Project DescriptionProject

BY Susan Wrigley / May, 2020

Project Description

Project Duration: 01/03/2020 – 30/08/2023


The efficiency of a solar cell or solar module is the most important feature that distinguishes PV technologies. The efficiency is not only decisive for the amount of energy that can be harvested from a limited area. It also determines the costs, resource consumption and thus the sustainability of solar energy production. A growing understanding of highly efficient solutions also promotes the development of optimised production processes and thus the competitiveness of the German photovoltaic industry. With 46% efficiency under concentrated sunlight, Fraunhofer ISE, together with SOITEC and CEA, holds the record for the most efficient quadruple solar cell in the world.

This value was confirmed at 508 times the concentration by the internationally recognized calibration laboratory AIST in Japan. Recently this value was surpassed by a 6-fold solar cell realized at NREL in the USA with an efficiency of 47.1%. The goal of the 50% project is to develop a multi-junction solar cell with 50% efficiency based on existing expertise and new findings, and thus to bring the efficiency of the world’s most efficient solar cell back to Fraunhofer ISE in Germany. Simulation calculations show that this goal can be achieved through the consistent further development of established technologies, in combination with shadow-reduced metal fingers and an improved anti-reflective layer.

The new infrastructure required for this will be available at the Fraunhofer ISE’s Center for Highly Efficient Solar Cells from summer 2020. Furthermore, the measurement technology is to be set up in order to be able to measure solar cells with up to 6 partial cells under spectrally adapted conditions. The new multi-junction solar cells are used in FLATCON® concentrator modules. Here, a module efficiency of more than 40% is expected for the first time. The 50% project aims to impressively demonstrate the excellence of applied photovoltaic research in Germany by setting new record efficiencies for solar cells and concentrator modules.

Frank Dimroth and Oliver Höhn on the World's Most Efficient Solar Cell

Malte Klitzke and Patrick Schygulla on Epitaxy und Material Optimization