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Old June 13th, 2008, 03:44 AM   #41
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That would be no different from PRT in the same corridor, or any other system. You're also trying to compare costs with a tunnel to costs without a tunnel, AGAIN. Stop using location-specific costs to mislead people about the difference between systems. Stop being dishonest.
About 2 miles of the Largo Town Center extension of the Washington Metro are in a cut and cover tunnel.

Stop making blind assertions without any supporting data that light rail is always cheaper than other systems. The Central Link light rail line under construction in Seattle demonstrates that light rail is just as expensive as a heavy rail metro when it is built along a route that requires extensive use of tunnels and viaducts.
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Old June 13th, 2008, 04:15 AM   #42
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Wow. Do people actually believe what they say even if it's nonsense? GIGO.

One second headways? You'll need to ensure that people can exit and enter a capsule in less than 0.5 seconds. An 80 year old granny with crutches will throw the entire system into chaos...

The Morgantown PRT system is successful? Most of the ridership is captured: students and staff and faculty with no other choice. If they were using a shuttle bus instead then ridership numbers would be similar and it would be an argument for anti-rail/all-bus types instead.

Only PRT is immune to high fuel prices? Last time I checked, so are streetcars, electric trolleys, metros, light rails, and biofuel buses (though not the food-to-fuel schemes).

And what about the fact that PRT is an invitation to spray graffiti, scratch the glass, puke, have kinky sex, and so forth? Can anyone imagine the depreciation rates?
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Old June 13th, 2008, 04:35 AM   #43
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No one is seriously suggesting building BRT anywhere anymore. It's hardly a "threat" here on the west coast, with nearly $5/gallon diesel. King County Metro's "Rapid Ride BRT" service improvements simply disappeared - they're talking the talk, but adding no new service.
There are several BRT projects underway in the Puget Sound region.

In Everett there is the Swift Bus project < http://www.everettwa.org/default.aspx?ID=1192 >. It will operate along Highway 99 between Everett Station and the Aurora Village Transit Center.

King County is in the process of developing several RapidRide bus routes < http://www.metrokc.gov/kcdot/transitnow/rapidride.stm >. The voters approved funding for the RapidRide system and other bus service improvements in 2006. The RapidRide service is expected to begin in 2010. The routes are as follows:

- Aurora RapidRide—Aurora Avenue N (SR-99) between Shoreline and downtown Seattle
- Ballard/Uptown RapidRide—Ballard to downtown Seattle along 15th Avenue NW and W Mercer Place
- Bellevue-Redmond RapidRide—Bellevue to Redmond on NE Eighth Street and 156th Avenue NE via Crossroads and Overlake
- Pacific Highway South RapidRide—SeaTac to Federal Way on Pacific Highway S (SR-99)
- West Seattle RapidRide—West Seattle to downtown Seattle using the downtown Seattle transit tunnel or Third Avenue.

There is no question that these projects will be built. The major question is the degree to which they will be true Bus Rapid Transit. There is a tendency for BRT projects to lose key features such as off-vehicle fare payment, traffic signal priority, and restricted access travel lanes.

I would not be surprised if there are other BRT projects underway in the Puget Sound region. These projects often do not require large sums of money and can be implemented by transit agencies without requiring referendums to provide new taxes.
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Old June 13th, 2008, 04:54 AM   #44
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...

And what about the fact that PRT is an invitation to spray graffiti, scratch the glass, puke, have kinky sex, and so forth? Can anyone imagine the depreciation rates?
Please remember that there is no driver in the second car of a two-car light rail train. I have seen grafitti and scratched glass on conventional trains. I remember watching a young lady puke on the seats on a light rail train in Boston. In New York, I remember seeing a young gentlemen go between the cars to urinate while the subway train was between stations. I can't claim that I have seen sex on a subway or light rail train, but I remember hearing somebody brag about doing it late at night on BART. None of these problems are unique to PRT.
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Old June 13th, 2008, 07:32 AM   #45
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Originally Posted by greg_christine View Post
There are several BRT projects underway in the Puget Sound region.

In Everett there is the Swift Bus project < http://www.everettwa.org/default.aspx?ID=1192 >. It will operate along Highway 99 between Everett Station and the Aurora Village Transit Center.

