CPV Intelligence Brief 29 April – 13 May 2014

Semprius demonstrates 4 junction cell stack

Semprius, a developer of high concentration photovoltaic (HCPV) solar modules, has manufactured the first four-junction, four terminal stacked solar cell using its proprietary micro transfer printing process, the company has reported.

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 cell manufacturer Solar Junction.

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

The four junction stack can capture light across a broader portion of the solar spectrum, achieving efficiencies higher than conventional silicon and thin film junction solar cells.

Initial trials yielded solar cells with measured efficiencies up to 43.9%.

The process is capable of achieving solar cell efficiencies greater than 50% in the near future, according to Semprius estimations.