Paul, It looks like the confusion is about... two different things. On the average, over a whole trip, all the braking that you do might return 5 or 10% of your total energy invested in the trip, so regenerative braking can extend your range by that percentage on average over a whole trip.
The ~50% that was mentioned in the article is the instantaneous power or energy that is recycled on one application of the brakes: the efficiency of the batteries, controller, motor and drivetrain results in a number of losses, all added up twice (regen and acceleration) will give you about half the energy for acceleration that you started with before braking. I think Click-n-Clack did a pretty good story about that. Hope that I clarified the difference, 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: EV [mailto:[email protected]] On Behalf Of Paul Dove via EV Sent: Tuesday, October 28, 2014 4:40 AM To: brucedp5; Electric Vehicle Discussion List Subject: Re: [EVDL] EVLN: What Click-n-Clack know about regen (?) You get no where near that much energy back. 5% on average. Do the math regen produces a few amps and acceleration uses hundreds of amps. Sent from my iPhone > On Oct 28, 2014, at 3:57 AM, brucedp5 via EV <[email protected]> wrote: > > > > 'REGEN SPREADS TO SUSPENSION SYSTEMS' > > http://www.greatfallstribune.com/story/life/2014/10/23/click-clack-slow- steady-wins-race/17804227/ > Click & Clack: Slow and steady wins the race > October 23, 2014 > > Dear Tom and Ray: > > I am always irritated by people who have their accelerators pressed right up > until the moment they apply the brakes. For example, I might be a half a > block from a red light and will start coasting in anticipation of the stop. > Someone behind me will swerve into the left lane, accelerate past me and > then I will pull up next to him at the light, having lost the race. This, it > seems to me, is a great way to use extra gas. But with the new regenerative > brakes on electric and hybrid cars, it may no longer be such a stupid > maneuver. What percentage of the energy a car uses to accelerate is gained > back via regenerative braking? I'm guessing about half, but if it's 90 > percent, it might not make much difference anymore if you drive stupidly, at > least from a cost standpoint. - John > > > TOM: Yeah, it's still a stupid way to drive, John. > > RAY: Cars that use regenerative braking can capture half, or even a little > more than half, of the energy that would otherwise have been lost to heat > during braking. That's a wonderful thing, no doubt about it. > > TOM: But if you keep spending a dollar and getting back 50 cents, you still > will go broke eventually. It'll just take longer. > > RAY: "Regenerative braking" is kind of a misleading term, because it doesn't > really apply to the brakes, as we think of them. > > TOM: What it does is use your car's wheels, which are already turning, to > generate electricity. That electricity can then be sent to a battery, where > it can be stored for later use. > > RAY: When the wheels are powering the generator, the generator provides > resistance, so the wheels naturally slow down. That's the "braking" part of > all this. > > TOM: And what's so clever is how hybrid- and electric-vehicle makers use > both that resistance and the traditional brakes to slow and stop the car. > > RAY: When you step on the brake pedal, the car's electronic braking > controller determines how much braking is needed, how quickly, and how much > electricity the battery can accept and store at the moment. Then it figures > out whether to get the braking from regeneration, the mechanical braking > system or some combination of the two. And if it's done well, with > well-designed software, you, as the driver, don't know the difference. > > TOM: So, when you race ahead to a stoplight and then hit the brakes at the > last minute in a car with regenerative braking, you do recoup some of that > energy that would previously have disappeared as heat from the friction of > the brakes. But you don't get all of it. > > RAY: In fact, the more urgently you need to stop, the more likely the > mechanical brakes will have to be called into action, which means you'll get > even less recouped through regeneration. > > TOM: So we don't recommend this style of driving, even if you have a hybrid > or electric car, John. > > RAY: Here's the final reason why: Even if you don't waste as much energy as > you appear to be wasting, you still feel like a jerk when the guy you > annoyingly raced past pulls up next to you at the light with a smug look on > his face and smiles at you. > > Got a question about cars? Write to Click and Clack at www.cartalk.com. > [(c) greatfallstribune.com] > ... > http://www.dispatch.com/content/stories/business/2014/10/25/regeneration -not-a-license-to-drive-dumb.html > Car Talk: 'Regeneration' not a license to drive dumb > By Tom and Ray Magliozzi October 24, 2014 > ... > http://www.southbendtribune.com/click-here-for-story/article_c37a5697-59 6c-5bfe-b43b-827fde50404b.html > RAY: "Regenerative braking" is kind of a misleading term ..." > October 26, 2014 > > > > [dated] > http://earthtechling.com/2013/09/regenerative-energy-car-tech-spreads-to -suspension-systems/ > BY NINO MARCHETTI SEPTEMBER 4, 2013 > REGENERATIVE ENERGY CAR TECH SPREADS TO SUSPENSION SYSTEMS > ... "the world's first fully active suspension system with energy recovery > function." ... > > > > > For EVLN posts use: > http://www.evdl.org/archive/index.html#nabble+template%2FNamlServlet.jtp %3Fmacro%3Dsearch_page%26node%3D413529%26query%3Devln+-re%26sort%3Ddate > > http://www.businessgreen.com/bg/feature/2376392/electric-cars-scheme-aim s-to-spark-a-revolution-in-yorkshire > S. Yorkshire.uk incentive scheme integrates EVs into business fleets > > http://www.eetindia.co.in/ART_8800705576_1800008_NT_e1cb9076.HTM > Siemens' Sivetec-MSA3300 integrated inverter+motor-in1case powertrain > ... > http://cleantechnica.com/2014/10/24/siemens-developed-new-ev-motorinvert er-combination-cuts-costs/ > New Siemens EV Motor+Inverter Combination Cuts Costs > > http://www.niagarathisweek.com/news-story/4917035-get-a-charge-free-of-c harge-at-ball-s-falls/ > Get a free EVSE charge @Ball's Falls.ca > + > EVLN: 'Oh Lord, won't you buy me an Electric Mercedes Benz' ... > > > {brucedp.150m.com} > > > > -- > View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/EVLN-What-C lick-n-Clack-know-about-regen-tp4672246.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) _______________________________________________ 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)
