As gas prices across the country go through the roof, people are becoming more innovative in ways to conserve their car’s fuel consumption. Some people think that by turning off a car’s air conditioner and letting Mother Nature cool the air, the car will burn less fuel. Others vehemently disagree.
A couple of weeks ago, we published a story on this debate: ”
Will rolling down windows save fuel or not?” The experts say when driving around town, turn off the AC and roll down your windows. However, keep the AC on and windows up when traveling on the highways.
That’s what the experts said, but we wanted to know what real people, driving cars back and forth to work or taking the children to school and soccer practice, are experiencing. So, we asked: What gets the best mileage on your car — windows down and the air conditioner off, or windows up and AC on?
Here’s what you had to say.
For some readers, speed is the issue:
My car is a 1999 Ford Taurus with a V6, 3.0L engine. When it’s super hot, I cool down my car by opening the windows to get out the big heat. Then, I crack open the passenger’s window a bit and the driver side window behind me to get a cross draft going on. This draws the heat out when it gets too hot. After doing that, I turn on the AC until it cools down, then turn the AC off and the fan on to mid-point.
I drove this way from Long Beach, Calif., to Florida and back and consumed about 28 miles per gallon the whole route, including mountains. I didn’t need to go over 65 mph. And when my car is not loaded, I get about 33 to 35 mpg.
Slow-it-down Vince says:
I get the best gas mileage driving with the windows down, AC off and observing the 65 mph speed limit. I drive a Hyundai Santa Fe, which is rated at between 22 and 26 miles per gallon on the highway. By driving without air, at 65 mph, I get 27+ mpg. I used to drive 72 mph, but now I save almost 5 mpg with the drop to 65 mph. Also, I try not to go over 3000 rpm on acceleration. In other words, I drive like I have an egg under my foot.
Windows down, AC off
Paul times it right:
I have a Civic Hybrid. I am averaging 45 mpg over 18 months of ownership. My air conditioning decreases my mileage by 10 percent, but here’s what I do: I schedule my trips either very early in the morning or after 6 p.m. I drive at night when I’m going for a long trip. When I’m in town, my windows are down. On highway trips, I keep the windows up and ventilation fan on high. Morning air and evening air are comfy.
Because of my age and health problems, it is imperative that the air conditioning is on. But, if I was, say, 18 years old again (I’m 72), I would keep the windows down at slower speeds and save gas. In the old days we loved to ride with the windows down. The smell of fresh air and wind going through my hair (don’t have hair now) was delightful.
I use the AC as little as possible. But my wife uses it all the time, even on days when it’s not very hot. As a consequence, we’ve had to replace cars, more often because the AC failed and couldn’t be fixed; or would be extremely expensive to fix, than any other reason. To me, that’s an important reason for not using the AC (unless it’s really hot) than getting better gas mileage. For highway travel I roll the windows down just a little. At the higher speeds, that gives good air circulation with less drag. I’d rather do that than have to get a new car after three years just because the AC failed.
Windows up, AC on
Jeannie scores a point:
The air is re-circulated so that it does not have to work so hard cooling the hot air. Also, you don’t save any money if you get sick from carbon monoxide fumes in traffic.
. Brubaker fumes:
Obviously the people conducting this study do not live in Phoenix. The hotter it is the more driving rage we experience here. The subsequent accidents slow down traffic and are then much less efficient.
Windows up and air on. You talk about road rage — just live in the South where you live and work in air conditioning all day, then tell me to drive in heat and humidity?! Road rage is just a turn of the ignition key away.
Helen is NOT interested in reminiscing:
You didn’t address the people who live in the tropics, like Florida. From the central part of the state to the bottom, it’s hotter than- -, even with the air conditioning on. We just have too much sun. We can’t function (i.e., breathe) for about eight months out of the year without air conditioning everywhere, including cars!!
You might want to contact Toyota, who states clearly in their manual for the 2004-2005 Prius Hybrid that driving with the windows down increased drag and reduced gas efficiency over using the air conditioning. But then, their air conditioner works from an electric compressor, allowing engine off while still cooling.
Perhaps, if you really want to impress gas savings on your readers, you’ll look inside the bigger box: Owner of three hybrids, solar-electric panels on my house, and loving them all. Get on board, do your part, too!
Gordon, a physics teacher weighs in:
Just as around the house, dry air, with fans moving the air, is the key to the cheapest comfort. Placing the temperature control at a higher setting controls how often the AC compressor is on and minimizes how much the AC is actually in the cooling cycle. Only when the compressor is on is it putting a load on the engine and using more fuel. Just an occasional operation of the AC’s compressor dries the air and the fan, along with the re-circulation switch keeping out moist air from outside, maximizes comfort. It’s the same around the house. Higher temp settings and ceiling fans is by far the best way to economical comfort. Ask your home air-conditioning service man.
WHA stands firm:
If you’re concerned about fuel economy, then ride a bike. As for me, it’s full speed ahead with the air conditioning on. You could pull the seats out and remove anything you’re not using, like the spare. All these things will reduce fuel economy — but at what cost? I like my comfort.
I don’t really care about this debate. It’s a question of being comfortable in 90-plus degree heat. Use the air and be comfortable. You only live once.
B D controls his comfort zone:
Roll down the windows with the AC off when driving under 40-50 mph as long as it is bearable.
Roll up the windows, set the air to recycle, and manually cycle the AC on and off to maintain a bearable environment. It appears that most cars’ air conditioners, with temperature control, operate with the AC on at all times and maintain the set temperature by cycling the heater. This, of course, results in wasting energy to keep running the air conditioner when it is not required.
Or, you could follow this hardy reader’s advice: Move to Alaska and you’ll not have to worry about this!
Do you have any tricks? Bankrate would like to hear
what gets the best mileage on your car.