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© 2016 Elsevier Ltd Smart water metering (SWM) introduces new opportunities to engage householders about water use based on detailed information. Water utilities must decide how to embrace these opportunities, but remain hesitant due to limited available experience and knowledge, which risks delaying the benefits of involving householders more fully in SWM and more sustainable water consumption. An implementation framework is developed outlining the key strategic, practical and evaluative elements in decision-making for detailed feedback programs by drawing on the literature and first-hand experiences of two feedback trials involving SWM. Existing approaches are reviewed and recommendations are provided to advance more well-considered approaches and realise benefits regarding sustainable water use.

Phosphorus (P) is an essential fertilizer for agricultural production but is also a potent aquatic pollutant. Current P management fails to adequately address both the issue of food security due to P scarcity and P pollution threats to water bodies. As centers of food consumption and waste production, cities transport and store much P and thus provide important opportunities to improve P management. Substance flow analysis (SFA) is often used to understand urban P cycling and to identify inefficiencies that may be improved on. However, SFAs typically do not examine the factors that drive observed P dynamics. Understanding the social, ecological, and technological context of P stocks and flows is necessary to link urban P management to existing urban priorities and to select local management options that minimize tradeoffs and maximize synergies across priorities. Here, we review P SFA studies in 18 cities, focusing on gaps in the knowledge required to implement P management solutions. We develop a framework to systemically explore the full suite of factors that drive P dynamics in urban systems. By using this framework, scientists and managers can build a better understanding of the drivers of P cycling and improve our ability to address unsustainable P use and waste.

This paper categorises different concentrating solar power (CSP) hybrid options into light, medium and strong hybrids and discusses the combination of CSP with coal, natural gas, biomass and waste materials, geothermal, and wind. The degree of hybridisation depends on the interconnection of the plant components. Light hybrids create only limited synergies, such as the joint use of a substation, and their cost reduction potential is therefore limited, while strong hybrids share major plant components, such as steam turbine and condenser, and can better match their energy output with electricity pricing. The hybridisation options for CSP with different energy sources are plentiful ranging from feedwater heating, reheat steam, live steam to steam superheating with some options better suited for a specific energy source combination than others. The synergies created in hybrid plants can lead to cost reductions of 50%, better energy dispatchability as well as revenue maximisation. Several CSP hybrid studies exist for coal, natural gas and biomass but these are often investigating a specific hybrid concept. This paper considers several options at a higher level and also includes geothermal and wind which is novel. While the paper focuses on Australia the approach taken and concepts discussed are transferable to other countries.

Australia's extensive solar resource is underexploited especially in the CSP (concentrating solar power) arena because of the high investment and lack of stable investment incentives. CSP hybrid plants provide an option to improve returns from CSP installations because of lower specific investment. This paper investigates the generation potential and most prospective regions for 5–60 MWe CSP hybrids using forestry residues, bagasse, stubble, wood waste and refuse derived fuels in locations with a direct normal irradiance >18 MJ/m2/day. Different plant efficiencies are used to identify the overall electricity potential for single and multiple feedstocks systems. The EfB (energy from biomass) or EfW (energy from waste) components of the hybrid plants considered are assumed to allow base load operation with the CSP components providing additional capacity during the day. The total CSP-EfB & EfW hybrid potential in Australia, within 50 km of existing transmission and distribution infrastructure, is 7000 MWe which would require an investment of AU$ 39.5b to annually generate 33.5 TWh. This is equivalent to 12.8% of all electricity generated in 2008–2009 or 74% of Australia's 2020 renewable energy target. The CO2 abatement potential of CSP-EfB & EfW hybrids is up to 27 Mt or 4.8% of all 2009–10 CO2 emissions.

Concentrating solar power (CSP)-biomass hybrids plants are becoming increasingly interesting as a low cost option to provide dispatchable renewable energy since the first reference plant commenced operation late 2012, 22.5MWe Termosolar Borges in Spain. The development of such project is a complex task with not only one but two energy sources required to make the project successful. The availability of several studies but only one reference plant worldwide is proof of that. This paper investigates the hybridisation of a biomass power plant with a molten salt solar tower system. The benefit of this combination is a high cycle efficiency as both the steam generators can provide steam at 525 °C and 120 bar to the steam turbine. A case study approach is used to provide technical, economic and environmental benefits of a 30MWe CSP-biomass plant with 3 h thermal storage in Griffith, New South Wales. At this site such a plant could provide annually 160,300MWh of electricity with an annual average electricity price of AU$155/MWh. Compared to a standalone CSP plant with 15 h of thermal storage the hybrid plant investment is 43% lower, providing a possibility to fast-track CSP implementation in countries where CSP is struggling to enter the market due to low wholesale electricity prices, such as Australia.

