Why MPG and not MPL

The Running Man · 9 Dec 2018 at 18:15

Seeing as though we buy petrol and diesel by the litre, pay by the litre and understand the price per litre in a simple way...

Why don't we calculate miles per litre intead of to the gallon?

Now sure I could work it out by multiplying out the cost etc

But I can't just go to a petrol station knowing my car gets 10 miles to the litre and put in 10 litres of fuel knowing it should roughly get me 100miles if driving for instance at 10mpl...

Damn typo in thread title...

Hades · 9 Dec 2018 at 18:20

The country used to use the imperial measurement system. Petrol never fully moved over to the newer metric system because we were all used to gallons at the time. We should really use kilometers too but keep using miles for the same reason. But you are right it doesn't make sense to quote prices in one system and efficiency in another.

Miles Per Litre doesn't make any sense. If we did go full metric then it should be [EDIT] Kilometers Per Litre.

Personally I think we should completely move over to kilometers and litres nowadays.

Diagro · 9 Dec 2018 at 18:20

Just do the maths...

4.54L per gallon.

Not hard mate.

Minstadave · 9 Dec 2018 at 18:20

I guess mixing imperial and metric seems daft, even though that's what we do every daynin reality.

MPG or km/L.

snips86x · 9 Dec 2018 at 18:21

Diagro said:
Just do the maths...

4.54L per gallon.

Not hard mate.

Exactly how I work it out lol

Minstadave · 9 Dec 2018 at 18:21

Hades said:
Miles Per Litre doesn't make any sense. If we did go full metric then it should be Miles Per Kilometer.

Wut?

Hades · 9 Dec 2018 at 18:23

Minstadave said:
Wut?

Haha sorry I meant Kilometers Per Litre

MrRockliffe · 9 Dec 2018 at 18:49

Hades said:
Haha sorry I meant Kilometers Per Litre

Long week?

andy_mk3 · 9 Dec 2018 at 18:54

It's something people are used to and understand though. If someone says their car does 55MPG, pretty much everyone knows that's good.

Minstadave · 9 Dec 2018 at 18:55

andy_mk3 said:
It's something people are used to and understand though. If someone says their car does 55MPG, pretty much everyone knows that's good.

And if a manufacturer says their car does 80MPG you know they're lying

Rroff · 9 Dec 2018 at 19:00

Hades said:
Personally I think we should completely move over to kilometers and litres nowadays.

Personally I don't see the fascination with switching purely to one system or the other, etc. I find miles works much better for long journeys yet I switch to metres when getting closer to somewhere and likewise use cm/mm, metres, feet and inches mixed in many areas of life i.e. when decorating.

It isn't a particular attachment for one system or the other as I was brought up in an environment that used both daily.

Clarkey · 9 Dec 2018 at 19:32

Should go fully metric imo, imperial is ridiculous and needs to be consigned to history.

TallPaul_S · 9 Dec 2018 at 19:34

Hades said:
Haha sorry I meant Kilometers Per Litre

Don't the Europeans/Aussies use litres per 100km? I have literally no idea whether 5l/100km is good, only that the lower the number the better!

Don't get me started on kilowatts instead of BHP!!

Stusteel · 9 Dec 2018 at 19:40

My car reports L/100km.

Is a 270CDI and average about 5.8L/100km. I would have no idea on mpg.

D3K · 9 Dec 2018 at 19:44

Why even the letter 'P'?

Nothing else in engineering uses it. Gbps/Mbps maybe? Again, these are for the layman.

Bring back the '/' divisor

Scania · 9 Dec 2018 at 20:31

18mpg overall is pretty poor for me but given the car not too bad.

Compared to the 11mpg overall my 13.6 litre HGV gives me its dire but, an 18year old HGV would get nowhere near 11mpg so it’s all relative.

MPG sounds right, L/100km is meaningless to most.

The Running Man · 9 Dec 2018 at 20:32

Diagro said:
Just do the maths...

4.54L per gallon.

Not hard mate.

Yeah so why do the maths when they could just publish that number instead ?

Miles per gallon means nothing because we don't buy in gallons.

Meridian · 9 Dec 2018 at 20:41

Diagro said:
Just do the maths...

4.54L per gallon.

Not hard mate.

I think you missed the point? The question was not "how do you do it?", "why don't we do it?"

mjt · 9 Dec 2018 at 22:34

So most of Europe uses l/100km, yet Scandinavia uses km/l.

And in Sweden and Norway, a "mile" is 10km.

HangTime · 9 Dec 2018 at 22:42

Hades said:
The country used to use the imperial measurement system. Petrol never fully moved over to the newer metric system because we were all used to gallons at the time. We should really use kilometers too but keep using miles for the same reason. But you are right it doesn't make sense to quote prices in one system and efficiency in another.

Miles Per Litre doesn't make any sense. If we did go full metric then it should be [EDIT] Kilometers Per Litre.

Personally I think we should completely move over to kilometers and litres nowadays.

I disagree, measuring distances in miles is understandable because all the road signs etc are based on miles so there would be a massive overhead from converting to kilometres. Whereas on the fuel front, very little is done in exclusively in gallons (i.e. without litres), and it wouldn't cost much to move over to miles per litre.
I am not suggesting that we should rule out moving over to kilometres, but it is a much bigger change than adopting litres so I wouldn't want to group them in together.