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Abstract: In Australia, a pervasive response to increasing atmospheric greenhouse gasses and the exchange of these gasses between the atmosphere and forests has been to focus on storing carbon (C) in forested landscapes. However, the amount of C stored and able to be stored in the landscape, which is often called carbon carrying capacity, is commonly over-estimated and over-emphasised. This occurs, in part, due to a focus on the continent’s most C-rich forests when discussing landscape C storage or carbon carrying capacity, and by failing to account for wildfires that will prevent all forests from becoming old and C-rich. These effects on forest age-class structure and thus C-stocks, in the Australian landscape currently tend to be overlooked at the policy level. Underemphasised is the widely recognised role of wood products in greenhouse gas mitigation, both as a C-stock and by providing society with low emission products. Improving atmospheric outcomes will only be achieved if variation in landscape C stocks is accurately described and the full role of forests in greenhouse gas mitigation including the role of wood products is explored and reflected in policy. [Copyright &y& Elsevier]

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]

Australians are one of the world’s highest per capita emitters of greenhouse gases, yet the country’s target for emissions reductions by 2030 remains modest. This paper looks at policy options for Australian cities to deliver faster emissions reductions than the national commitment level. The main focus is on an accelerated reduction in emissions from urban road transport, through technological improvements and behaviour changes. Targets are proposed for improved emissions intensities, to bring Australia much closer to US and EU performance expectations. A range of behaviour change measures is then tested on Melbourne and Sydney, the Sydney analysis using MetroScan-TI, an integrated evaluation framework, to explore how behaviour changes might enhance emissions outcomes. The potential contribution of public transport is a particular focus. The paper concludes that, with sufficient political will, Australia could reduce its 2030 road transport emissions to 40% below 2005 levels. This is a much larger reduction than the current 26–28% Australian target but is more consistent with longer term pathways to acceptable carbon budgets. [ABSTRACT FROM AUTHOR]

In this paper we propose a market mechanism for regulated exit of highly emissions intensive power stations from the electricity grid. The starting point is that there is surplus capacity in coal fired power generation in Australia. In the absence of a carbon price signal, black coal generation capacity may leave the market instead of high emitting brown coal power stations. We lay out options for a mechanism of regulated power station closure using a market mechanism. Plants bid competitively over the payment they require for closure, the regulator chooses the most cost effective bid, and payment for closure is made by the remaining power stations in proportion to their carbon dioxide emissions. This could overcome adverse incentive effects for plants to stay in operation in anticipation of payment for closure and solve the political difficulties and problems of information asymmetry that plague government payments for closure and direct regulation for exit. We explore the issues theoretically and provide empirical illustrations. These suggest that closure of a brown coal fired power station in Australia could yield emissions savings at costs that are lower than the social benefits. The analysis in this paper is applicable to other countries. [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]

Abstract: Nowadays renewable sources are being used as clean sources to generate electricity and to reduce the dependency on fossil fuels. The uses of renewable sources are being increased in electricity generation and contributed to reduce the greenhouse gas emission. The function of any electrical power system is to connect everyone sufficiently, clean electric power anywhere and anytime of the country. This can be achieved through a modern power system by integrating electrical energy from clean renewable sources into the nation''s electric grid to enhance reliability, efficiency and security of the power system. The paper on the status of review the driving force of the generation of renewable energy and proposing electrical energy generation from renewable sources to be ensured at least 20% of total energy of Australia. This paper has been studied the existing electricity generation capacity of Australia from renewable and non-renewable sources. Optimal electricity generation from renewable sources has been examined. The environmental impact of electricity generation from renewable sources has been considered. Under this paper the yearly average wind data of past 20 years and above for some meteorological stations of Australia have been used. The prospective electricity generation from wind turbines and solar photovoltaic panels has been proposed in the paper that will increase electrical energy of the power grid of Australia. It was estimated the capital cost of prospective electricity generation farms from wind and solar PV sources. [Copyright &y& Elsevier]

