11 ms·

Battery meter at the top is EPA range - ie. the official range measurement method, in basically ideal conditions. The routefinder 'learns' from your previous d

• lotsofpulp 3y ago
  I thought braking aggressively increases range.
  • jackmott42 3y ago
    if you brake too aggressively then you will use brake pads as well as regen, and that wastes energy. Also, its still better to arrange to not need to brake at all, than to regen, since regen is not 100% efficient.
  • goshx 3y ago
    Not if you use the break pedal
  • tialaramex 3y ago
    No? Accelerating and decelerating are both lossy, and for the brief intervals when you're going faster you're also taking additional wind friction loss. Most EVs (including Tesla) do have regenerative braking, so some of your energy is converted back into electricity when you brake, but nowhere close to all of it, so people who have a smoother, less aggressive profile will get more range. Also if you brake really aggressively, you're dissipating more energy than can be successfully harvested and the rest is converted to heat, losing the energy you paid for and also increasing maintenance costs.
    • lotsofpulp 3y ago
      I see, thanks for explaining!
  • b0sk 3y ago
    Braking doesn't increase range. Rather the natural foot off pedal regen braking increases range. If you physically slam on brakes, I'm sure that doesn't help range.
    • martin8412 3y ago
      That's a Tesla problem. They couldn't figure out blended braking. If I press the brake hard in my car, the regen goes to max possible.
      • mint2 3y ago
        That is an accurate meter, it is not a Tesla problem. My PHEV works the same way, but that fact isn’t really relevant. The meter is presenting you the regeneration “rate” but what you’re thinking of is the regen rate integrated over time, I.e the amount of charge recovered during the process of stopping, which the meter is not showing you.
        • martin8412 3y ago
          Maybe, I don't really care about regenerative rate, I just notice my meter going to max when braking hard. I only use the battery for city driving and hard acceleration on the motorway anyway. It's great for merging onto the Spanish motorways.
          • mint2 3y ago
            But the comment showed you do care, you brought it up and pay attention to it. It’s all that the meter shows that you mentioned.
      • sib 3y ago
        I'm sure that if you "slam on the brakes" (per GP), your car will take region to the max and the apply the real friction brakes, causing lots of kinetic energy to be converted to heat and "wasting" energy... (Also, Tesla cars do have blended braking between region & friction...)
  • 0xfae 3y ago
    What? How did you arrive at that conclusion. Even if the laws of thermodynamics and entropy took a holiday, and you recovered 100% of the energy when you brake, at best you would break even and not hurt your range (vs not braking aggressively). Regen breaking increases range over no regen braking, but braking aggressively will always be worse than not braking aggressively.
  • _jal 3y ago
    Yep. That's why I just leave a brick on the brake pedal. Infinite range!
  • idlewords 3y ago
    You can also recharge the battery by going in reverse, a solution I'm baffled more people don't know about.
• jncfhnb 3y ago
  When you say “learns” is it actually factoring in the route or is it just using the historical average miles per… what, kWh, and multiplying it across the distance
  • londons_explore 3y ago
    Haven't seen the code, so I don't know how it works. It certainly looks at the route though, because different destinations both 100 miles away give different estimated power usages.
  • stetrain 3y ago
    When you use the navigation system in a Tesla, the estimated energy usage for that trip takes into account the specific route, your projected speed, elevation changes, traffic, temperature, wind, and adjusts based on what speeds you actually end up going.
• jackmott42 3y ago
  EPA range is a mix of city and highway range. City range is > highway range, thus EPA range will over estimate highway range and underestimate city range.
• cowsandmilk 3y ago
  No reason it has to show the EPA range. My family’s Subaru has “learned” that it lives in the mountains and the range estimates reflect that. And I’m pretty sure it’s a simply looking at what kind of gas mileage it got recently. When we have kayaks on top of the car, it readjusts the mileage estimates down pretty quickly. All these comments about ICE vehicles being the same ignore that when ICE vehicles have estimates to empty, they take basic steps to try to get the estimate correct.
  • deleted 3y ago
    [deleted]
  • ComputerGuru 3y ago
    Same with my VW.
  • mulmen 3y ago
    My BMW even calculates "alternates". When I have under 50 miles of range it checks the internal (no Internet service needed) database and offers a route to the nearest known gas station.
  • patd 3y ago
    With your system, if I live somewhere flat and I go to the mountains, I will be out of juice during the climb. Tesla has a battery indicator in percentage and the navigation which is pretty accurate. Your ICE car has a gauge for the tank and an estimation of range. Tesla should probably not allow you to show the battery as range as it will always be inaccurate and people will complain. But if they only show percentages, people complain as well.
• cmrdporcupine 3y ago
  "Battery meter at the top is EPA range - ie. the official range measurement method, in basically ideal conditions." I guess I'm flabbergasted by this, as that's not how my Chevy Volt (and I presume many other BEVs) work. The range value ('guessimeter' people call it) on my Volt takes something like a rolling average of your last few drives and that's what it shows you. So if it's winter, it shows you less range because your last few drives had less efficiency. It's not always accurate (if there's, say, major temp fluctuations), but it's way more useful than what you're describing. To me, what you're describing is borderline dishonest marketing, and technically unnecessary. What I'd like to see is two numbers: estimated range as I've described, and beside it a kWh # (which I can guesstimate from the battery % gauge visual, but not precise). EDIT: Not sure why car manufacturers in general hide the kWh remaining-capacity of the battery so much. They seem to think consumers are too stupid to understand such technical terms? But they're clearly aware of it every time they use a public charger, and it's the closest equivalent to litres/gallons in an ICE.
  • stetrain 3y ago
    Tesla has the guess-o-meter based on recent driving, it’s just on a separate Energy page. I leave the dashboard meter set to percent because the “miles” option is just the dumb EPA rated range mapped to percent anyway. The real way to predict range in a Tesla is to use the nav system which takes many factors into account and has been very accurate in my experience.
