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Old 11-29-2010, 12:46 AM   #19 (permalink)
tumnasgt
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Location: Wellington, NZ
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The Charger - '15 BMW i3
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Quote:
Originally Posted by 04_Sentra View Post
I checked it out in gph instead of mpg though since the headlight load is going to be constant, the same at idle as at highway speed. Once the car was completely warmed up I was using 0.2 gph at idle and when the headlights turned on it went to 0.23 gph.
I don't think the difference will be constant, as at different loads/RPMs the engine changes efficiency (idle being pretty bad). It would be interesting to see how much different loads/RPMs change the effect.


Also, for electric load tests (as the fuel consumption change should be similar between vehicles), it makes sense to use gallons/100miles or similar, as a 3MPG loss on a 100MPG car is only 0.03 gallons wasted per 100miles, where as on a 15MPG pickup it's 1.67 gallons wasted per 100 miles. Percentages are also off for a test like this because x% of a pickup's fuel consumption is much greater than x% of a hybrid's fuel consumption.
I don't want to start a unit war, it's just food for thought.
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