Nov 18, 2015
malcolm Sources: Tesla Model 3 will have extreme aerodynamic design details | Electrek
Other options, mentioned on Teslas cheapest car could be its weirdest-looking - SlashGear
More aerodynamic wheels (narrower?)
Body panels that fit over the rear wheels (could they be transparent without being a pain to keep clean?)
A single fared-in wiper blade
Changes to the underside to improve airflow/use as heatsink for the cooling system
And persuading the authorities to change the rules regarding wing mirrors - I can't see this one happening in the short-term.
I'm wondering if the base car will be normal-looking (with a Cd similar to the S), but some customers can choose some sort of "Slipstream Pack" or "Range pack" which reduces the Cd below 0.2 but does involve visual changes which others might consider too weird for them.
Similar idea to the bodykit modifications for Roadster 3.0.
Essentially, "Lo-drag" becomes just another option like "Subzero weather", "Rear facing seats" or "Ludicrous". Like the rear facing seats, Lo-drag might not be available after-purchase since it could involve structural changes.�
Nov 18, 2015
Xenius It'll be pretty amazing if they can get below, or even AT .20. That said I'm hoping the car isn't ugly, but honestly if that's the worst thing about it then so be it!�
Nov 18, 2015
ItsNotAboutTheMoney Elon Musk previously said that they were unsure of unconventional v conventional, but were leaning to unconventional which would be in a "useful" way and "not just a weirdmobile".�
Nov 18, 2015
JRP3 Under 2 would be really difficult, and really amazing if they can do it. I agree with the idea of a special "aero" package that might add things like wheel covers, that way the general public who might be turned off by such wouldn't have to get them. I'm all about the aero so I'd probably go for it since I'm not expecting a weirdmobile. Of course I also like the look of the VW XL1.�
Nov 18, 2015
WarpedOne Of course. Expect 225 or even 205.
There are other options.
Smaller tire - body gaps, flush wheel design (no big rim holes).
Nope.
Inside wheel well enclosure? Yes.
This change is overrated.
One word: kamm tail.
Edit: remove misquoted text that appeared as mine.�
Nov 18, 2015
malcolm Thanks WarpedOne
Hmmm Kammback
Too weird for me :biggrin:
Aerodynamic long tail improves fuel efficiency 15 percent�
Nov 18, 2015
tga I don't think this could meet all your cooling needs - sometimes you need cooling without airflow (charging/supercharging, A/C in stop and go traffic). Otherwise the Model S could be built without fans and just rely on ram air through the radiators.
Please, no weirdmobiles - in Franz we trust!�
Nov 18, 2015
nikolai I think thinks like body panels over the rear wheels and a conical rear end are very unlikely. I have a colleague that works at Tesla and while he can't tell me anything specific, he has told me that the Model 3 looks really nice and he thinks a lot of people are going to like it. I think that immediately excludes some of the suggested features that would be off-putting to many.�
Nov 18, 2015
electracity I think it would be safer for Tesla to raise price $5-7K than build a non-traditional car.�
Nov 18, 2015
ItsNotAboutTheMoney I think for the Model 3 it would be a financial disaster for Tesla to raise the base price from $35k to $40k in order to be totally conventional. I think that the difference in sales between "reasonably equipped" $40k and $45k would very large.�
Nov 18, 2015
electracity Every purpose built EV produced to date was designed and produced by people thinking it was different but attractive. Including the Leaf.�
Nov 18, 2015
JRP3 I think the vehicle that will represent the future of transportation should be expected to have some unconventional features. As long as it looks good and hits all the performance stats expected it's going to sell like crazy. I don't think most people looking to buy a cutting edge electric vehicle really want it to look "conventional". The grill-less front of the X is likely a precursor to what is coming.�
Nov 18, 2015
ecarfan Lo-Drag: Cd < 0.2
Except the S and X.And the i3.�
Nov 18, 2015
tga Except that the 3 isn't targeted solely at people "looking to buy a cutting edge electric vehicle", but at converting the general public from ICE's. Too much departure from the conventional will hurt that mission.�
Nov 18, 2015
JRP3 Sure, and I don't expect a "weirdmobile", but I do expect Tesla to push the edge at least somewhat, and they will need to if they are targeting sub 2.0 cd.�
Nov 18, 2015
RobStark Tesla will unveil the concept/prototype in March 2016.
They can get feedback. If vast majority hate it they can change it.
If most like but many hate it then they can keep it.
In this case, the minority will grow to like while the majority creates enough demand to keep Fremont and Reno running at max capacity.�
Nov 18, 2015
electracity Leaked Image:
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Nov 18, 2015
Zextraterrestrial looks more like a 'Leafed' image�
Nov 18, 2015
electracity I have to admit I like pickup Leaf. I even like the Leaf. But it isn't the 3 in S3XY.�
Nov 18, 2015
BriansTesla Ford Prodigy was supposed to have a drag coefficient of .20. Not great looking but not that bad.
