Modeling in support of methods of module testing for long term environmental durability

We begin from the basic premise that the primary enemies of PV modules are heat, light and moisture, plus numerous other possible stressors which may or may not be participants, depending upon the specific location of the module. We have adopted a Coffin-Manson model to estimate what the effects of thermal cycling might be upon the PV module in support of empirical observations. It describes part of the environmental durability to be anticipated from subject modules (1). Although this model ignores the effects of humidity, solar irradiance, voltage variation and other mechanical and chemical stresses, it does offer us an estimate of the equivalence of a test methodology to a part of the real world environment. A realistic example of its use is described and calculated.