[Spoiler Alert + Mild Speculation] Tesla has created a monster!

[omgwtfbyobbq]

Oh.... I wonder if Tesla's using a limited slip differential with the 3. That could account for "both" under axle regen, and still be RWD. Someone from reddit mentioned it could help with uneven tire wear too, which I guess is an issue that the Model S can have.

 

[KarenRei]

Graphs, graphs, graphs

Two of the PHEVs in the above graph have higher actual acceleration than their theoretical max electric acceleration because they also use a gasoline engine in parallel. I presume the X100D figure to be erroneous. In general the achieved 0-60 times are always going to be significantly lower than theoretical because of current and torque limits.

Above is calculated from recharge event energy (highway) / charge-depleting range (highway). Note that charge-depleting mile figures are higher than EPA range miles.

And, a revised version of my last one to have a little less clutter:

I'd like to do the same comparison (where appropriate) for gas vehicles vs. the Model 3, but for that one I'd like to do my best to standardize features before comparing price, rather than just comparing MSRPs. Does anyone have a good list of standard features and pricing between M3 and gasoline competitors in its class? I think someone posted one somewhere...

 

[JeffK]

Graphs, graphs, graphs

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And, a revised version of my last one to have a little less clutter:
View attachment 240287

I'd like to do the same comparison (where appropriate) for gas vehicles vs. the Model 3, but for that one I'd like to do my best to standardize features before comparing price, rather than just comparing MSRPs. Does anyone have a good list of standard features and pricing between M3 and gasoline competitors in its class? I think someone posted one somewhere...

I'd definitely like to see one for MSRP vs 0-60 times including ICEs under 5.1 seconds.

 

[03DSG]

Excellent idea. Let us know how it goes.

I asked him yesterday. He must be busy as he hasn't replied yet..........

@elonmusk Model 3 AC 3 Phase Permanent Magnet motor???

 

[Thomas Edison]

Oh.... I wonder if Tesla's using a limited slip differential with the 3. That could account for "both" under axle regen, and still be RWD. Someone from reddit mentioned it could help with uneven tire wear too, which I guess is an issue that the Model S can have.

They won't use a LSD on the model 3. With modern traction control it's a waste on an electric car. Also adds weight and is not as strong, more parts and so on.

 

[JeffK]

They won't use a LSD on the model 3. With modern traction control it's a waste on an electric car. Also adds weight and is not as strong, more parts and so on.

LSD would really make it feel like a spaceship...

 

[Pajda]

You are right, missed the zero.
Here is the "right" math.

Assuming that you have 4416 cells and an 80.5kWh pack: 80500/4416/3.6v = 5064 mAh per cell or 18.2 Wh

Interestingly if you assume that number for the standard range Model 3, with a 2944 cell pack will have a 53.6kWh pack.

-Jim

The nominal voltage of battery is 350 V (96s = the same as in Model S/X) and this gives 3.65 V nominal cell voltage. So the nominal cell capacity is then equal to 5000 mAh.

 

[Model 3]

They won't use a LSD on the model 3.

Good, I was starting to get nervous for a Model 3 running on LSD and FSD at the same time

 

[powertoold]

Considering all of the information thus far, how fast (mi/hr) would a standard Range model 3 charge with a 120 volt Nema 5-15?

 

[transpondster]

The nominal voltage of battery is 350 V (96s = the same as in Model S/X) and this gives 3.65 V nominal cell voltage. So the nominal cell capacity is then equal to 5000 mAh.

or more easily just divide stated energy capacity 230 Ah by 46, off course 230 * 350 / 3,65 * 96 * 46 sounds cooler

 

[kingjamez]

or more easily just divide stated energy capacity 230 Ah by 46, off course 230 * 350 / 3,65 * 96 * 46 sounds cooler

No, because the stated energy capacity is the useable energy, not the actual capacity.

 

[KarenRei]

Ed: Just noticed, the label on the left of "Curb weight vs. charge depleting range" is wrong - that should be highway charge depleting range, not EPA range.

