HOW MUCH MORE PETROL DOES A CAR USE WHEN THE AIR CON IS ON

Question

Does the other option of opening a window also invrease the petrol uesd?

Answer 1

It depends on the make and model.

I just (last month) did a test, with the top down on my Miata, I got 33 miles per gallon. Then I made the same  run with the top up and the AC on and got 30 mpg.

Answer 2

Loads about 20 percent more, everything u use in your car uses petrol like when u have the windows open and even uses a tiny bit when u have the cd player on.

Answer 3

The air con should be electric and use no petrol.

Answer 4

Some air con is electric and some is a belt driven compressor.

The latter uses some fuel. The manufacturers haven't yet seen fit to tell us how much. If you have a display which reads out mpg constantly (as I have) you should be able to see an effect when you switch it on or off providing you are travelling at a constant speed on level ground.

I have tried this with my diesel Picasso and cannot produce any change. So I can only assume that the extra fuel used is so small as to be negligible. I had a hire car, small petrol, which actually lost power when you turned on the air con. So I suppose there is a greater effect with some vehicles than others. The air con design must feature as well.

Answer 5

Agree with Portside, knocks about 2 mpg off. Running with windows wide open will drop about 5 mpg at motorway speeds. Best economy/comfort is a/c off, one window one inch open and air vents on cold

Answer 6

That depends on the car but as a whole they do use more petrol because of the power consumtion on the battery,All aircon motors are run by belt but need power to run properly..Switch on the aircon and you will most defo here the engine note drop then rev a tiny bit more than if it was turned off..Best Regards Steve  

Answer 7

Same  engines it hurts some larger engine little to none> HWY none> Ask your wife or GF if she wants it on that will tell you how much does it cost>