Fuel consumption - why MPG?

CiniO

Ireland went through good few changes in the past years.
One of them was changing speed limits from MPH to km/h, also all distances are shown now in km instead of miles. Car speedometres and odometres show in km now. Also on petrol stations we buy fuel in litres, not in gallons.

Considering all this, when it comes to fuel consumption, why do people still use MPG instead of l/100km.

In exception from cars that have built in onboard computers, it's awfull difficult to count it, as car doesn't show miles, and a pump on petrol station doesn't show gallons.

Everywhere over Europe (except from UK, l/100km is used).

Calculation is extremally simple. Just lets say you filled the tank to the top, driven for 650km, and filled it again. Let's say 45 litres of pertrol went it it.
You just divide a number of litres, by number of hundreds of kilemetres travelled.
In this case 45/6.5 = 6.92

And that's the fuel consumption. 6.92 litres per 100km.

I don't even want to think, how much counting should be done to get this score in miles per gallon.

af_thefragile

Because its easier to compare with other cars...

Like you know a VW Polo Bluemotion can do 80mpg which is really good and a Lamborghini Murcielago can do 8mpg which is not very good.
So if your car does 30mpg, its easier to compare rather than converting all the figures to litres/100km and it gets all messy...

CiniO

af_thefragile wrote: »

Because its easier to compare with other cars...

Like you know a VW Polo Bluemotion can do 80mpg which is really good and a Lamborghini Murcielago can do 8mpg which is not very good.
So if your car does 30mpg, its easier to compare rather than converting all the figures to litres/100km and it gets all messy...

I'd ask in the first place - how do you know that VW Polo does 80mpg and Lamborghini does 8mpg?
I'm sure all these figures are the same available in litres/100km

Litres / 4.54 = gallons.
Miles / gallons = mpg

It's hardly first principles or Einstein's laws of motion is it.

unkel

CiniO wrote: »

when it comes to fuel consumption, why do people still use MPG instead of l/100km

It's gonna take a while to wean ourselves off the Imperial system of measurement from Great Britain, in favour of the metric system.

We'll get there at some point

In the meantime it's handy if you can think in both systems when you're living in this country - and sometimes have to talk to old people

af_thefragile

CiniO wrote: »

I'd ask in the first place - how do you know that VW Polo does 80mpg and Lamborghini does 8mpg?
I'm sure all these figures are the same available in litres/100km

Probably cuz I spend a significant amount of time watching and reading Top Gear... But I guess its because of the brits and the americans (although the americans use a different gallon to the brits) that mpg has become sorta a standard for measuring fuel consumption in the english speaking world...

CiniO

RoverJames wrote: »

Litres / 4.54 = gallons.
Miles / gallons = mpg

It's hardly first principles or Einstein's laws of motion is it.

OK, that's right - it's not complicated maths.
Anyway - it's still much easier to use l/100km

CiniO

unkel wrote: »

It's gonna take a while to wean ourselves off the Imperial system of measurement from Great Britain, in favour of the metric system.

We'll get there at some point

In the meantime it's handy if you can think in both systems when you're living in this country - and sometimes have to talk to old people

I know that. And I do try to know both measures.
Anyway, while km are getting better and better - i see lot's of Irish people using km as a distance measure instead of km, then i didn't meet anyone who would use l/100km instead of mpg


Also litres came in great, no one really think in gallons anymore.
Pints still work (in bars mostly) - but that's good because it better to get a pint of bear instead of 500ml ;P

CiniO

af_thefragile wrote: »

Probably cuz I spend a significant amount of time watching and reading Top Gear... But I guess its because of the brits and the americans (although the americans use a different gallon to the brits) that mpg has become sorta a standard for measuring fuel consumption in the english speaking world...

That's also very interesting matter.
American MPG are different to British MPG.

PS. I don't think the can be something like standard for english speaking world. If Ireland decided to switch to metric units, then it should go with everything, not leaving that kind of traces like MPG, which is based totally on imperial units.

af_thefragile

If you read British car magazines/tv shows, they use MPGs when reviewing cars and as we don't have any decent car magazines/shows here in Ireland and as can't understand what the rest of Europe is saying, hence we've got to go with the Brits for the time being...

