Analysis of Embodied Energy of High-Rise Office Buildings in Hong Kong

Embodied energy of the building is sufficiently determined by buildings structure. Prior studies have examined the embodied energy of office buildings for alternative wood, steel and concrete structure frames. However, most of the studied buildings were low-rise and small-scale. The embodied energy of high-rise office buildings is still largely unknown. Reinforced concrete frame structure is predominant in high-rise buildings. The aim of this paper is thus to investigate the embodied energy demand of high-rise office buildings with reinforced concrete frame structure. The research was carried out through a critical literature review and case studies of eight high-rise office buildings from Hong Kong. The data analysis was conducted through the use of life cycle assessment (LCA) modelling tools SimaPro. The results indicate that energy embodied in material manufacturing take the largest part (about 96%) of the overall embodied energy use of the high-rise buildings, followed by transportation and on-site construction. Moreover, galvanised steel, structural steel and reinforcing bar are identified to be the top three energy-intensive building materials for reinforced concrete frame buildings. The conclusions suggest that those energy-intensive building materials are with a significant potential for the reduction in embodied energy demand. This paper profiles the embodied energy use of high-rise office buildings. The findings should help to highlight the importance of extending the energy conservation to the before-use stage of the buildings.