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This study explores the prospects of urban mining for a steadily developing city "Thane," located in the Mumbai Metropolitan Region of India, through building material stock accounting (BMSA). A novel bottom‐up approach for stock accounting was developed for the cities with limited data availability, through the integration of geodata spatial analysis, archetype identification through statistical modeling, and regional building design assessment for material intensity calculation. This study is the first of its kind in the Indian context and focuses on the stock estimation of the most common building materials: concrete, reinforcement steel, and masonry bricks within the boundaries of a typical Indian urban area. The results showed that the total built‐up stock in Thane city in 2018 amounts to 84.7 million metric ton (MT) by weight; concrete 57.7%, bricks 40.4%, steel 1.9%. Such reservoirs of raw material can be harnessed to fulfill the future material requirements of the construction industry through proposed circular economy interventions such as material bank creation, local recycling facilities, and development of a secondary material market. The material stock estimated in this study was 46.1 MT/capita for permanent building dwellers and with potential infrastructural developments underway, urban mining application can be ensured by redefining design and demolition strategies and multi‐level collaboration for generating alternative material sources for the construction sector. This work of BMSA intends to provide meaningful insights into exploring the potentials of urban mining and help chart the future roadmaps of sustainable construction in India. [ABSTRACT FROM AUTHOR]

Summary: This synthesis article presents an overview of an urban metabolism (UM) approach using mixed methods and multiple sources of data for Los Angeles, California. We examine electric energy use in buildings and greenhouse gas emissions from electricity, and calculate embedded infrastructure life cycle effects, water use and solid waste streams in an attempt to better understand the urban flows and sinks in the Los Angeles region (city and county). This quantification is being conducted to help policy-makers better target energy conservation and efficiency programs, pinpoint best locations for distributed solar generation, and support the development of policies for greater environmental sustainability. It provides a framework to which many more UM flows can be added to create greater understanding of the study area's resource dependencies. Going forward, together with policy analysis, UM can help untangle the complex intertwined resource dependencies that cities must address as they attempt to increase their environmental sustainability.

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. [ABSTRACT FROM AUTHOR]

Urban metabolism provides a framework to understand resource flows into cities and waste flows out. Its potential has been hampered by the lack of good disaggregated data. This article presents energy-use findings for the residential sector for the city of Los Angeles based on census-block-level aggregation of address-level electricity use obtained from the Los Angeles Department of Water and Power. City or county billing data by customer class over time can enable empirical tracking of energy conservation and efficiency programs by different customer classes, and matched to census information and county tax assessor data about building vintage, size, and type can provide information important for rate setting, for example, or energy conservation and efficiency program investments. We report on median electricity demand and corresponding greenhouse gas emissions and expenditures at three geographical aggregations: city council district (15 in total); neighborhood (114 in total); and census block group (2,538 in total). We find that the ratio of median annual demand between highest- and lowest-tier users is 26 at the census-block group level, but only 2.2 at the city council district level, demonstrating that spatial aggregation significantly masks the degree of variation that may be observed. We also show how such data can enable the description of energy to develop energy disclosure thresholds that reflect a city's morphology. In contrast to New York City's 50,000-square-foot reporting threshold, to capture half of Los Angeles' electricity consumption, the threshold for reporting would have to be 5,000 square feet. [ABSTRACT FROM AUTHOR]

For half a century, system scientists have relied on urban metabolism (UM) as a pragmatic framework to support the needed transition toward sustainable urban development. It has been suggested that information and communication technology (ICT) and, more specifically, smart cities can be leveraged in this transition. Given the recent advances in smart cities, smart urban metabolism (SUM) is considered a technology-enabled evolution of the UM framework, overcoming some of its current limitations. Most significantly, the SUM framework works at high temporal (up to real-time) and spatial (down to household/individual) resolutions. This article presents the first implementation of SUM in the Smart City Stockholm Royal Seaport R&D project; it further analyzes barriers and discusses the potential long-term implications of the findings. Four key performance indicators (KPIs) are generated in real time based on the integration of heterogeneous, real-time data sources. These are kilowatt-hours per square meter, carbon dioxide equivalents per capita, kilowatt-hours of primary energy per capita, and share of renewables percentage. These KPIs are fed back on three levels (household, building, and district) on four interfaces, developed for different audiences. The most challenging barrier identified was accessing and integrating siloed data from the different data owners (utilities, building owners, and so forth). It is hard to overcome unless a significant value is perceived. A number of long-term opportunities were described in the SUM context; among those, it is envisioned that SUM could enable a new understanding of the causalities that govern urbanism and allow citizens and city officials to receive feedback on the system consequences of their choices. [ABSTRACT FROM AUTHOR]