It is well understood that the cost of concentrating solar power (CSP) will need to decrease quickly to ensure competitiveness with photovoltaic (PV) systems and other forms of power generation. Research and development on CSP plant components is crucial in order to reduce costs but is typically time consuming. New CSP plant concepts combining proven technologies with CSP represent another option that can be implemented quickly. This paper investigates the use of several biomass materials to externally superheat steam in conventional parabolic trough plants. Currently, parabolic trough plants are easiest to finance and external steam superheating can overcome the lower efficiencies compared to other CSP technologies. Seven scenarios, each air and water cooled, with steam parameters ranging from 380 °C at 100 bar to 540 °C at 130 bar have been modeled, and the results presented here are based on a 50 MWe plant with 7.5 h molten salt thermal storage. Our results show that the peak solar to electricity net efficiency increases up to 10.5% while the specific investment can decrease immediately from AU$8.2m/MWe to AU$6.3m/MWe, a 23.5% reduction. That is significant considering the expected 17–40% CSP cost reduction targets by the end of this decade. The modeling shows that even major fuel and water price changes are significantly less relevant than small changes in the agreed electricity purchase price. The technical, economic and environmental analysis reveals that external superheating with biomass can provide significant benefits, is able to use a variety of fuels and despite a limited global market, could immediately enable the implementation of several hundred MWe of CSP capacity at lower cost.

Recently, the first concentrating solar power–biomass hybrid power plant commenced operation in Spain and the combination of both energy sources is promising to lower plant investment. This assessment investigates 17 different concentrating solar power–biomass hybrid configurations in regards their technical, economic and environmental performance. The integration of molten salt thermal storage is considered for the best performing hybrid configuration. While thermal storage can increase plant output significantly even 7 h full-load thermal storage plants would generate the majority of the electricity, 70%, from the biomass resource. Only mature technologies with references >5 MWe are considered in this assessment to ensure that the scenarios are bankable. The concentrating solar power technologies selected are parabolic trough, Fresnel and solar tower while the biomass systems include grate, fluidised bed and gasification with producer gas use in a boiler. A case study approach based on the annual availability of 100,000 t of wood biomass is taken to compare the different plant configurations but the results are transferable to other locations when updating site and cost conditions. Results show that solar tower–biomass hybrids reach the highest net cycle efficiency, 32.9%, but that Fresnel-biomass hybrids have the lowest specific investment, AU$ 4.5 m/MWe. The investment difference between the 17 scenarios is with up to 31% significant. Based on the annual electricity generation CSP–biomass hybrids have an up to 69% lower investment compared to standalone concentrating solar power systems. The scenario with the best technical performance, being solar tower and gasification, is at this point in time not necessarily the best commercial choice, being Fresnel and fluidised bed, as the lower Fresnel investment outweighs the additional electricity generation potential solar towers offer. However, other scenarios with different benefits rank closely.

This assessment aims to identify the most suitable concentrated solar power (CSP) technologies to hybridize with Rankine cycle power plants using conventional fuels, such as gas and coal, as well as non-conventional fuels, namely biomass and waste materials. The results derive from quantitative data, such as literature, industry information and own calculations, as well as qualitative data from an expert workshop. To incorporate the variety of technology criteria, quantitative and qualitative data the Analytical Hierarchy Process (AHP) is used as the multi-criteria decision making (MCDM) tool. Only CSP technologies able to directly or indirectly generate steam are compared in regards to feasibility, risk, environmental impact and Levelised Cost of Electricity (LCOE). Different sub-criteria are chosen to consider the most relevant aspects. The study focuses on the suitability of CSP technologies for hybridisation and results obtained are reality checked by comparison with plants already being built/under construction. The results of this assessment are time dependant and may change with new CSP technologies maturing and prices decreasing in the future.Key findings of this assessment show that Fresnel systems seem to be the best technology for feedwater preheating, cold reheat steam and

