Leonardo Rosado

Urban Metabolism: Methodological Advances in Urban Material Flow Accounting Based on the Lisbon Case Study

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 citys metabolism. This methodology was tested in a case study that characterized the urban metabolism of the city of Lisbon by quantifying Lisbons 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.

A Material Flow Accounting Case Study of the Lisbon Metropolitan Area Using the Urban Metabolism Analyst Model

Summary: This article describes a new methodological framework to account for urban material flows and stocks, using material flow accounting (MFA) as the underlying method. The proposed model, urban metabolism analyst (UMAn), bridges seven major gaps in previous urban metabolism studies: lack of a unified methodology; lack of material flows data at the urban level; limited categorizations of material types; limited results about material flows as they are related to economic activities; limited understanding of the origin and destination of flows; lack of understanding about the dynamics of added stock; and lack of knowledge about the magnitude of the flow of materials that are imported and then, to a great extent, exported. To explore and validate the UMAn model, a case study of the Lisbon Metropolitan Area was used. An annual time series of material flows from 2003 to 2009 is disaggregated by the model into 28 material types, 55 economic activity categories, and 18 municipalities. Additionally, an annual projection of the obsolescence of materials for 2010-2050 was performed. The results of the case study validate the proposed methodology, which broadens the contribution of existing urban MFA studies and presents pioneering information in the field of urban metabolism. In particular, the model associates material flows with economic activities and their spatial location within the urban area.

Uncertainty in Material Flow Analysis Indicators at Different Spatial Levels

Material flow analysis (MFA) is a tool for research and decision support in environmental policy and management. In order to promote the use of MFA at different spatial scales, a quantification of the uncertainty in nationwide, regional, and urban MFA methodologies is provided. In particular, the impact of the input data quality on the main MFA indicators is analyzed and the sources and extent of uncertainties for different spatial scales are listed. The types, origin, and extent of the errors are described in detail and several imputation methods are explained and evaluated. By introducing a novel approach to account measurement errors in data sets with very few details on the measurement errors, this article aims at contributing to the development of a standardized method to account for the uncertainty in MFA studies. This study uses the time series of MFA data for 1996-2011 at three spatial scalesnationwide (Sweden), regional (the Stockholm Region), and metropolitan (Stockholm, Gothenburg, and Malmo)to determine how propagation of measurement errors affects the MFA results. The following MFA indicators were studied: direct material input; domestic processed output; and domestic material consumption. Generally, availability decreased as the spatial scale was lowered, whereas data errors increased. In the specific case of Sweden, the data on freight transport by rail and on waste produced by economic activities at the regional and metropolitan level should be improved.

Out with the old, out with the new – The effect of transitions in TVs and monitors technology on consumption and WEEE generation in Sweden 1996–2014

The recycling of Waste Electrical and Electronic Equipment (WEEE) is important due to its content of valuable and hazardous compounds. This study investigates the case of the recent technology change within television sets (TVs) and monitors, its impact on the generation of WEEE, and the implications for the recycling industry. In particular, material flow analysis for the time series of 1996-2014 for TVs and monitors by type of technology (CRT, Plasma and LCD) in physical units is combined with empirical data on product lifespans. The number of consumed TVs and monitors has grown exponentially. As a result, despite a 3-fold reduction in the weight of the products, the weight of the corresponding WEEE is also growing exponentially. Out with the old, out with the new - a peak in WEEE from both CRT and flat-screen displays is expected during 2014-2020, due to the simultaneous obsolesce of the last wave of CRT products and the short-lived flat-screen products that substituted the CRTs. The lifespans of LCD and LED TVs were found to be three times shorter than of the CRT TVs, with many TVs discarded while still functional. This is the consequence of two events - replacement of the CRT TVs in combination with lifestyle purchases of TVs, i.e. the premature replacement of flat-screen displays with new sets with extra-large screens and/or new features. The throughput of TVs and monitors consumed has been estimated annually from 2014 until 2040, by quantity and type of device, as well as by component and material type. The annual economic value of the corresponding secondary materials, by material type, has also been estimated. The point in time when the final disposal of CRT products is likely to take place has been identified and should be noted by the recycling industry. Among the important contributions of this study to the accounting and predicting of amounts and types of WEEE are the lifespan distributions, size and weight distributions, and material composition for TVs and monitors of different technology. Directions for method application in other countries are given.