Building stocks constitute enduring components of urban infrastructure systems, but little research exists on their residence time or changing environmental impacts. Using Los Angeles County, California, as a case study, a framework is developed for assessing the changes of building stocks in cities (i.e., a generalizable framework for estimating the construction and deconstruction rates), the residence time of buildings and their materials, and the associated embedded environmental impacts. In Los Angeles, previous land-use decisions prove not easily reversible, and past building stock investments may continue to constrain the energy performance of buildings. The average age of the building stock has increased steadily since 1920 and more rapidly after the post-World War II construction surge in the 1950s. Buildings will likely endure for 60 years or longer, making this infrastructure a quasi-permanent investment. The long residence time, combined with the physical limitations on outward growth, suggest that the Los Angeles building stock is unlikely to have substantial spatial expansion in the future. The construction of buildings requires a continuous investment in material, monetary, and energetic resources, resulting in environmental impacts. The long residence time of structures implies a commitment to use and maintain the infrastructure, potentially creating barriers to an urban area's ability to improve energy efficiency. The immotility of buildings, coupled with future environmental goals, indicates that urban areas will be best positioned by instituting strategies that ensure reductions in life cycle (construction, use, and demolition) environmental impacts. [ABSTRACT FROM AUTHOR]

This research reports on a multivariate analysis that examined the relationship between direct greenhouse gas (GHG) emissions and socioeconomic and well-being variables for 1,920 respondents living in Halifax Regional Municipality, Nova Scotia, Canada, using results from the Halifax Space-Time Activity Research Project. The unique data set allows us to estimate direct GHG emissions with an unprecedented level of specificity based on household energy use survey data and geographic positioning system-verified personal travel data. Of the variables analyzed, household size, income, community zone, age, and marital status are all statistically significant predictors of direct GHG emissions. Birthplace, ethnicity, educational attainment, perceptions of health, life satisfaction, job satisfaction, happiness, volunteering, or community belonging did not seem to matter. In addition, we examined whether those reporting energy-efficient behaviors had lower GHG emissions. No significant differences were discovered among the groups analyzed, supporting a growing body of research indicating a disconnect between environmental attitudes and behaviors and environmental impact. Among the predictor variables, those reporting to be married, young, low income, and living in households with more people have correspondingly lower direct GHG emissions than other categories in respective groupings. Our finding that respondents with lifestyles that generate higher GHG emissions did not report to be healthier, happier, or more connected to their communities suggest that individuals can experience similar degrees of well-being regardless of the amount of GHG emissions associated with his or her respective lifestyle. [ABSTRACT FROM AUTHOR]

Cities and urban regions are undertaking efforts to quantify greenhouse (GHG) emissions from their jurisdictional boundaries. Although inventorying methodologies are beginning to standardize for GHG sources, carbon sequestration is generally not quantified. This article describes the methodology and quantification of gross urban carbon sinks. Sinks are categorized into direct and embodied sinks. Direct sinks generally incorporate natural process, such as humification in soils and photosynthetic biomass growth (in urban trees, perennial crops, and regional forests). Embodied sinks include activities associated with consumptive behavior that result in the import and/or storage of carbon, such as landfilling of waste, concrete construction, and utilization of durable wood products. Using methodologies based on the Intergovernmental Panel on Climate Change 2006 guidelines (for direct sinks) and peer-reviewed literature (for embodied sinks), carbon sequestration for 2005 is calculated for the Greater Toronto Area. Direct sinks are found to be 317 kilotons of carbon (kt C), and are dominated by regional forest biomass. Embodied sinks are calculated to be 234 kt C based on one year's consumption, though a complete life cycle accounting of emissions would likely transform this sum from a carbon sink to a source. There is considerable uncertainty associated with the methodologies used, which could be addressed with city-specific stock-change measurements. Further options for enhancing carbon sink capacity within urban environments are explored, such as urban biomass growth and carbon capture and storage. [ABSTRACT FROM AUTHOR]

Urban metabolism studies have been established for only a few cities worldwide, and difficulties obtaining adequate statistical data are universal. Constraints and peculiarities call for innovative methods to quantify the materials entering and leaving city boundaries. Such methods include the extrapolation of data at the country or the region level based, namely, on sales, population, commuters, workers, and waste produced. The work described in this article offers a new methodology developed specifically for quantifying urban material flows, making possible the regular compilation of data pertinent to the characterization of a city's metabolism. This methodology was tested in a case study that characterized the urban metabolism of the city of Lisbon by quantifying Lisbon's material balance for 2004. With this aim, four variables were characterized and linked to material flows associated with the city: absolute consumption of materials/products per category, throughput of materials in the urban system per material category, material intensity of economic activities, and waste flows per treatment technology. Results show that annual material consumption in Lisbon totals 11.223 million tonnes (20 tonnes per capita), and material outputs sum 2.149 million tonnes. Nonrenewable resources represent almost 80% of the total material consumption, and renewables consumption (biomass) constitutes only 18% of the total consumption. The remaining portion is made up of nonspecified materials. A seemingly excessive consumption amount of nonrenewable materials compared to renewables may be the result of a large investment in building construction and a significant shift toward private car traveling, to the detriment of public transportation. [ABSTRACT FROM AUTHOR]

This section presents abstracts of articles published within the issue including "Companies on the Scale: Comparing and Benchmarking the Sustainability Performance of Businesses," "Urban Metabolism: Material Flow Accounting Based on the Lisbon Case Study," and "Environmental Impact and Intensity of Processes in Selected Services Companies."