Highly concentrated photovoltaics (HCPV) is a technology that provides regenerative electricity with maximum efficiency and thus low resource consumption. Thus, this technology is ideal for regions with a high proportion of direct solar radiation. Multiple solar cells made of III-V semiconductor compounds are used, in which multiple very thin solar cells are stacked on top of each other in order to make more efficient use of the solar spectrum. They are combined with optical lenses that concentrate the solar radiation on a tiny solar cell surface. The modules are tracked synchronously with the course of the sun by biaxial tracking units.
The new record was achieved in photovoltaics, which are certainly not poor in records, as part of the CPVMatch research project. The focus of this EU-funded project was the industrial implementation of highest efficiencies for concentrator modules and thus the reduction of the gap between research results and commercial production. Under the leadership of Fraunhofer ISE (Freiburg, Germany), a consortium of research and industrial partners from Germany, Italy, Spain and France was involved in the research.
The project dealt with all steps of the manufacturing process for concentrator modules - from the materials used to the cell manufacturing process and the production facilities to the module manufacturing process. The project partners achieved two major results. By using innovative cell architectures for multi-junction solar cells - using new materials, processes and production equipment - they were able to optimize the production of quad-junction solar cells. They also improved the design of highly concentrating modules - primarily by modifying the optical elements based on achromatic lenses. The combination of highly efficient four-axis solar cells with achromatic lenses has now led to the new record efficiency of 41.4% for a module with an area of 122 square centimeters.