Abstract: Savannas comprise a large proportion of the terrestrial land surface and are highly varied in their composition, structure and function. These characteristics alter land–atmosphere exchanges of heat, water, carbon dioxide and other trace gases, which feed back to the climate at multiple scales. Australian savannas provide significant ecosystem services and further systematic scientific study is needed to sustainably manage these ecosystems. We undertook an interdisciplinary research effort to understand the patterns and processes of carbon, water and energy cycles across northern Australian landscapes across scales from point to region. We quantified the land surface–atmosphere exchanges across the vast region of Australian savannas using a hierarchical, integrated measurement and modelling approach to determine regional greenhouse gas and water budgets. The research team comprised groups from seven institutions and four countries. The research effort comprised of a multi- year measurement and modelling endeavour and culminated in an intensive field program held in September 2008 (late dry season). The program aimed to improve our knowledge of the spatial and temporal variability of land–atmosphere exchanges and the processes driving them as well as our ability to remotely sense them and simulate them using land surface models, which are crucial components of Global Climate Models. We attempted to robustly integrate small scale processes, such as leaf photosynthesis to larger scales applicable to modelling and remote sensing for the savanna region. In this paper we provide the scientific background and our overall approach to the program with reference to the papers in this “Savanna Patterns of Energy and Carbon Integrated Across the Landscape” (SPECIAL) issue. [Copyright &y& Elsevier]

Abstract: This paper evaluates Australia''s proposed emissions reduction policies in terms of the implied rates of decarbonization of the Australian economy for a range of proposed emissions reduction targets. The paper uses the Kaya Identity to structure the evaluation, employing both a bottom-up approach (based on projections of future Australian population, economic growth, and technology) as well as a top-down approach (deriving implied rates of decarbonization consistent with the targets and various rates of economic growth). Both approaches indicate that the Australian economy would have to achieve annual rates of decarbonization of 3.8–5.9% to meet a 2020 target of reducing emissions by 5%, 15% or 25% below 2000 levels, and about 5% to meet a 2050 target of a 60% reduction below 2000 levels. The paper argues that proposed Australian carbon policy proposals present emissions reduction targets that will be all but impossible to meet without creative approaches to accounting as they would require a level of effort equivalent to the deployment of dozens of new nuclear power plants or thousands of new solar thermal plants within the next decade. [Copyright &y& Elsevier]

Geoengineering is a high-stakes policy issue that calls for research and debate that is pluralistic, reflexive and socially accountable. This paper reflects on an Australian geoengineering scenario project as a practical and innovative platform for informing governance. We produce multi-scale scenarios—representing Australia and the world— built on four fundamentally different archetypes, in which three include geoengineering. According to the four scenarios: greenhouse gas emissions continue increasing to 2050 but not long beyond; except with accelerated technology development and adoption, climate change impacts by 2050 become globally relevant; the risk of unilateral geoengineering deployment without adequate governance is low; and the framing of geoengineering deployment can be characterized as either climate mitigation, adaptation or optimization. Australia’s role in geoengineering can be described as passive in the global context, but Australia can benefit from an early transition to a low-carbon economy. A review of the evolution of ideas throughout the exercise reveals a process of shared learning that helps to focus governance discussions around key issues. This study is one step towards increasing the presence and influence of the Asia-Pacific in geoengineering discussions, and highlights the value that a tailored scenario exercise can bring to governance discussions. [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]

Knowledge of real-world greenhouse gas emission rates for traffic is necessary for forecasting transport greenhouse gas emissions. This paper presents greenhouse gas emission rates that assist forecasting and modelling greenhouse gas emissions from light vehicles, i.e. private passenger vehicles and light commercial vehicles under realistic traffic conditions. It develops confidence intervals for market shares by categories for fuel or energy efficiency on the Australian market for new light vehicles for the period 2016–2030. The model estimates realistic market scenarios by simulating likely variations of capital and running costs of alternatives for car buyers and by considering buyers’ willingness-to-pay for fuel/energy efficiency. The results suggest that market forces will be insufficient to promote battery electric vehicles and plug-in hybrid electric vehicles in Australia. On average the widths of the 95% confidence intervals for greenhouse emission rates are about 10–15% of the magnitudes of the emission rates, so that analysts can forecast transport greenhouse gas emissions with a reasonable level of certainty. The study suggests that policy interventions to accelerate the uptake of low or zero emitting vehicles may be required. [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]

