Trains transports at 0.41 MJ/t·km. If the person weights 0.1t it would take a train packed full of people 41MJ per person to transport them 100km, or a bit more than one litre of gasoline. I don't think it is possible to go significantly below that without transporting them on mag rails or vacuum pipes.

Secondly we talked about 0.005l cars, not 0.05l, so it would be a few hundreds times more efficient than train transportation.