Go Back   EcoModder Forum > EcoModding > Hypermiling / EcoDriver's Ed
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 06-22-2008, 09:12 AM   #1 (permalink)
Here, there, everywhere
 
regor's Avatar
 
Join Date: May 2008
Location: San Diego County
Posts: 52

regor's civic - '08 honda civic lx
90 day: 39.95 mpg (US)
Thanks: 0
Thanked 0 Times in 0 Posts
AC on the entire time and I got my best MPG average ever??

As you all probably know, southern California is having lots of heat. I found myself using my AC more and more last week. Normally, I will drive home with my windows up, with no AC or the fan. Like many, I’ve been under the impression that driving with the AC on will drop for MPG, however, this last week, with my AC running the entire 40.5 mile drive home, I’ve averaged by best MPG ever with my same driving habits. Can anyone explain why my MPG did not decrease with the AC blowing?

Thanks

__________________
I drive-
11 Hyundai Elantra GLS
16 Honda Pilot LX
And a 1907 Baldwin Steam Locomotive (Really)
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 06-22-2008, 09:15 AM   #2 (permalink)
Administrator
 
Daox's Avatar
 
Join Date: Dec 2007
Location: Germantown, WI
Posts: 11,159

CM400E - '81 Honda CM400E
90 day: 51.49 mpg (US)

Daox's Grey Prius - '04 Toyota Prius
Team Toyota
90 day: 49.53 mpg (US)

Daox's Insight - '00 Honda Insight
90 day: 64.33 mpg (US)

Swarthy - '14 Mitsubishi Mirage DE
Mitsubishi
90 day: 56.69 mpg (US)
Thanks: 2,459
Thanked 2,530 Times in 1,526 Posts
That just means your car is capable of that much better mileage, seriously.
__________________
Current project: A better alternator delete
  Reply With Quote
Old 06-22-2008, 09:30 AM   #3 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 7,880

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 42.48 mpg (US)

Forest - '15 Nissan Leaf S
Team Nissan
90 day: 156.46 mpg (US)

Number 7 - '15 VW e-Golf SEL
TEAM VW AUDI Group
90 day: 155.81 mpg (US)
Thanks: 3,395
Thanked 2,896 Times in 1,817 Posts
Hello,

What it could indicate is that your A/C is more efficient than running with your windows down? Or, that your driving technique is much better now, and your mileage could be even higher if you could run w/o A/C?
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 06-22-2008, 10:25 AM   #4 (permalink)
EcoModding Apprentice
 
Join Date: May 2008
Location: South Dakota
Posts: 117

GMC Sonoma - '94 GMC Sonoma
90 day: 36.97 mpg (US)
Thanks: 0
Thanked 4 Times in 4 Posts
My explanation is that you need to do multiple tests, not knowing how you calculated your MPG.

The AC requires energy input so it cannot increase your mileage. It has to decrease it, all other conditions being the same.

It is very common to get different mileage on two different tank fills even though you think conditions and your driving was the same on each. The fact is, conditions can vary considerably due to a large number of factors beyond our control.
  Reply With Quote
Old 06-22-2008, 11:46 AM   #5 (permalink)
is awesome
 
Join Date: Apr 2008
Location: Kansas City
Posts: 56
Thanks: 0
Thanked 0 Times in 0 Posts
I've found over the past few years that if I use air conditioning on the lowest setting, which is plenty cold, the effect it has on mileage is negligible.
__________________
KU School of Engineering
'72 Datsun 240z
'96 Chevy lumina
  Reply With Quote
Old 06-22-2008, 01:01 PM   #6 (permalink)
Pokémoderator
 
cfg83's Avatar
 
Join Date: Dec 2007
Location: Southern California
Posts: 5,864

1999 Saturn SW2 - '99 Saturn SW2 Wagon
Team Saturn
90 day: 40.49 mpg (US)
Thanks: 439
Thanked 528 Times in 355 Posts
regor -

Maybe it's the effect of the hot dry temps. Now that summer is in full swing, these are the best times for MPG.

It is possible that *without* AC, you would have seen even higher MPG.

I just recorded my all-time best "go home" commute segment last Friday. I attribute it to Hot Dry weather and slower average speed.

