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Automotive Fuel Efficient

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hitechaes

Automotive
Jan 29, 2014
1
Fuel Efficient and Economical: Windows Down or A/C On?

Hi-Tech AES (Automotive Engineering Services)
 
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Windows Up - A/C Off --> Most fuel efficient and economical
 
from ten years ago

TTFN
faq731-376
7ofakss

Need help writing a question or understanding a reply? forum1529
 
mythbusters did this IIRC. dont remember the outcome
 
They said a/c on, in their particular test, in their particular vehicle, on one particular day, was better. I somehow doubt that one test covers all vehicles and all duty cycles

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Best economy is to have windows up and air-con off, if you're girlfriend complains about the excessively hot cabin try wetting her T-shirt with water. (be careful with this method, as often the following activities can result in an unwanted pregnancy which totally kills economy).
 
Of course mythbusters is about as scientific as trying to measure the mass of dog farts with a tape measure.
 
given that the power to overcome drag is a function on velocity cubed defining the speed is a slightly important. it would be hard to imagine that opening the windows on a modern German car travelling on the autobahn at 120mph+ would use less fuel than a modern efficient A/C system. it is also hard to imagine that in bumper to bumper traffic of a few MPH that opening the windows would have any meaningful effect on fuel efficiency but the parasitic loss would be measurebable
 
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