[HN Gopher] Tesla has a range inflation problem
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Tesla has a range inflation problem
Author : rntn
Score : 41 points
Date : 2023-07-27 20:07 UTC (2 hours ago)
(HTM) web link (techcrunch.com)
(TXT) w3m dump (techcrunch.com)
| pkaye wrote:
| How good are range estimates on ICE cars and other electric cars.
| How do other electric cars handle cold weather estimates?
| olyjohn wrote:
| Range estimates are shit on ICE cars too. They're called
| "estimates" for a reason. You can't predict the future. I'm not
| a Tesla fan but this whole thing is nonsense.
| acqbu wrote:
| Always has. Nothing new under the sun
| https://lemmy.world/post/1319083
| dmonitor wrote:
| i didn't realize buying a tesla was a moral failing. i guess
| i'll but from an ethical company like GM instead
| mtmail wrote:
| related with 600 comments "Tesla created secret team to suppress
| thousands of driving range complaints"
| https://news.ycombinator.com/item?id=36891642
| zgluck wrote:
| This is blogspam, the actual article is here:
|
| https://www.reuters.com/investigates/special-report/tesla-ba...
| Nonlin wrote:
| I've always been concerned about the accuracy of the degradation
| of the range/the range in general.
|
| There is no real concrete way to tell if they are lying because
| the source raw data is obfuscated.
| diebeforei485 wrote:
| This is a more complicated problem than it seems because even
| determining the remaining battery percentage is non-trivial with
| lithium-ion batteries. Apple has an entire team dedicated to
| this.
|
| Predicting the remaining range is another step of complexity. I'm
| not saying it can't be done, but they should definitely sandbag
| the estimate.
|
| Some of the features using energy when parked, like sentry mode
| and cabin temperature maintenance, probably consume power and add
| to customer frustration as well.
| tzm wrote:
| Has or had? The Reuters article opens with: "About a decade
| ago.."
| Booktrope wrote:
| Big news, automobile manufacturer inflates gas mileage! Really!
|
| If anyone here has had a car that actually got the stated mileage
| in real world conditions, please let me know.
|
| I live on top of a hill and every single car I've ever owned,
| including, Honda, Toyota, Ford, Nissan, Dodge, Volvo that I
| recall right now has gotten oh, about 30% lower mileage than
| advertised. due to that pesky law of gravity that requires energy
| to be expended going up and down.
|
| But even when I lived in leveller locales, cars never got the EPA
| rated mileage, except once, when I drove a Honda with a CVCC
| engine on a road trip through level countryside at about 45 miles
| per hour all day. I got terrific mileage. I never did it again.
| Sohcahtoa82 wrote:
| > If anyone here has had a car that actually got the stated
| mileage in real world conditions, please let me know.
|
| I owned a 2016 Subaru BRZ, stickered at 24 mpg city/30 mpg
| highway, and over the 3 years I owned it, I averaged 32 mpg.
|
| My previous car was a 2000 Suzuki Esteem, stickered at I think
| 27/32. I averaged 28 city, 35 highway.
|
| I now have a Model 3 Performance, estimated 300 mile range. I
| get 230-270 miles depending on the weather.
| Marsymars wrote:
| > If anyone here has had a car that actually got the stated
| mileage in real world conditions, please let me know.
|
| Depends on driving style. I drive a manual Ford Fiesta (with
| worse specced fuel efficiency than the automatic) living in the
| foothills of the Rocky Mountains, and it's abnormal for me not
| to get better fuel economy than the automatic's spec.
| kccqzy wrote:
| Your comment is just publicly broadcasting your ineptitude at
| efficient driving. I regularly beat EPA estimates in both the
| EV I have and the ICE car I had.
|
| You can read more about EPA mileage testing:
| https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P100IENB.TXT I've
| personally found it to be fair and reflects the real world
| quite well.
| jstarfish wrote:
| > The Korea Fair Trade Commission also found that Tesla failed to
| inform owners that cold weather can reduce its cars' range. The
| commission cited tests showing Tesla cars lost up to 50.5% of the
| company's claimed ranges in cold weather.
|
| Ouch. I've had trouble with _cameras_ not working for long in the
| bitter Korean cold.
|
| I don't understand how this became a problem, much less one that
| was discoverable.
|
| If they're still selling extended-range batteries as DLC, just
| give the customer the extra capacity for free but spread it out
| over the service life of the battery (doesn't Apple do this to
| keep battery capacity constant?). They won't be buying the
| upgrade for a 10 year old battery anyway, so might as well use
| the extra material for _something_ and avoid this sort of PR.
|
| Or dynamically give/take away exactly enough of the unpaid-for
| reserve capacity to be able to consistently deliver whatever the
| promised range was. Unlock the remaining extra capacity as the
| upgrade. By the time people start noticing the _extra_ range isn
| 't working as advertised, you can gaslight everyone over
| inconsistent usage patterns across aging cars.
| machdiamonds wrote:
| It's very easy to see how favorably or unfavorably Tesla's
| claimed range compares to competitors based on independent tests
| of multiple EVs in the same conditions:
|
| https://www.youtube.com/watch?v=6LWL90paufE
|
| https://www.youtube.com/watch?v=ynCaTDR4rDQ
|
| https://www.youtube.com/watch?v=eFB6hsYXDiA
|
| https://www.youtube.com/watch?v=fvwOa7TCd1E
|
| Spoiler alert: Tesla models fare about as well, if not better,
| than their EV cousins, hitting around 80% of the stated range in
| the wild.
