PV module reliability scorecard - Round 1

Abstract

Solar PV system component reliability is key to longterm success for the PV industry, given the 25-year lifespan of PV generators. PV modules are one key component needed to deliver on the lifetime production of PV systems, as they are the engines that convert the fuel from the sun into the electrons for use here on Earth. This research presents the results from the first round of reliability testing for commercially available PV modules based on accelerated stress tests conducted at the CSIR Energy Centre. Four module types with a specific bill of materials (BOM) were subjected to a series of accelerated stress tests as defined by the C450 international standard. Pre- and post-stress characterizations were conducted to quantify the changes in safety and performance due to the accelerated stress. PV module power decreased by less than 3% for all modules subjected to mechanical loads, humidity-freeze, thermal cycling, and PID. However, the degradation rates among the four BOMs differed significantly (p<0.001) following the thermal cycling sequence. PV module power decreased by as much as 9% following the damp heat stress prior to the final stabilization. The work was conducted to demonstrate the value of accelerated stress testing now available in South African to support the PV industry. The round one results highlight potential differences in the long-term performance of PV module BOMs in the field, supporting the value of accelerated stress testing to de-risk investments in PV generators.