Windows/AC NOT affect MPG - Fuelly Forums

Android Users - Coming Soon! - Migrating from aCar 4.8 to 5.0

Reply
 
Thread Tools Display Modes
 
Old 05-16-2007, 12:48 PM   #1
Registered Member
 
Join Date: Dec 2006
Posts: 39
Country: United States
Windows/AC NOT affect MPG

Browsing around on-line and came across this, thought some poeple would like to read it and see what the big bussinesses think. here is the link to the full article.
http://biz.yahoo.com/cnnm/070515/050...pf=family-home


"Windows, air conditioning - who cares?

There's the old saw that leaving your windows rolled down creates an aerodynamic drag on your car, cutting down on fuel efficiency. And there's the notion that the fastest way to drain your gas tank is by running your air conditioning.

Don't believe either one.

In two separate studies conducted in 2005, the automotive Web site Edmunds.com and Consumer Reports compared the fuel economy of both a sedan and an SUV at highway speeds with and without air conditioning and how open windows affected gas usage.

What they found was no significant difference in fuel economy in either sedan or SUV under either condition.""
__________________

__________________
Zvolen is offline   Reply With Quote
Old 05-16-2007, 12:53 PM   #2
*shrug*
 
Join Date: Sep 2005
Posts: 6,195
Country: United States
This was actually mentioned in another thread. The main issue is "significant." Some people here have done their own tests with their scanguage, and the drop is usually quite dramatic (at least by my standards).

I fancy this article is a bit misleading...
__________________

SVOboy is offline   Reply With Quote
Old 05-16-2007, 01:07 PM   #3
Registered Member
 
omgwtfbyobbq's Avatar
 
Join Date: Jul 2006
Posts: 1,516
Country: United States
Yup... What SVOboy said. Heck, I bet most Americans wouldn't consider a 10mpg difference in fuel economy "significant" judging by how they drive.
__________________
Quote:
Originally Posted by FormulaTwo
I think if i could get that type of FE i would have no problem driving a dildo shaped car.
omgwtfbyobbq is offline   Reply With Quote
Old 05-16-2007, 03:15 PM   #4
Registered Member
 
Join Date: Mar 2007
Posts: 1,138
Country: United States
Yeah, most people get about 20 mpg, and can't see a 2 mpg change, so burning 10% more or less gasoline is not significant to them.
__________________
Bill in Houston is offline   Reply With Quote
Old 05-16-2007, 03:32 PM   #5
Registered Member
 
JanGeo's Avatar
 
Join Date: Jan 2006
Posts: 2,442
Country: United States
Send a message via Yahoo to JanGeo
yeah exactly - NOTE the test was Sedan and SUV not an economy car!
JanGeo is offline   Reply With Quote
Old 05-16-2007, 03:46 PM   #6
Registered Member
 
Join Date: Dec 2006
Posts: 39
Country: United States
First off sorry if this was already mentioned.

It was my belief too that the article is a bit misleading on what it mentioned and did not mention. For instance no mention of general tune up and keeping your car in good shape but promoted turning your car off. Kind of ironic how the general public views these issues.

They also didn't mention some details about the "test" average speed and vehicle type. A significant gain to me surely would not be the same to the general public who on average get 20MPG or less in a SUV.

Oh well, interesting to say the least.
__________________
Zvolen is offline   Reply With Quote
Old 05-16-2007, 04:01 PM   #7
Senior Member
 
CoyoteX's Avatar
 
Join Date: Dec 2012
Posts: 230
Country: United States
Location: Southern WV
In my Camaro there is no difference at all running the air conditioner on the highway with the windows rolled up. Windows down and T-tops out I get 2-4mpg less depending on the speed. Most of that is from the t-tops being out.

I think anything with 8 cyl is not going to show as much change due to a/c running. Especially considering most engines are cammed for power so they are not really running that efficiently. I would like to see someone do a test comparing mpg vs speed for windows up no a/c, a/c on low/normal speed, and windows down. I would figure there is a speed that a/c will be better than windows down and it is probably around 60mph for most cars.
CoyoteX is offline   Reply With Quote
Old 05-16-2007, 06:08 PM   #8
Registered Member
 
JanGeo's Avatar
 
Join Date: Jan 2006
Posts: 2,442
Country: United States
Send a message via Yahoo to JanGeo
I would say that it is the speed at which the noise level starts getting really loud would be when the losses start getting greater and then you can always roll them up a bit.
JanGeo is offline   Reply With Quote
Old 05-16-2007, 06:50 PM   #9
Registered Member
 
Join Date: Apr 2007
Posts: 79
Country: United States
Engine size definitely comes into play. If you're familiar with a/c compressors and systems, you'll notice that the a/c compressor and pulley are about the same size regardless of the engine size.

At idle, most small engines increase the rpms by at least 75%. In my Jeep, I have the I6 4L motor and there's barely an increase in rpm at idle.

Highway driving is a completely different beast than city driving. You're not accelerating nearly as much. Acceleration and a/c don't get along in economy cars.


You can't throw a generalization like that on transportation (or anything else for that matter).
__________________
I see no reason why fuel economy and power cannot coexist.
DrivenByNothing is offline   Reply With Quote
Old 05-16-2007, 07:38 PM   #10
Registered Member
 
GasSavers_Randy's Avatar
 
Join Date: Apr 2006
Posts: 98
Country: United States
Farther down the story they say cruise control nets you 7%! Edmunds and Consumer Reports drive like most people drive, so they get bad mileage all around, and report it as such.

What's true for them is true for most, but may not be true for the serious mileage driver.
__________________

GasSavers_Randy is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Not very precise mpg calculation larjerr Fuelly Web Support and Community News 4 08-20-2012 02:03 AM
Who's mileage is the worst? Mike1nyny General Fuel Topics 10 11-03-2009 11:03 PM
Keeping my distance in traffic khurt General Fuel Topics 8 09-07-2008 04:23 AM
Electrical power and cars. DracoFelis Automotive News, Articles and Products 2 09-16-2006 02:31 PM
"active" aero grille slats on 06 civic concept MetroMPG General Fuel Topics 21 01-03-2006 01:02 PM

Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 04:31 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.