37,497 research outputs found

    Engaging stakeholders in research to address water-energy-food (WEF) nexus challenges

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    The water–energy–food (WEF) nexus has become a popular, and potentially powerful, frame through which to analyse interactions and interdependencies between these three systems. Though the case for transdisciplinary research in this space has been made, the extent of stakeholder engagement in research remains limited with stakeholders most commonly incorporated in research as end-users. Yet, stakeholders interact with nexus issues in a variety of ways, consequently there is much that collaboration might offer to develop nexus research and enhance its application. This paper outlines four aspects of nexus research and considers the value and potential challenges for transdisciplinary research in each. We focus on assessing and visualising nexus systems; understanding governance and capacity building; the importance of scale; and the implications of future change. The paper then proceeds to describe a novel mixed-method study that deeply integrates stakeholder knowledge with insights from multiple disciplines. We argue that mixed-method research designs—in this case orientated around a number of cases studies—are best suited to understanding and addressing real-world nexus challenges, with their inevitable complex, non-linear system characteristics. Moreover, integrating multiple forms of knowledge in the manner described in this paper enables research to assess the potential for, and processes of, scaling-up innovations in the nexus space, to contribute insights to policy and decision making

    Economic and environmental strategies for process design

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    This paper first addresses the definition of various objectives involved in eco-efficient processes, taking simultaneously into account ecological and economic considerations. The environmental aspect at the preliminary design phase of chemical processes is quantified by using a set of metrics or indicators following the guidelines of sustainability concepts proposed by . The resulting multiobjective problem is solved by a genetic algorithm following an improved variant of the so-called NSGA II algorithm. A key point for evaluating environmental burdens is the use of the package ARIANE™, a decision support tool dedicated to the management of plants utilities (steam, electricity, hot water, etc.) and pollutants (CO2, SO2, NO, etc.), implemented here both to compute the primary energy requirements of the process and to quantify its pollutant emissions. The well-known benchmark process for hydrodealkylation (HDA) of toluene to produce benzene, revisited here in a multiobjective optimization way, is used to illustrate the approach for finding eco-friendly and cost-effective designs. Preliminary biobjective studies are carried out for eliminating redundant environmental objectives. The trade-off between economic and environmental objectives is illustrated through Pareto curves. In order to aid decision making among the various alternatives that can be generated after this step, a synthetic evaluation method, based on the so-called Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) (), has been first used. Another simple procedure named FUCA has also been implemented and shown its efficiency vs. TOPSIS. Two scenarios are studied; in the former, the goal is to find the best trade-off between economic and ecological aspects while the latter case aims at defining the best compromise between economic and more strict environmental impact

    Economic and environmental impacts of the energy source for the utility production system in the HDA process

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    The well-known benchmark process for hydrodealkylation of toluene (HDA) to produce benzene is revisited in a multi-objective approach for identifying environmentally friendly and cost-effective operation solutions. The paper begins with the presentation of the numerical tools used in this work, i.e., a multi-objective genetic algorithm and a Multiple Choice Decision Making procedure. Then, two studies related to the energy source involved in the utility production system (UPS), either fuel oil or natural gas, of the HDA process are carried out. In each case, a multi-objective optimization problem based on the minimization of the total annual cost of the process and of five environmental burdens, that are Global Warming Potential, Acidification Potential, Photochemical Ozone Creation Potential, Human Toxicity Potential and Eutrophication Potential, is solved and the best solution is identified by use of Multiple Choice Decision Making procedures. An assessment of the respective contribution of the HDA process and the UPS towards environmental impacts on the one hand, and of the environmental impacts generated by the main equipment items of the HDA process on the other hand is then performed to compare both solutions. This ‘‘gate-to-gate’’ environmental study is then enlarged by implementing a ‘‘cradle-togate’’ Life Cycle Assessment (LCA), for accounting of emission inventory and extraction. The use of a natural gas turbine, less economically efficient, turns out to be a more attractive alternative to meet the societal expectations concerning environment preservation and sustainable development

    Weighted Goal Programming and Penalty Functions: Whole-farm Planning Approach Under Risk

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    The paper presents multiple criteria approach to deal with risk in farmer’s decisions. Decision making process is organised in a framework of spreadsheet tool. It is supported by deterministic and stochastic mathematical programming techniques applying optimisation concept. Decision making process is conceptually divided into seven autonomous modules that are mutually linked up. Beside the common maximisation of expected income through linear programming it enables also reconstruction of current production practice. Income risk modelling is based on portfolio theory resting on expected value, variance (E,V) paradigm. Modules dealing with risk are therefore supported with quadratic and constrained quadratic programming. Non-parametric approach is utilised to estimate decision maker’s risk attitude. It is measured with coefficient of risk aversion, needed to maximise certainty equivalent for analysed farms. Multiple criteria paradigm is based on goal programming approach. In contribution focus is put on benefits and possible drawbacks of supporting weighted goal programming with penalty functions. Application of the tool is illustrated with three dairy farm cases. Obtained results confirm advantage of utilizing penalty function system. Beside greater positiveness it proves as useful approach for fine tuning of the model enabling imitation of farmer’s behaviour, which is due to his/her conservative nature not perfect or rational. Results confirm hypothesis that single criteria decision making, based on maximisation of expected income, might be biased and does not necessary lead to the best - achievable option for analysed farm.goal programming, risk modelling, risk aversion, production planning, Risk and Uncertainty,

