How many wh are in one rated mile?

[Candleflame]

I wonder for the AWD / Performance.

The car computer isnt particularly accurate but I think it uses 149wh/km (239.792wh/km) or maybe 151wh/km, however, driving at this consumption doesnt actually use 1 rated km / km.

Teslafi seems to use 139.8wh/km (224.98wh/mile)

A much quoted figure here is 142wh/km (228.527wh/mile).

Teslabjorns car displayed 485km (just about) while displaying a nominal full charge of 73.7kwh (70.3835kwh without buffer) which would indicate 145wh/km (0.234wh/mile).

 

[holmgang]

about 75000wh usable capacity with 2020 performance rated range of approx 300mi makes 250wh/mi. about as accurate as an estimate can be. that makes about 155wh/km, against my lifetime consumption of 190-195 or so.

ultimately that pegs my actual theoretical range at 385km, and since i use the percentage display, means i ballpark 3-4km per remaining percentage.

 

[Candleflame]

about 75000wh usable capacity with 2020 performance rated range of approx 300mi makes 250wh/mi. about as accurate as an estimate can be. that makes about 155wh/km, against my lifetime consumption of 190-195 or so.

ultimately that pegs my actual theoretical range at 385km, and since i use the percentage display, means i ballpark 3-4km per remaining percentage.

That is not how it works and the car actually starts off with slightly less than 79kwh minus the buffer not 75 kwh actually anyway (The 3 would have been sold as a 75 according to old nomenclatu This topic is not about the range you get from the battery but how much energy equivalence the car attributes to each kwh which is a different way to look at total kwh capacity of the battery.

The rated km has no real relationship to the actual km you can get out of the car but is just a different way of measuring energy, hence some people have called for abolishing rated range and changing it to kwh remaining.

Even if you drive at 150wh/km and get 500km out (so exactly 75kwh) you have actually used more energy as the driving computer does not take into account losses like resistors, heat and certain auxillary power items afaik.


edit: also % is very unreliable as the conversion from rated km/mile to % is variable and only reflective of rated km at 100% charge unless you are at 0% degradation (and new cars likely start off with i.e. -0% to -2% degradation) What I mean by that is that it is not a linear relationshop due to degradation and maybe also some aspects of the buffer getting for some reason removed the closer you get to 0.

I.e. if you have 10% degradation and get 450km out of 100% rather than 498.9km when the car is new the car will actually move closer to 498.9km the closer you get to 0% i.e. at 10% SOC it will still show 50km even though it should show 45km.

 

[holmgang]

That is not how it works and the car actually starts off with slightly less than 79kwh minus the buffer not 75 kwh actually anyway (The 3 would have been sold as a 75 according to old nomenclatu This topic is not about the range you get from the battery but how much energy equivalence the car attributes to each kwh which is a different way to look at total kwh capacity of the battery.

The rated km has no real relationship to the actual km you can get out of the car but is just a different way of measuring energy, hence some people have called for abolishing rated range and changing it to kwh remaining.

Even if you drive at 150wh/km and get 500km out (so exactly 75kwh) you have actually used more energy as the driving computer does not take into account losses like resistors, heat and certain auxillary power items afaik.


edit: also % is very unreliable as the conversion from rated km/mile to % is variable and only reflective of rated km at 100% charge unless you are at 0% degradation (and new cars likely start off with i.e. -0% to -2% degradation) What I mean by that is that it is not a linear relationshop due to degradation and maybe also some aspects of the buffer getting for some reason removed the closer you get to 0.

I.e. if you have 10% degradation and get 450km out of 100% rather than 498.9km when the car is new the car will actually move closer to 498.9km the closer you get to 0% i.e. at 10% SOC it will still show 50km even though it should show 45km.

All of this is really just academic anyway, especially if the point is to figure out what the computer uses to project its standard range - what it displays when battery is full i.e. your "rated" mile.

In fact, we shouldn't need to derive it backwards. It's the solid line in the energy graph labeled "rated"(whereas the wiggly line is historical instantaneous consumption and dashed line is averaged consumption over fixed distance).

About resistive losses, auxiliary consumption, that should all be taken into by the trip computer, hence what I use as my actual rate (190-195) comes from there, and what projects as my theoretical range based on my actual conditions.

This is the number matters to me when planning for drives. Same as the distance/% value. If I'm at 30% and the SC is 50km away, I know I'll get there with 15% left. Of course, i can expand the navigation card to show that Remaining % number, or turn on the Trip tab of the energy graph, or simply switch battery display from % to distance....it's all simple arithmetic anyway.

But I prefer battery status on %, and I can just monitor the nav KM remaining and determine whether I can drive a bit more aggressively or if I need to be conservative.

 

[Candleflame]

All of this is really just academic anyway, especially if the point is to figure out what the computer uses to project its standard range - what it displays when battery is full i.e. your "rated" mile.

In fact, we shouldn't need to derive it backwards. It's the solid line in the energy graph labeled "rated"(whereas the wiggly line is historical instantaneous consumption and dashed line is averaged consumption over fixed distance).

About resistive losses, auxiliary consumption, that should all be taken into by the trip computer, hence what I use as my actual rate (190-195) comes from there, and what projects as my theoretical range based on my actual conditions.

This is the number matters to me when planning for drives. Same as the distance/% value. If I'm at 30% and the SC is 50km away, I know I'll get there with 15% left. Of course, i can expand the navigation card to show that Remaining % number, or turn on the Trip tab of the energy graph, or simply switch battery display from % to distance....it's all simple arithmetic anyway.

But I prefer battery status on %, and I can just monitor the nav KM remaining and determine whether I can drive a bit more aggressively or if I need to be conservative.

they are not taken into account by the trip computer. The trip computer has prooven itself to be quite inaccurate as has been discussed extensively here before.
It's great that it doesnt matter to you but this is not what I asked. The 15% left if you are at 30% if there is a supercharger has nothing to do with my question which specifically asks about the energy equivalence of 1 rated km/mile, not how far you think you can go with how many % of your battery. It is not simple arithmetic. you are just guessing, not using maths.

Your preference of battery status in % is only based on you being in europe and having superchargers every few km so you simply pull up to one when you are <30%. When you routinely drive your battery form high SOC to near 0 you would find km more useful, as when your rated range drops below the distance to destination you really gotta watch your consumption to stay below a rated km (not that that is what this topic is about though)

 

[XLR82XS]

Engineering Explained has a nice video about this.

 

[AlanSubie4Life]

In fact, we shouldn't need to derive it backwards. It's the solid line in the energy graph labeled "rated"

This line is always 5Wh/mi higher than the charging constant for the vehicle.

Yes, you can then derive all the numbers from there. However, the alignment with the trip meter will be imperfect.

I’m not sure why the question is being asked - the answers are tabulated in the Constants sticky. And new vehicles can be derived the same way.

Charging constant: calculate using the three numbers on the Energy Consumption screen at a high SoC: Remaining Rated Miles, Projected Range, and Recent efficiency.
Charge Const = ProjRange*RecentEff / Rated miles

Discharge “const” = 0.955*Charge Const.

Trip meter will agree with this discharge rate within a percent or two.

That’s all you have to do for any Model 3 vehicle, as long as Tesla keeps the buffer at 4.5%.

And of course you can calculate full battery capacity (only accurate for degraded vehicles though - will not be accurate, will be too low, for new vehicles) by multiplying charge constant times the rated miles @ 100%.