This paper is the first of a two part study that considers long term, least cost, GHG (greenhouse gas) abatement pathways for an electricity system. Part 1 formulates a planning model to optimise these pathways and presents results for a single reference scenario. Part 2 applies this model to different scenarios and considers the policy implications. The planning model formulated has several constraints which are important when considering GHG abatement and widespread uptake of intermittent renewable generation. These constraints do not appear to have been integrated into a single planning model previously, and include constraints on annual GHG emissions, unit commitment, storage, plant dynamics and intermittent renewable generation. The model prioritises overall abatement, and therefore does not include a price on carbon or support for any particular technology. The model is applied to Australia's NEM (National Electricity Market) as an example. All model inputs – for technologies, demand, and meteorological data – are from the most current and authoritative public sources. As such, the results are transparently derived and both policy and technology neutral. For the reference scenario presented here, key technologies are wind from 2015, gas generation from 2030, and solar generation from 2040. [ABSTRACT FROM AUTHOR]

This paper is the second of a two part study that considers least cost, greenhouse gas abatement pathways for an electricity system. Part 1 of this study formulated a model for determining these abatement pathways, and applied this model to Australia's NEM (National Electricity Market) for a single reference scenario. Part 2 of this study applies this model to different scenarios and considers the policy implications. These include cases where nuclear power generation and CCS (carbon capture and storage) are implemented in Australia, which is presently not the case, as well as a more detailed examination of how an extended, RPS (renewable portfolio standard) might perform. The effect of future fuel costs and different discount rates are also examined. Several results from this study are thought to be significant. Most importantly, this study suggests that Australia already has utility scale technologies, renewable and non-renewable resources, an electricity market design and an abatement policy that permit continued progress towards deep greenhouse gas abatement in its electricity sector. In particular, a RPS (renewable portfolio standard) appears to be close to optimal as a greenhouse gas abatement policy for Australia's electricity sector for at least the next 10–15 years. [ABSTRACT FROM AUTHOR]

Residential or ‘rooftop’ solar PV can play an important role in providing renewable energy, thus offsetting fossil fuel based generation and associated greenhouse gas emissions. In Australia, subsidies are offered to encourage the deployment of residential PV in the form of Renewable Energy Certificates (RECs) and Feed-in Tariffs (FiTs). This paper provides a literature review of existing work which assesses renewable energy in Australia, and delves deeper into a residential PV specific analysis of available data across the five criteria of installation, employment, market maturity, FiT settings and environmental outcomes to assess successes, failures and impacts of Australian residential PV policies between 2001 and 2012. This analysis identifies overall success with regard to environmental and deployment goals, and limited success in the goal of renewable energy industry promotion, which is devoid of indigenous manufacturing. In addition, impacts, including the dominance of the FiT as the initial stimulus for rapid PV deployment, cost impacts on electricity bills for various FiT settings, and the dependence of PV employment numbers on the continuation of the FiT are also identified. Finally, inequitable outcomes due to the FiT, such as cross-subsidisation from non-solar to solar households are also detailed. [ABSTRACT FROM AUTHOR]

The use of oil in road transport contributes significantly to global greenhouse gas (GHG) emissions in addition to rapidly depleting this non-renewable resource. Emissions can be greatly reduced by the total replacement of petroleum-based vehicles with electric vehicles using a combination of hydrogen and battery energy storage technologies. This paper analytically reviews the potential reduction in Australian road transport GHG emissions through the total replacement of petroleum-fueled vehicles with hydrogen and battery electrical vehicles by 2050. If electricity for hydrogen production & storage and battery charging is sourced from the national electricity grid, it is estimated that emissions can be reduced by between 56% and 73% in 2050 compared to the Australian Government’s Bureau of Infrastructure, Transport and Regional Economics (BITRE) projections, depending on the current range of government carbon price projections. Emissions can be reduced even further by supplementing grid electricity with standalone renewable electricity dedicated to hydrogen production and storage. It is found that there is more than sufficient renewable energy resources within Australia (particularly solar and wind) to meet the significant increase in the annual electricity generation that would be required to implement this strategy. [ABSTRACT FROM AUTHOR]

