I too, hate to brake. Benefits include: Mny years ago (before EV and regen was common) I was told by my car dealer that my brake rotors needed replacement - although they were still within the legal limits, he suggested that they would not last that year without wearing thinner than legal (this was in The Netherlands several decades ago they already had a yearly mandatory vehicle safety check). 4 years later I was still driving with the same rotors and they were still legal.... In my EV (without regen) I have no choice but to brake to stop, so I try to be considerate to the traffic around me and still maximize the coasting down and trying to hit the lights when they turn green. This morning I again had the joy of seeing the lights turn red from the distance. I know this light cycles quickly. Someone driving in the next lane passed me, then cut into my lane so I took my foot off the accelerator a little earlier than when I have a clear shot at the lights and again I noticed - that other person kept driving to just before the light, braked hard to stop and a couple seconds later it turned green and he took off again, all the while I had coasted down from 35 to still over 25 MPH while approaching and I only needed to accelerate a little to get enough speed to make it again to the next (red) light (which has a long cycle, so I knew I had to stop, so I approached with as low speed as possible without annoying other traffic)
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: Monday, March 17, 2014 12:01 PM To: Electric Vehicle Discussion List Subject: Re: [EVDL] How can regen be a reason to buy or not? : EVLN: Fiat 500e EV> close to perfect I know on an E Bike the time spent braking is almost nil. You naturally conserve you effort by coasting as much as possible and trying to hit lights on a roll. Using brakes is a great disappointment. The same is true for downhill runs - you mostly want to go as fast as you can, regen would counter that - a lot. I am in the camp that regen is an expensive waste of $ on an human powered, electric assist vehicle. When I am driving a car, it is not that different. I mostly try not to rush ahead only to stop quickly, and sometimes I can make my commute with almost no braking. That total time on a 40 minute drive - couldn't be more than 5 minutes. If I am right, that is 12.5% of time. The inefficiency would then take half that away My estimate of braking time is probably quite high, but I don't know how much. I would guess no more than 6% return from regen. On Mon, Mar 17, 2014 at 2:03 PM, Peri Hartman <[email protected]> wrote: > Tom, thanks for the info. > > I'm not sure what you mean in your 2500' climb: first you say regen put > back > about 24% of the energy and then you say that (or something) was about 1/2 > the potential energy. Are you saying that the regen recouped about 24% of > the energy expended in that scenario? > > I hope my regen is better than 10% in city driving. In your second example > you include some higher speed segments which would add a lot of wind > resistance. My speeds are normally below 30mph. > > Peri > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf > Of tomw > Sent: 17 March, 2014 8:16 AM > To: [email protected] > Subject: Re: [EVDL] How can regen be a reason to buy or not? : EVLN: Fiat > 500e EV> close to perfect > > "/I'll "second" that regen is important. Another example is city driving. > If > you have a lot of hills and stop & go every few blocks, regen can add a lot > of range, even if it's only 70 or 80% efficient. > > I don't have an obvious way to measure this. Has anyone else done so?/" > > I've posted data from my car on diyelectricar a number of times over the > last 4 years. I data logged battery I, V, Ah with a TBS gauge, and vehicle > miles, elevation and speed with a GPS. Doesn't seem to affect anyone > though. > As Lakoff, cognitive scientist, says "If the facts don't fit the frame, the > facts are rejected." > > My data indicates that around half of my car's kinetic energy goes into > potential energy in the batteries when stopping. Going down a 9 mile long > hill, around 2500 ft elevation change, the energy into the batteries by > regen was about 24% of what it took to drive up, and about half of the > vehicle's potential energy at the top. On a short drive for a video, where > I drove about 100 yards at 25 mph, stopped at a stop sign, turned left and > drove about 1/4 mile at max 45 mph, turned right onto a freeway on ramp, > accelerated onto the freeway and drove about 2 miles with max 70 mph speed, > exited, stopped, turned right, drove about 1/4 mile, turned right and drove > about 1/2 mile at 35 mph, regen was 10% of the energy used. I've also > measured around 10% on other, longer local trips. > > Summary of some posts here: > http://www.diyelectriccar.com/forums/showpost.php?p=366384&postcount=20 > Would have posted here but can't do graphs/figures here. > > > > -- > View this message in context: > > http://electric-vehicle-discussion-list.413529.n4.nabble.com/EVLN-Fiat-5 00e- > EV-close-to-perfect-tp4668392p4668489.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) > > > > _______________________________________________ > 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... 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