Urban microclimate and energy consumption: A multi-objective parametric urban design approach for dense subtropical cities

Abstract

Climate change within the urban contexts is a crisis that cities are confronting globally. This issue poses numerous negative consequences such as thermal discomfort and increased energy usage within the building sector. This is especially the case in Western Sydney, Australia, where the average maximum temperature has risen by 7–8 °C within the past 30 years. This increase in temperature is highly concerning, since this region is witnessing rapid urban and infrastructural development and is proposed as the third-largest economy of Australia. Temperature changes in this region will also result in considerably increasing the electricity used for cooling purposes. This paper presents a parametric approach driven multi-objective optimization methodology to discover optimum design solution based on the urban microclimate and cooling energy demand of multi-functional buildings within this urban context. Mitigation measures including a range of design factors at both building (typology and window to wall ratio) and urban scales (aspect ratio and urban grid rotation) are further suggested for developing context sensitive optimum urban layouts. The resultant solutions indicate an improvement in urban thermal comfort, cooling and heating energy use by up to 25.85%, 72.76%, and 93.67%, respectively.