Roof orientation as a determinant of solar PV efficiency in sustainable smart City development

Abstract This study examines the integration of rooftop solar photovoltaic (PV) systems into building design, with a focus on roof orientation and pitch as key drivers of efficiency. Using PVSOL modelling and Durban meteorological data, it evaluates the impact of tilt, azimuth, and irradiance on generation. Results show that north-facing roofs (0° azimuth) with 30°–40° pitch deliver optimal annual GTI, while seasonal tilt adjustment (40° winter, 10° summer) improves yield by ~ 4.4%. North–South alignments generate ~ 28% more energy than East–West setups, with higher efficiency. Customised roof geometry aligned with building-integrated photovoltaics system (BIPVS) optimisation parameters enhances system capacity, conversion efficiency, and overall sustainability compared to standard configurations. These findings highlight the potential of affordable, PV-ready housing to advance smart city development and energy access in the Global South while supporting climate goals.