The Australian government has recently pledged a reduction in GHGs emissions of 26–28% below the 2005 level by 2030. How big is the challenge for the country to achieve this target in terms of its present emissions profile, recent historical trends, and the contributions to those trends from key proximate factors contributing to emissions? In this paper, we attempt a quantitative judgement of the challenge by using decomposition analysis. Based on the analysis it appears the announced target will be quite challenging to achieve if the average annual mitigating effects from economic restructuring, energy efficiency improvements and movement towards less emissions-intensive energy sources in evidence over 2002–2013 continued through to 2030; however, if the contribution from these mitigating sources in evidence over 2006–2013 can be sustained, achievement of the target will be much less challenging. The challenge for government then will be to provide a policy framework to ensure the more pronounced beneficial impacts of the mitigating factors evidenced during 2006–2013 can be maintained over the years to 2030. [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]

International commercial flights (with the exception of flights between countries in European Union including Iceland, Norway and Liechtenstein) are currently not subject to greenhouse gas emission reduction regulation. To formulate effective and efficiency policy to manage greenhouse gas emissions from air transport, policy makers need to determine the emissions profiles of all airlines currently flying into their country or region. In this paper, we use 2012 data on airlines' aircraft characteristics, passenger load and cargo load (obtained from statistics reported by Australian Government Bureau of Infrastructure, Transport and Regional Economics) to estimate the volume and carbon efficiency on each international route flying to and from Australia. This is the first study to use actual passenger and cargo load data to determine the greenhouse gas (specifically CO 2 ) efficiency of airlines operating in the Australian international aviation market. Airlines' CO 2 emission profile is dependent on many factors including but not limited to the aircraft used, payload, route taken, weather conditions. Our results reveal that the airlines’ CO 2 emission profile is not only dependent on the aircraft used and the number of passengers but also the amount of cargo on each flight. [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]

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]

Abstract: Climate change due to greenhouse gases emission from fossil fuels has prompted several governments to channel resources in the commercial utilisation of renewable energy sources. Solar energy is one of the renewable energy sources that is highly untapped and underutilized. Australia has the highest average solar radiation per square metre of any continent in the world. This paper will focus on the need to improve solar energy utilisation in Australia, challenges facing it and the future benefits. This study shows successfully storing and transferring solar energy will ensure that this energy source will make a significant contribution to Australia''s electricity grid supply in the future and Australia will be well positioned to assist in meeting its growing clean energy demand. [Copyright &y& Elsevier]

Abstract: Australia has a very sunny climate, with a very high demand for air conditioning. Implementing solar assisted air conditioning is an ideal option to achieve a high solar fraction which leads to a significant amount of energy and greenhouse gas emission savings. Solar assisted air conditioning systems are environmentally friendly by being constructed in a way that minimises the need for chlorofluorocarbons CFC, Hydro chlorofluorocarbons HCFC or Chlorofluorocarbons HFC refrigerants and by using a low grade thermal renewable energy, therefore, making them energy efficient and environmentally safe. They can be used either as stand-alone systems or with conventional AC, to improve the indoor air quality. Solar cooling is a new and a fast growing technology compared to other fields of solar energy applications. On the other hand most of the current solar cooling applications are demonstration projects in nature; the technologies are advancing yet still need a lot of additional design, planning, development, and research efforts. T now solar assisted air conditioning''s main obstacles are the high installation costs, and the lack of knowledge and familiarity with this technology between designers, developers and architects. In this paper a feasibility study is carried out to assess a solar assisted air conditioning system for an office building under three of Queensland''s subtropical climates; Rockhampton, Gladstone, and Emerald. The technical aspects of a proposed solar cooling system are investigated. Cooling load profile for a proposed reference building was obtained using TRNSYS software under the influence of these different climates. An electric vapour compression pump, with 2.5 coefficient of performance (COP) for cooling is used as a reference system to assess the primary energy consumption, assuming 80% of primary energy consumed by the reference conventional system is replaced by solar energy. The results of analysing the proposed system indicated that an 80% of the primary energy savings can be achieved by installing 50 m2 of solar collectors and 1.8 m3of hot water''s storage tank under the three selected climates. [Copyright &y& Elsevier]

