Abstract: Accurate determination of the temperature coefficient of maximum power (TCPmax) is essential for evaluating photovoltaic (PV) module performance. This work compares two techniques for TCPmax determination: a conventional outdoor method and a novel approach based on long-term monitoring. The research was conducted on grid-connected PV installation located at Algiers. Three representative PV modules exhibiting different failure severity levels were selected for analysis. Results show good agreement between two methods, with deviations not exceeding ± 5% in most cases. However, TCPmax values were found to decrease as the severity of module degradation increased, indicating a strong correlation between failure severity and temperature sensitivity. The proposed method, while requiring a longer data collection period, offers a cost-effective, non-intrusive alternative suitable for in-field applications. The comparative analysis highlights the advantages and limitations of each technique and demonstrates the potential of the proposed method for real-time performance diagnostics and degradation assessment in PV systems.

Keywords: PV module degradation, TC of maximum power, TCPmax determination, Sun-Tracking method, Data-Driven monitoring, Temperature effect

Pages: 468-475