Kilometers per liter (KMPL)

[petrolgeek]

Reviving the old request for kilometers per liter (KMPL) as an alternative to MPG.

In India, KMPL is the standard metric for fuel economy. Volume is measured in liters and distance in kilometers. Yet, no one recognizes the L/100km metric at all.

All auto manufacturers in India report only this metric and this is the accepted standard.

Can we hope to see KMPL as a metric anytime soon?

Thanks!

[pb]

Adding a new unit of measurement like this is sort of like adding a new gear to a transmission. It involves touching just about every file on the site, and adding hundreds of lines of code. We'll consider it, but it is something we'd need to dedicate some serious time to, so this likely won't be added in the near term.

I know this means the site isn't very useful to you, sorry about that. You might see if there are some similar applications built specifically for India.

[DTMAce]

Personally, I never understood the point of L/100K anyway. I always wondered WHY they never did do them in KMPL. That just makes more sense. But that was my opinion of course.

[ggarnier]

L/100k seems alien at first to someone who grew up with mpg, but in a way it makes more sense. It makes the concept of cost for a trip a bit more accessible mentally. If I know that I'll have to replace X numbers of liters after making a trip, I can more easily assess the cost/benefit of the trip.

[DTMAce]

Errr... Ok.

So dividing total trip Kilometers by 100 then multiplying that by the L/100K value to get how many liters for your trip is easier than dividing total trip miles by the avg MPG to see how many gallons it takes? (or the same of KMPL) Sounds like more steps, according to the math.

Maybe its easier due to having a 100k value as part of the division path, but from a step point, it takes two steps, instead of one.. That or I'm missing something simple.

If you are using this to plan a budget for before you take a trip is what I'm assuming here.. But I always budget for 1.5 times what I need. Cause ya never know how many side jaunts or missed turns you may take. lol

But oh well. Still think its just.. Odd, regardless of the reason.

[petrolgeek]

I agree it is a matter of what one is accustomed to. For instance:

Suppose my car does 8.7 L/100k which is the same as 11.5 kmpl. So what would be the estimated amount of fuel for a 65km trip?

* Using L/100k: Fuel = 65 * 8.7 / 100 = 5.65L

* Using kmpl: Fuel = 65 / 11.5 = 5.65L. To get a rough estimate, it is easy to see that 65/11.5 ~ 6L. I find this easier. But then again, I have been using kmpl forever, so find this easier.

Anyway, would be good to see kmpl being the default if one has selected India as the country of residence.

[ggarnier]

First let me say I was never pushing for the L/100km option myself, and since pb has explained what would be involved, I never would.

And I'll give it to DTMAce that my argument was weak.

[DTMAce]

Ah no worries there gg. Just me ole' American brain not wrapping around it I think. As for the site, yeah, a lot of work would be involved, but it would be a cool thing to have here.

[pb]

We do support L/100km across the site, ggarnier, you just need to switch to the "metric" view to see it. It's a standard in many places including Europe, China, Canada, Australia and New Zealand—according to Wikipedia's article on Fuel Economy. We have a special UK view because the gallons are a different size and they sell fuel in liters.

And according to the wikipedia article on Fuel efficiency India and Japan use km/L. We honestly didn't know that when we set up the site, and we heard from more UK and Canadian folks during the early building phases of the site. That's why we have MPG and L/100km but not km/L. We've had a few requests for km/L and it is something we'd do in a perfect world, it will just depend on whether or not we can devote the time to it.

[jostlehim]

One reason for using l/100km is that it makes it easier to compare efficiencies and the relative improvement from increases in efficiency.

As an example, 25mpg (US) is 9.4 l/100km, 30mpg is 7.8 l/100km and 35mpg is 6.7 l/100km

Looking at the values in miles per gallon, there is 5mpg difference between 25->30 and 30->35. However, in l/100km it is clearer that the improvements between the two efficiencies are different:

9.4-7.8=1.6

7.8-6.7=1.1

Thus you can see that the move from 25mpg->30mpg makes a bigger difference to your fuel consumption than the move from 30mpg->35mpg.

20mpg (11.8) -> 30mpg (7.8) is a difference of 4l/100km (10 mpg)

30mpg (7.8) -> 50mpg (4.7) is a difference of 3.1l/100km (20 mpg)

Using volume/distance makes it slightly easier to compare the efficiencies of cars and to work out how significant the differences are.