Metals have an important role in the global economy. With the energy transition, the demand for many metals is expected to sharply increase in the future. Although many studies apply prospective... Show moreMetals have an important role in the global economy. With the energy transition, the demand for many metals is expected to sharply increase in the future. Although many studies apply prospective LCA to assess future environmental impacts of metal supply, the methods have not yet converged to a common approach. This study aims to provide an overview of these studies and their approaches, following 2 research questions: 1. Which metals have been addressed by previous prospective LCA studies and what are their expected future supply impacts according to the identified studies? 2. What are the studied parameters of the metal supply chains, the applied scenario modelling approaches, and data sources used? We performed a systematic literature review to identify studies which assess future environmental impacts due to the supply of metals. This includes publications about absolute impacts of global metal demand, but also relative impacts assessed by comparative LCAs of emerging technologies. For these studies, we analysed both the results and the methods to integrate prospective elements in the LCA models focussing on the choice of parameters, background scenarios, data sources and modelling approaches. The literature review yielded 40 papers. We found that the majority of publications investigate bulk metals like Cu, Fe and Al. Most studies investigate relative impacts (i.e. per kg metal produced). Fewer studies also address absolute impacts of the total future demand; however, these mostly agree that absolute environmental impacts associated with global metal demand are likely to increase. Moreover, the results show that the majority of studies assess CO2 emissions, while other impacts are less often investigated. Furthermore, we found that the parameters considered most frequently are future ore grades, recycling shares, and energy efficiency. Background scenarios were primarily energy scenarios, which were most often electricity scenarios from the integrated assessment model IMAGE. Background scenarios modelling other developments are less common. Overall, the review reveals a wide variety of parameter choices, scenario modelling approaches and data sources. This study stresses the necessity to reduce environmental impacts of metal supply. Moreover, it highlights the need for guidelines for prospective LCA as well as for the documentation of modelling choices, LCI and scenario data to facilitate transparency and sharing of LCA scenarios in the community. Show less
The role of material production as a driver of environmental impacts is increasing, which calls for a better understanding of global material flows. This thesis explores the role of in-use stocks... Show moreThe role of material production as a driver of environmental impacts is increasing, which calls for a better understanding of global material flows. This thesis explores the role of in-use stocks of products, buildings and infrastructure as a key driver of global material demand and discusses the implications with regards to availability of waste flows. The method based on detailed product compositions and lifetimes is applied to generate material use scenario’s towards 2050 for appliances, vehicles, buildings and electricity infrastructure. Under most of the developed scenarios, a growing population and increasing affluence are expected to lead to higher demand for products, and consequentially leads to a continued growth in annual material demand worldwide. While the results can be used to identify sector specific challenges and opportunities for achieving a more circular economy, the method also provides a starting point to incorporate material cycles and resource efficiency strategies more explicitly and consistently in integrated assessment models. This would allow for a more comprehensive assessment of resource use in relation to other global challenges such as climate change. Show less
Donati, F.; Aguilar Hernandez, G.A.; Sigüenza-Sánchez, C.P.; Koning, A. de; Dias Rodrigues, J.F.; Tukker, A. 2019
A circular economy is an industrial system that is restorative or regenerative by intention or design. During the last decade, the circular economy became an attractive paradigm to increase global... Show moreA circular economy is an industrial system that is restorative or regenerative by intention or design. During the last decade, the circular economy became an attractive paradigm to increase global welfare while minimizing the environmental impacts of economic activities. Although several studies concerning the potential benefits and drawbacks of policies that implement the new paradigm have been performed, there is currently no standardized theoretical model or software to execute such assessment. In order to fill this gap, in the present paper we show how to perform these analyses using Environmentally Extended Input-Output Analysis. We also describe a python package (pycirk) for modeling Circular Economy scenarios in the context of the Environmentally Extended Multi-Regional Input-Output database EXIOBASE V3.3, for the year 2011. We exemplify the methods and software through a what-if zero-cost case study on two circular economy strategies (Resource Efficiency and Product Lifetime Extension), four environmental pressures and two socio-economic factors. Show less
To limit the effects of climate change, global average temperature since pre-industrial measurements are to be kept well below 2 °C preferably even at 1.5 °C. The 2 °C limit and certainly the... Show moreTo limit the effects of climate change, global average temperature since pre-industrial measurements are to be kept well below 2 °C preferably even at 1.5 °C. The 2 °C limit and certainly the 1.5 °C target means that substantial GHG emission reductions should be realized already by 2050. How these emission reductions should be achieved is unclear. At least it is clear that the use of fossil fuels should be reduced. It is important to know if indeed the introduction of the renewable energy technologies can achieve the deep GHG emission reduction that are required in 30 years’ time against a backdrop of population growth and economic growth. Therefore we investigated the effects of the introduction of renewable technologies on GHG emissions and resource use until 2050. The principal global economy-environment model used in this investigation is based on a global multi-regional environmentally extended input-output framework which might be called a structural economic model. Because long-term socio-economic and technological developments cannot be predicted several scenarios with different penetration rates of low carbon and renewable energy technologies and resulting GHG emissions and resource use have been implemented in the structural economic model. Show less
SMALL Savannah is an Environmental Information System designed for the integrated analysis and sustainable land management in the savannas region of the Far North of Cameroon. This system combines... Show moreSMALL Savannah is an Environmental Information System designed for the integrated analysis and sustainable land management in the savannas region of the Far North of Cameroon. This system combines an observation and spatial analysis module for the representation of phenomena from various geographic data sources, with a module for the explanation and prediction of land use pattern and changes, and a dynamic modelling and simulation module for the exploration of possible land use change trajectories. Due to a high demographic pressure combined with an increasing human mobility, many changes have occurred in the land use of the study area during the last two decades. These dynamics have led to land saturation resulting in more competition between land uses and conflicts between actors. The spatial and quantitative analysis for the observation period (1987-1999) indicates that accessibility to the main urban centre, soil suitability and population pressure, have been the main driving factors behind this process. According to assumption formulated for future development, it is expected that changes in land use of this area will continue to depend on these factors. But, the land use trajectories will be mainly influenced by the implication of urban actors and the potential investment of local actors for improving land quality and management. The simulations performed for the period 1999 to 2010 indicate areas where changes are likely to occur, thus providing a possibility to evaluate the spatial impact of a given land management policy. The information system under development is an appropriate tool for a regional monitoring system of land use change and rural development. It can be used by scientist and actors involved in land use planning for decision making and adaptive land use management. Another utilisation can be considered with local actors in order to discuss and prepare any concertation or negotiation when dealing with participatory approach of land use and management. Show less