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Comment by dietsche | Hacker News Reader

As a Tesla owner, I think the source of the confusion is the EPA range displayed in the HUD on the Tesla. We toggled ours to show the battery percentage, which is much more useful to us.

We've never owned a gas vehicle that met it's EPA range and the Tesla is no different. No one takes EPA MPG * GALLONS of gas and expects it to be a real life estimate of range.

Wind resistance increases EXPONENTIALLY with speed. Drive a little over the speeds the EPA used to determine range, and the observed range will drop significantly as a percentage when compared to the EPA range for any vehicle.

If you do have a Tesla, you'll quickly find out that the trip computer is very accurate. The worst I've seen is a cold January day in Wisconsin (-10F) while on a road trip with a head wind. In that scenario, the trip computer was off by 7% mostly due to the head wind. In the summer, it is spot on usually within 1 - 2%.

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FWIW Our Audis (Q5, A6 allroad) have significantly better MPGs than the advertised ones

The Q5 advertises 28mlg on the highway but i consistently hit 30+ here

And the wagon hits 35mpg on the highway very often even though it only advertises 26. It actually turns off 2 of the 6 cylinders when it senses that it can.

Both cars I've owned have had better efficiency and thus range than advertised (a Honda and a Subaru). I'm often shocked at how I can get 38-40mpg + on a car that is supposed to be getting 29mpg.

Same here. I've come to the conclusion that most drivers (or most drivers that complain about EPA mileage ratings anyway) have insane driving habits. Every car I have ever owned (And I've run the gamut from sedans to light pickups of both American an Japanese make) has met or exceeded the EPA rated mileage.

The only oddity that I have observed is in my current car, a Lexus hybrid crossover just barely meets its city rating in town while easily beating the city rating (which is higher since it's a hybrid) on the highway. Not that I'm complaining, but it's not what I expected from my first hybrid vehicle.

> We've never owned a gas vehicle that met it's EPA range and the Tesla is no different. No one takes EPA MPG * GALLONS of gas and expects it to be a real life estimate of range.

Because gas stations are still far more common than fast chargers. We'll get there with EV charging, but right now range does matter, especially if you routinely see half of what was advertised.

I had a similar thought before we purchased our Tesla. Our actual experience has been much better than expected. Here's why:

1) Everyday Driving / Commuting: Much like an ICE vehicle where one thinks about 1/2 tank, 1/4 tank, etc... we think about percentages. For us, a round-trip to the in-laws is 50% in the summer and 60% in the winter, for example. Commuting round trip is ~15% in the winter, and ~12% in the summer. This combined with the fact that the car starts every morning charged to 80% means that we really don't ever worry about super charging in our day-to-day life.

2) Road Trips: The navigation software on the tesla automatically add charging stops where needed, and critically, it is very accurate when predicting range as a percentage when it knows your destination. We typically charge until it say we'll reach our destination/charging stops with 10%. That reserve has always been more than enough even on 1000 - 2000 mile road trips.

My general advice to anyone with a Tesla who has range anxiety: 1) Put the round trip into the trip computer. (e.g. Home => Place I Want To Go To => Home) 2) Always make sure you'll get to your next charging stop with 10 - 15% left according to the trip computer. 3) Relax and enjoy the auto-pilot :)

I agree generally, I've never really had a range anxiety problem on either of my Teslas. And 100% agree on the daily charging, too.

But I do think we're not to the point where we can just nonchalantly hit the road without really thinking about charging. It is part of the planning in more detail than I'd usually spend with a gas car. Totally manageable, but still.

Who are “we”?

Right now it varies a lot where in the world you are. I don’t have exact numbers but I have a feeling there’s more fast charging locations around me than gas stations. (There may be more gas pumps but it doesn’t matter because most EV owners here don’t use fast charging as their main method of charging)

I guess this is only true in like 2-3 countries in the world right now. But it’s changing very rapidly.

> We've never owned a gas vehicle that met it's EPA range and the Tesla is no different. No one takes EPA MPG * GALLONS of gas and expects it to be a real life estimate of range.

Why is this exactly? It's been true - MPG is lower than estimated - of every vehicle I've owned too except for my most recent, a '23 MX-5 (i.e. a sports car, which I tend to drive at higher RPMs and in lower gears.) I'm getting spot-on or a little above the EPA estimated on the car I'd least expect it.

(edited to clarify "it's been true")

Consider yourself lucky. Off the top of my head both Ford and Subaru were subject to lawsuits about vehicles not meeting EPA range expectations. When I had an outback I was very lucky to get 17MPG and the EPA range on the window sticker was 27 which felt really deceptive.

27 hwy? My 2013 STI gets like 23/19 on a good day and requires 93 oct or higher. oof!

My fuel efficiency is horrid and advertised to be horrid.

I’m surprised you’re getting such good economy. I was getting 13mpg in my 2013 in stop and go traffic. Which is all I drove in at the time, and a contributing factor in selling it.

FWIW, one of my vehicles which _does not_ get the EPA estimated is a 2017 Ford Fusion 2.0L AWD. EPA estimate is 20/29/23 (city/highway/combined.)

I normally get 21mpg combined, which is really not so far off. Lots of highway driving usually gets the average up to 23.5mpg. With that worst-case number, across a full tank of gas (16.5 gallons x 2 mpg), I'm shorted about 33 miles, or 8%.

Is that pretty comparable to what Tesla users see? The article claims it's much higher:

> Tesla was fined earlier this year by South Korean regulators who found the cars delivered as little as half their advertised range in cold weather. Another recent study found that three Tesla models averaged 26% below their advertised ranges.

