João Patrício

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%.