 

[KarenRei]

Aha! I think I've figured out this whole "EPA range" vs. "Highway range" thing!

https://www.fueleconomy.gov/feg/pdfs/EPA test procedure for EVs-PHEVs-7-5-2012.pdf

Basically, the drive cycle they use doesn't represent typical real-world ranges that consumers will actually achieve, and the EPA knows that. So manufacturers are given a few options. (ED: See stopcrazypp's update below) The most common one is to take the drivecycle results (the "charge depletion range") and multiply it by 0.7. Meaning that the charge depletion range in this case would be nearly 1.43x that of the EPA sticker range. Lo and behold, that's where the majority of our ranges slot in (see the graph "Charge depletion range vs. EPA range"). Another option is for them to use a special vehicle-specific five-cycle method, which may explain why some of the other figures are further away from that 1.43x figure. I still suspect, however, that the Volt and Model X P100D are anomalies.

If we go with that, then the sticker range for the Model 3 LR should be 318 miles. A further implication would be that wall-to-wheels on the Model 3 LR would be 281 Wh/mi and pack-to-wheels would be 245 Wh/mi. Wall to wheels comes from the pack recharge energy divided by the number of miles, scaled by the 0.7 adjustment factor; and pack to wheels comes from the wall to wheels figure adjusted by the recharge efficiency of 87%. The efficiency in turn comes from the average voltage during the cycle times the integrated amp hours during the cycle, divided by the recharge energy.

Model 3 SR will be somewhat lower Wh/mi due to its lower mass (probably ~3% ish). Also, the dual motor versions will reduce Wh/mi as well (Model S sees about a 5% reduction in energy consumption with dual motors, probably 3-4% here). Interesting question whether they're testing with PUP or not - since you're supposed to test base models without options, but AFAIK Tesla doesn't have any base models yet. PUP shouldn't have a big effect on range, but it will add a bit more weight and possibly a tiny bit of cross section - maybe 1%. These figures will be done with aero wheels; "baller" wheels will increase your energy consumption / reduce range 2-3%.

So, your most efficient Model 3 (dual-motor non-PUP aero-wheel, short range) will probably come in at around 260Wh/mi wall to wheels and 225Wh/mi pack to wheels. Your least efficient (long range, RWD, PUP, baller wheels) will come in at around 288Wh/mi wall to wheels, 251Wh/mi pack to wheels.

 

[stopcrazypp]

Aha! I think I've figured out this whole "EPA range" vs. "Highway range" thing!

https://www.fueleconomy.gov/feg/pdfs/EPA test procedure for EVs-PHEVs-7-5-2012.pdf

Basically, the drive cycle they use doesn't represent typical real-world ranges that consumers will actually achieve, and the EPA knows that. So manufacturers are given a few options. The most common one is to take the drivecycle results (the "charge depletion range") and multiply it by 0.7. Meaning that the charge depletion range in this case would be nearly 1.43x that of the EPA sticker range. Lo and behold, that's where the majority of our ranges slot in (see the graph "Charge depletion range vs. EPA range"). Another option is for them to use a special vehicle-specific five-cycle method, which may explain why some of the other figures are further away from that 1.43x figure. I still suspect, however, that the Volt and Model X P100D are anomalies.

If we go with that, then the sticker range for the Model 3 LR should be 318 miles. A further implication would be that wall-to-wheels on the Model 3 LR would be 281 Wh/mi and pack-to-wheels would be 245 Wh/mi. Wall to wheels comes from the pack recharge energy divided by the number of miles, scaled by the 0.7 adjustment factor; and pack to wheels comes from the wall to wheels figure adjusted by the recharge efficiency of 87%. The efficiency in turn comes from the average voltage during the cycle times the integrated amp hours during the cycle, divided by the recharge energy.

