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Hyperloop

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Re: Hyperloop

#411

Post by kalid »

teek wrote: post #363
kalid wrote: post #179

Earlier quoted context omitted.

The same thing that happens when you develop gastric issues on a 30-minute helicopter tour, as the minister in a wedding ceremony, or in a dentist's chair.

Don't forget we're also comparing to HSR. On a train you can go to the toilet anytime you want.

Sure, unless that bathroom is occupied by someone who had gastric issues before you did :).

The meta point: If you can't plan around a 30-minute window of no bathroom access, that biological restriction is a bigger concern than arriving at your destination quickly.

Re: Hyperloop

#412

Post by ibudiallo »

LekkoscPiwa wrote: post #206
aresant wrote: post #32

"In the case of the Hyperloop, Musk started focusing on public transportation after he grew disenchanted with the plans for California’s high-speed rail system." And who says that big government stifles entrepreneurial innovation? If ALL Musk does with the Hyperloop announcement is shed more light on the potential debacle that is to be our $70b+ high-speed rail in California, we owe him a debt of gratitude. PS - Dire…

but why to ask California State for subsidy? Why not to build it using private funds? I'd imagine that if this is economically sound idea there must be potential investors lining up to have their share in the Project? The estimated cost is $7B. Now, Musk just needs to make a few calls to his friends at Google, Amazon, etc. Can't these guys just form a company together just to build it? Maybe I'm naive... or maybe Mus…

Bill gates can reach for his wallet and fund this. He won't even notice it.

Someone get me his phone number right this moment.

Re: Hyperloop

#413

Post by Balgair »

HCIdivision17 wrote: post #326
acadien wrote: post #80

Earlier quoted context omitted.

But that's at a pressure of 100Pa (1/1000 atm). How much power does it take to maintain a vacuum of 1/1000atm in a tube hundreds of miles long? It seems this point is skipped over in the whitepaper, so perhaps its negligible. Edit: yes I was referring to the power to sustain a vacuum in a leaky system, of course no power is required to maintain a vacuum in a perfectly sealed system :)

To me, a 1/1000 atmosphere vacuum system IS a really leaky machine :) Anecdotally, the machine I used to work on would gleefully chew on that for hours idling while we scrambled to find the hiss on the system. It made an awesome sound when it ground into the atmospheric pressure on initial pumpdown, but at about 1/100 atmo it got bored (mere minutes), and without additional high speed stages the mechanical pumps woul…

I used to work with a system of about 1m^3, 2 little mechanical pumps would get you to 10E-6 atm or so. A turbo pump got you down to 10E-9 or there abouts. The door on the thing was about 2.5 feet in diameter, with a big ol' O-ring that would get twisted and tangled all the time (we broke it once, gorilla glue worked just fine to fix it).

I also second the great sound they made. It was like 2 very angry horses going 'Brahbrahbrahbrahbrahrbah...' getting quieter all the time.

If the system will be welded together that'll reduce the leaks quite a bit and the maintenance too, which I think will be the biggest problem. It's not making it work, it's keeping the thing working that will eat up the costs. Eventually, as the thing ages, you'll have bigger and bigger leaks. Figuring out how to deal with that will be a moon-shot on it's own.

Re: Hyperloop

#414

Post by NegativeK »

ars wrote: post #353

"by placing solar panels on top of the tube, the Hyperloop can generate far in excess of the energy needed to operate." He seems to be planning to build this over farmland? Because farmers aren't going to be happy about someone blocking their light. Light is the limiting factor in plant growth. If he's going to block the light to farms he'll have to pay them for the lost crops, and then he might as well just buy the…

If he's going to build it over farmland, whether he uses solar panels or not is irrelevant to the farm. The land would be rented/bought/imminent domained just like normal rail would.

Re: Hyperloop

#416

Post by dragonwriter »

ewoodrich wrote: post #403
afriesh123 wrote: post #376

Earlier quoted context omitted.

BTW - the link disproves your point somewhat - voters approved a $10bn train, which is now expected to cost over 10x that. Brings into question what exactly they approved, or what it means to "approve" if there is no cost control in the approval.

I don't have a point really, I'm just saying this was a publicized ballot measure at the time and not carried out against the voters' will. And as I said in above comment, the $9.95 billion was for the initial bond issuance. The estimate on the ballot was $40 billion versus the current estimate of between $98.5 billion and $118 billion.

> The estimate on the ballot was $40 billion versus the current estimate of between $98.5 billion and $118 billion.

The estimate from the current Business Plan is $68.4 billion, not "between $98.5 and $118 billion."

Re: Hyperloop

#417

Post by qohen »

thrownaway2424 wrote: post #316
spikels wrote: post #245

Earlier quoted context omitted.