Abstract: Domestic water heating in Australia conventionally uses electric resistance heating storage or gas fuelled water heaters. The Australian electricity supply has some of the highest greenhouse gas emissions factors in the world. Consequently, water heating is responsible for approximately 24 percent of residential sector greenhouse gas emissions in Australia. To assist households to move towards an energy efficient, low carbon future, a suite of market intervention programs to support solar hot water uptake have been introduced at both state and federal levels. These programs aim to improve the capacity of industry to deliver solar solutions, reduce the emissions intensity and net cost of household water heating, and increase the market share of the solar water heating sector. Incentives include: [•] Point of sale rebates and certificate-based programs for energy efficiency and renewable energy; [•] Regulations for new houses that encourage solar water heating installations; [•] Community awareness programs; and [•] Training programs for installers to ensure that tradespeople have the competencies to size systems and the skills to install them correctly. In some jurisdictions the incentive programs were performance-based, but in others a fixed rebate amount was available for all systems having performance above a minimum threshold. These programs have lead to the widespread expansion of the industry, with an almost doubling of the proportion of households with solar water heaters between 1999 and 2011. Installations in new homes have seen an even more marked increase: For example, regulations for new homes in the state of Victoria require the installation of a solar water heater or rainwater tank. This program has seen the adoption of solar water heaters in new homes increase fro m around 5% in 2004 to over 70% in 2011. Across most of Australia there are proposed regulations limiting the emissions intensity of replacement water heaters which will effectively ban resistance electric water heaters in most situations. Recently both South Australia and Queensland commenced their program for existing houses. It is expected that in the future these programs will drive an even greater uptake, which will go some way to insulating Australian households from price increases that may result from carbon driven future increases in the cost of energy. This paper discusses the various approaches and outcomes of the different programs and provides analysis of the basis of program success or improvements. Learning relevant to market interventions worldwide include [•] Continuity in program operation is necessary to allow industry to grow in a sustainable way. [•] Basing the incentive on independently derived performance results provides industry with a means of differentiating better products and provides purchasers with appropriate guidance. [•] Rebate program design should consider the consumer''s purchasing priorities. For example, a point of sale discount awarded as part of the purchase transaction aligns with the urgency of the purchasing process and does not require additional cash to be available from the purchaser. [•] Design of the schemes can not only produce a greater market share, but can also encourage the manufacture of lower greenhouse gas emissions products. [•] Market interventions can have unintended consequences, so the programs need to be monitored and flexibility maintained to changes to avoid poor outcomes. [Copyright &y& Elsevier]

Abstract: Transport is Australia’s third largest and second fastest growing source of greenhouse gas (GHG) emissions. The road transport sector makes up 88% of total transport emissions and the projected emissions increase from 1990 to 2020 is 64%. Achieving prospective emission reduction targets will pose major challenges for the road transport sector. This paper investigates two targets for reducing Australian road transport greenhouse gas emissions, and what they might mean for the sector: emissions in 2020 being 20% below 2000 levels; and emissions in 2050 being 80% below 2000 levels. Six ways in which emissions might be reduced to achieve these targets are considered. The analysis suggests that major behavioural and technological changes will be required to deliver significant emission reductions, with very substantial reductions in vehicle emission intensity being absolutely vital to making major inroads in road transport GHG emissions. [Copyright &y& Elsevier]

Australian power generators produce approximately 170 TWh per annum of electricity using black and brown coals that accounts for 170 Mtonne of CO2 emissions per annum or over 40% of anthropogenic CO2 emissions in Australia. This paper describes the results of a techno-economic evaluation of liquid absorption based post-combustion capture (PCC) processes for both existing and new pulverised coal-fired power stations in Australia. The overall process designs incorporate both the case with continuous capture and the case with the flexibility to switch a CO2 capture plant on or off depending upon the demand and market price for electricity, and addresses the impact of the presently limited emission controls on the process cost. The techno-economic evaluation includes both air and water cooled power and CO2 capture plants, resulting in cost of power generation for the situations without and with PCC. Whilst existing power plants in Australia are all water cooled sub-critical designs, the new power plants are deemed to range from supercritical single reheat to ultra-supercritical double reheat designs, with a preference for air-cooling. The process evaluation also includes a detailed sensitivity analysis of the thermodynamic properties of liquid absorbent for CO2 on the overall costs. The results show that for a meaningful decrease in the efficiency and cost penalties associated with the post combustion CO2 capture, a novel liquid sorbent will need to have heat of absorption/desorption, sensible heat and heat of vaporisation around 50% less in comparison with 30% (w/w) aqueous MEA solvent. It also shows that the impact of the capital costs of PCC processes is quite large on the added cost of generation. The results can be used to prioritise PCC research in an Australian context. [ABSTRACT FROM AUTHOR]

