The Techno-Economics of Selected PV Solutions on Building Facades, with Case Studies

The increasing prevalence of rooftop photovoltaics on European buildings has sparked interest in using façades and balconies as alternative surfaces for generating solar energy. This study examines the technical and economic performance of building-integrated photovoltaic (BIPV) installations on façades and balconies under real operating conditions. Four case studies from Poland are analysed using a combination of measured energy production data and simulations performed with the PVGIS tool. The analysis focuses on annual and seasonal energy yield, self-consumption potential, system costs, simple payback time and the role of module-level power electronics (MLPE) in mitigating the effects of shading and non-optimal orientations. The results demonstrate that, while façade-mounted PV systems generally have lower annual yields than optimally tilted rooftop installations, balcony and façade BAPV systems with MLPE can achieve high self-consumption rates, short payback periods (3–10 years) and favourable winter performance. These findings demonstrate that BIPV and BAPV systems on façades should be assessed using distinct technical and economic criteria, and highlight their potential to extend prosumer participation to apartment dwellers, thereby supporting a more inclusive urban energy transition.