The closest thing to a large-scale, real-world PRT system is the project in Morgantown, WV. However, the vehicles are bigger than those in a PRT system: each one can carry about 20 people. During peak hours they run on a schedule, like a conventional transit system. That system, which was expensive and suffered from many problems, especially at first, may have helped give PRT systems a bad name, says Jerry Schneider, a professor emeritus of urban planning and civil engineering at the University of Washington in Seattle and a long-time advocate of PRTs. “People would get on the vehicles and they wouldn’t stop. It got ridiculed roundly in the press. At one point they talked about dynamiting it, tearing it down.”
After the initial problems, however, he says that the system has run well–it still transports students at the University of West Virginia. What’s more, he says that technology has improved since then–for example, small computers are now more powerful than the large mainframes used to control the Morgantown system. Several new PRT vehicles have been developed and tested on small tracks. But there haven’t been adequate demonstrations to convince local governments to approve the new designs and convince investors to take the risk. “The simulations run fine,” says Schneider, “But until you put people in the cars and run them out in the open air, you can’t really be sure what’s going to happen.”
While Heathrow and Masdar could provide the demonstrations necessary to convince other cities to adopt PRT, they are special cases with controlled environments, says Luca Guala, a transportation planner at Systematica, a company planning the layout of the PRT system at Masdar. In both cases, cars are banned, so there’s no competition. What’s more, at Masdar, the organization of buildings within the city has been modified to accommodate the system. Indeed, the city will be constructed so that the main level is several meters above the ground, primarily to make room for the PRT. It will be more challenging to incorporate PRT systems into existing cities. However, he says that the projects at Heathrow and Masdar will help drive down costs, and that could make them feasible elsewhere.