Model 3 SR will be somewhat lower Wh/mi due to its lower mass (probably ~3% ish). Also, the dual motor versions will reduce Wh/mi as well (Model S sees about a 5% reduction in energy consumption with dual motors, probably 3-4% here). Interesting question whether they're testing with PUP or not - since you're supposed to test base models without options, but AFAIK Tesla doesn't have any base models yet. PUP shouldn't have a big effect on range, but it will add a bit more weight and possibly a tiny bit of cross section.

Note: starting in 2012, all manufacturers are required to use the actual 5-cycle test results. They are no longer allowed to use the ~0.7 formula (other than perhaps some models that may have carried over unchanged or was just tested in the same year). That formula was only intended for the transitional phase.
http://www.caranddriver.com/feature...y-mpg-estimates-measuring-fuel-economy-page-2

 

[KarenRei]

Note: starting in 2012, all manufacturers are required to use the actual 5-cycle test results. They are no longer allowed to use the ~0.7 formula (other than perhaps some models that may have carried over unchanged).
http://www.caranddriver.com/feature...y-mpg-estimates-measuring-fuel-economy-page-2

Thanks for the update. Any clue how closely the five-cycle tracks to the old 0.7x correction factor?

 

[stopcrazypp]

Thanks for the update. Any clue how closely the five-cycle tracks to the old 0.7x correction factor?

It's still useful for a rough approximation (after all, that was how EPA designed it to be), but just don't expect to get the exact numbers to match up.

 

[KarenRei]

Strange that the certification document would include the old depletion cycle and not the five cycle data, though....

 

[R.S]

Strange that the certification document would include the old depletion cycle and not the five cycle data, though....

It's still used for ZEV compliancy tests.

 

[omgwtfbyobbq]

Strange that the certification document would include the old depletion cycle and not the five cycle data, though....

I believe the FTP/HFET are still the only two tests required, and the EPA uses the results of those two tests possibly plus some vehicle-specific data, to derive the results for the other three tests.

The second method, the derived 5-cycle method, determines fuel economy and CO2 emissions values from the FTP and HFET tests using equations that are derived from vehicle-specific 5-cycle model typedata, as determined in paragraph (a)(2) of this section.

40 CFR 600.210-12 - Calculation of fuel economy and CO 2 emission values for labeling.

 

[stopcrazypp]

I believe the FTP/HFET are still the only two tests required, and the EPA uses the results of those two tests possibly plus some vehicle-specific data, to derive the results for the other three tests.



40 CFR 600.210-12 - Calculation of fuel economy and CO 2 emission values for labeling.

Actually this section says that alt fuel and dual alt fuel vehicles are exempt from the 5-cycle requirement. It seems it only applies to ICE cars:
"§ 600.115-11 Criteria for determining the fuel economy label calculation method.
This section provides the criteria to determine if the derived 5-cycle method for determining fuel economy label values, as specified in § 600.210-08(a)(2) or (b)(2) or § 600.210-12(a)(2) or (b)(2), as applicable, may be used to determine label values. Separate criteria apply to city and highway fuel economy for each test group. The provisions of this section are optional. If this option is not chosen, or if the criteria provided in this section are not met, fuel economy label values must be determined according to the vehicle-specific 5-cycle method specified in § 600.210-08(a)(1) or (b)(1) or § 600.210-12(a)(1) or (b)(1), as applicable. However, dedicated alternative-fuel vehicles, dual fuel vehicles when operating on the alternative fuel, plug-in hybrid electric vehicles while operating in charge-depleting mode, MDPVs, and vehicles imported by Independent Commercial Importers may use the derived 5-cycle method for determining fuel economy label values whether or not the criteria provided in this section are met. Manufacturers may alternatively account for this effect by multiplying 2-cycle fuel economy values by 0.7 and dividing 2-cycle CO2 emission values by 0.7."
40 CFR 600.115-11 - Criteria for determining the fuel economy label calculation method.

I didn't realize that (C&D article didn't point it out).

This part also mentions the 0.7 method.

So there are three methods:
1) True 5-cycle (required for ICE, apparently not for others)
2) Derived 5-cycle
3) Multiply 2-cycle by 0.7