I may be mixed up tho. Here is what Bard explained the both as.
150 = ah
170 = watt-hours per kilogram (Wh/kg)
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To watch for: results of the testing done for EPA cert for CyberTruck
- Thread starter scottf200
- Start date
I may be mixed up tho. Here is what Bard explained the both as.
150 = ah
170 = watt-hours per kilogram (Wh/kg)
AlanSubie4Life
Efficiency Obsessed Member
Yeah this is the calculation. (Nominal voltage * Ah capacity = Wh capacity) And it's probably pretty close. However, in these documents, sometimes it's a bit off. For example, for Model 3 Performance it is 235Ah*360V = 84.6kWh. For the Hummer EV it's WAY off (238kWh; probably due to some pack being locked out). So only "in the ballpark." All the same, in this case it looks likely to be close to correct, and to me it seems ~123kWh is a virtual certainty with what we know now, not 129kWh as I thought (primarily to make the charging efficiency work out well). (Sad)170ah = 138.72 kWh
150ah = 123.00 kWh
Which is going to lead to the following questions:
1) Maybe 42.9kWh/100mi ends up corresponding to Beast version? (42.9kWh/100mi*320mi*0.89 = 122kWh)
2) If not 1, why is the charging efficiency so bad? (84%). Or is the 42.9kWh/100mi number just wrong (too high)?
3) With 123kWh and a range of 320mi/340mi, I'm starting to strongly suspect that those are STREET tire results (sad!). It's just seems too good to be true to get that sort of range with that energy PLUS we have these Beast mode versions wandering around (with AT tires) which show ~293 miles at 100%.
So I'd guess:
293mi Beast AT 20" tires
320mi Beast street tires (18" or 21" or whatever; just street tires with even more aero covers)
340mi Dual motor street tires
Nice 'Battery Specific Energy' comparison in Troy Teslike X/Twitter post.I may be mixed up tho. Here is what Bard explained the both as.
150 = ah
170 = watt-hours per kilogram (Wh/kg)
View attachment 996468
AlanSubie4Life
Efficiency Obsessed Member
Also relevant (also pointed out & linked elsewhere) for this thread, since it is half the info that the EPA tests will have:
Google: "california air resources board executive orders passenger vehicles"
ww2.arb.ca.gov
Cybertruck AWD (429.76 miles):
Cybertruck Beast (418.82 miles):
These give charge-depleting (probably 123kWh or so but TBD!) UDDS results (half of the EPA test - this is the "city" part). In my opinion (it's not known yet) these results are what is obtained with the R/T (A/T) tires on the vehicle. (So these would produce the 318mi/301mi ranges for CT.)
As outlined elsewhere, reasonable to assume about 90%-92% of the UDDS result for Highway result. (Have to wait for EPA result to know for sure.)
Then you do: 0.7*(0.55*UDDS + 0.45*HWYFE) to get the EPA range.
Tesla will scale this up by 0.767/0.7 (roughly) to give the actual EPA range. (When normalizing results this range expansion should be backed out (multiply by 0.7/0.767) since it is not applicable to best-case range results for the most part (it's a valid and legal expansion of EPA rated range (which does not represent range, really), but it represents improved performance relative to a 0.7 scaled result, in sub-optimal conditions, where range will be nowhere near the max rated range).)
Google: "california air resources board executive orders passenger vehicles"
New Vehicle and Engine Certification: Executive Orders for Light-Duty Vehicles | California Air Resources Board
The New Vehicle and Engine Certification Program is responsible for the certification of new engines, vehicles, powertrains, aerodynamic devices and other new certifications. Vehicles and engines may be sold and otherwise produced in California only if approved by Executive Order (EO) after...
ww2.arb.ca.gov
Cybertruck AWD (429.76 miles):
Cybertruck Beast (418.82 miles):
These give charge-depleting (probably 123kWh or so but TBD!) UDDS results (half of the EPA test - this is the "city" part). In my opinion (it's not known yet) these results are what is obtained with the R/T (A/T) tires on the vehicle. (So these would produce the 318mi/301mi ranges for CT.)
