Thermal reliability analysis of polymeric materials for PV technology

The success of the Photovoltaic industry will rely on demonstrating long term reliability of the polymeric materials used in modules. Qualification tests according to the IEC PV module standards may provide a benchmark entry into the industry, but does not assure long term operation. PV module manufacturers benefit from thermal endurance analysis and material relative thermal index (RTI) or relative thermal endurance (RTE) ratings as it provides knowledge of the material´s thermal aging behavior as a basis for comparison with other polymeric materials. The RTI/RTE rating of a material is an indication of the material´s ability to retain particular properties (physical, electrical, etc.) when exposed to elevated temperatures for an extended period of time. This paper examines the UL 746B and IEC 60216 accelerated thermal analysis programs in relation to RTI and RTE ratings, respectively.