[Amps] Benefits of 3-phase power?

[R.Measures]

>I too was very surprised to find HV single phase power
>distribution when I arrived here from England. I had
>always understood that long(ish) transmission lines
>needed to be 3 phase 

California imports hydro-power from the North with a 1,000,000VDC, 
center-tap grounded transmission line.  In Sylmar, there's a rather 
largish DC to AC inverter.
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