Bifacial Gain Assessment of Bifacial PV Panels: A Long Term Field Study

In recent years, bifacial photovoltaic technology has gained increasing attention in the solar energy industry due to its potential for higher energy generation compared to traditional monofacial PV panels. Bifacial PV modules can capture light from both the front and rear surfaces, allowing them to harness more of the available solar irradiance and potentially increase overall system efficiency. However, accurately assessing the bifacial gain, or the additional energy generated by the rear side of the module, remains a challenge for system designers and researchers. This research paper presents a practical approach to evaluating the bifacial gain of PV panels under real-world conditions of one-year field study. Yearly solar irradiance and ambient temperature is logged at Hyderabad from September 2023 to August 2024. For the monofacial panel, the front irradiance is calculated. For the bifacial panel, both the front and rear irradiance are evaluated. The total irradiance for the bifacial panel is then calculated based on the front and rear irradiance measurements. Finally, the bifacial gain is calculated by comparing the bifacial yield with the monofacial energy yield. This study observed bifacial gains of up to 19.24%.