�
Nov 18, 2015
RobStark The Ford Prodigy uses the Kammback.
In the stylish hands of Franz von Holzhausen it can more than work.�
Nov 18, 2015
ItsNotAboutTheMoney Leaf: distinctive, divisive (bug-eyed)
i3: distinctive, divisive (boxy, two-tone)
Volt: conventional, distinctive, not divisive
S: conventional, not distinctive, not divisive
The Leaf and i3 divisiveness is deliberate: they have to worry about cannibalizing ICEV sales. Tesla doesn't. So they can design something aerodynamic, that while distinctive and different from the norm won't be ugly. Teardrops are not ugly.�
Nov 18, 2015
electracity So the Bolt is designed to not sell?
It's about interior room on a light weight short wheelbase. Well, the i3 anyways. The Leaf is probably about the lack of effective drug testing in the design department.�
Nov 18, 2015
Zextraterrestrial or too much drug testing�
Nov 18, 2015
1208 VW XL1 cd:0.186
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Nov 18, 2015
Rashomon There is such strong incentive for Tesla to hit record low drag numbers. If Tesla reduced the CdA to 0.44 meters-squared (the S is about 0.58 m2) by the mentioned Cd of .2 with a 10 percent reduction in A by narrowing the 3 and eliminating sideview mirrors, they could cut power requirements to maintain 75 mph on level ground to about 14 kW of delivered power. Such a car could easily go more than 225 miles at 75 mph with a sub-60 kWh battery pack, even accounting for coulomb losses and drive train losses. They could probably deliver a M3 that hit an EPA range rating of 240 miles with a pack around 50 kWh. It suggests the pack sizes might end up at 50 kWh base and 65 kWh optional, the bigger giving almost 300 miles of EPA range.�
Nov 18, 2015
Candleflame you know i have a feeling the rearwheels may be covered like in the XL1 and the car will use special aero tires in the front... The cd reduction would be huge.�
Nov 18, 2015
ItsNotAboutTheMoney And did the i3 have to look like it does on the _outside_?
The Bolt is designed just to sell enough. GM is only going to make 30k of them per year. It's primarily an LG Automotive development vehicle with a GM designed motor, assembled by GM.
See that picture posted of the XL1. That's not even really pushing the boundaries. But the XL1 is a hybrid.�
Nov 18, 2015
hobbes Another article reporting insider info was posted on the short-term thread:
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Nov 18, 2015
BriansTesla Wonder if the M3 might have any elements of this 1992 GM ultralight (.192 CD). Wouldn't that be something.
�
Nov 18, 2015
Trev Page "no weirdmobiles"
Model 3 has been vacillating between "radical" and "conventional" even as recently as the Detroit auto show earlier this year. The design direction is most likely finished now to be able to start construction of the prototype in time for the March unveiling I certainly doubt out of the gate that Model 3 will be radical. I'm pretty confident the Model X front end will be there, the rest... I expect to see something that fits in the same family as the Model S to begin with.�
Nov 18, 2015
MrBigSmiles 
Like this?
�
Nov 18, 2015
aronth5 A financial disaster very doubtful. Some said the same thing when Tesla discontinued the initial low end Model S that started at $57,999. As long as the Model 3 is roughly half the cost of the Model S it will sell extremely well.�
Nov 18, 2015
ratsbew Getting rid of the side mirrors kills two birds with one stone. It would reduce the Cd and the CdA. I hope they are designing for a Cd of 0.20 with mirrors and then it will be a bonus if they can delete the mirrors to get down to 0.19 or so.�
Nov 18, 2015
Mr X I can't imagine Tesla making an ugly vehicle
Model X is the "least" attractive vehicle in their line up but only because its a CUV/SUV, taller shapes are never attractive because of all the excess body.�
Nov 19, 2015
1208 Personally I find the roadster the least attractive. The X has elegance for its size.�
Nov 19, 2015
malcolm Tesla Model 3 design: Expect the unexpected | BGR
It's an old comment from Elon, but if it "won't look like other cars" some people are bound to find that weird.
We know that Model 3 is a new platform rather than a single car and so we've speculated about different configurations. Maybe one configuration could be the 0.2 Cd version.
Or is Elon pushing for 0.2 as a standard?�
Nov 19, 2015
Cobbler So take the Model X design, lower it at least 5 inch.
The trunk should follow the bold line all the way down like a Bugatti Veyron and put some wheel covers on from a Prius.
aaaanddd... voila ... Tesla model 3 :biggrin:�
Nov 19, 2015
scaesare I'm not convinced of that...
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Nov 19, 2015
tinm Instead of curb rash on the rear wheels, we can look forward to curb rash on the rear side quarter panels. Fun times ahead�
Nov 19, 2015
pmadflyer That's what autopark is for!�
Nov 19, 2015
scaesare Cd of 0.075... but definitely in weirdmobile territory:
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Nov 19, 2015
kalikgod I would not want to be in there if that hydrogen fuel cell started leaking.�
Nov 19, 2015
scaesare As a plus,it would double as a great coffin you could jettison in a Star Trek film...�
Nov 19, 2015
malcolm With a turning circle the size of Texas, by the look of things.
