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• Calculation of product circularity and global warming indicators. • Evaluation of end-of-life management solutions to slow and close resource loops. • Chemical recycling has the greater circularity and low-impact potential. • Thermal recycling has the lower circularity and higher carbon footprint. • Higher circularity does not always lead to carbon savings. It is estimated that 570 Mt of blade waste, whose management is complex and expensive, will be generated by 2030 in the European Union alone. Accordingly, alternative blade waste management techniques are being investigated to optimize material recovery. This study evaluates the correlation between the circular economy performance and the carbon footprint of seven end-of-life management solutions for wind turbine blades: repurposing, grinding, solvolysis, pyrolysis, co-processing in cement kilns, incineration with energy recovery and landfilling. The circular economy performance is analyzed through the calculation of the product circularity indicator, while the carbon footprint is determined through life cycle assessment, using the global warming indicator and considering the management of three blades from cradle-to-gate as functional unit. As the performance of solvolysis and pyrolysis recycling is expected to change in the future, a sensitivity analysis is also carried out to evaluate the variability of the results by changing their process efficiency and the quality of the recovered materials. The results indicate that blade recycling through solvolysis is the most circular (0.47–0.77) and low-carbon (225–503 CO 2 eq.) solution overall. Blade repurposing, grinding and cement co-processing have a similar circularity (0.52–0.55) and a global warming impact ranging from 499 t CO 2 eq. to 615 t CO 2 eq. Although the circularity of pyrolysis is 59% (0.35) to 118% (0.48) greater than the circularity of incineration and landfilling (0.22), its carbon footprint can range from 566 t CO 2 eq. to 744 t CO 2 eq, which could be up to 19% higher than the carbon footprint of these linear EoL management alternatives (623 t CO 2). Based on these findings, proposals for sustainable industrial innovation and methodological recommendations for the development of integrated circularity and sustainability studies are proposed. [ABSTRACT FROM AUTHOR]

Many higher education institutions have started to develop academic curricula, research capacity and outreach activities related to circular economy. However, little is known yet on how to apply circular economy thinking to sustainable campus management. In an attempt to address this gap, this paper proposes a methodological framework and guidance to help universities develop a circular economy strategy aimed at improving resource efficiency and environmental sustainability of their campus operations. The approach is compatible with sustainability management frameworks as it follows the well-known iterative process of planning, doing, checking and improving. The framework involves three main steps: analysis of current situation with respect to circular economy within the organisation; stakeholder engagement to get a buy-in and inform the development of a circular economy strategy; and implementation of the strategy following the guidelines provided within the framework. Application of the framework is illustrated through a case of the University of Manchester, demonstrating how circular economy principles can be used to benchmark existing sustainability policies and action plans. The paper also shows how engaging key stakeholders can be used to identify challenges and opportunities for embedding circular economy thinking into the university's sustainability management systems. The proposed framework and the guidelines for implementation of circular economy thinking are generic and can be applied by any institution across the higher education sector. Image 1 • There is a lack of knowledge on how to implement circular economy in universities. • A simple but powerful framework is proposed to guide institutions in that process. • Application of the framework is illustrated through a real case of a large UK university. • Challenges and opportunities for CE are discussed based on stakeholder interviews. • Guidelines are provided for the development and implementation of a CE strategy. [ABSTRACT FROM AUTHOR]

Abstract Various frameworks have been developed to guide organisations in embedding circular economy principles in their strategy and operational practice. However, there is a lack of studies analysing practical implementation of circular economy thinking in the higher education sector. Higher education institutions are strategic agents in supporting sustainable development through teaching, research and social outreach activities. They also represent a source of environmental impacts due to significant resource consumption and waste generation. This paper presents the first comprehensive study showing how higher education institutions can use an action-led step-by-step approach to build a business case and implement circular economy thinking in practice. The University of Manchester is used as an illustrative example of a large higher education institution. First, a background analysis and semi-structured interviews were carried out to determine the scope of the university's current sustainability policies and the ability of the management systems to respond to circular economy challenges. This was followed by stakeholder workshops to identify gaps and opportunities for building a business case for implementation of a circular economy. Finally, a critical assessment of the outcomes was carried out to identify further research needs for implementation of a circular economy in higher education institutions. Although focused on the higher education sector, the proposed action-led approach can be used by any organisation in the service sector looking to build more circular and sustainable business models. [ABSTRACT FROM AUTHOR]

