Twenty-five years ago, Karl Böer, Distinguished Professor of Physics and Solar Energy, recognized the potential of thin-film photovoltaic cells as a clean and inexpensive way of supplying energy.
With funding from the National Science Foundation and electric power utilities, Böer established UD's Institute of Energy Conversion (IEC) in 1972-long before the first oil embargo and the formation of the U.S. Department of Energy. Solar cells at that time were made of copper sulfide and cadmium sulfide with an efficiency rating of only 3 to 5 percent.
Over the past quarter century, members of UD's institute have made extensive modifications to solar cells and steadily increased their conversion efficiency. In 1973, Solar One, the first house to convert sunlight directly into both heat and electricity for domestic use, was built at the University, paving the way for the accumulation of data on a solar harvesting system.
By 1977, under the direction of newly appointed director Allen M. Barnett, the institute had developed a wholly new photovoltaic material, zinc phosphide, and had started an amorphous silicon program. T.W. Fraser Russell, Allan P. Colburn Professor of Chemical Engineering, became director in 1979, leading the institute until 1996. He remains today as chief engineer. Under his direction in 1980, the institute attracted a three-year, $750,000 contract from Chevron Research Co. to improve the process for continuous deposition of semiconductor thin-film on inexpensive metal substrates. Institute research demonstrated the feasibility of depositing a semiconductor on a continuously moving flexible web, winning three patents.
By 1980, IEC had developed the first thin-film solar cell to exceed 10 percent efficiency. Over the next few years, the institute developed tandem solar cells, and, ultimately, it became the only laboratory in the world to fabricate solar cells using four different absorbing semiconductors- amorphous silicon, cadmium tellurium, copper sulfide and copper indium diselenide.
In 1982, a new, $2.5 million laboratory was built on the UD campus to house the institute. There, three systems to make amorphous silicon solar cells were created. The institute continued to establish its reputation as a leader in the design and interpretation of experiments, providing essential information for commercial-scale production.
In 1992, IEC was recognized by the U.S. Department of Energy and the National Renewable Energy Laboratory for its efforts in thin-film photovoltaic research and education. Robert W. Birkmire, a physicist who joined IEC in 1979, became institute director, and, under his direction, the institute is providing technological support as a member of a Department of Defense consortium of five companies.
Today, IEC has established collaborative efforts with many university groups, both nationally and internationally, to further develop thin-film photovoltaics. It works cooperatively with UD's Center for Energy and Environmental Policy to study the role photovoltaics can play in residential and commercial sites. And, it continues to provide a training ground for students, along with numerous postdoctoral fellows and visiting scholars.
-Jane Kilcullen, AS '99