As outlined elsewhere, reasonable to assume about 90%-92% of the UDDS result for Highway result. (Have to wait for EPA result to know for sure.)
Then you do: 0.7*(0.55*UDDS + 0.45*HWYFE) to get the EPA range.
Tesla will scale this up by 0.767/0.7 (roughly) to give the actual EPA range. (When normalizing results this range expansion should be backed out (multiply by 0.7/0.767) since it is not applicable to best-case range results for the most part (it's a valid and legal expansion of EPA rated range (which does not represent range, really), but it represents improved performance relative to a 0.7 scaled result, in sub-optimal conditions, where range will be nowhere near the max rated range).)
Mrbrock
Active Member
Without the highway data, you can draw a somewhat inconclusive conclusionAlso relevant (also pointed out & linked elsewhere) for this thread, since it is half the info that the EPA tests will have:
Google: "california air resources board executive orders passenger vehicles"
New Vehicle and Engine Certification: Executive Orders for Light-Duty Vehicles | California Air Resources Board
The New Vehicle and Engine Certification Program is responsible for the certification of new engines, vehicles, powertrains, aerodynamic devices and other new certifications. Vehicles and engines may be sold and otherwise produced in California only if approved by Executive Order (EO) after...
Cybertruck AWD (429.76 miles):
Cybertruck Beast (418.82 miles):
These give charge-depleting (probably 123kWh or so but TBD!) UDDS results (half of the EPA test - this is the "city" part). In my opinion (it's not known yet) these results are what is obtained with the R/T (A/T) tires on the vehicle. (So these would produce the 318mi/301mi ranges for CT.)
As outlined elsewhere, reasonable to assume about 90%-92% of the UDDS result for Highway result. (Have to wait for EPA result to know for sure.)
Then you do: 0.7*(0.55*UDDS + 0.45*HWYFE) to get the EPA range.
Tesla will scale this up by 0.767/0.7 (roughly) to give the actual EPA range. (When normalizing results this range expansion should be backed out (multiply by 0.7/0.767) since it is not applicable to best-case range results for the most part (it's a valid and legal expansion of EPA rated range (which does not represent range, really), but it represents improved performance relative to a 0.7 scaled result, in sub-optimal conditions, where range will be nowhere near the max rated range).)
when comparing the udds from the LR MY 450.93 to the CT 429.76 and get 314 miles. However, the RWD MY is 420.01 miles which would be 307 miles!!! And higher than the Model y AWD 380.82 miles which would translate to 279 miles (spot on). The 2021 MY RWD was 356.82 miles which translates to 260 miles (listed at 244 back then). So makes you Wonder about the RWD MY and what Battery is in there with the 260 mile estimated range from the 420 udds range. Something doesn’t add up.
AlanSubie4Life
Efficiency Obsessed Member
Yeah this one doesn’t add up. But on the other hand they arguably haven’t sold it since it’s not on the EPA website (I don’t pay close attention to MY but I sure this is relatively easy to work through- they can sell a prior version).
For the others, please quote the range normalized to 0.7, not the EPA range. (This is easy to determine, just look up the data.)
It’s hard to make comparisons and assess the estimates accurately otherwise. It would be very confusing!!!
I think it’ll all be within a couple percent. Obviously it is accurate exactly as long as Highway range is 90% or 92%, and this estimate will not always be exactly correct. But if it is, it’s just math.
Mrbrock
Active Member
AlanSubie4Life
Efficiency Obsessed Member
When did I say they weren’t selling the RWD MY??? I most definitely did not say that (see above!).
Like I said, they can sell any of the versions they have previously tested and as long as they state the mileage correctly for what they are selling, all is well.
There is no EPA rating for the Model Y you reference (at least, not yet). When there is, there will be no mystery.
You can also do the math with what we know, and get a really good estimate of the battery size. It’s not magic.
Mrbrock
Active Member
"they arguably haven't sold it since it's not on the EPA website" not quite sure how I am supposed to take that with regards to what is currently for sale. The CARB doc is for the 2023 RWD MY. What they have been selling is the 2023 RWD MY. Based on the CARB doc, the 260 miles EPA estimate is way off base.
