The Potential of Nature-Based Solutions in Urban Heat Mitigation and Building Energy Savings

This study explores the impact of typical nature-based solutions (NBS) on mitigating urban heat islands (UHI), improving thermal comfort, and reducing building energy consumption. Evaluated NBS includes green roofs, permeable pavements, and street trees. An integrated modeling approach that combines climate change modeling and building energy simulation was developed to assess the effectiveness of NBS in different climates and urban contexts. The results reveal that street trees are the most efficient at urban heat mitigation, with a maximum reduction in air temperature, mean radiant temperature, and Universal Thermal Climate Index (UTCI) at 0.27 °C, 4.23 °C, and 0.88 °C, respectively. Green roofs, particularly intensive ones, can also contribute to cooling the environment and reducing building energy use, with varying efficacy depending on the climate and urban built environment. Scenario analysis shows that green roofs can significantly reduce energy demand throughout the year in hot and sunny regions. Additionally, the installation of green roofs in urban contexts characterized by low-rise buildings can result in nearly zero annual energy demands for cooling or heating. Overall, this study advances scientific understanding of the role of NBS in urban planning and underscores the importance of tailoring these solutions to specific local conditions.