Spectral Admissibility Limits of Multifunctional Photovoltaic Films for Mobile-Cabin Glazing

Semitransparent thin-film photovoltaics can combine electricity generation, daylight transmission, and solar energy rejection, while passive radiative cooling introduces an additional requirement for atmospheric window emission. However, simultaneous functionality cannot be established by combining properties measured in separate devices. This study introduces spectral admissibility of multifunctional architectures (SAMA), an evidence-constrained method combining metric compatibility, non-compensatory admissibility, non-dominance screening, deterministic critical margins, and the identification of spectral-function gaps. Three directly comparable semitransparent organic photovoltaic states were assessed using average visible transmittance (AVT), power conversion efficiency (PCE), and total solar energy rejection (T-SER). The ABPF architecture achieved AVT of 49.62%, PCE of 12.19%, and T-SER of 77.49%, dominating the 11 nm Ag reference. The 40 nm TeO2 architecture remained non-dominated owing to its higher AVT of 50.86%. The critical symmetric perturbation for the ABPF–Ag PCE ordering was 0.175 percentage points. Independent transparent radiative cooling materials demonstrated high atmospheric window emissivity, but this property remains unverified for the photovoltaic states. SAMA distinguishes demonstrated performance, threshold-dependent admissibility, and unresolved integration potential, providing an upstream materials selection procedure for multifunctional glazing.