Optical Methods for Indoor Characterization of Small-Size Solar Concentrators Prototypes

Abstract

The light collection properties of different types of solar concentrators have been investigated by applying conventional and innovative methods of characterization [1, 2]. Four types of optical methods were applied: i) a “direct” method using a laser beam as light source; ii) a “direct” method using a parallel beam simulating the direct component of solar light; iii) a “direct” integral method using a lambertian light source simulating the diffuse component of solar light; iv) an “inverse” method using a lambertian light source applied at the receiver side, thereby reversing the light path. The optical properties derived by applying the above three methods were: i) the local optical collection efficiency, resolved on the entrance point and direction of incidence ii) the overall optical collection efficiency under collimated light, resolved on direction of incidence; iii) the spatial and angular distribution of flux on the receiver.