[bkepley]

With the advent of power electronics that can work on the power levels involved now, you will see more and more DC systems going on line, at least to the substation. They have a dramatic drop in line loss due to capacitance and inductance in the system. At the termination point, you have a monster inverter to convert it back to pure sine wave AC current, 3-phase.

This doesn't make a lot of sense to me. Induction and capacitance don't cause any power loss while low voltage DC means in order to deliver power you have to increase current, a lot, which means real power losses in the power lines.

[Aqua225]

Not talking low voltage here. Because DC doesn’t have some of the effects of AC current, you can go much higher on voltage. Think millions. I think some AC systems have gotten that high, but it’s much easier with DC.

And line reactivity *is* a major loss point in the power system. You have a virtual power consumption caused by stray capacitance interacting with the AC signal, which causes a current flow that is out of phase with the voltage, which is unfortunately reflected by extra heat dissipation in transformers, etc., because they are flowing current to feed the reactivity of the line. Heat is loss.

On those big long distribution lines, this is a major problem. The power companies stack capacitors to bring down the reactivity of the distribution lines, but it’s not perfect, it’s only a stop gap actually.