alt Hacker NewsTrains are expensive because the track is 99.9% empty.
If you could fill a train track as much as a road is filled, it would be very cheap
Trains are expensive because the track is 99.9% empty.
If you could fill a train track as much as a road is filled, it would be very cheap
Track utilisation is limited by a number of factors, including headways, much of which is governed by stopping distance.
I believe a general minimum practical headway allows about 10--12 trainsets per hour on a given track. At 400 passengers/trainset, that's roughly 4,000 to 4,800 passengers/hour, per track.
That compares with about 1,500 vehicles/hour per highway lane, or about 2,550 passengers/hour at the U.S. average of 1.7 passengers/vehicle.
I've seen some suggestion that headways could be reduced to 3--4 minutes, or 15--20 trainsets/hour. I know that some urban rapid transit systems (e.g., BART in San Francisco) achieve this, but only on a small section of the system (Colma to Oakland, transiting downtown SF, IIRC). Train speeds there peak at 70 MPH, and I believe are much slower for most of this portion of track.