ALBERT

Description: Sustainable urban resource management depends essentially on a sound understanding of a city's resource flows. One established method for analyzing the urban metabolism (UM) is the Eurostat material flow analysis (MFA). However, for a comprehensive assessment of the UM, this method has its limitations. It does not account for all relevant resource flows, such as locally sourced resources, and it does not differentiate between flows that are associated with the city's resource consumption and resources that only pass through the city. This research sought to gain insights into the UM of Amsterdam by performing an MFA employing the Eurostat method. Modifications to that method were made to enhance its performance for comprehensive UM analyses. A case study of Amsterdam for the year 2012 was conducted and the results of the Eurostat and the modified Eurostat method were compared. The results show that Amsterdam's metabolism is dominated by water flows and by port-related throughput of fossil fuels. The modified Eurostat method provides a deeper understanding of the UM than the urban Eurostat MFA attributed to three major benefits of the proposed modifications. First, the MFA presents a more complete image of the flows in the UM. Second, the modified resource classification presents findings in more detail. Third, explicating throughput flows yields a much-improved insight into the nature of a city's imports, exports, and stock. Overall, these advancements provide a deeper understanding of the UM and make the MFA method more useful for sustainable urban resource management.

Description: Product recovery is a major contributor for implementing sustainable business practices. Within such operations, which are either driven by legislation or economic rationales, practitioners face strategic issues concerning reverse market entry and positioning. Although the complexity of acting on reverse markets is widely acknowledged, a comprehensive framework to facilitate decision making in this area is lacking. In an attempt to fill that gap, we develop a model that supports original equipment manufacturers’ (OEMs’) assessment of the attractiveness of reverse markets. We identify, from a comprehensive literature analysis, in-depth interviews, and engagement with a dozen companies from different countries, factors that influence key characteristics of reverse markets, and consolidate this lengthy list into a comprehensive model intuitively applicable to business practice. The model combines five forces that drive reverse markets: access to recoverable products; threat of independent recovery companies’ (IRCs’) market entry; rivalry for recoverable products; adverse effects on core business; and remarketing opportunities. We propose for each a set of attributes that influences its power and direction. To demonstrate the efficacy of the model, we apply it in two industry settings: recovery of white goods in the United Kingdom and paper recycling in Germany. The present research enables OEMs to understand the structure and forces that drive reverse markets, identify levers to influence those markets, anticipate market developments, and formulate resilient strategies for product recovery.

Description: The concept of industrial symbiosis (IS) was introduced decades ago and its environmental and economic benefits are well established, but the broad acceptance of IS still faces significant barriers. This article provides a new approach to capture synergies within industrial parks by suggesting a new business model. Building on findings from a survey conducted by the authors and on literature, we first identify potential barriers to low-carbon synergistic projects. Economic concerns of technically feasible synergies and financial issues turn out to be the largest barriers, because of long payback periods and fluctuating raw material and by-product market prices. Existing business models do not offer easy ways to overcome or relax these barriers. We therefore introduce the concept of a synergy management services company (SMSCO), a synergy contractor and third-party financing model, to overcome these barriers. This model shifts the financial risk of the synergistic project from collaborating firms to the SMSCO. We posit that this attribute of the SMSCO model makes it attractive for industrial park operators who seek long-term solutions to secure future viability of their park.

Description: In this study, a substance flow analysis (SFA) for copper (Cu) was conducted, in which the inflow, stock, and outflow (in the form of diffuse emissions to soil and water) for Stockholm were estimated for 2013 and compared with a previous study from 1995, hence allowing a discussion on changes over time. A large number of applications containing Cu were analyzed (including power cables, copper alloys, heavy electrical equipment, tap water systems, roofs, cars, various consumer electronics, wood preservatives, and contact cables for the railroad). The results show that the inflow of Cu to Stockholm has increased between 1995 and 2013, both in total and per person, mainly as the result of an increase in heavy electrical equipment, power cables, and cars. The stock remains relatively unchanged, whereas the outflow has increased. For the outflow, the emission increase from brake linings is of greatest quantitative importance, with an estimated 5.8 tonnes annual emission of Cu to the environment of Stockholm in 2013 compared to 3.9 tonnes in 1995. Given that increasing inflows of limited resources drive the global demand, continuous monitoring of flows through society and management of outflow routes are crucial, including improvement of national legislation and regional environmental plans as well as efforts to increase resource-use efficiency and recycling.

Description: Urban metabolism (UM) is a way of characterizing the flows of materials and energy through and within cities. It is based on a comparison of cities to living organisms, which, like cities, require energy and matter flows to function and which generate waste during the mobilization of matter. Over the last 40 years, this approach has been applied in numerous case studies. Because of the data-intensive nature of a UM study, however, this methodology still faces some challenges. One such challenge is that most UM studies only present macroscopic results on either energy, water, or material flows at a particular point in time. This snapshot of a particular flow does not allow the tracing back of the flow's evolution caused by a city's temporal dynamics. To better understand the temporal dynamics of a UM, this article first presents the UM for Brussels Capital Region for 2010, including energy, water, material, and pollution flows. A temporal evaluation of these metabolic flows, as well as some urban characteristics starting from the seminal study of Duvigneaud and Denayer-De Smet in the early 1970s to 2010, is then carried out. This evolution shows that Brussels electricity, natural gas, and water use increased by 160%, 400%, and 15%, respectively, over a period of 40 years, whereas population only increased by 1%. The effect of some urban characteristics on the UM is then briefly explored. Finally, this article succinctly compares the evolution of Brussels’ UM with those of Paris, Vienna, Barcelona, and Hong Kong and concludes by describing further research pathways that enable a better understanding of the complex functioniong of UM over time.

Description: Governments estimate the social and economic impacts of crime, but its environmental impact is largely unacknowledged. Our study addresses this by estimating the carbon footprint of crime in England and Wales and identifies the largest sources of emissions. By applying environmentally extended input-output analysis–derived carbon emission factors to the monetized costs of crime, we estimate that crime committed in 2011 in England and Wales gave rise to over 4 million tonnes of carbon dioxide equivalents. Burglary resulted in the largest proportion of the total footprint (30%), because of the carbon associated with replacing stolen/damaged goods. Emissions arising from criminal justice system services also accounted for a large proportion (21% of all offenses; 49% of police recorded offenses). Focus on these offenses and the carbon efficiency of these services may help reduce the overall emissions that result from crime. However, cutting crime does not automatically result in a net reduction in carbon, given that we need to take account of potential rebound effects. As an example, we consider the impact of reducing domestic burglary by 5%. Calculating this is inherently uncertain given that it depends on assumptions concerning how money would be spent in the absence of crime. We find the most likely rebound effect (our medium estimate) is an increase in emissions of 2%. Despite this uncertainty concerning carbon savings, our study goes some way toward informing policy makers of the scale of the environmental consequences of crime and thus enables it to be taken into account in policy appraisals.

Description: The residential sector constitutes a major energy consumer, particularly on account of its needs for space heating. Offering a high leverage potential, this sector is a suitable starting point for greenhouse gas mitigation policies. By providing predictions of the energy demand of building stocks, bottom-up building energy models represent a first step toward deriving strategies for abatement of detrimental effects related to housing energy use. This article aims at evaluating the performance of a simplified bottom-up housing energy model. A global sensitivity analysis was performed to study the model's structure and the impact of individual model parameters. Moreover, an extensive final energy consumption data set allowed for an in-depth comparison of this model with primary data in the scope of a case study in a Swiss municipality. On an individual building scale, the model fails to accurately simulate the energy demand. Deviations can be attributed to a range of factors, such as variability in occupants’ behavior and problems of representativeness in the underlying statistical database. Nevertheless, such under- or overestimations level off on an aggregated scale. In particular, the model reproduces the overall characteristics of the residential building stock's heating demand well. It is therefore well suited as a building stock model and provides a promising basis for an extended assessment of housing energy demands. In future research work, we will apply this model to a larger region in order to study various types of settlements from a life cycle perspective and to derive targeted measures aimed at reducing environmental impacts.

Description: Potable residential water efficiency and reuse technologies have seen increasing adoption in recent years and have been estimated to demands by up to 50%. In this work, we used an engineering economic model to estimate the technically feasible levelized cost of water provided by seven above-code water efficiency (i.e., beyond that required by building code) and reuse technologies within the Lower Colorado River Authority (LCRA) in central Texas. Unlike other demand-side studies of residential water use, we model uncertainty and variation in technology adoption cost and performance; include reuse technologies; and differentiate between new construction and retrofits. We developed a conservation supply curve to compare the levelized cost of efficiency and reuse technologies with conventional supply-side water management strategies. We estimate that efficiency and reuse in the residential sector can meet 85% of 50-year projected needs (the difference between projected demand and estimated supplies) for the LCRA service area. We also estimate lower levelized costs for immediate retrofits of most technologies, promoting incentives for early technology adoption. However, efficiency and reuse technology performance demonstrates considerable uncertainty and variability. The fraction of demands met by demand-side strategies range from around 60% to 100%. Occupancy drives much of the variability because it significantly affects demand. These results promote designing incentives for adoption of water efficiency and reuse technologies based upon use. We find that water-efficient showerheads and bathroom faucet aerators perform well over a variety of assumptions, indicating that these technologies should be a priority for municipalities seeking water demand reductions.

Description: The importance of increase in the scarcity of resources can be assessed using different approaches. Here, we propose a method that is based on the amount of extra ore mined to assess the importance of the extraction of resources. The surplus ore potential (SOP) indicator quantifies the extra amount of ore mined per additional unit of resource extracted by applying log-logistic cumulative grade-tonnage relationships and reserve estimates. We derived SOPs for 18 resources (17 metals including uranium and phosphorus) with 5 orders of magnitude difference (between 4.1 × 10 −1 kilograms [kg] of extra ore per kg of manganese extracted and 5.5 × 10 4 kg of extra ore per kg of gold extracted). The sensitivity of the SOP values to the choice of reserve estimates (reserves vs. ultimate recoverable resource) are within a factor of 3 of each other. Combining the SOP values with the 2012 global extraction rates of these 18 resources resulted in a 236 to 372 kg ore /capita surplus ore extracted. Iron, phosphorus, copper, gold, and aluminium were the largest contributors. The large variation in SOP values we observed between resources emphasizes the potential relevance of including resource-specific SOP values to assess the contribution to resource scarcity by specific products and technologies.

