Document Type

Conference Paper

Rights

This item is available under a Creative Commons License for non-commercial use only

Disciplines

Environmental sciences, Civil engineering, Architecture engineering

Publication Details

Second International Conference on Whole Life Urban Sustainability and its Assessments; Conference Proceedings: SUE-MoT 2009. Loughborough, UK, 22-24 April, 2009.

Abstract

Research studies have shown that the initial energy embodied in a building can be as much as 67% of the operational energy over a 25 year period. With growing global concerns over material and resource consumption and the emissions of CO2 into the atmosphere, the energy embodied in buildings constructed in town and cities becomes important and one of the key issues that needs to be tackled in the design stages in order to strive towards sustainable buildings design. In this paper, a hybrid embodied carbon dioxide equivalent (CO2eq) methodology used to assess the CO2eq embodied in buildings is presented. The hybrid methodology consists of an Input-Output (I-O) and a process-based analysis. The I-O analysis is undertaken using re-derived Supply and Use and Input-Output data for Ireland which includes energy inputs into imported construction products and materials and construction sub-sectoral energy data. The Grand Canal Apartments in Dublin, Ireland is used as a case study. The buildings substructure, internal walls, floors, stairs, frame and roof was analysed in the study. The Irish construction sector is divided into five different sub-sectors, each having direct input-output energy intensities and accounting for different construction activities. The construction sub-sectoral I-O direct energy intensities ranges from 25.61tCO2eq/m€ for general fit-out to 493.27tCO2eq/m€ for the use of construction machinery. When embodied CO2eq analysis is carried out at the construction sub-sectoral level, there is a methodological improvement in the calculated values for the direct input-output as well as the total energy intensities over other traditional hybrid methods because of the use of disaggregated sub-sector construction data which can be more specifically applied to the type of construction project being considered. This hybrid methodology further makes use of disaggregates factors that disaggregate the energy supply sectors in the Input-Output analysis into individual sub-sectors supplying energy to the construction sector. Increasing population in urban cities and town means that new building and other social infrastructure needs to be constructed. Embodied CO2eq emissions of new buildings should be used as one of the sustainable indicators to measure the whole life sustainability of buildings. The embodied CO2eq of a Grand Canal apartment building was estimated to be 0.00718tCO2eq/€. Energy saving efforts and sustainability initiatives in the construction sector such as considerations to embodied CO2eq of building materials, selection and design options can play a significant role in reducing the overall future CO2eq of the country. Reduction in the CO2eq embodied in buildings helps to tackle environmental pollution but needs however to be balanced with economic and social costs in order to achieve an overall sustainable urban solution.