What wastes more gas: Having the windows rolled down or air conditioning?

Answer 1

Even though the auto industry insists that the ac does not use fuel to run it does cause worse gas mileage than having the windows down or the top down on convertibles or t top vehicles. the reason the ac puts a strain on the engine and to compensate for this the engine takes in more fuel to keep running at optimum performance. if you want to see a demonstration of this activity done in real life check out discovery.com and go to mythbusters they did a segment on this and showed how the ac reduces your gas mileage.

Answer 2

Technically, air conditioning uses slightly more gas, but the difference is so negligible in most cases that unless you own an SUV, you shouldn't worry about it. The question is so hard to pin down that entire studies have been done (see link below), but conventional wisdom is that if you're really trying to save every last drop of gas, leave the windows down in city driving and use the AC at highway speeds. But getting a more fuel-efficient car in the first place will let you use the AC guilt-free so you won't have to sweat it.

Answer 3

I think that the Mythbusters episode on the Discovery Channel used a flawed experiment. They used two big SUVs traveling at 45 mph. They found that the economy was better with the windows down and the AC off. But if they used a small car with less drag going 70 mph, they might have found that the economy would have been better with the AC on and the windows rolled up.

Answer 4

Having your A/C on wastes more gas for Certain.

Initially you might think that having your windows rolled down would create more drag, and resistance holding your car back. However, running your A/C forces the car to work harder while running, which in effect uses more gas.

Answer 5

Depends on the speed you are travelling. At low speeds air conditioner wastes more gas. At high speeds the wind resistance you face from having your windows rolled down will cause you to waste more gas than having the air conditioner on.

Answer 6

A/C on does not waste gas. That is a myth. Windows rolled down is also a myth because the drag created is too insignificant to waste gas.

Answer 7

OPEN WINDOWS ARE MORE FUEL EFFICIENT!


Myth statement:

Running a car with air conditioning on is more fuel efficient than running with the windows down.

Status
Busted

Notes
Tests were performed under varying conditions (55 mph versus 45 mph). Also, the 55 mph test was using a computer to estimate fuel efficiency based on air intake, not actual fuel consumption, and showed A/C was more efficient. The 45 mph test consisted of running the tank until it was empty, and showed open windows were more efficient.

Answer 8

it depends. below 40 - 45 mph air conditioning waste more gas, above 45 mph the wind coming into the car hits the back window and wastes more gas. so at slow speeds windows are more economical and at highway speeds air conditioners are more economical.

Answer 9

If your on the highway, rolling down the windows wastes more gas (it creates more wind resistance and makes the engine work harder to maintain speed). City driving, A/C wastes more.

Answer 10

Having the windows rolled down while running the air conditioner!