Jun 21 2009
A solar energy research team from Valparaiso University's College of Engineering will return to Switzerland this summer to continue testing the potential of harnessing the sun's energy for industrial applications. Valpo, a member of the Council on Undergraduate Research, has been pursuing the research project since 2006.
Led by Dr. Robert Palumbo, one of the world's leading solar energy researchers, Valpo's team of engineering students will conduct a second round of experiments with a solar reactor used for high temperature solar electrolysis at the Paul Scherrer Institute. Valpo's research program is funded by a $300,000 National Science Foundation grant, and is studying a process with the potential to make large-scale storage and transportation of the sun's energy practical.
Derek Leatzow, a mechanical engineering major from Chicago, said he and other team members spent the past year redesigning and improving the majority of the solar reactor's interior components based upon last summer's test results. The electrolytic process starts after sunlight heats a crucible inside Valpo's reactor - a cylindrical device about three-feet long - to between 1,700 and 3,000 degrees Fahrenheit. At that point, zinc oxide inside the crucible separates into oxygen and metallic zinc.
"This summer we expect to gather much more information about how efficiently our reactor makes zinc and whether we get better results if the temperature is higher or if the electrical current is increased," Leatzow said. "Ultimately, we want to show industry that high temperature solar electrolysis is feasible and whether certain materials will work better than others."
Leatzow said the improved reactor is expected to yield more zinc from the electrolytic process and also allow more precise data collection.
Leann Matthews, a junior from Fond du Lac, Wis., said that in addition to observing how the reaction changes when the temperature or electrical current is altered, the team also will experiment with different electrolytes and electrodes.
There are two major factors that Matthews says the team wants to measure during its six weeks of testing. The first is the amount of electricity that is added to the reaction compared to the amount of electricity that could be obtained from a zinc fuel cell. The second, she said, is determining the difference in how much solar energy the team puts into the reaction versus the theoretical ideal.
Valpo's research team is producing zinc in its experiments because the commonly-used metal could be used in fuel cells for the production of electricity. The process thus could be a means by which solar energy is stored as chemical energy in the form of zinc, allowing it to be transported and used at any time. The higher the temperature during electrolysis, the larger the amount of solar energy that can be substituted for the electricity needed to convert zinc oxide into metallic zinc.
Each experiment takes a full day to conduct, and the team aims to complete eight or nine experiments at Paul Scherrer Institute, one of the world's leading solar energy research facilities. Joining Leatzow and Dr. Palumbo in Switzerland are senior mechanical engineering major Jackie Kondratko and mechanical engineering major and May graduate Robert Schroeder, both of Granger. Matthews will provide support from Valpo during testing.
"While high temperature solar electrolysis is too expensive to be practical on an industrial scale right now, our research is advancing scientists' understanding of the process," Leatzow said. "Hopefully we'll reach the point where it is realistic financially, and society can also benefit from the reduced environmental impact that's gained by using solar energy rather than fossil fuels."
Leatzow, who graduated in May, said he's learned a great deal from his research experience and is considering a career in green technology.
"This project has definitely sparked my interest in alternative energies to the point that I'm considering going to graduate school to pursue that," Leatzow said.
Matthews and Kondratko, along with other engineering students, will continue working on Valpo's solar energy research during the coming year. If Valpo's research team accomplishes its experiment goals this summer, next year's work will include further development of an industrial scale model for high temperature solar electrolysis.
Matthews' career goals also include working in an alternative energy field that, like Valpo's solar energy project, could help reduce the world's reliance on fossil fuels.
"In addition to this solar energy research, I'm also really interested in the automobile industry and the potential for making more environmentally sustainable vehicles that address the problems we're seeing with global warming," Matthews said. "There's a lot more work that needs to be done in that area and I'd enjoy the opportunity to be part of that."