Recently I was asked after that single hot summer day we had which is more fuel efficient, to drive with your windows down or to use the air conditioner? The answer is surprisingly loaded with a lot of variables.
Every vehicle typically spends 7-15% of the fuel in its tank fighting wind resistance, the actual number depending on the particular model and how fast it's traveling; higher speeds mean more wind resistance. However, this number is increased when there are additional factors to cause wind resistance, such as a window flag, a rooftop storage pod, or the windows are down. The faster you go, the more fuel you burn due to the increased air resistance created by having the windows down.
While air conditioning keeps you cool and aerodynamic, it also comes with a price, generally a 10-25% decrease in fuel economy. The wide variance here is once again, a factor of speed; stop and go traffic means burning the fuel to go nowhere at a stop and burns extra fuel to power the air conditioner, while traveling at highway speeds the penalty is much lower as it just uses a fraction of the power being generated by the engine.
The best solution isn't to use one or the other but both. Turn off the AC and wind down those windows. Enjoy the summer breeze when traveling below 50 MPH, especially if you're in stop and go traffic. Out on the interstate, the autobahn of I-696, wind those windows up and turn on the cool AC. If you're not used to it, it may be a chore to remember to switch back and forth, but believe me, it'll become second nature in no time and the fuel savings can be worth it.
Comments
I drive with the windows open in the summer and closed during the winter. My summer MPG is greater than my winter MPG due to gasoline formulation. Open the windows and enjoy the fresh air when you can. This is a myth that you get better mileage with the windows closed and A/C running at any speed. When ever I use the A/C In the summer I notice a 20% reduction in mileage compared to the days I leave the windows open.
Got something to say?
Examiner.com is looking for writers, photographers, and videographers to join the fastest growing group of local insiders. If you are interested in growing your online rep apply to be an Examiner today!