| mlyle wrote:
| We're not talking about how well they do compared to EPA range
| estimates; we're talking about the car choosing to put the EPA
| range estimate on the dash even when the car knows that number
| is bunk.
|
| Most ICE cars (and other electric cars) use driving history
| averages to adjust the range estimate on the dash, and a touch
| of pessimism. They're still not perfect, but better than
| claiming EPA range for someone who you know never gets close to
| it.
| postmeta wrote:
| Reuters' Steve Stecklow writing Tesla clickbait again in bad
| faith, range can change 10-30% based on how fast you go and
| weather: https://www.tesla.com/support/range
| Thoeu388 wrote:
| They also lied about C02 emissions. My country manufactures 30%
| of electricity from coal. That is hardly zero emissions!
| esotericimpl wrote:
| [dead]
| macintux wrote:
| Active discussion today here:
| https://news.ycombinator.com/item?id=36891642
| eagerpace wrote:
| Tesla owner, not saying they didn't do this, but to consider...
|
| The range in an EV is impacted by more variables than a gasoline
| vehicle. I've seen so many sensationalized headlines the last
| couple a weeks, in particular one about how the heat wave is
| killing electric cars.
|
| Look, as with any big change, people have to learn how the new
| thing works and that takes time. I don't get the same range on a
| 95 degree day as I do on a 75. The rain impacts it, charging my
| phones impacts it, running the AC impacts it. I believe the
| number provided in the vehicle is fairly accurate and considers a
| handful of factors. But others like your driving style also have
| a huge impact and there is no way to account for that.
|
| Can the software get better and incorporate more variables in its
| estimate? Yes. Do consumers also just assume the number displayed
| is perfect? Also yes.
|
| We had this same problem when GPS navigation became available.
| There were stories of people who followed the guidance before
| their common sense and ended up in strange places. Now we know to
| use it as a guide and check for common sense.
| interstice wrote:
| I find it funny that a side effect of ICE cars being so
| inefficient is that their range is much more predictable. If
| ~50% of your petrol turns into heat no matter what you do then
| using the AC doesn't make a lot of difference.
| ht85 wrote:
| I don't think they have to do with inefficiency.
|
| Predictability is there because combustion engines operate
| the same regardless of weather conditions.
|
| AC / energy consumption anxiety doesn't exist because of said
| predictability as well as your ability to refill 1000km worth
| of fuel in a couple minutes.
|
| The only difference if ICE were 100% efficient would be a
| slightly smaller gas tank.
| oxygen_crisis wrote:
| Favoring optimistic predictions isn't a reasonable response to
| large margins on complex probabilistic models. "Under-promise
| and over-deliver."
|
| Choosing the side of the margin that favors your marketing at
| the risk of stranding the customer on the side of the road is
| the unscrupulous choice.
| therouwboat wrote:
| Come on, tesla makes self driving cars and now they have
| trouble estimating range?
| PraetorianGourd wrote:
| If this is the case, why is Tesla the outlier? Ford, Hyundai,
| GM etc. all seem to be able to accurately estimate range. In
| fact, as the article mentions, Hyundai is slightly inaccurate
| in the opposite direction (though not by the same margin as
| Tesla over-estimates).
|
| If this is simply people getting used to a new technology,
| wouldn't it be a similar story across the board?
| retrocryptid wrote:
| Hunh. Tesla lies to it's customers. Who'd of thunk it?
| m463 wrote:
| All EVs have this problem.
|
| That said - drive conservatively and you can meet or exceed the
| predicted range.
| ericd wrote:
| Really depends, if I blitz along at 80, then yeah. If I stick to
| the speed limit, it's not a bad estimate, on mostly slow local
| roads, we get substantially better. It's a great demonstration of
| drag's nonlinear nature (the cube of the speed?).
| jstarfish wrote:
| > The National Maximum Speed Limit (NMSL) was a provision of
| the federal government of the United States 1974 Emergency
| Highway Energy Conservation Act that effectively prohibited
| speed limits higher than 55 miles per hour (89 km/h). It was
| drafted in response to oil price spikes and supply disruptions
| during the 1973 oil crisis and remained the law until 1995.
|
| I've always been under the impression 55 was the optimum speed
| for (ICE) fuel efficiency.
|
| Does this change at all for electrics (given regenerative
| braking)?
| olyjohn wrote:
| No it's a tradeoff between speed and efficiency. If you went
| 45mph, you'd get even better gas mileage. But people already
| couldn't drive 55.
| mirrorlake wrote:
| The best MPG you can get on the highway is just the slowest
| you can safely go without confusing other drivers, making
| people angry, or getting pulled over by the police. Drag is
| proportional to velocity squared, so every increase in mi/hr
| wastes more energy pushing air out of the way of the car.
|
| To answer your regenerative braking question: braking is
| inefficient by default, so just avoid tapping the brakes in
| situations where you could coast.
|
| With regenerative braking, you'll never get back 100% the
| energy because of thermodynamics. There's always wasted
| energy any time energy is moved, transformed, stored, etc.
| ht85 wrote:
| Modern cars with variable valve timing and other goodies can
| achieve very good combustion under low load. Looking around,
| it seems ~30km/h would be the sweet spot.
|
| It would be slightly higher if you run the AC on high,
| increasing total consumption by ~10% and moving the dial a
| bit.
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(page generated 2023-07-27 23:02 UTC)