Comment by jonas21

First of all, the most recent data in the document you linked to shows Amtrak at 1,629 BTU/passenger-mile vs 3,877 BTU/passenger-mile for cars -- a 58% reduction in energy consumption, or alternately 2.4x better energy efficiency for trains over driving.

But it's also important to note that the numbers for Amtrak are averaged across the entire system -- and most Amtrak routes outside the Northeast Corridor operate way below capacity, despite it being very inefficient to do so. If you look at rail systems where this is not the case, like in Switzerland (716 BTU/passenger-mile) or Japan (534 BTU/passenger-mile), you end up with 5.4x and 7.3x improvements energy efficiency over driving, respectively.

[1] https://en.wikipedia.org/wiki/Energy_efficiency_in_transport...