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by tschuy 3081 days ago
Transatlantic flights average 75 mpg per passenger, but can be up to almost 100 mpg per passenger:

https://en.wikipedia.org/wiki/Fuel_economy_in_aircraft

Jet fuel is 37.4 MJ/L; compare to gasoline at 34.2:

https://en.wikipedia.org/wiki/Energy_density#Energy_densitie...

An electric car will have up to 150 miles-per-gallon equivalent (aka 150 miles per the same amount of energy that's in one gallon of gasoline):

https://en.wikipedia.org/wiki/Miles_per_gallon_gasoline_equi...

So therefore, an electric car with just the driver is more efficient energy-wise than an airplane, while an average airplane is better than a gas car with even three people in it.

2 comments

You already started along the road to normalisation by using MJ/L but you might as well go the whole way and consider absolute cost per person per mile... or person miles per absolute unit cost if you prefer. Those might be more telling figures.

For instance many EV proponents note the total cost of ownership difference due to significant differences in maintenance costs. Playing the other side of the argument: they tend to forget about the value of upfront cost is more than later cost.

It's still possible to achieve some sort of quantitative comparison by applying an interest rate based on "distance" of the cost in time before summing them. If you applied this to a regular petrol car you might be able to make a better comparison to the ticket price of a flight.

Dunno, a modern UK car will get 60mpg on motorway travel (that's what I've had), or even more. that's 50miles per us gallon. 2 passengers means 747 fully loaded efficiency, 3 wipes the floor.

Of course a 747 in a domestic Japan configuration will have more passengers than a typical BA 747 tatl flight with 100+ beds.