Author Topic: How much does A/C "cost"?  (Read 5476 times)

Offline branchespark

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How much does A/C "cost"?
« on: 22 February 2011, 08:24 »
My journey in to work today was slow. Super slow. So, while dawdling along the A14, I decided to reset the consumption and see what MPG I get in my GTD with and then without the A/C on.

Without the A/C, I managed to get over 71 mpg over 15 miles. OK, this was at about 55 mph, but still a good number.

With the A/C on, it dropped to about 69 mpg. So, does A/C only cost about 2 mpg in winter (probably more in summer) or should I have seen it "cost" me more?

For the record, I had the temp on 19 deg, low auto.


Mk6 GTD 5dr | Manual | Deep Pearl Black | 18" Vancouvers | Leather | Xenons | RNS510* + VW Premium Bluetooth (iPhone4) + Dynaudio | Smoked LED tails | Cruise

Offline R32UK

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Re: How much does A/C "cost"?
« Reply #1 on: 22 February 2011, 08:37 »
i never use mine so wouldnt know... have done previously and it was roughly 2mpg

Offline Rhyso

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Re: How much does A/C "cost"?
« Reply #2 on: 22 February 2011, 09:00 »
At 4 degrees I'm fairly sure you AC isn't even on.....

Under 5 degrees it doesn't come on, only the normal fans  :undecided:

Offline Wayne

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Re: How much does A/C "cost"?
« Reply #3 on: 22 February 2011, 09:33 »
At 4 degrees I'm fairly sure you AC isn't even on.....

Under 5 degrees it doesn't come on, only the normal fans  :undecided:

I think your correct it only works 5 degress and above  :smiley:

Offline branchespark

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Re: How much does A/C "cost"?
« Reply #4 on: 22 February 2011, 09:34 »
OK - sounds sensible!

What should I expect the cost of the A/C to be then? 3 mpg? more?
Mk6 GTD 5dr | Manual | Deep Pearl Black | 18" Vancouvers | Leather | Xenons | RNS510* + VW Premium Bluetooth (iPhone4) + Dynaudio | Smoked LED tails | Cruise

Offline The Doc

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Re: How much does A/C "cost"?
« Reply #5 on: 22 February 2011, 09:37 »
At 4 degrees I'm fairly sure you AC isn't even on.....

Under 5 degrees it doesn't come on, only the normal fans  :undecided:

I think your correct it only works 5 degress and above  :smiley:

I'm sure that your both correct, it only works at 5 oC and above  :rolleyes:

Offline Rhyso

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Re: How much does A/C "cost"?
« Reply #6 on: 22 February 2011, 09:41 »
OK - sounds sensible!

What should I expect the cost of the A/C to be then? 3 mpg? more?

I've always found that it has a negligible effect on the car's MPG  :undecided:  I find that the car is much more sensitive to temperature than if the AC is working or not

I guess a lot varies on the conditions i.e hills, traffic and how you drive

Offline The Doc

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Re: How much does A/C "cost"?
« Reply #7 on: 22 February 2011, 09:43 »
What car says "5-10%"

Anthony Sale, senior powertrain engineer at Millbrook  "the difference in fuel use between the baseline run and with air-con on is virtually nothing"

US government "Operating the air conditioner on "Max" can reduce MPG by roughly 5-25% compared to not using it."

I say around 2 MPG if it's hot  :wink:

Offline Wayne

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Re: How much does A/C "cost"?
« Reply #8 on: 22 February 2011, 09:44 »
Still got to be cheaper to run the air con than to open a window at say 30 / 40 mph

Offline The Doc

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Re: How much does A/C "cost"?
« Reply #9 on: 22 February 2011, 09:50 »
You have windows on your bike? you posh git  :grin:

I agree, I never turn it off anyway  :wink: