PRT Could Be Future of Travel (Market Forecast by Paul Justus)

If you are old enough or have watched enough TV re-runs, you may recall the animated cartoon, “The Jetsons,” which presented a different transportation vision of the future.

In “The Jetsons,” people traveled in long lines of space-age cars that, somehow, flew through the air in their daily commute.

If advocates of a developing technology, known as Personal Rapid Transit (PRT), have their way, in the not-too-distant future, people should have the option of traveling in such a car. However, with the PRT, instead of flying through the air, the small pod-like cars would be traveling along an ultra-light monorail system.

Beginning in the 1960s, engineers began working on the research and development of various PRT concepts.

More recently, a 2003 study by the Advanced Transit Association, a policy organization that endorses PRT research, reported that at least 14 engineering groups throughout the world have been working on the development of PRT systems. The most advanced PRT projects include a proposed 2.6-mile line at London’s Heathrow Airport and a shorter stretch at the Dubai International Financial Center. PRT developers expect to construct and test the Dubai PRT within two years. In Minneapolis, the company, Taxi 2000, constructed a PRT prototype that runs 60 feet.

Proposed PRT systems would be very different from conventional forms of mass transit. According to a description by the Austin Citizens for PRT, “PRT is a system of (generally) elevated one-way guideways connecting small stations spaced relatively close together, with the stations placed off of the main guideway to allow vehicles to by-pass the stations.

“Small, automated, three-person vehicles carry individuals or friends along the guideway at 25 to 50 mph non-stop from any station on the system to any other station in the system.

“Since the guideways are elevated, PRT operations will not interfere with street-level traffic or require reductions in road lanes or parking. The only street-level space required for the guideway is room to put a two-foot diameter support pole about every 60 feet. Stations are very small, with typical stations being only 30 to 50 feet long versus 200-plus feet for light-rail stations.”

PRT proponents present a long list of benefits and advantages over current systems of mass transit. Generally these benefits fall into the categories of convenience, land use, cost and safety. The list of benefits includes:

Convenience

Increased ridership due to PRT cabs ready and waiting.

Greater privacy for an individual to travel alone or in a small group.

Reduced travel time with no stop-and-go travel.

Small design would allow PRT stations in buildings and shopping malls.

Environmental Benefits

Less energy consumption due to lighter weight, fewer stops and starts, high efficiency of electric motors, and partial recovery of energy during braking. PRT is independent of fossil fuels.

Low visual impacts: Compared to other transit options, PRT guideways allow greater flexibility. PRT guideways can be run through alleyways, in existing road medians, or behind existing tree lines and buildings. The guideway covers can be painted to match the needs of the neighborhood.

Reduced roadway and parking needs. Roadways and parking pavement covers about 50 percent of modern cities. The Taxi 2000 Skyweb PRT requires two-foot diameter support columns every 60 feet or so. Less need for pavement, potentially, would help prevent stormwater runoff and protect water resources.

Smaller stations and guideway supports reduce conflicts with existing infrastructure including underground utilities (water, sewer, storm drains, gas, electric, cable TV, telephone, fiber optic cables), trees, private property rights, sidewalks, etc.

Small stations located in a network every half mile would encourage transit-oriented development throughout a city.

No tail pipe emissions.

Inexpensive

Reduced labor and operating costs due to automated fare collection and automated guidance.

Reduced station size resulting from smaller vehicles, high station vehicle throughput and real-time system allocation of vehicles. This again acts to reduce station costs and visual impact.

The ability to be implemented in an incremental manner; beginning as a single loop, the network could evolve into a comprehensive system as demand warrants.

Ability to use existing easements, which would reduce the need to purchase right-of-way from property owners and greatly reduce start-up costs.

Lightweight vehicles and track reduces the capital cost while the absence of drivers and instant service reduces the operating costs per passenger mile. Depending on the design, cost estimates generally range between $5 million and $15 million per mile for a PRT system.

Increased Safety

Elevated PRT guideways eliminates the possibility of collisions with automobiles, pedestrians, children or pets.

Dispersed nature of PRT makes it a less likely terrorist target.

Even with such a long list of asserted benefits, numerous critics argue against PRT systems. Critics often site failed development attempts in the past, visual impact, the high cost of existing “Group Rapid Transit” systems, and question the projected capacity of PRT systems.

One noted critic, Randal O’Toole of the Thoreau Institute, argues it would be much cheaper to imbed Intelligent Transportation System (ITS) technologies in existing highways that would take over the speed and steering of automobiles. Such a proposal, like the PRT, would increase capacity and reduce, or eliminate, crashes.

Given the ongoing development of PRTs, can Northwest Arkansas residents expect to be scooting around on ultra-light monorails anytime soon?

Until PRT promoters present a fully developed technology, it is difficult to justify making immediate or extensive plans for such systems.

However, given rising gasoline costs, increased air pollution, and increasing automobile congestion, it would be sensible to keep an eye on all potential transportation solutions and to include them in any kind of alternative transportation analysis.

(Paul Justus is a regional planner with the Northwest Arkansas Regional Planning Commission.)