Talk:Smart electric drive

Switch generations? Role of Zytek?

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I added a section for the second-generation Tesla battery-powered version. The Zytek announcement is quite old, second-hand, and it's unclear if any of the planned leasing and production happened before late 2009 when the second-gen will roll out. -- Skierpage (talk) 21:55, 22 August 2009 (UTC)Reply

Any idea on why the motor power was de-rated and the max speed therefore decreased? 27hp will only get you about 70mph on a cruise, flat out in still air... and 40 would either briefly get you 85ish MPH after a minute or so's acceleration, or maintain 70 up a moderate incline for a couple miles, or against an intermittent headwind. Hence their limiting it to 62mph is understandable to avoid burn-out should users try and charge up too many hills at full pelt... but the reason behind the power reduction itself which has these knock-on effects is not. The car now effectively has the performance of an old Fiat 126 with a low-flow NOS system that only accepts quite small gas cylinders... and Fiat didn't even bother trying to sell that car in the USA! Performance seems a bit patchy in modern european terms, even. 193.63.174.11 (talk) 11:56, 21 April 2011 (UTC)Reply

Standard 220V outlet?

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What would a "standard 220V outlet" be (under the Second Generation Specifications)? Wouldn't it depend on amperage? —Preceding unsigned comment added by Sfisher (talkcontribs) 02:48, 7 July 2010 (UTC)Reply

In the UK and Europe, it's between 10 and 15 amps depending on your area (13, UK). So they've probably erred on the side of 10A, and I would expect it's similar in the USA (a bit less risky than a 20A 110V socket). That's the spec I've seen for a few other 220V chargers anyway. 2.2kW is a bit rubbish (even vs the 2.99kW with UK domestic plugs) so I'd be surprised if a quickcharge option doesn't come along at some point. 193.63.174.11 (talk) 11:58, 21 April 2011 (UTC)Reply

Does the Smart fortwo ED use regenerative braking?

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Does the Smart fortwo ED use regenerative braking? Info on the "Technology" and "FAQs" pages at: http://www.smartusa.com/electricdrive/?src=hp seem to indicate that the brakes are the same as the non-ED version, thus no regen braking. If so, this is a definite negative that should be pointed out in the Wiki page.

Phantom in ca (talk) 13:51, 1 August 2010 (UTC)Reply

Regenerative braking is a function of the motor, controller and charge system, rather than the actual brakes, though there may be a joint controller that works in tandem with, e.g. the ABS system to regulate the manual brake force balanced against the regen.
However given that Smart have pulled other tricks such as adding a simplistic stop-start system and calling the car a "micro hybrid", I wouldn't put it past them forgoing regen on their electric car. 193.63.174.11 (talk) 12:00, 21 April 2011 (UTC)Reply
 
Smart ED interior

All Smart electric have regen braking, some even with paddles at the wheel. Look at the right gauge which shows power. In the photo, it is switched off at about 8 o'clock position, same as other gauge for SoC. When ready, needle will go vertical to 0 at 12 o'clock position. Power then goes up to 3 75%, kickdown to 4 100%. Regen goes negative, 11 or 10 while off the accelerator, and to 9 when touching the brake pedal or the wheel paddles.  Matthead  Discuß   16:39, 18 April 2021 (UTC)Reply

MPG rating

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I wonder if other countries have done their own comparitive-economy tests for this car and produced different figures? The US one (as I already noted on the rating sheet photo page) seems pretty distorted and unfair on electrics. In short, it assumes that your gasoline car gets 100% of the chemical energy out of a gallon of gas, and is also a very small hatchback with impressive economy.

In reality, if you drive such as to use 33kW in an hour, you may cover 90 miles. If you're very good and drive far slower (40-50mph at best), you MAY double that. Getting 3x that figure, currently, requires use of a motorcycle and travelling at no more than city speeds.

What they're saying here is that the Smart's battery pack is equivalent to 1.3 gallons when it's actually more like 0.4... it's energy efficiency is quite a bit higher than they give it credit for. The euro, stop-start diesel version can achieve almost 90mpg (UK) and puts out mid-80s grammes per km CO2, but also maintain 45hp if you ask it to - and in doing so, keep up a pace of over 80mph for hours on end. In the face of that, if the electric only manages to make it up to 90-ish (US, granted) in exchange for a higher price and all those compromises, why bother? 193.63.174.11 (talk) 12:05, 21 April 2011 (UTC)Reply

More US MPGe rating issues

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Further to the ^ above ^ but I didn't want it to be just a footnote given how long it's been and how striking it is.

I was trying to use the figures shown here as the basis for a rough thought experiment of my own regarding a potential hybrid vehicle and noticed a rather strange discrepancy:

European version claims a 16.5KWh battery back (or 14, in the body text, but that must have been upgraded since?), which matches reasonably well with the claimed 135km @ 120Wh/km (16.2KWh) and 84mi @ 200Wh/mi (16.8KWh; presumably the "200" is an oversimplification in converting from the metric, and should be more like "192", which gives 16.1...).

However, the American one says a whopping 390Wh/mi, about twice that of the European rating, and although the estimated range is lower, that would still demand an almost 25KWh battery pack. Even the best-case scenario (63mi at 94MPGe, with 1 US Gal = 33.7KWh) calls for a 22.5KWh battery; that distance at an average 87 or highway 79 would need 24.4 and 26.9KWh; and Smart's own claimed 98 mile best-case range, at 94MPGe (as they have not published a matching MPGe or Wh/mi figure) would require a huge 35KWh pack.

