Comparative optical performance investigation of Cross Compound Parabolic Concentrators designed with the elimination of multiple reflections principle

Abstract

This paper evaluates low-profile solar concentrators with low-material consumption that improve the optical performance of Crossed-Compound-Parabolic-Concentrators (CCPCs) by using Eliminating-Multiple-Reflections (EMR). Three CCPC designs, LEMR, HEMR, and hybrid, were analysed using Monte-Carlo ray tracing, with optical efficiency and light flux uniformity as primary metrics. The LEMR and HEMR CCPCs achieved almost 88% average optical efficiency at the outlet aperture within the half acceptance angle. At the BCP, the LEMR CCPC attained an average efficiency of 85.7%, while the HEMR CCPC achieved an average efficiency of 85%. The hybrid CCPC achieved an average optical efficiency of 80% and 86% when the incidence angle was varied in the XY and YZ planes. The results showed that the non-uniformity of the light flux at the BCP remained low compared to the outlet aperture with changes in the incidence angle. A material consumption analysis revealed that the LEMR CCPC has the lowest material consumption as compared to the HMR and hybrid CCPCs and has a more uniform irradiance flux at the BCP. The LEMR CCPC has a relatively lower acceptance angle than the HEMR CCPC, making it suitable for a tracking system with a higher concentration ratio. The HEMR CCPC, on the other hand, can be used as a stationary concentrator due to its larger acceptance angle with a lower concentration ratio and can be applied in rooftops and building-integrated photovoltaics. Similarly, the hybrid CCPC has two different ranges of acceptance angles, making it advantageous for use in rooftops and building-integrated photovoltaics with seasonal tracking.