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To fulfil the hunger for sustainable development, Australian construction sector seems to contemplate toward green design. Green-Star environmental rating system, one of the active building rating systems in Australia, has also been employed in New Zealand, and South Africa. To help engineers and designers obtain comprehensive visualisation on sustainable projects, this paper develops a model to evaluate energy consumption and greenhouse-gas emissions based on typical Australian commercial building alternatives. From that, this paper explains how to achieve points for “Energy” and “Life-cycle impacts” categories of this rating system. The model uses GaBi 8.1 platforms and shows relationships between building's energy consumption, and greenhouse-gas emissions released during the building lifetime. This paper provides insight into life-cycle greenhouse-gas emissions assessment for several typical commercial building fabrics in Australia. The developed model can also be conveniently modified to automate calculations for other credits under the Green-Star environmental rating system, and other environmental rating systems around the world. The study suggests that designers should consider the inverse relationship between building envelopes' total R-value with energy consumption and greenhouse-gas emissions. Another finding shows that materials used for building envelopes play a significant role to manage energy consumption as well as greenhouse-gas emissions amount during the building's life-cycle. [ABSTRACT FROM AUTHOR]

In this letter, we respond to the articles “Decoupling global environmental pressure and economic growth: scenarios for energy use, materials use and carbon emissions” by Heinz Schandl et al. (Journal of Cleaner Production, 132, 45–56) and “Australia is ‘free to choose’ economic growth and falling environmental pressures” by Hatfield-Dodds et al. (Nature, 527, 49–53). The authors of these papers suggest that policy settings are crucial for Australia to allow growing standard of living to coincide with lower environmental pressure and impact. Both papers make it clear that decoupling has not occurred in past, but stress that this does not mean it cannot occur in the future. Here, we undertake a comprehensive trend analysis by putting their decoupling scenarios into a historical context to assess the feasibility of decoupling economic growth from environmental impacts. To this end, we undertake a structural decomposition analysis to examine the drivers of a change in Australia's greenhouse gas emissions from 1976 to 2050. Using the well-known I = PAT equation, we appraise the contribution of population growth, affluence and technology in accelerating or decelerating the growth of emissions over the 75 year period. Our results suggest that population growth and affluence are key accelerators of greenhouse gas emissions. We argue that in order to decrease emissions from fuel consumption, unprecedented improvements in emissions intensity will be required both in Australia and globally. [ABSTRACT FROM AUTHOR]

Energy retrofits of buildings usually ignore the amount of embodied energy and greenhouse gas (GHG) emissions needed to reduce the operating energy and related emissions. Focusing on the Greater Melbourne Area (GMA), the fastest growing capital city in Australia, this paper analyses the embodied impacts of different dwelling stock retrofit programs using a combination of a top-down and a bottom-up approach. We look at dwelling stocks that have been built before 2005 (i.e., before a minimum 5-star rating in energy performance was introduced in Australia) because these are expected to consume, without any retrofit or upgrade, about 34.9 TWh of energy or emit 8.57 × 10 6 t-CO 2 eq GHG for heating and cooling every year. Retrofit options to improve their energy star rating range from relatively cheap and easy options (e.g., draught sealing) to relatively expensive options (e.g. double glazing of windows). If all these buildings' energy efficiency is improved to the level of a 6-energy rated dwelling across the metropolitan region, we can save about 25.5 TWh per year in heating and cooling energy (or 6.25 × 10 6 t -CO 2 eq GHG each year). However, the retrofit program is estimated to consume 4.75 TWh of embodied energy, or have 1.89 × 10 6 t -CO 2 eq embodied GHG emissions. This is equivalent to 50% of the annual heating and cooling energy for the stock, or 81% of operational GHG emissions due to heating and cooling of existing dwellings. Considering the total life cycle energy and GHG emissions over the life of the buildings, although reducing the operational heating and cooling energy will remain to be the primary driver for action, the proportion of the embodied impacts’ contribution is expected to increase in the coming years especially as the implementation of net-zero energy/emissions concepts become more commonplace. [ABSTRACT FROM AUTHOR]

Despite considerable mitigation efforts, global emissions from the electricity sector continued to grow in recent years. In Australia, the electricity sector is the largest CO 2 -emitting industry, contributing 35% of the country's total greenhouse gas emissions. The Australian government targets an 80% reduction of greenhouse gas emissions by 2050 relative to 2010. With a large variety and quantity of renewable energy resources, it is technically feasible and seems indispensable that Australia's electricity sector be largely decarbonised by 2050 in order to achieve this target. In this paper, scenario-based hybrid Life-Cycle Assessment is applied to calculate the economy-wide carbon footprints of seven electricity generation technologies in scenarios with differing renewable electricity penetration. This work is the first to apply a full life-cycle approach to scenario analysis of electricity generation in Australia. The findings are at the higher end of previously reported carbon footprint intensity ranges and above median values. However, even when taking into account indirect emissions along the technologies' life-cycles, the results indicate that the employment of different renewable energy technologies can potentially save a considerable fraction of Australia's greenhouse gas emissions. This makes renewables an essential option for climate change mitigation. [ABSTRACT FROM AUTHOR]

Abstract: The International Panel on Climate Change (IPCC) predicts an increase of 0.2 °C per decade for the next two decades in global temperatures and a rise of between 1.5 and 4.5 °C by the year 2100. Related to the increase in world temperatures is the increase in Greenhouse Gases (GHGs) which are primarily made up of carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4) and fluorinated gases. In 2004, the GHGs from agriculture contributed 14% of the overall global GHGs made up mainly of methane (CH4) and nitrous oxide (N2O) emissions. In Australia, the dominant source of CH4 and N2O emissions for the year ending June 2012 was found to be from the agricultural sector. With the recent introduction of the Clean Energy Act 2011, the agricultural sector of Australia is expected to develop appropriate GHG mitigation strategies to maintain and improve its competitiveness in the green commodity market. This paper proposes the use of Integrated Spatial Technologies (IST) framework by linking Life Cycle Assessment (LCA), Remote Sensing (RS) and Geographical Information Systems (GIS). The IST approach also integrates and highlights the use of Cleaner Production (CP) strategies for the formulation and application of cost-effective GHG mitigation options for grain production in Western Australia (WA). In this study, the IST framework was tested using data from an existing study (the baseline study) and two mitigation options. The analysis results revealed production and use of fertiliser as the “hotspot”, and for mitigation purposes was replaced with pig manure in option 1, whereas option 2 emphasised crop rotation system/s. [Copyright &y& Elsevier]