You asked, "I thought I²R heating was greater for DC. I am not an EE so this is not a rhetorical comment. " NO, if the power factor (Phase angle for ac voltage to current) is perfect, the losses due to current squares times circuit resistance, are exactly the same for AC and DC, but if the phase is shifted, Power factor greater than the desirable perfect, then losses are greater for AC than DC. And perfect is uncommon...
*Dennis Lee Miles * *Director **E.V.T.I. Inc.* *E-Mail:* *evprofes...@evprofessor.com* <evprofes...@evprofessor.com> *Phone #* *(863) 944-9913* Dade City, Florida 33523 USA On Wed, Jun 25, 2014 at 7:18 PM, Michael Ross via EV <ev@lists.evdl.org> wrote: > I thought I²R heating was greater for DC. I am not an EE so this is not a > rhetorical comment. > > > On Wed, Jun 25, 2014 at 3:11 PM, Robert Bruninga via EV <ev@lists.evdl.org > > > wrote: > > > > [the main] reason we have AC transmission > > > is due the difficulties sending DC over long distances. > > > > But for very long distances, high voltage DC now wins. At very long > > distances AC transmission is inefficient due to capacitance (and much > > shorter when underground or underwater). AC also has additional Peak vs > > RMS > > IsquareR losses. > > > > On the other hand, DC loads the line capacitance once, and then it is no > > longer a problem and it can operate at the peak voltage rating of the > line, > > not the average. Hence less overall loss for DC for the same conductor. > > > > But DC conversion does cost more. Hence the tradeoff. DC is now needed > > for > > very long point-to-point transmission which is what we now need to get > > inter-regional transmission of power from Wind. (Solar is not involved > > because it can be generated anywhere at the load for less cost than > trying > > to bring it in 2000 miles from Arizona). > > > > Bob > > > > On Wed, Jun 25, 2014 at 12:02 PM, Robert Bruninga via EV < > > ev@lists.evdl.org> > > wrote: > > > Somebody has to pay for road repairs. > > > Pipelines are a different issue. > > > > Rather than spending $billons of dollars on a pipeline monument to the > > past, it is better to make that same investment into electrical > > transmission lines for now and the future instead. > > > > The only thing holding back a near infinite supply of FREE renewable > > energy is the lack of the long haul transmission lines to get the solar > > and wind energy from where it is abundant (the plains) to where it is > > needed. Pipelines do the same thing for oil but are an ultimate > dead-end. > > > > Anyone want to invest in finding a way to send copper conductors through > > old pipelines to convert obsolete pipelines to underground DC > transmission > > lines? > > > > Bob, Wb4aPR > > _______________________________________________ > > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > > For EV drag racing discussion, please use NEDRA > > (http://groups.yahoo.com/group/NEDRA) > > > > > > > > > > -- > > Put this question to yourself: should I use everyone else to attain > > happiness, or should I help others gain happiness? > > Dalai Lama > > > > Tell me what it is you plan to do > > With your one wild and precious life? > > Mary Oliver, "The summer day." > > > > To invent, you need a good imagination and a pile of junk. > > Thomas A. Edison > > > > A public-opinion poll is no substitute for thought. > > Warren Buffet > > > > Michael E. Ross > > (919) 550-2430 Land > > (919) 576-0824 Google Phone > > (919) 631-1451 Cell > > (919) 513-0418 Desk > > michael.e.r...@gmail.com > > _______________________________________________ > > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > > For EV drag racing discussion, please use NEDRA ( > > http://groups.yahoo.com/group/NEDRA) > > > > > > > -- > Put this question to yourself: should I use everyone else to attain > happiness, or should I help others gain happiness? > *Dalai Lama * > > Tell me what it is you plan to do > With your one wild and precious life? > Mary Oliver, "The summer day." > > To invent, you need a good imagination and a pile of junk. > Thomas A. Edison > <http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html> > > A public-opinion poll is no substitute for thought. > *Warren Buffet* > > Michael E. Ross > (919) 550-2430 Land > (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google > Phone > (919) 631-1451 Cell > (919) 513-0418 Desk > > michael.e.r...@gmail.com > <michael.e.r...@gmail.com> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140625/cc50060b/attachment.htm > > > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > For EV drag racing discussion, please use NEDRA ( > http://groups.yahoo.com/group/NEDRA) > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140625/91225cc4/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
