Supercharger speed: 116kW

[TonyWilliams]

The EPA data is 80.X kWh maximum capacity, 78.X kWh usable.

Those tested cars had “4000 miles” minimum to season the onboard emission equipment (of which Tesla has none).

Folks can certainly use any datapoint that makes them happy (73-78kWh), but the car should be able to go the Tesla adjusted EPA range at 70mph on flat hard surface roads with no wind, with a warm, new condition battery:

78kWh * 4 = 312 miles

I made just two logged data points for Model 3 LR consumption in ideal conditions (level hard surface road, no wind, warm weather, no significant battery / cabin heating or cooling, no degradation):

70mph - 4.0 miles/kWh (250 watthours/mile)
112km - 6.43 km/kWh (155.5 watthours/km)
17.5kW consumption rate

90mph - 2.7 miles/kWh (370 watthours/mile)
145km - 4.35 km/kWh (230 watthours/km)
33kW consumption rate

Calculating for aerodynamic drags, we should have double the consumption rate at 90mph than we do at 70mph, using a simple calculation of velocity cubed:

(90 / 70) ^3 = 2.12 (about double)

 

[TonyWilliams]

The 77,2kWh comes from EPA testing, as "Charge depleting range". Aka, they drove the car on a dyno until it would go no further, which likely was indeed past the reading of "0".

Not quite accurate... the test runs until the vehicle can’t hold the speed.

 

[KarenRei]

The data points on the graph are “raw data”... empirical observation. No estimates.

Okay, so you don't actually know the curve at the low end, then? That's just a guess?

Thanks for the temperature info, that's important.

 

[TonyWilliams]

... I stop at the same 5 chargers. They never give same numbers. There to many varibles, ie. What is left in your car? Are you alone on your charger munber or sharing paired? What is the outside temp? ... you are chasing a ghost if you expect to get perfect consistant numbers.

Outside temperature only matters if the Supercharger gets too hot, and must reduce the charge rate to keep from overheating. Battery temperature will be “normal” if you’ve been driving the car for the past 100-200 miles.

So, the more pertinent variable is battery temperature, which can be at ambient if the car was neither charging, nor driving for the previous bit of time, or, if being used, the battery can be many degrees hotter or colder than ambient.

What’s left in your car battery (SOC%) doesn’t change the comparable charge rate. If two identical cars plugged into the same Supercharger (at different times, not at the same time), and both cars have 50% SOC, then they both will charge at the same rate (plus or minus some small variation). As your battery degrades over time, the charge performance will be reduced.

If your battery is warm, and you’re not sharing a Supercharger, the only other real variable is the actual condition of a particular Supercharger. Like you, I’ve been at a Supercharger that just didn’t perform to it’s potential. Just move to the next one when that happens!

Also, even if your car starts its charge at the predicted rate (say, for instance, 116kW below 45% with a warm, new condition battery), there is no guarantee that it will be continuous. I check the rate periodically with the app to make sure I’ll be done charging in the anticipated rate, or whether I need to move the car elsewhere for charging.

 

[gregincal]

The EPA data is 80.X kWh maximum capacity, 78.X kWh usable.

Those tested cars had “4000 miles” minimum to season the onboard emission equipment (of which Tesla has none).

Folks can certainly use any datapoint that makes them happy (73-78kWh), but the car should be able to go the Tesla adjusted EPA range at 70mph on flat hard surface roads with no wind, with a warm, new condition battery:

78kWh * 4 = 312 miles

I made just two logged data points for Model 3 LR consumption in ideal conditions (level hard surface road, no wind, warm weather, no significant battery / cabin heating or cooling, no degradation):

70mph - 4.0 miles/kWh (250 watthours/mile)
112km - 6.43 km/kWh (155.5 watthours/km)
17.5kW consumption rate

90mph - 2.7 miles/kWh (370 watthours/mile)
145km - 4.35 km/kWh (230 watthours/km)
33kW consumption rate

Calculating for aerodynamic drags, we should have double the consumption rate at 90mph than we do at 70mph, using a simple calculation of velocity cubed:

(90 / 70) ^3 = 2.12 (about double)

I'll be interested when somebody actually tests the charge depleting range for themselves in a real production 3. In the meantime, I'm not going to be the first to see how far it can go past 0. The Model 3 seems to calculate a rated mile at about 235 wH. It shows a total range of about 310 rated miles for a displayed usable capacity of about 73 kWh. Interestingly, though, I also find it easier to beat rated range in the 3 over the Model S, so even without that extra capacity I'm pretty pleased with the range.

 

[TonyWilliams]

... The Model 3 seems to calculate a rated mile at about 235 wH. It shows a total range of about 310 rated miles for a displayed usable capacity of about 73 kWh.

Where did you get this “displayed” usable capacity (versus the actual data from Tesla at 78.X usable)?

 

[TonyWilliams]

Another interesting feature is that the Model 3 shows 25% remaining at the destination as the “ready to continue” notification amount, whereas on model S that was 7%, and now to 10%.

25% of a 310 mile range car is a LOT !

 

[TonyWilliams]

Okay, so you don't actually know the curve at the low end, then? That's just a guess?

Thanks for the temperature info, that's important.

If you’re asking about the charge rate below 6% SOC, no, I didn’t observe that.