Description: The carbon footprint (CF) of biofuels and biomaterials is a barrier to their acceptance, yet the greenhouse gas emissions associated with disposing of biomaterials are frequently omitted from analyses. This article investigates whether harmonization is appropriate for calculating the importance of biomaterials’ disposal. This research shows that disposal stages could double a biomaterial's CF, or reduce it to the point that it could claim to be zero carbon. Incineration with combined heat and power coupled with on-site energy production in the biorefinery are identified as prerequisites to being zero carbon. The article assesses the current UK waste infrastructure's ability to support a low-carbon bio-based future economy, and finds that presently it only achieves marginal net reductions when compared to landfill and so cannot be said to support low-carbon biomaterials, though the article challenges the polluter pays principle where low-carbon disposal infrastructure are not available. Reuse and recycling are shown to have the potential to offset all the emissions caused by landfill of biomaterials. However, the savings are not so great as to offset the biomaterial's upstream emissions. The study explores the ability to overcome the barriers to incorporating disposal into life cycle assessment while identifying limitations of using harmonization as an assessment method. Specifically, data availability and industry consensus are flagged as major barriers. The study also uses sensitivity analysis to investigate the influence of methodological choices, such as allowing additional reuse and recycling stages, classifying biomaterials into different types, and choosing between opposing allocation methods.

Description: Urban metabolism accounts of total annual energy, water, and other resource flows are increasingly available for a variety of world cities. For local decision makers, however, it may be important to understand the variations of resource consumption within the city. Given the difficulty of gathering suburban resource consumption data for many cities, this article investigates the potential of statistical downscaling methods to estimate local resource consumption using socioeconomic or other data sources. We evaluate six classes of downscaling methods: ratio-based normalization; linear regression (both internally and externally calibrated); linear regression with spatial autocorrelation; multilevel linear regression; and a basic Bayesian analysis. The methods were applied to domestic energy consumption in London, UK, and our results show that it is possible to downscale aggregate resource consumption to smaller geographies with an average absolute prediction error of around 20%; however, performance varies widely by method, geography size, and fuel type. We also show how mapping these results can quickly identify districts with noteworthy resource consumption profiles. Further work should explore the design of local data collection strategies to enhance these methods and apply the techniques to other urban resources such as water or waste.

Description: One goal of the local-to-global research program is to explore ways to reduce, if not reverse, threats to sustainability through analysis using mathematical models applied to shared databases. This article describes a global case-study framework for reconciling top-down with bottom-up approaches so they are mutually reinforcing for identifying and evaluating the effectiveness of different scenarios describing potential future actions. A strategic selection of cases makes it possible to distinguish and represent concrete characteristics of both common and atypical situations, whereas a global model is needed to provide an integrating conceptual framework based on a theory of consumption, production, and international exchanges that captures interdependencies among activities across regions. I discuss how the results of global analyses can be useful for framing case-study questions and selecting cases, whereas the cases, in turn, identify concerns of specific stakeholders and provide detailed information, including technical data, to supplement economic databases with their accounting origins. I describe ways to enhance collaborations between top-down and bottom-up researchers, using global, multiregional input-output databases to play a mediating role, while avoiding rigidities of premature closure and incorporating diverse perspectives. Responding to the high-priority global challenge of vastly expanding effective sanitation services in developing countries is used to illustrate these ideas.

Description: Inequality has recently become a major concern in economics. Leaving aside its social and economic effects is also possible to trace its environmental consequences, which this article attempts to assess. The indicator to be measured is the household's carbon footprint (CF) for different social groups. The deep economic crisis in the Spanish economy between 2008 and 2013 has increased consumption inequality and doubled the number of households below the poverty line. When focusing on domestic consumption, we found that the shopping basket of all income groups has very similar emissions intensities; therefore, the differences among the household CFs depend mainly on the scale effect (i.e., the size of consumption). However, when international trade is also considered, we found that the emission intensity of imports is bigger than the intensity of all the respective domestic goods. Therefore, the share of imported goods and services by social class will be an important determinant of the respective total CF. Before the crisis, households with higher incomes imported 30% of their total consumption items whereas households with lower income imported only 20% of their consumption. During the crisis, the imports of medium-high-income households fell to 20%, whereas low- and middle-income families maintained the same import share, which contributed to the reduction of the total household CF.

Description: Although evidence indicates the significant incidence of child labor in India, the role it plays in the economy is still considerably unknown. This study used disaggregated labor data and evaluated local and global supply chains to develop the first comprehensive and systematic assessment of Indian child labor involved in the production of commodities consumed worldwide, considering trade between more than 15,000 industrial sectors across 189 countries. Five questions were addressed: Which children are in child labor?; What is being produced with that labor?; Who are the final consumers?; What amount of financial resources would be needed to support these children?; and What would be the increase in labor production costs if adults were to replace children? It was found that of 9,687,688 children in child labor during July 2011 to June 2012, 95% of cases were linked to the production of just 35 commodities. Whereas most of these commodities were locally consumed, as many as 980,084 children (around 10%) worked for exports, more than what is typically assumed. Exports mainly consisted of agricultural and food products, clothing, minerals, and construction materials and were predominantly destined to 26 countries, the United States ranking first. Nonetheless, this study supports the notion that the simple removal of foreign demand will not solve the problem; it is poverty that needs to be addressed. Supporting children with allowances equal to their earnings would require 935 billion Indian Rupees, within a 13-year period. If adult workers were to replace children, total production costs may increase only by around 1%.

Description: In view of urbanization trends coupled with climate-change challenges, it is increasingly important to establish less-harmful means of urban living. To date, urban metabolism (UM) studies have quantified the aggregate material and energy flows into and out of cities and, further, have identified how consumer activity causes these flows. However, little attention has been paid to the networks of conversion processes that link consumer end-use demands to aggregate metabolic flows. Here, we conduct a systematic literature search to assemble a database of 202 urban energy, water, and waste management processes. We show how the database can help planners and policy makers choose the preferred process to meet a specific resource management need; identify synergies between energy, water, and waste management processes; and compute optimal networks of processes to meet an area's consumer demand at minimum environmental cost. We make our database publicly available under an open-source license and discuss the possibilities for how it might be used alongside other industrial ecology data sets to enhance research opportunities. This will encourage more holistic UM analyses, which appreciate how both consumer activity and the engineered urban system work together to influence aggregate metabolic flows and thus support efforts to make cities more sustainable.

Description: France is the second largest exporter of cereals in the world. Although the cereal supply chain is an asset to the country's economy and employment, it is at the same time responsible for a number of pressures on the local and global environment including greenhouse gases (GHG) emissions and stresses on water quality and quantity. This article aims at evaluating this situation from an environmental point of view by linking production occurring in French regions with consumption occurring in France and abroad. Based on previous work on material flow analysis, we use an absorbing Markov chain model to study the fate of French cereals and link worldwide consumption to environmental pressures along the supply chain, that is, induced by production, transformation, or transport. The model is based on physical supply and use tables and distinguishes between 21 industries, 22 products, 38 regions of various spatial resolution (22 French regions, ten countries, six continents), and four modes of transport. Energy use, GHG emissions, land use, use of pesticides, and blue water footprint are studied. Illustrative examples are given in order to demonstrate the versatility of the results produced, for instance: Where and in what form does local production end up? How do regions compare relative to their production and consumption footprints? These results are designed to be a first step toward scenario analysis for decision-aiding that would also include socio-economic indicators. Examples of such scenarios are discussed in the conclusion.

Description: Urban areas (especially cities) are challenged in meeting their direct water needs from local sources. They also exert strain on global water resources through their indirect (virtual) water use. Agencies concerned with urban water management have visions and goals for managing direct water use, but indirect use is only inferred in more global visions for sustainable consumption. There is limited quantification of “urban water performance” at the macro urban scale (whole of city) to monitor progress toward these goals. It is constrained by a lack of clarity about the evaluation approaches that best serve them. We ask, How can the evaluation approaches described in literature advance urban water management goals? We reviewed the utility of eight evaluation approaches, including urban water system modeling, urban metabolism (territorial and mass balance), consumption (life cycle assessment, water footprinting, and input-output analysis), and complex systems (ecological network analysis and systems dynamics) approaches. We found that urban metabolism based on water mass balance is a core method for generating information to inform current goals for direct urban water use, with potential for being “coupled” with the other approaches. Consumption approaches inform the management of indirect water use. We describe this in a framework for urban water evaluation to give greater clarity to this field and flag the further research that would be needed to progress this. It includes the recommendation to differentiate the evaluation of direct and indirect urban water, but to also interpret them together.

Description: Recycling of neodymium and dysprosium is of great interest because of the rapid growth in their demand and limited supply of new resources. To promote recovery from end-of-life (EoL) products, it is desirable to quantify the recycling potentials of neodymium and dysprosium by their end use. This study characterized the substance flows of neodymium and dysprosium associated with neodymium magnets in Japan by conducting a dynamic substance flow analysis. A bottom-up approach was employed in the analysis to estimate annual consumption by end use. Factors used in the analysis were the amounts of rare earth contents, weight of a magnet used for each product, adoption ratios of neodymium magnet usage in each product, and lifetime of products. It was found that the amount of neodymium entering use was approximately half of the domestic consumption; the balance existing in final products that were exported from Japan. The economic feasibility of recycling neodymium magnets was evaluated for their largest two end uses: driving motors in hybrid electric vehicles (HEVs) and compressors in air conditioners. It was found that recycling the neodymium magnets used in the driving motors has the potential for economic feasibility in Japan. The result showed that lower transportation costs for recovered magnets can make the recycling economically feasible regardless of the content rate and the price of metals. The future increase of EoL HEVs contributes to the feasibility of recycling with a profit in the upcoming years. Strategies for more profitable recycling are concentrating scrap motors or magnets among recycling factories or selecting specific factories that deal with EoL HEVs.

Description: Urban mining offers an efficient supply of resources because of rich mines and low environmental impacts. Location selection and optimization for urban mining facilities is more complicated than for natural mines, given that it may vary according to the urban population, consumption habits, and economic development. China initiated the National Urban Mining Pilot Bases program in 2010 that targeted 50 national urban mining pilot bases, but unfortunately neglected the location planning issue. Twenty-eight bases have already been selected, which are concentrated in the central and eastern areas of China. This article combines the use of analytic hierarchy process, maximal covering location model, and geographical information systems (GIS) software to optimize locations for China's urban mining pilot bases. Primary findings show that, theoretically, 40 urban mining pilot bases can sufficiently provide maximum gross domestic product (GDP) and population coverage service for China. Taking the current 28 bases as a precondition and 50 bases as the remaining policy target, our second optimization results in a list of 22 cities for the location selection of future urban mining pilot bases. In total, the optimized 22 cities, together with the selected 28 bases, can provide a maximum 97.5% of GDP and 95.1% of population coverage in China. This study illustrates the optimization process for urban mining recycling facilities in general and provides policy advice for China in a specific case.

