Multivariate optimization towards energy balance with geometric constraints of building design and urban space intensity

Abstract

Rapid urbanization has caused extensive energy shortage and excessive carbon emissions, thus creating a constant demand for advancing building energy performance. Such work often involves complex analysis of urban geometry and non-uniform irradiance conditions for dynamic shading. This paper presents a novel method for comprehensive evaluation and optimization of building design with integrated photovoltaics. Key parameters include building-height-to-street-width ratio (H/W), number-of-floors (Nf), aspect ratio (r), floor area (Af), window-wall ratio (WWR), and photovoltaics’ tilt angle on façades (β). The developed model has been validated experimentally. A baseline model was produced to further highlight the differences between EUI with and without surrounding buildings. Results showed that H/W and Nf were positively correlated with deviations with Af. Higher Af and Nfimproved energy efficiency especially for low-to-mid rises. Heating and cooling presented no correlation with Nf for r≥5, while both loads reached peaks at r=4. As H/W increased, heating proportionally increased by 2.1 kWh/m2 while cooling decreased by 1.8 kWh/m2. These rates dropped as H/W increased. Energy production from façades increased when r>2, with a slope of 10,000 kWh per unit, and a variance of 190,000 kWh. The effect of β showed higher significance in cooling, heating, and production, especially for low H/W.