Potential assessment of rooftop photovoltaic in global cities considering economic feasibility

Rooftop Photovoltaics (RPV) serve as a promising distributed form of clean solar energy utilization, especially in highly dense urban areas. However, the global variation in the economic potential of RPV remains unknown. Here, we integrate the 3D building footprints and electricity demand to assess both the technical and economic potential of RPV at the global scale. The results show that the global technical potential of RPV in urban areas reaches 4048 TWh·yr − 1 , but the economic potential accounts for only 41.8% of the technical potential. China and the United States are the primary contributors to the technical potential, collectively accounting for over 50%, and face fewer economic impediments, as their economic potential accounts for over 80% of their technical potential. Meanwhile, Africa and South American countries face severe challenges, as despite the significant technical potential in some cities (ranking among the top 20), their economic potential is extremely low, with an average of only 19.57% of the technical. We posit that RPV possesses significant technical potential, capable of meeting the projected energy demand in 2050 as forecasted by the Energy Information Administration (EIA). However, achieving this target necessitates substantial technological advancement and a dedicated focus on energy equity, since the current economic potential appears sufficient only for development over the next decade.