Critical mineral demands may limit scaling of green hydrogen production

• Published in: Frontiers in geochemistry 2024-01, Vol.1
• Main Authors: Greenwald, Julia E., Zhao, Mervin, Wicks, Douglas A.
• Format: Article
• Language: English
• ISSN: 2813-5962; 2813-5962
• DOI: 10.3389/fgeoc.2023.1328384

Hydrogen (H 2 ) is widely viewed as critical to the decarbonization of industry and transportation. Water electrolysis powered by renewable electricity, commonly referred to as green H 2 , can be used to generate H 2 with low carbon dioxide emissions. Herein, we analyze the critical mineral and energy demands associated with green H 2 production under three different hypothetical future demand scenarios, ranging from 100–1,000 Mtpa H 2 . For each scenario, we calculate the critical mineral demands required to build water electrolyzers ( i.e. , electrodes and electrolyte) and to build dedicated or additional renewable electricity sources ( i.e. , wind and solar) to power the electrolyzers. Our analysis shows that scaling electrolyzer and renewable energy technologies that use platinum group metals and rare earth elements will likely face supply constraints. Specifically, larger quantities of lanthanum, yttrium, or iridium will be needed to increase electrolyzer capacity and even more neodymium, silicon, zinc, molybdenum, aluminum, and copper will be needed to build dedicated renewable electricity sources. We find that scaling green H 2 production to meet projected net-zero targets will require ∼24,000 TWh of dedicated renewable energy generation, which is roughly the total amount of solar and wind projected to be on the grid in 2050 according to some energy transition models. In summary, critical mineral constraints may hinder the scaling of green H 2 to meet global net-zero emissions targets, motivating the need for the research and development of alternative, low-emission methods of generating H 2 .