I will use my A/C in hot weather when needed (heat too) - period. However, in mild weather I do have the option of running windows up with the fan on or running windows down with the fan off. My change-over point is about 35 MPH. I don't find the smart particularly comfortable at 55-plus with the windows open (noise, mostly).
Anyway, those owners with ScanGauges installed should be able note the differences in very short order. Even if the MPH readout isn't spot on accurate, the relative differences ought to be recordable.
I've always found that AC consumption runs from 10% to 20% for most cars. From the few times I've used it (about 4 tanks out of 60ish) I've seen about a 12% hit. I'm sure folks in the mid-states could tell you better though.
Reality is, if you're driving a car and using AC, the smart is probably your best option. AC use in almost all cars just clutches in a drive wheel for the compressor, so the more efficient your engine, the less gas you use for AC. Plus in the smart you're conditioning less air (though there is a larger light permeable surface area). I'd bet the same amount of AC usage in a smart vs any other car will result in more fuel usage in the other car than in the smart.
Personally, I like having the top down, so the few times I've used the AC have been on hot days where it was rainy, or where even the wind blowing was hot.
Air conditioning takes a huge hit on my smart. I live in Florida and it's hot this time of year! When I drive without AC, I can easily exceed 40 mpg on my scanguage's trip total. When I turn the AC on, I don't get much over 34 or 35 mpg.
I can believe the 30% figure mentioned above, that's been my experience driving the smart in city traffic.
I've found that I do a lot better if I turn off the AC when accelerating and turning it on again when reaching cruising speed. I leave the AC on through cruise, deceleration and sitting at the light. When the light goes green I cycle it off again and accelerate. I press the "A/C" button to cycle the AC compressor, the red LED indicates the AC is on. Using this technique, I'm averaging 38-39 instead of 34-35 with the AC on in city traffic.
Try cycling the "A/C" switch under acceleration, you can easily feel the difference.
Air conditioning takes a huge hit on my smart. I live in Florida and it's hot this time of year! When I drive without AC, I can easily exceed 40 mpg on my scanguage's trip total. When I turn the AC on, I don't get much over 34 or 35 mpg.
I can believe the 30% figure mentioned above, that's been my experience driving the smart in city traffic.
I've found that I do a lot better if I turn off the AC when accelerating and turning it on again when reaching cruising speed. I leave the AC on through cruise, deceleration and sitting at the light. When the light goes green I cycle it off again and accelerate. I press the "A/C" button to cycle the AC compressor, the red LED indicates the AC is on. Using this technique, I'm averaging 38-39 instead of 34-35 with the AC on in city traffic.
Try cycling the "A/C" switch under acceleration, you can easily feel the difference.
Let me know if this works for you.
Bob
Using your own figures; even your worst case (6 mpg hit) that's only 15% ! I can live with that to be comfortable
Granted, 15% isn't a big hit, but I like to see how high I can get the mileage. It's a game I enjoy playing in the smart.
I used to have a car which automatically turned off the AC compressor when you were accelerating hard. The AC would blow warm after a hard charge up an interstate on-ramp. The manufacturer figured that if you floored it you wanted full power.
Maybe someone could work out a mod for the smart to let this happen at a lower level of acceleration?
I've already experienced the AC compressor not working at high speeds because in all probably the vacuum dropped too much and the sensor decided to deny it to work. As I coincidentally traveled towards the dealer on a regular road and slower speed it all worked well again. As for consumption with AC... it's enough. I believe it's about 4-5 mpg less. Idling must cause this and I get into traffic frequently.
A new problem has cropped up however now, ever since I had the transmission updated, the little car stumbles at first from stand still to moving when the AC is on. Not good.
Your vent dial has 12 settings with three points of 100% of the air one direction: at 4 o'clock the air is 100% out of the console vents, at 8 o'clock the air is 100% out of the floor vents, at 12 o'clock the air is 100% out of the windshield vents. It's the 12 o'clock position I call "full up" venting because SO many people talk about the 12 o'clock position being the "defrost" setting which doesn't describe the reason I want to blow air there.
When the vent is turned to all-windshield at the 12 o'clock position, the A/C is automatically engaged even though the A/C button has not been pressed nor is there indication the A/C is on from the LED on the button.
So. If your vent dial is set to 12 o'clock or "full up" your A/C is on unless the outside temperature is approaching freezing.
as long as we agree the 12:00 position is for defrost, which it indicates. and you get 100% more efficency when the compressor does run because its now blowing drier air to defrost with, max efficency would be to raise the heat to max also.
but it really doesnt matter how you use it, as long as your happy.
It is NOT DEFROST when I turn the vents up to the windshield. It's windshield airflow!!!!
I need actual defrost for 15 minutes a year. I want window airflow for the rest of the time. I sit with the dial at 11 o'clock to accomplish that but I shouldn't have to. It's BOGUS.
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