What is the reasoning for a new network of "DC" transmission lines? Isn't there a much greater loss of power over transmission lines using DC versus AC? That is the reason transmission lines use AC instead of DC in what I have read, is that correct or not?
Is there some new technology that gives DC the advantage over AC in transmission lines now? I would very much like to hear your reasoning for going DC instead of AC. Any reasons for going to DC transmission lines over AC would be highly appreciated, TIA.
There is less loss in DC lines. Since the voltage is constant, and not varying, a line with a given peak voltage can carry more power for the same amperage. Also, since the current is constant, the flow is uniform throughout the conductors, and there is no "skin effect" of higher current and greater heating on the surface of the conductors.
AC was preferred over DC in the past because it was easy to change voltages with transformers. However, there are now solid state convertors to go from AC to DC and back that do the job efficiently.
It is easier to ensure stability between the grids with DC, since you don't have to synchronize phase and frequency between the grids. With AC when you join two grids, you are coupling the mechanical dynamic behaviour of all the big rotating machines of both grids through the electrical interconnection.