Students' Solar Oven Converts Plastic Trash into Roofing Materials for Resource-Starved Haitians

Wednesday, August 05, 2015
Student group with their solar oven.

Shining Example: Students in this summer's Grand Challenges for Engineering course designed a solar-powered oven that converts plastic trash into roofing shingles. (Photo by Bryan Cantwell)

At first glance, the big solar-powered oven resembles the mammoth-sized rack of ribs that caused Fred Flinstone's car to tip over in the closing credits of the old Hanna-Barbera cartoon.

Its curved surface is bowed away from the sun, creating a shiny, reflective bowl concentrating solar energy onto a single, metal tube running through its center. The heat, reaching more than 360 degrees Fahrenheit at peak times on a sunny day, melts thin plastic refuse into a liquid that can be molded into shingles for construction projects in Haiti, a country in dire need of building products and creative ideas. "It does the job, that's for sure," says Steven Lawton, a junior mechanical engineering major from Landenberg, Pennsylvania, and one of six students who spent this summer designing and building the massive oven.

The students were part of a Grand Challenges course assigned to address one of 14 global "grand challenges" identified by the National Academy of Engineering, such as making solar energy economical, providing access to clean water, preventing nuclear terror, and engineering better medicines. This is the third summer for the course, and this year's project refines a solar oven device created last summer by students.

(Video by Steven R. Lawton)

Grand Challenge students chose to work on a solar energy project to help people in Haiti, the poorest country in the western hemisphere. Haiti has few resources for building materials, but has plenty of plastic trash lying around, the students say. The new, improved solar oven converts that trash into waterproof shingles using nothing but the sun's rays and a little labor. The students designed the oven so that one person can operate it.

"We're really looking forward to seeing how this is received" in Haiti, says Leigh Mathews, a graduate engineering student from Melbourne, Australia.

Last year's oven was much taller and used cooking oil to help melt the plastic, leaving the final molded products slippery. This year's design is more compact, easier to maneuver (to follow the sun's path), and keeps the plastic dry.

But even this year's design went through a few big revisions. The first design used aluminum sheeting and plastic piping. But the aluminum didn't reflect as well as hoped (they ended up using Mylar) and the plastic pipes didn't create a strong enough frame. The final version has a sturdy wooden frame that can be easily rolled around on wheels, and will not blow away in a gust of wind. (Haiti experiences several powerful storms annually.)

Interview Cooker

Hot topic: Students explained their solar oven design concept to local media and campus guests during a product demonstration in the Branam Innovation Center. The session was a requirement of this summer's Grand Challenges for Engineering course, which combines principles of engineering, physics, and English. (Photo by Bryan Cantwell)

Also this year, Rose-Hulman has partnered with students from Clemson University's Clemson Engineers for Developing Countries organization to test the oven in Haiti this fall and then report their findings. The oven was designed to be easily assembled and disassembled for shipment to Haiti.

The students' goal was to improve living conditions for some of the world's poorest people. If that happens, their summer of long days designing their oven and sweating in the hot sun outside the Branam Innovation Center will have been a success.

"The people of Haiti haven't even recovered from the [deadly 2010] earthquake," says Lawton, recalling the natural disaster that took the lives of 200,000 people. "Being able to change some of that is just phenomenal," he adds.

Other students working on the project included Jared Falk, a sophomore mechanical engineering student from Indianapolis; Stephen Housman, a senior chemical engineering student from Elkhart, Indiana; Chris Schenck, a junior mechanical engineering student from Terre Haute; and Dimitris Valioulis, a senior civil engineering student from Thessaloniki, Greece.

The Grand Challenges course was taught by Assistant Professor of Physics Scott Kirkpatrick, PhD, English Professor Anneliese Watt, PhD, and Assistant Professor of Mechanical Engineering Ashley Bernal, PhD.