Estimating the impact of urban densification on high-rise office building cooling loads in a hot and humid climate.

Izabella Lima; Veridiana Scalco; Roberto Lamberts

Urban densification is recommended as the most advantageous solution for the sustainable growth of cities. However, when considering energy consumption, its effects are perceived as complex and conflicting. Two of the main consequences of urban densification are changes in the climate resulting from the urban heat island (UHI) effect and in the incident solar radiation - resulting from the surroundings buildings geometry, which can affect the energy consumption of a building in opposite ways. In a hot climate region a decrease in the direct solar radiation could be a positive factor but the UHI effect would be negative in terms of reducing energy consumption. Thus, the overall effects of densification need to be evaluated for these regions. Herein, the influence of the urban environment geometry on the thermal load of office buildings in a city with a hot and humid climate was evaluated. Energy dynamics simulations were carried out by the modeling of the surrounding geometry and considering the UHI effect. When the urban environment was considered in the energy simulations average reductions in the thermal load of 16–18% were observed, highlighting the importance of this approach. Shading was found to be the major factor related to this reduction.