More On Driving And Saving Fuel

So I was driving along the US Interstate over the weekend, and stopped at a rest area on an Illinois interstate (we call them Oasis over here) highway. In the washroom, they have these posters placed in several places, and one of the posters has these things that tells you some "green" driving tips. One of the tips given was something that I had brought up quite a while back. It is on driving with your windows down.

The poster here said this:

Try using vents and opening windows to cool off before you turn on the air conditioner. Air conditioning increases fuel consumption.

Now, if you've read my earlier post when I asked about this, you will also have read the two comments left behind, including one on an investigation done by the Mythbusters folks. Here, it turns out that if one is driving faster than 50 mph, then rolling up the windows and turning on the air-conditioning uses LESS fuel than driving with the windows down and no air-conditioning. The drag forces above that speed causes more use of energy than the air-conditioning unit.

So this poster is not quite up-to-date on "green driving".

Zz.