Scientists from Massachusetts Institute of Technology have demonstrated a way to produce hydrogen using recycled aluminum cans, seawater and caffeine. The study is published in the journal Cell Reports Physical Science and details how the processed aluminum interacts with seawater salts to produce hydrogen gas. This happens without the formation of a protective oxide film, which normally interferes with the reaction. Adding caffeine, particularly its active component imidazole, speeds up the hydrogen production process by a factor of 5. Based on this, the team created a compact reactor that could be mounted on ships or submersibles. It runs on aluminum pellets from cans and a small amount of gallium with caffeine. A single aluminum pellet can produce 400 ml of hydrogen in 5 minutes. Although the use of gallium and indium must be optimized for scaling, the researchers are also looking at the possibility of obtaining water from the environment, which would further reduce costs. Future plans are to test this technology on a variety of vehicles.