Do both the front and the single rear wheels steer?
�
Nov 19, 2015
1208 Looks cool. Someone pm Elon it.�
Nov 19, 2015
AWDtsla All things being equal, 80% frontal area combined with this drag number, Tesla only needs a 40kWh battery pack, and with minimum gigafactory price reductions the pack will have a maximum price of $9000, but will probably be much cheaper than that. I would bet actually that their entire powertrain will cost less than a comparable car, i.e. BMW 3 or Audi A4. That's quite an inflection point where both the initial cost and operating costs of the car is less than an ICE counterpart.�
Nov 19, 2015
scaesare The context surrounding the 80% size reduction comments make it likely that it's overall volume that's reduced, therefore just the frontal area would likely be more than 80% of that of a Model S, however.�
Nov 19, 2015
AudubonB Hey! Who are you to call an aardvark weird?�
Nov 19, 2015
ecarfan Hey, those of us who are University of California Irvine alumni resemble that remark
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Nov 19, 2015
ItsNotAboutTheMoney 40kWh would _suck_, because the impact of difficult conditions would be _far_ greater. Heating in cold weather, rolling resistance from rain, crosswinds and so on.
Given that
1) Capacity reduction increases the impact of time-based loads
2) Aerodynamics can be disturbed by crosswinds
3) the key aim of the Gigafactory is to lower cell and battery prices with a target of reaching $100/kWh
4) Tesla's approach has given them an energy density advantage over competitors
5) Higher capacity increases charging power, which increases charging mph, which reduces (a) journey time (b) Supercharging time
6) Higher capacity increases range, which decreases the need for Supercharging which reduces (a) journey time (b) Supercharging time
I think that using aerodynamics as a capacity-cutting measure is absolutely the wrong approach to take for Gen 3. The cost savings would be limited, diminishing as battery prices continue to fall, and it would be at the expense of utility. I think it would be much better to use the aerodynamics in a positive way that also leverages any density advantage to differentiate from more conventional competitors. I'd argue that they'd have more appeal at the value end by cutting back on performance of the base model instead. At the $35k price point there are plenty of cars with 0-60 7s or higher, and that includes very popular BMW 3 Series diesels.�
Nov 19, 2015
AWDtsla We're talking about the base model. You can get 2-4x improvement in heating draw by using a heat pump, which is just the AC in reverse cycle. Rolling resistance and rain will both be reduced by body shape and narrower tires.�
Nov 19, 2015
dgpcolorado Except that heat pumps typically don't work well in very cold weather. Which is when the energy savings is actually needed.
I really hope that the Model 3 doesn't have rear wheel fairings and tight tire/wheel-well clearances. It is tough enough to deal with packed-in snow and ice in conventional wheel wells. Smooth wheel covers, fine. I'd also be concerned with radical designs that have a tapered rear because of greatly reduced space utility and awkward rear hatch access.
Overall, I guess I don't buy the idea that Tesla will hit a < 0.20 Cd for the Model 3. I'd be surprised if they did it.�
Nov 19, 2015
AWDtsla Commercially available air source heat pumps are rated down to -13F. That's technology a couple years old.�
Nov 19, 2015
Mad Hungarian Doesn't the MS already use a heat pump, with resistance as a booster? I would expect this to also be the case for M3, seems crazy to use resistance-only when you look at what that costs in range.�
Nov 19, 2015
ItsNotAboutTheMoney Heat pumps that are rated for low temperatures also don't operate as efficiently in warmer conditions. Those heat pumps also won't necessarily translate to automotive applications. The Leaf's heating system is of little help at lower temperatures.
Fundamental rule is: capacity ~ range ~ power ~ charging speed ~ 1/discharge rate.
In reducing the capacity Tesla would:
- increase the swings in range depending on conditions which means that Tesla
- - needs to build more Supercharger capacity
- lower maximum charging kW which means that Tesla
- - loses the gain in charging mph you could have had from improved highway efficiency
- - adds charging time needed to deal with HVAC and other time-based losses
- - needs to build more Supercharger capacity
- lower average range which means that Tesla
- - needs to build more Supercharger capacity
Not only would the cost savings on batteries be less than $2k per 10kWh, diminishing to $1k (Tesla hopes) per 10kWh, but some of those savings would be lost to higher Supercharger infrastructure costs and the cost of offering the additional pack size.
I sincerely hope that Tesla doesn't have to reduce the pack size to 40kWh to hit $35k. That would be a really bad sign.
- - - Updated - - -
No, the Model S uses heat captured from the motor, which reduces the need for resistive heat.�
Nov 19, 2015
Mad Hungarian Thanks for the clarification.�
Nov 19, 2015
RobStark Rear and/or Front fender skirts can be detachable and optional.
