Investigating Spectral, Thermal and Positional Effects on the Performance of 5-Junction CPV Cells

Concentrator photovoltaic (CPV) cells are sensitive to environmental conditions, including solar spectral composition and operating temperature, as well as cell alignment relative to the Fresnel lens. Using a research-based CPV module, provided by AZUR SPACE Solar Power and deployed in South Africa, the study provides insights into the effects of spectral composition, operating temperature and cell misalignment on the performance of two variations of the 5C46 cell under operational conditions. Solar spectral data, using Average Photon Energy, indicated that Port Elizabeth is predominantly blue-rich relative to AM1.5d, with seasonal variations. Measurements revealed temperature differences of approximately 10 °C between cells along the edge and in the centre of the module, resulting in power variations of up to 0.328 W. Positional displacement showed that small lateral x–y misalignments had a limited effect on Voc and Isc, but a noticeable influence on power. Variations in cell height with respect to the Fresnel lens affected all electrical parameters. Spectral analysis confirmed that a version of the 5C46 cell performed as designed with improved performance in red-rich spectra. These findings emphasise the importance of spectral considerations, effective thermal management, and accurate optical alignment in the design of CPV modules.