Performance Analysis of a Novel Lens-Walled Compound Parabolic Concentrator Photovoltaic System

A low concentration Compound Parabolic Concentrator Photovoltaic system (CPC-PV) system has the advantages of reduced PV cell size, increased efficiency, and stationary operation. The solid dielectric CPC-PV has a larger half acceptable angle compared with that of a same-sized mirror CPC. However, the solid dielectric CPC needs a considerable amount of solid dielectric. As an alternative, a 2.5 X lens-walled CPC was designed; its design included a thin lens coated with a reflective film on the outside surface of the lens. The shape of the lens was formed through internally rotating the parabolic curves of a CPC by a small degree around the top end points of the curves. The refraction of the lens would then allow the lens-walled CPC to concentrate light from a wider incidence angle. The test on the different incidence angles of lights showed that when the incidence angle is smaller than 35°, the optical efficiency of the lens-walled CPC is always above 46.7%, which is more stable on the incidence angle changed than that of the mirror CPC. Moreover, the lens-walled CPC weighed and cost less compared with the solid CPC. Thus, the lens-walled CPC is precisely the combination of the advantages of the mirror CPC and the solid CPC, and has the potential to be promoted for a wide range of practical applications.