
Experts find key to saving fuel: say gallons per mile - czik
http://www.guardian.co.uk/environment/2008/jun/20/travelandtransport.carbonemissions
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frouaix
If you cross the pond often, it's useful to remember the following: x mpg * y
l/100km = 240 (or more exactly 235 and change, but 240 has more divisors and
is easier to manipulate).

Illustrated:

10 mpg = 24 l/100km

20 mpg = 12 l/100km

24 mpg = 10 l/100km

30 mpg = 8 l/100km

40 mpg = 6 l/100km

60 mph = 4 l/100km

Small cars in EU are i the 4-6 l/100km range, or between 40-60 mpg. Sedans are
typically between 8-12 l/100km, or 20-30 mpg.

HTH

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teamonkey
My brain's frazzled. Are you using US gallons or Imperial gallons in those
calculations?

I'd suggest they go a step further though. The first thing I do when looking
for a new car is convert the mpg figures into pence per mile.

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seano
If they did that then the figures would change daily and be different for each
market in which the car were sold.

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michaelneale
if it could be done in a way you could see something updated a week, would be
interesting - maybe would make people think twice before a longer trip (would
work with me).

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ComputerGuru
This is the kind of rephrasing of concepts that's just so ingenious and makes
you wonder why no one thought of it before. Props to the people behind the (so
obvious, so effective) idea!

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ovi256
Uhmm, it's been used in the rest of the world (I can vouch for Europe) since
forever? In the form of liters/100km.

~~~
ComputerGuru
OK, then props to whoever is bringing this idea to the USA :)

That's like pointing out the Arabs invented algebra before the Europeans
started using it, so the European mathematicians don't deserve any credit at
all.

Props to these guys and the entire denizens of Europe, if that makes you feel
more politically correct :)

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paulhart
Canada requires fuel economy figures in liters per 100km.

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mrdorian
So does China

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eru
And the rest of the civilized world.

(Sorry, I just like the SI system of units.)

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hugh
Actually I think the Imperial system is better in this case. I find it easier
to remember a number which is an integer in the 20-40 range than a real
between 5 and 10.

I find that in my mind, most of the relevant numbers tend to get rounded up to
"a bit less than ten" anyway.

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eru
Only for you - and only for the current state of efficencies.

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mynameishere
I still can't wrap my head around celsius. Is 20 celsius hot? Is 25 hot? I'm
not sure. I'd have to convert it to fahrenheit in order to get a feel.

Same thing. I know that 20 mpg is somewhat bad, 30 mpg is somewhat good. How
about... 0.05 gallons per mile? I'd have to divide it first. This is the
reason why grocery stores sometimes advertise prices at 4 dollars per 9 units,
and similar. They know people can't work out that math instantly...

~~~
Xichekolas
But like everything, if you use it for a little while you get an intuitive
sense for the numbers.

I used to struggle with celsius as well, but then I lived in Spain for a
while. Once I stopped converting to Fahrenheit all the time and just tried to
associate the numbers with days that I remember, I got where I know that 20 is
fresh, 25 is warm, 30 is getting toasty, and 42 is a smokin' hot summer day in
Sevilla.

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ROFISH
This is a solution looking for a problem. This just solves the 'I save exactly
x gallons' while most people just want to drive to work slightly cheaper.

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bkovitz
The problem is that "miles per gallon" gives you a false impression of your
costs and the fuel savings you get by switching to a more or less fuel-
efficient car.

This is likely not a problem that many U.S. citizens are _aware_ that they
have, though.

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pg
They're a lot more aware of it than they were a year ago.

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sosuke
I couldn't find one listing of a gallons per mile in the article.

<http://www.google.com/search?q=20+mpg+in+gallons+per+mile>

Is that correct for what they are looking for? My car gets .05 gallons per
mile! Wait the structure on that sentence is wrong isn't it?

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TheWama
They corrected for this in the tests:

> the tests were repeated using gallons __per 100 miles __

You could also say "aught-5 gallons per mile," where the decimal is placed by
convention. Though then you run into trouble with the .009 gpm cars...

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jgrahamc
My car shows me this on its onboard computer. It gives me instantaneous and
averaged litres per 100 kilometres.

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pierrefar
Yes, but will the car manufacturers actually do this? Sounds to me that it
could cost them some sales...

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Xichekolas
Only if gas guzzlers are more profitable than efficient cars, which, granted,
has been the case up until now. However, with so many companies trying to
differentiate based on green credentials now, it seems likely that their high
margin business will be in efficiency in the future.

So short answer: maybe.

