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Which is worse: AC or windows down?

Discussion in 'Gen 2 Prius Fuel Economy' started by Mondrin, Jun 29, 2008.

  1. JimboK

    JimboK One owner, low mileage

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    Well, I guess you could say it accounts for it, but only to the extent that the simulator has two settings for climate control -- one for whether it's on and the other for the temperature setting. I'm guessing it assumes a "maintenance" mode of sorts for cabin temperature that has already reached the set point, and that it does not consider the initial burst required to cool a sun-baked cabin.

    I've thought about charting the current flow with AC in my own car, similar to how I've reported other operating parameters here. But knowing the inevitable MPG hit, I just can't bring myself to turn it on.;) Maybe I'll do it the next time m'lady's riding with me. She doesn't tolerate wind in her hair or hot air in her face. :p
     
  2. Jack66

    Jack66 Kinda Jovial Member

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    So do you stand behind her when talking? :D

    Sorry, Jim, couldn't resist!

    Have a great 4th of July
     
  3. JimboK

    JimboK One owner, low mileage

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    Safest thing is just to keep my mouth shut completely! That way I don't get hit and she doesn't get burned. :tape2::bolt:
     
  4. Jack66

    Jack66 Kinda Jovial Member

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    I've been putting the windows down for the first five minutes to cool the Mystery Machine down then turn the AC on to 75. I've been getting 53 MPG - normally I'm around 48.
     
  5. go4less

    go4less New Member

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    Windows vs A/C has been talked about for years---I have no plans to drive in hot days without air. But I will make sure as not to over cool. When I get my 2008 Prius in Aug I will follow a lot of the tips and try to get the best mpg that I can but within reason.
     
  6. PriusSport

    PriusSport senior member

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    Rather than opening windows, run your blower at high speed--forcing outside air through the vent system. Lower drag than open windows. You can also run your AC for short times with internal circulation, for quick cooldown. Then switch to outside air through the vents. Alternate as needed. The electronic controls are simple to manipulate.
     
  7. doubleg2005

    doubleg2005 Member

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    it's been consistently 95-100 here for this month (we had one cool day at 92, which was nice) with 70-90% humidity and i drive 45 mph with all four windows down and get about 60-65 mpg. with auto ACC at 78 that drops to about 50-55, which is, interestingly, close to what I get on the hwy at 62 mph with ACC on.

    the other day i did try rolling two windows up and also all four at half-way but there just wasn't enough air flow for me and the FE seemed to stay pretty steady compared to all four down... FWIW
     
  8. ctbering

    ctbering Rambling Man

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    I must be a completely self-absorbed human being oblivious to the Prius challenges to get MPG's during various weather conditions. In the summer, I open the windows when its nice outside or I set my air conditioning to 77 when its hot with the windows rolled up. If my dog is in the back seat she prefers her big head resting on the door with the back window completely open (drooling on the outside of the door). If we are on the highway all windows are up.
    MY MPG's are very good and if I have to sweat profusely to save on MPG's I think I would have to revaluate whether I should continue to subsidize my Caribou decaf vanilla coffee cooler habit.
     
  9. jammin012

    jammin012 The man behind The Man

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    Windows down is worse. You smell more of the crap outside and the air rushing through your cabin will take it's tollon your interior. AC on is the way to go.