Measuring solar radiation and spatio-temporal distribution in different street network direction through solar trajectories and street view images

Under the dual pressures of rapid urbanization and global warming, the management of solar radiation has become an urgent issue to address. In this context, the potential regulatory role of urban street networks on solar radiation has garnered widespread attention. However, existing research lacks an understanding of the impact of street direction. By utilising street view data and solar trajectory simulation technology, it becomes possible to facilitate the revelation of spatiotemporal differences in solar radiation across streets with different direction. The results show that solar radiation is generally lower on north–south streets than on east–west streets. In terms of spatial differences, the average solar radiation in the fifth ring of Beijing is 25.38% higher than that in the second ring. Temporally, the average solar radiation in August, the highest month, is 15.98% greater than in October, the lowest month. Additionally, solar radiation on east–west street direction shows more intense variations in summer. A periodic variation in solar radiation was also discovered in relation to street angles, with different frequencies and amplitudes at 30° and 180°. This study is the first to focus on the directional attributes of roads at an urban scale. By utilising 100,000 street view images, it calculates and analyses the spatiotemporal distribution of solar radiation in Beijing during summer across different direction. The findings provide new insights into the relationship between the distribution of solar radiation and the morphology of urban roads.