Simulating the impact of urban morphology on energy demand in blocks- A case study of dwellings in Nanjing

This study aims to explore the impact of urban morphology on the energy demand of urban residential blocks, using dynamic simulation tools―HTB2 and Virvil Sketchup Extension. The study was conducted in Nanjing, a city with a hot summer and cold-winter climate that was under great challenges of reducing heating and cooling energy consumption. In particular, the simulation was applied to 35 residential blocks characterized by four types including point-type, linetype, courtyard-type and hybrid-type. Seven indicators were chosen to reveal each block's morphological features and total energy use intensity (EUI) was adopted to assess energy demand. Through correlation analysis and multiple regression analysis, this study verified a quantitative correlation relationship between urban morphology features and energy performance of buildings at block scale. Building density was the only factor that could significantly affect the total EUI of point-type and line-type residential blocks, while building orientation was the only factor affecting the total EUI of hybrid-type residential blocks significantly. No indicators could significantly affect the total EUI of the courtyard type residential blocks. It should be noted that surface-to-volume ratio was the only factor that could significantly affect the total EUI of all urban blocks, regardless of block morphological types. Overall, this study provides a reference for urban planners and designers to reduce building energy consumption at the master planning stage. Moreover, this study also suggests a general method for analysing the impact of urban morphology on building energy consumption in blocks.