moinsdewatt wrote:...
We don't really need superconducting cables.
High voltage HVDC lines are sufficient.
see here :
http://www.oleocene.org/phpBB3/viewtopi ... 6&start=75There are Nexans and ABB for cables and Alstom for continuous transformer substations and vice versa.
Let's say they have less losses than AC lines, but still more losses than superconductors.
But I agree with you because it is difficult to see how we could cool the thousands of km of high voltage lines to -170 °. Superconducting is only valid for short sections, in urban areas in particular where the disruptive voltage is lower than the voltage which would be necessary for sufficiently low losses, because there is not enough distance between conductors, relative to the insulation.
The advantage of the DC is that there are no losses by radiation or by capacitive or inductive coupling (reactive power). On the other hand, power electronics are needed for the AC / DC and inverse conversion, at each end of the line.
Tesla had rightly won the support for alternating current, against Edison who was favorable to the continuous, because at the time this electronics did not exist. In addition, there were continuous electrolysis problems degrading the connections in rainy weather. Today these two points are better controlled and we can review the choice, at least for transport over long distances. The Russians, since the time of the USSR, given the distances to cover in their country, have been active in this field, setting up such lines, up to almost 1MV.
