Do you really save on gas by turning off the AC and rolling down the windows?

Question

This is a debate between my husband and myself. He says that you save on gas if you roll the windows down and I've heard different! Please help...we're making a bet on this!Thanks a bunch ; )

Answer 1

depends on how fast the car is going and the aerodynamics of the car.  As a car goes faster, the wind resistance pushes in the open windows and gets bogged down, causing wind resistance and less mpg.  There is an individual speed for each car that determines when it is better to have the AC on or the windows open.

Answer 2

These techniques can save on fuel but if you are familiar with hypermiling, this technique basically says for example that the windows should be rolled up. Why, because it will cut down on the drag on your car which will consume less gas.

Answer 3

yeah using the ac wastes a lot of gas.

you can also save gas by changing the gear to neutral whenever you're slowing down for a red light or something like that.. idk my dad does it all the time

Answer 4

If its a comfy day and your driving highway speeds, roll up the window and use the FAN option only, no AC so it brings in the cool air from outside inside and thus not using much fuel as your engine is not working hard to cool down inside as the cool air is coming from the outside. Use AC for only days that is super hot, in the city use the windows, for highways that are not sticky or HOT days, use the FAN, not AC. Good Luck! Thats what I do in my SUV and it helps save fuel and less CFC in the atmosphere.

Answer 5

If you're in a normal car at suburban speeds, windows down AC off.

Ignore what everybody says about Mythbusters. They used an SUV that was so big that the AC didn't make much of a difference because the amount of gas needed simply to shift the bulk of the vehicle masked the data.

Answer 6

If you are driving at highway speed, the disrupted aerodynamics from the windows being open (and the resulting additional drag) will consume more horsepower than running the A/C.  

Tell your husband to roll up the windows and keep his wife comfy.

Answer 7

If your traveling high speeds and have the windows rolled down it will make your car work harder cause there is less aerodynamics.   Also you can use more gas while running your A/C so honestly its a no win situation.  I would roll windows up when traveling on the highway and use the A/C sparringly.

You can read a bunch of gas saving tips in this article I found below in my resource.

Answer 8

For best MPG:

HWY speed - AC on and window up.

STREET speed - AC off and window down.

The BEST - AC OFF and window UP.

I was out today and was just going for a short drive. The above was kind of moot because it was so hot I could not drive with the AC off (which I normally prefer - regardless of cost).

Good Luck...

Answer 9

no you don't myth busters did a test on this and found that you don't save enough to even notice it,yet people still do it,but on most cars built with in the past ten years its just as cheap if not cheaper to run the air conditioner as to roll down a window,good luck.

Answer 10

it depoends on the vehicle your driving, type/size of engine, how much the compressor boggs the engine down, the type of driving your doing(city or highway).   there are many variables to this question, too many to answer.