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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]

A Net Zero Energy Building (NZEB) is a term, subject to ambiguity, that could be used to describe a building with characteristics such as equal energy generation to usage, significantly reduced energy demands, energy costs equalling zero or net zero greenhouse gas (GHG) emissions. Despite lacking an authoritative definition of NZEBs, this relatively new emerging concept in Australia provides significant opportunities to reduce GHG emissions, energy usage and operational energy costs for buildings owners. This paper aims to explore the existing NZEB models, assess the progression of NZEB literature, identify key policies encouraging NZEB development and recognise potential areas of NZEB research. [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]

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]

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]

To be sustainable in energy usage in the future, there are two aspects that need to be considered: the energy supply or generation and the consumption side, including the closely linked construction and building industries which consume a large amount of energy. Essential requirements for energy efficiency are to produce less greenhouse gas emissions and to rely more on renewable energy sources for future sustainability. Policies for mitigation of the environment impact are having effects on both the supply and demand. While the former requires more alternate sources in smart grids and improved technologies for carbon capture and storage, the latter involves the reduction of energy wastes and greenhouse gas (GHG) emissions as prerequisites to green certification within the construction and building sector. Thus, access to sustainable, affordable, and secure energy is one of the major global strategic priorities to maintain and improve public health, sustain economic growth, and mitigate the effects of climate change. Toward this goal, many countries, including Australia, are investing in clean, efficient, reliable energy systems for a prosperous and environmentally sustainable future. Hence, exploring various options to ensure energy security by diversification of energy sources is an important step in meeting the future requirements and delivering clean energy to different industry sectors. This paper discusses options to manage the use of energy sources in the power generation and construction industries. Options for mitigation of environmental impact and for achievement of sustainable energy usage, such as building design with BIM, are discussed. [ABSTRACT FROM AUTHOR]

This paper examines the cost-effectiveness of subsidies (feed-in tariffs and renewable energy credits) paid for by electricity consumers to support the uptake of roof top photovoltaic (PV) systems by households in Australia. We estimate annual payback periods, and then regress these against the actual uptake of household PV and associated emission reductions, creating a relationship not apparent in other research. Sensitivity analysis reveals that the declining cost of PV panels had most impact on PV uptake followed by feed-in tariffs, renewable energy credits and the increasing cost of household electricity tariffs. Our modelling shows that feed-in tariffs were higher than necessary to achieve the resultant levels of PV uptake and that the low cost of PV panels and comparatively high electricity tariffs are likely to result in a continuing strong uptake of household PV in Australia. Our modelling shows that subsidies peaked in 2011 and 2012, with payback periods of three to four years, having since increased to five to six years. Emission reduction costs are expected to reduce from over AU$200 per t CO 2 e in 2013 to between AU$65 and AU$100 per t CO 2 e in 2020. Household PV reduced Australia’s emissions by 3.7 million t CO 2 e in 2013 (1.7% of Australia’s total emissions) and is expected to reach eight million tonnes (3.7% of Australia’s total emissions) by 2020. [ABSTRACT FROM AUTHOR]

Abstract: Building performance simulation has a key role in facilitating effective retrofitting of commercial buildings, an essential task to reduce Australia's greenhouse gas emissions. Simulation users commonly rely on assumptions for certain ‘hard-to-measure’ building and behaviour inputs, and the range of values use can significantly affect predicted energy consumption. New financing methods in Australia may attach financial risk to this simulation uncertainty. This paper reports on a study examining the sensitivity of total predicted building energy consumption to hard-to-measure simulation inputs for two template Australian office buildings; a 10-storey office tower located in a Central Business District (CBD), and a 3-storey office on the fringe of a CBD. The predicted energy consumption for the archetypes varied by more than 50% from baseline consumption for all Australian capital cities, using high and low assumptions. The input parameters that significantly influence energy consumption were found to be; cooling set-point, Information and Communications Technology (ICT) power density, ICT usage schedule, and lighting power density. A case study of a simple lighting upgrade to a 10-storey office building in Sydney showed that the payback period could vary from 2.4 to 10.3 years depending on the simulation assumptions used. [Copyright &y& Elsevier]