Proton exchange membrane (PEM) water electrolyzers are a promising technology for high-purity, efficient green hydrogen production, with expanding installations. This has increased demand for... Show moreProton exchange membrane (PEM) water electrolyzers are a promising technology for high-purity, efficient green hydrogen production, with expanding installations. This has increased demand for materials like platinum (Pt) used in PEM manufacturing. Conversely, Pt, which currently serves primarily as catalysts for internal combustion engine vehicles (ICEVs), would become available as ICEVs are phased out. Here, we simulate the Pt requirements for rapid scale-up PEM electrolyzers and quantitatively compare these requirements with the availability of Pt from scraped autocatalysts under the IEA-NZE scenario. Our results show that demand for Pt in PEM electrolyzers is expected to increase by an order of magnitude by 2050, while ICEVs are expected to cumulatively scrap ∼2500 tons of Pt. The Pt surplus from ICEVs would meet the increasing Pt demand for PEM eletrolyzers from 2030 onwards. These findings offer fresh insights into using the potential of urban mines to meet the energy transition challenges. Show less
Gervais, E.; Kleijn, E.G.M.; Nold, S.; Voet, E. van der 2023
Supply concentration and environmental, social, governance (ESG) issues constitute important supply risks. With strategic autonomy and responsible sourcing high on the political agenda these risks... Show moreSupply concentration and environmental, social, governance (ESG) issues constitute important supply risks. With strategic autonomy and responsible sourcing high on the political agenda these risks are especially relevant for the EU. This paper proposes an approach to conduct risk-based due diligence. Using a trade-linked material flow analysis, ESG and dependency hotspots along supply chains can be identified. Silver supply chains for photovoltaics (PV) are taken as case-study. The model traces silver from mining to PV module manufacturing, from 1995 to 2021. The supply of silver powder, paste, PV cells, and modules is found to be highly concentrated. These supply chains are linked to substantial ESG risks, mostly nested in fabrication and manufacturing, some of which have worsened over time. Over 87% of the silver used in PV transits through at least one country with a very high risk factor. Reshoring the PV industry to the EU can partially de-risk supply. Show less
Oorschot, J. van; Sprecher, B.; Rijken, B.; Witteveen, P.; Blok, M.; Schouten, N.; Voet, E. van der 2023
Buildings are an important part of society's environmental impacts, both in the construction and in the use phase. As the energy performance of buildings improve, construction materials become more... Show moreBuildings are an important part of society's environmental impacts, both in the construction and in the use phase. As the energy performance of buildings improve, construction materials become more important as a cause of environmental impact. Less attention has been given to those materials. We explore, as an alternative for conventional buildings, the use of biobased materials and circular building practices. In addition to building design, we analyze the effect of urbanization. We assess the potential to close material cycles together with the material related impact, between 2018 and 2050 in the Netherlands. Our results show a limited potential to close material cycles until 2050, as a result of slow stock turnover and growth of the building stock. At present, end-of-life recycling rates are low, further limiting circularity. Primary material demand can be lowered when shifting toward biobased or circular construction. This shift also reduces material related carbon emissions. Large-scale implementation of biobased construction, however, drastically increases land area required for wood production. Material demand differs strongly spatially and depends on the degree of urbanization. Urbanization results in higher building replacement rates, but constructed dwellings are generally small compared to scenarios with more rural developments. The approach presented in this work can be used to analyze strategies aimed at closing material cycles in the building sector and lowering buildings' embodied environmental impact, at different spatial scales. Show less
Deployment of clean energy technologies will require a considerable amount of materials. The surge in demand for metals related to emerging energy technologies may hinder the energy transition. In... Show moreDeployment of clean energy technologies will require a considerable amount of materials. The surge in demand for metals related to emerging energy technologies may hinder the energy transition. In this study we provide a comprehensive overview and analysis of existing work in this field, a solid quantitative baseline for material requirements of different energy technologies and quantitative information that can be used to generate learning curves for the material requirements of different energy technologies. We conducted a quantitative review of the material requirements of low-carbon energy technologies in 132 scientific publications, and provided a comparative analysis of detailed data including material intensity and lifetime data. Besides providing a large amount of structured quantitative data, the results of our work indicate that: (1) research on the demand for low carbon technology related metals has received much attention since the 2010s; (2) around 80% of the publications focus on the global level while national level studies are underrepresented; (3) science-based future scenarios are the main means of estimating total future material requirements; (4) most studies foresee material constraints of large-scale implementation of low-carbon technologies and the secure and responsible supply of these materials is still the subject of discussion; (5) changes in metal intensity caused by technological development and material requirements for non-critical components are important though often overlooked. Show less
Verhagen, T.J.; Cetinay, H.; Voet, E. van der; Sprecher, B. 2022
To achieve climate neutrality, future urban heating systems will need to use a variety of low-carbon heating technologies. The transition toward low-carbon heating technologies necessitates a... Show moreTo achieve climate neutrality, future urban heating systems will need to use a variety of low-carbon heating technologies. The transition toward low-carbon heating technologies necessitates a complete restructuring of the heating system, with significant associated material requirements. However, little research has been done into the quantity and environmental impact of the required materials for this system change. We analyzed the material demand and the environmental impact of the transition toward low-carbon heating in the Netherlands across three scenarios based on the local availability and capacity for sources of low-carbon heat. A wide range of materials are included, covering aggregates, construction materials, metals, plastics, and critical materials. We find that while the Dutch policy goal of reducing GHG emissions by 90% before 2050 can be achieved if only direct emissions from the heating system are considered, this is no longer the case when the cradle-to-gate emissions from the additional materials, especially insulation materials, are taken into account. The implementation of these technologies will require 59–63 megatons of materials in the period of 2021–2050, leading to a maximum reduction of 62%. Show less
Inaugural Lecture by Prof.Dr. Ester van der Voet on the acceptance of her position as Associate Professor at the chair of Sustainable Resource Use at Leiden University on Monday 2 Mei 2022
Dong, D.; Tukker, A.; Steubing, B.R.P.; Oers, L.F.C.M. van; Rechberger, H.; Aguilar Hernandez, G.A.; ... ; Voet, E. van der 2022
To conserve resources and enhance the environmental performance, China has launched the "Zero waste" concept, focused on reutilization of solid waste and recovery of materials, including copper.... Show moreTo conserve resources and enhance the environmental performance, China has launched the "Zero waste" concept, focused on reutilization of solid waste and recovery of materials, including copper. Although several studies have assessed the copper demand and recycling, there is a lack of understanding on how different waste management options would potentially reduce primary copper demand and associated environmental impacts in China in the context of energy transition. This study addresses this gap in view of a transition to low-carbon energy system and the optimization of copper waste management combining MFA and LCA approaches. Six types of waste streams (C&DW, ELV, WEEE, IEW, MSW, ICW) are investigated in relation to various "Zero waste" strategies including reduction, reuse (repair, remanufacturing or refurbishment), recycling and transition from informal to formal waste management. Under present Chinese policies, reuse and recycling of copper containing products will lead to a somewhat lower dependency on primary copper in 2100 (11187Gg), as well as lower total GHG emissions (64869 Gg CO2-eq.) and cumulative energy demand (1.18x10 boolean AND 12 MJ). Maximizing such "Zero waste" options may lead to a further reduction, resulting in 65% potential reduction of primary copper demand, around 55% potential reduction of total GHG emissions and total cumulative energy demand in 2100. Several policy actions are proposed to provide insights into future waste management in China as well as some of the challenges involved. Show less
Oorschot, J. van; Voet, E. van der; Blok, M.; Schouten, N.; Witteveen, P.; Rijken, B.; Hoorn, A. van 2022
Raw Materials are crucial in the development, production, and improvement of modern-day technology. Reliable access to critical, scarce, and valuable materials used in electronics is becoming a... Show moreRaw Materials are crucial in the development, production, and improvement of modern-day technology. Reliable access to critical, scarce, and valuable materials used in electronics is becoming a worldwide concern. Therefore, the quantification of material recovery from the urban mine is currently pursued worldwide. Commonly, data on (Waste) Electrical and Electronic Equipment is scattered, not harmo-nized, and uses different types of classifications and terminology. This provides a big challenge of a structured mapping of secondary raw materials in the urban mine. To address these issues, a state-of -the-art methodology has been developed and is presented by analyzing and tracking printed circuit boards in different key Electrical and Electronic Equipment over time. A total of 4051 composition data records where analyzed to extract the concentration of 19 elements in printed circuit boards between 1990 until 2020. The methodology harmonizes urban mine data, provides structured information that can be used to analyze and monitor the impact of product trends on their components and concentration of the elements in electronics. The resulting database and harmonization protocols are made freely available at the urban mine platform. (c) 2021 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Show less
