I used percent this past weekend because I was on a trip and both the nav and abrp calculate in terms of percentage left. I like the fact that on a road trip, I know that if the battery gets to zero, I'm out of juice and when it gets to say 10%, I need to figure out a place to charge. I don't like the fact that using distance is a joke and that Tesla does some pretty shady crap with their distance calculations. i'm sure half the Tesla owners on here wouldn't have bought had they known that the range being advertised is complete BS. Its a car, if you can't use the heater and A/C and get the rated mileage, it don't count. If you have to drive 55 to get it, it don't count. LOL. I may stick to percentage at this point, but that is really only useful on a road trip when you are going charger to charger. Around town I'd actually like a real visual of miles left and I'd like it to be somewhat accurate.
Your frustration is understood, but this isn't some "shady crap" (at least not just from Tesla).
Others are right. Your frustration is with the EPA, or rather rating agencies in general. Simultaneously, your frustration is with the general lack of understanding in the world of how to represent an EV's rated efficiency to the whole population.
Take miles per gallon. Miles. Gallons. You know what these things are. You put in gallons at the gas station, and you travel miles. You are given a city rating and a highway rating in MPG. Or L/100km, or whatever units your country uses.
There was no reason for the ol' gas cars to display a "rated range". No one treated it like that, because fueling is easy and readily available everywhere. In comparison, fast charging infrastructure is still an order of magnitude slower than fueling a gas vehicle, and it's
way, way more sparse.
Combine that with this info: for an EV, you "fuel" it with kWh and you travel miles (or km). What's a kWh to the average person? No idea. Heck, I don't even really look at my own electricity bill. Utility company says total due, we pay total due. It's not like I have a meter ticking by the light bulbs, TV, washing machine, etc. telling me how much "fuel" they've gone through. I have almost no point of reference for kWh even though it used electricity every day.
And then, charging is complicated. You don't want to dip below 10% (basically wouldn't want to for gas either), and not go above 90% routinely. Does that mean they should only advertise 80% of achievable capacity? Why should they be forced to down-market their numbers when their cars are capable of more?
This is absolutely, positively, 110% a regulation and standards problem. I'd love a "Daily Range" figure (accounting for the 10-90% recommendation, for example). I'd love separate ratings for cold and warm weather. And we still need ratings separately for city and highway. These all complicate things and consumers hate that. I've basically said we need... 6 numbers or so? Compared to 2 for gas vehicles?
You also can't just apply this to all EVs moving forward. Maybe 10 years from now, the standard battery chemistries don't give a rip about being charged to 100% and everyone does that daily. Maybe they've all figured out heat pumps better and winter range doesn't universally suck as much as today. Maybe not everyone has these things fixed, so the comparison between vehicles still needs to be clear. Informing the consumer concisely and meaningfully is
hard.
EDIT: I forgot a tangent. Wh/mi or Wh/km. Those are the "equivalents" to things like MPG or L/100km. Without a frame of reference, those are entirely meaningless. You basically have to drive EVs for a bit
and track that before it has any meaning to most people right now. However, "rated range" is far more familiar, even if it comes with a bunch of caveats. So the advertised thing is currently range (based on ratings) rather than efficiency (Wh/mi).