This study uncovers the impact of geographic variability on the distribution of sunlight on vehicle surfaces, focusing on two distinct scenarios: the flat-surface cargo area of a small delivery truck and the entire body of a commercial passenger vehicle. We employ a commuter pattern driving profile in Germany and a broader analysis incorporating random sampling of various road types and locations across Europe and the USA using LIDAR-derived topography and OpenStreetMap data. Our findings reveal significant irradiation inhomogeneity patterns shaped by the geographic landscape, road configurations, urban planning, and vegetation. The research identifies topography as the primary factor affecting irradiation distribution uniformity, with the vehicle’s surface orientation and curvature serving as secondary influencers. These insights hold immense potential for improving the design and efficiency of vehicle-integrated photovoltaic systems, presenting a foundational knowledge base from which to optimize energy capture in diverse environmental conditions.