Repaired or replaced after accident.
�
Nov 19, 2015
AWDtsla If your efficiency is above 100%, then it is of use. Maybe you don't get the 300% as usual, but fine. Most winter conditions, it saves a lot of energy.
I think the leaf is of little use, so no valid comparison there.
You're making the assumption they use the same chemistry and cell internals optimized for the same charge/discharge rates. This is not a good assumption. 40kWh also has a huge advantage, which is charge time/circuit size needed at home. All of a sudden 110v charging becomes almost bearable, and 240V charging becomes very fast. That also means 3rd party charging stations also become more useful.�
Nov 19, 2015
stopcrazypp The Leaf system is actually fairly relevant, esp. given the Model 3 will be the same price range. See the discussion here:
http://www.mynissanleaf.com/viewtopic.php?t=12212
Not sure how true it is but that thread says the heat pump equipped Leaf is less efficient when using AC in warm weather.�
Nov 20, 2015
jkk_ Glad I'm not the only one worrying about this...�
Nov 20, 2015
scaesare To clarify... the MS has no heat pump capability. It also does not use waste drivetrain heat for cabin heating, although it does use it for pack heating.
Cabin heat is PTC/resistive only...�
Nov 20, 2015
RobStark 
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Nov 20, 2015
Bangor Bob Well then it's just a crap design. Residential minisplits can have HSPF's of 12, COP's > 1 down to -15F, and SEER ratings in the 30's. No reason a Mitsubishi or Fujitsu 12kBTU minisplit can't be repackaged for automotive use - the outdoor heat exchanger is really the only bulky component.�
Nov 20, 2015
ItsNotAboutTheMoney The Leaf has a "hybrid heating system", i.e. a heat pump, so it's performance is relevant in terms of the technology. Nissan published a graph showing benefit by temperature and it wouldn't help in deep winter morning commutes here.
The car and the Supercharger network have to meet those regular needs.
That does not make sense. If 40kWh is enough for regular driving, then you can charge a 50kWh battery at only a slightly higher rate than the 40kWh for the same effect. (Extra weight reduces efficiency).
And I'm not making comparisons with the S/X battery. I'm simply using the fundamental rule that you can charge larger batteries faster. Tesla has said that they want to speed up Supercharging and there's an obvious need both for capacity and customer convenience. Faster charging is better. More range is better. Both reduce the cost of the Supercharger network. Both reduce OTR charging needs and shorten journey times. Customer gets better utility, Tesla lowers costs. Tesla wants to sell more battery and sell you their Supercharger network. The base model needs to cut out the frills, not the utility. Long-distance BEV is what separates Tesla from the other manufacturers. (Even Audi's 150kW PR blitz is rather light on the network fundamentals, and once again journalists failed to push them on their whole vision of it). There will be more competition from other manufacturers for people who just want a long-range BEV.�
Nov 20, 2015
Bangor Bob A lot of the cues from that ended up in the EV1. The EV1 was a clumsy execution, but the ideas were there. (And it hit .195Cd, as I recall).
There are tiny bits of that appearing in a lot of cars these days - mostly the front-rear tapering greenhouse profile, and a degree of Kammback -ness. One downside of a Kammback is that the rear of the car is always filthy. Also in the winter loose snow accumulates on the vertical rear surface and can obscure the taillights after driving just a few miles.�
Nov 20, 2015
Rashomon It comes down to range miles per minute of charge. A more efficient vehicle, say a more aerodynamic one, will get more miles per kWh of energy. Yes, at the same C rate you can dump more energy into a large pack than a small one. But that doesn't mean a more efficient vehicle with a smaller pack won't actually charge at a faster rate when measured in miles/minute. And it will either cost less or have higher margin for the manufacturer than the less efficient vehicle.
Musk is smart; he's obsessing about CdA for a reason.�
Nov 20, 2015
stopcrazypp Improvements in CdA and other efficiency measures should not come with significant reductions in battery capacity. You end up with a car that gets good range in certain conditions and then a large drop in other conditions. Increasing battery capacity increase range linearly with the capacity in practically all conditions. However, measures for increasing efficiency only work in certain conditions and is less reliable.
Given dropping battery costs and improving energy density, it does not makes sense to start with a small battery pack. Besides from lower charge and discharge power as mentioned, a smaller battery pack also will be stressed more for the same amount of range traveled and will last a shorter amount of miles. I would not expect anything under 50kWh.�
Nov 20, 2015
BriansTesla I think it is worth considering here that many buyers of the M3 might be willing to have less battery capacity to have a car they can afford. They might keep their 10 year old car for road trips and drive their $35,000 M3 for everything else. A couple thousand dollars are important here. Other buyers could still have their 275-300 mile loaded M3.
A 50kwh battery might turn out to be the best number.�
Nov 20, 2015
ItsNotAboutTheMoney Supercharging mph on the S: 85 > 70 > 60. Having 40kWh instead of 50kWh would reduce the maximum charging power by 25%. Cutting 10kWh would not make the car 25% more efficient.
