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EV %, mi/kwh, avg speed

Discussion in 'Prime Fuel Economy & EV Range' started by crewdog, Jan 31, 2017.

  1. Trollbait

    Trollbait It's a D&D thing

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    You used MPGe values with efficiency. In what way does this efficiency differ from consumption rate? The MPGe rating would account for all those things(mass, aero, etc.) you attribute to consumption rate.

    The weight difference alone could account for a 5% difference in fuel efficiency.
    The gen2 Volt's electric side does see efficiency improvements, but there was also focus of cutting weight, size, and cost.

    The two MGs are the same physical size, and their power ratings are close(finding separate MG A and B specs is about as easy finding MG 1 and 2 ones for the Prius), but one uses a ferrous magnet instead of the typical rare earth one in the other and normally used by other hybrids and plug ins. The two motors' roles aren't as delineated as in the Prime with them being close in size and power. When one motor is only needed, it could be either one.
     
  2. martydallas

    martydallas Member

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    with the Prime at 133 MEPe and the Tesla at 89-101 depending on the model. I use this to make my dections to weather to use my elect. or to use gas. BUT :) if I can use FREE elect from whole foods as I do most days at work that is a no brainier for me
     
  3. EV-ish

    EV-ish Active Member

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    Perhaps in the old ICE only days, but not when regen recovers 30-50%

    I'll try to clarify, since my conclusions are somewhat subjective. I attribute to efficiency those factors that within the control of the manufacturers. For examples:

    A motor with a better power curve and less losses for the same outputs
    Weight reduction not related to size reduction
    Cd reduction that does not detract from function

    Versus, for example:
    A bigger car that all else being equal, will weigh more and have more air and road friction.


    A good example is the original Honda Insight. Its very enviable consumption rate was a mixture of small size and crappy tires (anybody can do that), light weight from Alu use (expensive and difficult for the times choice), and impressive Aero design.

    You are right that I used MPGe to calculate efficiency differences and this is sloppy, but as I mentioned, I have been too lazy to try and separate out the individual contributions. It is also true that from my POV if two cars are in the same class and would fill my requirements equally I tend to look at consumption rates as a bottom line. I'm a little ashamed to have joined the ranks of the illiterati and lazy by writing efficiency when I should write consumption rate. Of course, if I do most people will wonder why I am being obscure.
     
    #43 EV-ish, Apr 6, 2017
    Last edited: Apr 6, 2017