Deetman, S.P.; Boer, H.S. de; Engelenburg, M. van; Voet, E. van der; Vuuren, D.P. van 2021
We analyse how the global material stocks and flows related to the electricity sector may develop towards 2050. We focus on three electricity sub-systems, being generation, transmission and storage... Show moreWe analyse how the global material stocks and flows related to the electricity sector may develop towards 2050. We focus on three electricity sub-systems, being generation, transmission and storage and present a model covering both bulk and critical materials such as steel, aluminium and neodymium. Results are based on the second Shared Socio-Economic Pathway scenario, with additional climate policy assumptions based on the IMAGE integrated assessment framework, in combination with dynamic stock modelling and an elaborate review of material intensities.Results show a rapid growth in the demand for most materials in the electricity sector, as a consequence of increased electricity demand and a shift towards renewable electricity technologies, which have higher material intensities and drive the expansion of transmission infrastructure and electricity storage capacity. Under climate policy assumptions, the annual demand for most materials is expected to grow further towards 2050. For neodymium, the annual demand grows by a factor 4.4. Global demand for steel and aluminium in the electricity sector grows by a factor 2 in the baseline or 2.6 in the 2-degree climate policy scenario.We show that the combination of rapid growth of capital stocks and long lifetimes of technologies leads to a mismatch between annual demand and the availability of secondary materials within the electricity sector. This may limit the sector to accomplish circular material flows, especially under climate policy assumptions. We also highlight the potential for electric vehicles to curb some of the material demand related to electricity storage through adoption of vehicle-to-grid services. Show less
Koning, A. de; Oorschot, J. van; Voet, E. van der 2021
Copper demand in China is expected to grow considerably over the coming decades, driving energy use and environmental impacts related to copper production. To explore the environmental impacts of... Show moreCopper demand in China is expected to grow considerably over the coming decades, driving energy use and environmental impacts related to copper production. To explore the environmental impacts of copper production in China, we used a variant of Life Cycle Sustainability Analysis that combined the Life Cycle Assessment methodology with the Chinese copper demand projections from 2010 to 2050. The results indicate that the environmental impacts of pyrometallurgical copper production are expected to increase more than twofold during this period and remain the largest contributor to the environmental footprint. Secondary copper production emits the least pollutions. Increasing the share of secondary copper production is the most environmental friendly option for copper production. To this end, China may focus on improving the classification of waste copper products and recycling infrastructure for end-of-life management. Hard coal use and production are crucial contributors to climate change in the context of copper production. Cleaning up copper production processes and improving energy efficiency would also help reduce environmental impacts. Energy transition can significantly reduce the environmental impacts of copper production, but it also can increase copper requirement.It does not visibly contribute to reduce human toxicity as well. (C) 2020 The Author(s). Published by Elsevier Ltd. Show less
Dong, D.; Espinoza, L.A.T.; Loibl, A.; Pfaff, M.; Tukker, A.; Voet, E. van der 2020
Copper is widely used in buildings, transportation and home appliances, resulting in steadily increasing demand in China. From 2013 on, China has implemented the "Green Fence" policy to restrict... Show moreCopper is widely used in buildings, transportation and home appliances, resulting in steadily increasing demand in China. From 2013 on, China has implemented the "Green Fence" policy to restrict copper scrap imports, which have affected and will continue to affect its future copper supply. To explore how China's copper demand can be met in the future, including the effects of the "Green Fence" policy change, in this paper a stock-driven approach is combined with a scenario analysis. We compare two scenarios (Continuity Policy, Circular Economy) and assess the influence of the "Green Fence" policy on each. We conclude that effective measures to prolong product lifetime could lead to a significant reduction in copper demand. Given the limited scope for domestic mining, China will still have to depend largely on imports of primary material in the form of concentrates and refined copper or, otherwise, put major emphasis on its recycling industry and continue to import high-quality copper scrap. In combination with the establishment of a state-of-the-art, efficient and environmentally friendly recycling industry, secondary copper could satisfy the bulk of Chinese copper demand and this could be an opportunity for China to transition to a more circular economy with regard to copper. Show less
