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Electric Vehicles

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Yeah, that's a weird hill to die on. Range estimators have been around since what? The nineties?

My brother is fond of telling the story about the time he towed a water tank, on a trailer, on the way out the guessometer was freaking out. (Because they always assume that the current state is the permanent state when calculating range remaining).

On the way back it was saying:

1, 2, 4, 8, 16, 32 etc. etc. (As it struggled to deal with the fact that the trailler wasn't such a drag anymore). It started making meaningful predictions again the following day.

Did that guage use Microsoft's download meter system?
 
My Subaru does it pretty well. It seems to be taking some sort of rolling average mileage as the baseline. When I get out on the highway, the range estimates will start increasing as I am getting better mileage.
They all get better as you get closer to empty. The issue is that the initial range is just a guess based on your previous driving habits and conditions. With an ICE, you are seldom starting with a full tank so you are not nearly as likely to notice that your actual range isn't what was predicted when the tank was full.

But with an EV, you usually have the equivalent of a full tank every time you first set each day. And with less overall range and people monitoring their range more closely, it can be more obvious when that initial estimate isn't what you end up getting. I guess people also don't seem to get that the published range is also just an estimate.

Plus EVs are new and there are a lot of people trying to disparage them for whatever reasons.
 
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Nonsense. Most ICE cars manufactured nowadays do in fact offer such estimates, and they vary just as much for exactly the same intractable reasons.
Agreed. I have a car where my habit is to leave the odometer display set to show remaining range as I find that easier to keep an eye on than the fuel gauge. Car's over a dozen years old.
 
I can significantly reduce my highway range just by increasing my cruising speed by 20mph. And just like an EV, my ICE range estimator cold sucks at predicting I'm going to do that. It has no trouble adjusting to the new reality and revising its estimate, though.
 
Agreed. I have a car where my habit is to leave the odometer display set to show remaining range as I find that easier to keep an eye on than the fuel gauge. Car's over a dozen years old.

Not being funny, but I consider my journey and eyeball the petrol gauge. If it isn't "plenty" I put a decent top up in the tank.
 
One nice thing is that some newer cars integrate navigation into the "guestimate" so that speed and terrain are considered. My i3 did that. Not sure if the Ioniq 5 does.

In any case, I don't think any of the EV manufacturers advertised range figures in the US that are out of line with the EPA estimates. So, the lawyers are going to have a hard time supporting the argument that the figures were inflated.
 
There was a reason the functionality was called the "guessometer" - this seems to have been forgotten

That's what we called it with my 2013 Nissan Leaf, and still hear it when talking about older Leafs. Haven't heard it when referencing more modern cars. Electric cars have come a long way in a decade.
 
Electric cars have come a long way in a decade.

Even now the range estimates are just that - estimates.

But one nice thing about Tesla’s is that frequent over-the-air updates improve on existing functions and add new ones.

The “Energy” screen is much improved since we took delivery of ours in Feb 2022. The current one:

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It now allegedly allows for speed, elevation change, temperature and wind to constantly update miles remaining. I find the % remaining at the next Supercharger or destination ends up being with a couple % of that predicted. And if the car sees you may come up short, or if your next Supercharger may have a wait, it will reroute you to a different/closer one. But it may nag you first that you need to slow down a bit to make it. It’s all really quite amazing - and it keeps getting better!
 
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It's still an estimate though, because the car doesn't know, precisely, how it will be driven, over what type of terrain, or what the weather will be like... just like an ICE car
 
It's still an estimate though, because the car doesn't know, precisely, how it will be driven, over what type of terrain, or what the weather will be like... just like an ICE car

The Tesla energy screen is aware of the terrain on the selected route. It also responds to driver behavior. Slow down and after a while the estimated charge at the destination will increase.
 
My 2013 Hyundai has a range estimator, which is quite unsophisticated, based on when the fuel warning light comes on, which is related to gas left in the tank. Simple but consistent if your fuel economy is fairly consistent, and pessimistic enough that you won't run out if you heed it.
 
The Tesla energy screen is aware of the terrain on the selected route. It also responds to driver behavior. Slow down and after a while the estimated charge at the destination will increase.

That makes sense, so when you are at a total stop it lets you know the remaining range is infinity!
 
That makes sense, so when you are at a total stop it lets you know the remaining range is infinity!
No. The car still consumes some power while at a stop. When stopped it is the least efficient. :)
 
No. The car still consumes some power while at a stop. When stopped it is the least efficient. :)

I wonder what the maximally efficient speed is for an electric car.

For internal combustion engine cars, from what I understand it's actually kind of complicated. I know that running the engine too slow is inefficient, but so is running the engine too fast. But I think it's even more complicated than just having a peak efficiency RPM. I've read about hypermilers who would accelerate to some high speed and then coast in neutral with the engine off until they slowed down, then accelerate again, rinse & repeat. That suggests that maximum energy efficiency for a gas engine occurs at moderate speeds but while accelerating, so that some of the energy is going to accelerating the car, it's not all going to fighting friction.
 
"Hyper-milers" look for a big truck to drop behind and "draught" or "draft." To be honest, I've stopped looking at EV forums, so normalised has EV driving become for us
 
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