    Reconfiguring an Irrigation Landscape to Improve Provision of Ecosystem Services

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    Over-allocation of fresh water resources to consumptive uses, coupled with recurring drought and the prospect of climate change, is compromising the stocks of natural capital in the world’s basins and reducing their ability to provide ecosystem services. To combat this, governments world wide are making significant investment in efforts to improve sharing of water between consumptive uses and the environment, with many investments centred on modernisation of inefficient irrigation delivery systems, and the purchase of water by government for environmental flows. In this study, spatial targeting was applied within a cost-benefit framework to reconfigure agricultural land use in an irrigation district to achieve a 20% reduction in agricultural water use to increase environmental flows and improve the provision of other ecosystem services. We demonstrate using spatial planning and optimisation models that a targeted land use reconfiguration policy approach could potentially increase the net present value of ecosystem services by up to AUS463.7m.Thisprovidesathresholdlevelofinvestmentthatwouldbejustifiedonthebasisofbenefitsthattheinvestmentproduces.Theincreaseinecosystemservicesincluderecovering61GLofwaterforenvironmentalflows,thesequestrationof10.6mtonnesofCO2e/yr,a13EC(?S/cm)reductioninriversalinity,andanoverall24463.7m. This provides a threshold level of investment that would be justified on the basis of benefits that the investment produces. The increase in ecosystem services include recovering 61 GL of water for environmental flows, the sequestration of 10.6m tonnes of CO2-e/yr, a 13 EC (?S/cm) reduction in river salinity, and an overall 24% increase in the value of agriculture. Without a targeted approach to planning, a 20% reduction in water for irrigation could result in the loss of AUS68.7m in economic returns to agriculture which may be only marginally offset by the increased value of ecosystem services resulting from the return of 61 GL of water to the environment.landscape planning, geographic information systems, cost-benefit analysis, irrigation, climate change, water management, spatial targeting, environmental valuation

    A comparative study of multiple-criteria decision-making methods under stochastic inputs

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    This paper presents an application and extension of multiple-criteria decision-making (MCDM) methods to account for stochastic input variables. More in particular, a comparative study is carried out among well-known and widely-applied methods in MCDM, when applied to the reference problem of the selection of wind turbine support structures for a given deployment location. Along with data from industrial experts, six deterministic MCDM methods are studied, so as to determine the best alternative among the available options, assessed against selected criteria with a view toward assigning confidence levels to each option. Following an overview of the literature around MCDM problems, the best practice implementation of each method is presented aiming to assist stakeholders and decision-makers to support decisions in real-world applications, where many and often conflicting criteria are present within uncertain environments. The outcomes of this research highlight that more sophisticated methods, such as technique for the order of preference by similarity to the ideal solution (TOPSIS) and Preference Ranking Organization method for enrichment evaluation (PROMETHEE), better predict the optimum design alternative

    How can we know if EU cohesion policy is successful? Integrating micro and macro approaches to the evaluation of Structural Funds

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    In this paper we describe an integrated approach for assessing the general economic effectiveness, efficiency and impact of public policy actions for large investment programs of the kind implemented over the past fifteen years in EU-aided Structural Fund programmes. Far from being rigid, our modelling philosophy includes both formal tools designed to assess all relevant effects, as well as informal (intuitive) elements to allow for flexible policy design and evaluation. When setting up an integrated micro-macro (IMM) model we are trying to over-come two major shortcomings in actual policy design and analysis: Firstly, to bridge the gap between the scientific requirements of model-based decision making and evaluation and the practical requirement for flexible and easy to use decision support tools that are well suited for day-to-day application. Secondly, to address the observed discrepancy in policy analysis between programme monitoring and evaluation realized at a highly aggregate level using quantitative macromodels (the so called “top down” approach) and the highly disaggregated approach to project evaluation, marked as micro- or “bottom up”-approaches.

