DUET: A Novel Energy Yield Model With 3-D Shading for Bifacial Photovoltaic Systems

Bifacial photovoltaic (PV) performance models strive to accurately quantify rear-incident irradiance. While ray tracing are optically rigorous, they require significant computational resources; faster view factor (VF) widely adopted but user-defined loss factors approximate rear shading and irradiance nonuniformity, introducing uncertainty in energy yield predictions. This article describes DUET—a bifacial PV model that calculates optical electrical based on a physically representative array geometry. DUET’s novel algorithm pairs 3-D VF with deterministic ray-object intersections capture 2-D shade-inclusive profiles while minimizing cost. Series parallel combination of current–voltage curves nonuniformity throughout the module array. provides validation against open-access system measurements from test site Roskilde, Denmark, comparison other software tested there [1]. modeled agrees measured data within ?1.56% for fixed-tilt ?0.65% horizontal single-axis tracked (HSAT) systems. Mean absolute error (MAE) hourly power is 14.2–15.0 mW/Wp 17.3–18.3 HSAT, depending temperature applied. Comparing two rear-facing pyranometers, MAE values 2.8 W/m $^{2}$ 3.7 HSAT among lowest errors reported at this site. DUET computationally efficient modeling geographic, temporal, structural specificity determine use or be used directly design optimization.