Pushing energy yield with concentrating photovoltaics

Abstract

A 4J CPV module achieving 41.4 % efficiency at CSTC is presented in this paper. The high efficiency is enabled through the combination of high quality achromatic full-glass lenses with high efficiency 4J solar cells. This module has been built to demonstrate the potential of CPV module technology when improving the efficiency of the optical elements as well as the solar cell performance by integrating more junctions. The characteristics of the full-glass lens module are compared to a conventional Fresnel lens module. High efficiency is one of the keys to increase the energy yield of CPV power plants and to make the technology more competitive. Another aspect is the use of diffuse, scattered and albedo light resources which is typically not converted in high-concentration PV modules. Hybrid CPV modules combine high concentration PV with a flat-plate technology like silicon to push the energy yield even further. In this work, we present latest developments of our EyeCon hybrid module technology at Fraunhofer ISE and demonstrate the potential of a bifacial submodule (136 cm2) consisting of one silicon solar cell on which six concentrator cells are mounted. The technology has significant potential to extend the application area where CPV technology can compete with conventional flat plate PV.