Description: Industrial symbiosis (IS), one of the founding notions within the field of industrial ecology, has diffused throughout significant parts of the world as a practice that can reduce the ecological impact of the industrial processes of groups of firms. In this article, we propose a fresh look at this research topic, building on the considerable advances that have been made in the last 15 years in understanding how IS comes about. We propose a conceptual and theoretical framework for taking on the challenge of comparative analysis at a global level. This requires developing an approach to address a solution to the problem of equivalence: the difficulty of comparing instances of IS across different institutional contexts. The proposed framework emphasizes IS as a process and attempts to address the obstacles to comparative study by (1) identifying terminology to examine IS variants, (2) providing a typology of IS dynamics, and (3) formulating key research questions to illuminate a way forward. In developing our argument, we build on the collective experiences of collaborative research efforts in North America, Europe, and Asia as evidenced in recent overviews of the literature.

Description: An integrated life cycle assessment and life cycle cost (LCC) model was developed to compare the life cycle performance of plug-in charging versus wireless charging for an electric bus system. The model was based on a bus system simulation using existing transit bus routes in the Ann Arbor–Ypsilanti metro area in Michigan. The objective is to evaluate the LCCs for an all-electric bus system utilizing either plug-in or wireless charging and also compare these costs to both conventional pure diesel and hybrid bus systems. Despite a higher initial infrastructure investment for off-board wireless chargers deployed across the service region, the wireless charging bus system has the lowest LCC of US$0.99 per bus-kilometer among the four systems and has the potential to reduce use-phase carbon emissions attributable to the lightweighting benefits of on-board battery downsizing compared to plug-in charging. Further uncertainty analysis and sensitivity analysis indicate that the unit price of battery pack and day or night electricity price are key parameters in differentiating the LCCs between plug-in and wireless charging. Additionally, scenario analyses on battery recycling, carbon emission pricing, and discount rates were conducted to further analyze and compare their respective life cycle performance.

Description: In the study of sustainable building materials, the comparison of the life cycle environmental performance of steel and reinforced concrete has been a popular and important topic. Based in Singapore, this is one of the first studies in the literature that applies both attributional and consequential life cycle approaches to compare the global warming potential and embodied energies of these two materials, which are widely used for the structural parts of buildings. It was found that 1 kilogram (kg) of steel can be replaced by 1 or 4.25 kg of reinforced concrete. Two consequential scenarios for each of three combinations of primary and secondary steel were assessed. It was found that reinforced concrete produces less carbon dioxide emissions and incurs less embodied energy in most of these cases, but when different sustainable primary steel-making technologies were incorporated, these results may be reversed. We applied consequential life cycle assessment and scenario analysis to describe how changes in the demand for structural steel and reinforced concrete in Singapore's building industry give rise to different environmental impacts. Specifically, the consequential life cycle approach revealed that, over the short term, the impact of substituting steel with reinforced concrete depends on the difference in impacts resulting from the transportation of these two materials within Singapore. Based on these lessons, integrated technology policies to improve the overall sustainability of using steel for construction were proposed.

Description: China produces and consumes a large amount of batteries annually, which leads to many waste batteries needing to be recycled. The collection and recycling system of primary, alkaline secondary, and lithium-ion secondary batteries in China is particularly poor, and waste battery recycling enterprises generally sustain economic losses if they solely use waste batteries as raw materials. Increasing the profits of waste battery recycling systems is a key problem that needs to be considered. This article quantitatively analyzes waste battery generation in China by using annual sales data and probable lifetime distribution of various batteries. The results show that the rapid growth of battery usage has led to an increased generation of waste batteries and the percentage of different types of waste batteries is changing over time. In 2013, the total quantity of all waste batteries in the medium lifetime scenario reached 570 kilotons, of which primary, alkaline secondary, and lithium-ion secondary waste batteries accounted for approximately 36%, 28%, and 35%, respectively. Based on a real-world case study of a typical domestic waste battery recycling enterprise in China, material flow analysis and cost-benefit analysis were conducted to study the development of the recycling process of comingled waste batteries. Through scenario analysis, we conclude that increasing the use of waste batteries as raw materials and the recycling of other materials that are less valuable reduces the profits of the waste battery recycling enterprise. Higher profits can be achieved by adding the production of high value-added downstream products and government support. At the same time, the essential role of the government in developing a waste battery recycling system was identified. Finally, relevant suggestions are made for improvements in both the government and enterprise sectors.

Description: According to previous studies, the life cycle energy intensity of an offshore wind farm (OWF) varies between 0.03 and 0.13 megawatt-hours (MWh) of primary energy for each MWh of electricity generated. The variation in these life cycle energy intensity studies, after normalizing for capacity factor and life span, is significantly affected by OWF location because of geographical properties, namely, wind speed and water depth. To improve OWF siting, this study investigates how an OWF's distance from shore and geographical location impacts its environmental benefit. A process-based life cycle assessment is conducted to compare 20 OWF siting scenarios in Michigan's Great Lakes for their cumulative fossil energy demand, global warming potential, and acidification potential. Each scenario (four lake locations at five offshore distances) has unique foundation, transmission, installation, and operational requirements based on site characteristics. The results demonstrate that the cumulative environmental burden from an OWF is most significantly affected by (1) water depth, (2) distance from shore, and (3) distance to power grid, in descending order of importance, if all other site-relevant variables are held constant. The results also show that when OWFs are sited further offshore, the benefit of increased wind energy generation does not necessarily outweigh the increase in negative environmental impacts. This suggests that siting OWF nearer to shore may result in a better life cycle environmental performance. Finally, we demonstrate how much an OWF's environmental burdens can be reduced if the OWF system is either recycled, transported a shorter distance, or manufactured in a region with a high degree of renewable energy on the grid.

Description: The building stock is not only a huge consumer of resources (for its construction and operation), but also represents a significant source for the future supply of metallic and mineral resources. This article describes how material stocks in buildings and their spatial distribution can be analyzed on a city level. In particular, the building structure (buildings differentiated by construction period and utilization) of Vienna is analyzed by joining available geographical information systems (GIS) data from various municipal authorities. Specific material intensities for different building categories (differentiated by construction period and utilization) are generated based on multiple data sources on the material composition of different building types and combined with the data on the building structure. Utilizing these methods, the overall material stock in buildings in Vienna was calculated to be380 million metric tonnes (t), which equals 210 t per capita (t/cap). The bulk of the material (〉96%) is mineral, whereas organic materials (wood, plastics, bitumen, and so on) and metals (iron/steel, lead, copper, aluminum, and so on) constitute a very small share, of which wood (4.1 t/cap) and steel (3.2 t/cap) are the major contributors. Besides the overall material stock, the spatial distribution of materials within the municipal area can be assessed. This research forms the basis for a resource cadaster, which provides information about gross volume, construction period, utilization, and material composition for each building in Vienna.

Description: At the local scale, interconnected production, consumption, waste management, and other man-made technological components interact with local ecosystem components to form a local production system. The purpose of this work is to develop a framework for the conceptual characterization and mathematical modeling of a local production system to support the assessment of process and component options that potentially create symbiosis between industry and ecosystem. This framework has been applied to a case study to assess options for the establishment of a local energy production system that involves a heathland ecosystem, bioenergy production, and wastewater treatment. We found that the framework is useful to analyze the two-way interactions between these components in order to obtain insight into the behavior and performance of the bioenergy production system. In particular, the framework enables exploring the levels of the ecosystem states that allow continuous provisioning of resources in order to establish a sustainable techno-ecological system.

Description: This study extends existing life cycle assessment (LCA) literature by assessing seven environmental burdens and an overall monetized environmental score for eight recycle, bury, or burn options to manage clean wood wastes generated at construction and demolition activity sites. The study assesses direct environmental impacts along with substitution effects from displacing fossil fuels and managed forest wood sourcing activities. Follow-on effects on forest carbon stocks, land use, and fuel markets are not assessed. Sensitivity analysis addresses landfill carbon storage and biodegradation rates, atmospheric emissions controls, displaced fuel types, and two alternative carbon accounting methods commonly used for waste management LCAs. Base-case carbon accounting considers emissions and uptakes of all biogenic and fossil carbon compounds, including biogenic carbon dioxide. Base-case results show that recycling options (recycling into reconstituted wood products or into wood pulp for papermaking) rank better than all burning or burying options for overall monetized score as well as for climate impacts, except that wood substitution for coal in industrial boilers is slightly better than recycling for the climate. Wood substitution for natural gas boiler fuel has the highest environmental impacts. Sensitivity analysis shows the overall monetized score rankings for recycling options to be robust except for the carbon accounting method, for which all options are highly sensitive. Under one of the alternative methods, wood substitution for coal boiler fuel and landfill options with high methane capture efficiency are the best for the overall score; recycling options are next to the worst. Under the other accounting alternative, wood substitution for coal and waste-to-energy are the best, followed by recycling options.

Description: Environmentally extended input-output (EEIO) databases are increasingly used to examine environmental footprints of economic activities. Studies focusing on China have independently, repeatedly developed EEIO databases for China. These databases are usually not publicly available, leading to repeated efforts, inconsistent with one another using different approaches, of limited environmental accounts, and lacking transparency, preventing continuous updating. We developed a transparent, comprehensive, and consistent Chinese EEIO database covering a wide period of time (currently 1992, 1997, 2002, and 2007 for which benchmark input-output tables [IOTs] are available), sector classifications (original sector classifications in benchmark IOTs, a 45-sector classification commonly used in China's environmental and energy statistics, and a 91-sector classification with maximized sector resolution ensuring temporal consistence), and environmental satellite accounts for 256 types of resources and 30 types of pollutants in this study. Moreover, the environmental satellite accounts cover households in addition to sectors, allowing developing closed models. We make this database publicly available with open access for broader dissemination ( www.ceeio.com ). We demonstrate the database by evaluating environmental pressures of Chinese products in 2007. Comparisons of our database with previous studies validate its rationality and reliability.

