Model 3 Performance - charged to 100% shows 293 miles range. Why?

[AlanSubie4Life]

Someone mentioned in another thread that the actual "rated" number on the energy graph has changed and is now slightly higher. maybe they adjusted the rated usage for the p3d in the recent update and now it shows a more realistic estimate

I did not see that. Someone with this behavior should attach a picture of that Energy diagram showing the three numbers with three significant figures each:
1) Battery gauge remaining miles
2) Recent efficiency
3) Projected Range

Similar to what was done here, but for one of the P3D Stealths or AWD with this drop in range:

Mid Range Battery Math

Normally we would expect a charging constant of 245Wh/rmi. Maybe it has changed to 259Wh/rmi?

 

[rtshefe]

I may be confused on what you asked me to post..but from looking at this graph, in my recent drive I got extemely close to the "rated" line and that was at 272wh/mi. seems much higher than the 245wh/mi

am I looking at the wrong thing?

suddenly after the update it seems like im much closer to the rated number

this is on a 2020 p3d+ currently at 599mi

 

[diamond.g]

I may be confused on what you asked me to post..but from looking at this graph, in my recent drive I got extemely close to the "rated" line and that was at 272wh/mi. seems much higher than the 245wh/mi

am I looking at the wrong thing?

suddenly after the update it seems like im much closer to the rated number

this is on a 2020 p3d+ currently at 599mi

View attachment 494754

Out of curiosity, if you tell the car you have different tires, does the rated line move?
I suspect Tesla may be showing EPA values for the P's in alignment with the tire size.

 

[AlanSubie4Life]

I may be confused on what you asked me to post..but from looking at this graph, in my recent drive I got extemely close to the "rated" line and that was at 272wh/mi. seems much higher than the 245wh/mi

am I looking at the wrong thing?

suddenly after the update it seems like im much closer to the rated number

this is on a 2020 p3d+ currently at 599mi

View attachment 494754

You need to switch to miles for this picture otherwise it is hard to interpret anything.

However, if you were at 193rmi (67% of 293) in that picture, then the new constant looks like:

272Wh/mi*191mi / (0.67* 293rmi) = 265Wh/rmi

That would be really high. We definitely need a picture with your rated miles instead of %. I highly doubt you have 293 miles at 100%.

 

[AlanSubie4Life]

Out of curiosity, if you tell the car you have different tires, does the rated line move?
I suspect Tesla may be showing EPA values for the P's in alignment with the tire size.

Was wondering the same thing - in the past it has not made a difference, but given the 2020 different EPA ratings for different tires, they may be in the midst of implementing that.

293 rated miles would be consistent with a Dual Motor with 19” wheels which will soon receive a range boost to 304 rated miles. (304/322*310 = 293)

You’d expect the 3P+ to be at 299/322*310 = 288rmi.

And regular AWD/Stealth with 18” selected would be at:
310/322*310 = 298rmi

With corresponding changes in the constants to maintain equal energy.

In the future they potentially will roll an update scaling up all the above miles by the ratio:
322/310, while scaling down the rated line and constants by the ratio 310/322.

Would result in rated miles (assuming a 100% capacity battery) of:
18” 322rmi
19” 304rmi
20” 299rmi

As per the EPA numbers. We’ll see.

To start with it would be good to get those Energy Screen pictures - with rated miles, not %, showing. Along with details of the exact car configuration and wheel configuration currently selected for your car. Does the OP here have a 3P+ or a 3P Stealth (and which wheels)?

————— Part 2....

Perusing plot above, it does seem likely that the constant has changed. Assuming 293rmi for 100% in the picture above, the numbers don’t align with my list above (they are off by the ratio 293/288 for the 3P+), but it is close...

One explanation would be that they have made more energy available from the battery for part of this upcoming (2020 only?) range increase. That would explain it.

For the 3P+, assuming the above picture does represent a vehicle with 196 rated miles remaining (67% of 293rmi), it looks like we now have:

265Wh/rmi * 293rmi = 77.6kWh. (Compare to prior 76kWh number (310rmi * 245Wh/rmi).

