Analysis of the Damp Heat Stability of Lightweight Silicon Heterojunction Solar Modules with Various Encapsulation Materials

In this work, we fabricated particular lightweight mini-modules with various encapsulation materials and configurations. The overall thickness of the module is less than 2 mm. The specific weight is only 1.75 kg/m2 compared to conventional glass/back sheet modules whose specific weight is 9.5 kg/m2. The performance degradation of the modules after 1000 hours of damp heat (DH) test is investigated. The results show that the TPO encapsulated module has the lowest efficiency degradation of 3.3% compared to the other encapsulants investigated in this study. This indicates that TPO is a promising material for protecting SHJ solar cells from damp heat induced degradation (DHID). Furthermore, the efficiency degradation of the lightweight module after 1000 hours of DH was reduced from 3.3% to 1.2% by replacing the ETFE front sheet with PVF/PET. The DH stability of the front sheet/back sheet modules was significantly improved and is very similar to that of the glass/back sheet module. The results of this work could provide significant reference information for the development of damp heat stable lightweight SHJ solar modules.