I think the EPA estimate for highway is based upon a totally flat windless road at 55 mph

There's an EPA website for this.

https://www.fueleconomy.gov/feg/browseList.jsp

I have a 10 year old Mazda 3 and the MPG estimate is on target: 32 combined 28 city 39 highway estimate and I get 36 mpg. User average is 35.2.

My 2021 Honda CR-V doesn’t get close to EPA MPG but the range calculator is still accurate to within maybe 15%. I’ve tested it a few times driving from Oakland to LA which is right around the full range of the car and it gets pretty close- even with a whole mountain range to drive over north of LA. It doesn’t appear to use EPA MPG for its estimates and it makes for a better experience.

Both Tesla and this seems to be veering into the territory that VW did back then with emissions.

Aerodynamic drag increases as a square as a function of velocity, not exponentially.

https://en.wikipedia.org/wiki/Drag_(physics)

I think this is a problem because a lot of what people use to shop an EV is the headline range number, which you are declaring is not accurate. This is false advertising.

Sure, but isn't it up to EPA to fix their testing methodology to get better estimates? Why do we expect car makers to do that?

If the EPA rating is consistent in it's overestimation, it would still be a perfectly functional system to comparison shop range. Putting that KNOWN overestimating number as the headline "range" estimation is wrong. My ICE car does not use the EPA combined estimate for my range because that would be inaccurate and make the number useless. The knowledge on how to build a useful "Range" value in a car has been constant since at least 2000, and yet Tesla, and ONLY tesla, seems to have it wrong. Meanwhile, as others tell, the navigation display shows a very accurate estimation, so why the disconnect? There's no requirement for a battery display showing the EPA range, they CHOSE to do that.

Tesla shows you percentage by default. The percentages for arrival in navigation are spot on for most people.

What do you want them to do? give you a table with your range for each combination of illegal speed, inclination and wind speed?

My EPA highway mile rating is lower than I see in actual driving in my ICE. City is about accurate unless I’ve been in a lot of traffic’s with its look back range for live mpg estimates. Lots of owners of other EV brands and the article itself said they’re much better than Tesla’s estimate as well. It’s difficult to see how the issue is anything but specific to Tesla and its method of presenting info to consumers. They were even force to lower their previously stated range, per the linked article.

I had a Mazda 3 once which would routinely beat its EPA estimates, especially highway driving. You are too forgiving of Tesla's business gimmicks

>Wind resistance increases EXPONENTIALLY with speed.

And the power required to move against the air is the cube, not the square!

Neither v^2 nor v^3 is exponential. They are polynomial functions. Exponential would be if wind resistance or power or fuel consumption were c^x for some constant c.

It seems to have become fashionable to say "exponentially" or even "EXPONENTIALLY" when you mean it's a rapidly increasing function, but to the technically-minded, whom I would hope to find on HN, there is still a clear-cut difference between exponential and polynomial.

I think the fact that polynomials contain an exponent forgives that particular degradation of precision in the vernacular. I corrected the OP by adding context so onlookers could know just how fast the power requirements grow without poo-pooing their choice of words. In a programming context, extacting language precision is beneficial. Shooting the shit in an Internet forum I think we can tolerate imprecision in others without causing a dust up. Now tell me how do you feel when someone says “it’s pretty unique”

I drove a Tesla for over a month and it was a relief to go back to my Honda Civic. The range (both miles and %) was wildly inaccurate. If I had to drive anywhere that wasn’t a few miles within the city, I was under constant anxiety. No thank you.

It’s a wonder to me that anyone would ever trust anything Elon Musk ever says about anything. He’s a proven liar and creates an openly hostile, negative culture wherever he goes. I feel sorry for people who are caught up in his lies, either customers or employees or people who work closely with him and have to suffer his tantrums. There was a point I admired him, but that is long past.

I can’t credit myself with the observation, it was someone else on HN, but it ran something like this:

For years Tesla made cars that were disproportionately appealing to people with concerns about the environment, a population that skews liberal/progressive. Those on the other side of the political world view might like the cars too- especially technophiles— but there certainly a large contingent that are skeptical to anything with a primary appeal of being “environmentally friendly”. Then comes the current culture-war driven political ecosystem, and all musk has to do is tweet some controversial things that might resonate with some contingents on the political right and all of a sudden those individuals may feel more comfortable buying cars from a guy who speaks their language.

I certainly don’t know if that was Musk’s deliberate strategy though, but it wouldn’t shock me if his actions in that way are partly “him” and partly him leaning into a role of social prominence that resonates with a consumer population previously less likely to buy his cars.

It would be interesting if I could fine surveys of automobile brand customer bases broken down by political affiliation, and if it’s shifted Tesla’s at all in recent years.

You can see his conversations leaked by court docs and understand his politics clearly. No need to contort yourself into seeing him in some other light than the one that’s readily apparent

> We've never owned a gas vehicle that met it's EPA range and the Tesla is no different

Car and Driver's EPA range versus real world highway tests:

https://www.caranddriver.com/news/a43657072/evs-fall-short-e...

EVs are quite different to ICE when it comes to EPA range ratings.

The article says that Tesla knowingly overestimated their numbers. Tesla even switches the range algorithm to be more accurate when mileage gets to 50%.

I think the difference is that a gas-powered car will keep driving when the gas indicator hits zero. You can still get a couple dozen miles at that points, and those are so important. Tesla is really doing you a disservice by not considering that.

Supposedly you can get some range with the Tesla at zero - it’s just a bad idea to do that.

It’s a bad idea in a gas car too, my friends that have run out of gas did so because of driving on E.

Though at least with gas it’s easier to bring it to the car.

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