A Methodological Proposal for the Metals' Supply Chain Risk Analysis of Investments Applied to Solar Energy Technologies in Europe

This paper focuses on assessing the potential risks and strengths along the supply chain of a set of ten popular and precious metals associated with two solar energy technologies: concentrated solar power with thermal storage and photovoltaics with batteries. The Extended Multi-Regional Input-Output methodology is used to quantify the required extraction of the metals along the value chain. First, various metrics and indicators are explored to analyze the supply chain. Second, a framework of analysis is proposed to cover the main components of supply chain risks and strengths. Then, we compare the results from two perspectives: analysis of individual supply risk components and a combined index representing the strength of the value chain. The results show, in general, a better performance of the concentrated solar power supply chain in terms of resource availability and supplier diversity, but slightly worse scores in the resilience and governance components. The index reflects better overall performance for concentrated solar power. Among metals, platinum, silver, and tin play the leading role in the analyzed risks. The European deployment of renewables should be accompanied by measures to secure supply, such as cooperation agreements, and also foster the recovery of secondary materials, thereby maximizing intra-European resilience.