How much does your petrol consumption increase when using aircon?

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shadow_man

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How much does your petrol consumption increase when using aircon?

I recently bought a Opel Corsa Classic 1.6i Sedan and have noticed that my petrol consumption per km seems to be a lot worse than my Honda Ballade 1.6i.

On the Corsa I'm getting like 80km per R100 of Petrol.

On the Honda I was getting like 100km.

The only difference in my driving habit with these cars is the aircon use.

Everyone said the Corsa would be lighter on petrol. So far I can't see how.

I have yet to take the Corsa on the open road so I can't really say for sure what the consumption is like on the open road.

I am going to take it out to the coast this weekend for a nice long drive and see.

J
 
Depending on the car, my Polo goes from 0.7 to 1.2 l/100km when turning on the aircon so it is just short of double. Though on the open road going faster then 80 it seems to then go to about 1 l/ 100km less then with it off and a window open.
 
It will vary from car to car but I hear it's generally more fuel efficient to use an air con than open the window when traveling over 80km/h because of airodynamics.
 
in the fiancee's car (sirion) turning off the aircon is like a 10kw boost in power :D
 
It depends on how big a % of the engine power is driving the aircon i.e. smaller engines you save more than on bigger engines
 
Also depends on the aircon unit. The little electric ones designed for small cars hardly make any difference. Just done 1200 km in the Polo with aircon on all the time and got 6.2 l/100, so I really think it's academic, as I was up in northern Zululand where the outside temp according to the car was 41C...no aircon would have been suicide...if I lost a couple of litres, I really couldn't give a damn! :D
 
Funny, with my Corolla I don't notice any difference in fuel consumption whether I drive with the aircon on or not...
 
Ry4n said:
It will vary from car to car but I hear it's generally more fuel efficient to use an air con than open the window when traveling over 80km/h because of airodynamics.
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Mythbusters proofed that statement to be incorrect.
 
TheGuy said:
Mythbusters proofed that statement to be incorrect.
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Incorrect or not, the difference between driving with or without an aircon is negligible, and probably comes down to points of a litre in the end, which the average driver here is likely to screw up whilst dicing away from a robot anyway...switch the bloody thing on and be comfortable!
 
To be honest I haven't noticed it at all, I have my aircon on all the time, but I still get my 2 weeks worth of miles out of the tank, avg 40 miles to and from work.
 
Generally difference is minimal besides u would only switch on air con when u need it...interestingly friend who drives a Proton says you can feel a definite reduction in power when aircon is on
 
marco79 said:
Same here. No difference in my Corolla. I usually get 12.5 to 13 km per litre with or without the aircon on.
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Toyota Corolla 1600 GL FTW!!! :D:D:D:D

Aircon need to be overhauled :cry: It still works, but at 60% capacity :(

Think it's the original unit which came with the car :D
 
Fazda said:
Also depends on the aircon unit. The little electric ones designed for small cars hardly make any difference. Just done 1200 km in the Polo with aircon on all the time and got 6.2 l/100, so I really think it's academic, as I was up in northern Zululand where the outside temp according to the car was 41C...no aircon would have been suicide...if I lost a couple of litres, I really couldn't give a damn! :D
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I have yet to see one of these "little electric" air conditioners I hear so much about, would you mind pointing out which vehicles they are fitted to?

I've said it before but there is no more efficient way to cool down a gas known to man than the Carnot cycle, which comprises of a compressor, evaporator, etc. (IE. the principle used by a normal air conditioner).

The compressor is usually driven by the crank shaft (hence the loss in power when turning on the air conditioner), now I would assume an "electric" one, the compressor would be driven by an electric motor, but that would mean lower efficiency. The alternator has loss and electric motors have loss, so you'd be using more power than driving the compressor directly from the crank shaft. First law of thermodynamics makes it impossible for the electrically driven one to be more efficient (unless you have 100% efficiency for both the alternator and electric motor which is impossible) unless the compressor itself were more efficient. Which also doesn't make sense because why not drive it directly from the crank shaft then?

Sorry for the rant but I'm just curious about these air conditioners because people keep asking about them and I don't believe they exist.

Anyway it depends highly on the vehicle, Opel's seem to be hit hard when it comes to air conditioners, possible because it's not a quality unit. But I have yet to drive a small car that doesn't take a huge hit from turning on the air conditioner. Small being 1400 and less.
 
Gnome, lift the bonnet on a small Jap or Korean car, and you will find one. You can start with a Yaris.
 
Fazda said:
Gnome, lift the bonnet on a small Jap or Korean car, and you will find one. You can start with a Yaris.
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I've checked a Atoss (friends sister had one), Yaris (friends sisters new car after she destroyed the Atoss) and friends Kia Pecanto so far. All had belt driven compressors.

Also all 3 of those cars took huge hits from turning on the aircon, that includes the Yaris, feels like you suddenly picked up an extra ton in the car.
 
Gnome said:
I've checked a Atoss (friends sister had one), Yaris (friends sisters new car after she destroyed the Atoss) and friends Kia Pecanto so far. All had belt driven compressors.

Also all 3 of those cars took huge hits from turning on the aircon, that includes the Yaris, feels like you suddenly picked up an extra ton in the car.
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Strange...my Yaris didn't bat an eyelid when I put on the aircon...maybe because I live at the coast.
 
Fazda said:
Strange...my Yaris didn't bat an eyelid when I put on the aircon...maybe because I live at the coast.
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Must be, which one was it, hers is the 1L Yaris (or something like that), I think there is a 1.4 one also? Anyway she had the smaller one. Damn it was slow with A/C on!
 
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