Lower weight is better when you have to stop and go a lot, or have a lot of hills. But once you get moving, kinetic energy allows you to partially regain some of that invested energy. If you use a regenerative alternator to slow the car, then you can gain a little more.
Aerodynamic drag loss is *always* a *total* loss. It is about 50% of the total load at about 30-35mph, and it is 75% of the load at >65mph.
You may have missed the related part of my blog post:
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So the lowest MPGe of an electric drive; the AMP'd Sky was 86.7MPGe (Tango was 86.8), while the best of a car with an internal combustion is the Edison2 #97 at 101.4. (Actually, the FVT has a ICE powered generator onboard, but did not need it *at all* in the X-Prize. It would be great to see how the eVaro does for MPGe in charging mode!) The hybrids all were all below the 67MPGe -- except the WWU at 92.5 (and the FVT).
The average of the 12 vehicles using electric drive MPGe (I'm including the FVT in this) was 134.7MPGe
The average of the 6 hybrids (not including the FVT) was 61.26MPGe (Please note, these are all parallel hybrids?)
The average of the 5 internal combustion drive cars was 82.92MPGe
The X-Prize results table does not include weights, but I daresay that the average weight of the internal combustion cars was lowest (the Edison2 and Spira are all much lighter!).
The best aero drag is on the X-Tracer, followed by a very close group including the Aptera, Edison2, Li-ion.
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Those four critical things are; from most important to least important (as I am interpreting the Knockout results):
* Drivetrain Efficiency
* Aerodynamic Drag
* Weight
* Rolling Efficiency
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Now we have the Edison2 VLC Electric that with a DC drivetrain and about 220 additional pounds (830 vs 1040) -- and additional ~26%, the efficiency went from 110MPGe up to 245MPGe. They are looking at a AC drivetrain which should improve it another 20% at least.
Also, the 2,900 pound Illuminati Motor Works 7 gets 207MPGe on the EPA Combined test:
http://illuminatimotorworks.org/blog/?p=292
This is ~3.5X heavier and the aerodynamic drag is 0.23 vs 0.164 if I recall correctly. The drivetrain efficiency is at the top of the list.