Clean Energy Transition, Scarcity and Urban Mining

The low-carbon economy is a materials economy. Clean energy technologies – essential for the reduction of carbon emissions – require large amounts of critical materials such as cobalt and lithium for energy storage, rare earth minerals for wind turbines, and silver and silicon for solar panels. The supply of these critical materials cannot keep up with skyrocketing demand, which may slow or hinder the transition to clean energy. In this paper the authors present two practical approaches aimed at preserving the clean energy transition momentum: (i) Material Reduction, i.e., changes to production technology to reduce the critical materials used; (ii) Urban Mining, i.e., recovering and recycling critical materials from end-of-life clean energy technology products. The authors show that the effectiveness of these two approaches depends on the levels of material scarcity and systemic leakage in circular infrastructures, as well as policy objectives. Their results further suggest that urban mining is the only means to improve the economic viability of producing clean energy technology. In contrast, when material scarcity is high (low), a long-term focus on clean energy production favors Urban Mining (Material Reduction). Furthermore, systemic leakage in circularity infrastructures moderates this choice and there is an optimal level of circularity in the design of Urban Mining systems that maximizes clean energy generation in the long run.