It could be that the Model S has higher "idling" losses than other EVs, but I believe that city driving especially affects the range of this heavy vehicle because you lose a major part of the kinetic energy during braking, even with decent regen. So, the fact that it is heavy and (by my calculations of a couple years ago) this amount of weight accelerated from standstill to 60 MPH is equal to a full mile in range - in city you won't accelerate that fast, but accelerating 4 times to half that (30 MPH) is the same energy, and most of that is lost when braking, so a sequence of stop signs or traffic lights or stop and go traffic will cause the additional loss of kinetic energy, on top of the energy used for propulsion. Lighter vehicles are able to accelerate similarly with lower energy investment and thus the loss is also lower, making light vehicles more likely to do well in City driving if reduction in friction from low speed cancels the added losses from braking and accelerating. That is also why countries and cities with tram/metro/light rail use vehicles with low mass for the frequent stops. In Netherlands they even special-built a "Sprinter" train that is used for the service that stops at all stations (rightfully called "stop-train" in the Dutch language) and it is designed to regen power back to the catenary as well as being as light as possible while still allowed on the national railways. The "inter-city" type long distance trains are much heavier and longer since fast acceleration and resulting power loss is less an issue.
Cor van de Water Chief Scientist Proxim Wireless office +1 408 383 7626 Skype: cor_van_de_water XoIP +31 87 784 1130 private: cvandewater.info http://www.proxim.com This email message (including any attachments) contains confidential and proprietary information of Proxim Wireless Corporation. If you received this message in error, please delete it and notify the sender. Any unauthorized use, disclosure, distribution, or copying of any part of this message is prohibited. -----Original Message----- From: EV [mailto:[email protected]] On Behalf Of EVDL Administrator via EV Sent: Tuesday, May 03, 2016 12:47 PM To: Electric Vehicle Discussion List Subject: Re: [EVDL] EVLN: Upgraded 2016 Tesla-S 90D is the first 300mi/483kmproduction Electric car On 3 May 2016 at 8:53, tomw via EV wrote: > The S uses quite a bit more power on accessories than most conversions, > and most drivers likely usually have climate control on. But that wouldn't affect EPA range ratings, would it? Aren't those measured with aircon and other stuff turned off? Or is it burning off energy on accessories that CAN'T be turned off? That would kind of stink. :-( > It also has a very low drag coefficient, so low that it has the same > CdA as my little Suzuki Swift. That, and its 4700+ lb weight results in > its drag and rolling resistance forces being equal at around 60-65 mph > compared to around 45 mph for most vehicles. Yeah, I'd forgotten, it's (please forgive me) an obscenely heavy car. So friction losses are dominant. Hmm. > The energy/mile used moving at ~ constant speed in city driving would > have to be low enough relative to highway driving to compensate for > that energy lost during each acceleration, and that will depend on > distance driven between stop/starts. Here again, the EPA method enforces a formula. So I wouldn't think this would affect Teslas more than other EVs. What is incontestable is that the Leaf's city range is greater than its highway range, but the Tesla's city range is SHORTER. It's hard to avoid the notion that a Tesla acts more like an ICEV than other EVs do, wasting a significant amount of energy "idling." Ouch. David Roden - Akron, Ohio, USA EVDL Administrator = = = = = = = = = = = = = = = = = = = = = = = = = = = = = EVDL Information: http://www.evdl.org/help/ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Note: mail sent to "evpost" and "etpost" addresses will not reach me. To send a private message, please obtain my email address from the webpage http://www.evdl.org/help/ . = = = = = = = = = = = = = = = = = = = = = = = = = = = = = _______________________________________________ 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) _______________________________________________ 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)
