Increase Your MPG and Reduce Emissions by Driving Efficiently

With summer travel plans and rising fuel costs, it seems like everyone is looking for ways to improve their gas mileage. New cars are becoming more and more fuel efficient and the popularity of hybrids, EVs, and alternative fuel vehicles are increasing. But what if you aren’t looking to buy a new car? The good news is you can increase your fuel mileage and reduce emissions just by making a few small changes to the way you drive.

First, as tempting as it may be to run the A/C for a few minutes before getting into a hot car, unnecessary idling both wastes fuel and puts unnecessary wear on your engine. Instead, consider parking in the shade where possible or cracking your windows. When you must park in direct sunlight, the use of a sun shade can reduce the ambient temperature inside your car by more than 40 degrees F, and thus greatly reduce the need to blast the A/C on startup.

Second, the classic air conditioning vs. windows down debate. The A/C unit draws power from your car’s engine, so running your car’s A/C will both decrease fuel mileage and blunt your car’s performance. But rolling down your windows also increases aerodynamic drag. So which is best? The answer is that at city speeds (less than 45 mph), the increase in aerodynamic drag caused by the open windows is negligible. So at slower speeds, it is (on average) more efficient to turn your A/C off and open your windows. But, at highway speeds, driving with open windows can increase drag by as much as 20%. So generally speaking, above 55mph, it’s actually more efficient to drive with the windows closed and your A/C on.

Third, and perhaps most importantly, smooth driving makes a huge difference on fuel economy. Hard acceleration requires a lot of fuel, so smooth acceleration and early shifting can will improve fuel mileage and reduce emissions. Similarly, using the brakes simply turns your car’s kinetic energy into heat. So planning ahead and coasting to a stop, rather than braking hard, will also save fuel (and in a modern manual transmission car, coasting in gear actually consumes no fuel at all).

To illustrate the point about driving style, consider this: the Toyota Prius has an EPA combined rating of 50 mpg. But…drive the same Prius at maximum attack (for example, around a race track), and you’ll be lucky to break 20 mpg!

In short, regardless of what vehicle you drive, small changes in driving habits can make a big difference on fuel economy. So help protect the environment (and save at the pump)… avoid unnecessary idling, know how to efficiently cool your car, and—most importantly—drive smoothly.