EV (BMW i3) Acceleration Vs Efficiency: Faster is Better

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  • Опубликовано: 23 дек 2024

Комментарии • 29

  • @vernongomes
    @vernongomes Год назад +1

    I remember in the Prius hay day, this would be true, and it was called pulse and glide. Pulse to get to speed quick (but not too quick), and then coast by slightly being on the accelerator rnogih to not lose speed or gain speed.

    • @kalmmonke5037
      @kalmmonke5037 Год назад

      that is a different matter, that is about making combustion engine run at optimal work per energy used according to the bfsc chart for the specific engine

  • @ch0ch1s
    @ch0ch1s 7 месяцев назад

    I think this is related to rolling resistance. Remember at higher speeds the resistance is lower, si even if the wheela have to spin faster it needs less power to do so because rolling resistance is much lower.
    This is true until around 70kms/h. Then air resistance gets bigger exponentially.

  • @hawedehre
    @hawedehre Год назад

    I tried Intervall heating this winter and it seems to work. I put it on 28 C with full fan in ECO Mode and then switch it off for several minutes. Consumption seems lower to me than having it always on and comfort is ok for me.

    • @bmwi3diy782
      @bmwi3diy782  Год назад

      Nice suggestion to save range. I've also noticed that at least on short trips, having the heater on continuously is not necessary. Most of the time just using the seat heater is enough to be comfortable. Thanks for watching!

  • @hawedehre
    @hawedehre Год назад

    That’s interesting, I would have seen the idea as unlikely. Energy to keep it rolling at constant speed at a longer time seems beneficial.

  • @BillACK
    @BillACK Год назад +1

    Maybe a more accurate test would be to start with a full charge and see what range you get using hard acceleration for one charge and gentle for the next charge over the same route.

    • @michaelgourski3546
      @michaelgourski3546 Год назад +1

      Good idea Bill
      Lets do it

    • @abubakrakram6208
      @abubakrakram6208 Год назад

      I've done this with my i3 for about a year (since I owned it). I'd always get about 100-110 miles of range. For the first time I tried going easy and I got 130 miles. Bruh…

    • @bmwi3diy782
      @bmwi3diy782  Год назад

      Great suggestion! I'm not completely sure the gauges are telling me the truth either. Thanks for the feedback.

  • @tarassu
    @tarassu Год назад

    AFAIK most EV drivetrain efficiency graphs show that inverter and motor efficiencies are really high at motor speed 30-70% of motor maximum and at loads 30-60% of maximum motor torque (not power, torque). So it appears that 0-10 low load and at higher speeds about 50% of maximum power is more or less appropriate. In cold conditions, battery chemistry efficiency drops, so in cold weather, amps must be kept low, no more than 30% of maximum battery power.

  • @beforebefore
    @beforebefore Год назад

    The instrumentation speed is likely lagging the inverter output in order to filter out inconsistencies. This causes the energy meter to give lower than actual values during fast acceleration.
    In technical terms, everything works less efficient at high current, which is fast acceleration. The Inverter IGBT switching devices generate more heat, which is energy loss. The motor stator wire will also heat more, due to I2R losses. The HV battery will have higher losses due to internal impeadance of the cells. Every single electronic and electrical component in the drive system will be less efficient... there just is no escaping the facts.
    Regarding the Prius comparison, that's a parallel hybrid, where the gas engine has a direct connection to the drive wheels, so running the ICE at an elevated power level can force the hybrid controller to bypass charging the HV battery during moderate acceleration, which translates to higher efficiency usage of the gas engine during that time.
    As another commenter said, drive much longer distances, you may see more valid results - because the battery won't lie like instrumentation can.

    • @bmwi3diy782
      @bmwi3diy782  Год назад

      Yep- I agree with your points... which is why I was shocked at the results as well, and mentioned that the instrumentation may be giving a false response as you suggest, unless the engine efficiency IS really poor at low speeds. However, I think this was a good topic to share and get everyone's feedback! Thanks for the comments>

  • @RobotoForgoto
    @RobotoForgoto Год назад

    Physics is physics...do you think energy as heat is lost in the speed controller?