It is a bit tricky though when trying to calculate the mpg, cuz first you've got to convert the litres in to gallons by dividing it by 4.5 or something. Then as my car is an old car, it gives the mileage in miles rather than Kms so another reason why I use MPG.

ShiresV2

CiniO wrote: »

I don't even want to think, how much counting should be done to get this score in miles per gallon.

282 / litres_per_100_km = imperial_miles_per_gallon

Easy!

Big Nasty

I like MPG, LPK doesn't do anything for me. I guess I'll have to get used to it at some stage and it will become natural. Much like when the euro came out: 'What's that in real money?' - 9 years on I don't do that no more.

sentient_6

My car is all in kilometers & the fuel consumption is in L/100km. All our signs are in km, our pumps in litres. So its very simple for me anyway. But when reading threads on here & such i find myself using an online converter to switch to MPG cos everyone on here for the most part still goes by that. Sometimes i wonder though when i see people complaining there only getting MPG in the 20's do they realise it might be U.S gallons not UK....but thats an aside. It will take another ten years or more maybe to completely weed out the imperial system.

By the way i think the change will come as older cars are gotten rid of & people start driving cars that are only metric. I.e in what people think in.

stealthyspeeder

What are these litres and kilometres you speak of?

Matt Simis

MCMLXXV wrote: »

I like MPG, LPK doesn't do anything for me. I guess I'll have to get used to it at some stage and it will become natural. Much like when the euro came out: 'What's that in real money?' - 9 years on I don't do that no more.

Well, pick some ballpark figures in "l/100km" to get some sense of perspective, it helps visualise.

Ie:
10l/100KM = 28mpg
5l/100km = 56mpg
or
40mpg is 7.1mpg
15mpg is 18.8L/100Km

On a normal run my 8 series is at 15.7L/100km and on a run in 6th it gets down to 13L/100km. For a normal car you really want less than 10L/100km consumption Urban.


Calcs here:
http://fuel.netcessible.com/FuelUK/FuelUK.htm

unkel

CiniO wrote: »

Pints still work (in bars mostly) - but that's good because it better to get a pint of bear instead of 500ml ;P

A litre of beer in Germany is cheaper than a pint of beer here

stealthyspeeder wrote: »

What are these litres and kilometres you speak of?

Go back home to your beloved queen

P.C.

af_thefragile wrote: »

Probably cuz I spend a significant amount of time watching and reading Top Gear... But I guess its because of the brits and the americans (although the americans use a different gallon to the brits) that mpg has become sorta a standard for measuring fuel consumption in the english speaking world...

It is not a 'sandard for measuring fuel consumption in the english speaking world'.

I grew in an english speaking country, and grew up with l/km.

When somone talks about MPG - I do not have a clue what they are talking about.

CiniO

unkel wrote: »

A litre of beer in Germany is cheaper than a pint of beer here

It's not a matter of price.
I just love when going to bar in Ireland I get a pint glass which is absolutely full. It's that full that there's no chance I can carry it back to the table without spilling.

Wherever else, you get 0.5l beer in a glass, and there's like 1/6 of the glass empty.

It's not about price - it's about climate that's in Irish bars - you won't get that anywhere else over the world.

Matt Simis

P.C. wrote: »

I grew in an english speaking country, and grew up with l/km.
:

Canada, NZ or Oz?

P.C.

Matt Simis wrote: »

Canada, NZ or Oz?

None of those.

Fishtits

Interesting question, I live my life work/home etc through metric yet still use MPG when it comes to consumption.

Maybe Litres per 100Km should be Km's per Litre? Its a bit more understandable for your average driver?

Mimikyu

This post has been deleted.

Del2005

I don't bother with either. I fill it when it gets low, I don't do big mileage.

What's the metric for mileage?

slimjimmc

Times are a changing and l/100km is getting more common. Quite a few of my friends with newer cars use l/100km because that's what their cars display. The rest of us with ye olde cars use mpg because that's what our cars display, and strangely a few others work in €/fill with absolutely no idea of the price per litre at the pumps.

