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Discussion Starter #1
For the current Cdn. tests showing 4.5 L/100km & 4.7 L/100km respectively
I would expect hwy results to only improve marginally, since Jpn site shows engine about 5% of the 100% increase in energy efficiency.

The other contributions are (approx.):
Regeneration 33%
Control 25%
Accessories 12%
Electrical 10%
Transaxle 10%
Other 5%

Am I getting this right? This refers to tank to wheel efficiency improvement from 32 to 37 in domestic Jpn after improvements introduced there.
http://www.toyota.co.jp/IRweb/special_r ... s2_10.html
 

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Discussion Starter #2
This Hwy figure from Canada eqates to 50.8 mpg, and as I said, if cruising at say a constant 3,400 rpm's, why would this increase much when only 5% of the 100% increase in efficiency comes from the engine improvements.

It is also interesting that the System Controls mean the generator
dials in the RPM's of the engine such that at much lower speeds, the engine becomes more fuel efficient, and delivers max. power. (Of coarse it is the computer that tells the Generator what to do. And if the electrical air conditioner is turned on, RPM's of all three (engine and two motors) can be varied).
 

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For highway driving there is no improvement to expect from regeneration, since it is extremely marginal at approximately constant speed. The only benefits can come from the thermal engine efficiency... and from the drag coefficient of course, which is significantly better on Prius II. Don't forget a car is basicly using energy for pressing on the air during highway driving ! From 0.29 to 0.26 means 10% improvement, although you must also take into account the projected area of the car, which could be a little larger (I don't have any data for the new Prius).
 
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