I have no idea how this is applied on other things, but on my submarine, the "bomb" (the oxygen generator, worked by electrolysis...) was the largest non-engineering electrical load on the boat (hundreds of amps IIRC) - the A-gangers would have to call us up before turning it on so we could make sure that the electrical bus would handle the load.
Now, this made plenty of O2 for 150 dudes confined to a 38' diameter tube, but, whenever says "electrolysis" and "makes energy" in the same sentance, it makes me skeptical.
Treadwell Supplies Oxygen Generator Components for Nuclear Subs
wish I could be more specific, but I honestly don't remember and its probably classified...
-ET2/ss