New Generation Of Solar Cells Promises Efficiency

Researchers around the globe are racing to develop efficient thin film solar cells. The solar cells made in Luxembourg are based on a semiconductor made of copper, indium, gallium and selenium (CIGS) and made by a process with the potential for highest performance. Furthermore, the scientists of the University of Luxembourg produced another solar cell based on a new cheaper material, which does not contain the costly indium, and made by a low cost galvanic process. This solar cell has reached an efficiency of 3.2 percent. This is already close to the world record: the worldwide best cell based on this new material and prepared by a similar low cost process shows an efficiency of 3.4 percent.

The laboratory for photovoltaics of the University of Luxembourg is a group of researchers developing new materials and processes for solar cells. Of all the available thin film technologies, solar cells based on CIGS have shown the highest efficiencies in research and in production. Prof Susanne Siebentritt, head of the laboratory, explains: "Currently we can produce the heart of the solar cells, the so called absorber layer and the buffer. But for completing the solar cells we rely on the help of our colleagues from Helmholtz-Zentrum Berlin". The luxembourgish laboratory focuses not only on the development of solar cells but also on furthering the physical understanding of the materials and interfaces involved in these solar cells.