    • @bmwi3diy782
      @bmwi3diy782  Год назад

      It could be the the speed controller efficiency or motor efficiency at the lower rpm is an issue, or the data being collected by the board computer is inaccurate at the lower speeds. I agree that physics is physics!

  • @safari5412
    @safari5412 Год назад

    This is really surprising!
    The combined rolling resistance and air resistance must be greater in the test with strong acceleration!
    Incidentally, I noticed that the steering wheel in your i3 is black. Is this an accessory? I have an i3 with a white interior and a steering wheel which, unfortunately, looks somewhat worn. If you have a tip, I would be grateful.

    • @michaelgourski3546
      @michaelgourski3546 Год назад

      He was driving 20 ml/h What air resistance?

    • @bmwi3diy782
      @bmwi3diy782  Год назад

      Re steering wheel, I put a black cover on it 5 yrs ago to protect it, and also so stains from hand don't show as easily. Cost ~ $10 on Amazon at the time. Thanks for watching!

  • @CarlosChaconCR
    @CarlosChaconCR Год назад

    Very interesting, and driving the i3 is-so-easy get used to drive fast which can result in better performance. 😉

    • @kalmmonke5037
      @kalmmonke5037 Год назад

      this is probably a issue specific to this car, because of the type of motor being used. tesla semitruck uses 2 different motors for high speed and low speed, for optinal effiency. maybe this car only used 1 type because the cost of two in terms of effeincy in averager type of use would make such complexity less effceint overall

  • @GP-SEA
    @GP-SEA Год назад

    I'm thinking the test is a little too short to be accurate. I doubt a BMW engineer considered this sort of test scenario!

  • @tw1919
    @tw1919 Год назад

    Maybe fast starts gives more regen later

  • @Crono454
    @Crono454 Год назад

    I was under the impression that it was a known difference of electric vehicles that the motor is under more load to maintain speed than ICE vehicles. So unlike ICE, maintaining speed is comparatively costly for BEV, and conversely stop and go is better for BEV.

    • @bmwi3diy782
      @bmwi3diy782  Год назад +1

      To maintain a certain speed, it is true that most drive trains on ICE vehicles are the most efficient at ~40-60mph by design (higher gear ratios, most efficient load/rpm of the engine). Most other factors such as tire rolling resistance, may be slightly worse for an EV due to extra battery weight (especially on newer models with huge battery packs), but drag from air resistance is by far the dominant impact for both EV's and ICE vehicles. I think the issue is that even at the 'sweet spot' for an ICE vehicle, the efficiency will still be way less (in terms of MPG equivalent or energy per mi) as compared to a typical EV. Both ICE and BEV's are less efficient at very low speeds, it turns out, mainly from drivetrain inefficiencies and auxiliary component power drain rates per mile. BEV's are more efficient at stop/go due to regen, and better torque at low speeds, but a good hybrid could be in the same ballpark. Great question/comment, maybe other viewers have more insight on this...

    • @Crono454
      @Crono454 Год назад

      @@bmwi3diy782 great answer and great content 🙌

  • @michaelgourski3546
    @michaelgourski3546 Год назад +2

    It’s surprising, however in long run you are saving few bucks on electricity, and loosing hundreds on tires

    • @kalmmonke5037
      @kalmmonke5037 Год назад

      microplastics coming off the wearing of tire from friction, is argueably worse than emissions form combiustion. supposedly, brakes wear is also same story except for ceramic brakes.

    • @smk6469
      @smk6469 Год назад

      ​@@kalmmonke5037 There's no PFAS going into your bloodstream from fast EVs... Goddamn.

    • @kalmmonke5037
      @kalmmonke5037 Год назад

      @@smk6469 water supply food supply , plants animals. they dont even fitler out flouride and endrocrine disrutir in water supply isnt filtered. and in microplastics were talking micro level stuff. so called "forever chemcials"