Spectrally-resolved measurement of concentrated light distributions for Fresnel lens concentrators

Abstract

A test method that measures spectrally resolved irradiance distribution for a concentrator photovoltaic (CPV) optical system is presented. In conjunction with electrical I-V curves, it is a means to visualize and characterize the effects of chromatic aberration and nonuniform flux profiles under controllable testing conditions. The indoor characterization test bench, METHOD (Measurement of Electrical, Thermal and Optical Devices), decouples the temperatures of the primary optical element (POE) and the cell allowing their respective effects on optical and electrical performance to be analysed. In varying the temperature of the POE, the effects on electrical efficiency, focal distance, spectral sensitivity, acceptance angle and multi-junction current matching profiles can be quantified. This work presents the calibration procedures to accurately image the spectral irradiance distribution of a CPV system and a study of system behavior over lens temperature. IEEE, 1994), pp. 1791-1794. 7. P. Espinet-González, R. Mohedano, I. García, P. Zamora, I. Rey-Stolle, P. Benitez, C. Algora, A. Cvetkovic, M.Hernández, J. Chaves, J. C. Miñano, and Y. Li, "Triple-junction solar cell performance under fresnel-based concentrators taking into account chromatic aberration and off-axis operation," in CPV8 Conf.

Assessment of the optical efficiency of a primary lens to be used in a CPV system

“…A straightforward way to solve this issue is to place the input irradiance sensor also into the chamber. A second alternative is the use of an enclosure around the lens so that it can be warmed independently of the solar cell (Besson et al, 2016). The wall of the enclosure between the lens and the cell must, of course, be transparent for all the wavelengths of interest.…”

Characterization of the influence of temperature on achromatic mirrors by means of METHOD

“…The experimental setup [1,6], which has been developed to characterize the spectral electrical performances for lenses, needs to be adapted to a new kind of Primary Optical Element (POE), the mirror. The process implemented to obtain images of the concentrated spot from the achromatic mirror includes an opal diffuser, located at the focal point of the mirror under test that scatters light preventing straight light.…”

Measuring primary lens efficiency: A proposal for standardization

“…In recent years several experimental techniques have been developed to characterize optics for CPV. This article draws on all those works both those reported by other labs [1][2][3][4][5][6] and the experience accumulated in the CPV systems group at the Solar Energy Institute of the Technical University of Madrid (IES-UPM) [7][8][9][10][11].…”