Description: Despite accounting for almost 50% of global material use, nonmetallic minerals—mostly used for construction of buildings and infrastructure—are the material flow analysis (MFA) category with the highest uncertainty. The main reason for this is incomplete reporting in official national statistics because of ease of availability and the low per-unit cost of these materials. However, the environmental burden associated with nonmetallic minerals, which include energy use for extraction and transport, land-use change, and disposal of large amounts of construction demolition waste, call for a thorough understanding of the magnitude of nonmetallic mineral flows. Previous estimates for nonmetallic minerals have used simplistic assumptions. This study aims to increase the precision of nonmetallic mineral accounts at national and global level using consumption of bitumen, bricks, cement, and railways in combination with technical coefficients from the engineering literature to infer the actual yearly consumption of nonmetallic minerals. We estimate the extraction of nonmetallic minerals and provide uncertainty estimates for the new accounts as well as information about consumption by different sectors. Analyzing the evolution of consumption for seven world regions, we find that, in North America and Europe, the consumption of nonmetallic minerals over the past 40 years has followed the growth patterns of population, whereas for all other regions consumption has been closely related to gross domestic product (GDP). A more accurate account of global and country-by-country extraction of nonmetallic minerals may provide insights into supply shortages and inform waste management strategies for construction and demolition waste.

Description: As a leading university in engineering education in China, Tsinghua University implemented industrial ecology (IE) education in the 1990s. This article describes the evolution of IE education at Tsinghua. Tsinghua mainstreams IE education into green education and engineering education not only by establishing independent courses of IE for both undergraduate and graduate students, but also by incorporating IE principles and knowledge modules into an increasing number of courses. During 2002–2015, a total of 1,023 undergraduates from 33 schools and departments participated in an IE course. To cope with the diversity of participants, four knowledge modules were customized for an undergraduate course: concepts and history; methods and tools; topics and applications; and policy and perspectives. Meanwhile, an interdisciplinary teaching method was adopted by inviting experts from diverse disciplines and organizing group discussions. Though the course has received strong positive feedback, four challenges still remain in IE education: defining the knowledge boundary, presenting an integrated view, utilizing an interdisciplinary methodology, and cultivating a class culture.

Description: The development of renewable and sustainable energy is advanced by public financial support. This is particularly so in the German Energiewende , which seeks to replace nuclear and fossil electricity generation with wind, sun, and biomass. We study the impact of the (changes in the) feed-in tariff (FIT) policy on the investment in wind electricity generation capacity in Germany in the period 2000–2014. We estimate a generic investment model that includes this support mechanism, the cost of capital, investment risks such as wind and price volatility, and manufacturing costs. We discuss specific features for different types of wind energy investors, such as the incumbents, small private investors, diversified companies, and independent power producers. We find that a change in the FIT has a negative impact on investment capacity regarding the generation of wind energy: A one monetary unit increase in the variation of the tariff is to be associated with a decrease by 0.17 megawatts of wind capacity installed. We argue that it is policy uncertainty that makes investors shy away from making real investments. We also argue that the drivers for wind energy investment can differ along different types of firms. For the traditional power producers, especially electricity price volatility, construction costs, and carbon prices seem to matter. But for the other investor types, the FIT is crucial indeed.

Description: Urban energy metabolism includes processes for exploiting, transforming, and consuming energy, as well as processes for recycling by-products and wastes. Embodied energy is the energy consumed during all of these activities, both directly and indirectly. Multiregional input-output (MRIO) analysis can calculate the energy consumption embodied in flows among sectors for multiple cities or regions. Our goal was to address a problem apparent in previous research, which was insufficient attention to indirect energy flows. We combined MRIO analysis with ecological network analysis to calculate the embodied energy consumption and the energy-related carbon footprints of five sectors in three regions that comprise the Jing-Jin-Ji agglomeration, using data from 2002 and 2007. Our analysis traced metabolic processes of sectors from the perspective of final consumption. Based on the embodied energy analysis, we quantified the indirect energy consumption implied in exchanges of sectors and its distribution and identified the relationships formed through the indirect consumption to analyze the roles of providers and receivers in the system. Results showed that the embodied energy consumption for the Jing-Jin-Ji region increased from 2002 to 2007 as a result of increased energy consumption in Tianjin and Hebei. Overall, consumption of Beijing decreased likely attributable to the fact that government policies relocated industries during this time in anticipation of the Olympic Games. The relationships among sectors changed: Beijing changed from a net exporter to an importer, whereas Hebei changed from a net importer of energy from Beijing to an exporter to Beijing, and Tianjin served as an importer in both years.

Description: Regional economic development in China has resulted in an unbalanced distribution of resources and frequent exchanges of resources and products among regions. Therefore, it is necessary to understand these regional differences to support national planning to improve sustainability. In this research, we used energy data and a multiregional input-output table for China in 2002 to analyze the domestic trade among the 30 provinces and seven regions of China. We also quantified the embodied energy flows and their patterns by means of ecological network analysis and looked at different types of relationships between the regions, such as mutualistic or competing relationships. The results show that the flows connected with the Northern and Eastern regions ranked first, and those connected with the Southwestern and Northwestern regions were the smallest. Based on the flows among provinces and regions, we determined the relationships among them. Results show that more than 95% of the total relationships among the regions were exploitation, with only one competition relationship. The Eastern region received the largest input and the highest benefits from their energy exchanges with other regions. Our study of the regional flows and relationships among the regions and provinces provides useful information on the flows and consumption of embodied energy in China, thereby providing insights into the sustainability of these flows and how to promote sustainable development through regional cooperation.

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Description: Urban mining is seen as a key strategy for the recovery of secondary raw materials from the built environment. Although large material stocks have been reported in infrastructure networks, their actual recoverability over time has received little attention so far. This article presents a case study on the prospection and exploration of the anthropogenic resources deposited in Vienna's subway network. After quantifying the built-in materials in the network, a resource classification was performed, distinguishing between (1) materials that have to be replaced and are thus potentially extractable as secondary raw materials after a considerable time span (〈100 years) and (2) materials remaining in the subway and thus are not extractable. Results given in tonnes (t) show that the subway network consists mainly of concrete (12,000,000 t), iron & steel (600,000 t), gravel (300,000 t), bricks (250,000 t), copper (10,000 t), and aluminum (6,000 t). A first evaluation demonstrated that 3% of the built-in materials (mainly copper, aluminum, and gravel) have to be renewed after a considerable time span (〈100 years) and, consequently, can be seen as potentially extractable resources. Ninety-seven percent of the built-in materials were classified as not extractable (mainly concrete, iron & steel, and bricks), because they were found in permanent structures and lines that have been declared as cultural heritage monuments. For the materials that were found to be potentially extractable as secondary raw materials, a further investigation that particularly considers their end of life in practice and the existence of a hibernating stock is required.

Description: This article examines the concept of eco-efficiency at a regional level as an approach to promote the sustainable transformation of regions, using the regions of Poland as an example. The data envelopment analysis (DEA) method—the input-oriented Charnes, Cooper, and Rhodes (CCR) model—was chosen as the eco-efficiency analysis tool because of its high capability to measure the regional eco-efficiency. The research process was divided into two stages. First, the chosen instruments of mathematical statistics (e.g., Hellwig's method and coefficient of determination) were applied to ensure an appropriate combination of environmental and economic indicators of the eco-efficiency equation. Next, the CCR model was used to calculate the eco-efficiency scores. The results of the study have revealed that the regions of Lubuskie, Mazowieckie, Śląskie, Warmińsko-Maurskie, and Wielkopolskie are relatively eco-efficient, whereas the remaining regions use too many environmental resources in relation to the produced value of goods and services. Six of the eleven eco-inefficient regions in Poland have increasing returns to scale, that is, the usage of natural resources connected with the negative impact upon the environment rises slower than the values of goods and services. Notwithstanding, it is beneficiary from the perspective of sustainability. The obtained research results are a valuable source of management information for the creation of regional environmental protection strategies and a basis for searching for the causes of eco-inefficiency.

Description: Additive manufacturing (AM) technology is capable of building up component geometry in a layer-by-layer process, entirely without tools, molds, or dies. One advantage of the approach is that it is capable of efficiently creating complex product geometry. Using experimental data collected during the manufacture of a titanium test part on a variant of AM technology, electron beam melting (EBM), this research studies the effect of a variation in product shape complexity on process energy consumption. This is done by applying a computationally quantifiable convexity-based characteristic associated with shape complexity to the test part and correlating this quantity with per-layer process energy consumption on the EBM system. Only a weak correlation is found between the complexity metric and energy consumption (ρ = .35), suggesting that process energy consumption is indeed not driven by shape complexity. This result is discussed in the context of the energy consumption of computer-controlled machining technology, which forms an important substitute to EBM. This article further discusses the impact of available additional shape complexity at the manufacturing process level on the incentives toward minimization of energy inputs, additional benefits arising later within the product's life cycle, and its implications for value creation possibilities.

Description: This study used two recently developed environmentally extended global multiregional input-output models (EE GMRIOs)—WIOD and EXIOBASE—to assess the global operational footprint of higher education for five impact categories: energy, water, material, and land use, and carbon dioxide (CO 2 ) emissions. The results of our analysis showed that, in 2009, the global environmental impacts attributable to education as a fraction of total global environmental impacts were not more than 2.5% of energy use and CO 2 emissions, and not more than 1.5% of material, water, and land use—the vast majority of impacts generated upstream. These fractions have increased moderately since 1995, potentially driven by increased tertiary enrollment as a fraction of overall enrollment. Analysis of data from the year 2000 showed that, at most, an additional 0.15% for each impact category was attributable to research and development specifically. Inter-regional and sectoral dynamics were also explored. Europe and the Organization for Economic and Cooperative Development (OECD) had lower total impacts than the rest of world, but their intensities per student were greater. Europe and the OECD also disproportionately shift their impacts to the rest of world. Purchases from energy and utility sectors contribute most to education-driven energy usage and CO 2 emissions, whereas purchases from food, hospitality, and agriculture sectors contribute most to water and land usage. Materials usage is driven more evenly by all sectors. The study concludes that higher education should place emphasis on addressing upstream impacts and recognize the importance of its role in global sustainability beyond its operational footprint.