    Improved resource efficiency and cascading utilisation of renewable materials

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    In light of various environmental problems and challenges concerning resource allocation, the utilisation of renewable resources is increasingly important for the efficient use of raw materials. Therefore, cascading utilisation (i.e., the multiple material utilisations of renewable resources prior to their conversion into energy) and approaches that aim to further increase resource efficiency (e.g., the utilisation of by-products) can be considered guiding principles. This paper therefore introduces the Special Volume “Improved Resource Efficiency and Cascading Utilisation of Renewable Materials”. Because both research aspects, resource efficiency and cascading utilisation, belong to several disciplines, the Special Volume adopts an interdisciplinary perspective and presents 16 articles, which can be divided into four subjects: Innovative Materials based on Renewable Resources and their Impact on Sustainability and Resource Efficiency, Quantitative Models for the Integrated Optimisation of Production and Distribution in Networks for Renewable Resources, Information Technology-based Collaboration in Value Generating Networks for Renewable Resources, and Consumer Behaviour towards Eco-friendly Products. The interdisciplinary perspective allows a comprehensive overview of current research on resource efficiency, which is supplemented with 15 book reviews showing the extent to which textbooks of selected disciplines already refer to resource efficiency. This introductory article highlights the relevance of the four subjects, presents summaries of all papers, and discusses future research directions. The overall contribution of the Special Volume is that it bridges the resource efficiency research of selected disciplines and that it presents several approaches for more environmentally sound production and consumption

    Robust optimisation of urban drought security for an uncertain climate

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    Abstract Recent experience with drought and a shifting climate has highlighted the vulnerability of urban water supplies to “running out of water” in Perth, south-east Queensland, Sydney, Melbourne and Adelaide and has triggered major investment in water source infrastructure which ultimately will run into tens of billions of dollars. With the prospect of continuing population growth in major cities, the provision of acceptable drought security will become more pressing particularly if the future climate becomes drier. Decision makers need to deal with significant uncertainty about future climate and population. In particular the science of climate change is such that the accuracy of model predictions of future climate is limited by fundamental irreducible uncertainties. It would be unwise to unduly rely on projections made by climate models and prudent to favour solutions that are robust across a range of possible climate futures. This study presents and demonstrates a methodology that addresses the problem of finding “good” solutions for urban bulk water systems in the presence of deep uncertainty about future climate. The methodology involves three key steps: 1) Build a simulation model of the bulk water system; 2) Construct replicates of future climate that reproduce natural variability seen in the instrumental record and that reflect a plausible range of future climates; and 3) Use multi-objective optimisation to efficiently search through potentially trillions of solutions to identify a set of “good” solutions that optimally trade-off expected performance against robustness or sensitivity of performance over the range of future climates. A case study based on the Lower Hunter in New South Wales demonstrates the methodology. It is important to note that the case study does not consider the full suite of options and objectives; preliminary information on plausible options has been generalised for demonstration purposes and therefore its results should only be used in the context of evaluating the methodology. “Dry” and “wet” climate scenarios that represent the likely span of climate in 2070 based on the A1F1 emissions scenario were constructed. Using the WATHNET5 model, a simulation model of the Lower Hunter was constructed and validated. The search for “good” solutions was conducted by minimizing two criteria, 1) the expected present worth cost of capital and operational costs and social costs due to restrictions and emergency rationing, and 2) the difference in present worth cost between the “dry” and “wet” 2070 climate scenarios. The constraint was imposed that solutions must be able to supply (reduced) demand in the worst drought. Two demand scenarios were considered, “1.28 x current demand” representing expected consumption in 2060 and “2 x current demand” representing a highly stressed system. The optimisation considered a representative range of options including desalination, new surface water sources, demand substitution using rainwater tanks, drought contingency measures and operating rules. It was found the sensitivity of solutions to uncertainty about future climate varied considerably. For the “1.28 x demand” scenario there was limited sensitivity to the climate scenarios resulting in a narrow range of trade-offs. In contrast, for the “2 x demand” scenario, the trade-off between expected present worth cost and robustness was considerable. The main policy implication is that (possibly large) uncertainty about future climate may not necessarily produce significantly different performance trajectories. The sensitivity is determined not only by differences between climate scenarios but also by other external stresses imposed on the system such as population growth and by constraints on the available options to secure the system against drought. Recent experience with drought and a shifting climate has highlighted the vulnerability of urban water supplies to “running out of water” in Perth, south-east Queensland, Sydney, Melbourne and Adelaide and has triggered major investment in water source infrastructure which ultimately will run into tens of billions of dollars. With the prospect of continuing population growth in major cities, the provision of acceptable drought security will become more pressing particularly if the future climate becomes drier. Decision makers need to deal with significant uncertainty about future climate and population. In particular the science of climate change is such that the accuracy of model predictions of future climate is limited by fundamental irreducible uncertainties. It would be unwise to unduly rely on projections made by climate models and prudent to favour solutions that are robust across a range of possible climate futures. This study presents and demonstrates a methodology that addresses the problem of finding “good” solutions for urban bulk water systems in the presence of deep uncertainty about future climate. The methodology involves three key steps: 1) Build a simulation model of the bulk water system; 2) Construct replicates of future climate that reproduce natural variability seen in the instrumental record and that reflect a plausible range of future climates; and 3) Use multi-objective optimisation to efficiently search through potentially trillions of solutions to identify a set of “good” solutions that optimally trade-off expected performance against robustness or sensitivity of performance over the range of future climates. A case study based on the Lower Hunter in New South Wales demonstrates the methodology. It is important to note that the case study does not consider the full suite of options and objectives; preliminary information on plausible options has been generalised for demonstration purposes and therefore its results should only be used in the context of evaluating the methodology. “Dry” and “wet” climate scenarios that represent the likely span of climate in 2070 based on the A1F1 emissions scenario were constructed. Using the WATHNET5 model, a simulation model of the Lower Hunter was constructed and validated. The search for “good” solutions was conducted by minimizing two criteria, 1) the expected present worth cost of capital and operational costs and social costs due to restrictions and emergency rationing, and 2) the difference in present worth cost between the “dry” and “wet” 2070 climate scenarios. The constraint was imposed that solutions must be able to supply (reduced) demand in the worst drought. Two demand scenarios were considered, “1.28 x current demand” representing expected consumption in 2060 and “2 x current demand” representing a highly stressed system. The optimisation considered a representative range of options including desalination, new surface water sources, demand substitution using rainwater tanks, drought contingency measures and operating rules. It was found the sensitivity of solutions to uncertainty about future climate varied considerably. For the “1.28 x demand” scenario there was limited sensitivity to the climate scenarios resulting in a narrow range of trade-offs. In contrast, for the “2 x demand” scenario, the trade-off between expected present worth cost and robustness was considerable. The main policy implication is that (possibly large) uncertainty about future climate may not necessarily produce significantly different performance trajectories. The sensitivity is determined not only by differences between climate scenarios but also by other external stresses imposed on the system such as population growth and by constraints on the available options to secure the system against drought. Please cite this report as: Mortazavi, M, Kuczera, G, Kiem, AS, Henley, B, Berghout, B,Turner, E, 2013 Robust optimisation of urban drought security for an uncertain climate. National Climate Change Adaptation Research Facility, Gold Coast, pp. 74