IF you pay attention to any tv, radio or print advert or if you look up any brand's website you'll find that they quote l/100km instead of mpg, when they are targetting the Irish market.
For example

pajo1981

It's just a question of what people are used to, i guess?

imo as more and more cars are fit with l/100km based trip computers, more people will think in terms of l/100km

slimjimmc

To be fair though "mpg" does roll off the tongue a lot easier than "L per 100 k" or "L slash 100 k". Maybe we should change it to
lphk : Litres Per Hecto Kilometre or Litres Per Hundred Kilometre
or just
lph : : Litres Per Hundred (the Kilometre implied)

Matt Simis

Fishtits wrote: »

Interesting question, I live my life work/home etc through metric yet still use MPG when it comes to consumption.

Maybe Litres per 100Km should be Km's per Litre? Its a bit more understandable for your average driver?

That would be bad.
There is an inherent confusion over Miles Per Gallon and "Kilometers per Litre" due to the fact they do not incorporate a usage over time metric:
http://wheels.blogs.nytimes.com/2008/06/20/the-illusion-of-miles-per-gallon/
http://www.google.ie/search?q=mpg+illusion&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

There is a big push in the US to switch to GPM (Gallons per 100 Mile), switching to KPL would be a big step backwards for us. The EU standard is L/100KM (and is becoming the international standard too), it absolutely is the best measurement. As someone already stated, you put in fuel in litres, you drive 500 kilometers, how many kilometers did I drive on 60litres of fuel expressed as L/100km is 60/5 (hundreds of km) = 12L/100km.

SpannerMonkey

i use mpg and so do most people id imagine purely because nearly all english speaking countries use it and its what we are exposed to in the media , magazines papers and on tv they all use mpg unless its an irish one and then everyone is just confused

baalthor

davy_b wrote: »

i use mpg and so do most people id imagine purely because nearly all english speaking countries use it and its what we are exposed to in the media , magazines papers and on tv they all use mpg unless its an irish one and then everyone is just confused

Most English speaking people use MPG (and its not the same 'G' !)

Of English speaking countries, I can only think of two (US, UK) that officially use MPG.

Henry Ford III

MPG works just fine thanks very much

SpannerMonkey

baalthor wrote: »

Most English speaking people use MPG (and its not the same 'G' !)

Of English speaking countries, I can only think of two (US, UK) that officially use MPG.

i am aware of that but the us and uk account for the largest percentage of population of english speaking people and mpg is what we are used to, and what we read in most auto mags etc that we get here as they are mostly mags from the UK so it will not fade out easily

pajo1981

Henry Ford III wrote: »

MPG works just fine thanks very much

dublin to galway 200km.

Your trip reports you're averaging 6l/100km.
how much fuel are ye gonna use?
12liters

A child could do it.

Repeat using MPG...

Mimikyu

This post has been deleted.

mb1725

Lots of people use the financial yardstick (sorry) of km/euro or miles/euro as that's what counts at pump.

Henry Ford III

pajo1981 wrote: »

dublin to galway 200km.

Your trip reports you're averaging 6l/100km.
how much fuel are ye gonna use?
12liters.....

Mighty

I'm only concerned with 2 issues regarding fuel:

1/. Is the car running economically and properly? My mpg reading will tell me that.

2/. When do I need to refill? My fuel gauge will tell me that.

The amount of fuel used isn't therefore too important I'd suggest.

Del2005

mb1725 wrote: »

Lots of people use the financial yardstick (sorry) of km/euro or miles/euro as that's what counts at pump.

1st time I've ever heard that mentioned. It isn't very easy to compare cars thought as there are too many variables involved.

I think the reason one of the reasons why MPG is still used is that a big number sounds better then a small number. What sound better in the bragging stakes "I got 5l/100km" or "I got 56mpg"?

