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Originally Posted by byte312
Ok I think that you are correct. But is it fair to say that drag will increase with added weight? The kenetic energy is x2 for twice the weight but now add the increased drag from the tires being pressed into the pavement and the bearing friction then figure in the reduced effeciency of the motor as it passes more current almost like a straight piece of wire under heavy load. This is what will rapidly discharge your batteries.
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The aerodynamic drag will be mostly unchanged with higher weight. The rolling resistance and drivetrain losses increase, but not 2x. The impact on range will be very, very dependent on the drive cycle. Driving on a level highway is dominated by aerodynamic drag and speed-dependent drivetrain losses, with almost no dependence on weight. Driving in stop-and-go traffic or on hills is dominated by the vehicle weight.
Quote:
Originally Posted by byte312
regeneration of 25% to 30% is fantastic. If you can get that much energy back, your range will be 25 to 30% better.
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No. No it won't. That's energy recovery, not the increase in range. Especially if you use the optimistic definition of range "how fan could I possibly get at constant speed on a level highway". Regeneration adds 0 to that 'range'.
On a realistic drive cycle, regeneration will improve the efficiency 5-15%. Again, heavily dependent on the details of the drive cycle. Yes, it's free energy. But it's grossly oversold as a benefit.
Quote:
Originally Posted by byte312
The most practical cars do not have a full transmission, CV joints, and differential.
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Practical cars have all of those. Tesla only skipped the transmission because they couldn't get their initial design to work. (Pretty much they ended up with a one speed transmission as an interim substitute.) You can only omit the differential with multiple motors, which is uncommon. And to get rid of the CV joints you need hub motors, with an unworkable increase in unsprung weight.