 

[Owner]

Huh? Are you talking about a charge rate of 45 kW or that you added 45 kWh to the battery?

I think

Outside temperature only matters if the Supercharger gets too hot, and must reduce the charge rate to keep from overheating..

Not entirely true. If it is hot outside, the car uses energy to keep itself cool, and if you are inside the cabin cool.
If it is really cold outside, it also expends extra energy.
I've never measured these effects but it definitely took longer to charge in South Dakota on my cross country trip than in California.

 

[KarenRei]

If you’re asking about the charge rate below 6% SOC, no, I didn’t observe that.

I'm more asking as to whether you observed the charge rate at 6% and during the rampup to 116kW. I'm trying to fill in the Model 3 charging performance at low SoCs, but I can't just add guesses as datapoints

 

[KarenRei]

Not entirely true. If it is hot outside, the car uses energy to keep itself cool, and if you are inside the cabin cool.

Additionally, the effectiveness of the radiators is proportional to the difference in temperature between the hot coolant and the ambient air temperature.

 

[K-MTG]

Huh? Are you talking about a charge rate of 45 kW or that you added 45 kWh to the battery?

If you don't know why I'm asking, I and others have posted about wrong unit usage many times, when it comes up. Example: Usable KW Doesn't match up??

Meant 45 kW charge rate...my auto correct keeps changing kw to kwh

 

[TonyWilliams]

I'm more asking as to whether you observed the charge rate at 6% and during the rampup to 116kW. I'm trying to fill in the Model 3 charging performance at low SoCs, but I can't just add guesses as datapoints

I didn’t pay super close attention, but yes, it clearly went to and held 116kW until about 45% SOC. It had to in order to add 125 miles (200km) in 15 minutes.

 

[TonyWilliams]

INot entirely true. If it is hot outside, the car uses energy to keep itself cool, and if you are inside the cabin cool.
If it is really cold outside, it also expends extra energy.
I've never measured these effects but it definitely took longer to charge in South Dakota on my cross country trip than in California.

Yes, the car uses energy to keep both you and the lithium battery hot or cold. So, two identical cars would charge atl the same rate (plus or minus some small variation).

If you charge once in 70F weather, and once at -30F weather, the colder one will absolutley consume more heating power, however, the temperature of the battery is a key ingredient to charge rate.

 

[gregincal]

Where did you get this “displayed” usable capacity (versus the actual data from Tesla at 78.X usable)?

I thought I just explained. The display in the Model 3 (at least in my car) show a drop in the rated miles remaining equal to the actual miles driven when the wH/mile is about 235. It counts down the rated miles remaining starting at 310. .235 * 310 is 72.75, and that seems to track pretty closely with the battery remaining % dropping compared with the displayed kWh used, although because they only display whole number kWh used it's a bit rough. Just a question since I've never driven it that low, when you did the 200 mile drive that dropped you to 6%, how many kWh did the car say you used?

 

[KarenRei]

I didn’t pay super close attention, but yes, it clearly went to and held 116kW until about 45% SOC. It had to in order to add 125 miles (200km) in 15 minutes.

It's not a question of how high it got, it's a question of where it started at and how quickly it got to 116kW. Some people have reported 117kW; nobody is doubting 116kW Did it start out at ~55kW, ramp up to 90kW almost instantly, take 2 minutes to get up to ~112-113kW, then slowly ramp up to 116kW?

Also, you claim here that it held 116kW to 45% SoC, but that's not what your graph shows. Your graph shows 110kW at 45% SoC, having declined from 116kW.

Again, I'm trying to determine what's real and what's just drawing issues / guestimates

 

[wwu123]

It's not a question of how high it got, it's a question of where it started at and how quickly it got to 116kW. Some people have reported 117kW; nobody is doubting 116kW Did it start out at ~55kW, ramp up to 90kW almost instantly, take 2 minutes to get up to ~112-113kW, then slowly ramp up to 116kW?

Also, you claim here that it held 116kW to 45% SoC, but that's not what your graph shows. Your graph shows 110kW at 45% SoC, having declined from 116kW.

Again, I'm trying to determine what's real and what's just drawing issues / guestimates

Seems like you're splitting hairs here. My eyeball of the graph is more around 112kW at 45%, and the 4kW is not necessarily what everyone would agree is taper; there's a certain amount of "kW sag" in nearly every supercharging session at the high rate, my presumption is probably inefficiency from various cable and components heating up, before the taper kicks in. Where taper truly starts is a matter or interpretation.

And on the front end, the initial ramp is extremely variable session by session, sometimes it jumps up immediately, sometimes it hits a midpont and creeps up, sometimes, it drops down to zero once or twice before jumping up to the high rate. There's very little I'd infer from this charging session to the next charging session.

All speaking from Model S observations (I have every charging session, Supercharger or not, logged in Teslafi.com).

 

[KarenRei]

I'm not "splitting hairs", I'm doing data collection.

 

[apacheguy]

You are splitting hairs. 110 vs 116? I mean come on, we are talking a 0.1 kWh/min difference. That is well within the noise of the data set.

 

[KarenRei]

It's a 5 1/2% difference. It matters. More to the point, it helps define the shape of the curve around it.

I don't know why you're making a big deal about someone who maintains a spreadsheet of model 3 charging datapoints simply asking questions to make sure that the data in said spreadsheet is correct.