• Merad 3y ago
  There's no reason why Tesla can't calculate the accurate range in both places, is there? My 2022 Toyota RAV4 Hybrid has a "distance to empty" number that "learns" based on your driving habits and typical mileage. It's not perfect, for example going on a road trip can throw it off (the hybrid gets significantly lower highway MPG than around town), but most of the time it's very accurate.
  • cmrdporcupine 3y ago
    Yeah, there's no reason they couldn't do that, and most other BEVs do that. The fact that Tesla doesn't is I'd say, disappointing? and likely to give EVs a bad name in the long run. But could also reflect that this is a California company where they don't really have weather.
    • ldbooth 3y ago
      Drive from from Sacramento to Tahoe in the winter... There's weather, and tons of ice/snow at elevation. Many here complain about how inaccurate Tesla's range calcs are driving to Tahoe. It's not the state, it's the amoral response to incentives.
  • stetrain 3y ago
    They do have a range estimate based on recent driving, it’s just in a separate Energy page. “Accurate range” is difficult. It could be accurate based on recent driving, but that number could be very inaccurate if there is a change in weather or you are taking a different kind of drive than your last one.
    • steveBK123 3y ago
      Probably showing range in 3 different places that don't really agree is bad right? We are HN tech crowd here so its all fun & games hobbyist stuff. But normies do not want to get into these types of inane subtleties. Arguably the front & center, always-there range display should be the most accurate, not the least accurate.
• cevn 3y ago
  It really does not learn. I have driven the same route to and from Richmond, VA as a range test over and over again since 2018. My range is approx. 180 miles, in favorable conditions (summer, AC off). If it was actually accurate, as soon as you hit 70-80mph you would see your range half. Clearly that doesn't happen, so the estimator is off by ~40% for highway conditions, i.e. complete bullshit.
  • stetrain 3y ago
    Are you talking about the battery meter? That is just EPA range * battery percentage. The precise estimate is in the navigation system, when you navigate to a destination and it says you will arrive with X% left. This takes into account speed, traffic, elevation, temperature, wind, etc. and is usually pretty accurate for me.
    • cevn 3y ago
      Ah I see. I will check on that but you would think that as soon as you get on the highway that estimator would change. It is also the first place someone would look for range, not inside navigation so I would call that false advertising…
      • stetrain 3y ago
        I leave the battery meter set to percentage, the “miles” option is really just percentage dumbly mapped to miles. The golden number in a Tesla Is absolutely the navigation route estimate. While navigating you can open the Energy app as well to see more detail, how you are doing compared to the estimate, and specific factors affecting consumption.
        • cevn 3y ago
          I also use percentage. It's not something that I usually think about. I just know that my "real range" is 180 miles at highway speeds. That's not something they tell you when you buy a Tesla. I also just don't use navigation if I've been somewhere more than once. Just navigate with my head..
• nicpottier 3y ago
  I think it's basically some PM taking a stand at Tesla with the fact that there's just no good estimate possible without knowing the route, so they will always show EPA estimate. Any sane a Tesla driver changes that to show percent battery instead of range. As others have said the trip planner is excellent, within a percent or two even in winter conditions driving over passes etc.. Note that range changes a lot more due to elevation, speed, cold etc, compared to gas cars because electrics are so much more efficient.
  • blake929 3y ago
    The article says it was a mandate from Elon Musk. Not sure I believe the claim, but I'd also be surprised if he wasn't aware just how optimistic the EPA estimate is.
  • bumby 3y ago
    My initial thought is that it's a mitigation to litigation. Maybe the thought was as long as you show the "legal" mileage calculation, you can't be held responsible for anything bad that happens? I don't think we apply that to ICE but I could see where a lawyer thinks it's necessary.
    • moduspol 3y ago
      I think you need to give consumers some vague idea of how much range you'll get in the car, and EPA-rated miles is at least a clear standard by which all EVs can be compared. A percentage indicator is fine for a car you already have, but not useful for comparing between cars. It could show kWh, but that isn't good, either. What consumers actually care about is range, and whether that comes from more kWh, better aerodynamics, or a lighter car, the range is the bottom-line number. We wouldn't want consumers buying a car with a bigger battery just because it has more kWh if it doesn't get better range. I think EPA-rated miles is the best of available options--it just needs to be understood by consumers. And I think cases where it isn't are a bit overstated. I suspect very few consumers genuinely believe they'll get the same range in miles regardless of their driving speed, headwinds, or whether they're going uphill or downhill.
• darth_avocado 3y ago
  I have a model 3. I recently took a trip of 196 miles but lost almost 270 miles in battery. I wasn’t driving like a maniac, I was on 65 mph cruise control the entire time with no traffic.
  • mint2 3y ago
    How were the Tires inflated? are they stock tires? are the rims the aero dynamic ones? were you using climate control, was their wind? Hills? Any roof cargo? All these have a big effects. Wind can easy be a 3mpg hit for my car, that’s about 10%. Not all the difference but a couple stacked effects could get yours Annoying all these things matter when range is constrained. Next gen batteries can’t come soon enough.
    • itsoktocry 3y ago
      >How were the Tires inflated? are they stock tires? are the rims the aero dynamic ones? were you using climate control, was their wind? Hills? Any roof cargo? All these have a big effects. True. But none of this should matter if your Tesla actually "learns", as other comments claim, right?
• itsoktocry 3y ago
  >The routefinder 'learns' from your previous driving habits. I'd like to see evidence of this, but I'm skeptical. Sounds like something Tesla fans claim is happening, like when you report an error at an intersection it gets fixed manually. And, even if true, I'm not sure how useful it'd be.