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Hyperloop: Pipes of Fancy

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Re: Hyperloop: Pipes of Fancy

#131

Post by aaron695 »

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.

The entire point of the Hyperloop is to get around right of way and politics.

That is it's design. That is exactly what Elon is doing.

You might argue it can't do what it's setting out to achieve, but this has never been a technological solution.

He's designed a technology to fit with current societal processes rather than the old, get society to accept a technology.

Re: Hyperloop: Pipes of Fancy

#132

Post by titzer »

owenversteeg wrote: post #47
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.

That "Gadgetbahn" article is great, but I do have one criticism. From the article: "If the idea is viable and the people behind it are competent, it should have attracted private investment, as there should be a potential to make profit selling the technology. After all, the proposal has been around for 23 years." High speed rail on a large scale is really something that has to come from the government. While there a…

> The uncomfortable part of HSR, of course, is that no matter how perfect your government is, it's going to involve bulldozing some people's homes, conflicting with other government projects, and interfering with nature. Don't get me wrong, I'm not part of team "screw the law, bulldoze straight lines between cities, people and nature be damned". But there do need to be sacrifices made. And a strong, coordinated government can pass the laws and write the checks to make that happen.

It's worth pointing out that since the 1950s the government has been doing just that and more to build the vast network of interstate highways and state roads. People don't bat an eyelash at demolishing nature for a monster interchange, but propose more rail and suddenly it's so important to consider the environmental impacts and the eminent domain issues.

Re: Hyperloop: Pipes of Fancy

#133

Post by jojobas »

keenmaster wrote: post #121
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.

>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. I disagree with your conclusion. Hyperloop technology is so lucrative that it might galvanize America to update its…

High speed rail infringe mostly on planes' territory, not cars'.

At 3x of bullet trains speed a curve radius of 2500m resolves to 2g lateral acceleration.

For all purposes Hyperloop is very much like Theranos.

Re: Hyperloop: Pipes of Fancy

#134

Post by ClumsyPilot »

chrisco255 wrote: post #124
godtoldmetodoit wrote: post #92

Earlier quoted context omitted.

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?

Hyperloop is not a full vacuum, only partial vacuum if I'm not mistaken. I don't know what kind of difference that would make on pressure but I assume that means that the tubes are not air tight and actually breathe.

Hyper-loop requires 99.99% of the air to be removed from the tube, so it is complete vacuum from the lethality / safety and structure / pressure perspective.

I am not sure what do you mean by 'ubes are not air tight and actually breathe', but they definitely are not air permeable.

Re: Hyperloop: Pipes of Fancy

#135

Post by owenversteeg »

privong wrote: post #118
owenversteeg wrote: post #47

Earlier quoted context omitted.

That "Gadgetbahn" article is great, but I do have one criticism. From the article: "If the idea is viable and the people behind it are competent, it should have attracted private investment, as there should be a potential to make profit selling the technology. After all, the proposal has been around for 23 years." High speed rail on a large scale is really something that has to come from the government. While there a…

> the TGV is also profitable Correct me if I’m wrong, but my impression is that this is only true if one excludes the capital costs associated with the railroad (tracks, right of way, and I think also rolling stock). If you factor in the infrastructure construction costs (and reasonable lifetimes for replacing rolling stock), a high speed trail line will never be profitable without significantly higher fare prices th…

As far as I know, the TGV is indeed profitable even subtracting that. I believe the maintenance of the tracks falls under SNCF Réseau (owned by SNCF) and the rolling stock falls under SNCF.

Figures for the profitability of the individual lines, with construction costs included, can be found here [0] in French. You'll see several lines with yearly rates of return in the ~7-15% range depending on how you measure things. I'd call that excellent, especially given that there are other massive benefits (environmental, health, safety, national security etc) involved that are not included in that calculation.

That said, I may be forgetting to include something, so I may be wrong. But, like you said, only further supports the point that high speed rail can only be accomplished with government input :)

[0] http://geoconfluences.ens-lyon.fr/informations-scientifiques...

Re: Hyperloop: Pipes of Fancy

#136

Post by manigandham »

The vac-train concept is from 1799. Maglev tech is decades in production. I remember a Discovery Channel show 20 years ago about trains traveling 5000mph through tunnels at the bottom of the ocean to cross continents in an hour.

Hyperloop is fantastical renaming of old tech without solving any of the fundamental problems of economy, geography, energy and politics. We're capable of building incredible projects if only we had unlimited funding and will.

It's nice to see Tesla and Spacex changing global transportation so maybe better train systems will finally get some attention, but right now this is just not realistic.

Re: Hyperloop: Pipes of Fancy

#137

Post by jeffreyrogers »

riffic wrote: post #65
jeffreyrogers wrote: post #5

Hyperloop has sex appeal, but it seems like Maglev or just plain old high speed rail makes more sense from an economics perspective. I can't imagine it's cheap to keep a tube evacuated. Either way, it seems good to try and build these sort of high-tech industries in the US.

common misconception. Hyperloop tubes were never meant to be fully evacuated, they operate at pressure differentials with air bearings (imagine a cylindrical air hockey table).

The only thing I can find which specifically mentions a pressure says 1 millibar, which is quite low.[0] The pressurization/depressurization cycle will also fatigue the pods, which will reduce their life-expectancy.

[0]: https://www.pbs.org/wgbh/nova/article/hyperloop-and-high-spe...

Re: Hyperloop: Pipes of Fancy

#138

Post by 9nGQluzmnq3M »

Animats wrote: post #13

The Dubai hyperloop project is supposedly proceeding. The 10km test track was supposed to open this year. Can't find any info later than January 2020. The Dubai to Abu Dhabi link is the ideal case. The route is mostly flat, open desert. Funding is available. There is government support. There's considerable traffic between those points. If that doesn't work, not much else will.

If built, it would compete directly with Etihad Rail, which is building a regular rail network throughout the entire UAE and already has its first phase operational:

https://en.wikipedia.org/wiki/Etihad_Rail

This focuses primarily on cargo, but is built with passenger trains at up to 200 km/h in mind. And most Hyperloop business plans also seem to rely heavily on freight.

Re: Hyperloop: Pipes of Fancy

#139

Post by pilaf »

sudosysgen wrote: post #108

https://www.youtube.com/watch?v=4dn6ZVpJLxs This video has most of the points about why the Hyperloop is a ridiculous idea that will never work.

That video doesn't talk about the Hyperloop at all. You're getting the Boring Company's Loop mixed up with the Hyperloop, which despite the similar-sounding names have close to no relation.

Re: Hyperloop: Pipes of Fancy

#140

Post by ClumsyPilot »

Ajedi32 wrote: post #119
sudosysgen wrote: post #106

Earlier quoted context omitted.

Our subway system in Montreal runs at a frequency of anywhere from 2 minutes to 7 minutes. There are even faster ones.

That's still 2 to 7 minutes longer than a Loop tunnel. And that also only addresses half of the GP's comment (scheduling).

Is it really 2 minutes longer? Subways move millions of people a day. Your loop tunnel will have 1/100th of that capacity. There will be no traffic jams, waiting at the elevators, to merge / separate traffic? Are you addressing some fantasy scenario where you are the only person using a city-wide system?
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