Tiny photovoltaic elements achieve high levels of efficiency

The use of photovoltaics - the transformation of sunlight into electric current - is well underway in Germany. The branch is booming, with growth rates of over 30%. Almost 90% of current solar cells use silicon as a semiconductor,
however a record set with another material has recently attracted attention: researchers from the Fraunhofer Institute for Solar Energy Systems ISE (Institut fur Solare Energiesysteme) have developed a solar cell from III-V semiconductors with which they have achieved a record level of efficiency in Europe of 35%. The element is only 0,031 cm2 and is composed of material from the third and fifth columns of the periodic classification.

To achieve efficiency levels of over 30%, solar cells of different materials must be stacked. "Our record cell is a triple monolithic solar cell," explains Mr Andreas Bett, project manager at Fraunhofer ISE. "She is made of
Gallium Indium Phosphide, Gallium Arsenide and Germanium (GaInP / GaAs / Ge) and is manufactured in one process. The use of three different materials increases the efficiency of the cell, the different parts of the solar spectrum are transformed in a way
optimum in electrical energy ". This type of cell, and in particular its high degree of efficiency, is of paramount importance for space research. RWE Space Solar Power in Heilbronn already manufactures cells of this type - on surfaces Much more
important - from a process developed by the Fraunhofer ISE Institute. The solar cell also has terrestrial applications. “We put the tiny cells in FLATCON (TM) concentrator modules,” explains Gerhard Willeke, director of the solar cells department at the ISE institute. "Thanks to this technology, we can obtain photovoltaic systems with efficiency levels above 25%".

Read also:  What do you think of the current hype about the environment and more specifically the greenhouse effect and energy?

First demonstrations of the FLATCON (TM) modules as well as the new cells are currently being developed at Fraunhofer ISE as part of a research project of the Federal Ministry of the Environment (BMU).

contacts:
- Dr. Andreas Bett, Fraunhofer ISE - tel: +49 761 4588 5257, fax: +49 761
4588 9275 - email:
andreas.bett@ise.fraunhofer.de
Sources: Depeche IDW, Fraunhofer ISE press release,
18/02/2005
Editor: Nicolas Condette,
nicolas.condette@diplomatie.gouv.fr

Leave a comment

Your email address will not be published. Required fields are marked with *