I'm not saying they shouldn't push aero. I absolutely think they should. Aero provides utility. My point is that they shouldn't be using extreme aero as a way to cut battery size significantly, because that has negative implications for utility and for the cost of the Supercharger network.
And one thing I hadn't mentioned was degradation. 70% of 40 is 28.�
Nov 20, 2015
stopcrazypp On the subject of battery cost, difference between 40kWh and 50kWh is 10kWh. At $200/kWh at the pack level every 10kWh costs $2000. Tesla is targeting below $100/kWh in long term with Giga factory which would be $1000 per 10 kWh. That is $1000-2000 difference in cost. How much more money Tesla would have to spend to squeeze another 20% more efficiency out of the vehicle? I'm not convinced it will be significantly less.
Elon has been adamant the car will get 200 miles at minimum in real world conditions. The most efficient EV (the i3) uses 18.8kWh to get 81 miles of EPA range. That's 232Wh/mi. Even assuming absolutely zero buffer (actual battery size for the i3 is 22kWh), that requires 46.4kWh to get 200 miles EPA. While I expect the Cd of the Model 3 to be better (i3 is 0.29), the frontal area will likely be larger. Also Tesla won't be using the extreme weight reduction and skinny tires the i3 uses. I am simply not seeing 200 real world miles from a nameplate 40kWh capacity.�
Nov 20, 2015
AWDtsla Again, we're talking about the lowest end affordable car. $1000 makes a difference. At this price level, you are likely to get buyers who are weighed more heavily on a pure financial decision, they are less likely to max out their options. I for sure see the marketing material boast how much cheaper it is to operate this car versus an ICE.
The effect of weight on real world range appears to be minor, which makes sense if your total efficiency through regen is high, and I expect further refinements to driveline efficiency with the 3rd gen motor/inverter.
Pushing the air around is what takes the most power. It would be silly NOT to focus your engineering effort on fixing the single largest drain of power.�
Nov 20, 2015
stopcrazypp I'm not saying they should not be focused an aero improvements. I'm saying whatever improvements they make should be on top of the pack size (I expect minimum 50kWh). I do not think it is a good idea to use it as a way to cut down pack size to 40kWh. Ultimately I don't think the Model 3 can reach 200 miles real world range with a 40kWh pack, esp. if you are talking about spending less than $1000-2000 to do it. It seems to me much easier to have the pack be 50kWh and it might not even be any more expensive than a car with 40kWh that was optimized extensively.
Aero largely helps highway range, but in mixed driving the weight also plays a role. If you look at a EV efficiency, you will notice Tesla is the only make where highway efficiency is higher than city efficiency.
http://insideevs.com/bmw-i3-bev-official-epa-rating-range-81-mpge-124/�
Nov 20, 2015
AWDtsla Arguing about the final pack size is silly without knowing the engineering that goes into the whole system is silly. I only calculated 40kWh to get an idea of what amount of energy they would need to deliver on 200 miles range. Note That Tesla themselves had almost delivered a Model S in 40kWh. But arguments against supercharging and heating are based entirely on current generation cells and technology. Why assume these will stay the same? Energy and power density are somewhat independently select-able, for example. Especially if you own the biggest battery factory in the world.
They've said repeatedly there will be new technology and it will not be simply a 20% smaller model S.�
Nov 20, 2015
stopcrazypp The 40kWh Model S (160 miles ideal range, 142 miles EPA) was determined to be un-viable though by Tesla. And back then Elon didn't make any hard promises of a 200 mile minimum range (and real world on that). Elon did for the Model 3.
We can throw aside the exact numbers, but given the same chemistry, the power will always go up linearly with the capacity. When you select a power optimized chemistry, the energy density goes down. Those fundamental trade-offs are always there. The reason Tesla was able to make such long range EVs is that they selected the most energy dense cells they can find and made a pack large enough to meet their power requirements. And they reaped the benefits of the larger pack in terms of reduced degradation. Given their commitment to small cell cylindrical, I don't see them straying from this approach. I would be very surprised if the Model 3 pack was not a small cell cylindrical and NCA chemistry.
Model 3 deliveries are planned for late 2017, cell production at Gigafactory originally planned for 2017, but schedule has been pushed up to late 2016. Tesla simply doesn't have the time to pick a radically different chemistry.�
Nov 20, 2015
AWDtsla ~4 years ago for a car that was a Model S, not a Model 3. Again, in the past. Future = different
Power density and DCIR is more related to electrode surface area than chemistry. They reduce cell energy because more of the volume of the cell is dedicated to the electrode vs electrolyte.
They've already changed chemistries twice^H^H^H^H^Hthrice in several years...
You're being very resistant to change...�
Nov 20, 2015
ItsNotAboutTheMoney No he isn't.
