Quantification of the Reflection Effect in Bifacial PV Modules for Canal-Based Applications Using Field Measurement Data

In this study, we investigated the characteristics of rear-side irradiance in bifacial photovoltaic (PV) modules installed in a canal-based PV system using long-term field measurements. Irradiance data were collected at one-minute intervals over one year and then classified into six irradiance intervals, revealing that the 50–1000 W/m2 range accounted for over 95% of the total sum of instantaneous irradiance. A directional analysis of the front-to-rear irradiance ratios identified two representative groups, northeast-west and south-horizontal, based on correlation. Correction factors for estimating the rear irradiance were derived by applying the bifaciality factor to each group. These coefficients can serve as effective input parameters for the performance prediction models of bifacial PV systems installed over canals.