CarloSW2
__________________

What's your EPA MPG? Go Here and find out!
American Solar Energy Society
  Reply With Quote
Old 06-22-2008, 01:16 PM   #7 (permalink)
EcoModding Apprentice
 
Join Date: May 2008
Location: Ohio
Posts: 107

Silver EP3 - '02 Honda Civic Si
Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by regor View Post
As you all probably know, southern California is having lots of heat. I found myself using my AC more and more last week. Normally, I will drive home with my windows up, with no AC or the fan. Like many, I’ve been under the impression that driving with the AC on will drop for MPG, however, this last week, with my AC running the entire 40.5 mile drive home, I’ve averaged by best MPG ever with my same driving habits. Can anyone explain why my MPG did not decrease with the AC blowing?

Thanks
MPG goes up with temps. Apparently yours went up enough to offset the small amount used by running the AC. Maybe you were also driving more? There are many things that effect mileage, as I have learned watching my ScanGauge II.
If you can try and get one of those, you will see!
  Reply With Quote
Old 06-22-2008, 01:21 PM   #8 (permalink)
Pokémoderator
 
cfg83's Avatar
 
Join Date: Dec 2007
Location: Southern California
Posts: 5,864

1999 Saturn SW2 - '99 Saturn SW2 Wagon
Team Saturn
90 day: 40.49 mpg (US)
Thanks: 439
Thanked 528 Times in 355 Posts
slurp812 -

Quote:
Originally Posted by slurp812 View Post
MPG goes up with temps. Apparently yours went up enough to offset the small amount used by running the AC. Maybe you were also driving more? There are many things that effect mileage, as I have learned watching my ScanGauge II.
If you can try and get one of those, you will see!
That reminds me. Whenever I have a "best run" for one of my trip logs, I save the weather from weather.com. I usually average the weather at the begin/end ZIP codes (a compromise, but I don't have on-board weather station, YET ). This helps me to compare MPG runs better.

CarloSW2
__________________

What's your EPA MPG? Go Here and find out!
American Solar Energy Society
  Reply With Quote
Old 06-22-2008, 01:47 PM   #9 (permalink)
Master EcoModder
 
wagonman76's Avatar
 
Join Date: Jun 2008
Location: Northwest Lower Michigan
Posts: 1,006

Red Car - '89 Chevrolet Celebrity CL 4 door
Team Chevy
90 day: 36.47 mpg (US)

Winter Wagon - '89 Pontiac 6000 LE Wagon
90 day: 28.26 mpg (US)
Thanks: 8
Thanked 17 Times in 16 Posts
Ive wondered about that sometimes. Im sure mine has more mpg available. Reason is I get 32 mpg highway no matter if Ive got the AC on or not, windows down or not, day or night. I just joined up here recently but Ive been driving this same trip for nearly 5 years. I also took a trip to Washington DC a couple years ago and with no stops between tanks I still got 32. I dont exceed the 70 mph freeway speed limit, thats plenty fast enough, I usually go 65-70. The other 70 miles at 55 does not improve mpg. On top of that, my car is not exactly the most aerodynamic thing. Im thinking Ive got enough torque where these things dont make much of a difference and therefore I would benefit from a final drive change.
__________________

Winter daily driver, parked most days right now


Summer daily driver
  Reply With Quote
Old 06-22-2008, 03:06 PM   #10 (permalink)
EcoModding Lurker
 
Join Date: Jun 2008
Location: Central California
Posts: 13

Ratattoui - '96 Geo Metro
90 day: 49.46 mpg (US)
Thanks: 0
Thanked 1 Time in 1 Post
Regor,
I noticed something similar to you this tank as well. Maybe the air temp.
I had "gratuitous" use of the AC on my return trips on my commute this tank because of the heat here in central california. I was able to break the 50MPG ceiling, I believe, because I was stuck behind a big rig for 30+ miles and was able to get a crazy increase in mpg on my ScanGauge2- somewhere in the mid 80's mpg range! I shot up my overall economy without even trying. Maybe you had a similar situation (of drafting).
The experience really does illustrate how much air resistance robs us of MPG. I never would've believed drafting would yield such an increase in mpg, if I hadn't seen it myself. It's almost like driving downhill! All the while the AC was on- so you can bet I'll be looking for more trucks on my commute.
I have also noticed a bit better MPG driving home in the hotter afternoon, than in the mornings, which lends to the warm air increase hypothesis.

__________________
  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com