Ten Things PRT Does Better

This discussion item comes from being asked "What can a PRT system do that a tradition large vehicle system cannot, given adequate funding of the traditional system?" So here is a (incomplete) list of 10 things a PRT system can do that a bus or train system can't - even if we posit that the bus system has the funding necessary to push headways down to be competitive with the PRT system.

Chris

1. Eliminate transfers. - Traditional transit systems are a series of loosely-coupled line-haul routes, resulting in most trips requiring a transfer and the associated de-boarding and waiting for the next bus or train. A PRT system allows non-stop travel from any station in the system to any other station in the system. It's actually part of the common definition of PRT. So if you build a series of PRT corridors connected to a downtown circulator PRT, there is no need to take one vehicle into downtown, and then transfer to a downtown circulator or to another route to get to a destination on another corridor.

2. Guarantee a seat to all riders. The PRT system is designed so that all riders are seated. Urban rail systems usually provide seats for about a third of the vehicle's capacity. Bus systems can also require people to either wait for the next, possibly full, bus or to strap-hang.

3. Match PRT's high average speed. Urban bus systems average around 15 mph (per APTA) by the time you include stops and traffic. Light rail systems come in around 21 mph. Taxi 2000 is planning for the first installations of Skyweb Express to run at 40 mph (perhaps a bit higher) in the suburban area and 25 mph while in the downtown core. If a typical commute is 60% suburb and 40% downtown, average speed should be about 35 mph - over twice the bus speed and 50%+ faster than the rail system.

4. Allow 100% of the system capacity to be used by wheelchairs or bikes. Standard transit practice is to provide space for two wheelchairs per bus and the bike racks I have seen are similarly sized for two bikes at a time. What happens when there is one wheelchair or bike on the bus and two wheelchair-bound or cycling friends want to get on at the next stop? Sure, it's rare but it does happen. With the PRT system, every vehicle can be used to carry a wheelchair equipped patron, plus a walking attendant OR a person and their bicycle. The system essentially provides a constant stream of usable capacity at every station to carry however many wheelchairs or bikes show up.

5. Eliminate running to catch (or miss) your ride. Being 30 seconds late to a mass transit and missing your ride is a bit of a problem - you have gone from being 30 seconds late into the door at work to 10 minutes late - or whatever the headway is for the system. In a PRT system, you are simply 30 seconds behind where you would normally be.

6. Eliminate the need for a route map as well as a schedule. Since every PRT vehicle goes to every PRT station, there is no need to figure out which bus route you need to catch, watch for the correct bus on a street served by multiple routes, or even figure out which direction you need to be going on the system. All you need is the station code for your destination. The PRT system handles getting you from here to there.

7. Eliminate the possibility of missing your stop due to sleep, inattentiveness, or not being familiar with the area. Your stop is the only stop on your PRT trip. When the vehicle pulls into the station you are at your destination. If you happen to fall asleep on the way, the system will wait for you to press the door button for a time, say 30 seconds, then notify the system operator that there may be a problem. Having them shout over the intercom to wake is normally preferable to riding the bus or train to the end of the line.

8. Allow you to reject a vehicle that is dirty or in disrepair. If some gets sick in a bus, what choices do the other riders have? In this case, I will grant that having funding enough for 10 minute headways reduces the penalty for getting off of the bus and waiting for the next one, but you still have to either live with it or sacrifice your time. With PRT, you have the chance to inspect your entire car before boarding, and tell the system to send the offending vehicle to the maintenance depot. You then board the next vehicle, which should be there in the next minute or so.

9. Remove the possibility of being in an auto accident. While bus and rail are very safe (for the rider) in the event of a collision, what about the effect on your schedule and the trauma aspects of being involved in a collision? Full grade separation allows PRT riders to avoid the risks taken by systems that mix with traffic, however small it may be.

10. Eliminate waiting for the vehicle late at night. PRT provides the lowest wait time precisely when people are most sensitive to them - at evening and night when the system has spare vehicle capacity and can keep vehicles waiting in the stations for the next rider.