Managing Critical Materials with a Technology-Specific Stocks and Flows Model

Abstract

The transition to low carbon infrastructure systems required to meet climate change mitigation targets will involve an unprecedented roll-out of technologies reliant upon materials not previously widespread in infrastructure. Many of these materials (including lithium and rare earth metals) are at risk of supply disruption. To ensure the future sustainability and resilience of infrastructure, circular economy policies must be crafted to manage these critical materials effectively. These policies can only be effective if supported by an understanding of the material demands of infrastructure transition and what reuse and recycling options are possible given the future availability of end-of-life stocks. This Article presents a novel, enhanced stocks and flows model for the dynamic assessment of material demands resulting from infrastructure transitions. By including a hierarchical, nested description of infrastructure technologies, their components, and the materials they contain, this model can be used to quantify the effectiveness of recovery at both a technology remanufacturing and reuse level and a material recycling level. The model’s potential is demonstrated on a case study on the roll-out of electric vehicles in the UK forecast by UK Department of Energy and Climate Change scenarios. The results suggest policy action should be taken to ensure Li-ion battery recycling infrastructure is in place by 2025 and NdFeB motor magnets should be designed for reuse. This could result in a reduction in primary demand for lithium of 40% and neodymium of 70%.

Implications of Emerging Vehicle Technologies on Rare Earth Supply and Demand in the United States

“…Our flow and stock scenarios join a growing literature of studies with long time horizons of vehicles and the materials in them [18,19,21,22,26,27]. The if-then scenario approach inherently includes assumptions and simplifications that omit various factors.…”

“…However, the growing stock of vehicles can serve as an eventual supplier of materials when the vehicles reach the end of their useful life. Research into current and future vehicle fleets and their implications on various materials has been conducted on the global scale and in the UK, Japan, and European countries [18][19][20], and some studies focused specifically on critical materials in vehicles [21][22][23][24][25][26][27]. However, to date these issues have not been explored the context of the US, currently the second largest vehicle market in the world.…”

The future in and of criticality assessments

“…The aftermath of these policies affects manufacturers and companies, which have to adapt their supply chain and account for the shrinking stock in mineral resources leading to a change in their supply (Bradshaw & Hamacher, ; Habib & Wenzel, ). For example, the trend toward a decarbonized energy sector with the use of technologies such as wind turbines and electric vehicles has increased exponentially the demand for metals that are considered “critical” and can present supply‐related risks in the coming years (Alonso et al., ; Bradshaw, Reuter, & Hamacher, ; Busch, Steinberger, Dawson, Purnell, & Roelich, ; Candelise, Speirs, & Gross, ; Houari, Speirs, Candelise, & Gross, ). At the same time, considerable amounts of material stocks have accumulated in developed societies and are available as secondary resources (Haas, Krausmann, Wiedenhofer, & Heinz, ; Tanikawa, Fishman, Okuoka, & Sugimoto, ).…”

Deriving European Tantalum Flows Using Trade and Production Statistics

“…Though there have been numerous studies describing the flows of critical materials (Busch et al 2014; BIO by Delloite 2015; Guyonnet et al 2015), existing literature on the supply chain of tantalum is limited. Previous studies discussing the use of tantalum in various products have been able to describe the tantalum supply chain at a high level of detail, but only in a qualitative sense (Jeangrand 2005;Espinoza 2012;EU 2014).…”