Impact of tropical high-humidity climates on the stabilization phase of high-efficiency photovoltaic modules

This study investigates the stabilizing characteristics of high-efficiency crystalline silicon photovoltaic (PV) modules under tropical, high-humidity conditions. Three photovoltaic technologies: Passivated Emitter and Rear Cell (PERC), Tunnel Oxide Passivated Contact (TOPCon), and Heterojunction with Intrinsic Thin layer (HJT) were monitored under outdoor conditions in Thailand. Electrical parameters including maximum power (Pmax), short-circuit current (Isc), and open-circuit voltage (Voc) were continuously measured using I–V tracer compliant with IEC 60904-1-1:2020. Electroluminescence (EL) imaging was used to assess microstructural evolution and correlate radiative recombination behavior with electrical transitions during stabilization. The TOPCon and HJT modules required approximately 20 kWh/m² of cumulative irradiance to stabilize, whereas PERC modules required about 25 kWh/m². EL imaging analysis confirmed that TOPCon and HJT maintained superior structural integrity and recombination uniformity compared with PERC.