Potential vulnerability of US green hydrogen in a world of interdependent networks

Green hydrogen is viewed as a promising pathway to future decarbonized energy systems. However, hydrogen production depends on a few critical minerals, particularly platinum and iridium. Here, we examine how the supply of these minerals is subject to vulnerabilities hidden in interdependent global networks of trade and investment. We develop an index to quantify these vulnerabilities for a combination of a target country, an investing country, an intermediary country and a commodity. Focusing on the US as the target country for the import of platinum and iridium, we show how vulnerability-inducing investing countries changed between 2010 and 2019. We find that the UK is consistently among investing countries that can potentially induce US vulnerabilities via intermediary exporters of platinum and iridium, with South Africa being the primary intermediary country. Future research includes incorporating geopolitical factors and technological innovations to move the index closer from potential to real-world vulnerabilities.