As some may have noticed: with the AC on down goes the mpg. Why can't someone make an electric AC unit for cars? Then like the power steering pump leaching off hp from the engine the AC wouldn't either! Does this sound like a 'good' idea?
BTW today I was tooling down the highway and barely noticed a 1980 MG one the interstate. Well, when I got off he seemed to be going in the same direction. At a stoplight on the upramp he motioned to me and I put my passenger window down. He told me that my blue FIT was a great looking car and was awsome... hmmm... it seemed that he was watching the car on the road and saw how my Fit had handled pretty well. I don't know about you but, I took it as a compliment!
One thing that makes my Fit stand out now is the Mugen visors! Now all I need is springs (EIBACH), strut bar stiffeners... etc

 

You don't seriously think power (electric) is free?


Sure, an electric AC compressor would probably be less taxing on the engine, but it would require a larger alternator, which would increase drag on the engine.

You don't get something for free. It's the law of conservation of energy.

 

I think it's your head. Mileage should not go down noticeably. Cooling the temperature uses way less energy than pushing a 2400lb piece of metal.

btw i had the same exp of the stoplight, but it was a ford explorer (but it wasn't the driver. it was the passenger wanting to chat about my fit).

 

A car running with its AC on uses 20% more fuel thats a noticeable decrease in mpg.

 

i odnt know about you, but when i blast AC the whole time, i got 1 mpg less than normal...

and that's 70 mph cruise control on the way to LA

 

My home a/c runs on electricity and it sure as hell is not free. A 12-volt electric motor powerful enough to power an a/c compressor would be about the size of a loaf of bread and a alternator the size of a spare tire. I would like to see that packaged under the hood.

 

I get about 38-40mpg on the HWY without, and about 36 or so with AC on.

 

It's a myth that AC uses that much gas. in fact, sometimes, turjning on AC is a better choice than rolling down windows.

In CA a while ago we had a "flex alert" meanign we ran low on power. one of the advice they gave was use the car's AC cuz it does NOT use that much gasoline. if u notice a gas mileage drop, it's trivial or by luck. if you do enough measurements and statistics of mileage vs AC, u'll see it doesn't do anything.

just google. here are links i found
http://www.google.com/search?hl=en&q...=Google+Search
some spread the myth, but most of them denounce it.

 

Yeah I kinda wondered about that. But the alternator would have to be massive to drive the current need of the a/c compressor. Of course when everything's hybrid and the alternator and starter is one unit large unit, I think it's feasible.

Another thing... they should have thermoelectric generators on cars. Current units made for remote applications weights about 128 kg and generates only 100W. It's not much, but if you can reduce the weight it would be nice to capture some of that wasted energy.

BMW is working on a exhaust heat/steam turbine thingy to capture the waste heat and turn it into motion. Pretty cool if they can pull it off.

 

My Mx6 gets WAY better mileage with the AC on. Im doing tests per tank. I did a 50/50 for the first tank. I drove with the AC on to work and the windows down on the way home from work.

I got 218miles. Around 20mpg. Yes, horrible.... thus the reason Im getting the Fit.
Right now Im using AC all the time. BUT, Im using it on the "economy" setting. Basically it uses the compressor less and recycles the cold air. Doesnt blow as cold as it should (noticeable) but it still works. Its definitely saving gas! Im at 110miles and I just past 3/4 tank. Thats pretty damn good. Best MPG Ive ever had with this car.

I have not boosted once on this tank. Its so tempting but Im testing.

Upgraded fuel pump, injectors, and a hacked VAF.

 

I believe the Scions, at least the XB, use an electric driven compressor for AC. I haven't heard of gas mileage problems with them that come close to the issues with the Fit.

Of course it costs to use the AC...as someone mentioned, nothing is for free. It may not be much, but it will still affect gas mileage.

 

Titefit you are right! And don't I know it. My AC unit deareases the milage by a lot! For the past few days I have run it less and the mpg has gone up noticably. Thanks to the Mugen visors.

 

My wife's Prius has an electric AC unit & with or without it she gets 49 mpg all the time.

 

Thanx for your post! That is what I'm talking about. Maybe Honda will catch up with your wife's Prius