Yosuke Shigetomi

Global flows of critical metals necessary for low-carbon technologies: The case of neodymium, cobalt, and platinum

This study, encompassing 231 countries and regions, quantifies the global transfer of three critical metals (neodymium, cobalt, and platinum) considered vital for low-carbon technologies by means of material flow analysis (MFA), using trade data (BACI) and the metal contents of trade commodities, resolving the optimization problem to ensure the material balance of the metals within each country and region. The study shows that in 2005 international trade led to global flows of 18.6 kt of neodymium, 154 kt of cobalt, and 402 t of platinum and identifies the main commodities and top 50 bilateral trade links embodying these metals. To explore the issue of consumption efficiency, the flows were characterized according to the technological level of each country or region and divided into three types: green (“efficient use”), yellow (“moderately efficient use”), and red (“inefficient use”). On this basis, the shares of green, yellow, and red flows in the aggregate global flow of Nd were found to be 1.2%, 98%, and 1.2%, respectively. For Co, the respective figures are 53%, 28%, and 19%, and for Pt 15%, 84%, and 0.87%. Furthermore, a simple indicator focusing on the composition of the three colored flows for each commodity was developed to identify trade commodities that should be prioritized for urgent technical improvement to reduce wasteful use of the metals. Based on the indicator, we discuss logical, strategic identification of the responsibilities and roles of the countries involved in the global flows.

Global Mining Risk Footprint of Critical Metals Necessary for Low- Carbon Technologies: The Case of Neodymium, Cobalt, and Platinum in Japan

Meeting the 2-degree global warming target requires wide adoption of low-carbon energy technologies. Many such technologies rely on the use of precious metals, however, increasing the dependence of national economies on these resources. Among such metals, those with supply security concerns are referred to as critical metals. Using the Policy Potential Index developed by the Fraser Institute, this study developed a new footprint indicator, the mining risk footprint (MRF), to quantify the mining risk directly and indirectly affecting a national economy through its consumption of critical metals. We formulated the MRF as a product of the material footprint (MF) of the consuming country and the mining risks of the countries where the materials are mined. A case study was conducted for the 2005 Japanese economy to determine the MF and MRF for three critical metals essential for emerging energy technologies: neodymium, cobalt and platinum. The results indicate that in 2005 the MFs generated by Japanese domestic final demand, that is, the consumption-based metal output of Japan, were 1.0 × 10(3) t for neodymium, 9.4 × 10(3) t for cobalt, and 2.1 × 10 t for platinum. Export demand contributes most to the MF, accounting for 3.0 × 10(3) t, 1.3 × 10(5) t, and 3.1 × 10 t, respectively. The MRFs of Japanese total final demand (domestic plus export) were calculated to be 1.7 × 10 points for neodymium, 4.5 × 10(-2) points for cobalt, and 5.6 points for platinum, implying that the Japanese economy is incurring a high mining risk through its use of neodymium. This countrys MRFs are all dominated by export demand. The paper concludes by discussing the policy implications and future research directions for measuring the MFs and MRFs of critical metals. For countries poorly endowed with mineral resources, adopting low-carbon energy technologies may imply a shifting of risk from carbon resources to other natural resources, in particular critical metals, and a trade-off between increased mining risk and deployment of such technologies. Our analysis constitutes a first step toward quantifying and managing the risks associated with natural resource mining.

Changes in the Carbon Footprint of Japanese Households in an Aging Society

As the aging and low birthrate trends continue in Japan, and as changes in the working population and consumption patterns occur, new factors are expected to have an impact on consumption-based greenhouse gas (GHG) emissions. We present the impacts of changes in the composition of Japanese households on GHG emission structures using current (2005) consumption-based accounting on the commodity sectors that are expected to require priority efforts for reducing emissions in 2035. This is done using the Global Link Input-Output model (GLIO) and domestic household consumption data and assuming that recent detailed consumption expenditures based on the Social Accounting Matrix (SAM) will continue into the future. The results show that consumption-based GHG emissions derived from Japanese household consumption in 2035 are estimated to be 1061 Mt-CO2eq (4.2% lower than in 2005). This study can be used to reveal more information and as a resource in developing policies to more meticulously and efficiently reduce emissions based on emission and import rates for each domestic and overseas commodity supply chain.

The role of primary processing in the supply risks of critical metals

ABSTRACT This study seeks to understand the role of primary processing, i.e. the first post-mining stage, in supply risk, by means of a case study on three critical metals (neodymium, cobalt, and platinum) in the context of Japan. Applying the ‘footprint’ concept with a multiregional input–output model, we have quantified the direct and indirect vulnerability of the Japanese economy to such risks. Considering the supply risks associated with primary processors, we find that Japanese final consumers are exposed to relatively higher supply risks for neodymium as compared with cobalt and platinum. Our study shows that the primary processing stage of a metal’s supply chain may contribute significantly to the overall supply risks, suggesting that this stage should be taken into due account in understanding and mitigating supply-chain vulnerability through, e.g. supplier diversification and alternative material development.

Visualizing the shape of society: An analysis of public bads and burden allocation due to household consumption using an input-output approach

This study investigates how our lifestyles can cause societal issue including a reduction in social equity due to the consumption of natural resources. Based on a range of household environmental footprints and their application to a quantitative social equity evaluation framework, a methodology is proposed which identifies the creation and origin of public bads within society. This research builds on the methodologies of energy policy sustainability evaluation incorporated with environmentally extended input output analysis in order to critically assess lifestyle-based consumption impacts, and to quantify the allocation of subsequent burdens across generations. Further, the proposed methodology is applied to a case study in Japan, an aging, shrinking population. Analysis identifies the increasing burden originating with elderly generations, and due to the resolution offered by the methodology, specifically identifies commodities and services which underpin these future burdens, allowing for policy implications to be drawn. The public bads and consumption burden indicator established through the described methodology is proposed as a footprint harmonizing tool to assess sustainability and supplement the footprint family.