The buildings sector is responsible for approximately 23% of Australia’s carbon emissions. The Australian Sustainable Built Environment Council (ASBEC), the peak body for sustainability in the built environment, has identified that improving the minimum standards for energy efficiency of new buildings can assist in delivering carbon emissions reductions. One of the key tools in delivering improved building efficiency is the National Construction Code (NCC), which sets the minimum standards for new building work in Australia. The goal of the analysis undertaken for this project is to assess the contribution that the Code could make towards achieving GHG emissions reductions in line with overarching zero carbon targets.
This report is the Final Technical Report for the Building Code Energy Performance Trajectory Project accompanying the Built to Perform report. The intent of this report is to provide more details on the underlying assumptions and results from the modelling work performed. The study sought to identify energy efficiency measures for which the capital cost is outweighed by financial benefits (‘cost-beneficial’) from a societal perspective over a 40 year lifetime of the technology. In both residential and commercial buildings, a range of measures were found to individually achieve a benefit-tocost ratio (BCR) of between 1.0 and 1.5 (where, a BCR of 1 brings the same lifetime value as cost and a BCR of 1.5 brings 1.5 times the value, e.g. $15,000 for $10,000 cost) and when measures were combined there was increased potential to implement more measures together while remaining cost beneficial.
The target range of BCR was chosen so as to be consistent with the Australian Government’s Best Practice Regulation guidelines and Guidance Note on Cost-Benefit Analysis. The study examined multiple building archetypes located in four climate zones, covering Australia’s largest population centres (climate zones 2, 5, 6 and 7). Further to the examination of energy efficiency measures, on-site solar photovoltaic (PV) systems were considered, with standard panel-based systems on both residential and commercial archetypes and building integrated PV (roof tiles, wall systems, glazing, etc.) on commercial archetypes only. Alternative generation systems such as photovoltaic thermal systems, micro wind turbines and geothermal systems have not been included in this study.