Needs, Challenges and Approaches for New Service Life Estimation Models for PV Modules – Results from IEA-PVPS-Task 13 Subtask 1.4

The economic success of PV power plants depends crucially on the lifetime energy yield. The degradation effect and the total lifetime directly influence the produced electricity and therefore the cash flow. In most cases, lifetimes and degradation rates, which are used for the estimation of plant behaviour, are nowadays still not system specific, but based instead on average values of evaluations of older systems or data sheets. So, these values unfortunately have no direct correlation with the specific components of the respective PV system. Also, the mathematical models used for calculated power output typically expect linear degradation rates which are not found in real degradation processes found in the field. Activity 1.4 if IEA PVPS Task 13 developed an overview on service life prediction and degradation modelling of PV modules since they are the major component of PV systems causing degradation effects and for other components no comparable scientific data is available.