As currently envisioned CA HSR is likely to be more expensive and slower than current air travel. This is before the virtually certain cost overruns. To be competitively priced it would require large subsidies but still would be no faster than alternatives. That said like you I would love to see a superior alternative to the current situation but CA HSR is probably not it. Edit: added some references http://www.mercu…

Well, no. You just made that up. HSR is intended to meet a future need for transportation. The equivalent air transportation infrastructure to meet the same need is believed to cost at least $500bn, according to the environmental impact report. That's making the generous assumptions that this level of air travel is even possible without serious air traffic congestion problems, and the aviation fuel costs do not rise…

The main cost of CAHSR will be the opportunity cost of not having built it.

I wonder: this is from an LA Weekly article from 2011 -- I remember it being an eye-opener when I read it back then [1]:

The authority had projected that 41 million people annually would ride the train between Anaheim and San Francisco, for example. But currently only 12 million customers fly nonstop on the extremely busy air route between Los Angeles and San Francisco each year.

The article goes on to say that Acela gets 3 million riders in the very dense east coast NY/Washington corridor but in less-dense California they were projecting a ridership around 10x of Acela's (!).

The LA Weekly has had a bunch of articles about the project over the years criticizing everything from its cost to its leadership to its utility. If the picture they paint is mostly correct, perhaps the only way to win is not to play.

And it's not just the LA Weekly -- a third party independent review came to similar conclusions apparently, as described in this LA Weekly article from Jan. 2012 [2]:

On top of skepticism from the state auditor, inspector general and legislative analyst -- as well as university researchers, federal transportation experts and this very news blog -- a "peer review group" for the California High-Speed Rail Authority, formed for the sole purpose of independent review, has declared the project neither physically nor financially feasible at this time.

The train's roster of supporters tells us everything we need to know:

"The project has won major support from organized labor, some big-city mayors and many state lawmakers," reports the Los Angeles Times today.

The article quotes the following from the report:

"We cannot overemphasize the fact that moving ahead on the HSR project without credible sources of adequate funding, without a definitive business model, without a strategy to maximize the independent utility and value to the State, and without the appropriate management resources, represents an immense financial risk on the part of the state of California."

[1] http://www.laweekly.com/2011-11-24/news/100-billion-bullet-t...

[2] http://blogs.laweekly.com/informer/2012/01/california_bullet...

Re: Hyperloop

#418

Post by dice »

pxtang wrote: post #327
mcintyre1994 wrote: post #301

Earlier quoted context omitted.

I'm not from the area, so I don't know how such a ballot works but for voters who didn't have Musk-level engineering knowledge, was the choice the status quo of not fast trains and spending on fast trains?

IIRC, the choice was between no trains and a train. I think a lot of people voted for it so they had a cheaper alternative than planes and a less time/effort intensive alternative than driving.

Also because fuck the TSA.

Re: Hyperloop

#419

Post by incision »

dkrich wrote: post #231

The main reason why air travel continues to be the most practical, cost-effective means of high-speed transport is that the politics involved in connecting two points with a transit system are enough to make you lose faith in humanity. Take for instance, the DC metro system. There is an expansion underway to extend the system west to Dulles Airport, about 30 miles or so from downtown DC. A huge project, no doubt, but…

>"There is an expansion underway to extend the system west to Dulles Airport, about 30 miles or so from downtown DC. A huge project, no doubt, but it is about ten years behind schedule."

That's a bit of an exaggeration. Construction was scheduled to begin in 2005 and actually got started in 2009 [0]. Also, Metro is something of a special case in general with the system spanning 2 states and the District while having no dedicated source of funding [1].

0: http://en.wikipedia.org/wiki/Silver_Line_(Washington_Metro)#...

1: http://en.wikipedia.org/wiki/Washington_Metropolitan_Area_Tr...

Re: Hyperloop

#420

Post by escoz »

mpyne wrote: post #321
Osmium wrote: post #199

Reading the entire PDF is highly recommended; it contains a surprising amount of answers already (including many to comments below). I think, if anything, safety aspects haven't been sufficiently explored in the pdf. I'm quite happy to believe it's safer than other modes of transport, but I wouldn't be too quick to overstate it. Also, if anyone can explain what "Tubes located on pylons would limit access to the criti…

Indeed, I started getting giddy when he was discussing how to get the best power factor from the stator of the linear induction motor. It's obvious there's been a lot of thought put into this. On the other hand even with a recommendation to use something similar to TSA doing something similar to airport security, his response plan to a terrorist attac--, er, a "human related incident" is basically to say that the sys…

He does mention luggage would be 1) handled by hyperloop employees 2) removed from the pod all at once to be handled at a different time. Probably more like these pods, which are mostly "blast resistant" http://www.freepatentsonline.com/6918501.html
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