Tuesday, June 21, 2011

Fuel Efficiency Can be Maximized with Air Conditioning and Windows


A hot car can be remedied quickly by using the modern marvel of air conditioning, but is it more fuel efficient to roll the windows down instead? The answer to this question depends on the speed of your car. We have collected the following advice for drivers who want to cool down their car and save on gas.

When the car is already cool, the air conditioner doesn’t have to work as hard. Car temperatures can quickly rise to over 140 degrees on a hot day. Parking in the shade or in a garage can help reduce the workload placed on the air conditioner. Window shades placed on the inside of the windshield can also help to deflect the sun’s rays. If a car is hot before it is time to go, drivers should open their doors to let the hot air out before cranking up the air conditioning.

When considering whether to ride with the windows down or the air conditioning on, the speed of the car will determine the savings on fuel. A car traveling as speeds over 40 miles-per-hour meets a fair amount of resistance, or drag, from the air moving around it. Like a parachute opening, the drag is increased when the windows of the car are rolled down. More resistance means the car has to work harder to get down the road. In these instances, it is better to ride with the windows up and the air conditioning on.