Personal rapid transit

[Thue]

Personal rapid transit (PRT) is an alternative to cars and railroads. Very cool, could be the future of land transport. I don't understand why it isn't being pushed more. Try reading this article: http://www.spiegel.de/international/...458893,00.html

Basically this is building (possibly elevated/buried) rail everywhere, and running small (down to 1-person) computer-controlled "taxis" on it. The system is switched such that you just call a "taxi", and is then taken directly to your destination without changing cab.

The advantages to an electrical, city-elevated, automated PRT system over cars as I see them
1) As it is electrical it will not pollute in the middle of the city. And if the electricity is generated by nuclear or renewable it will not pollute at all.
2) Traffic deaths, which is a major cause of death and injury today, will be heavily reduced
3) A computer-optimized traffic control system would presumably make coordinating transit more effective (see article).
4) Cars, both parked and in transit, will no longer clog up the streets, so large parts of cities could be car-free. The streets can then be reclaimed for other purposes. That would make the 20th century an interlude where city streets were dominated by cars.
5) Freight can be delivered directly from the sender to the receiver, making trucks obsolete.

http://en.wikipedia.org/wiki/Personal_rapid_transit

[LordShiva]

If one of them breaks down on the track, the entire city is screwed.

[Thue]

No, because they are build on a grid, so other cars can just be routed around.

Just like network packages. The internet does not go down because a single line in the network quits.

[Spiffor]

Re: Personal rapid transit

Originally posted by Thue
I don't understand why it isn't being pushed more.

I do:

Basically this is building (possibly elevated/buried) rail everywhere

There's a project currently in Paris suburbs to make a new buried subway line. A fast High-traffic one. It costs 90 million € a kilometre. That's quite a bit of money. Now, for PRT to work, you don't need a single line, but rail everywhere, and crossings everywhere (crossings take quite a bit of room), so imagine just how much that would cost.

[SlowwHand]

If you don't have the traffic, you don't need the roads either. What are we going to do with all these roads?
We'll have to tear them up. It will have to be planned so that it's not like painting yourself into a corner. Which is another thing. What about the road deconstruction equipment, after they've torn out the roads? Just park where they've been planned to stop? Then do what? Art as a historical display?

[LordShiva]

Originally posted by Thue
No, because they are build on a grid

That would be extremely expensive and ugly.

And we're talking about tens of thousands of little private cabs here, without the ability to pass each other (since they're on a rail, not a road).

[LordShiva]

Originally posted by SlowwHand
What are we going to do with all these roads?
We'll have to tear them up. It will have to be planned so that it's not like painting yourself into a corner.

I never thought of that.

[Spiffor]

Originally posted by SlowwHand
If you don't have the traffic, you don't need the roads either.

[Thue]

Originally posted by LordShiva


That would be extremely expensive and ugly.

And we're talking about tens of thousands of little private cabs here, without the ability to pass each other (since they're on a rail, not a road).

They will be going at the same speed, so of course they don't need to pass each other. Off-rams would be used for start/end-points.

[Thue]

Originally posted by SlowwHand
If you don't have the traffic, you don't need the roads either. What are we going to do with all these roads?
We'll have to tear them up. It will have to be planned so that it's not like painting yourself into a corner. Which is another thing. What about the road deconstruction equipment, after they've torn out the roads? Just park where they've been planned to stop? Then do what? Art as a historical display?

Are you by any chance an American?

At least here in Copenhagen, space freed up roads could be used for walking, recreation, or just green areas. You could actually use the old roads as social space, with children running around etc.

[Will9]

They'll all be tralaling at the same high speed so is no need to pass eachother.

Edit: I read the article then when I came back I forgot to refresh the page and I thought LordShiva's post was the last one.

[Thue]

Re: Re: Personal rapid transit

Originally posted by Spiffor


I do:

Basically this is building (possibly elevated/buried) rail everywhere

There's a project currently in Paris suburbs to make a new buried subway line. A fast High-traffic one. It costs 90 million € a kilometre. That's quite a bit of money. Now, for PRT to work, you don't need a single line, but rail everywhere, and crossings everywhere (crossings take quite a bit of room), so imagine just how much that would cost.

It will have to be cheaper than that, of course. 90M€/km seems like a loot, it must be possible to do it cheaper.
Burying many meters underground has to be very expensive. I am guessing that making it elevated has to be cheaper.

The article mentions that running a PRT system instead of the current railway system on the current rails we use today would be cheaper than the current trains.

[SlowwHand]

Originally posted by Thue


Are you by any chance an American?

At least here in Copenhagen, space freed up roads could be used for walking, recreation, or just green areas. You could actually use the old roads as social space, with children running around etc.

Sterling dissertation on life in Copenhagen.
Do the people of Copenhagen understand raper-like wit?
Apparently not.

[Spiffor]

Re: Re: Re: Personal rapid transit

Originally posted by Thue
It will have to be cheaper than that, of course. 90M€/km seems like a loot, it must be possible to do it cheaper.
Burying many meters underground has to be very expensive. I am guessing that making it elevated has to be cheaper.

Elevated costs also huge heaps of money. Basically, you have to buy land like crazy. And build a bridge under each and every rail. And considering how intensive the rail should be for the system to work, the city will soon have a ceiling made of rail.

Generally speaking, I fail to see the difference between PRT and some kind of futuristic cars (electricity-powered and on autopilot), except that PRT requires a humongous infrastructure that isn't there and just can't be.

[LordShiva]

Originally posted by Thue
They will be going at the same speed, so of course they don't need to pass each other.

But the problem arises when one of them breaks down and the guys behind can't get by. It' fine if there's a grid, but that doesn't help the people behind the broken down car.

And also, since we're talking about thousands of cars here, whenever a car needs to get on to a main track from an on-ramp, all the others will need to slow down, and this "wave" will be propagated back throughout the entire network, for each car.