Abstract: Coal fired electricity is a major factor in Australia’s greenhouse gas emissions (GHG) emissions. The country has adopted a mandatory renewable energy target (MRET) to ensure that 20% of electricity comes from renewable sources by 2020. In order to support the MRET, a market scheme of tradable Renewable Energy Certificates (RECs) has been implemented since 2001. Generators using biomass from eligible sources are able to contribute to GHG emission reduction through the substitution of coal for electricity production and are eligible to create and trade RECs. This paper quantifies the potential biomass resources available for energy generation from forestry and agriculture in the Green Triangle, one of the most promising Australian Regions for biomass production. We analyse the cost of electricity generation using direct firing of biomass, and estimate the required REC prices to make it competitive with coal fired electricity generation. Major findings suggest that more than 2.6 million tonnes of biomass are produced every year within 200 km of the regional hub of Mount Gambier and biomass fired electricity is viable using feedstock with a plant gate cost of 46 Australian Dollars (AUD) per tonne under the current REC price of 34 AUD per MWh. These findings are then discussed in the context of regional energy security and existing targets and incentives for renewable energies. [Copyright &y& Elsevier]

Abstract: Limited data regarding soil carbon (C) sequestration potential and biosequestration potential in arid and semi-arid environments is an impediment to appropriate policy formulation directed at greenhouse gas abatement. This paper assesses the terrestrial C biosequestration and biodiversity restoration potential of the semi-arid mulga lands of eastern Australia by measuring above and below ground C, and by making floristic biodiversity assessments in old grazing exclosures. Grazing exclusion increased water infiltration rates and water retention capacity in the soil. Exclosures also had increased herbaceous cover and decreased bare ground. Biodiversity benefits included higher species richness and increased abundance of native grasses, many of which have become locally rare under increased grazing pressure. The study indicates that in the absence of grazing, soil and above ground biomass, when combined, has potential carbon sequestration rates of between 0.92 and 1.1tCO2-eha−1 year−1 over a period of approximately 40 years. The contribution to these figures from soil C sequestration is approximately 0.18tCO2-eha−1 year−1, with above ground biomass contributing an additional 0.73–0.91tCO2-eha−1 year−1. If 50% of eastern Australia''s mulga lands (half of 25.4 million ha) were managed for C sequestration and biodiversity through the control of all herbivores, then annual sequestration rates could reach between 11.6 and 14MtCO2-eyear−1 which is between 2 and 2.5% of Australia''s annual emissions. The potential to sequester carbon and improve biodiversity outcomes in extensive semi arid grazing lands will require significant policy shifts to encourage and reward necessary land use change. [Copyright &y& Elsevier]

Abstract: Currently, Australia emits approximately 600 MT equivalent of CO2 annually, of which approximately 30% is directly linked to the electricity generation using both brown and black coals. To restrain the CO2 emissions, coal based power generators are looking to retrofit the existing power plants with commercially available technology for the post combustion capture (PCC) of CO2 as well as invest in the new power plants with high efficiency steam cycles. Since Australian coals are low in sulphur and the coal-fired power plants are well away from densely populated regions, the flue gas desulphurisation (FGD) and de- NOX regulations are currently not there for the coal based electricity generation in Australia. This is not an advantageous situation for straightforward retrofitting of the existing power plants with 30 wt% aqueous MEA based commercially available PCC technology that has very limited tolerance for SOX and NOX (less than 10 ppmv). In addition, Australia is a dry continent with very limited cooling water availability for the power plants. Hence, the Australian power generators are considering both the power and the post combustion CO2 capture plants to be air cooled. This paper, therefore, assesses the impact of introducing post combustion capture of CO2 on the existing and new Australian coal-fired power plants, both brown and black coal-fired, in terms of the cost of electricity generation, the cost of CO2 avoidance, the cooling water demand and the overall plant efficiency. The existing power plants are considered to be conventional subcritical and supercritical single reheat steam cycle based whereas the new power plant designs have allowed for ultracritical steam conditions (35 MPa, 922 K) with double reheat. The CO2 capture plants are considered to be either in service full time or in service on demand with 90% capture efficiency and the product CO2 ready for sequestration at 10 MPa and 313 K. The process and cost models for integrated power and capture plants have been obtained using ASPEN Rate-Sep, Steam-Pro, Steam-Master and PEACE software packages for process modelling and cost estimation. The results clearly show that an air cooled integrated power and capture plant has lower overall plant efficiency and slightly higher cost of electricity generation in comparison with a water cooled equivalent plant. An ultracritical single reheat power plant when integrated with capture plant that is in service full time has potential for lowest cost of electricity generation with minimum cost for CO2 avoidance. These results further show that replacing an existing turbine with a new LP turbine optimised for continuous steam extraction for CO2 plant duty minimises the adverse impact of PCC integration but the power generator looses the flexibility for electricity generation. The results also provide important insights into the major contributions to the increased cost of power generation. For both the existing and the new power plants, the amortised capital charge component dominates the cost of PCC integrated electricity generation. In spite of the large reduction in efficiency for Australian power plants when PCC is applied, it appears that reducing the capital costs of PCC will be at least equally important. This is an important outcome for the prioritization of research activities aimed at reducing the costs of capture. For example, the novel solvent development work for improved PCC technology should focus on increasing absorption rates at the same CO2 carrying capacity of the solvent to reduce the capital cost component. [Copyright &y& Elsevier]

