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You have it backwards. The car serves you. You should not have to serve the car (beyond universal, traditional things, like the need to maintain, insure, etc.).

It’s reasonable to ask for a range estimate that’s not naively optimistic.



Consider sprint estimates and story points. We have those discussions regularly here too and the HN community is very sympathetic to the line that those estimates can’t be accurate and involve too many unknowns and externalities. Why should this be different?

And did anyone ever scrutinize gas vehicle tank estimates closely? I think one of the issues is the absolute lower range of EVs. You can feel it more when a 250 mile range is off than when a 400 mile range is off.

That said, I road trip in my Y all the time. Still hasn’t really bothered me. And I usually drive at 80 mph.


Every gas car i have driven UNDER-estimates the range. And I am driving the car not looking for drafts and driving 20 under the speed limit.


That’s never been the case. Drive down moderately steep grades and shift to a low gear to spare you breaks, for example. It’s the same argument. We don’t drive black boxes. Anecdote, a relative drove trucks in the Korean War and after, his vehicles lasted much longer per miles driven without maintenance due to how he drove.


Would you expect manufacturers to publish maintenance schedules assuming everyone drives like your relative, or based on maybe the 25th percentile of how people actually drive?

IMO product designers should not assume that the typical customer is a hyper-optimizer.


> IMO product designers should not assume that the typical customer is a hyper-optimizer.

It’s not just an opinion. If you design that way, you’re misrepresenting truth for the vast majority of drivers.

Hard to distinguish that from lying.


What is that number though? Do you just assume every driver just mats the go pedal and slams the brakes at every stoplight? Battery life is a bit non deterministic. Yes you can track driving habits but I don’t know that I always drive the same way depending on how much of a rush I’m in and other factors.


It is not naively optimistic. I just finished a 2500 mile drive with a Tesla Y and its estimates are pretty much within 1-2% of my actual usage.


As the article (or another poster) points out, you get a different algorithm when you look at the dash on a random day vs. when the Tesla knows you are going on a trip. That's even more damning to me.

Edit: Also a different algorithm when below 50% charged. As some of the replies point out, a destination does supply more information. The current charge level does not.


When going on a road trip Tesla calculates the time based on the route you put into navigation.

Obviously it will give a different estimate than stop and go traffic and starting the vehicle without pre-conditioning the battery.

Tesla does a great job with their scheduling functionality that lets you pre-condition battery before you leave and even when you near a supercharger to maximize charging efficiency of the battery.


That makes sense. But if Tesla is going to do that, surely their less informed estimation shouldn't be so naive and use historic data. Why would Tesla guess I'm in stop and go traffic when it knows I spend 80% of my time on a highway. Shouldn't it aim for either the most accurate or most conservative naive number?

As the article points out, it also switches to a significantly more accurate estimation once the battery is half discharged.


How does the Tesla know I'm going on a trip?

Are you implying its strange that the Tesla can calculate a more accurate range estimate when you literally tell it where you want to go to its computer which can use map data to calculate energy usage, versus you just driving around in circles in a arbitrary area and the computer only can assume based on EPA average usage?


> computer only can assume based on average usage

It is clear from the discussion that it isn’t basing it on that at all. Would be overjoyed if it was based on average efficiency for the last 50 miles I drove. It isn’t.


I meant EPA average usage. And good it shouldn't.


Very few people attain EPA average efficiency, so insisting on putting a range indicator based on EPA averages seems silly.

Most ICE cars calculate range based on a long term average of a person's usage with some small amount of pessimism. Why should an EV do worse?


It doesn’t use average usage to calculate the remaining range, it uses EPA numbers which are 200 Wh/mi or less. Which, interestingly, is less than the consumption shown on the Monroney sticker. How they can show two contradictory numbers on the same official document is fascinating to me.


I meant EPA average usage


That’s how it’s supposed to work. EVs, to a fault (some may argue), are so efficient that any change in driving condition can have a major impact on range.

Eg. Having a window down, slope, number of passengers, etc.


They’ve never hidden that the range displayed on the screen is assuming the EPA estimate for the car? The actual range depends on what the route is going to look like, and adjusts based on how much your usage so far has been.

Like, this is painfully clear to the drivers of this car vs what this article is suggesting.


>> The car serves you

The user will get more value out of any machine if they develop an accurate mental model of how it operates.


I agree. I’ve rebuilt cars. I get it.

Knowing the best way to use something is not the same as serving it.


I guess I don’t understand what it means to serve something in this context or how it is relevant.


Personally I'd find the information valuable, it tells me how my habits affect the efficiency.


> The car serves you.

Physics serves no one. It is.




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