ZPM factory

I am looking for a story where Rodney finds a factory that either makes or charges ZPMs. It is located on a moon or some sort of satellite where here are wires leading between the moon and its planet(?) similar to a space elevator that work to charge the ZPMs. Rodney shows Sheppard the factory without anyone else there and they decide not to tell any(specifically the sgc) about it.

Thank you.