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Response to jollyreaper2112 (Original post)

Wed Feb 13, 2013, 09:16 PM

14. PRT, Personal Rapid Transit, a Solution is search of a problem to solve.


The problem with PRT is simple, how do you a LARGE number of people on one better then a Light Rail Vehicle (or even a bus) OR provide more service then simply walking?

Transit throughout the world fall into several overlapping categories:

1. Heavy Rail, multi car movement permitted the movement of hundreds of people at once.

2. Light Rail (the name Light Rail was invented in the 1960s due to American/Canadian English using the term Streetcar for what the rest of the English Speaking world calls a "Tram" is designed for areas where 50-100 people at a time constantly. Many LRVs run empty as they return to pick up more passengers but the purpose is to pick people up and move them down the track. Please note some cities have Bus rapid transit, bus lanes instead of rails, but used the same as an LRV, to move large number of people up or down the bus lane. Such Bus Rapid Transit are more like LRVs then the buses mentioned below, but by NOT being tied in with a rigid rail system able to exit the bus lane, but at the cost of moving less passengers slower (and it is due to the fact LRVs can move more people faster then a bus lane is why LRVs are making a comeback over the last 40 years).

3. Buses. Ideally where you have 25-50 passengers and thus can NOT justify a separate transportation line. Today, often used in areas where LRVs should be operating (and then the LRVs should be on its own line) but in areas where an LRV can NOT be justified in many ways ideal, more flexibility but at slower speeds (and the slower speeds is not only tied in with being mixed with automotive traffic, but that many LRVs have they own right of way and thus do NOT have to pick up passengers and then wait for a light to change, a problem many buses suffer from. Please note, many of the old Streetcars systems in the US were more like modern bus lines then LRVs in that they did NOT have their own right of way.

4. Automobiles. Yes, Automobiles MUST be considered when discussing mass transit, for it is the first options for many when they is no other option. The problem is parking the car, both at home, when shopping or working. On the other hand, able to go anywhere where a paved road exists. Automobiles are the first choice in Rural Area (and was the prime area of Automobile growth in the 1920s).

5. Walking. Slow, but sure, can go anywhere any other means of transportation can go (except maybe planes and boats). People can walk three miles an hour, thus one mile in 20 minutes. Yes, a lot of people today, take their car instead of walking a mile, but walking is NOT that much out of the running for such short trips (and if you tie in bicycles you are into a 3-10 mile maximum range).

Where does a PRT fit into the above? Technically it should replace the automobile, saving the needs for parking spaces, but then you lose the ability to drive it right to your home, even if your home is in the middle of no where. In heavier populated areas, buses, then LRVs, then Trains (And finally just walking) became better options. Thus park and rides are very popular for people living in areas that can NOT support buses, LRVs or Trains just by the people around the stops for buses, LRVs or trains.

In a PRT you are stuck with what ever track your PRT is on, like a Bus, LRV or train, but unlike an Automobile. PRT also can not handle the volume of people a bus can, let alone an LRV or a Train. Everything a PRT can do, something else can do better, and that is the main problem with the whole concept, it is an attempt to provide an automobile on a track system like a LRV and you end up with something that is NOT as flexible as an Automobile, nor can handle the mass of people a bus or LRV can handle.

PRT is a solution looking for a problem, the problem of people living in low density communities wanting a high tech transit system, rather then a bus or an automobile, when the later two are just a better fit for such low density areas.

PRT can NOT solve the problem of people wanting to get away from crowded urban centers for PRTs can NOT handle that level of population (again buses can do it better, through LRVs and Trains do it even better). PRT can not solve the problem of access to mass transit for low population areas, better the a bus or the Automobile. The PRT can not even address the problem of people moving from low population areas to high density population areas, better then driving your car (or walking or riding your bicycle) to a LRV, bus or Train stop and taking such Bus, LRV or Train to and from the high population density area (i.e. where people work and shop). PRT is a solution looking for a problem to solve.

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jollyreaper2112 Feb 2013 OP
Lydia Leftcoast Feb 2013 #1
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LineNew Reply PRT, Personal Rapid Transit, a Solution is search of a problem to solve.
happyslug Feb 2013 #14
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happyslug Feb 2013 #16
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