In recent years, circular business models (CBM) have become an inevitable requirement to foster improvements in environmental performance. However, the current literature rarely discusses the link... Show moreIn recent years, circular business models (CBM) have become an inevitable requirement to foster improvements in environmental performance. However, the current literature rarely discusses the link between Internet of Things (IoT) and CBM. This paper first identifies four IoT capabilities including monitoring, tracking, optimization and design evolution for improving CBM performance based on the ReSOLVE framework. In a second step, a systematic literature review using the PRISMA approach analyzes how these capabilities contribute to 6 R and CBM through the CBM-6R and CBM-IoT cross-section heatmaps and relationship frameworks, followed by assessing the quantitative impacts of IoT on potential energy saving in CBM. Finally, challenges are analyzed for the realization of IoT-enabled CBM. The results show that the assessments of Loop and Optimize business models dominate current studies. IoT plays a significant role in these business models respectively through tracking, monitoring and optimization capabilities. While (quantitative) case studies for Virtualize, Exchange and Regenerate CBM are substantially needed. IoT holds the potential to reduce energy consumption by around 20–30% for referenced applications in the literature. However, the IoT hardware, software and protocol energy consumption, interoperability, security and financial investment might become main obstacles for the wider use of IoT in CBM. Show less
Decarbonizing the building stock is critical for realizing the climate-neutral target for the Netherlands. This thesis uses multi-source data, mainly including GIS data of building footprints and... Show moreDecarbonizing the building stock is critical for realizing the climate-neutral target for the Netherlands. This thesis uses multi-source data, mainly including GIS data of building footprints and the archetypes representative of Dutch residential buildings, to develop a series of bottom-up building stock models to track future material stock and flows, energy demand, electricity generation, and GHG emissions. Results demonstrate the great potential for decarbonizing the Dutch residential building sector, while decarbonization strategies should be effectively and extensively implemented. Saving space heating energy consumption is the most direct way to reduce annual GHG emissions. Considering that most existing residential buildings will still be in use in 2050, renovating them with high energy performance standards is required. Despite the great potential of renovation, it alone is not enough to realize the climate-neutral target in the residential building stock because the upstream fossil fuel-based energy systems still emit large amounts of GHG. Replacing fossil fuels with renewable energy sources is a critical path, mainly involving onsite natural gas combustion for space heating and offsite natural gas and coal combustion for electricity and heat (in heat networks) generation. Urban mining cannot contribute to as much GHG emission reduction as energy transition strategies, though, should still be implemented as it can reduce the primary material consumption and CDW landfill. In addition to the technical aspects considered in this thesis, it is also necessary to develop feasible policies in terms of socioeconomic aspects to guarantee the effective and quick deployment of these technical strategies. Show less
Zhang, C.; Hu, M.; Di Maio, F.; Sprecher, B.; Yang, X.; Tukker, A. 2022
The construction sector is the biggest driver of resource consumption and waste generation in Europe. The European Union (EU) is making efforts to move from its traditional linear resource and... Show moreThe construction sector is the biggest driver of resource consumption and waste generation in Europe. The European Union (EU) is making efforts to move from its traditional linear resource and waste management system in the construction sector to a level of high circularity. Based on the theory of circular economy, a new paradigm called waste hierarchy was introduced in the EU Waste Framework Directive. This work uses the framework of the waste hierarchy to analyze the practice of construction and demolition waste (CDW) management in Europe. We explore the evolution of the waste hierarchy in Europe and how it compares with the circular economy. Then, based on the framework, we analyze the performance of CDW management in each EU member state. Innovative treatment methods of CDW, focusing on waste concrete, is investigated. This brings insight into optimizing and upgrading the CDW management in light of advanced technologies and steering the pathway for transitioning the EU towards a circular society. Show less
Material circularity and energy efficiency are highly relevant and intertwined issues for the transition towards a carbon-neutral and circular built environment. In the Netherlands, the building... Show moreMaterial circularity and energy efficiency are highly relevant and intertwined issues for the transition towards a carbon-neutral and circular built environment. In the Netherlands, the building sector has been rendered a priority towards a circular and low-carbon society. This thesis explored potential solutions for these twin issues in light of a novel technological system. This system presents an energy–material efficiency solution for energy renovation of building stocks with prefabricated concrete elements (PCEs) with recycled CDW as feedstock. Life cycle assessment (LCA) and life cycle costing (LCC) were combined with dynamic material flow analysis (MFA) to estimate the economic and environmental implications at both a product level and a national level. 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
