May 5, 2003
Calvin Works on NASA Project
In November 2002 researchers at the Lawrence Berkeley National Laboratory, working with scientists at Cornell University, made an unexpected discovery that could one day yield a full-spectrum solar cell.
Now two students from Calvin College will lend a hand to those solar cell efforts.
Calvin engineering professor Paulo Ribeiro (left) has received a grant of $9,000 from NASA's Jet Propulsion Laboratory (JPL) to fund two students to study the possibilities for this new solar cell technology, specifically its possible use in micro satellites that would orbit Mars.
Ribeiro (who last winter was named a Fellow in the Institute of Electrical and Electronics Engineers, a rare honor) and fellow Calvin engineering professor Matt Heun (who used to work for JPL) (right) will supervise two junior engineering students: Sam Schoofs (formerly of Dubuque, Iowa and now of Grand Rapids) and Paul Sokomba (of Jos, Nigeria).
Their project could have significant ramifications for space research.
Says Ribeiro: "The ability to convert virtually the full spectrum of sunlight into energy, with efficiencies of 50 percent or higher, could revolutionize the use of solar power for space applications."
Sokomba (top pic below) and Schoofs (bottom pic below) will work for 8-10 weeks this summer to evaluate the new technology.
Both students are excited and a little apprehensive.
Says Sokomba, who after Calvin plans to go to graduate school and then return to his native Nigeria: "I am excited about the experience this project will give me since I will be exposed to advanced technologies and have the opportunity to investigate and work with them. But I am also a little overwhelmed. I'm glad that we will not be working alone but will be working with two great professors."
Adds Schoofs: "Just being involved in a project of this magnitude is exciting. This is an area that will likely receive increasing attention from scientists and engineers in the years to come and it is good to be gaining knowledge of it now. It is intimidating to be researching for companies with such recognition as NASA and JPL. But just knowing that my work will have an influence, however small, on this project provides an extra motivation for me to work hard."
Their goals, says Ribeiro, will be to: explore the state of the art of advanced solar cells technology; evaluate technology under Mars orbital conditions; evaluate the impact for application to microsat power systems; and determine possible thermal and other operational and lifetime system issues.
Developing solar energy in a satellite orbiting Mars will provide some challenges not found on earth. For one Mars is some 120-150 million miles from the sun (depending on where it is in its orbit). In contrast the earth is about 90-95 million miles from the sun. So distance is one engineering concern. Another is radiation.
Ribeiro, who once worked for NASA on designing power for a moon station, says such considerations will be part of the students' research this summer, research that will replicate real-world conditions.
"This," he says, "is some of what they (the students) might expect to be doing once they graduate and are working as electrical engineers. They'll be doing a lot of research and reading this summer. But they are good students. They will do well."
What they'll be reading about has the potential to change space exploration and solar energy on earth.
The team at Berkeley last winter discovered that a single system of alloys incorporating indium, gallium and nitrogen can convert virtually the full spectrum of sunlight -- from the near infrared to the far ultraviolet -- to electrical current. If solar cells can be made with this alloy, they promise to be rugged, relatively inexpensive -- and the most efficient ever created. Solar cells so efficient and so relatively cheap could revolutionize the use of solar power not just in space but on earth.
Now the theory has to be put to the test. And so Ribeiro was invited to spend the summer at JPL working on this research project. Because of a busy schedule of summer conferences he was not able to commit to being in California. But he was able to convince JPL to house the project at Calvin instead, something he says he had hoped would happen when he came to Calvin in 2000 after having studied in his native Brazil, then England (where he earned a Ph.D.) and finally in the United States, where he added an MBA.