Well, there'[s also the factor that cryogases are rather dangerous to be around let alone directly work with, added on to the expected issues of dealing with high voltage and current. Keeping a significant volume topped up with them would be expensive to operate as well, and depending on how much power it takes to run the support equipment might not even end up any better than conventional copper wires, though I'd want to see some numbers on that before even beginning to assert that such a conclusion is accurate.
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‎noli esse culus
‎noli esse culus