Abstract: Woody regrowth is extensive on abandoned agricultural lands and developed pastures worldwide. Regrowth is actively controlled in working pastures, but it could be managed to offset greenhouse gas emissions from agriculture and other emitting industries with supplementary benefits for biodiversity conservation. This paper explores the case of Brigalow regrowth in the extensive pastoral landscape of north-eastern Australia. By synthesising current ecological knowledge with relevant socio-economic and policy considerations, it examines the potential of the Brigalow regrowth ecosystem to provide dual carbon/biodiversity benefits. Brigalow regrowth sequesters large amounts of carbon, especially when compared to other ecosystems from similar sub-humid climates. In addition, restoring regrowth is likely to have benefits for a wide range of native flora and fauna, including the endangered bridled nailtail wallaby. However, there are knowledge gaps relating to the landscape ecology of Brigalow regrowth and the impacts of management and climate change on carbon/restoration potential. Also, a conflict exists between short-term carbon sequestration and long-term restoration goals and we suggest a role for restoration thinning to resolve this. Regional demand for high biomass regrowth as a carbon offset is likely to be high but ambiguities in carbon policy threaten to diminish the use of natural regrowth for reforestation projects. [Copyright &y& Elsevier]

Abstract: Spontaneous combustion and low-temperature oxidation of waste coal in open-cut coal mines represents a potentially large source of greenhouse gas emissions. In this paper, emission fluxes of CO2 and CH4 from spoil piles and waste coal dumps measured at 11 mines in the Hunter Valley and Bowen Basin in Australia are presented. The data displayed considerable scatter, which is consistent with the inhomogeneous nature of spoil pile material and permeability of surfaces. Despite the scatter, emissions were able to be classified into three broad categories according to the intensity of the spontaneous combustion present in the material. Average emissions ranged from about 12 kg CO2-e yr−1 m−2 to 8200 kg CO2-e yr−1 m−2, depending on the intensity of the spontaneous combustion. There was also, within the scatter of the data, an approximately linear trend of increasing emission flux with increasing surface temperature. A key finding of the research is that the emission rates of greenhouse gases from spoil piles where there is no spontaneous combustion, but only low-temperature oxidation of coal and coal waste, are similar to the emission rates due to biological activity from vegetated surfaces. However, further research is required to quantify the degree to which spoil piles that have no spontaneous combustion contribute to the anthropogenic atmospheric CO2 burden. [Copyright &y& Elsevier]

Abstract: Post-combustion capture of CO2 is a key technology for the reduction of greenhouse gas emissions from Australian coal fired power stations. It is an emerging technology, which still faces significant challenges in scaling up to full commercial scale suitable for power station applications. To increase adoption by the power industry significant cost reductions in capital and operating cost must be realised. CSIRO has developed an integrated post-combustion capture R&D and pilot plant program aimed at bringing down the barriers for commercial deployment. This paper provides an overview of the program and its status. [Copyright &y& Elsevier]