Stinicker

What kind of fool came up with l/100km in the first place it is so much easier to visualise MPG, KPL (Kilometres per Litre) would be the proper way to measure fuel consumption in the metric world.

pajo1981

Stinicker wrote: »

What kind of fool came up with l/100km in the first place it is so much easier to visualise MPG, KPL (Kilometres per Litre) would be the proper way to measure fuel consumption in the metric world.

stikner, consumption is directly proportional to l/km and inversely to mpg. Surely it's best to keep things simple?

Esel

mb1725 wrote: »

Lots of blond people use the financial yardstick (sorry) of km/euro or miles/euro as that's what counts at pump.

FYP

mb1725

She still gets 100 miles per 20 euro!!!

steve french

i still go by mpg and i even convert speed signs back to mph in my head.

Wibbs

steve french wrote: »

i still go by mpg and i even convert speed signs back to mph in my head.

As do I but I'm old. TBH I think of money. How many quid/euros* will a journey cost and how much distance I get to a tank. Litres or gallons doesnt really concern me. Though like I said I grew up with gallons so I know on a long run taking it easy I get 40 odd miles per gallon. Having grown up between the two posts as it were, I use diff measurements for different things. I massively prefer mm over 4/16ths of an inch or any of that nonsense. I tend to think in inches more than cms and I defo use feet. The metric system is seriously lacking a useful measurement between cms and metres. A third of a metre?eh no. bugger off. Miles Kms not such an issue.









*Yes I add the s, Im not French. Euro = singular. Euros - plural.

CiniO

baalthor wrote: »

Of English speaking countries, I can only think of two (US, UK) that officially use MPG.

And even more - they are different MPG in US and different MPG in UK.

D_murph

steve french wrote: »

i still go by mpg and i even convert speed signs back to mph in my head.

Same here. 200Kms = 125 miles to me etc. But thats just probably me being old fashioned .



"My Car Gets 40 Rods To The Hogshead, And That's The Way I Likes It!"

:pac:.

Matt Simis

Stinicker wrote: »

What kind of fool came up with l/100km in the first place it is so much easier to visualise MPG, KPL (Kilometres per Litre) would be the proper way to measure fuel consumption in the metric world.

If you would care to read instead of deriding those "fools" that put a lot more thought into measurement systems than you, to quote myself only one page ago:

There is an inherent confusion over Miles Per Gallon and "Kilometers per Litre" due to the fact they do not incorporate a usage over time metric:
http://wheels.blogs.nytimes.com/2008/06/20/the-illusion-of-miles-per-gallon/
http://www.google.ie/search?q=mpg+illusion&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

There is a big push in the US to switch to GPM (Gallons per 100 Mile), switching to KPL would be a big step backwards for us. The EU standard is L/100KM (and is becoming the international standard too), it absolutely is the best measurement. As someone already stated, you put in fuel in litres, you drive 500 kilometers, how many kilometers did I drive on 60litres of fuel expressed as L/100km is 60/5 (hundreds of km) = 12L/100km.

Just cos you "know" of a system using distance per unit of measurement doesnt mean its good or better. How sadly commonly short-sighted is that?

These conversations tend to drift away from the sound logic that L/100km bears to a xenophobic fear of something new, like arguing with the metric martyrs in the UK. L/100KM is, by far, the most appropriate measurement system to use here. There is no logical reason to not use it other than familiarity with the flawed and redundant system in place and unwillingless to use your brain to learn something beneficial.

Esel

Apart from the very many thousands of drivers whose odometer shows miles, not kilometres.....

mad m

Slightly OT but in the US, is there gallon classed as 4litres or 4.5litres as opposed to 5litres is a gallon here?

Del2005

mad m wrote: »

Slightly OT but in the US, is there gallon classed as 4litres or 4.5litres as opposed to 5litres is a gallon here?

1 US gallon = 3.785l
1 UK gallon = 4.546l

http://www.convert-me.com/en/convert/volume

SpannerMonkey

D_murph wrote: »

"My Car Gets 40 Rods To The Hogshead, And That's The Way I Likes It!"

:pac:.

:eek:thats pretty crap mate considering 40 rods is equal to roughly 0.20 Kilometers and one hogshead is roughly 238.5 litres of fuel,:D. yup i am actually that bored that i looked it up