Abstract The literature on baby diapers has so far focused on environmental implications of using cloth instead of disposable products, utilising bio-materials or enabling recycling and composting. However, no study to date has examined the life cycle costs and eco-efficiency implications of cleaner production of disposable diapers. Therefore, this paper sets out to evaluate the economic and environmental savings that could be achieved by eco-design and cleaner production of disposable baby diapers. This involves the use of an optimised absorbent core and innovative bonding technologies to replace gluing systems in diaper manufacturing. The analysis is carried out at different production and consumption scales: a single production platform, a whole industrial plant, a country and the European Union (EU). A cradle-to-grave life cycle costing demonstrates that the novel design and manufacture of the so-called "glueless" diapers reduce costs by 11% compared to the conventional product. This is equivalent to saving €250 million at the EU level. Likewise, the eco-efficiency analysis shows that the glueless diapers are 7%–170% more eco-efficient (€/impact) than the standard diapers, depending on the environmental impact considered. Still, eco-design and cleaner production will not help to resolve the underlying critical issue of the linear material consumption and waste generation associated with the use of disposable baby diapers. Further industrial efforts must concentrate on finding solutions to facilitate implementation of circular economy principles for these products. This calls for the development of new circular business models as discussed in the paper. Graphical abstract Image 1 Highlights • New diapers are overall 32% more eco-efficient (€/impact) than the standard type. • Cleaner production of diapers reduces the life cycle costs by 11%. • At the EU level, this corresponds to an annual saving in costs of €250 million. • In addition, 192 kt materials and wastes and 184 kt of CO 2 eq. are saved annually. • Still, implementation of a circular economy is critical for the diapers industry. [ABSTRACT FROM AUTHOR]

Abstract The annual market demand for disposable baby diapers exceeds 20 billion units (690 kt) in the European Union (EU). Almost 40,000 disposable diapers are used every minute, producing 1.3 t/min (dry weight) of waste. Based on the estimates in this work, this requires 90.3 PJ of primary energy and emits 2.7 Mt CO 2 eq. annually. In an attempt to reduce resource, waste and environmental impacts associated with diapers, this paper focuses on novel design and manufacture of disposable baby diapers. This involves using optimised absorbent core and novel bonding technologies to replace conventional gluing of diaper materials. Life cycle assessment has been performed to compare the environmental performance of these new diapers, here termed "glueless", with standard designs. The annual resource consumption and environmental impacts of glueless diapers have been estimated at different production levels: a single production platform, an industrial plant, a country (Italy) and the EU, taking into account different production volumes, electricity mixes and waste management options. Different market penetration scenarios have been considered to determine potential environmental implications at the EU level by 2020. The results reveal that glueless diapers reduce the consumption of raw materials by 23% (9.2 g/diaper), primary energy demand by 25% (752 kJ/diaper) and global warming potential by 10% (10.4 g CO 2 eq./diaper) compared to the standard diapers. They also have more than 50% lower eutrophication, ozone depletion and human and eco-toxicity. Up to 16 PJ primary energy and 191,000 t CO 2 eq. would be saved annually in the EU by using glueless diapers. The cumulative savings would amount to 47 PJ and 566,000 t CO 2 eq. by 2020. The annual consumption of raw materials at the EU level would be reduced by 196,000 t with cumulative savings of up to 584,000 t by 2020, also reducing the equivalent amount of waste from the disposal of diapers. Consequently, glueless diapers can contribute to meeting the energy, climate and resource efficiency goals specified in the EU 2020 strategy. Graphical abstract Image 1 Highlights • Novel design and manufacture of "glueless" disposable baby diapers is considered. • Glueless diapers save 23% of materials and 25% of energy relative to standard type. • Most life cycle impacts are reduced by >50% and global warming potential by 10%. • Up to 584,000 t of waste and 566,000 t of CO 2 eq. can be saved by 2020. • Glueless diapers can help meet the EU energy, resource and climate change targets. [ABSTRACT FROM AUTHOR]

Abstract The sustainability benefits of using solar cookers in developing countries have been analysed widely in the literature. However, the sustainability potential of solar cookers in developed economies has not been explored yet, which is the topic of this paper. Three types of solar cooker – box, panel and parabolic – were built as part of this research, using mostly (>70%) reused household materials. Their life cycle environmental and economic performance was analysed and compared to conventional microwaves. The results were first considered at the level of individual cookers and then scaled up to the levels of a city, region and country, considering a conservative (10%) uptake of solar cookers in substitution of microwaves. The contribution of home-made solar cookers to a circular economy and their social sustainability were also analysed. Spain was used as an illustrative example to demonstrate the potential sustainability benefits of using solar cookers in developed countries. The results suggest that, in comparison with microwaves, they could reduce annual life cycle costs by up to 40% and environmental impacts by up to 65%, including greenhouse gas emissions. At the national level, 42,600 t of CO 2 eq. would be avoided annually while the consumption of primary energy would be reduced by 860 TJ. Furthermore, the electricity consumption would decrease by 67 GWh/yr and 4200 t/yr of household waste would be avoided. If solar cookers were built entirely by reusing household materials, up to €23.2 million could be saved per year. Finally, the development of craft activities to build and repair the cookers can help people to engage socially and reduce stress, thus enhancing their social wellbeing. It can also increase people's awareness of a more sustainable use of resources. Therefore, home-made solar cookers represent a promising opportunity to motivate behavioural changes towards a circular economy and sustainability in developed countries. Graphical abstract Unlabelled Image Highlights • The benefits of using home-made solar cookers instead of microwaves are evaluated. • GHG emissions and waste generation can be reduced by 42.6 kt and 4.2 kt annually. • Around 67 GWh of electricity and €23.2 million can be saved each year. • Social engagement in building and using solar cookers can enhance social wellbeing. • They can motivate behavioural changes towards circular economy and sustainability. [ABSTRACT FROM AUTHOR]

Modern lifestyles have popularised the use of food containers, also known as food savers or Tupperware. However, their environmental impacts are currently unknown. To fill this knowledge gap, this paper presents the first comprehensive assessment of the life cycle environmental sustainability of reusable plastic and glass food savers and evaluates different options for improvements, focusing on European conditions. Taking a cradle-to-grave approach, the paper considers twelve environmental impacts, including global warming potential (GWP), acidification, eutrophication, human and ecotoxicities. The results suggest that, for example, the total GWP of using both types of food saver in the European Union (EU) amounts to 653 kt CO 2 eq./year, equivalent to the annual greenhouse gas emissions of Bermuda. The use stage is the main contributor to the impacts (>40%), related to the washing of containers. Glass food savers have 12%–64% higher impacts than the plastic and should have up to 3.5 times greater lifespan to match the environmental footprint of plastic containers. Three improvement scenarios have been considered at the EU level for the year 2020: low-carbon electricity mix; implementation of the EU eco-design regulation for dishwashers; and adoption of more resource-efficient hand dishwashing techniques. The results suggest that the implementation of all three improvement options would reduce the impacts by 12%–47%. The option with the greatest potential for reducing the impacts (12%–27%) is improved hand dishwashing to reduce the amount of water, energy and detergents used. Thus, policy makers and manufacturers should devise strategies to raise awareness and guide consumers in adopting these techniques with the aim of reducing the environmental impacts associated with reusable food savers used by millions of people worldwide. [ABSTRACT FROM AUTHOR]

More than 130 million microwaves are affected by European Union (EU) legislation which is aimed at reducing the consumption of electricity in the standby mode (‘Standby Regulation’) and at more sustainable management of end-of-life electrical and electronic waste (‘WEEE Directive’). While legislation focuses on these two life cycle stages, there is little information on the environmental impacts of the entire life cycle of microwaves. To address this gap, this paper presents a comprehensive life cycle assessment of microwaves and assesses the environmental implications of the Standby Regulation and the WEEE Directive at the EU level. The impacts are first considered at the level of individual appliances and then at the EU level, with the aim of evaluating the potential environmental implications of the full implementation of the above two EU regulations by 2020. The effects of the electricity decarbonisation and the expected increase in the number of microwaves in use have also been considered. The results suggest that implementation of the EU regulation by 2020 will reduce the environmental impacts considered by 4%–9% compared to the current situation. The majority of these reductions is due to the Standby Regulation, with the contribution of the WEEE Directive being small (~ 0.3%). However, the expected decarbonisation of electricity will result in much higher reductions (6%–24%) for most impact categories. The results also show that the materials used to manufacture the microwaves, the manufacturing process and end-of-life disposal are environmental hot-spots for several impacts, including depletion of abiotic elements. Therefore, efforts to reduce the environmental impacts of a future electricity mix should be combined with the development of specific eco-design regulations for microwaves that stipulate optimisation of resource consumption. Possible future trends, such as shorter lifetimes and limited availability of some resources, make the development of such product regulations more critical. [ABSTRACT FROM AUTHOR]

The circular economy (CE) is essential for decoupling economic growth from resource consumption and environmental impacts. However, effective implementation requires a systemic change across supply chains, involving both technological and nontechnological innovations. Frameworks are beginning to emerge to foster CE thinking in organizations. However, literature review carried out as part of this research has revealed gaps in their ability to fulfil CE requirements. Furthermore, few frameworks provide support on how CE requirements may be implemented. To address these issues, this article presents a new framework, BECE (backcasting and eco-design for the circular economy), to ensure that businesses can implement CE requirements more readily. BECE empowers organizations to tackle the CE holistically by embedding the concept into corporate decision making and by bringing operational and systems thinking together, thus increasing the likelihood of successful implementation. The potential of the BECE framework was tested through a pilot workshop focusing on the development of a CE business model through redesign of products and supply chains. Using vacuum cleaners as an illustrative case study, several product design and supply-chain alternatives were identified, including the development of scenarios and action plans for their implementation at the business level. Although the case study focuses on a particular product, the BECE framework is generic and applicable across different products and business sectors. [ABSTRACT FROM AUTHOR]

Energy efficiency of vacuum cleaners has been declining over the past decades while at the same time their number in Europe has been increasing. The European Commission has recently adopted an eco-design regulation to improve the environmental performance of vacuum cleaners. In addition to the existing directive on waste electrical and electronic equipment (WEEE), the regulation could potentially have significant effects on the environmental performance of vacuum cleaners. However, the scale of the effects is currently unknown, beyond scant information on greenhouse gas emissions. Thus, this paper considers for the first time life cycle environmental impacts of vacuum cleaners and the effects of the implementation of these regulations at the European level. The effects of electricity decarbonisation, product lifetime and end-of-life disposal options are also considered. The results suggest that the implementation of the eco-design regulation alone will reduce significantly the impacts from vacuum cleaners (37%–44%) by 2020 compared with current situation. If business as usual continued and the regulation was not implemented, the impacts would be 82%–109% higher by 2020 compared to the impacts with the implementation of the regulation. Improvements associated with the implementation of the WEEE directive will be much smaller (< 1% in 2020). However, if the WEEE directive did not exist, then the impacts would be 2%–21% higher by 2020 relative to the impacts with the implementation of the directive. Further improvements in most impacts (6%–20%) could be achieved by decarbonising the electricity mix. Therefore, energy efficiency measures must be accompanied by appropriate actions to reduce the environmental impacts of electricity generation; otherwise, the benefits of improved energy efficiency could be limited. Moreover, because of expected lower life expectancy of vacuum cleaners and limited availability of some raw materials, the eco-design regulation should be broadened to reduce the impacts from raw materials, production and end-of-life management. [ABSTRACT FROM AUTHOR]

The environmental characterization of the charging infrastructure required to operate electric vehicles (EVs) is usually overlooked in the literature. Only rudimentary life cycle inventories of EV charging facilities are available. This lack of information is especially noticeable in environmental studies of the environmental performance of electric two-wheelers (E2Ws), none of which have included an analysis of charging facilities, even though they constitute the most successful electric-drive market in the world. This article focuses on characterizing the life cycle of the global warming potential (GWP) and primary energy demand (PED) of two conventional charging facility designs that are widely implemented for charging E2Ws in public spaces. The relative environmental relevance of charging facilities per kilowatt-hour (kWh) supplied to E2Ws is determined by considering a range of use scenarios (variability in the service ratio) and the effect of upgrading the electricity mix to include more renewable energy sources. Savings of over 3 metric tons (tonnes) of carbon dioxide equivalent emissions and 56 equivalent gigajoules can be achieved by implementing an optimized charging facility design. The internalization of the relative environmental burden from the charging facility per kWh supplied to E2Ws can increase the GWP of E2Ws' use phase from 1% to 20% and the PED from 1% to 13%. Although the article focuses on one particular case scenario, the research is intended to provide complementary criteria for further research on the life cycle management of electric mobility systems. Thus, a series of factors that can influence the environmental performance of EV charging networks at the macro scale are discussed. [ABSTRACT FROM AUTHOR]

Circular business models, aimed at narrowing, slowing, and closing resource loops, can potentially generate significant economic and social benefits, promote resource security and improve environmental performance. However, within the wind power industry, sustainability research, including life cycle assessments, has been focused mostly on technology innovation at the material (e.g. permanent magnets), components (e.g. blades) or product level (e.g. new assets). Research analysing the implementation of circular business models in the wind industry is scarce. Such information could, however, support more robust decision-making in the development of system-level innovations for the deployment of more resource-efficient and sustainable wind energy infrastructure. Building upon practical methods for the identification, categorisation and characterisation of business models, 14 circular business models with application to the wind industry were comprehensively evaluated through the revision of 125 documents, including 56 journal papers, 46 industrial business cases and 23 wind technology management reports. Each circular business model is examined according to i) business offering and drivers, ii) value creation, delivery and capture mechanisms, iii) sustainability benefits and trade-offs, and iv) industrial challenges and opportunities. Accordingly, comprehensive guidelines to drive political (legislation design and implementation), industrial (technology and business innovation) and academic (further research) actions, are provided. Though the results are focussed on the wind industry, the general findings and recommendations are relevant across the renewable and low-carbon energy sector. • Comprehensive assessment of 125 journal papers, business cases and industrial reports. • Characterisation of 14 CBMs articulated around the life cycle management of wind farms. • Business offering, value creation, delivery and capture mechanisms, and sustainability benefits are evaluated. • Ten intervention areas to overcome CBM implementation challenges are discussed. [ABSTRACT FROM AUTHOR]

The granite production chain is high energy and water intensive with low resource efficiency. This paper focus on characterizing the potential for environmental improvement of the granite production chain by promoting the optimization of sawing technology, the implementation of rainwater harvesting (RWH) and the material recovery of wasted granite (sludge). The environmental performance of multi-blade gangsaw (MBGS) and diamond multi-wire saw (DMWS) technologies is compared by mean of life cycle assessment. Results demonstrate that DMWS technology contribute 30% of water savings, 40% of energy savings and 80% of material savings per square meter of polished granite tiles (60 x 40 x 2 cm) production. These resource savings contribute together to reduce the product's environmental footprint by 35% to 80%. The potential for RWH is analyzed using Plugrisost® simulation software based on system dynamics. RWH depends on the relationship between rainfall, catchment surface and tank size according to the industrial process’s water demand. The results demonstrate major potential to satisfy over 50% of the systemś daily water requirements using rainwater stored in rainwater tanks of varying capacity. RWH is a sustainable strategy for industrial water cycle management. A comprehensive review of literature reveals a range of technically feasible alternatives to promote material recovery of granite sludge. The ceramic industry is one promising industrial endpoint with which to avoid waste landfilling and contribute to mineral, energy and water savings. This by-product synergy could also serve as starting point for springboarding exchanges with other industrial agents, becoming a global extension of resource efficiency. [ABSTRACT FROM AUTHOR]

This paper examines the relevance of incorporating comprehensive life-cycle environmental data into the design and management of pedestrian pavements to minimize the impact on the built environment. The overall primary energy demand and global warming potential of concrete, asphalt and granite sidewalks are assessed. A design with a long functional lifetime reduces its overall primary energy demand and global warming potential due to lower maintenance and repair requirements. However, long-lived construction solutions do not ensure a lower life-cycle primary energy demand and global warming potential than for shorter-lived designs; these values depend on the environmental suitability of the materials chosen for paving. Asphalt sidewalks reduce long-term global warming potential under exposure conditions where the functional lifetime of the pavements is less than 15 years. In places where it is known that a concrete sidewalk can have a life of at least 40 years, a concrete sidewalk is the best for minimizing both long-term primary energy demand and global warming potential. Granite sidewalks are the largest energy consumers and greenhouse gas contributors. [ABSTRACT FROM AUTHOR]

Between 117 and 200 million kettles are used in the European Union (EU) every year. However, the full environmental impacts of kettles remain largely unknown. This paper presents a comprehensive life cycle assessment of conventional plastic and metallic kettles in comparison with eco-kettles. The results show that the use stage contributes 80% to the impacts. For this reason, the eco-kettle has over 30% lower environmental impacts due to a greater water efficiency and related lower energy consumption. These results have been extrapolated to the EU level to consider the implications for proposed eco-design regulations. For these purposes, the effects on the impacts of durability of kettles and improvements in their energy and water efficiency have been assessed as they have been identified as two key parameters in the proposed regulations. The results suggest that increasing the current average durability from 4.4 to seven years would reduce the impacts by less than 5%. Thus, improving durability is not a key issue for improving the environmental performance of kettles and does not justify the need for an eco-design regulation based exclusively on it. However, improvements in water and energy efficiency through eco-design can bring relevant environmental savings. Boiling the exact amount of water needed would reduce the impacts by around a third and using water temperature control by further 2%–5%. The study has also considered the effects of reducing significantly the number of kettles in use after the UK (large user of kettles) leaves the EU and reducing the excess water typically boiled by the consumer. Even under these circumstances, the environmental savings justify the development of a specific EU eco-design regulation for kettles. However, consumer engagement will be key to the implementation and achievement of the expected environmental benefits. [ABSTRACT FROM AUTHOR]

The service sector has the potential to play an instrumental role in the shift towards circular economy due to its strategic position between manufacturers and end-users. However, there is a paucity of supporting methodologies and real-life applications to demonstrate how service-oriented companies can implement circular economy principles in daily business practice. This paper addresses this gap by analysing the potential of service-oriented companies in the information and communication technology (ICT) sector to build and implement circular economy business models. To this end, the Backcasting and Eco-design for the Circular Economy (BECE) framework is applied in an ICT firm. BECE, previously developed and demonstrated for product-oriented applications, has been developed further here for applications in the service sector. By shifting the focus from a product-oriented approach to a user-centred eco-design, the paper shows how ICT firms can identify, evaluate and prioritise sustainable business model innovations for circular economy. The two most promising business model innovations are explored strategically with the aim of designing circular economy models consistent with the company's priorities of customer satisfaction and profitability. The findings suggest that ICT companies may be able to support the deployment of a circular economy in the service-oriented technology sector. Importantly, micro and small organisations can play a fundamental role if provided with macro-level support to overcome company-level barriers. Finally, the BECE framework is shown to be a valuable resource to explore, analyse and guide the implementation of circular economy opportunities in service-oriented organisations. Further research to verify the application of the findings to other service-oriented organisations is recommended. [ABSTRACT FROM AUTHOR]

Circular economy (CE) strategies, aimed at reducing resource consumption and waste generation, can help mitigate the environmental impacts of battery electric vehicles (BEV), thereby providing a more efficient alternative to petrol-fuelled vehicles. Lithium-ion batteries (LIB) are commonly used in BEV because of their higher performance than that of the benchmarks. However, how to analyse the CE innovations through life-cycle assessment (LCA) and how environmental savings relate to different CE strategies remain unclear. Therefore, the purpose of this study was to i) identify and characterise the CE strategies most studied thus far in LCA studies on electric vehicle batteries, ii) evaluate the reasons behind the variability in the environmental impacts and savings between LIB with different chemistries, and iii) provide guidelines for the development of robust LCA studies for LIB by integrating CE management scenarios. The results showed that LCA-supported CE strategies have not been sufficiently explored in the literature, causing variability in methodological choices and research outcomes. While battery recycling was a dominant topic contemplated in 80% of the analysed LCA studies, other CE strategies, such as battery upgrading or remanufacturing, received little attention. The normalised impacts for LIB varied from 4400 kg CO 2 eq. to 55,000 kg CO 2 eq. based on several factors subject to the practitioners' choices, such as the battery chemistry considered, impact assessment method applied, available inventories used, and the CE scenario analysed. LCA methodological guidelines for determining the environmental sustainability of the CE strategies for electric vehicle batteries were provided based on the findings. • Comprehensive review of life cycle assessment and circular economy studies. • Battery longevity is the most important factor for reducing resource consumption. • Repurposing batteries to stationary energy storage leads to notable impact reduction. • Direct cathode recycling is the best end of life process to mitigate carbon emissions. • A holistic analysis of the suitability of circular economy strategies is yet lacking. [ABSTRACT FROM AUTHOR]

The construction of innovative urban agriculture systems in cities has increased due to food and environmental concerns. While the environmental performance of urban agriculture has been extensively studied, research on the life cycle costs of urban agriculture systems is still limited, which constraints sustainability-oriented decision-making processes. This paper analyses the economic viability of tomato production cycle in an innovative building with an integrated urban agriculture system in rooftop by applying the life cycle cost methodology. The data was collected from direct measurements and internal and external sources. To calculate labour costs, a customised data collection sheet was created. The results are presented by life cycle stage, cost category and type of cost (fixed & variable). Results indicate that the main cost drivers for tomato production are labour (24.7%), the rooftop greenhouse structure (15%), external pest control (12.6%), and rainwater consumption (9.5%), accounting altogether for 61.8% of the total costs. Accordingly, cost reduction solutions are evaluated through the development of sensitivity scenarios (rooftop greenhouse structure design, tap water use and rainwater tank size), including the consideration of another relevant aspect, such as the role of the production level output, as it can greatly influence the economic viability and profitability. Finally, the main environmental and social aspects of these urban production systems are also included. [Display omitted] • Life cycle costs are classified by life cycle stage, cost category and fixed (51.4%) and variable (48.6%) costs. • 61.8% of the total cost includes labour (24.7%), greenhouse structure (15%), pest control (12.6%), and rainwater (9.5%). • Strategies to reduce main costs, based on sensitivity analysis, are proposed. • Production output level is also evaluated. [ABSTRACT FROM AUTHOR]

The construction sector represents one of the most significant sources of waste generation in the European Union (EU), with nearly one billion tonnes of construction and demolition waste annually. This sector also contributes a third of the annual EU greenhouse gas (GHG) emissions. Accordingly, construction represents one priority area for intervention within the EU Action Plan for the Circular Economy. Increasing resource efficiency through slowing, closing, and narrowing material and energy loops, is key to mitigating climate change. However, this review paper demonstrates that the analysis of links between circular economy solutions and climate change mitigation has been scarce, despite a recent sharp increase in related literature, with 20 articles (83%) published in 2018–2019. Slowing resource solutions have been the focus of the research and could bring up to 99% savings in GHG emissions per functional unit, where material reuse stands out as the most promising alternative. Closing resource solutions can reduce emissions by 30–50% per functional unit, but results are highly dependent on recycling efficiencies and transportation distances to recovery facilities. Solutions for narrowing resource loops can bring additional GHG savings, but they remain understudied. Despite the promising results for mitigating GHG emissions, this article argues that the circular economy solutions do not always result by default in emission reductions and that a case-by-case quantification is crucial. The implementation of these solutions should be accompanied with further methodological development, such as proper allocation procedures, accurate definition of the system boundaries and integration of forecasts. • First review of circular economy (CE) and climate change in EU construction sector. • Slowing resource solutions have received more attention than narrowing & closing. • Material reuse is the most recommended solution to increase resource efficiency. • Significant carbon reductions can be achieved but a case-by-case analysis is needed. • Sectorial & methodological barriers must be overcome for sustainable CE application. [ABSTRACT FROM AUTHOR]