE Member Roy McCann, organizer of the event and associate professor in Arkansas’s electrical engineering department.
SOLAR SPLASH Each team, led by a faculty advisor, built a boat up to 6 meters long that competed in a variety of events, including a 300-meter sprint, a four-hour endurance race (the average boat can travel 40 kilometers in that time), and a slalom race. Each team also had to write a technical paper explaining the details of its boat’s operation and to create a visual display targeted toward a general audience. Scores from each of these components were tallied to determine an overall winner.
This year’s first place team, from Cedarville University, in Ohio, finished the 300-meter race in just 26.5 seconds. The team received a trophy, which is passed on each year to the next winner. Host Arkansas placed second, and Istanbul Technical University, in Turkey, finished third. Each received certificates and smaller trophies.
The boats were scored on design innovation and the ability to maneuver through the water. Materials needed to build the boats cost between US $8 000 and $30 000, all paid for by each teams’ own fundraising efforts.
The boats had to operate reliably under vibration of the motor and in the presence of moisture. “That knowledge can be applied not to just boats but also to planes and cars,” McCann says. “The students will be able to put what they learned here into practice in their careers.”
Boat designs varied from two-hull catamarans to one-hull speedboats. They were built of wood, fiberglass, carbon fiber, or other materials. “Most teams made their own hull, but some were able to order it preassembled,” McCann says. “The same goes for solar panels; some students bought them already in an array, others opted to buy separate solar cells and connected them together.”
Most designs sported a power setup that included a solar panel–and–battery system connected to an electric motor drive, which in turn fed a dc motor that powered the boat. Of course, all had to rely on solar power.
But the hard work didn’t end when the team finished building its boat. “Much depends on the skill of the boat captain almost as much as the boat itself,” McCann says. “You need someone who can maneuver and control the boat, and you need a boat that can overtake the others in a race.”
SMALLER SOLAR BOATS In addition, with the help of a $3000 grant from the IEEE Foundation, the Fayetteville Public Library and the University of Arkansas organized the Solar Bug Tug workshop earlier in June at the library. The event allowed preuniversity students to build their own, albeit smaller and remote-controlled, solar-powered watercraft with the help of UA electrical engineering students.
“The event is a way to get local students interested in electrical engineering and so that one day they can even compete in the Solar Splash,” McCann says. “It’s a combination of outreach and education.”