Humidity, Temperature, and Voltage: Task Group 3
Task Group 3 is focused on testing for humidity, temperature, and voltage stresses.
The ingress of moisture with or without electrical bias has been shown to cause corrosion and charge/ion transport in PV modules. Temperature and humidity have been used as accelerated stress tests for PV modules for many years. There are multiple humidity and humidity/electrical bias degradation modes with widely varying acceleration factors. The group's development of true accelerated lifetime tests will take variation of environmental conditions into account.
Group 3 continues to assess the performance of field-aged modules. The group is collecting performance data from modules with more than 10 years of exposure in hot humid climates in an effort to identify humidity-related failure and degradation modes.
Group 3 has been supporting the effort underway in IEC TC82 to develop standard test methods for measuring Potential Induced Degradation (PID). Two standard test methods were developed, one in a damp heat chamber and one using aluminum foil. These were published as IEC 62804 "Test methods for detection of potential induced degradation of crystalline silicon photovoltaic (PV) modules” and can be utilized by the PV industry to characterize the susceptibility of PV products to PID. Once PID is well understood, a PID Qualification Test will be developed probably as a part of the IEC 61215 PV Module Qualification Test.
IEC 62892-1 "Testing of PV modules to differentiate performance in multiple climates and applications – Part 1: Requirements for testing" is being developed by IEC Technical Committee 82
Compendium of photovoltaic degradation rates, Prog. In PV, FEBRUARY 2016
Crystalline silicon PV module degradation after 20 years of field exposure studied by electrical tests, electroluminescence, and LBIC, Prog. In PV, NOVEMBER 2015
John H. Wohlgemuth and Michael D. Kempe, "Equating Damp Heat Testing with Field Failures of PV Modules", Proc IEEE PVSC, 2013, 126-131.
While some materials are posted to the website, please contact your regional leader to more closely follow the activities.
John Wohlgemuth — NREL, representing the Americas
Neelkanth Dhere — Florida Solar Energy Center, representing the Americas
Tadanori Tanahashi — AIST, representing Japan
Alan Xu — Canadian Solar, representing China
Other leaders and regional groups are welcome!