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Windows Up & AC On vs Windows Down - can the Leaf test this?

Posted: Fri Feb 25, 2011 11:18 am
by JasonT
I'm sure you're all familiar with the debate over which is better - driving with the windows up and the AC on, or the windows down and the AC off. My understanding is that it really depends on the car, the speed, and the conditions.

I was wondering if the instrumentation on the Leaf is precise enough that one could test this on their own without any additional gadgets. The thought I had was this: Find a flat, straight stretch of road that you can go whatever range of speeds you want to test. Set the cruise control to a speed and run whichever test you want to run (Windows Up, Windows Up AC On, Windows Down). Go back to the beginning of the stretch, and repeat for the other tests. You could then go down or up in speeds for additional data points.

I see that the Energy Usage screen does give the current (hah) kW draw, but the information is given in an "analog" format instead of a straight digital display. This makes it trickier, but I would imagine one could still get a good idea of what their windows up/down point was.

So would this work? Is the information given to the driver granular enough for this test to work? Would the instant miles/kWh gauge work better for this? I am (hopefully) getting my car in April, but until then I have to rely on the kindness of strangers for these kind of things :)

Re: Windows Up & AC On vs Windows Down - can the Leaf test this?

Posted: Fri Feb 25, 2011 11:29 am
by abasile
Sounds like a good idea for my son's science fair project. Yet another reason for my wife to let me buy the LEAF, so that my older son and I can conduct "experiments" together. :lol:

Re: Windows Up & AC On vs Windows Down - can the Leaf test this?

Posted: Fri Feb 25, 2011 11:38 am
by GeekEV
The Mythbusters tested this in one of their episodes and revisited it the next season. Not a LEAF (obviously), but in general the same concept should apply.

http://en.wikipedia.org/wiki/MythBusters_(season_2)#AC_vs._Windows_Down
http://en.wikipedia.org/wiki/MythBusters_(2005_season)#AC_vs._Windows_Down

I'd be willing to give it a shot, but it's too cold right now!

Re: Windows Up & AC On vs Windows Down - can the Leaf test this?

Posted: Fri Feb 25, 2011 12:58 pm
by JasonT
abasile wrote:Yet another reason for my wife to let me buy the LEAF, so that my older son and I can conduct "experiments" together. :lol:
Hah, yeah, good luck on that one. "Honey, we need to spend $35,000... FOR SCIENCE!"

GeekEV wrote:The Mythbusters tested this in one of their episodes and revisited it the next season.
Yeah, I remember watching one (or both) of those episodes. It's been done by numerous people I'm sure - another one was The Straight Dope

Being that I currently have a convertible which has the top down about 95% of the year, I'm very curious what my "windows down" spot will be. I've gotten the impression it's around 45/50MPH in most vehicles, but I would love to know it instead of just guessing. Plus, it just sounds like a fun thing to try :-)

Re: Windows Up & AC On vs Windows Down - can the Leaf test this?

Posted: Fri Feb 25, 2011 1:11 pm
by Gonewild
Well if I had to guess
I would say for the LEAF the use of AC will use more power then the air drag will cause the engine to draw more.
What ya think?

Re: Windows Up & AC On vs Windows Down - can the Leaf test this?

Posted: Fri Feb 25, 2011 2:13 pm
by DaveinOlyWA
Done plenty of both and the #1 factor by far; driver preference.

I don't care what is more efficient. Some days I just want the wind in my hair

Re: Windows Up & AC On vs Windows Down - can the Leaf test this?

Posted: Fri Feb 25, 2011 4:02 pm
by EVDRIVER
If the LEAF had a proper KW meter you could test this but it does not.

Re: Windows Up & AC On vs Windows Down - can the Leaf test this?

Posted: Fri Feb 25, 2011 10:45 pm
by garygid
Please, remind me what is wrong with the LEAF's kW meters?

Is it that there are three instead of one for total kW?