So if that’s the case, then we’d expect an efficiency improvement with an upcoming software update of only 299/293 = 1.02 or 2%.

And with an imminent update we might see that charging constant (5Wh/mi less than the rated line) drop to 293/299*265Wh/rmi = 260Wh/rmi for 3P+.

For the other vehicles we would be looking at:

20” 3P+: Eventually 260Wh/rmi, should show 293rmi at 100% currently with charging constant 265Wh/rmi.
19” 3D: Eventually 255Wh/rmi, but should show 298rmi at 100% currently with charging constant currently 260Wh/rmi
18” 3D/3P: Eventually 241Wh/rmi, should show 317rmi at 100% currently with unchanged constant of 245Wh/rmi


This could all be a bunch of nonsense. We need data of course.

 

[rtshefe]

here is a pic with the miles
(tesla mobile came and installed homelink in my garage between the pic I took earlier and this one now..so thats why it has a homelink icon now)

 

[rtshefe]

ok, so I just changed the wheel setting to 19" and the range estimate jumped to 199, then I changed to the aero 18" and the estimate jumped to 207

(the rated line does move with the change in wheels)

 

[AlanSubie4Life]

here is a pic with the miles
(tesla mobile came and installed homelink in my garage between the pic I took earlier and this one now..so thats why it has a homelink icon now)
View attachment 494783

This confirms your constant is 265Wh/rmi. This is a huge increase in the constant - it used to be 245Wh/rmi.

It looks like your range has actually increased. Your 100% charge is 293rmi.

This means you have 77.6kWh available. This is higher than your prior amount, which was 245Wh/rmi*310rmi=76kWh.

It looks to me like Tesla is prepping for their efficiency improvement rollout.

EDIT:
I saw your edits! Thanks for that info.
18” constant: 248Wh/rmi
19” constant: 258Wh/rmi

Does not quite align with predictions above but not too far off.

Try extrapolating your range to 100% with the 18” wheel setting...seems like it will be over 310 - as predicted, more range! (Modifying my guess to 313 rated miles at 100% rather than 317 rated miles). And the upcoming efficiency improvement will be something like 3% for the 18”, not just 2%.

Really, your pictures are super, super helpful. Really good to capture this middle step. Thanks.

 

[rtshefe]

I also drove around the block after homelink was installed..so the battery is technically at 66% and showing 194mi for range...not that it changes very much in your calculations

 

[AlanSubie4Life]

I also drove around the block after homelink was installed..so the battery is technically at 66% and showing 194mi for range...not that it changes very much in your calculations

In fact I did not take that % into account and noted that it seemed that your % was lower. That is the value of using rated miles for this stuff. Note that 194/0.66 = 294. And 207/0.66 = 314.

Your range has been increased. It’s actually increased to 317 rated miles under the old system with the 245Wh/rmi constant. But because they increased the constant it only looks like 3-4 miles more. It is possible there is more to come (though the efficiency improvements may already be there and they just have not modified the constant - though that would be weird).

The important thing is the available energy which seems to have increased to 77.6kWh or so. Of course, it is possible your trip meter will start to read higher now too and this is just an adjustment in their scaling of kWh (they always seemed to be “large” kWh before!), with no actual impact on real-world range or energy. All we can do is track the numbers, though.

Corrected a typo in one of my posts above (wrote 260Wh/rmi rather than 245Wh/rmi)...

 

[Msjulie]

I don't have over-time usage numbers but my car at 82% shows a range of 236. If I were believe the originally advertised range of 310 my car is showing range of a car at 76% SOC ie in theory I should be showing a range of ~254 at this SOC

It feels like more range loss than it should but Tesla claims not. I have seen others with lower range but it 'feels' like most people showing greater range for similarly aged car; my car has < 21k miles and has a July 2018 build date.

I need to keep better records from the energy use app I guess.

