Since volume is equivalent to metres cubed and distance is equivalent to metres (both multiplied by some conversion coefficient), I think fuel efficiency should be measured in metres squared, because why not.
This is a correct unit for it. Why? Think of it like a tube where as you move along it you use up the fuel. Over a set distance you would use more in a lower efficiency vehicle. Since the length of that pipe is the same, then the change would be the area of the ends of the pipe. Thus fuel efficiency is an area, smaller is better.
Since volume is equivalent to metres cubed and distance is equivalent to metres (both multiplied by some conversion coefficient), I think fuel efficiency should be measured in metres squared, because why not.
This is a correct unit for it. Why? Think of it like a tube where as you move along it you use up the fuel. Over a set distance you would use more in a lower efficiency vehicle. Since the length of that pipe is the same, then the change would be the area of the ends of the pipe. Thus fuel efficiency is an area, smaller is better.
https://what-if.xkcd.com/11/
(Yes, the “bird poop” one is correct, it does talk about fuel consumption too).
I mean, you are correct in that there is an actual physical interpretation for it