Description: Industrial symbiosis (IS) is the process by which by-products are revalorized and exchanged among distinct business entities. The literature suggests that IS can bring financial, social, and environmental benefits to firms and society. Analytical tools have been developed for uncovering IS arrangements and guidelines suggested for designing IS arrangements where they do not yet exist. Despite these suggested benefits and in spite of these tools, few planned IS arrangements have successfully materialized, with notable exceptions in East Asia. Understanding why IS networks emerge and expand or falter requires both macro- and micro-level analysis. Some explanatory factors have been extensively covered in the IS literature, such as the important role of coordinating organizations. But the analysis of enterprise-level actions and strategies as well as the conditions in the external environment that act on the enterprises and the network are not as well examined. The article outlines an analytical framework that draws upon insights from research on cleaner production, corporate social responsibility, diffusion of innovation, and the role of the state in development. The framework is consistent with the view that the evolution of IS networks is characterized by “equifinality.” Different networks may achieve IS as a result of quite different combinations of factors. No general theory of IS success or decline is offered because no such theory can be expected. IS emergence, development, and disruption is approached as a problem of sociohistorical analysis. For such phenomena, analytical frameworks provide a common explanatory starting point, but no predictive power.

Description: The validity of material flow analyses (MFAs) depends on the available information base, that is, the quality and quantity of available data. MFA data are cross-disciplinary, can have varying formats and qualities, and originate from heterogeneous sources, such as official statistics, scientific models, or expert estimations. Statistical methods for data evaluation are most often inadequate, because MFA data are typically isolated values rather than extensive data sets. In consideration of the properties of MFA data, a data characterization framework for MFA is presented. It consists of an MFA data terminology, a data characterization matrix, and a procedure for database analysis. The framework facilitates systematic data characterization by cell-level tagging of data with data attributes. Data attributes represent data characteristics and metainformation regarding statistical properties, meaning, origination, and application of the data. The data characterization framework is illustrated in a case study of a national phosphorus budget. This work furthers understanding of the information basis of material flow systems, promotes the transparent documentation and precise communication of MFA input data, and can be the foundation for better data interpretation and comprehensive data quality evaluation.

Description: Life cycle greenhouse gas (LC-GHG) emissions from electricity generated by a specific resource, such as gas and oil, are commonly reported on a country-by-country basis. Estimation of variability in LC-GHG emissions of individual power plants can, however, be particularly useful to evaluate or identify appropriate environmental policy measures. Here, we developed a regression model to predict LC-GHG emissions per kilowatt-hour (kWh) of electricity produced by individual gas- and oil-fired power plants across the world. The regression model uses power plant characteristics as predictors, including capacity, age, fuel type (fuel oil or natural gas), and technology type (single or combined cycle) of the plant. The predictive power of the model was relatively high (R 2 = 81% for predictions). Fuel and technology type were identified as the most important predictors. Estimated emission factors ranged from 0.45 to 1.16 kilograms carbon dioxide equivalents per kilowatt-hour (kg CO 2 -eq/kWh) and were clearly different between natural gas combined cycle (0.45 to 0.57 kg CO 2 -eq/kWh), natural gas single cycle (0.66 to 0.85 kg CO 2 -eq/kWh), oil combined cycle power plants (0.63 to 0.79 kg CO 2 -eq/kWh), and oil single cycle (0.94 to 1.16 kg CO 2 -eq/kWh). Our results thus indicate that emission data averaged by fuel and technology type can be profitably used to estimate the emissions of individual plants.

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Description: The portfolio of impacts that are quantified in life cycle assessment (LCA) has grown to include rather different stressors than those that were the focus of early LCAs. Some of the newest life cycle impact assessment (LCIA) models are still in an early phase of development and have not yet been included in any LCA study. This is the case for sound emissions and noise impacts, which have been only recently modeled. Sound emissions are matter-less, time dependent, and bound to the physical properties of waves. The way sound emissions and the relative noise impacts are modeled in LCA can show how new or existing matter-less impacts can be addressed. In this study, we analyze, through the example of sound emissions, the specific features of a matter-less impact that does not stem from the use of a kilogram of matter, nor is related to the emission of a kilogram of matter. We take as a case study the production of energy by means of wind turbines, contradicting the commonly held assumption that windmills have no emissions during use. We show how to account for sound emissions in the life cycle inventory phase of the life cycle of a wind turbine and then calculate the relative impacts using a noise LCIA model.

Description: The article presents a method for the calculation of selected economy-wide material flow indicators (namely, direct material input [DMI] and raw material input [RMI]) for economic sectors. Whereas sectoral DMI was calculated using direct data from statistics, we applied a concept of total flows and a hybrid input-output life cycle assessment method to calculate sectoral RMI. We calculated the indicators for the Czech Republic for 2000–2011. We argue that DMI of economic sectors can be used for policies aiming at decreasing the direct input of extracted raw materials, and imported raw materials and products, whereas sectoral RMI can be better used for justifying support for or weakening the role of individual sectors within the economy. High-input material flows are associated in the Czech Republic with the extractive industries (agriculture and forestry, the mining of fossil fuels [FFs], other types of mining, and quarrying), with several manufacturing industries (manufacturing of beverages, basic metals, motor vehicles or electricity, and gas and steam supply) and with construction. Viable options for reducing inputs of agricultural biomass include changes in people's diet toward a lower amount of animal-based food and a decrease in the wasting of food. For FFs, one should think of changing the structure of total primary energy supply toward cleaner gaseous and renewable energy sources, innovations in transportation systems, and improvements in overall energy efficiency. For metal ores, viable options include technological changes leading to smaller and lighter products, as well as consistent recycling and use of secondary metals.

Description: By-product synergy is a growing practice worldwide. It consists in the maximization of resources utilization with the replacement of raw materials by by-products as inputs for industrial processes. In order to support decision making in such strategic projects, appropriate tools must be developed. This article presents the results of a research project, which includes the development of a multiobjective mathematical programming model for the optimization of by-product flows, synergy configurations, and investment decisions in eco-industrial networks. This model is evaluated using data related to the Kalundborg industrial symbiosis (IS) in order to illustrate its utilization, as well as to assess, in a retrospective manner, the behavior of the companies involved with respect to both economic and environmental benefits of synergies. The experiments also illustrate the influence of the municipality on synergy implementation and how a scenario-based approach can be used to anticipate raw material price increase. The results are generally coherent with the actual timing of synergy initializations. Further, the considerable effect of water price on the length of investments’ payback period illustrates the impact of policies and regulations on IS.

Description: Under an extended producer responsibility (EPR) system, when a producer delivers a product to the market it must also pay a takeback fee, which is used to cover the costs of end-of-life disposal. EPR systems are currently used in Europe and beyond to manage a variety of products, including packaging and used tires. In this article we develop an input-output (IO) model that is able to assess the impacts of an EPR system, and is based on the waste IO (WIO) model. The WIO model is itself a hybrid-unit model extension of the Leontief model that is able to capture the substitution effect between recycled/recovered material/energy from waste treatment and their non-waste cognates. The resulting EPRIO model, besides the conventional direct and indirect effects of the Leontief model and the substitution effects of the WIO model, is able to capture the opportunity costs of financing the EPR system, and additionally requires the specification of an alternative waste management policy, with its own opportunity costs. The impact of an EPR policy is thus the difference between the impacts of the reference EPR and the alternative waste treament policies. The resulting model is illustrated with a simple example of a used tire management EPR system.

Description: There is consensus on the importance of upstream methane (CH 4 ) emissions to the life cycle greenhouse gas (GHG) footprint of natural gas systems, but inconsistencies among recent studies explain why some researchers calculate a CH 4 emission rate of less than 1% whereas others calculate a CH 4 emission rate as high as 10%. These inconsistencies arise from differences in data collection methods, data collection time frames, and system boundaries. This analysis focuses on system boundary inconsistencies. Our results show that the calculated CH 4 emission rate can increase nearly fourfold not by changing the magnitude of any particular emission source, but by merely changing the portions of the supply chain that are included within the system boundary. Our calculated CH 4 emission rate for extraction through pipeline transmission is 1.2% for current practices. Our model allows us to identify GHG contributors in the upstream supply chain, but also allows us to tie upstream findings to complete life cycle scenarios. If applied to the life cycles of power systems and assessed in terms of cumulative radiative forcing, the upstream CH 4 emission rate can be as high as 3.2% before the GHG impacts from natural gas power exceed those from coal power at any point during a 100-year time frame.

Description: The use of water resources has traditionally been studied by accounting for the volume of water removed from sources for specific uses. This approach focuses on surface and groundwater only and it ignores that international trade of products with substantial amounts of embodied water can have an impact on domestic water resources. Using current economic and environmental data, we conduct a consumption-based assessment of virtual water flows in the European Union (EU27). We find that the total water footprint (WF) of 2,280 cubic meters (m 3 ) per capita for the EU27 mostly consists of green water use (precipitation stored as soil moisture), which is omitted in the conventional water accounting. Blue water (surface and groundwater.) and gray water use (the volume of freshwater needed to dilute pollutants to meet the applicable water quality standards), which are targeted by current EU water policies, only make up 32% of the total WF. We also find that Europeans imported 585 cubic kilometers (km 3 ) (10 9 m 3 ) of virtual water, or around 28% of global virtual water trade flows, in 2009. Within Europe, Germany is a key net importer of water through the trade of products in agriculture, the food industry, the chemical sector, and electricity generation. Countries in Southern and Eastern Europe have specialized in water-intensive agriculture and are key exporters of virtual water despite experiencing physical scarcity of water. Our results suggest that there is a need to reconsider water policy in the EU to address water transfers occurring through trade and to grasp the interlinkages between green, blue, and gray water—which are likely to become more important in water-scarce parts of Europe, with a changing climate.

Description: To revisit global net carbon dioxide (CO 2 ) emissions transfers by international trade for year 2007, this study employs a new world-wide, multiregional input-output (MRIO) table in which China's production is separated into domestic use, processing exports, and nonprocessing exports. The results show that processing exports in China involves relatively lower CO 2 emissions than other production types for the same output levels. Therefore, if processing exports are not appropriately distinguished, net CO 2 emission exports from China to other regions will be distorted; the relative bias occasionally reaches 15%. Net emission exports from regions other than China are also distorted, particularly for regions that use considerable Chinese processing exports as intermediates, such as the United States, European Union (EU), and East Asia. Given that processing exports prevail in a large number of developing countries, such as Mexico and Vietnam, one should carefully interpret measurements of net emission transfers by international trade by utilizing the ordinary world-wide MRIO model.

Description: Petroleum from unconventional reserves is making an increasingly important contribution to the transportation fuel supply, but is generally more expensive and has greater environmental burdens than petroleum from conventional sources. Life cycle assessments (LCAs) of alternative fuel-vehicle technologies typically consider conventional internal combustion engine vehicles fueled by gasoline produced from the average petroleum slate used in refineries as a baseline. Large-scale deployment of alternative fuel-vehicle technologies will decrease petroleum demand and lead to decreased production at the economic margin (unconventional oil), but this is not considered in most current LCAs. If marginal petroleum resources have larger impacts than average petroleum resources, the environmental benefits of petroleum demand reduction are underestimated by the current modeling approaches. Often, models include some consequential-based impacts (such as indirect land-use change for biofuels), but exclude others (such as avoided unconventional oil production). This approach is inconsistent and does not provide a robust basis for public policy and private investment strategy decisions. We provide an example to illustrate the potential scale of these impacts, but further research is needed to establish and quantify these marginal effects and incorporate them into LCAs of both conventional and alternative fuel-vehicle technologies.

Description: Environmentally extended input-output analysis is the prevailing method for national environmental footprint accounting; however, its practical usefulness for consumers and policy makers suffers from lack of detail. Several extensive global multiregional input-output (MRIO) databases have recently been released. A standard framework for linking such databases with the highly detailed household expenditure surveys that are conducted regularly by national statistics offices has the potential of providing analysts in countries worldwide with a powerful tool for in-depth analyses of their national environmental footprints. In this article, we combine the Norwegian consumer expenditure survey with a global MRIO database to assess the carbon footprint (CF) of Norwegian household consumption in 2012, as well as its annual development since 1999. We offer a didactic account of the practical challenges associated with the combination of these types of data sets and the approach taken here to address these, and we discuss what barriers still remain before such analyses can be practically conducted and provide reliable results. We find a CF of 22.3 tonnes of carbon dioxide equivalents per household in 2012, a 26% increase since 1999. Transport, housing, and food were the expenditures contributing the most toward the total footprint. CF per unit of expenditure increased with overall expenditure levels (elasticity: 1.14), notably owing to the correlation between overall household expenditure and transport activities (elasticity: 1.48). Household energy use, which is generally inelastic, is, in Norway, largely based on hydropower and hence contributes comparatively little to the overall expenditure elasticity of household CF.

Description: In recent years, the concepts of accounting for water use and assessing its impact, also known as the water footprint (WF), have evolved. The cultivation of wood and cotton are two important bio-based fiber resources that can use, consume, and pollute huge amounts of water. The purpose of this study is to identify the methodological options on an inventory level asociated with a WF assessment for bio-based fiber resources. Using a three-step Argument Delphi approach with international experts, important, but controversial, aspects of water footprinting are elaborated. During the different rounds of the Delphi procedure, the interlacement of the crucial topics became apparent, including the net green water or the total volume of green water, trade-offs between water use and land-use impacts, allocation of the green WF on ecosystem services, and nomination of a reference situation (e.g., potential natural vegetation). Further, this study evaluates whether the experts allowed generalizations about these methodological options. Finally, the agreement of experts on some generalized statements showed that such statements can be used legitimately as long as knowledge of the inventory methods and knowledge of production characteristics are carefully combined.

Description: The article investigates the factors that make businesses postpone integrating the performance dimension of sustainability in global agrifood supply chains. Based on literature-based conceptual reasoning, the article conceptualizes a double company lens distinguishing between substantial supply chain management and mere public relations endeavors as a major obstacle for businesses pursuing comprehensive supply chain performance in global agrifood chains. We point out that many supply chain performance attributes represent, in fact, credence attributes that cannot be verified by the consumer, hence entailing an information asymmetry between the company and its consumers. Rational business responses to this situation tend to focus on symbolic actions and communication efforts by means of sustainability reports and other brand-enhancing marketing tools that may be decoupled from substantial operations and supply chain improvements. The research propositions developed have partly been corroborated by a content analysis of annual and sustainability reports of four major agrifood companies (Nestlé, PepsiCo, Unilever, and Mondelez International). The conceptual arguments and empirical analysis presented in the article may serve as the basis for managers and academics to develop innovative inter- and intraorganizational business processes that reconcile trade-offs between various agrifood supply chain performance dimensions, thus pushing the performance frontier outward, and that provide the necessary transparency for overcoming the currently adverse setting of incentives inherent in the food production, processing, retailing, and consumption system.

Description: In electric arc furnaces (EAFs), different grades of steel scrap are combined to produce the targeted carbon steel quality. The goal of this study is to assess the influence of scrap quality on the recycling process and on the final product by investigating the effect of the scrap mix composition, and other inputs, for example, preheating energy, on the electricity demand of the melting process. A large industrial data set (empirical data set of ∼20,000 individual heats recorded during 2.5 years at a Swiss EAF site) is analyzed using linear regression. The influence of scrap grades on electricity demand are found to correlate strongly with their respective quality; specific electricity demand is up to 45% higher for low-quality scrap than for high-quality scrap. Given that chemical compositions of scrap grades are highly variable and often unknown, average concentrations are determined using linear regression with scrap input as the predictors and the amounts of the investigated elements in liquid steel as the dependent variable. The lowest quality (highest copper and tin concentrations) and the highest electricity demand in the EAF are found for scrap recovered from bottom ashes of municipal solid waste incineration. Although even with low-quality scrap input steel recycling is environmentally superior to primary steel production, the optimization potential in terms of energy efficiency and resource recovery, for example, through pretreatment, seems to be substantial.

Description: The production of goods and services generates greenhouse gases (GHGs) and air pollution both directly and through the activities of the supply chains on which they depend. The analysis of the latter—called embodied emissions—caused by internationally traded goods and services is the subject of this article. We find that trade openness increases embodied emissions in international trade (EET). We also examine the impact of sector trade on EET. By applying a fixed-effect model using large balanced panel data from 187 countries between 1990 and 2011, we determine that each unit of increase in trade openness results in a 10% to 23% increase in GHGs EET. The sector trade effect is also significant for the embodied emissions of carbon dioxide, methane, nitrous oxide, carbon monoxide, nonmethane volatile organic compounds, particulates and sulfur dioxide. Our findings also clearly indicate that the impact of the gross domestic product (GDP) on the embodied emissions in exports is positive, increasing emissions, but that it is negative on the embodied emissions in imports. We suggest that countries monitor trade sector emissions and trade openness to mitigate global embodied GHG emissions and air pollutants.

Description: Along with globalization, countries consume a large amount of goods and services from both domestic and international markets. As one of the world's largest agricultural countries, China is faced with serious water scarcity and has to reduce the water consumption from both domestic and global aspects, of which the crop planting structure optimization (CPSO) between regions based on the virtual water perspective could be a solution for efficient agricultural water consumption. In this article, three scenarios of Chinese agriculture, including agricultural water consumption restrictions relaxed scenario, agricultural water consumption limited scenario, and net utilization ratio of water resources limited scenario, were designed to minimize the national agricultural water consumption under various water, land, and crop planting constraints in individual provinces and analyze the impacts of the CPSO. The results showed that compared with the historical situation of crop planting in 2007, 53.3%, 51.4%, and 47.3% of the agricultural water consumption and more than 10% of the sown area of China was saved under the three scenarios, respectively. Because of the reduction of agricultural water consumption and land use, it brought about the expansion of crops production in China. CPSO is found to have notable effects on water saving and food security considering the dependence of the crops by international trade.

Description: Life cycle assessment (LCA) and urban metabolism (UM) are popular approaches for urban system environmental assessment. However, both approaches have challenges when used across spatial scales. LCA tends to decompose systemic information into micro-level functional units that mask complexity and purpose, whereas UM typically equates aggregated material and energy flows with impacts and is not ideal for revealing the mechanisms or alternatives available to reduce systemic environmental risks. This study explores the value of integrating UM with LCA, using vehicle transportation in the Phoenix metropolitan area as an illustrative case study. Where other studies have focused on the use of LCA providing upstream supply-chain impacts for UM, we assert that the broader value of the integrated approach is in (1) the ability to cross scales (from micro to macro) in environmental assessment and (2) establishing an analysis that captures function and complexity in urban systems. The results for Phoenix show the complexity in resource supply chains and critical infrastructure services, how impacts accrue well beyond geopolitical boundaries where activities occur, and potential system vulnerabilities.

Description: Bangladesh has emerged as a leading ship breaking nation. We conducted a material flow analysis of steel in Bangladesh with an emphasis on the ship breaking industry (SBI). The total aggregate domestic steel consumption in fiscal year (FY) 2010 was 2,930,000 tonnes (t) in Bangladesh; SBI met approximately 51% of the demand for raw materials and 37% of the demand for finished steel products. Rolling industries output in FY2010 was 1,451,000 t; 23% of the input for this production was from ship breaking sources. Dismantled ships also generate high-quality reusable steel scraps. SBI was found to be the sole source of scraps for small rerolling industries in Bangladesh, and their output in 2008 more than doubled as compared to 2005. Larger rolling industries fulfilled their input needs for steel scraps by using both SBI and imported materials. We found a sharp increase in input imports during the global ship breaking recession in 2003–2007 and when Bangladesh's SBI faced a temporary ban in 2010. Induction furnaces in Bangladesh in FY2010 produced a total of 787,000 t of billets; more than 40% was from ship-sourced scraps. In 2008, the country's steel consumption was 3,220,000 t, that is, 22 kilograms per person, and the intensity of steel use was 40 grams per U.S. dollar, which was much higher than that of other developing countries with a similar per capita gross domestic product (GDP). The country exhibited a high level of steel consumption relative to its GDP, which is indicative of the contribution of SBI.

Description: Russian forest resources are important for global carbon cycling. In contrast to traditional analyses that focus on the harvest and direct use of Russian timber resources (a.k.a. production-based accounting), this study investigates how the consumption of nations drives Russian timber harvest (a.k.a. consumption-based accounting or the Russian timber footprint). China is the biggest direct importer and final consumer of Russian timber. The United States, Japan, and major European countries directly import relatively small amounts of Russian timber, but serve to drive large amounts of Russian timber harvest through their final consumption. Through structural path analysis, individual supply chain paths are delineated to show linkages between Russian timber harvest and the final consumption of nations. Findings of this study inform consumption-side measures for Russian forest conservation, for example, taking shared responsibility and improving the production efficiency of key sectors in consuming nations.

Description: This article presents a model that quantifies the health loss and benefit triggered by the life cycle of a diesel engine. The health loss and benefit are expressed in the form of disability-adjusted life years (DALY), a metric used by the World Health Organization to conduct health impact assessments. In order to quantify the health loss, life cycle assessment methodology is applied. To estimate the health benefit, the relationship between DALY per capita and gross domestic product (GDP) per capita is modeled. The change in GDP per capita, resulting from the change in the level of employee compensation caused by the life cycle of the diesel engine, is used to estimate the change in the level of DALY per capita. An economic input-output model is applied to estimate the amount of employee compensation required over the life cycle of the diesel engine. This study concludes that the health benefit achieved by the socioeconomic growth, triggered by the life cycle of the diesel engine, is higher than the health loss caused by the pollutions produced over the life cycle of the diesel engine. Furthermore, the results support findings in the literature that socioeconomic growth generates a higher health benefit in a lower-income country than in a higher-income country. This also might be one of the reasons for another statement found in the literature that developing countries put higher priorities on economic development.

Description: Making the link between the different economic scales—local, regional, and global—and the impacts associated with more global behavior is a natural extension of traditional environmentally extended input-output (I-O) modeling. In this article, we highlight the capabilities of combining the meso level (i.e., regional) I-O models with geographical information systems (GIS) and micro data to lower the spatial scale. This methodology lets us provide information to municipalities (what we call the micro scale) on their water footprints (WFs) at a lower spatial level than that of Spanish regions (what we call meso scale), at which economic I-O data are available. Based on a multiregional I-O model for the Spanish regions, we analyze the local water impacts of tourism activity in Spain. We focus on the explicit spatial identification of areas of strong final demand (normally the most populated) tracking back the associated footprints to the original hotspots or vulnerable areas (micro scale), where most water withdrawal had taken place. The spatial divergence between the production and the consumption responsibilities arise because consumers and producers usually have very different characteristics, particularly with respect to tourism. We find highest geographic dispersion of WFs of consumption arising from domestic tourism, followed by domestic household consumption, and finally foreign tourism WF. Foreign tourism WF is more concentrated in time and space. Foreign tourism in Andalusia requires directly and indirectly (WF) 617 cubic hectometers (hm 3 ) and in Madrid 440 hm 3 , indicating that such tourism in both regions accounts for some of the highest water intensities per euro (€) spent by a foreign tourist, around 0.1 cubic meters/€.

Description: At the core of consequential life cycle assessment (CLCA) is a model of the economic system of which the activity that motivates the CLCA is a part. While there are several applications of CLCA in the literature, there does not appear to exist a formal, general mathematical framework. To address this gap, this article presents a general multi-market equilibrium framework, which could be adapted to an arbitrary level of complexity depending on the context and data availability. A general expression for total pollution (of a given type) is derived, which highlights different factors that determine the impact on emissions. It is then illustrated how microeconomic theory can help predict the direction of price and quantity changes for each commodity within the modeled system simply based on an activity's relationship to the ultimate activity or service, which motivates the CLCA. The steps involved in converting the multi-market framework to general equilibrium are also discussed.

Description: Several studies have examined the relationship between environmental degradation and population growth. However, most of them do not take into account the difference between local population and tourist arrivals, which is considerably important for mature tourist destinations. This article contributes to the literature by separating these two groups within the framework of IPAT-based models to measure the impact of tourist arrivals in terms of municipal solid waste generation for Mallorca. The model leads to a stochastic differential equations system, which shows that this mature tourist destination has higher population elasticity than industrial economies. Moreover, the model allowed us to measure the elasticity of substitution between lower- and higher-income tourists. Results showed that an increase of 1% on tourist arrivals growth rate would generate an increase in waste disposal generation of 1.25%. Furthermore, an increase of tourist expenditures by 1% on the destination would lead to an increase of municipal solid waste generation of 0.51%.

Description: Battery electric motorcycles offer the potential to reduce greenhouse gas emissions and fossil fuel consumption in road transportation, but result in problem shifting when considering potential environmental impacts during vehicle production and disposal. This study evaluates the life cycle environmental impacts of implementing lithium-ion and lead-acid battery electric motorcycles in Thailand's motorcycle fleet to meet the government's motorcycle energy reduction target of 2,791 kilotonnes oil equivalent, compared to conventional motorcycles. A stock-turnover model is used to determine the market growth of electric motorcycles on the fleet from 2015 to 2030 to meet the energy reduction target. The total costs of ownership of each motorcycle are analyzed on a single vehicle basis to compare the cost benefits. The results of the study reveal that the environmental performance of an electric motorcycle fleet is sensitive to variations in use-phase energy consumption, the electricity mix consumed, and battery disposal scenarios. Realization of Thailand's Power Development Plan can reduce total impacts of the electric motorcycle fleet to global warming by 6% to 10%. It is crucial that batteries from electric motorcycles are recycled to avoid 98% of impacts to toxicity. Lead-acid battery electric motorcycles are a more affordable option for consumers in Thailand compared to conventional motorcycles and lithium-ion battery electric motorcycles. Recommendations are made to improve the environmental performance of electric motorcycle implementation strategies in Thailand.

Description: Food consumption is a local activity related to environmental impacts at different scales. Yet, the link between eating food as a social and cultural practice and the global implications of food consumption has not been sufficiently explored. We adopt a multidisciplinary approach to relate social practices with the biophysical flows of food products at the household level. Focusing on middle-class households in Metro Manila, the Philippines, we conduct qualitative interviews to highlight preferences, habits, and perceptions about food consumption. In parallel, we collect quantitative information on food purchased. We relate our results to national trends by analyzing the recent evolution of national food expenditures. Finally, we review environmental impacts related to main food categories. Our research points to the significance of socioeconomic factors on food consumption, notably the presence of domestic help or the professional situation of household members. One main finding is the identification of eating out as an important and growing trend in Asian cities, which causes a shift of resource consumption and related environmental impacts from the household to the service sector.

Description: This study investigates the prevailing practice of obtaining single scores in life cycle assessment (LCA) and identifies potential lacunas in impact assessment methodology related to the results of aggregation into endpoints and single scores. In order to conduct this investigation, a detailed approach was adopted to facilitate identification of three main problems related to the single-score calculation approach. The prevailing ReCiPe single-score calculation method does not account for either the effect of so-called dominating alternatives (i.e., alternatives having high values across all endpoints) or the interdependency of the indicators being aggregated. It was also found that the simple linear weighted sum method, presently used for obtaining single scores, is not capable of accounting for the effect of weighting schemes and thus cannot realistically represent stakeholders’ perspectives. Finally, we propose a distance-based multiple attribute decision-making method for use in obtaining single scores. This method was found to be more suitable, given that it takes into account the weighting schemes and types of indicators in the process of estimating single scores. The new single-score calculation method proposed here is considered ideal for environmental decision-making problems in the context of life cycle sustainability assessment. Thus, it is also ideal for situations in which more-complex decision-making situations will emerge by combining LCA indicators (midpoints or endpoints) with other indicators representing the performance of a system from economic and social perspectives.

Description: This article sets out an approach to researching sociocultural aspects of product service systems (PSSs) consumption in consumer markets. PSSs are relevant to industrial ecology given that they may form part of the mix of innovations that move society toward more-sustainable material and energy flows. The article uses two contrasting case studies drawing on ethnographic analysis: Harley Davidson motorcycles and the Zipcar car club. The first is a case of consumption involving ownership; the second is one of consumption without ownership. The analysis draws on consumer culture theory to explicate the sociocultural, experiential, symbolic, and ideological aspects of these case studies, focusing on product ownership. The article shows that ownership of Harley Davidson motorcycles enables riders to identify with a brand community and to define themselves. Owners appropriate their motorcycles through customization. In contrast, Zipcar users resist the company's attempts to involve them in a brand community, see use of car sharing as a temporary fix, and even fear contamination from shared use of cars. We conclude that iconic products such as Harley Davidson motorcycles create emotional attachment and can challenge PSS propositions. But we also suggest that somewhat standardized products may present similar difficulties. Knowing more about sociocultural aspects of PSSs may help designers overcome these difficulties.

Description: This study looks into material flow trends in the Philippines from 1985 to 2010 by utilizing the methodology of economy-wide material flow analysis. Using domestic data sources, this study presents disaggregated annual material flow trends in terms of four major material categories, namely: biomass; fossil energy carriers; ores and industrial minerals; and construction minerals. The results describe in detail the growth of material flows in a high-density country at the onset of its development and reveal the shift of material consumption from dominance of renewable materials in 1985 to nonrenewable materials in 2010. IPAT analysis shows that the increase in material consumption was driven by population growth from 1985 to 1998 and by growth in affluence from 1999 to 2010. However, high inequalities amidst the growing economy suggest that a small group of wealthy people have influenced the acceleration of material consumption in the Philippines. The results of this research are intended to provide a thorough analysis of the processes occurring in Philippine economic growth in order to assist in tackling implications for the important issue of sustainable resource management.

Description: Emerging economies such as China and India are currently experiencing a “refrigeration revolution.” Energy spent for domestic cooling is expected to outreach that for heating worldwide over the course of the twenty-first century. Magnetic refrigeration is an alternative cooling technology that works without gas-based refrigerants and has the potential to be significantly more energy efficient. We evaluate to what extent the raw materials needed to produce this kind of technology on a mass-market scale are critical in terms of demand and supply, thus identifying potential supply bottlenecks that might hinder the breakthrough of this promising technology. We assess the criticality of three promising magnetocaloric materials, that is, Gd 5 (SiGe) 4 , La(FeSi) 13 , and (MnFe) 2 P), as well as of Nd 2 Fe 14 B, as the candidate permanent magnet material to drive the cooling cycle. The Gd-based alloys are disqualified as a mass-market refrigerant in terms of resource criticality, whereas La- and Mn-based alloys are much less problematic. Given the current state of technology and projected resource supply, Nd in Nd 2 Fe 14 B magnets would experience a significant bottleneck only at a later innovation stage, that is, when magnetic cooling technology would largely dominate the domestic refrigerator and air-conditioning market.

Description: Sustainable use of wood may contribute to coping with energy and material resource challenges. The goal of this study is to increase knowledge of the environmental effects of wood use by analyzing the complete value chain of all wooden goods produced or consumed in Switzerland. We start from a material flow analysis of current wood use in Switzerland. Environmental impacts related to the material flows are evaluated using life cycle assessment–based environmental indicators. Regarding climate change, we find an overall average benefit of 0.5 tonnes carbon dioxide equivalent per cubic meter of wood used. High environmental benefits are often achieved when replacing conventional heat production and energy-consuming materials in construction and furniture. The environmental performance of wood is, however, highly dependent on its use and environmental indicators. To exploit the mitigation potential of wood, we recommend to (1) apply its use where there are high substitution benefits like the replacement of fossil fuels for energy or energy-intensive building materials, (2) take appropriate measures to minimize negative effects like particulate matter emissions, and (3) keep a systems perspective to weigh effects like substitution and cascading against each other in a comprehensive manner. The results can provide guidance for further in-depth studies and prospective analyses of wood-use scenarios.

