The rolling resistance of steel wheels on steel rails is much, much lower than rubber tyres on an asphalt road.

From [1], the only comparable figures are the American train and the American bus. The bus is about half as efficient as the train.

There are similar figures further down the page ("German environmental costs") -- 0.25MJ/passenger-km for long distance rail, 0.85MJ/pkm for regional rail, 1.14MJ/pkm for bus service.

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