King County is in the process of developing several RapidRide bus routes < http://www.metrokc.gov/kcdot/transitnow/rapidride.stm >. The voters approved funding for the RapidRide system and other bus service improvements in 2006. The RapidRide service is expected to begin in 2010. The routes are as follows:

- Aurora RapidRide—Aurora Avenue N (SR-99) between Shoreline and downtown Seattle
- Ballard/Uptown RapidRide—Ballard to downtown Seattle along 15th Avenue NW and W Mercer Place
- Bellevue-Redmond RapidRide—Bellevue to Redmond on NE Eighth Street and 156th Avenue NE via Crossroads and Overlake
- Pacific Highway South RapidRide—SeaTac to Federal Way on Pacific Highway S (SR-99)
- West Seattle RapidRide—West Seattle to downtown Seattle using the downtown Seattle transit tunnel or Third Avenue.

There is no question that these projects will be built. The major question is the degree to which they will be true Bus Rapid Transit. There is a tendency for BRT projects to lose key features such as off-vehicle fare payment, traffic signal priority, and restricted access travel lanes.

I would not be surprised if there are other BRT projects underway in the Puget Sound region. These projects often do not require large sums of money and can be implemented by transit agencies without requiring referendums to provide new taxes.
Ugh, they have NO MONEY. Metro is talking about cutting service right now because of fuel costs. All they're doing is rebranding existing service.
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Old June 13th, 2008, 07:38 AM   #46
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Originally Posted by greg_christine View Post
About 2 miles of the Largo Town Center extension of the Washington Metro are in a cut and cover tunnel.

Stop making blind assertions without any supporting data that light rail is always cheaper than other systems. The Central Link light rail line under construction in Seattle demonstrates that light rail is just as expensive as a heavy rail metro when it is built along a route that requires extensive use of tunnels and viaducts.
!?!?!?!

I'm not talking about the Washington Metro, I'm talking about your comparison of PRT costs for elevated and at-grade, not including right of way, to light rail costs for tunneled, elevated and at-grade, including right of way and adjacent utility and roadway reconstruction.

You already know that Link was voted down the year before as a heavy rail metro. I've told you this several times, and you still just can't accept it.

You're incredibly dishonest in every conversation we've had about transit and transportation. You feign confusion and deliberately pretend I've said things I haven't in order to appear right. The crazy thing is that you really do seem to think you're being rational.

Frankly, I think people like you are part of the reason we have such a hard time getting transit built. Every person like you out there confuses dozens of others who don't have the time or energy to sort out your deception, so we end up with FUD killing projects right and left.
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Old June 13th, 2008, 07:39 AM   #47
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Wow. Do people actually believe what they say even if it's nonsense? GIGO.

One second headways? You'll need to ensure that people can exit and enter a capsule in less than 0.5 seconds. An 80 year old granny with crutches will throw the entire system into chaos...

The Morgantown PRT system is successful? Most of the ridership is captured: students and staff and faculty with no other choice. If they were using a shuttle bus instead then ridership numbers would be similar and it would be an argument for anti-rail/all-bus types instead.

Only PRT is immune to high fuel prices? Last time I checked, so are streetcars, electric trolleys, metros, light rails, and biofuel buses (though not the food-to-fuel schemes).

And what about the fact that PRT is an invitation to spray graffiti, scratch the glass, puke, have kinky sex, and so forth? Can anyone imagine the depreciation rates?
These people are simply insane, I'm afraid.
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Old June 13th, 2008, 09:10 AM   #48
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These people are simply insane, I'm afraid.
This is the typical anti-PRT response: they can't attack the research or the facts (which are solid) so their only recourse is ad-hominem attacks.

UrbanBen, do you care to respond intelligently to any of my earlier comments, or are you just going to call me insane?

I'll repeat: PRT is more efficient, more convenient, more accessible, more available, more cost effective, and less polluting than rail for most applications. I can point you to dozens of peer reviewed research papers which establish these facts - facts which have never been refuted in any published analysis.

Add to that the PRT development activity on three continents plus endorsements from New Urbanists Peter Calthorpe and Sir Peter Hall, renowned architectural firm Foster and Partners, MIT, Rutgers, and many other respected authorities.

