4. 1 PV Module Design, Manufacture, Performance and Reliability
PV Module, Bifacial, LeTID, Simulation
Summary / Abstract:
This work aims at supporting a better understanding of the LeTID phenomenon. It relies on accelerated stress test under current injection to emulate light exposure for three batches of bifacial PV modules (mono and cast mono silicon modules). Indoor characterization is carried out regularly at different irradiance levels and electrical parameters are estimated from it. The paper goes through a qualitative analysis describing the evolution of electrical characteristics and a quantitative one relying on descriptive statistics to identify the drivers behind the LeTID degradation, their role during degradation and regeneration phase and the unbalanced response to different irradiance levels. The analysis reports that a convergence of the long-term stabilization power regardless of the injected current and highlights that the performance losses are driven globally by Isc, then Voc and FF. Isc has a prominent role in the degradation phase and FF drives the power recovery for the regeneration phase. In addition, LeTID phenomenon appears significantly stronger at low irradiance levels for the rear face. The maximal degradation is reduced by 0.2%/(100W/m²) between 200 W/m² and 1200 W/m².