How Personal Rapid Transport Works


Announcer: Welcome to Stuff You Should Know from HowStuffWorks.com.

Josh Clark: Hi, and welcome to the podcast. I'm Josh Clark, a staff writer here at HowStuffWorks.com. With me is the writer's editor extraordinaire Mr. Chris Pollette. How's it going, Chris?

Chris Pollette: It's going great, Josh. Thanks for asking.

Josh Clark: So, Chris, I notice you shaved your goatee. It's startlingly different.

Chris Pollette: Yeah, yeah. I'm not used to the air conditioning on my chin, but I'll get used to it.

Josh Clark: Well, we're not used to it around the office. We're actually lamenting the loss of it. We're sitting shiva over Chris's goatee. We've got the mirrors covered, but we have to soldier on, don't we, Chris?

Chris Pollette: Oy.

Josh Clark: Yeah. So I'm thinking we could soldier on by talking about whether or not there's going to be a new kind of taxicab in the future. What do you know about this?

Chris Pollette: Well, I do know that gas prices are going up, and people are looking at all kinds of alternatives, even something that might seem like it's right out of one of those 1940s, 1950s art deco, "This is the wave of the future" sort of thing.

Josh Clark: Sure, like Tomorrowland at Disney World, right?

Chris Pollette: Tomorrowland, yeah, the WEDway People Mover.

Josh Clark: Yes.

Chris Pollette: Yeah, yeah.

Josh Clark: So what we're talking about is personal rapid transit or PRT, and it's actually not a new idea. It does find its roots in the '50s. An American urban designer started toying with the idea. What it does is it takes the best of both worlds of subways and taxis and puts them together. It's personal rapid transit because there's so many cars on this rail line that you don't have to share with anybody, so people who are unsettled by the homeless or are xenophobic to a clinical degree can rest easy on this ride. And it also takes you pretty much exactly where you wanna go. Surprisingly, it's less to build than light rail by a long shot. They're doing one at Heathrow Airport in the infamous Terminal 5, and it costs about $16 million for a mile track, total cost. Most light rail cost about $40 million, which is amazing that it's got it beat by that. Why don't we have this installed everywhere now?

Chris Pollette: Well, I would guess that, even though they are claiming that it is less expensive than light rail, that there's just so much more infrastructure involved in building a light rail system. You know, from what I've read in researching for the podcast, the cars we're talking about here for these PRT systems are small. They're like a personal automobile rather than a big honking train, which I'm sure costs a lot to build. Plus the track would probably need to be considerably wider for a light rail train. So, you know, it sort of makes sense that it would be a little bit more cost efficient, even with the number of stops going up.

Josh Clark: But even with hard numbers, there's a lot of people who aren't swayed. Personal rapid transit systems have found vocal opponents everywhere that they've been proposed. You watch "The Simpsons," right?

Chris Pollette: Oh, yeah.

Josh Clark: Okay. You've seen the monorail episode?

Chris Pollette: It's one of my favorites.

Josh Clark: It is a great episode. It has it all. It has Leonard Nimoy, the Opossums. It's a spoof of "The Music Man." But really, when I was researching personal rapid transit, I realized that the monorail episode of "The Simpsons" is a subtle indictment of PRT systems. And while, in the episode, Homer Simpson is the conductor of the monorail, what better metaphor for a failing computer system than Homer himself, right?

Chris Pollette: That's true, yeah. And that's one of the big criticisms of the PRT system -

Josh Clark: Yeah, it is.

Chris Pollette: - is what happens if one of the cars fails? If you're on the same track as everyone else, and especially if they're moving in as close proximity as it suggests that we will be if we use these systems, it will be essentially bumper to bumper.

Josh Clark: And they are unmanned. They are computerized. They're computer-driven, which is good because they can run 24 hours a day, but if they're unmanned, then what happens when they stop? Like you said, you've got all the cars behind you stopped behind you. It could be just like a complete nightmare. It's like being stuck on a roller coaster, but you're not at an amusement park. You're trying to get home or get to work.

Chris Pollette: Maybe they'll install horns in them, so at least we can, you know, have the satisfaction of honking at the other cars.

Josh Clark: Right, yeah. That'd be awesome actually.

Chris Pollette: But I was intrigued that they're being installed in some places, I think Sweden and Abu Dhabi, which is sort of ironic, considering they would have gotten the money for that from oil.

Josh Clark: Yeah, yeah, that is ironic, but they are starting to - they're actually - the United Arab Emirates and Dubai and some of these other areas are really starting to lead the charge on going green. And the city called Masdar City - it's a development outside of Abu Dhabi - they're aiming to become the first zero-carbon-footprint city ever, and part of that is the personal rapid transit system they're implementing. And this is not a test. I mean, they're putting in a whole 1500-stop system. So it's a huge deal, and there's going to be a lot of eyes on Abu Dhabi to find out, you know, if this can really work, and if it will fail like people expect, or if it could be the wave of the future for taxis.

Chris Pollette: That's fascinating.

Josh Clark: Agreed.

Chris Pollette: It'll be exciting to see, you know, that this may be a real solution.

Josh Clark: Yeah, I hope so because we're drowning here. If you want to learn more about personal rapid transit, read, "Will There Be a New Kind of Taxicab?" on HowStuffWorks.com.

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