Are they all crazy too?
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Old June 13th, 2008, 09:32 AM   #49
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Add to that the PRT development activity on three continents plus endorsements from New Urbanists Peter Calthorpe and Sir Peter Hall, renowned architectural firm Foster and Partners, MIT, Rutgers, and many other respected authorities.
Universities as a whole never endorse something. It goes against their mandate. Maybe a professor endorsed it, but that's very different.

Besides, we already have PRT. It's even more widespread than you suggest.














































It's called the "automobile". The pathways are called "roads", which are made with a material called "asphalt". They are powered by a liquid, petroleum-derived and flammable fuel called "gasoline" in North America and "petrol" in Britain and Australia. The wider pathways are called "expressways", and many nations have entire networks of those pathways. The United States calls it the "Interstate". Germany calls it the "Autobahn". Britain calls it the "Motorway". China is calling it "Gao Su Gong Lu".

Unfortunately, the chemical reaction that drives those capsules creates toxic fumes that are polluting the global environment, and urban areas in the United States have been especially wrecked by excessive dependence on PRT.

Now that the price of PRT fuel is skyrocketing worldwide, and the environmental effects of PRT fuel exhaust is becoming more known, many people are rethinking their relationship with PRT, and whether we should ditch our fixation with PRT in favour of modes of transport that are less intensive on energy; all those modes involve sharing the same room with strangers.
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Old June 13th, 2008, 12:12 PM   #50
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Besides, we already have PRT. It's even more widespread than you suggest.....It's called the "automobile".
Classic...and quite correct too!

What people are imagining is a futuristic version of what are, essentially, the same cars that we have today....

Just throw "cars" and "car-sharing" and "car-pool" together and add
"computer-guided" into the mix, add a drop of imagination and stir...

and voila, PRT!



Cheers, m
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Old June 13th, 2008, 01:24 PM   #51
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!?!?!?!

I'm not talking about the Washington Metro, I'm talking about your comparison of PRT costs for elevated and at-grade, not including right of way, to light rail costs for tunneled, elevated and at-grade, including right of way and adjacent utility and roadway reconstruction.

You already know that Link was voted down the year before as a heavy rail metro. I've told you this several times, and you still just can't accept it.

You're incredibly dishonest in every conversation we've had about transit and transportation. You feign confusion and deliberately pretend I've said things I haven't in order to appear right. The crazy thing is that you really do seem to think you're being rational.

Frankly, I think people like you are part of the reason we have such a hard time getting transit built. Every person like you out there confuses dozens of others who don't have the time or energy to sort out your deception, so we end up with FUD killing projects right and left.

UrbanBen,

All I see in your posts is blind assertions that light rail must be cheaper than other alternatives. My response has been to offer real data showing the contrary. The numbers are quite compelling:

WVU PRT - $89 million per mile (Estimate in 2004 dollars from Light Rail Now)
Washington Metro Largo Town Center Extension - $147 million per mile
Seattle Central Link light rail initial segment - $176 million per mile

Your response is to complain that the data is imperfect, yet you never offer any data of your own. Your entire point of view seems to be based on defending Sound Transit in general and Central Link in particular. My own position is that no cause is best supported by blind allegiance. When a project is hopelessly over-priced, people should speak out.

Thank you for patiently tolerating my views,
Greg V.
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Old June 13th, 2008, 02:23 PM   #52
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Classic...and quite correct too!

What people are imagining is a futuristic version of what are, essentially, the same cars that we have today....

Just throw "cars" and "car-sharing" and "car-pool" together and add
"computer-guided" into the mix, add a drop of imagination and stir...

and voila, PRT!



Cheers, m
Yes, I agree PRT is a lot like the automobile. It is convenient, private, always available, and point-to-point, just like a car.

But then, PRT is very different from the automobile in many other ways:
- more cost effective than autos or other forms of transit.
- much safer than autos or other transit.
- much more accessible than other transit.
- quicker than autos or other transit.
- more energy efficient per passenger than autos or other transit
- less polluting than autos or other transit.
- infrastructure that is much more city-friendly than autos or any form of transit (freeways, anyone?)

So, if I read you correctly, you seem to object to PRT because it is too much like a car. But since the only things cars and PRT have in common are privacy, convenience and availability, I'm sure PRT designers can accomodate your needs by producing a less private, more inconvenient, and less availble PRT system that will meet your notion of what good transit should be!
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Old June 13th, 2008, 04:17 PM   #53
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PRT seems to be an interesting possibility for a feeder system to mass transit. But installing PRT citywide seems impossible to me. The problem is, that you have yet another transit system. And with the similarity to cars it will come to PRT jams in downtown.

I don't see PRT as a viable alternative to metro, light rail or bus systems just because of the room it needs. Take a bus. Rush hour scenario: 12 meters long and able to carry 50 - 70 people fully occupied. PRT: 3 meter long and 4 persons. 50 / 4 = 12 x 3 = 36 m. It just needs a awful lot of room.
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Old June 13th, 2008, 08:16 PM   #54
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PRT seems to be an interesting possibility for a feeder system to mass transit. But installing PRT citywide seems impossible to me. The problem is, that you have yet another transit system. And with the similarity to cars it will come to PRT jams in downtown.
PRT is susceptible to congestion just like any network. However, there are fundamental differences with the automobile that make it less of an issue for PRT:
- PRT benefits from intelligent, realtime routing. Once there is a mature PRT grid with many paths from A to B, the PRT automated routing system can easily route vehicles along the route with the least congestion. In effect, PRT routing algorithms can distribute the load more efficiently than any other system (auto or transit).

- PRT is on a segregated guideway and is therefore less susceptible to random congestion-triggering events like accidents, vehicle breakdowns, etc. Even if a PRT vehicle breaks down, which should be rare in a well maintained system given the checked redundant components, the routing system can immediately route around the bad guideway segment.

- PRT networks can easily expand as demand warrants it. If there is consistent congestion on a certain corridor, PRT guideway can be added one street over and linked in seamlessly to the rest of the network. This is more difficult to do with other modes because the infrastructure is much larger and more inflexible. It would be difficult to add a freeway lane or rail line one block over from a congested area, but you could do it with a flexible, lightweight infrastructure like PRT.

If density on a PRT network ever became a real problem they could do what other dense cities do - go underground. That may seem silly, but Masdar City is doing it. In the long term, if PRT catches on, it would be a viable vector for expansion.

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I don't see PRT as a viable alternative to metro, light rail or bus systems just because of the room it needs. Take a bus. Rush hour scenario: 12 meters long and able to carry 50 - 70 people fully occupied. PRT: 3 meter long and 4 persons. 50 / 4 = 12 x 3 = 36 m. It just needs a awful lot of room.
Yes, from a pure numbers perspective, PRT consumes more space per passenger than buses during the rush periods. But, all space is not created equal, and the space PRT uses is away from the street level. If you look solely at street level impact, PRT is about as space-efficient as you can get.

If the concern is passenger density, then PRT is on par with streetcar/bus systems. Consider a 70 passenger bus running at 3 minute intervals (aggressive given city street congestion). That's a passenger every 2.5 seconds. PRT running at 2 seconds headway has a realistic capacity of about 1400 vehicles per hour; at 1.1 passengers per vehicle, that's a passenger every 2.33 seconds, and the PRT vehicles have no impact on other street level traffic. The same comparisons can be made to street level rail.

These comparisons don't generally apply to metro rail systems, which have 8-car trains capable of moving 40k passengers per hour. I envision PRT complementing such trains, not replacing them. For example, PRT would work well in big city neighborhoods that are poorly served by the metro systems, as circulators.

But for medium to medium-high applications that are currently served by light rail and buses, PRT compares quite well (especially with fossil fuel prices pushing bus operating costs up).

BTW, Wonwiin it's nice to see reasoned opposition for a change. There is certainly room for reasonable debate on PRT, but "here come the crazies" is a point that is very difficult to respond to rationally.
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Old June 13th, 2008, 09:19 PM   #55
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Underground?

This is a rendering of one of the 3 station in the heathrow Airport...it will be placed in the building.
I think it will be a wonderful solution to use this type of station underground in some part of city were the viaduct could be really an element of disturbing.
The money could be saved with a cut and cover system thanks to the small proportion of the system...

image hosted on flickr

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Old June 13th, 2008, 09:27 PM   #56
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I'm a full-time employee for ATS, makers of the ULTra Heathrow PRT system. I would agree that building a reliable control system is a significant effort. PRT vendors do have to plan for control system failures. We have to make a strong argument that our solutions will work, or else we would not be able to obtain insurance or regulatory safety approvals. Our solutions take a number of approaches, including redundant design.

Elevated guideway cost is a function of vehicle weight squared. Our vehicles are lightweight, so our guideway is inexpensive. I am using actual Heathrow costs to make this claim - I am not using cost estimates.

Station capacity per berth is high. Be sure to see the ULTra diagonal berth operation in the youtube video in the first thread post. Diagonal berths increase capacity. A two-berth PRT station can serve 300 vehicles per hour, a twelve-berth PRT station can serve 1,300 vehicles per hour

It's a bit difficult to generalize about transit project funding. PRT enjoys a very high level-of-service, so is competitive with private auto travel. For Heathrow, BAA considered all transit technologies and chose PRT. For Masdar City, all transit technologies were considered and both PRT and mass transit won - other parts of Dubai have LRT.

At the last Calthorpe-led public meeting I attended a few months back, Calthorpe advocated 10 story buildings in a two-story area. Even his oldest projects produce more density compared to adjacent areas. I think you should take a second look at Calthorpe.

Masdar City PRT is an urban application connecting to mass transit. I prefer the use of PRT as a complement to other forms of transit. There's plenty of market out there for all transit modes. PRT is going to follow an "adoption curve" just like other new technologies. Politicians don't choose new technologies for various good reasons, but new technologies still get adopted. In 1888, the electric trolley was a very risky idea. By 1905, it was the dominant mode of transit.
Since you're an expert in the field, how about a link to the ATS website, and a little more quantification of the assertions made above? I'm sure your CEO will back you up.
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Old June 13th, 2008, 11:43 PM   #57
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No one is seriously suggesting building BRT anywhere anymore.
That would be why 100 systems have sprung up in various cities over the last few years, and several are under construction right now. No one here is suggesting building light rail anymore, they're getting the same or better performance for a fraction of the price. Better still all they have to do is build the system, and they can subcontract out routes as they need them without special equipment required.

Quote:
There is no question that these projects will be built. The major question is the degree to which they will be true Bus Rapid Transit. There is a tendency for BRT projects to lose key features such as off-vehicle fare payment, traffic signal priority, and restricted access travel lanes.
If they don't have traffic signal priority and exclusive travel lanes for the entire route it's not BRT. It's a Bus. There's a huge difference. You also need things like the ability for buses to leave the BRT system (where they do become just a Bus but it's still an advantage over other systems), and the ability for Buses to pass each other at stations - for express routes to be able to operate at the same time as core routes. There have been way too many systems in the USA tagged as BRT that are quite simply not BRT. Everywhere they have been put in they have worked exceedingly well (to the point many plans for light rail have been totally scrapped). They still require some money spent on them, it's alot less than light rail, but it's not just a matter of painting a few lines, you need stations, ticketing, priority where required (and ideally very few places where you don't have your own ROW). That's going to cost money, if spend peanuts you won't get anything.

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Originally Posted by TransportEnthusiast View Post
So, if I read you correctly, you seem to object to PRT because it is too much like a car. But since the only things cars and PRT have in common are privacy, convenience and availability.
It's not going to work as a competitor to cars without using almost as much surface area as cars do, which is already heaps. It's only going to work in places were people don't have cars (airports, educational campuses etc). Effectively duplicating the entire road system in order to gain that level of convenience (still without enough ease to carry cargo door to door etc, is quite simply insane in this day and age. If it's going to work anywhere remotely it will work somewhere like Masdar that doesn't have cars for it to compete with.
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Old June 13th, 2008, 11:54 PM   #58
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- PRT benefits from intelligent, realtime routing. Once there is a mature PRT grid with many paths from A to B, the PRT automated routing system can easily route vehicles along the route with the least congestion. In effect, PRT routing algorithms can distribute the load more efficiently than any other system (auto or transit).
Automated routing systems are not exclusive to PRT. There are test runs with driverless metros and some are existing (Paris). You can automate almost every transport system.

Quote:
- PRT is on a segregated guideway and is therefore less susceptible to random congestion-triggering events like accidents, vehicle breakdowns, etc. Even if a PRT vehicle breaks down, which should be rare in a well maintained system given the checked redundant components, the routing system can immediately route around the bad guideway segment.
For me a segregated guideway is actually not really positive. It is easy to install in a new city but given that most cities are quite old and dense you have to install yet another system. Light rail has the flexibility to be able to use the same streets as cars in the city center and use seperated tracks in the outskirts.

Also to make a grade seperated PRT effective you actually have to copy most of the street map of the city with the new guideways and this will get expensive. Without that rerouting won't be easy.

Vehicle breakdowns will occure more often than in a metro, light rail or bus system because of the higher number of vehicles needed alone to operate PRTs.



Quote:
- PRT networks can easily expand as demand warrants it. If there is consistent congestion on a certain corridor, PRT guideway can be added one street over and linked in seamlessly to the rest of the network. This is more difficult to do with other modes because the infrastructure is much larger and more inflexible. It would be difficult to add a freeway lane or rail line one block over from a congested area, but you could do it with a flexible, lightweight infrastructure like PRT.
The easiest way is actually the bus. Nothing beats the bus in flexibility in operations.


Quote:
Yes, from a pure numbers perspective, PRT consumes more space per passenger than buses during the rush periods. But, all space is not created equal, and the space PRT uses is away from the street level. If you look solely at street level impact, PRT is about as space-efficient as you can get.
As already said grade seperation means to find new space to occupy and that has to be difficult and expensive.


Quote:
These comparisons don't generally apply to metro rail systems, which have 8-car trains capable of moving 40k passengers per hour. I envision PRT complementing such trains, not replacing them. For example, PRT would work well in big city neighborhoods that are poorly served by the metro systems, as circulators.
Yes, it could be a perfect feeder system for low density suburbs.


Quote:
BTW, Wonwiin it's nice to see reasoned opposition for a change. There is certainly room for reasonable debate on PRT, but "here come the crazies" is a point that is very difficult to respond to rationally.
You are welcome. Just to say I do like Monorails, PRTs, etc. But to replace established systems PRT and especially Monorail are missing the revolutionary new way of doing things. Why would I invest in a system I have to built a totally new infrastructure for doing more or less the same as my already established public transport systems?

I used several european metro systems on a daily basis and I just can't see PRTs in city centers. Metro, light rail and buses just serve most cities well. I personally prefer to ride the tram even if there is an alternative metro route .

Another point against PRT is, that it not only competes against mass transit but also even more against the car. And it is really difficult to compete against it. The car is, as already said, the ultimate PRT.
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Old June 14th, 2008, 12:00 AM   #59
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Well I'm glad to read that last paragraph, Shado. (Post #57)

A salient point here would be: how many nodes are expected in these systems (and what's the total track length). From the postings above, Brisbane Australia seems to be a good example to start with, although I am sure there are many more. Any decent model would do!
  • From where to where will you actually be able to travel?
  • At how many points will you be able to get on or off the system?
  • What is the anticipated traffic flow, and how does it break down over a weekday?
  • How much will it cost?


Lots of experts have previously posted ...
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Old June 14th, 2008, 12:17 AM   #60
Shado
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Join Date: Apr 2003
Location: Brisbane, Australia
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Having seen quite a few computer systems that deal with routing, they become incredibly complex as you increase the number of nodes and items using them. I've seen people write systems with just a couple (in this case they were simply automated forklifts) and no matter how hard they tried, the system was still more efficient with a single forklift than it was trying to have the two avoid each other. (They would spend more time getting out of each others way than doing what they were supposed to).

Obviously the best way for people to determine if PRT works, and in what situations it works in is to build it and see what happens. We can talk theory all we want, but eventually it becomes a circular argument. If someone builds it and it's cost effective and works, it will be repeated until someone puts it in a situation that exceeds what it's capable of and then we know the boundries. If someone builds it and there are problems, it all gets put on the shelf until someone claims to solve them.
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