A team of engineers at MIT has developed a groundbreaking method for producing hydrogen gas by combining recycled aluminum soda cans, seawater, and coffee grounds. This innovative approach involves pretreating the aluminum with a rare metal alloy to render it into a pure state. The salt ions in seawater then attract and recover the alloy during the reaction, enabling a sustainable cycle of hydrogen production. Surprisingly, the addition of coffee grounds containing imidazole significantly accelerates the reaction, making it ideal for maritime applications. The researchers are working on a small reactor that can run on marine vessels or underwater vehicles, utilizing aluminum pellets, gallium-indium, and caffeine to generate hydrogen on demand. This sustainable method holds promise for powering engines and fuel cells without emissions, contributing to green energy solutions.