    Evaluation of an Australian Solar Community : Implications for Education and Training

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    1.1 Background What is renewable energy education and training? A cursory exploration of the International Solar Energy Society website (www.ises.org) reveals numerous references to education and training, referring collectively to concepts of the transfer and exchange of information and good practices, awareness raising and skills development. The purposes of such education and training relate to changing policy, stimulating industry, improving quality control and promoting the wider use of renewable energy sources. The primary objective appears to be to accelerate a transition to a better world for everyone (ISEE), as the greater use of renewable energy is seen as key to climate recovery; world poverty alleviation; advances in energy security, access and equality; improved human and environmental health; and a stabilized society. The Solar Cities project – Habitats of Tomorrow – aims at promoting the greater use of renewable energy within the context of long term planning for sustainable urban development. The focus is on cities or communities as complete systems; each one a unique laboratory allowing for the study of urban sustainability within the context of a low carbon lifestyle. The purpose of this paper is to report on an evaluation of a Solar Community in Australia, focusing specifically on the implications (i) for our understandings and practices in renewable energy education and training and (ii) for sustainability outcomes. 1.2 Methodology The physical context is a residential Ecovillage (a Solar Community) in sub-tropical Queensland, Australia (latitude 28o south). An extensive Architectural and Landscape Code (A&LC) ‘premised on the interconnectedness of all things’ and embracing ‘both local and global concerns’ governs the design and construction of housing in the estate: all houses are constructed off-ground (i.e. on stumps or stilts) and incorporate a hybrid approach to the building envelope (mixed use of thermal mass and light-weight materials). Passive solar design, gas boosted solar water heaters and a minimum 1kWp photovoltaic system (grid connected) are all mandatory, whilst high energy use appliances such as air conditioners and clothes driers are not permitted. Eight families participated in an extended case study that encompassed both quantitative and qualitative approaches to better understand sustainable housing (perceived as a single complex technology) through its phases of design, construction and occupation. 1.3 Results The results revealed that the level of sustainability (i.e. the performance outcomes in terms of a low-carbon lifestyle) was impacted on by numerous ‘players’ in the supply chain, such as architects, engineers and subcontractors, the housing market, the developer, product manufacturers / suppliers / installers and regulators. Three key factors were complicit in the level of success: (i) systems thinking; (ii) informed decision making; and (iii) environmental ethics and business practices. 1.4 Discussion The experiences of these families bring into question our understandings and practices with regard to education and training. Whilst increasing and transferring knowledge and skills is essential, the results appear to indicate that there is a strong need for expanding our education efforts to incorporate foundational skills in complex systems and decision making processes, combined with an understanding of how our individual and collective values and beliefs impact on these systems and processes
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