Performance and energy loss mechanism of bifacial photovoltaic modules at a solar carport system

As photovoltaic modules are increasingly used in renewable energy systems, ensuring energy efficiency by reducing the levelized cost of electricity has become the focus of current research. Herein, the 1-year performances of both monofacial and bifacial photovoltaic modules were monitored, compared, and analyzed at a solar carport system in the Korean peninsula. The environmental parameters during the four seasons were investigated for both systems under ambient conditions. Irradiance was determined as the primary influencing parameter in the system. The energy yield of the bifacial module system was 3.08% higher than that of the monofacial system owing to rear-side absorption during the study period. The loss mechanism for this lower yield was determined by investigating the irradiance effect. It was attributed to low bifaciality due to cell properties (optical and electrical properties, and the sorting effect) and module properties (shading effects from the junction box cable and frame design, and glass grid effect), design of the carport system, and the albedo effect. These analyses revealed that the photovoltaic energy yield can be increased further by reducing these loss parameters at the carport system. This study can contribute to achieving higher energy yield from photovoltaic systems during field applications.