Headline theatrics aside, this seems like a neat idea. However, the article doesn’t mention how this compares to systems that use electrolysis to generate hydrogen. In general the number of mechanical moving parts required for this system, and the idea of rusting and de-rusting these metals over and over doesn’t seem feasible compared to simply using electricity to separate the hydrogen. A quick google says electrolysis is around 70-80% efficient, I don’t see this setup ever beating that.