Assessing the Long-Term Performance Degradation of PV Modules in the Sub-Saharan Environment
Abstract
This experimental study evaluates the long-term performance and degradation of solar PV modules exposed to the tropical climate of the sub-Saharan. The methods employed for the assessment are Visual inspection, I-V curve characterization, and thermal evaluation by IR imaging. In determining the state of the bypass diodes, the process of partial shading was applied. After thirteen (13) years of exposure in actual outdoor operation, modules showed a reduction in short circuit current (Isc), from 7% to 16.4%, with an average drop of 11.7% compared with the nameplate values. The decline in open-circuit voltage (Voc) ranges from 11.4% to 17.1% with an average reduction of 14.8%. Reduction in Fill Factor (FF) ranges from 11.3% to 24.2%, and a power loss is of 34.5% to 41.4%. EVA browning was the most severe and widespread defect observed through the visual analysis of the modules.