Until the 90, the Model S battery packs used a single chemistry, but a different number of cells in 60, 70 and 85. The 90 packs use a newer chemistry. If you want to minimize cost, then having a different cell would be a hindrance because of additional development, manufacturing and support costs. To minimize cost on a smaller pack they'd have to do the same as the S and have the same chemistry, but fewer cells, and then it would charge more slowly, just like the 60 was slower than the 70 is slower than the 85.
Slower charging, less range, less tolerance for poor conditions, higher C rates, lower maximum kW output, higher proportion of Supercharged miles, higher SoC charges, lower SoC discharges, and less tolerance for degradation.
Capacity is the _last_ thing that should be sacrificed to meet price targets.�
Nov 20, 2015
stopcrazypp No, I'm not resistance to change. The only massive change they made in chemistry was from LCO to NCA from Roadster to Model S.
The partial silicon anode on the 90kWh is only a moderate change. I expect a similar moderate change for the Model 3, but it's not going to fundamentally change things such that a 40kWh battery makes more sense than a 50kWh battery (or something roughly in that area as you suggest). Like ItsNotAboutTheMoney puts it, I just think cutting minimum capacity is horrible idea regardless of how chemistry changes.�
Nov 20, 2015
JRP3 We also have to remember they need to lock in a cell chemistry which is fully tested well before the first car is built, so they may have a year or less of more cell chemistry development. As far as minimum pack capacity I've been leaning towards 50kW.�
Nov 20, 2015
Model 3 NO! This is the the the thoughts behind every short-range EV, and the TMS40. Tesla is on a mission to deliver a mid- to long-range EV's that should be able to replace the old fossil burning cars. So no, even the base $35,000 TM3 will be able to go from supercharger to supercharger, witch will say at least > 200km range under (almost) all conditions. The supercharger access may still be an option you have to pay extra for (but I hope not�
Nov 21, 2015
tga This is precisely why I won't buy a "compliance EV" - I have no interest in spending a bunch of hard-earned cash on a car that is useless for almost half of my driving...�
Nov 21, 2015
McHoffa Exactly. There is no point in paying for a Tesla if you can't replace your ICE car 100% of the time. My hope is that in 4 years neither my wife nor myself will ever have to buy gas again. If I can't do a road trip without stopping for hours at a time, I wouldn't buy an EV.�
Nov 21, 2015
pmadflyer This here, is why the model 3 will not have a sub 55 kWh battery. As said earlier, a slippery car increases range in optimal conditions, but does nothing for poor conditions. Only increased capacity can overcome snow, not low friction ties or aerodynamics. I'm betting on a 60 kWh base.�
Nov 21, 2015
ProphetM
++
As Telsa goes downmarket, there will be more and more interested families who don't have two very good cars in the garage. They have one 'nicer' car that they use for most of the driving. The second car is older and higher-mileage and is a commuter car. They replace one at a time, either leapfrogging from one to the other (so the 'nicer' car becomes the beater) or keeping the old beater because it's cheap to keep and is reliable enough as a drive-to-work car.
I'm in this group as well. When we replace a car, the new car is the go-to for anything major. We will not spend 35-50 grand for a brand new car, only to leave it home for a trip in favor of the commuter car with 150,000+ miles on it. That's crazy. It must do double duty or it's not worth buying.�
Nov 21, 2015
physicsfita Let's not forget the downmarket single person -- s/he is likely to only have one car, so it has to be able to do pretty much everything the owner needs.�
Nov 21, 2015
BriansTesla I think it's fine to expect Tesla to meet its stated goals but I think it is a mistake to expect too much for the base model.
What happens next is this.
I won't be happy with the Model 3 unless it has ______________________________.
a 55kwh battery
the ability to do everything my present car does
folding seats
10,000 towing capacity
762hp
on and on and on�
Nov 21, 2015
ProphetM
I'm not saying that the Model 3 needs to go 400 miles on a charge, but a reasonable distance suitable for trips for most people. You'll never cover every case. Psychologically, I think 200 miles is a threshold where it will click for most people. And since 200 'real world' miles has been stated as a minimum, I think that will mean an EPA figure of around 220 minimum. This kind of figure will bring a lot of people into at least considering it, and whether they ultimately decide to pull the trigger will come down to highly specific things like how many trips they make that go over that distance, how long they would be willing to wait to charge, how far they like to drive in a day, whether there are superchargers on their favorite routes, etc. The base model merely needs to get people into the right frame of mind by being comparable to its competitors in most areas and at least feasible in range to a large number of people.
Back on topic - I think they could probably reach .2 but I don't know if they can do it without weirdness in design, and I don't really care. Just like I don't care what the battery size is, I only care how far it can take me. I trust them enough to balance 'efficient' and 'attractive' in such a way that they are pleasing as many people as they can.�
Nov 21, 2015
McHoffa I think the Leaf is proof many people don't care about a little weirdness and I guarantee the M3 will look much better than that�
Nov 21, 2015
stopcrazypp The Leaf is not a very good example because it sells far less than what Tesla is planning. I don't think Tesla can hit their sales goals if the car looked like the Leaf.�
Nov 21, 2015
scaesare This isn't the case for me, nor I expect many 2-car households, which appear make up the vast majority of the county I live in.
