Applying rooftop photovoltaics (RPV) system can significantly reduce the demand for fossil fuels in cities, as well as contributing to sustainability and improving energy security. Accommodating the generated electricity is the primary issue worth investigating during large-scale promotion of RPV. Therefore, it is necessary to evaluate the accommodation potential of various subjects in the city in advance. This study focuses on assessing the potential of urban building to accommodate the PRV power generation. Firstly, the power generation of RPV and building energy consumption of Yangpu district were simulated. Then, the hourly supply and demand match was calculated to analyze the accommodation potential of buildings for local RPV electricity generation. The results showed that the total RPV electricity generation of Yangpu District were 1.82 × 109 kWh, and 66.96% of which can be used by buildings, accounting for 15.5% of the building energy consumption. If dividing the study area into 1 km × 1 km square blocks, and establishing microgrid to share RPV power generation among buildings, 92.86% of electricity production can be used. Considering the current solar energy accommodation policy (the accommodation ratio ≥ 95%), the available solar energy was 3.33  × 108 kWh.