I am driving every morning to work about 7am and at this time here in Phuket it's not hot out side.

So I just open my window and not using aircondition. My car has 3000cc/V6 engine with 200HP.

I guess it needs 20% less gasoline by doing this?

What's your experience?

Gerd

Noisy

Many years ago I was involved in a survey carried out by the HKAA. We found that in City conditions such as HK, the fuel saving difference for a car running an AC on full cold and switching off was approximately 30% in savings.

But must say, in those days it was thought impractical for a car with an engine size of less than 1200CC to be fitted with AC. Times have changed

" It is estimated that the air conditioning running at maximum setting can lower fuel efficiency by 5-25%.

However, during travelling at high speeds, if the the windows are open, this creates a lot of aerodynamic drag. Thus this may consume more fuel than operating the air conditioner sensibly."

Source: http://www.answers.com/topic/fuel-efficiency

You can't drive without AC in central BKK...it's not so much the heat but the air pollution that makes it impossible. I drove without AC for years in southeast Florida and had no problems. The point made about aerodynamic drag with the windows is a valid one; the car in this case acts like a parachute.

They had this to solve on 'Mythbusters' on the Discovery channel a few nights ago.

If I remember correctly, they found that it was more efficient to open your windows(not using AC) for speeds under 45-50 MPH (or KM?). But over that, to use AC.

They had this to solve on 'Mythbusters' on the Discovery channel a few nights ago.

If I remember correctly, they found that it was more efficient to open your windows(not using AC) for speeds under 45-50 MPH (or KM?). But over that, to use AC.

Mythbusters just re-visited this one. The new conclusion, below 50 mph it's better to have the windows open, above 50 the aircon is the best option.