This cutting-edge field promised to accelerate the global transition to clean energy, tackle energy storage challenges, and pave the way for a carbon-free future. Renewable Metal Fuels represented a novel approach to energy storage and transport - metals such as aluminium and iron stored large amounts of renewable energy and released it on demand through reactions with oxygen or water. These reactions produced environmentally friendly and highly recyclable by-products, enabling a sustainable, scalable, and carbon-free energy cycle. Thanks to their high energy density, cost-effectiveness, and minimal environmental impact, these fuels offered a promising alternative to conventional batteries and Power-to-X technologies.