I've never been a huge fan of PRT, or personal rapid transit systems, which have been the future of transportation since Richard Nixon was president. On TreeHugger I once called the concept a cyberspace techno-dream, and the pro-pod people gave me an award for writing fish wrap. I never could figure out what it accomplished, other than placate people who think that everyone on a bus is either poor, deranged or both. Then I thought it was pretty much killed by the idea of the self-driving car. Why have a dedicated guideway when your podcar can go anywhere?

However a group in Raleigh, North Carolina, is working on a different kind of PRT. It was developed for the campus of North Carolina State University, where there is a long distance between libraries and a right-of-way that was planned for a monorail, another techno-dream. The ecoPRT is different from other systems I've written about; it's much lighter and narrower, holding two people sitting face-to-face. This means that the guideway can be much lighter too. It's shown as a lightweight steel truss rather than the usual concrete guideway. Eric Lamb, manager of transportation planning for the city of Raleigh notes:
Due to the small footprint of the vehicle (in-line seating) and low weight, there could be significant cost savings in building an elevated guideway when compared to other types of fixed guideway systems.
ecoprt comparison to car

EcoPRT compared to your standard SUV. (Photo: ecoPRT)

This makes a great deal of sense — a rail viaduct has to hold massive loads but it sits empty most of the time if a commuter train only goes over it every 10 minutes or so. The PRT system spreads the load over time and distance. The designers predict headway of as little as 1.5 seconds (I think they are dreaming on that point, but OK) meaning it can carry a lot of people, spread out over a lot of track. Their concept:

An ultra-light-weight transit system with autonomous vehicles that carry no more than two passengers at a time. The system will have dedicated roadways where the vehicles can be routed directly to their destination without stops. The advantages include 1) a target price of $1 million per mile of guideway infrastructure costs, 2) a transit system that is much quicker and less costly than either bus and light rail, and 3) a smaller overall footprint with less impact on the surrounding environment.
The designers see this as a serious alternative to the automobile, and if you read their page on the problems with automobiles, you will want to jump on board the PRT.
These significant problems are borne daily by everyone in America. It represents a tremendous cost to the nation. EcoPRT’s goal is to solve all of these problems by eliminating the expense and hassle of owning a car, significantly reducing the cost and space required for roadways and parking, and eliminating much of the environmental degradation that goes with America’s automotive culture.
EcoPRT on guideway zipping over town.

EcoPRT on guideway zipping over town. (Photo: ecoPRT)

There are still the basic problems that PRT has not solved — the last mile problem of getting to your home, the ugliness of the overhead guideways — although on that last point, these guideways are far more minimal. That’s why I thought the autonomous car would kill the idea; it can drive you home. By the way, there's also another vehicle that can take you home, works great at universities in temperate climates, and is even cheaper: it's called the bicycle.

However back in Raleigh, ecoPRT has made a smaller, lighter and cheaper pod car system that just might make sense. Now if they could somehow connect it to the light rail system being built in Durham, the Research Triangle might get a decent coordinated transportation system after all.

The author learned about ecoPRT as a guest of the Wake County Economic Development agency, on a visit to Raleigh and the Research Triangle area of North Carolina.

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Lloyd Alter ( @lloydalter ) writes about smart (and dumb) tech with a side of design and a dash of boomer angst.