Systematic approaches to ensure correct representation of measured multi-irradiance module performance in PV system energy production forecasting software programs

Photovoltaic (PV) systems are gradually becoming larger to better leverage economies of scale. Still, project size and financing are governed by the confidence investors have in forecasted energy production. Default settings of PV module models in the two prevalent production forecasting software programs only poorly reproduce measured data for standard multi-crystalline module types. To address this issue, this work presents and applies systematic approaches to minimize differences between modeled and measured PV module efficiencies at multiple irradiance intensities. Optimized models considerably improve the agreement between model and measurement and have a significant impact on energy forecasts.