Description: This work contributes to the development of a dynamic life cycle assessment (DLCA) methodology by providing a methodological framework to link a dynamic system modeling method with a time-dependent impact assessment method. This three-step methodology starts by modeling systems where flows are described by temporal distributions. Then, a temporally differentiated life cycle inventory (TDLCI) is calculated to present the environmental exchanges through time. Finally, time-dependent characterization factors are applied to the TDLCI to evaluate climate-change impacts through time. The implementation of this new framework is illustrated by comparing systems producing domestic hot water (DHW) over an 80-year period. Electricity is used to heat water in the first system, whereas the second system uses a combination of solar energy and gas to heat an equivalent amount of DHW at the same temperature. This comparison shows that using a different temporal precision (i.e., monthly vs. annual) to describe process flows can reverse conclusions regarding which case has the best environmental performance. Results also show that considering the timing of greenhouse gas (GHG) emissions reduces the absolute values of carbon footprint in the short-term when compared with results from the static life cycle assessment. This pragmatic framework for the implementation of time in DLCA studies is proposed to help in the development of the methodology. It is not yet a fully operational scheme, and efforts are still required before DLCA can become state of practice.

Description: Dynamic material flow analysis (MFA) provides information about material usage over time and consequent changes in material stocks and flows. In order to understand the effect of limited data quality and model assumptions on MFA results, the use of sensitivity analysis methods in dynamic MFA studies has been on the increase. So far, sensitivity analysis in dynamic MFA has been conducted by means of a one-at-a-time method, which tests parameter perturbations individually and observes the outcomes on output. In contrast to that, variance-based global sensitivity analysis decomposes the variance of the model output into fractions caused by the uncertainty or variability of input parameters. The present study investigates interaction and time-delay effects of uncertain parameters on the output of an archetypal input-driven dynamic material flow model using variance-based global sensitivity analysis. The results show that determining the main (first-order) effects of parameter variations is often sufficient in dynamic MFA because substantial effects attributed to the simultaneous variation of several parameters (higher-order effects) do not appear for classical setups of dynamic material flow models. For models with time-varying parameters, time-delay effects of parameter variation on model outputs need to be considered, potentially boosting the computational cost of global sensitivity analysis. Finally, the implications of exploring the sensitivities of model outputs with respect to parameter variations in the archetypical model are used to derive model- and goal-specific recommendations on choosing appropriate sensitivity analysis methods in dynamic MFA.

Description: The environmental impacts of data centers that provide information and communication technologies (ICTs) services are strongly related to electricity generation. With the increasing use of ICT, many data centers are expected to be built, causing more absolute impacts on the environment. Given that electricity distribution networks are very complex and dynamic systems, an environmental evaluation of future data centers is uncertain. This study proposes a new approach to investigate the consequences of future data center deployment in Canada and optimize this deployment based on the Energy 2020 technoeconomic model in combination with life cycle assessment methodology. The method determines specific electricity sources that will power the future Canadian data centers and computes related environmental impacts based on several indicators. In case-study scenarios, the largest deployment of data centers leads to the smallest impact per megawatt of data centers for all of the environmental indicators. It is found that an increase in power demand by data centers would lead to a reduction in electricity exports to the United States, driving the United States to generate more electricity to meet its energy demand. Given that electricity generation in the United States is more polluting than in Canada, the deployment of data centers in Canada is indirectly linked to an increase in overall environmental impacts. However, though an optimal solution should be found to mitigate global greenhouse gas emissions, it is not clear whether the environmental burden related to U.S. electricity generation should be attributed to the Canadian data centers.

Description: The life cycle environmental profile of energy-consuming products, such as air conditioning, is dominated by the products’ use phase. Different user behavior patterns can therefore yield large differences in the results of a cradle-to-grave assessment. Although this variation and uncertainty is increasingly recognized, it remains often poorly characterized in life cycle assessment (LCA) studies. Today, pervasive sensing presents the opportunity to collect rich data sets and improve profiling of use-phase parameters, in turn facilitating quantification and reduction of this uncertainty in LCA. This study examined the case of energy use in building cooling systems, focusing on global warming potential (GWP) as the impact category. In Singapore, building cooling systems or air conditioning consumes up to 37% of national electricity demand. Lack of consideration of variation in use-phase interaction leads to the oversized designs, wasted energy, and therefore reducible GWP. Using a high-resolution data set derived from sensor observations, energy use and behavior patterns of single-office occupants were characterized by probabilistic distributions. The interindividual variability and use-phase variables were propagated in a stochastic model for the life cycle of air-conditioning systems and simulated by way of Monte Carlo analysis. Analysis of the generated uncertainties identified plausible reductions in global warming impact through modifying user interaction. Designers concerned about the environmental profile of their products or systems need better representation of the underlying variability in use-phase data to evaluate the impact. This study suggests that data can be reliably provided and incorporated into the life cycle by proliferation of pervasive sensing, which can only continue to benefit future LCA.

Description: Estimates of the climate-change mitigation benefits of biofuels are varied and controversial. Some analysts rely on attributional life cycle assessment (ALCA), limiting the analytic scope to the direct supply chain, whereas others supplement an ALCA result with an estimate of land-use change (LUC) emissions intensity. Other analysts have used consequential life cycle assessment (CLCA), with methods ranging from static market assessments to identify the likely marginal product and supplier, to running partial and general equilibrium models to estimate changes in global production and consumption. In this article, we consider another alternative—using an integrated assessment model (IAM) as a platform for CLCA of biofuels. In this article (part I of II), we focus on the methodological challenges of this approach. In part II, we present a case study using one IAM—the global change assessment model (GCAM)—to estimate the climate effects of several biofuels.

Description: Table of Contents Title Page Editorial Board Aims and Scope

Description: A material flow analysis of the 2012 Swiss waste management system is presented, highlighting the material content available from waste. Half of municipal solid waste (MSW) is materially recycled and the other half thermally treated with energy recovery. A key component of an industrial ecosystem is increasing the resource efficiency through circulating materials. Recycling rates (RRs), an indicator for the circulating behavior of materials, are often used as measure for the degree of circularity of an economy. This study provides an in-depth analysis of the recycling of paper, cardboard, aluminum, tinplate, glass, and polyethylene terephthalate (PET) from MSW in Switzerland by splitting the RRs into closed- and open-loop collection rate (CR) and RRs. Whereas CR refers to collected material that enters the recycling process, RRs measure the available secondary resources produced from recycling processes. For PET, the closed-loop CR of 45% and the open-loop CR of 40% compare to an RR of 31% and 37%, respectively (including exports and recycling of polyethylene and metals from collection). Official collection rates for paper and cardboard are very high (97%), whereas CR of 74% and 89% and RR of 59% and 81% for paper and cardboard, respectively, were found in the present study (including export). For a majority of the separately collected materials investigated, the rates that are determined are substantially lower than those that are officially communicated. Furthermore, given that official rates often do not provide information on the availability of secondary materials, the improvement potential for increased resource recovery is hidden.

Description: Table of Contents Title Page Editorial Board Aims and Scope

Description: In the ongoing debate about the climate benefits of fuel switching from coal to natural gas for power generation, the metrics used to model climate impacts may be important. In this article, we evaluate the life cycle greenhouse gas emissions of coal and natural gas used in new, advanced power plants using a broad set of available climate metrics in order to test for the robustness of results. Climate metrics included in the article are global warming potential, global temperature change potential, technology warming potential, and cumulative radiative forcing. We also used the Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) climate-change model to validate the results. We find that all climate metrics suggest a natural gas combined cycle plant offers life cycle climate benefits over 100 years compared to a pulverized coal plant, even if the life cycle methane leakage rate for natural gas reaches 5%. Over shorter time frames (i.e., 20 years), plants using natural gas with a 4% leakage rate have similar climate impacts as those using coal, but are no worse than coal. If carbon capture and sequestration becomes available for both types of power plants, natural gas still offers climate benefits over coal as long as the life cycle methane leakage rate remains below 2%. These results are consistent across climate metrics and the MAGICC model over a 100-year time frame. Although it is not clear whether any of these metrics are better than the others, the choice of metric can inform decisions based on different societal values. For example, whereas annual temperature change reported may be a more relevant metric to evaluate the human health effects of increased heat, the cumulative temperature change may be more relevant to evaluate climate impacts, such as sea-level rise, that will result from the cumulative warming.

Description: This study compares U.S. and Japanese consumers’ perceptions of remanufactured auto parts. Remanufactured parts have a long history and enjoy continuing success in the U.S. domestic aftermarket. In contrast, although Japan's domestic aftermarket is growing, it remains comparatively underdeveloped. This research examines whether customers’ perceptions of remanufactured products explain their lower acceptance in Japan. Our Internet survey of 440 U.S. and 300 Japanese respondents examined their knowledge of remanufactured auto parts, perceptions of their benefits and risks, and price consciousness. The results reveal that Japanese consumers know less about remanufactured products, perceiving them as entailing lower benefits and greater risk, especially concerning quality, and are less price conscious. Drawing on its results, this study suggests measures to promote markets for remanufactured auto parts in Japan and in economies in which such markets are in an early stage of development.

Description: Additive manufacturing that creates three-dimensional objects by adding layer upon layer of material is a new technique that has proven to be an excellent tool for the manufacturing of complex structures for a variety of industrial sectors. Today, knowledge regarding particle emissions and potential exposure-related health hazards for the operators is limited. The current study has focused on particle numbers, masses, sizes, and identities present in the air during additive manufacturing of metals. Measurements were performed during manufacturing with metal powder consisting essentially of chromium, nickel, and cobalt. Instruments used were Nanotracer (10 to 300 nanometers [nm]), Lighthouse (300 nm to 10 micrometers), and traditional filter-based particle mass estimation followed by inductively coupled plasma mass spectrometry. Results showed that there is a risk of particle exposure at certain operations and that particle sizes tended to be smaller in recycled metal powder compared to new. In summary, nanosized particles were present in the additive manufacturing environment and the operators were exposed specifically while handling the metal powder. For the workers’ safety, improved powder handling systems and measurement techniques for nanosized particles will possibly have to be developed and then translated into work environment regulations. Until then, relevant protective equipment and regular metal analyses of urine is recommended.