Urban Economies Resource Productivity and Decoupling: Metabolism Trends of 1996-2011 in Sweden, Stockholm, and Gothenburg

Resource productivity and evidence of economic decoupling were investigated on the basis of the time series in 1996-2011 of material flow analysis for Sweden, Stockholm, and Gothenburg. In the three cases, absolute reductions in CO2 emissions by about 20% were observed, energy consumption per capita decreased, while gross domestic product (GDP) per capita grew. The energy consumption of the residential and public sectors decreased drastically, while the transport energy consumption is still growing steadily. Decoupling of the economy as a whole (i.e., including materials) is not yet happening at any scale. The domestic material consumption (DMC) continues to increase, in parallel with the GDP. The rate of increase for DMC is slower than that for GDP in both Stockholm and Sweden as a whole (i.e., relative decoupling). The metabolism of the cities does not replicate the national metabolism, and the two cities each have their own distinct metabolism profiles. As a consequence, policy implications for each of the case studies were suggested. In general, because of the necessarily different roles of the two cities in the national economy, generic resource productivity benchmarks, such as CO2 per capita, should be avoided in favor of sectorial benchmarks, such as industry, transport, or residential CO2 per capita. In addition, the share of the city impacts caused by the provision of a service for the rest of the country, such as a port, could be allocated to the national economy.

Primary and secondary battery consumption trends in Sweden 1996-2013: Method development and detailed accounting by battery type

In this article, a new method based on Material Flow Accounting is proposed to study detailed material flows in battery consumption that can be replicated for other countries. The method uses regularly available statistics on import, industrial production and export of batteries and battery-containing electric and electronic equipment (EEE). To promote method use by other scholars with no access to such data, several empirically results and their trends over time, for different types of batteries occurrence among the EEE types are provided. The information provided by the method can be used to: identify drivers of battery consumption; study the dynamic behavior of battery flows - due to technology development, policies, consumers behavior and infrastructures. The method is exemplified by the study of battery flows in Sweden for years 1996-2013. The batteries were accounted, both in units and weight, as primary and secondary batteries; loose and integrated; by electrochemical composition and share of battery use between different types of EEE. Results show that, despite a fivefold increase in the consumption of rechargeable batteries, they account for only about 14% of total use of portable batteries. Recent increase in digital convergence has resulted in a sharp decline in the consumption of primary batteries, which has now stabilized at a fairly low level. Conversely, the consumption of integrated batteries has increased sharply. In 2013, 61% of the total weight of batteries sold in Sweden was collected, and for the particular case of alkaline manganese dioxide batteries, the value achieved 74%.

An Approach to Identify Resource Patterns on a Neighborhood Level

Resource stock and flow accounting has been increasingly applied on a country and city level. This paper elaborates on the possibilities to conduct a resource flow analysis even on a neighborhood/district level to identify, e.g., resource use related characteristics. Such resource patterns can be used to identify areas in different parts of a country or even larger geographical regions that are characterized by comparable types and amounts of resources entering the system boundaries. This identification might lead to archetypes that will help in deriving and applying policies, resource optimization strategies, etc. The approach presented in this paper stems from experiences made in the field of building stock modelling where archetypes are frequently used to characterize building stocks of a city or even a portfolio within a city. Furthermore, this approach is applied to develop energy and climate strategies for cities, renovation and maintenance strategies for real estate owners including investment planning. This paper reveals the shortcomings as well as the possibilities of resource pattern identification on a neighborhood/district level and closes with an outlook of necessary next steps to improve the quality of such an approach and increase the potential to use this approach as a strategic instrument.