Re: primary solid/tube

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 7/12/02 8:34:30 PM Eastern Daylight Time, tesla-at-pupman-dot-com
writes:


>
> I was fascinated to find out that DC!! Is used in long distance power 
> transmission! Wow I thought one could not transmit DC more than a few miles. 
> And that this why we all use Tesla’s AC and not Edison’s DC. Wow!


Josh,

In edison's day, they had no practical way to step up the DC voltage
to make it efficient to use for long distances.  The stepped up
AC (using a transformer), was more efficient to use than the low
voltage DC.  The inefficiencies of AC were more than made up
for by the much higher voltage of the AC.  When the voltage is
higher, the current is lower, and the losses are lower for a given
wire diameter.  Today, modern semiconductor technologies
permit the DC to be efficiently stepped up or down.  This ability
to step up the DC voltage is what tips the balance
in favor of a DC long distance power transmission system.  

Cheers,
John