Miodrag Forcan

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Reduction of long-term degradation effects represents a long-time challenge in photovoltaic (PV) manufacturing industry. Modelling of long-term degradation types and their impact on maximum power of PV systems have been analysed in this article. Brief guidelines for PV cell-based modelling of PV systems have been illustrated. Special study case, PV string consisting of 12 PV modules, has been modelled in order to determine degradation and mismatch power losses. Modified methodology for prediction of annual energy production from PV string, based on horizontal irradiation and ambient temperature experimental measurements at the location of Belgrade, has been developed. Coefficient named “degradation factor” has been introduced to include and validate degradation power losses. Economic considerations have indicated evident money income reduction, as a consequence of lower annual energy production related to long-term degradation.


PV string, energy production, long-term degradation, degradation factor, mismatch losses

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