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From: "Matt Emmerton" <matt@gsicomp.on.ca>
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Subject: RE: OT: UPS for FreeBSD
Date: Sat, 29 Nov 2014 16:04:03 -0500
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> On 11/29/2014 12:56 PM, Darren Pilgrim wrote:
> > On 11/28/2014 8:12 PM, Erich Dollansky wrote:
> >> Real high voltage transmission
> >> lines using DC make sense.
> >
> > Someone already tried that.  It doesn't work.  The conductors have to 
> > be impractically large to get a useful amount of current, and the 
> > distance loss is so high you can't build even a metro grid with it, 
> > let alone a regional grid or the long-distance transmission systems we 
> > use now.
> >
> > 
> That is correct Darren - Long distance transmission, even for a scan few
miles is impractical with DC.

You might be interested to learn that many electrical utilities across the
world use DC transmission systems over hundreds or thousands of kilometers.

http://en.wikipedia.org/wiki/List_of_HVDC_projects

Regards,
--
Matt Emmerton