Optical Design of an Infrared Non-Imaging Device for a Full-Spectrum Solar Energy System

A solar collector/receiver system for a full-spectrum solar energy system is being designed by a research team lead by Oak Ridge National Laboratory and the University of Nevada, Reno. [1,2] This solar energy system is unique in that it utilizes the majority of the solar spectrum by splitting the infrared (IR) and visible energy for two different end uses. The visible light will be used for day lighting and the IR energy for electrical power generation. This paper is concerned with the optics that will provide uniform irradiance of the IR energy on the thermal photovoltaic (TPV) array. The benchmark full-spectrum collector/receiver and prototype TPV array have been built [3], so the work performed here is to match the two systems together for optimal performance. The design consists of a non-imaging (NI) system for the IR flux incident on the TPV array mounted behind the secondary mirror. Results of the ray-tracing analysis of the different systems tested are presented.