A car that serves the majority of my daily driving needs is valuable, even of that means we have to take the ICE for the small percentage of time that we take a road trip the EV won't manage.�
Nov 21, 2015
BriansTesla Exactly! What if the Volt was a pure BEV and had a 200 mile range? How about a 200 mile leaf? They would be selling by the tens of thousands.
I don't think the M3 will be ugly but it won't be a Model S or "look like other cars". I believe it will look like cars of the future and we should be ready for that.�
Nov 22, 2015
electracity Can you name an unconventional aerodynamic car with broad appeal?�
Nov 22, 2015
JRP3 Chevy Corvette?�
Nov 22, 2015
stopcrazypp The C7 is 0.29-0.37 depending on version so it's not particularly aerodynamic. That may be because it is down force optimized.�
Nov 22, 2015
EVNow Musk has stated in the past that 3 won't be a weird mobile. I'd place a lot more trust in that than an unanimous "leak". Of course Musk may be pushing his team to do their best, doesn't mean it will happen or Musk will accept other compromise s.�
Nov 22, 2015
McHoffa I'm just saying as ugly as the Leaf is, it had still sold 170,000 of them as of April 2015. I'm pretty sure Tesla will make the M3 look much better which would give it broad appeal like the Model S. The S definitely has broad appeal but the average car buyer can't afford one.�
Nov 22, 2015
scaesare This is the very reason I've applauded Chevy's effort with bolt....�
Nov 22, 2015
aronth5 I posted a similar statement in a different thread but it actually belongs here
The Model S has a CDa of .24. Is there any reason not to believe that if the Model S had the Model X noise the CD would be .23?
If that is true, and yes that is pure speculation, then maybe they have already made progress as they build a smaller Model S.
I doubt the X nose was done purely for looks.�
Nov 22, 2015
JRP3 That's only part of the equation, aerodynamics is cd x A, and the Vette has a very low A. There is a reason people can get 30+ mpg on the highway when driven conservatively.�
Nov 22, 2015
roblab But they CAN afford troops for oil fields, spills, environmental "disasters", climate change, partially funding ISIS, smog, lung disease, ... Oh, the list goes on. It depends on where their values lie, or if they would rather claim, "Everyone else is doing it, and I can't make a difference."
Sorry. I just hear it too often, I guess.�
Nov 22, 2015
JRP3 The problem is they think they can...�
Nov 22, 2015
Sunlight I think we have the issue of a paradigm shift - EVs benefit far more from better aero than ICE cars as the extra weight of the batteries starts a knock-on effect whereas we have been used to just popping into the fuel station and adding 300+ miles quickly.
So ultimately EVs need to have better aero and revised architecture to get this and to benefit from having batteries and a small electric motor with reduced cooling requirements.
So the front of EVs can change to reflect the new requirements - ditto the overall architecture. This will alter the shape and style of 'ultimate EVs' but we will eventually adapt to the visual onslaught!
Clearly there is a fine line at the moment between exciting and alienating buyers - although I suspect that the public may be more ready for a 'strange change' that we give them credit for..... Especially the young brought up with a different techno viewpoint? 'Ugly' is very subjective..
Can Tesla afford to make a quantum leap and see how the public reacts? Trailblazer or 'conventional' revolutionary?
Maybe there is a case to made for variety of alternatives to be offered to slowly introduce the 'look' - wheel covers; shrouded wheels; alternative nose; revised rear end. The middle cab bit is less affected and rather driven by accommodation/practicality.
Then buyers chose between conventional looks (hopefully stylish and attractive by current standards) and more radical.
Soon we will all be radical. Don't say we won't change! Look at how early cars were made to look like horse-drawn carriages to avoid the 'shock of the new'....
That looks a bit daft now!�
Nov 23, 2015
austinEV "Drive underwater and be a submarine"
Covered wheels, no side mirror, kamm back... The pieces are coming together, right?
Also, this car literally lives in the design studio: (upper right corner, not the circled car)
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Nov 23, 2015
AWDtsla Why assume that efficient must equal ugly? This what everyone else does when they build an "eco" car, like the Prius, or the Murai, or the Leaf. They set the bar of expectations to "So ugly even it's mother couldn't like it" and go from there.
Take wheels for example, there's been about 0 effort into making aerodynamic wheels. The discontinued aero wheels were extremely ugly, but you could also tell they weren't designed with aero in mind. The highest speed part of the wheel was missing an aerodynamic treatment, and there were no aerodynamic shapes in at all, it only just covered the inner spokes.�
Nov 23, 2015
BriansTesla Elon may have something very special in mind. Think Hyperloop.
