Semprius Demonstrates Proprietary Solar Cell Reaching Efficiency Level of 43.9 Percent

Semprius, Inc., an innovator in high concentration photovoltaic (HCPV) solar modules, has manufactured the first four-junction, four-terminal stacked solar cell using its proprietary micro transfer printing process.

In this effort, Semprius worked in collaboration with Professor John Rogers and his team at the Frederick Seitz Materials Research Laboratory at the University of Illinois at Urbana-Champaign and researchers at Solar Junction, a leading III-V high-efficiency solar cell manufacturer and important Semprius partner. The results of this project will be published this week in the journal Nature Materials.

The new stacked solar cell is comprised of a three-junction microcell that is stacked on top of a single-junction germanium microcell using Semprius’ high-speed micro transfer printing process, which enables the simultaneous formation of thousands of stacked microcells with very high yields.

By using four junctions, the stacked cell is able to capture light across a broader portion of the solar spectrum and therefore achieve efficiencies much higher than conventional silicon and thin-film single-junction solar cells. Initial trials yielded solar cells with measured efficiencies up to 43.9%. This process is capable of achieving solar cell efficiencies greater than 50% in the near future.

“We would like to thank our collaborators at the University of Illinois and Solar Junction for their help in this project,” said Scott Burroughs, vice president of technology at Semprius. “Because the process we used is fully compatible with our current production processes, we believe this demonstration can be easily transferred to manufacturing.”