Not only the higer curent == higher ineffeciencies, but you have increased drag.
Consider this simple case. You start at the top of a hill and the course makes a perfect circle, dropping at a uniform rate to its lowest point and coming back up at the same uniform rate. Now, starting at the top, you coast downhill. If you downhill speed exceeds the speed you would have travelled on a completely level course, your drag is going to be higher on the downhill. That's a loss proportional to speed-squared and you won't recover it going uphill at a slower speed. Peri -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of David Nelson Sent: 20 November, 2013 4:55 PM To: Electric Vehicle Discussion List Subject: Re: [EVDL] EVLN: Kia Soul EV goes global and aimsfor120-miledrivingrange Michael, It takes a higher current for a motor to push a given vehicle up a hill than on the level thus there is more loss due to inefficiencies. The lower current on the level has lower losses so usually a flat run uses less battery energy than a hilly one. In my Gizmo the difference isn't really that much like it might be with an ICE. On Wed, Nov 20, 2013 at 4:35 PM, Michael Ross <[email protected]> wrote: > Cor, this is really a theoretical topic. Why should a level ride be easier > than a hilly ride if it is a circuit? > > I disagree about regen saving anything except when used for braking, then > you are trading waste heat for some charging.. If you use regen to slow > down on hills you are causing an inefficiency. > > If you are on a hill that is too steep for safe coasting and brakes must be > used, then regen is better than heating your brake rotors. > > If you take all this out of the thought experiment, then hilly and level > are equal. > > > On Wed, Nov 20, 2013 at 7:22 PM, Cor van de Water <[email protected]> wrote: > >> Michael, >> How often do you encounter a steep road that is completely straight in >> the mountains? All the roads in the surrounding mountains that I know >> have sharp turns, for which you will *definitely* want to slow down. So >> except if you are in roller-coaster country, having regen will save at >> least part of the energy from the downhill run when you need to slow >> down for the next turn... >> >> BTW, it may be that the information is skewed due to the redefinition of >> electric vehicle by some manufacturers. I have noticed that my Prius can >> get better mileage going over a large hill than when doing a steady >> speed in flat terrain. This is probably similar to the "Pulse and glide" >> hypermiling technique. This has of course nothing to do with pure >> electrics, but since GM calls their plug-in hybrid an EV, that may be >> where the confusion comes from... >> >> Regards, >> >> Cor van de Water >> Chief Scientist >> Proxim Wireless Corporation http://www.proxim.com >> Email: [email protected] Private: http://www.cvandewater.info >> Skype: cor_van_de_water Tel: +1 408 383 7626 >> >> >> -----Original Message----- >> From: [email protected] [mailto:[email protected]] On >> Behalf Of Michael Ross >> Sent: Wednesday, November 20, 2013 3:51 PM >> To: Electric Vehicle Discussion List >> Subject: Re: [EVDL] EVLN: Kia Soul EV goes global and aims >> for120-miledrivingrange >> >> I am not talking about regenerating. The net change in gravitational >> energy is zero on a round trip. I am talking comparing level to hilly, >> and >> that is all. Drive around the circuit, go steady on the level course, >> only >> brake at the end,; on the hilly course, coast down hills so you don't >> waste >> on regenerating (there is inefficiency if you regen, but if you just >> reduce >> power or coast that is fine). There is no difference between level and >> hilly - except - if you hit higher speeds going downhill you have more >> wind >> resistance. Change in SOC ought to be the same either way. >> >> I am not sure why you want to regen on the downhills... that will queer >> the >> deal. Regen for braking that is what is for. >> >> >> >> >> >> >> On Wed, Nov 20, 2013 at 6:17 PM, rayfellow <[email protected]> wrote: >> >> > What I've heard is that amount of energy captured going down hill >> (regen) >> > results in power to the wheel of about 30%. There's power lost at >> each >> > step >> > along the way - generating electricity, storage, release and then >> power to >> > the motor. The net result is 30%. >> > >> > >> > >> > >> > >> > >> > -- >> > View this message in context: >> > >> http://electric-vehicle-discussion-list.413529.n4.nabble.com/EVLN-Kia-So >> ul-EV-goes-global-and-aims-for-120-mile-driving-range-tp4666302p4666339. >> html >> > Sent from the Electric Vehicle Discussion List mailing list archive at >> > Nabble.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 >> >> [email protected] >> <[email protected]> >> -------------- next part -------------- >> An HTML attachment was scrubbed... >> URL: >> <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20131120/e78a >> f08a/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) >> >> _______________________________________________ >> 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 > > [email protected] > <[email protected]> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20131120/59062773 /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) > -- David D. Nelson http://evalbum.com/1328 http://www.levforum.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) _______________________________________________ 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)
