When you study mechanical work and energy and thermodynamics as a mechanical engineer, you diagram all the parts in the system and you are careful to "draw a box" around the portion you want to analyze. You always need to recall what is outside the box for a true analysis, but often the economy of a process is in a smaller box and losses outside it can be ignored.
Like the earth sun system where the sun raises water into the atmosphere for free, at least in the near tern. The sun is running down and creating much entropy but we need not care. But for the operation of a drag line (lowers or raises ore by a cable system and a shovel) or big yukes burning diesel, or some EV truck. You look at it whichever way you can comparing losses and regenerations to see which system makes sense. So Fred's noting the loading at the top, is drawing the box around a different system. It might be worth considering how that is done if it takes more to load the EV than some other method then the EV might be giving a false impression of system efficiency even with the regen. Could be that comes out in the cost of the EV to begin with. If it is a new fangled thing, its economies of scale could be degrading the EVs from a strictly bottom line economics POV. On Sat, Mar 19, 2016 at 3:24 PM, fred via EV <[email protected]> wrote: > I'm surprised that no one has brought up, literally and figuratively, the > energy involved in making that big truck work "better" going downhill. > Doesn't the description of the activity imply that elsewhere (top of the > mountain) is a loader or loaders filling the vehicle up with potential > energy? There would be payloaders, belt systems, some form of huge > dispenser of mass creating or moving the material that has to be moved to > the bottom. > > As with water generated power, there has to be a source. In this case, the > source is overlooked, but that's okay. > Also, there's no reference to inherent efficiency losses. That aspect is > all too often ignored, especially from people who tell me I should build a > generator into my spare tire and run it while I drive, to recharge my > battery pack! > I'm sure everyone here recognizes that there is still a net loss and in > the case of the loading equipment, I'll venture to guess that it's a severe > net loss. > fred > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20160319/37c04274/attachment.htm > > > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > Read EVAngel's EV News at http://evdl.org/evln/ > Please discuss EV drag racing at NEDRA ( > http://groups.yahoo.com/group/NEDRA) > > -- 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) 585-6737 Land (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Mobile and Google Phone [email protected] <[email protected]> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20160319/8e0f67de/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
