I'm curious, neglecting all the worries about temperature, etc (assume those conditions can be met)... Is there a limit to the amount of energy that can be stored in a superconductor? Is there a formula to calculate it? What causes this limit, etc? Is there a massive field generated by the current? Is there a theoretical maximum for a magnetic field generated by the current? Is there a theoretical maximum "saturation" limit where no more electrons can be packed onto the surface or within the structure (do they only reside on the surface in a superconductor? am I way off my rocker on this part? I dunno...) Is the amount of energy stored based on the eV of each electron? I'm really clueless on this as you can tell, I'm trying to figure it out, and the insanely formula-heavy papers I've tried to read haven't helped a whole lot to get the basics. Basically, I'm assuming a ring shaped superconductor, just to throw out some numbers, let's say it's 5cm diameter, and the "wire" is 1mm thick. Is this limited to a certain number? What if we doubled the diameter and kept the same thickness of the "wire"? What if we made the "wire" 1cm thick instead of 1mm, and kept the same diameter of the ring?