Windows Down or Windows Up?

Now that spring and summer are approaching, temperatures are increasing and gas prices are rising. This brings up a question, is it more fuel efficient to drive with your windows down with no air conditioning? Or is it more fuel efficient to have the windows up, eliminating drag with the A/C on? I have some information for you to consider.

            Studies conducted at a GM wind tunnel show that driving with the windows down consumes more fuel than does the air conditioning at speeds above 50 miles per hour. According to sources, with the windows down in a car, efficiency drops by 20%; it drops 8% with a large SUV. At these driving speeds, it is definitely more fuel efficient to drive with the windows up and A/C on.

            Now how about when you are just driving around down at speeds under 50? Driving at the lower speeds reduces drag so it is actually more efficient to drive with the windows down. However, be wary of acceleration, drag increases exponentially, so by going from 35 to 70, drag does not double, it quadruples.

            A good rule of thumb, experts say, is 40 miles per hour. So at 40, switch over to you’re A/C. There are also other studies and tests that argue windows down all the time is better. In my opinion, driving with the windows down and sunroof open are worth losing the gas efficiency.

Happy Motoring