Accurate performance modeling of bifacial and monofacial PV technologies: From laboratory validation to real-world deployment

Accurate modeling of photovoltaic (PV) performance under varying conditions remains a key challenge in improving energy yield predictions. This study introduces a novel method based on the Single Diode Model (SDM) for modeling the performance of advanced PV technologies across both indoor and outdoor environments. The method determines five physical parameters: series resistance, shunt resistance, photocurrent, reverse saturation current, and diode quality factor, using key current-voltage (I-V) curve points and a single arbitrary point. It derives nonlinear equations and analytical expressions to efficiently extract the optimal values of these parameters. A major innovation is the introduction of confidence intervals with new expressions that define precise upper and lower bounds for each parameter, enhancing convergence speed and ensuring physical relevance. The method was validated on a range of bifacial modules (HJT, TOPCon, PERC) as well as monofacial modules and strings (p-Si, m-Si, PERC, and CIS) through tests conducted under controlled indoor conditions at the Green Energy Park (GEP) testing laboratory and in an outdoor environment at the GEP facility. Results show excellent agreement between experimental and modeled data, yielding Root Mean Square Error (RMSE) values below 0.1102 A for bifacial and 0.0352 A for monofacial modules under indoor conditions. Under outdoor conditions, the RMSE remained below 0.1778 A for bifacial modules, 0.0999 A for monofacial modules, and 0.0726 A for monofacial strings. These findings confirm the method's accuracy and robustness, offering a powerful tool for reliable PV performance modeling under diverse operating conditions.