A University of Delaware-led consortium has received Defense Advanced Research Projects Agency funding to double the efficiency of terrestrial solar cells within 50 months.

A broad consortium led by the University of Delaware could receive nearly $53 million in funding--with the bulk of the money coming from the Defense Advanced Research Projects Agency (DARPA)--to more than double the efficiency of terrestrial solar cells within the next 50 months.

The University's Consortium for Very High Efficiency Solar Cells, which consists of 15 universities, corporations and laboratories, could receive up to $33.6 million from DARPA, if all options are awarded, and another $19.3 million from UD and corporate team members. Those corporate members may include DuPont, BP Solar, Corning Inc., LightSpin Technologies and Blue Square Energy.

The consortium is being led by Allen Barnett, principal investigator and research professor in UD's Department of Electrical and Computer Engineering, and Christiana Honsberg, co-principal investigator and UD associate professor of electrical and computer engineering.

The award is the largest in the history of solar energy research, according to Rhone Resch, president of the Washington, D.C.-based Solar Energy Industries Association. "I applaud DARPA for recognizing the tremendous potential of solar energy to provide reliable electricity to our troops in the field and to improve our energy security here at home," Resch said.

"The University of Delaware is very excited by the support provided by DARPA and our corporate partners for this important research," UD President David P. Roselle said. "We look forward to taking a lead role in this project, which is one we believe will provide for a wholesale advance in the efficiency of solar cells."

"Solar energy inquiry has long been an important part of the University of Delaware research mission, and we are pleased to participate in this significant work," UD Provost Dan Rich said. "This project is of vital importance, given the need for alternative sources of energy."

The DARPA program calls upon the consortium to develop and produce 1,000 Very High Efficiency Solar Cell (VHESC) prototypes that are affordable and that operate at efficiencies of at least 50 percent. Currently, high-end solar cells operate at a peak efficiency of 24.7 percent, and solar cells off the production line operate at 15-20 percent efficiency.

The consortium's goal is to create solar cells that operate at about 54 percent efficiency in the laboratory and 50 percent in production, Barnett said.

The VHESC would have immediate application in the high-technology military, which increasingly relies upon a variety of electronics for individual soldiers and the equipment that supports them. As well, it is expected the solar cells will have a large number of commercial applications.

"When successfully completed, the Very High Efficiency Solar Cell technology will be a breakthrough in providing portable power to the soldier in the field," Douglas Kirkpatrick, program manager for DARPA, said.

"Solar generated electricity is a high value energy source," Barnett said. "This award provides another critical step as solar electric power moves into the commercial mainstream."

"The creation of affordable, high-efficiency solar cells is a challenge in that it presents not a single problem but a complex set of interrelated problems," Honsberg said. "We believe that with the support provided by DARPA, and with the large pool of knowledge and creativity within the consortium, we will be able to achieve that goal."

To achieve high efficiency in less than five years at low cost, Barnett and Honsberg have proposed using a new very high performance crystalline silicon solar cell platform and then adding multiple innovations. They had been working on very high efficiency solar cells long before learning of the DARPA program.

An important new feature is based on novel approaches to the integration of the optical, interconnect and solar cell design to provide for affordability and also flexibility in the choice of materials and the integration of new technologies as they are developed.

"By integrating the optical design with the solar cell design, we have entered previously unoccupied design space that leads to a new paradigm about how to make solar cells and how to use solar cells, and about what they can do," Barnett said.

A key part of the project is not just developing high efficiency solar cells but making the transition from the laboratory to production and the marketplace. Barnett said he believes the consortium will be successful because of the participation of corporations already involved in manufacturing in the field and because several team members, himself included, have experience in bringing high-technology products to market.

Honsberg said the scientific research teams will take an interdisciplinary approach, considering developments in a number of areas, including materials engineering, bio-inspired materials and self-assembly at the nanoscale.

"This project requires the consortium to invent, develop and transfer to production this breakthrough solar cell. One rarely gets an opportunity such as that," Barnett said. "Engineering is the use of science to develop products for the benefit of mankind, and this is a classic case. Furthermore, it will lead to extraordinary student experiences at all levels."

In addition to UD and the corporate members, the consortium includes the National Renewable Energy Laboratory, the University of Rochester, the Georgia Institute of Technology, Purdue University, the University of California Santa Barbara, the Massachusetts Institute of Technology, Harvard University, the University of New South Wales, Yale University and Carnegie Mellon University, all subject to successful negotiation of subcontracts with UD.

UD offers one of the nation's broadest research programs in photovoltaics. It is home to the Institute of Energy Conversion, a multidisciplinary laboratory devoted to the research and development of thin film photovoltaic solar cells, and the High Efficiency Solar Cell Program in the Department of Electrical and Computer Engineering, and is developing one of the nation's most complete courses of study for solar power systems.

Barnett earned a doctorate in electrical engineering from Carnegie-Mellon University, is a Fellow of the Institute of Electrical and Electronic Engineers (IEEE), was awarded the IEEE's William R. Cherry Award for outstanding contributions to the advancement of photovoltaic science and technology and won UD's Karl W. Böer Solar Energy Medal of Merit in 2001 for "pioneering high-performance, thin-crystalline silicon solar cells, founding and leading a world-class enterprise for the commercialization of solar electric products, and outstanding continuing service to the solar electric power community."

Honsberg earned a bachelor's degree in electrical engineering from UD in 1986, a master's degree in 1989 and a doctorate in electrical and computer engineering in 1992. She was an associate professor in the Centre for Photovoltaic Engineering at the University of New South Wales from 1993-2000 and an associate professor of electrical and computer engineering at Georgia Tech before joining the UD faculty in 2004.