FAQ

What are the advantages of PRT compared to tram and bus?

PRT offers you a private vehicle which takes you directly to your destination. The big advantage compared to tram and bus is thus the improved travel time and comfort. Read more about this under Comparisons.

What are the advantages of PRT compared to the car?

Maybe the greatest advantage compared to the car is that the PRT vehicles run on electricity directly off the grid. There are also other advantages such as reduced congestion and accidents and removed parking problems. Read more about this under Comparisons.

Why are Beamways guideways double direction instead of single direction?

At Beamways we have come to the conclusion that double direction lines have many advantages. And in fact they are not more expensive than single direction lines when creating a system of a certain quality. Read more about this under Comparisons.

Does every intersection have to be a roundabout in a double direction system?

Intersections in a double direction PRT system do get more complex than those of a single direction system. One way of building such an intersection is using a roundabout. The main advantage of a roundabout is that it is all in one plane. The drawbacks are that capacity is limited and that the radius of the curves often needs to be tight which results in low speed traversing the intersection.

Depending on the capacity- and speed requirements as well as the available space you can select to build different kinds of two layer intersections instead of roundabouts. There are plenty of examples on these designs in our regular road network.

The Beamways system allows very tight curve radius and steep slopes which simplify the design of roundabouts as well as dual-layer intersections where space is limited.

Why is the company called Beamways?

The word beamways is constructed from beam and way. We think that these words capture the essence of PRT quite well. As beam can also mean ray of light we get an extra glare to the company! Of course the availability of beamways.com also played a role in the selection of the name…

Doesn’t small vehicles result in small capacity?

The capacity of a mode of transportation depends on the size of the vehicles and the headway between vehicles. In this respect PRT works like cars on a road; small vehicles with short headways. Train and tram instead have large vehicles and long headways. For instance the newly built tram line in Stockholm, Tvärbanan, has a headway of 7,5 minutes in the rush hour. As each tram can carry a maximum of 400 passengers the total capacity is 3200 persons per hour. A PRT line with two second headway and two persons per vehicle has a capacity of 3600 persons per hour. In contrast with the tram where most people must stand in the rush hour the PRT vehicles offer seats for everyone.

Thus a PRT line has about the same available capacity as a tram line. But thanks to the different traffic model of the PRT system the capacity requirement is drastically lower. A transit system relies on the spoked wheel principle in that wherever you want to go you have to first travel to a hub where you can change to another line to take you to the final destination. This results in aconstructed traffic flow increase close to the transit hub which is not consistent with where people really want to go. A PRT vehicle chooses the shortest path to the destination which most often does not pass the city center. This results in a much more evenly spread out traffic flow and a reduced mean trip length which means that the PRT system can perform more traffic work at a certain line capacity.

Is there a difference between PRT and Podcar?

The acronym PRT has been prevailing for a long time. Now that this type of system is about to become commonplace this name was thought to be too cryptic and technical by IST (Institute for Sustainable Transportation) in Stockholm whcih coined the flashier term Podcar. This term is said to include dual-mode apart from regular PRT. Dual-mode allows vehicles to leave the guideway and drive on a regular road the last part of the trip.

Why is the Beamways system suspended?

There are many advantages and drawbacks with a suspended PRT system compared to a supported one. Out of the many systems that have been proposed over the years slightly less than half have been suspended and slightly more have been supported. Notably one system used both types of vehicles!

Some of the more important differences between suspended and supported systems are listed below.

  • Supported systems have the beams closer to ground level. This has the advantage of slightly cheaper posts and ground works. A drawback is that the beams obstruct a larger part of the sky as seen from below.
  • It is easier to design a switch for a supported system. The problem of switching a suspended system has however been solved by Beamways and numerous other systems.
  • In a suspended system the beams must be held out from the poles by a horizontal member. But for double direction systems like Beamways you would have to have this anyway.
  • Suspended systems have a slot in the downward facing surface of the beam while supported systems have a slot in the upper surface. This gives suspended systems an inherent advantage when it comes to weather protection, particularly against snow.
  • Supported systems with at grade sections are prone to people and animals entering the guideway and possibly climbing up to elevated sections where they run a risk of being hit by a vehicle while having nowhere to escape. Suspended systems have the beam at a level of approximately 2 m even at a ground level station.
  • Suspended systems can hide power rails inside the guideway beam so that it is out of reach even for trespassers.
  • Suspended systems can have solar panels on top of the guideway and thereby produce its own electricity. A width of 1-2 m allows for a Beamways system to be net zero energy in many parts of the world.
  • Supported systems are susceptible to debris such as tree branches falling on the guideway to a much higher extent than suspended systems.