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Nov 28, 2015
Newb I think we'll see the Kamm back on the Model 3, which has been mentioned here (thanks for the very informative discussion, btw!). Thereby, the Model 3 might have a similar shape to the Mercedes IAA concept (2015) [drag coefficient 0.19, when in aero-mode) :
driving:
Is that a weird mobile to you? To me not - I like it very much.�
Nov 28, 2015
Rafael In my opinion that seems quite awesome!�
Nov 28, 2015
ecarfan Mercedes makes amazing concept cars, but lack the vision and desire to build a decent long range EV production vehicle. Really quite pathetic...�
Nov 28, 2015
JRP3 Get rid of the giant grill on the front end and that would be a sweet ride.�
Nov 28, 2015
roblab I've gotten used to just pulling the car out of the garage every morning and it's fully charged, FREE. Hmmmm. Never could do that with my old gas cars.
People seem to forget that some of those old "conveniences" weren't very convenient. Nearly 500 deaths per year from carbon monoxide, too. And we aren't even going to start on what happens when you go "popping" into a fuel station and it catches fire, or the nearly-every-ninety-second occurrence of cars catching fire on their own.
I can see some benefits to never going to those places to add 300+ miles quickly. Only time I want to add miles while driving is on a trip, and 30 minutes time out while I refresh is time well spent. The world needs to change focus, methinks.�
Nov 28, 2015
McHoffa One thing I am used to right now is traveling from home in NC to just past Orlando FL and only stopping once to refuel between Savannah GA and Jacksonville FL (~400 miles). When we get our S we'll have to rethink how we travel. If we had superchargers at rest areas it might be a bit more convenient. We won't be able to get a 90D for maximum range, so stopping every 200 miles or less for 30-45 minutes to get a partial charge in our 70D will make our trips longer for sure. I think 400 miles per charge (and 30 minutes max to charge completely, a lunch break) would be the sweet spot for regular people to accept an EV and not even think about an ICE car having any advantage. I'm more than ready to switch to a Tesla, but that little difference will take some getting used to. The rest of the year though, I'll never even note that change.�
Nov 28, 2015
jkk_ For me, the sweet spot is around 500km (let's say 320 miles, even a bit less but that would leave enough spare). But in general, I agree with you that 400 miles per charge would be enough for the masses to fully adopt EVs. The charge time can be a bit more forgiving, in my opinion, say 45-50 minutes instead of 30. I have the feeling that most are really slow eaters and I always need to wait for other people to finish their meals ;-)�
Nov 28, 2015
pmadflyer Tesla press conference: 6.2, Autonomous Driving, Musk QA, more - YouTube
Straight from the horse's mouth:
16 minutes in
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Nov 30, 2015
Yggdrasill The more I think about the plan for the Model 3 having a Cd less than 0.2, the more nervous I get.
I just don't believe that it's possible to combine a Cd of ~0.195 with a very good compact family car. If you look at the post by Newb, it's obvious that they've completely sacrifized rear head room. And there's hardly any luggage space.
To get a good Cd, a car pretty much has to be long and low, and when you reduce the length from 5 meters on the Model S, to maybe 4.5 meters, and also reduce the height, there's barely any volume left! The Model S is already one of the lowest cars out there.
I *really* hope the Model 3 can also come as a station wagon or crossover at launch, with a Cd more in the area of 0.25, so that the families that need to be able to occasionally carry 3-5 adults and lots of luggage also have an option. It would be fine to sell the less aerodynamic version with the largest battery only.�
Nov 30, 2015
Kevin Harney Jumping to lots of conclusions there. I believe that the Model 3 will seat five adults and have more luggage space than a BMW 3 Series with both the trunk and the frunk. Models S and X have WAY more storage space than any of the competitors do. Have no fear Grasshopper Franz and Elon will come through.�
Nov 30, 2015
RubenZoe Tesla has much work ahead, but as we can see in the video of Mercedes, with a free front of obstacles in the air flow, a fall from the ceiling and and aerodynamic wheels is enough to get that Cd less than 0.20�
Nov 30, 2015
SarahsDad I like the Mercedes concept. Model 3 won't need so much room under the hood, so I suspect it will have a more "sloping" nose a la 1992 GM Concept Car. Doubt the Mercedes' active rear extension would make it to production though.
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Nov 30, 2015
Model 3 I just love that one! The UltraLight! Yes, it's a weird-mobile, but a weird-mobile I easily could see my self driving around in - if it only was an BEV. I was stunned when I first found out that it was fuelled by gasoline! It just beg to be electrified...
... I even watched "Demolition Man" just to see this car in action�
Nov 30, 2015
jscholl I'm not sure a more sloped hood would be possible, given today's stricter pedestrian safety standards.�
Nov 30, 2015
Yggdrasill I don't think that's a big problem. You just install an airbag under the hood.
- - - Updated - - -
I really hope so. But aerodynamics are aerodynamics. I am worried a Cd less than 0.2 will lead to unacceptable compromises.�
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