Multi-scale life cycle energy analysis of residential buildings in Victoria, Australia – A typology perspective

Abstract

The residential building sector is a substantial contributor to energy use in Australia. In existing studies, life cycle energy (LCE) of residential buildings is seldom evaluated from the multi-scale perspective and such considerations rarely consider building typologies. This study presents a bottom-up framework to evaluate the LCE of residential buildings at multiple scales, including the component, building and regional levels. This framework can synthetically connect LCE between different scales and assess inter-scale impact in the built environment. In this framework, residential buildings are classified by embodied impact attributes (housing type, construction year, and construction type) and operational impact attributes (occupancy schedule, fuel type, and climate zone). In this paper, the framework is further applied to evaluate the LCE of residential buildings in the context of Victoria, Australia. The research results provide valuable references about energy intensities of various residential building typologies. The research findings suggest that operational energy (OE) of new housing has reduced significantly because of the improvement of technologies and the energy-saving requirement by the government. As a result, the proportion of embodied energy (EE) in dwelling's life cycle has increased from 9%–35% (old dwellings) to 66%–71% for dwellings built after 2011. At the regional scale, the LCE is composed of 79% OE and 21% EE in Victoria. The largest part of OE is contributed by the energy use for heating (39%), and appliances are the second most energy consumers (32%). Meanwhile, the energy embodied in concrete accounts for the largest part (908 PJ) of total EE. The comprehensive profile and interplay of LCE across different scales can help decision-makers to identify the key contributor to LCE and take targeted measures to improve the energy performance of the built environment.