AlanSubie4Life
Efficiency Obsessed Member
Yes. This indicates that they are not the same vehicle. (Not surprisingly, as those appellations lack specificity.)
There is no 2023 or 2024 Model Y RWD on the EPA website. I'm not sure what the rules are on low volume vehicles - there have been vehicles in the past which were sold (55.x kWh LFP Pack Model 3 at end of 2021 I think) which never seemed to show up.
A gentle reminder to not solely quote EPA estimates as it is confusing in a conversation like this - be sure to renormalize to 0.7.
On that topic.
I have no idea where you are getting this - this translates to about 240 miles. (You can find the exact value by looking up the actual highway result and plugging into the formula 0.7*(0.55*UDDS + 0.45 * HWFE) . )
And the 2021 MY RWD was the SR+! It got about 303 miles on Highway. This is actually 86% of city, not 90-92%, so it’s going to have a couple percent error using the provided estimating formula.
Actual rating was 244*0.7/0.733 = 233 miles (formula predicted 240). The 0.733 is readily available from public documents as described.
No idea how you did this - this gives using the formula with estimate of 92% highway (not looking up actual value) which result in scalar 0.675:
450.93*0.675 = 304. (Actually is 330 I think, so you can see that this is extremely well aligned if you back out the scalar (once you look it up).)
Similarly, 284 miles. No idea actual rating.
Don't assume the 0.767 for all vehicles - that's just an estimate for CT since we don't know it yet. It's different for different vehicles. That's why it is best to use 0.7!
Anyway overall I am not sure you looked at all the numbers above. Go ahead and make a spreadsheet - it makes it easier to get it all to align because you're not just writing numbers down everywhere and it does all the calculations for you. This entire message and the last several of mine have been totally incomprehensible for this reason (because of the lack of the spreadsheet, specifically).
You'll find it all aligns very closely. Not really much guessing involved.
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Mrbrock
Active Member
Ok, your formulas are above my level of knowledge right now (and are likely covered way more in depth in other posts and frums )so I am just using the UDDS rating for the LR AWD compared to its EPA rating and then using that ratio with the UDDS rating of the RWD MY from 2021. That spits out 260 which is what the current RWD MY is estimated to be, not 244. If you use the same LR AWD ratio with the 2023 RWD MY you get over 300 miles.
AlanSubie4Life
Efficiency Obsessed Member
See above modified post.
It’s really not complicated at all, though this conversation and my messages make it seem so.
Just look up city and highway raw results for each vehicle, plug into the formula. These are in public domain (dis.epa.gov for DC; epa datafile for AC only). You can get the scalar from the epa data file (divide adjusted by unadjusted), or just take the formula output and divide EPA stated range by formula output. These two methods should yield the same result for scalar (which we really don’t care about but it connects the UDDS/HWY results to the fuel economy label).
You don’t need to do any estimating if you have both HWY and UDDS numbers. So you can do an estimate for the CT as above, and an estimate for this mysterious MY (you might want to use an estimate formula using a city/highway scaling tailored to the Model Y rather than a generic).
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AlanSubie4Life
Efficiency Obsessed Member
There is a discrepancy between CARB and EPA on the 2023 MY LR AWD. (It's 450 in the carb and 446 in the EPA). Not a big deal but worth noting.Without the highway data, you can draw a somewhat inconclusive conclusion
There's a 2023 MY RWD Submission to EPA giving 353 miles UDDS and 322 HWFE. So that's presumably what they're selling. Doesn't show up on fueleconomy.gov AFAIK.
No idea what the 420-mile RWD submission to CARB is, but it's obviously a different car. And it's probably not being sold yet.
It would have about 312 miles of range, very roughly.
Anyway, quick summary (it's not the same formulas all the way down each column, I deliberated hacked some stuff). I'm not going to bother explaining it. But it's pretty straightforward and shows the method. All lines up within a couple percent as expected. Cybertruck included to keep this on topic and show how it works.
Anyone can do this. It's not complicated math. The biggest issue is getting the datapoints. Formulas above.
Focus on the 0.7 values, ignore the EPA values. EPA values are just confusing.
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