[Jonty30]

What it sounds like to me is that the steam decomposes water and the free oxygen remixes with the iron to become Iron oxide again.

[Navy Patriot]

From the article: "Steam is fed into the reactor to retrieve the stored hydrogen when needed; it can then be converted into electricity or heat easily enough."

I believe the sticking point is that Steam doesn't come free, you have to use energy to make steam unless you have your conversion station in a volcano.