If your saving efficiency in current transfer how much are you using to produce and pump the liquid nitrogen ...

Hmmmm the capital cost // efficiency // overheads - running a comparative amount of power over say 1000Km.
Some numbers up front please?

Why do you need wires to transmit commercial electricity when you could simply deliver a massive capacitor full every few seconds via a vectored arc (sorry Mr. Tesla, you were close). Repeaters when and where necessary.

Well- it\'s a nice idea, theoretically. But you aren\'t going to change infrastructures with any wires that must be cooled by any gases- cost would be astronomical.
No mention if the electrons act the same way they do in a real copper wire (ie: is current still conveyed for motors/electromagnetic use?), or is simply for transporting electrical energy from one spot to another?

Drakesword: since several wires can be cooled at once, the cooling/volt could be pretty favorable. Of course, the huge problem with these lines is their performance in disasters: that much power would likely cause explosions if the line broke.

Given that superconductors do not produce heat when current is passing through them, and insulation is cheap, the cost of generating the cryogenic nitrogen is significantly less than than the cost of the line loss of even copper transmission lines.

hello. are you growing these sapphire crystals? is that what makes this attractive over the abundance of copper? in what way does this compare to encasing copper in ceramic and liquid nitrogen? perhaps such tremendous wastes of time and money will lead to the next step.

Re; rollzone
To get copper to superconduct you have to cool far beyond liquid nitrogen. The colder you go the more it costs. Additionally there is a limit to how much energy can be carries by a superconductor before it stops superconducting even when supercooled the sapphire might be better.

Hmmm.... sapphire, ultrastrong, relatively cheap. Liquid nitrogen ? solar driven stirling low vacuum refrigeration compressor/ evaporators systems in a line drop xfmr - xfmr system? The cooling\'s more esoteric than the sapphire Sconductors. It would be sensible to use this tech for substation transformers, but again...Liquid Nitrogen!

I had thought that high-temperature superconductors that only needed liquid N2 cooling were still very exotic and not ready for industrial use. Only having to go as low as liquid N2 is, according to my understanding, a big breakthrough. Previously it was all about liquid helium, I think, which really is way too cold to be practical.
Don\'t forget that the air is about 70% nitrogen, so the stuff is everywhere, just waiting to be separated, cooled down and used. I\'m guessing the money to be saved by even a small decrease in ohmic losses on a power line would more than pay for the energy, equipment and maintenance needed to liquify the nitrogen to do the cooling.