## 4 Conclusions  
This study investigated the performance of bPV modules in a temperate-climate setting (Cfa, Koppen classification) and an industrial rooftop-like test environment characterized by low ground clearance height (GCH) and limited tilt angles. We elucidated that non-uniform rear-side illumination, stemming from both ambient conditions (e.g., low diffuse to global radiation ratio) and site-specific factors (e.g., mounting structure characteristics), can substantially diminish bifacial performance in these non-ideal operational conditions. Despite the challenges posed by non-uniform rear-side illumination, bPV modules demonstrated considerable advantages over their conventional PV counterparts. Comparative analyses against two different PV modules revealed a consistent power increase of 4.3-7.8% with bPV glass/glass frameless technology. Similarly, a self-comparison of bPV modules in the monofacial configuration, where the rear side was fully obstructed, indicated a bifacial additional power estimate of approximately 2% under clear-sky conditions, which could escalate to 15% in overcast scenarios characterized by a high-diffuse-to-global-radiation ratio. This study delved into the influence of the mounting structure on bPV module performance across various tilt angles (0\({}^{\circ}\)-45\({}^{\circ}\)). It was demonstrated that even minor discrepancies in module alignment with structural beams can effectively negate any bifacial contribution. The absence of structural obstruction on clear days yielded an estimated additional power generation of up to 3.43% (+8.8 W), while less pronounced non-uniformity induced by the mounting structure still contributed to power enhancements of 1.3% (+4.13 W). In essence, these findings underscore the complex interplay between environmental, site-specific, and technological factors in determining the performance of bifacial PV modules. Despite the challenges posed by non-uniform rear-side illumination and mounting structure influence, bPV technology offers performance advantages over conventional PV  
Figure 10: Curves discrepancies (bPV2–bPV1). _I-V_ (**a**) and _P-V_ (**b**). MPP are identified with \(\times\) (bPV1) and \(\circ\) (bPV2). In (**a**), dotted lines show the estimated current difference at SC. modules even in not optimized installations. Further research and technological advancements are warranted to address these challenges and fully unlock the potential of bifacial PV technology in sustainable energy generation applications. Possible measures to reduce the production losses due to the effect of non-uniform rear-side illumination on industrial-like rooftops could include the use of half-cut cell modules and the proper separation of unavoidable blocking structural components, as well as the careful alignment of structural beams and rear cells. Their combination and alternative solutions still need to be investigated and optimized. conceptualization, A.G.-M., D.M. and E.O. ; methodology, D.M. and E.O. ; software, A.D.; validation, D.M., A.D. and E.O. ; formal analysis, A.G.-M.; investigation, A.G.-M. and D.M. ; data curation, D.M., A.D. and E.O. ; writing--original draft preparation, A.G.-M. and D.M. ; writing--review and editing, E.O. and S.L. ; visualization, A.G.-M.; supervision, S.L. ; project administration, S.L. ; funding acquisition, S.L. All authors have read and agreed to the published version of the manuscript. This study was conducted within the Agritech National Research Center and received funding from the European Union Next-GenerationEU (PIANO NAZIONALE DI RIPRESA E RESILENZA (PNNR)--MISSIONe 4 COMPONENTE 2, INVESTIMENTO 1.4--D.D. 1032 17/06/2022, CN00000022) and was also partly carried out within the MOST--Sustainable Mobility Center and received funding from the European Union Next-GenerationEU (PIANO NAZIONALE DI RIPRESA E RESILENZA (PNNR)--MISSIONe 4 COMPONENTE 2, INVESTIMENTO 1.4--D.D. 1033 17/06/2022, CN00000023). Not applicable. Data availability statementData available upon request.