Percentage or Miles/Kilometers : which do you use and why?

[Rocky_H]

After reading most of this thread, I decided there might be merit to using miles, so I tried it this morning.
It lasted 30 seconds before I realized precision doesn't equal accuracy. It makes no difference if miles is more precise, because it's not accurate.

Wow. I don't get it. It's a given that any kind of measurement that you're using to make a prediction about the future can't be exactly accurate, so why does that upset people? It's a ballpark, a generality, a wet finger in the air. If you see 151 rated on the display, and you have to drive 114 miles, you can say, "Oh, yeah, looks fine." It doesn't have to mean that you will be able to drive exactly 151 actual distance miles regardless of future conditions--that's not what it's about, because there is no telling if you are going to drive 50 miles per hour or 73 miles per hour or how warm you want the car while you drive, etc. It's almost certainly going to work out to something a little different than exactly 151. But why is that so bothersome? Seeing that the display is some reasonable amount higher than what you have to go, says you've got some margin to work with. Same or less would be: probably don't try that without charging.

Using percent is just sticking your head in the sand.

Yep.

 

[gecko10x]

I'd actually be much happier with a reasonable minimum range displayed.

 

[jerry33]

I'd actually be much happier with a reasonable minimum range displayed.

The problem is that "reasonable" depends on circumstances (weather and terrain), so no one is going to be happy with it. There's really no way to do that. Rated Range is about as reasonable as you can get. Ideal Range is closer. The percent remaining at the destination shown by the Nav system is better than either.

 

[vinnie97]

My annoyance that both can't be displayed simultaneously continues to irritate. This surely can't be a insurmountable request.

 

[PianoAl]

My annoyance that both can't be displayed simultaneously continues to irritate. This surely can't be a insurmountable request.

Same here. There is a "fashion" trend in interfaces to eliminate data (more white space). Sometimes it goes too far.

 

[PianoAl]

An Analogous Situation:

We got our Leaf in 2016. It only has percent and the (useless and never used) guessometer. I had LeafSpy (ODBII Reader) and knew I should get used to thinking in kWh (or GIDs), but I never got around to it.

After three years, the battery had degraded enough that the SOC didn't mean the same thing it used to. For example, at the beginning, if we had 22% at a particular landmark, we knew we'd make it home. After a few years of degradation, those numbers didn't work any more. If we had 22% at that landmark, we wouldn't make it home.

Although I expect much less degradation with our M3, I won't remake the mistake of thinking in terms of SOC percent.

 

[AlanSubie4Life]

Although I expect much less degradation with our M3, I won't remake the mistake of thinking in terms of SOC percent.

It is nice that as obfuscated as it may be, the Tesla (mostly) unambiguously provides the energy it thinks it has remaining. It’s great.

My Spark EV has a similar less than useful GOM. Fortunately it has a kWh tracker as well though so at least I can keep track of my battery status if I do an occasional deep discharge. 20% so far after ~25k miles and 3 years!

Expect about 10% with your Tesla (about 286 rated miles, 70.2kWh). Some people do a bit better, others a bit worse! Hopefully you will luck out!

 

[DopeGhoti]

, the Tesla (mostly) unambiguously provides the energy it thinks it has remaining.

Even more unambiguous though would be displaying not 'rated' miles, or state of charge in terms of percentage, but state of charge in terms of kilowatt-hours.

 

[David99]

Even more unambiguous though would be displaying not 'rated' miles, or state of charge in terms of percentage, but state of charge in terms of kilowatt-hours.

You can get that info on the CAN bus. I have it on my dash using ScanMyTesla all the time. I found it less useful than I first thought. Mostly because it doesn't relate to anything that would tell me how far I can go. The best method to see how far you can go is the energy graph (unfortunately not available on the Model 3). It takes recent consumption into account and calculated based on actual data from the roads that you are going on heading to your destination. Elevation changes and average speed on those roads are properly considered.

The other reason kWh isn't that useful is because it doesn't help comparing different cars. Rated miles is the best way to compare. It is energy normalized to the different cars. 10 rated miles in a Model 3 are the same as 10 rated miles in a Model X. They represent different amounts of energy but are exchangable between car. If you know you need 75 rated miles to get somewhere in your Model S, you can tell a Model 3 or Model X owner to make sure to have at least 75 rated miles in their battery to make it.

 

[AlanSubie4Life]

The best method to see how far you can go is the energy graph (unfortunately not available on the Model 3). It takes recent consumption into account and calculated based on actual data from the roads that you are going on heading to your destination. Elevation changes and average speed on those roads are properly considered.

The Energy Consumption and Trip Planner are available under the Energy app in Model 3.

 

[David99]

The Energy Consumption and Trip Planner are available under the Energy app in Model 3.

Correct me if I'm wrong, but I think it only shows the arrival percentage, but not this screen.

 

[AlanSubie4Life]

Correct me if I'm wrong, but I think it only shows the arrival percentage, but not this screen.

It shows that screen (the green/yellow/red line), under the Trip Planner tab. Cool video though, didn't realize that's how it behaved when cutting it close (I always try to make sure I charge until 15-20% predicted, for plenty of margin, and then really get some speed going).