Penumbra is the fourteenth vehicle designed by the team, but the first cruiser class vehicle – meaning it has more than one seat. It seats four people, includes a deluxe infotainment system, and it even comes tricked out with cup holders. And there’s room for your groceries.
“It was designed with a consumer in mind,” says Matthew. “The previous versions were zippy one-seaters and looked more like space ships.” Now, the car looks like a car, and the team can actually give people rides.
Dillon Waugh, his teammate and fellow engineering student, says they took the car on a three-week tour of Iowa and visited all 99 counties, giving out rides all along their route. They even visited 3M in Minnesota to say “thank you” for donating products.
Team PrISUm started working on its first cruiser class vehicle more than two years ago. The students wanted to create something different from their previous 13 vehicles. And, something that people could picture themselves actually driving one day.
When building any solar car, especially a full-size car, they knew keeping it as light as possible would be very important. According to Matt, “We need to use advanced lightweight materials. We used 3M adhesives to help keep it much lighter.”
“Weight is efficiency,” says Dillon. “It’s hugely important. If we can save weight with carbon fiber bodies and lighter fillers, we can make it more appealing with a nicer interior. We can add speakers.”
Their time spent designing, building and testing the car culminated in an 1800-mile race across the outback. In October 2017, the PrISm racing team and their car flew to Australia. There was a bit of a shake-up during the flight and some of the electronics in the car came loose. The team worked four days – and four sleepless nights – and got the car ready to drive across the country. Penumbra battled dust, heat, clouds and rain as it traveled from Darwin in Northern Australia to Adelaide in Southern Australia. The students encountered some unexpected challenges along the way, but made it across the finish line at 1:25 p.m. on the final day of racing.
The students have become experts. Solar cars use energy from the sun and convert it to electricity. The electricity typically fuels a battery that then runs to the motor.
The sun’s energy is converted using photovoltaic cells – components inside the solar panels that were first used in space to power satellites. These cells are made up of semiconductors that absorb the light and create a flow of electrons. This flow generates electricity that powers the battery.
Solar cars combined with another power source may soon be available for sale in some countries. A maker of solar panels, announced plans to build solar vehicles and showed off four prototypes which have yet to hit the market. A French car maker created a prototype in 2006 combining solar, wind and battery power, but its speed topped out at 30 miles per hour. In a second version of the car, solar panels were dropped.
Realistically, in the near future, solar will probably play only a small role in powering the vehicle. Several car companies have created hybrid concept cars that use solar power to charge the battery or accessories in the car including lights, cooling systems and audio systems. Energy companies are also producing solutions to power electric cars with charging stations that draw their power from rooftop solar panels.
Dillon and his team at PrISUm hope the work they are doing with 3M will help to further lightweight technology development.
“The next step is to make it more practical for the daily consumer,” says Dillon. “Solar cars are expensive to manufacture and need more lightweight components. Hopefully we can work with 3M and contribute to new technology, and in the next 20 years we’ll see advancements in manufacturing and lightweight materials.”