Global phosphorus scarcity is likely to threaten the world's ability to produce food in the future if concerted efforts to ensure long-term phosphorus availability and accessibility and to use phosphorus more sustainably in the food system are not taken by policy makers, scientists and industry. Each country is vulnerable to phosphorus scarcity in different ways due to different characteristics of the national food system. However numerous opportunities exist to steer countries on a more sustainable trajectory to buffer food systems against such risks. A country-level phosphorus flow analysis can aid the identification of current inefficiencies, potential points for phosphorus recovery, reduction in losses and facilitate prioritisation of policy measures. This paper presents the findings and implications of a phosphorus flow analysis for Australia. The analysis found that despite being a net food exporter (predominantly to Asia), Australia is a net phosphorus importer (80. kt/a of P) to replenish naturally phosphorus-deficient soils and support a phosphorus-intensive agricultural and livestock export sector. Simultaneously, there is a net phosphorus deficiency from the Australian food system (106. kt/a of P) due to substantial losses and inefficiencies from mine to field to fork. The livestock sector represents over 60% of Australia's phosphorus demand due to fertilised pastures and animal feed. The manure produced by the 211 million head of livestock in Australia alone contains 60 times more phosphorus than the food consumed by the entire Australian population. Key opportunities to increase the resilience of the Australian food system include: increasing manure reuse, phosphorus use efficiency in fertilised pastures, investigate phosphorus recovery from phosphogypsum waste stockpiles and investigating more phosphorus-efficient food and agricultural commodities-particularly to reduce exported and wasted phosphorus whilst maintaining or enhancing productivity. © 2013 Elsevier Ltd.

This paper investigates the practical and theoretical advantages of collaborative stakeholder (CSD) dialogue over adversarial processes in facilitating better transport policy choices. CSD is an emergent governance procedure that is increasingly advocated by practitioners and researchers as a practical means of counterbalancing the asymmetry of interests in public policy making. In CSD, participants that represent the full diversity of interdependent organised interests in the issue at stake engage in collaborative dialogue to find a consensus on the way forward. In order to improve the process and application of CSD in transport it is important to systematically compare this procedure to the conventional adversarial style of stakeholder interaction in the transport policy process. To do so this paper builds on a governance framework that allows the comparison of the collaborative and adversarial pathways with regards to their potential to facilitate better transport policy choices. The paper concludes by proposing CSD as a tool to de-politicise stakeholder discussions and so enable a shift away from the traditionally narrow priority of transport policy making to facilitate economic growth to a broader focus that better integrates environmental, social and economic considerations. It also concludes that CSD is most appropriate in problem situations with high levels of conflict between competing stakeholder groups that all have influence. © 2012 Elsevier Ltd.

We show that nuclear C ∗ -algebras have a refined version of the completely positive approximation property, in which the maps that approximately factorize through finite dimensional algebras are convex combinations of order zero maps. We use this to show that a separable nuclear C ∗ -algebra A which is closely contained in a C ∗ -algebra B embeds into B .

Food production requires application of fertilizers containing phosphorus, nitrogen and potassium on agricultural fields in order to sustain crop yields. However modern agriculture is dependent on phosphorus derived from phosphate rock, which is a non-renewable resource and current global reserves may be depleted in 50–100 years. While phosphorus demand is projected to increase, the expected global peak in phosphorus production is predicted to occur around 2030. The exact timing of peak phosphorus production might be disputed, however it is widely acknowledged within the fertilizer industry that the quality of remaining phosphate rock is decreasing and production costs are increasing. Yet future access to phosphorus receives little or no international attention. This paper puts forward the case for including long-term phosphorus scarcity on the priority agenda for global food security. Opportunities for recovering phosphorus and reducing demand are also addressed together with institutional challenges.

We consider normalizers of an irreducible inclusion $N\subseteq M$ of $\mathrm{II}_1$ factors. In the infinite index setting an inclusion $uNu^*\subseteq N$ can be strict, forcing us to also investigate the semigroup of one-sided normalizers. We relate these normalizers of $N$ in $M$ to projections in the basic construction and show that every trace one projection in the relative commutant $N'\cap < M,e_N>$ is of the form $u^*e_Nu$ for some unitary $u\in M$ with $uNu^*\subseteq N$. This enables us to identify the normalizers and the algebras they generate in several situations. In particular each normalizer of a tensor product of irreducible subfactors is a tensor product of normalizers modulo a unitary. We also examine normalizers of irreducible subfactors arising from subgroup--group inclusions $H\subseteq G$. Here the normalizers are the normalizing group elements modulo a unitary from $L(H)$. We are also able to identify the finite trace $L(H)$-bimodules in $\ell^2(G)$ as double cosets which are also finite unions of left cosets., 33 Pages