Analysis and comparison of optical performance and collectible solar energy between multi-sectioned compound parabolic concentrator (CPC) and restricted exit angle CPC

Abstract

This study was conducted to analyse and compare the optical performance and collectible solar radiation energy of two different Compound Parabolic Concentrators (CPCs): multi-sectioned CPC (hereafter called M-CPC) and restricted exit angle CPC (hereafter called R-CPC) so as to ascertain the best CPC for photovoltaics applications. For easy comparison between M-CPC and R-CPC, a standard CPC (hereafter called S-CPC) was also designed. A detailed ray trace simulation analysis was undertaken to compare ray trace diagrams, angular acceptance, optical efficiency and energy flux distribution of the three CPCs. Results indicated that the angular acceptance and optical efficiency of the three CPCs were the same (100%) between 0º and 15º incidence angles, but significantly varied above 15º. On the other hand, solar radiation distribution on the solar cell was more uniform for the M-CPC than that of S-CPC and R-CPC. In terms of annual solar radiation collection, results indicated that both S-CPC and M-CPC collected approximately the same amount of energy (49,500 W/m2). Furthermore, the energy collected by S-CPC or M-CPC was higher than that collected by R-CPC by about 23%. Therefore, based on the energy flux distribution and collectible solar radiation energy, M-CPC is the best concentrator for photovoltaics applications.

Keywords: Multi-sectioned CPC, restricted exit angle CPC, optical performance, collectible solar radiation energy