Model 3 220Wh/mile vs P85 299Wh/mile on same 50 mlie trip

[Dr. J]

My driving model for the Model 3 LR predicts 223 Wh/mi at a steady 65 mph (this is approximate and hasn't been validated with empirical data). If I add 1500 lbs in payload, that increases to 247 Wh/mi, only an 11% increase.

What does your model predict for the Model 3 SR? TIA.

 

[Cloxxki]

If you look at the range/consumption difference between P and non-P cars, it's clear how wasteful the P, in the super mellow EPA cycle as well as real-life. No doubt the 3 still smashes the non-P S for above mentioned reasons, though.

 

[bkp_duke]

As has been stated above, weight plays a role in stop-and-go traffic and city driving, but it doesn't play a very significant role in steady-state cruising on the highway.

BS. I did an 8500 mile, 90% interstate driving road trip this pas summer in a 2013 P85 and RARELY got below 300 wh/mi.

It's not just wind resistance that plays a big role, it's rolling resistance on the tires. I have 21" turbines and they have a pretty big impact on rolling resistance compared to the Model 3's 18 or 19". Weight has a large impact upon rolling resistance (i.e. the harder you press down on the rubber, the higher the rolling resistance).

Does anyone know if the Model 3 tires are sport tires or "low rolling resistance" tires.

 

[ForeverFree]

Michelin Primacy (LRR, all-season)

 

[smartypnz]

Not many miles yet but average was 256 Wh/mile before I took it out for fun this morning. After humiliating a few ICE's and a BMW i3 that couldn't handle the curves. And then over a hill with 8-10 % grade almost 1300 elev with 3.5 miles.

So, that 42 miles added onto total gives an avg of 251 Wh/mi. Just amazing - the MS is around 312 after almost 5 years. And battery level says it only used 40 miles

 

[thegruf]

I have always reckoned 1" tyre width costs about 3 mpg in "old money"v in average use, ie about 10%
Also remember Cd is coefficient not absolute value. The M3 has a smaller frontal area so even if it had identical Cd as MS it would still offer less air resistance.
Add more efficient motors and to a lesser extent for cruising lower weight and it is quite logical to see how such figures are readily achieveable.

I can see drivers with a timid right foot (that counts me out) reporting <200WH/mi before long.

All very impressive nonetheless.

 

[T34ME]

Michelin Primacy (LRR, all-season)

That's only for the 18" wheel. 19" Sportwheels have Continental performance tires.

 

[SSedan]

What width? Also within a model tires do change based on size and load requirements so I would not go jumping to the conclusion a Primacy is a Primacy is a Primacy, sort of like people do with the rim size. People talk like rim diameter is THE factor in range reduction from 19-21" wheels on the MS, but it really isn't the rim diameter that matters, tire/wheel combined weight, rubber/tread compounds in the tire etc. are the real culprits.

 

[DR61]

What width? Also within a model tires do change based on size and load requirements so I would not go jumping to the conclusion a Primacy is a Primacy is a Primacy, sort of like people do with the rim size. People talk like rim diameter is THE factor in range reduction from 19-21" wheels on the MS, but it really isn't the rim diameter that matters, tire/wheel combined weight, rubber/tread compounds in the tire etc. are the real culprits.

18": Michelin Primacy MXM4, 235/45-18, 98W

19": Continental ProContact RX, 235/40-19, 96W

 

[Nosken]

18": Michelin Primacy MXM4, 235/45-18, 98W

19": Continental ProContact RX, 235/40-19, 96W

Width measurement is the same-235

FYI--The circumference difference is just like the Model S & X 0.25" difference=negligible

Tire Size Calculator | About Tire Size Conversion | Discount Tire Direct

 

[SSedan]

So at TireRack I looked up the 245 18" Primacy for the
MS
tread depth10/32" weight 27 lbs. rim width 7.5-9" measured rim 8" section width 9.6" tread width8.4" height27.7" revs per mile751


M3 23518" Primacy
tread depth8/32" weight 25 lbs. rim width 7.5-9" measured rim 8" section width9.3" tread width7.8" height26.3" revs per mile790
M3 19" Continental
10/32" 26 lbs. 8-9.5" 8.5" 9.5" 9" 26.4" 787


10mm (.39inch)"size" difference is .6" difference in actual tread width when comparing the MS 245 to the M3 235 18" tire.

Calculators will get you close but not quite there. I agree though height is not a big deal, width likely means more, it is actual friction on the road.

 

[Zoomit]

What does your model predict for the Model 3 SR? TIA.

Assuming the same wheels/tires, the only meaningful difference between the LR and SR, with respect to efficiency, is the reduced weight of the SR. I'm seeing that the SR is 265 lbs lighter, which makes it about 2% more efficient than the LR.

BS. I did an 8500 mile, 90% interstate driving road trip this pas summer in a 2013 P85 and RARELY got below 300 wh/mi.

It's not just wind resistance that plays a big role, it's rolling resistance on the tires. I have 21" turbines and they have a pretty big impact on rolling resistance compared to the Model 3's 18 or 19". Weight has a large impact upon rolling resistance (i.e. the harder you press down on the rubber, the higher the rolling resistance).

Does anyone know if the Model 3 tires are sport tires or "low rolling resistance" tires.

I appreciate your emotion, but the 21" Turbine wheels have very minor effect on rolling resistance. The TIRES you have on your 21" wheels do make a large difference. Also, the 21" wheels have worse AERO than smaller wheels. It's the sticky tires and big spokes cause the reduced range over the smaller wheels at constant speeds. In stop-and-go traffic, the increased inertia of the larger wheels also increases consumption when compared to smaller wheels.

Incidentally, adding 1500 lbs of cargo to the Model S, with non-LRR tires, looks to increase energy consumption at 65 mph from 304 to 339 Wh/mi, a 12% increase. With LRR tires, the consumption increase due to 1500 lbs cargo is from 278 to 305 Wh/mi, a 10% increase.

Don't pay too much attention to the specific numbers here, as I haven't tried hard to refine my Model S energy consumption model. The trends are accurate however. BTW, I'm assuming a Crr of 0.009 for the non-LRR tires and a Crr of 0.007 for the LRR tires.

 

[bkp_duke]

Assuming the same wheels/tires, the only meaningful difference between the LR and SR, with respect to efficiency, is the reduced weight of the SR. I'm seeing that the SR is 265 lbs lighter, which makes it about 2% more efficient than the LR.

I appreciate your emotion, but the 21" Turbine wheels have very minor effect on rolling resistance. The TIRES you have on your 21" wheels do make a large difference. Also, the 21" wheels have worse AERO than smaller wheels. It's the sticky tires and big spokes cause the reduced range over the smaller wheels at constant speeds. In stop-and-go traffic, the increased inertia of the larger wheels also increases consumption when compared to smaller wheels.

Incidentally, adding 1500 lbs of cargo to the Model S, with non-LRR tires, looks to increase energy consumption at 65 mph from 304 to 339 Wh/mi, a 12% increase. With LRR tires, the consumption increase due to 1500 lbs cargo is from 278 to 305 Wh/mi, a 10% increase.

Don't pay too much attention to the specific numbers here, as I haven't tried hard to refine my Model S energy consumption model. The trends are accurate however. BTW, I'm assuming a Crr of 0.009 for the non-LRR tires and a Crr of 0.007 for the LRR tires.

I had 1500lbs of server gear in my car this past summer for this 8500 mile road trip. It caused lot more than a 12% loss. Was more like 20%.