Module level analysis of low breakdown voltage solar cells in urban landscapes

Abstract

In urban environments, more and more building added and building integrated photovoltaic (PV) systems are found. These systems use conventional solar modules which have a poor performance under non-uniform illumination conditions. When the module is partially shaded, either at least one
subgroup is bypassed or the module current is limited by the current of the worst performing cell. This leads to significant and disproportionate power losses. One way to address this issue is to implement a solar module made of low reverse breakdown voltage (BDV) solar cells.
A thermo-electric simulation framework was developed in MATLAB to replicate two types of commercially available low BDV solar cells: Sunpower Maxeon gen2 and gen 3 cells. Using the above model the potential and performance of solar modules in urban landscapes has been evaluated. A comparative study of solar module models built with these cells and placed on three different locations on a single rooftop having completely different irradiance profiles has been assessed. A solar module with 3 bypass diodes made of gen 3 solar cells has a better performance than module made of gen 2 cells. This accounts not only for better forward parameters of gen 3 cells but also its improved mismatch losses owing to lower reverse breakdown voltage and better temperature coefficients.
The usage of low reverse breakdown solar cells is beneficial in conditions where partial shading is predominant. Other advantages of using these solar module over other technologies is there is that there is no need of any additional electronic components.