I don't really understand why iron is being considered over aluminum. Is aluminum production from ore too complex compared to iron? I would have to imagine burning metallic aluminum produces much more energy per gram.
It’s just a ridiculously expensive metal to make.
Look up how much alumina is minded all over the world, how it’s shipped to Iceland for processing because of their cheap geothermal electricity, then shipped to China to processing, then shipped back around the world to final destination. It’s crazy.