Straten, B. van; Heiden, D.R. van der; Robertson, D.; Riekwel, C.; Jansen, F.W.; Elst, M. van der; Horeman, T. 2021
Introduction: Hospitals in the Netherlands generate approximately 1.3 million kg of waste from the polypropylene (PP) wrapping paper (WP) used to wrap surgical instruments each year. The aim of... Show moreIntroduction: Hospitals in the Netherlands generate approximately 1.3 million kg of waste from the polypropylene (PP) wrapping paper (WP) used to wrap surgical instruments each year. The aim of this study was to develop a method to recycle WP waste into new medical devices.Methods: WP was recovered from Maasstad Hospital, Netherlands. The WP was melted into bars, granulated, and mixed with virgin material at different ratios and temperatures. Dog bones were injection-molded from volume (v.%) virgin, mixed (%R), and recycled (100%R) granulate, and a tensile testing machine was used to compare the material properties before and after ten disinfection cycles at the sterilization department. Then, 25 instrument openers were made from the 50%R material and circulated for four weeks.Results: The data indicated no significant differences in the mechanical properties at different melting temperatures. For dog bones made from the 100%R, 50%R, and virgin granulate, the Young's moduli were 1021 (SD13), 879 (SD13), and 795 (SD14) MPa, and the strains were 8%, 12%, and 14%. Ten disinfection cycles did not significantly change the material properties. After one month, the openers did not show any deterioration or damage other than surface scratches.Discussion: The results indicated that the initial WP melting temperature did not influence the mechanical properties. Although devices could be produced directly from the recycled WP granulate, increasing the recycled granulate in the mix ratio increased the strength and brittleness.Conclusions: It is feasible to recycle WP waste into a high-quality raw material for the injection molding of medical devices without using additives. This would allow hospitals to become more compliant with the circular economy enabling economically viable and circular processes that positively contribute to cleaner technical processes, sustainable products, and the reduction of medical waste. Show less
In-use stocks of products can be considered as intermediaries between human needs and the physical world. During use, they fulfil important functions, but they can also be seen as a source of... Show moreIn-use stocks of products can be considered as intermediaries between human needs and the physical world. During use, they fulfil important functions, but they can also be seen as a source of materials for the future: the production of secondary materials. This idea of an urban mine is applied to copper in China in this dissertation. Taking into account that most modern technologies rely on copper, consumption of diverse copper-containing products in China is increasing rapidly. The in-use copper stocks have become a large reservoir for urban mining. It is of crucial importance to secure future supply by closing copper cycles, thereby also reducing environmental pressure. Therefore, the aim of this research is to explore how the stocks and flows related to the Chinese copper cycle can be transformed into a sustainable and circular economy. The material flow analysis and life cycle assessment approaches are used to quantify the in-use stocks, demand and waste generation for copper under the Chinese policies related to general economic development, the energy transition and ambitions with regard to circular economy, and assess associated environmental impacts as well as identify potential options to realize the dematerialization and environmental sustainability of the copper cycle in China. Show less
A sustainable resource management is an essential aspect to satisfy the current human needs without compromising the needs of future generations. There is a need to provide resource-efficient... Show moreA sustainable resource management is an essential aspect to satisfy the current human needs without compromising the needs of future generations. There is a need to provide resource-efficient strategies that enables to decrease the risk of disruptive supply chains while maintaining natural resources for the current and future generations. Within this context, circular economy has been proposed as a paradigm that aims to reduce resource extraction and waste flows by retaining materials into the economy. However, there is still a lack of understanding on how a global circularity transition might look like, and what would be the magnitude of the potential economic, social, and environmental implications of material circularity on macro scale. These aspects raise the questions: Is circular economy a sustainable solution to achieve a global economic and environmental sustainability? And what are the macroeconomic, social, and environmental implications of a transition to a circular economy? A macro level assessment of material circularity aims to understand how material circularity could contribute to sustainable resource management, and explore which circularity interventions could support a cost-effective circularity transition on a macro scale. 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