To further improve testing standards for PV modules, Fraunhofer ISE and Fraunhofer CSE have announced the launch of the PV Module Durability Initiative (PVDI). With the intention to provide additional information for investors, this initiative will offer a more robust testing protocol for a wide range of PV modules, exceeding the demands of IEC standard module certification. It is the first widely available program to generate extensive, quantitative reliability data for modules, relevant for their expected lifetime under different kinds of stress. The tests do not simply use pass/fail criteria but generate quantitative scores enabling the credible ranking of modules based on their likelihood to perform reliably.
The key differentiating features of the PVDI include extended accelerated testing, UV, damp heat with positive and negative voltage bias as well as dynamic mechanical stresses. Also included are typical stresses such as temperature cycling, humidity-freeze, and damp-heat, which have been extended in order to come closer to the actual lifetime stress of a module. The PVDI program further includes an R&D component and outdoor exposure testing which aims to constantly improve the tests and to offer better models for module lifetime predictions.