Study on the energy-saving effects of radiative material properties and material coating ratios in residential neighborhoods with different morphologies

The application of radiative materials (cool or super cool) on building surfaces has the potential to reduce summer energy consumption in buildings significantly. There is insufficient conclusive evidence regarding the energy-saving effects of cool and super cool materials applied to building façades. Therefore, in order to derive the effect of the material coating ratio of cool and super cool materials on the building façade on the building energy consumption, 106 schemes with varying material coating ratios were investigated by using EnergyPlus. The research findings indicate that applying cool and super cool materials to the building façade of high floors contributes more to energy savings in summer compared to middle and low floors. From an annual perspective, for residential neighborhoods of high-rise buildings, each floor using cool or super cool materials has an average annual energy saving rate (ESR) of 0.07–0.09%. The annual ESR can reach 1.9–2.4% when the façades of a 28-story building are entirely coated with cool and super cool materials. Additionally, point-type buildings have a higher energy-saving rate per material area than slab-type buildings. The energy-saving rate is not correlated with building density but is significantly related to floor area ratio, surface area ratio, and sky view factor. The conclusions of this study can provide a reference for the energy-saving retrofit of residential buildings in Nanjing.