 

[tomas]

Something funky going on. I suspect it may be that they put wheel size in as a variable and set everyone to 20. I’ll be in CA end of week with my 3P with 18s and I’ll test that theory.

I blame apple for starting this crap where behaviors change significantly but there’s no customer communication. I blame Tesla for following that bad example. Absent documentation, we are left to assume it is an error or something more nefarious.

 

[SigNC]

whpm of perf is higher. I doubt you'll ever see 310 extrapolated, I know i never did.

 

[AlanSubie4Life]

It is because your BMS system thinks you have 293rmi*245Wh/rmi = 71.8kWh available for use, rather than the 310rmi*245Wh/rmi = 76kWh available on a typical new vehicle.
.

So @LakeForestM3, wanted to circle back on this, knowing this new information. The above is incorrect. I did not know that the underlying constants had changed (such events are very rare, and the addition of wheel options changing the constants is a new thing - though very understandable).

Previously: 310rmi*245Wh/rmi = 76kWh

Now: 293rmi*265Wh/rmi = ~77.6kWh

This means that nominally, you now have MORE energy available than you had before (assuming each “kWh” has the same energy content...which is very hard to determine). So this 293 rated mile drop is actually an INCREASE in range for you!

As far as I know this only applies to 2020 Model 3s - have not seen anything like this on my 2018.

And by the way, if you have a 2020 3P+, it is actually rated for 299 miles, not 310. You can see this on the window sticker. I think you may see a bump up to 299 in the coming weeks, but that is just a guess - I don’t know.

I will update my Lines and constants tracking post at some point soon.

Knowing what these constants are is key to understanding what that battery gauge shows - the number by itself is not extremely useful except as a relative measure - and not even that if the constants change. And they can always be derived as above from a picture of the Energy Consumption screen:

Charge Const = Recent Efficiency * Projected Range / Battery Gauge Displayed Miles

All numbers should have three digits for accuracy so should be done at a relatively high state of charge. (Greater than 70% or so.)

 

[henchman24]

I'll have to check this out for my 3P+. I've been in winter mode with 18s and have not noticed a range decrease (been extrapolating at 307-309 since the day I bought the car), but it would make sense that they are adjusting based on wheel size now since the cars are rated differently.

 

[Chris3g]

Another data point, my 2020 P- w/ 19” wheels which was affected by the .50 update seems to be using a constant of 258Wh now.

I also checked the other wheel configs and 20” is 265Wh, 18 Aero is 248 Wh.

 

[AlanSubie4Life]

I'll have to check this out for my 3P+. I've been in winter mode with 18s and have not noticed a range decrease (been extrapolating at 307-309 since the day I bought the car), but it would make sense that they are adjusting based on wheel size now since the cars are rated differently.

I don’t know, but it is quite possible these software changes will only apply to the 2020 vehicles (though sounds like you may have one). Doesn’t really make sense but Tesla may decide to do that depending on what they think will cause the fewest headaches.

 

[ChemEJon]

Another data point, my 2020 P- w/ 19” wheels which was affected by the .50 update seems to be using a constant of 258Wh now.

I also checked the other wheel configs and 20” is 265Wh, 18 Aero is 248 Wh.

20" should be 270 Wh/mi my photo shows my avg at 268 Wh/mi and its right below the rated range line.

 

[AlanSubie4Life]

20" should be 270 Wh/mi my photo shows my avg at 268 Wh/mi and its right below the rated range line.

That’s correct; the rated range LINE is always 5Wh/mi higher than the actual constant used for the calculations on that screen. So the charging constant with 20” wheels at least on 2020 vehicles is 270Wh/mi (Line position) - 5Wh/mi (offset) = 265Wh/mi (charging constant) as determined above.

 

[henchman24]

I don’t know, but it is quite possible these software changes will only apply to the 2020 vehicles (though sounds like you may have one). Doesn’t really make sense but Tesla may decide to do that depending on what they think will cause the fewest headaches.

2018 over here... I'll swap the wheel settings around and post my findings.