Drunken Bungle Whore

I know that having the aircon switched on in my car increases the fuel usage. But if I open my windows instead that would increase the drag and would therefore also increase fuel usage.

So which is the most fuel efficient.....?

Dave1980

well i think from memory somewhere that having a window down increased drag by 5%. not sure how that compares but i would say air con is better. dont really notice much of a difference if its on or off really.

Bodgit

I would guess at Aircon/climate on long motorway journeys if you are going below 80mph as anything above this you are not worried about economy. If you are around town etc I would have said window open.

On particualrly hot days when the car has been parked a while I normally open the windows for the first part of the journey to let out the overly hot air and then close them and go to air con. The amount of efficiency waste from not doing this must be huge.

Markus

Beth,
Have a read of this. Look for the aircon bit on there. It's a writeup from the mythbusters episode where they examined this issue.

richs2891

Noticed on mine id have the AC on need a few more revs than normally to get it away from the lights. But cant say noticed much differance with the mpg - probably about 1 mpg worse with it on !

Richard

stilover

If it's very hot put the Air con on. Why drive around hot and bothered with a gale force wind blasting through the windows.

Unless every journey is with Air con on, you'll see little effect in the wallet.

PPPRob

It will depend where you drive (towns or motorways) and what mileage you do ultimately.

I was doing loads of miles and I found the simplest way of saving fuel was to buy another car and keep the scoob in the garage. If you're doing plenty of miles you'll be surprised how relatively cheap it can be.

dpb

Windows down around town ,no aircon .

windows up out of town ,no aircon .

Matteeboy

I lose about 4mpg with aircon on.

MattN

why would you ever switch it off? My climate control is always on ...

The Trooper 1815

iTrader: (31)

10% is about the mark.

Sonic'

If you boot it in the scoob (not sure about other cars) the air con switches off to give you back the power, on cruise it comes back on

My next door neighbour told me a friend of his drove everywhere with the window fully down motorways the lot, he died due to problems with his right ear

TBH I use the Aircon most of the time, even though on my laguna the road speed sensor doesnt work with the air con switched on, so it doesnt always blow cold air, but it is colder than without it

WRX_Dazza

i've always got the window down for the "noise" lol

put AC on when getting in a hot car, and i switch it off once cooled down.

works for me

Abdabz

If I left my climate control on I would get 10% per tank less (so about 27miles a tank less than if I had it off so to speak)...

Billgtt

Air con in a car, I wish

MJW

When I set off on a hot day, I wind the window down a bit and stick the A/C on : that way the hot air in the car can escape and the A/C doesn't have to strain as much. Then once the A/C has been going for 10 mins or so, I wind the window back up

HankScorpio

Yep, me too.

If I was worried about mpg, I'd buy a diesel yaris or something.

There's another stupid eco debate going on about Scandinavian cars where they have the sidelights on all the time.
The addition of two 5w sidelights to the load of an engine driving two tons of Volvo around must me minuscule.

The Snug Rhino

anyone that ever turns off aircon to save a few pence should have bought a bike so they neednt wory about such things.

Leslie

Modern aircons dont use as much fuel as they used to. If you have you windows open DBW it must use more anyway since it is trying to cool down the British Isles as well as your car.

Les

fast bloke

If everyone opened the windows and turned on their aircon, wouldn't it help combat global warming by cooling the atmosphere minutely

SirFozzalot

Stuff the economy, if it's hot, the aircon goes on to keep me cool, that's what it's for!

mart360

I run a diesel, and dont see any increase or decrease with aircon on or off

still get 500 miles to a tank either way

mart