Carbon assessment for urban precincts: Integrated model and case studies

The building sector is the largest contributor to global greenhouse gas (GHG) emissions. Over the years, sound tools have been developed to support the life-cycle assessment of building carbon emissions performance. However, most of these tools have been primarily focused on building-scale modelling and evaluation, leaving the emissions related to infrastructure and occupant activities as well as the carbon offsetting from implementing district-scale renewable energy systems, often neglected. The uptake of macro perspective carbon evaluations at the urban precinct level has been slow due to various barriers such as system boundary definition, quantification of complex inter-building effects, availability of comparable data, integrated modelling and uncertainties related to occupants' life styles. This research developed an integrated life-cycle model to support the precinct-scale evaluation of carbon footprint for a comprehensive understanding of the emission profile. This is expected to further support low carbon planning and (re)development of urban precincts. The model structure is underpinned by four major components at the precinct level, i.e. embodied, operational and travelling associated carbon emissions, as well as the carbon offsetting from solar energy harvesting. The utility of the proposed methodology is demonstrated through preliminary case studies on representative suburban precincts in Adelaide, South Australia. Comparative studies and scenario analysis are also involved to identify the critical elements affecting the overall carbon performance of urban precincts.