What's going on here? Does the American model somehow have much higher energy demands, and a larger battery to match? Or have they made a serious error of calculation, possibly on purpose to massage the MPGe figures down to a level less embarrassing for domestic rivals?

It may just be a metric/standard cock-up again, though. The difference between the stated figure and one that would match with the actual battery spec is approx 1.5x ... or with some fudging, it might be the 1.61x difference between miles and kilometres. Maybe someone got confused along the way and multiplied out a number they were given, thinking it was Wh/km when it was already Wh/mi?

The Euro figure seems fairly realistic; worked out at 60, 75 and 90km/h (37, 47, 55 mph), the motor would be exerting 9.6, 12.0 and 14.4hp, which are within typical continuous power requirements for a fairly aerodynamic car, particularly at the lower end.

Even flat out at 100km/h, the American "390Wh/mi" (242 Wh/km) works out to a little more than 32hp, a figure that the motor and electronics can't even sustain continually, maybe not even for the half hour it would take to completely drain the 16.5KWh pack (as it is halfway between the 26.6hp "indefinite" figure and the 40hp "two minutes max" one). 32hp is more like the amount of power required to sustain 75mph+ speeds. However, I don't think they've even recycled the figures from the first gen model; 75mph at 390Wh/mi would demand almost 39hp continuous, close to the system's maximum short-term overboost rating, and itself usually good enough for over 80mph (the gas-powered version could sustain mid-80s speeds with 40 and 45hp engines). Even working back from 30KW, that's 77 miles in one hour.

Unless you're climbing a long freeway hill at the usual maximum allowed gradient (bear in mind it's hard-limited to 100km/h - when I drove one, the GPS never went above that (106 on the speedo) and it sometimes chose to top out a little lower (103k speedo / 97 GPS - still just above 60mph), yomping up a mountain pass, facing into a strong headwind, or doing a rather violent cross-town run with braking forces that routinely exceed the regenerative capacity (seeing as "urban" is rated as more economic than "highway", you're working well outside the bounds of the normal test, here) you can't actually MAKE the car expend the (average) amount of energy they've rated it for. Burning through that much at 20KW would involve blowing an average 27hp to achieve just 51mph. Which if I hark back to my early driving days, would require some moderately stiff terrain - equivalent to hustling my old 1-litre through the welsh hills at a similar speed, foot mashing the throttle hard to the floor, and skipping between 4th and 5th gear (with an option on 3rd if I wanted to overtake and reach 60...70... or more). Typical economy tests don't tend to have large portions dedicated to that kind of forthright progress.

(If we assume an extraneous metric -> imperial conversion, 242Wh/mi at 20KW = 82.6mph ... it's gone rather the other way! A 27hp car which could go that fast would be impressive. At 10KW, it's 41mph... a bit excessive in terms of power-for-speed, but more within the bounds of realism. The closest pass with my back-of-the-envelope calculations is 15KW (20hp) which gives us 62mph, or just under 100km/h. It might then not be unreasonable to assume they ran the test at 55~60mph (55 requires about 16hp?) - somewhat faster, and therefore less economic, than the Euro one - and produced a more believable and mainstream 240~250Wh/mi (only 25% more than the European energy consumption) that someone slipped up and multiplied by 1.61 (or even 1.5?). Of course, this would also mean the MPGe figures go up by a similar amount - a nice round 140MPGe average, for a start, or over 150 urban. Smart's claimed 98 mile peak range is less ludicrous, then; it would still need a 22KWh battery pack under the same test conditions, but if you're driving conservatively and within typical urban speed limits (65km/h or much less, on the whole; as low as 40 or even 30 in some places) with almost complete reliance on regenerative braking, it might be possible to claw an extra 1/3rd distance out of it...)

So ... just how have they figured this car uses so much? Like, as much as a fully loaded 5-seat station wagon version might? Is it considering powerplant-to-road energy use and assuming some rather inefficient transformers, transmission lines, and chargers? Or just sloppy maths? Totally bizarre. 193.63.174.211 (talk) 08:57, 1 May 2012 (UTC)Reply

Mass Production vs. Lean Production

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I take issue with the use of the term mass production in this article. I would find it surprising that an automaker in 2012 would be using an outmoded production philosophy. Can anyone cite this? If I had to guess, they are probably using lean production but I don't have any way to prove it. --Chris Murphy (talk) 20:37, 3 October 2012 (UTC)Reply

The expression mass production is used as a mainstream expression here, meaning they want to make thousands/tens of thousands a year, nothing more. As opposed to limited production or something like that. Aesma (talk) 19:37, 8 September 2013 (UTC)Reply

Tesla Motors battery pack

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Excuse me. I have a question? Did Tesla Motors make the battery packs for the second and third generations or just the second generation? Thanks.--67.54.190.94 (talk) 00:44, 15 December 2013 (UTC)Reply

Just second generation, ED2 2009 to 2011. Third gen was all-Daimler, which they ditched for 4th to get cheaper Renault and LG parts, and now they plan 5th gen Made in China. At that pace, Tesla will provide 6th gen again, probably from Giga Mars.  Matthead  Discuß   16:27, 18 April 2021 (UTC)Reply