Mechanical strength evaluation of curved surface and large-area crystalline silicon solar cell modules without encapsulant and cover glass

Abstract We fabricated encapsulant-less, curved, large-area crystalline silicon (c-Si) photovoltaic (PV) modules using a polycarbonate (PC) base and front cover. To investigate their mechanical strength against static loads and impact durability, we conducted sandbag load tests and hail impact tests. The PC front cover demonstrated excellent durability against loads and impacts due to its high elastic modulus and impact resistance. In the sandbag load test, the front cover did not undergo plastic deformation even under prolonged loading, and we observed no damage caused by contact between the front cover and the solar cells. Furthermore, in the hail impact test, there was no damage to the solar cells nor scratches on the front cover due to the hail impact, suggesting that the PC front cover can serve as an alternative to conventional cover glass. These results confirm that encapsulant-less, curved, large-area c-Si PV modules possess sufficient mechanical strength comparable to conventional modules.