so I make his effective fuel consumption about 77mpg.
Yes I agree with your calculation.
But as car drivers we are I think collectively locked into the 'mpg mindset' and this example just shows how misleading that can be. I'm still pleased with 78mpge, but if I'm honest at first I felt a little bit deflated after the smug satisfaction of achieving so many miles on one tank and a headline near 200mpg.
To make a real comparison between cars with differing means of propulsion we need a more universal unit of measurement. Mpge might do for now as it feels comfortingly close to what we are used to.
But why do we need to bother converting all fuel cost to the equivalent of a gallon of fossil fuel? Why not convert the cost of petrol to electrical equivalent and quote miles/kwhe? It's equally as logical, or illogical perhaps.
Cost per mile (or Km) seems to me eminently more sensible.
This is not directed ay any of the posters on this thread or any other. More a rhetorical question which may or may not strike a chord with others. :ugeek: