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Hyperloop: Pipes of Fancy

economist.com

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Re: Hyperloop: Pipes of Fancy

#91

Post by TimSchumann »

GuB-42 wrote: post #45

Can someone explain me how Hyperloop is supposed to work? There are so many things wrong with it. - Hyperloop is a vactrain, a century old idea, and to this day, despite numerous attempts, nothing came close to a working prototype, let alone something production-ready. - By contrast, high-speed trains carries millions of passengers every day in many parts of the world. They are safe, comfortable, and commercially via…

> So for me it just a daring publicity stunt (a borderline scam IMHO), something that Elon Musk is also known to be good at.

Agree with you on this point.

Sometimes I feel like I’m taking crazy pills when I talk with friends about Hyperloop. From an economic and engineering standpoint, it’s a complete non-starter.

Re: Hyperloop: Pipes of Fancy

#92

Post by godtoldmetodoit »

TylerE wrote: post #56
jengleton wrote: post #55

Earlier quoted context omitted.

You might not want to pop the emergency hatch when you're surrounded by vacuum.

Hatch in the tube, not the car.

The tube is vacuum, you'd need an airlock not just a simple hatch, no? How do passengers get from car to airlock without a suit?

Re: Hyperloop: Pipes of Fancy

#93

Post by thephyber »

chrisco255 wrote: post #37
TylerE wrote: post #30

Earlier quoted context omitted.

Say what? That’s crazy talk. Underground would be many times more expensive, and has much worse failure modes. What happens if the train loses power?

It's not crazy talk. The truth is they likely belong both above ground and below ground, depending on urban density or geography. And tunnels tend to have escape ladders every so many feet.

Elevated train platforms may have escape ladders, but I thought the Hyperloop tube was depressurized and the car within it needs to be pressurized. This poses a problem for the escaping passengers before they reach the ladder.

Re: Hyperloop: Pipes of Fancy

#94

Post by jcranmer »

vwat wrote: post #87
brunoqc wrote: post #3

https://youtu.be/2h6Cz4hwuEI How legit is that video and YouTuber?

It’s not legit at all. I’ve always been a fan, and all his busted videos in the past featured one very important feature: the violation of thermodynamics. He always showed why a product was physically impossible. But he doesn’t do that with a hyperloop. And ultimately, if you see through the repetition and downright nastiness, you see that his argument is essentially “hyperloop is very expensive, it would be unsafe a…

The problem with criticizing hyperloop on technical grounds is that there often isn't even enough substance to really criticize. There are several designs, which only really have "you put it a vehicle in a vacuum tube and go zoom!" in common--and even then, there's contention about vacuum.

So the only way you can really criticize it is on gadgetbahn grounds: it's shiny new technology [1], that's safer, cheaper, faster, better, stronger, etc. than the stodgy old infrastructure plans. It'll come in sooner and cheaper than them, we just need a few years [2] to finish designing them, and a couple million dollars [3] as well.

And if you've read all of my footnotes, you'll realize why this pitch is too good to be true. I'm personally not bothered by that so much as I'm bothered by the argument to stop investing in infrastructure because gadgetbahn is the future.

[1] Except "put trains in a vacuum tube" is a really old concept. But hyperloop is something "new," and the differences from vactrains is, uh, see above about the difficulty of pinning down any technical details.

[2] Looking to be 2 decades from "initial" concept to first implementation at this point.

[3] If you tot up all the grants so far, we're past $1 billion at this point to just study how to build this thing.

Re: Hyperloop: Pipes of Fancy

#95

Post by andbberger »

jcranmer wrote: post #89
andbberger wrote: post #84

Earlier quoted context omitted.

Waiting 10-30 minutes for a train isn't a technological consequence of rail transportation, it's a symptom of a catastrophically inept transit agency. What's stopping, say, Caltrain, from running trains at peak frequency all day? Incompetent leadership. They have the trains (which spend all day sitting idle _at_ terminus platforms), the have the crew (who also sit idle during the day), they have the capacity to run m…

> You might make the case that running more trains off-peak would increase maintenance costs. Alon Levy has done the math [1] and found that providing extra off-peak service is about 20% the cost of providing extra peak service, since the capital costs and labor costs dominate the actual operational costs. [1] https://pedestrianobservations.com/2018/01/22/base-train-ser...

Yup essentially getting all of that directly from Alon's various posts on Caltrain's incompetence.

Re: Hyperloop: Pipes of Fancy

#97

Post by anitil »

GuB-42 wrote: post #45

Can someone explain me how Hyperloop is supposed to work? There are so many things wrong with it. - Hyperloop is a vactrain, a century old idea, and to this day, despite numerous attempts, nothing came close to a working prototype, let alone something production-ready. - By contrast, high-speed trains carries millions of passengers every day in many parts of the world. They are safe, comfortable, and commercially via…

It's very irritating talking about whatever hyperloop is, because that the bar for what the hyperloop is keeps changing (Is it tunnels? Is it in a vacuum? If there's no vacuum isn't it just a tunnel? Is it your own car or a pod? There's solar panels somehow?).

If we wanted better transport we should invest in busses and trains, which have better carrying capacity and better failure modes than whatever hyperloop is supposed to have. Oh an over a hundred years of proven effectiveness.

But I think people want magic solutions to things rather than the simple, working solution that we already have.

Re: Hyperloop: Pipes of Fancy

#98

Post by jojobas »

AlexandrB wrote: post #9

This is evergreen when talking about Hyperloop: http://www.cat-bus.com/2017/12/gadgetbahn/ The problems with building this have nothing to do with technology but with right-of-way, investment, and politics. If those factors were solved, we'd already have high-speed rail in places where Hyperloop has been proposed. The fact that we don't says that Hyperloop is unlikely to be feasible as well.

Three words: vacuum expansion seals.

Re: Hyperloop: Pipes of Fancy

#99

Post by jcranmer »

alacombe wrote: post #75
nickik wrote: post #61

Earlier quoted context omitted.

> So for me it just a daring publicity stunt (a borderline scam IMHO), something that Elon Musk is also known to be good at. I think this is a very unfair and cynical way of looking at it. How it is a scam? He said, he thinks its a good idea and he released basically a little concept whitepaper on what his ideas are. He has never attempted to make any money from it, and he clearly just thinks its a good idea and that…

> He has never attempted to make any money from it, That's a blatant lie. https://www.engadget.com/2019-07-25-elon-musk-raises-120-mil... https://www.reuters.com/article/us-boring-company-fundraisin... .

That's raising money for Loop not hyperloop, as far as I can tell.
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