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Transport Expert Insists 'Don't Dismiss Wacky Hyperloop'

DavidGilbert99 writes "Since Elon Musk announced the details of Hyperloop earlier this week, we've seen a number of experts debunking the technology involved, but at least one is more upbeat about the possibility of 600MPH train travel. Speaking to Alistair Charlton at IBTimes UK, professor Phil Blythe from the Institute of Engineering and Technology said: 'My gut feeling is, don't dismiss it out of hand just because it sounds a bit wacky,' adding 'You're always going to have long distance travel, and if there was something that could replace air travel between cities and hubs, and is low carbon [with] low energy requirements, it make sense to explore it, it really does.'"

16 of 385 comments (clear)

  1. Sure it's a loopy idea by serviscope_minor · · Score: 5, Interesting

    It is a loopy idea, but not fundementally unsound in any way.

    Every aspect of it, from the induction motors, to the earthquake proofing to the aerodynamics to the solar power is all well understood.

    The difficult bit is really the engineering on a large project and developing all the parts and actually building the thing. I wouldn't trust most people with it and the usual suspects for government contacting would surely make a massice hash of it and cause a 50x budget overrun.

    But that's nothing to do with the project per-se. Musk does have the kind of track record showing he can pull off big, complex engineering projects which are generally regarded as difficult and expensive applications of existing tech. Not only pull them off but do them well, quickly and cheaply.

    So please, don't bring up arichair engineer objections to the design without first reading that big, long document which covers most of them and actually providing some reasoning.

    --
    SJW n. One who posts facts.
    1. Re:Sure it's a loopy idea by beelsebob · · Score: 5, Interesting

      Land is going to be what kills this project, before it even gets as far as anything technical. How do you acquire the land for the route as a private entity, without eminent domain?

      If you had even read the basic media coverage of this, you would know that he is proposing mounting this over the central reservation on freeways, so no land purchasing would be necessary.

    2. Re:Sure it's a loopy idea by rasmusbr · · Score: 4, Interesting

      Land is going to be what kills this project, before it even gets as far as anything technical. How do you acquire the land for the route as a private entity, without eminent domain?

      Why would you?

      There are 200+ national governments out there. Convince one of them that it makes sense partnering with you. Once the first hyperloop system is built other governments will follow, including the state of California sooner or later, assuming the system is vastly better than high speed rail. Governments are pretty thick but most of them won't turn down an obviously awesome offer that's going to create profits for businesses and jobs for citizens.

      It does need to be really good to overcome the inertia of government stupidity coupled with big corporate lobbyism. There is already a maglev system called Transrapid that is somewhat better than HSR in almost every way (50% faster, slightly cheaper to operate, etc), but governments prefer to build steel on rails because it brings profit to several existing large corporations and their many lobbyists, as opposed to bringing profit to just the corporation that owns Transrapid and their (fewer) lobbyists.

    3. Re:Sure it's a loopy idea by beelsebob · · Score: 4, Interesting

      Why would you go anywhere near Santa Clara? The proposal is to go up the I5. And no one claimed there would be no deviation from the freeway, just only minor deviation. If you'd actually read the documentation you'd also see that where you do deviate the issue is far less of an issue than for a conventional railway, because being mid-air, the farmer only has to put up with a few pylons being placed in his field, rather than a 30m wide swath that he can't cross. The bottom line is that it is substantially easier to get this across the country, and requires substantially less land purchasing. Where it does involve land purchasing, it's much easier to convince the owners that it's okay, due to not cutting their land in half, and not taking a large section of it; and it's substantially cheaper because you only need to buy the land to site the pylon bases.

      Generally, it's a win all round compared to railways.

    4. Re:Sure it's a loopy idea by fearofcarpet · · Score: 4, Interesting

      I'm not an armchair engineer, but I am a real scientist. And while I have never seen anything at this scale, I have read a lot of proposals. This one did not set off my general bullshit alarm.

      I really, really like that Musk has everyone talking about the Hyperloop and the ancillary discussions of public transportation in general, but there are a couple of details that are glossed over in the big, long document. One is the acceleration/braking by linear induction motors. Correct me if I'm wrong, but he seems to jump from idea that they already work in rotary engines and that MVA inverters are already commercialized (in mining equipment and trains) to the conclusion that they therefore will work in the linear configuration shown in the document. The wording there was sneaky.

      The second is holding a vacuum, ~0.001 Atm., through the whole tube. Has that ever been demonstrated on such a large scale? He shows some metrics from commercial pumps, but then seems to assume that they will scale constantly with volume... how many pumps? Spaced how? What sort of maintenance requirements? How long to pump down the shunts at stations where modules are loaded/unloaded? Vacuum is non-trivial at commercial scales. Perhaps this sort of thing is commonplace and I have just never seen it (and I have seen vacuum chambers that would accommodate a pickup truck). But it felt to me like he was making a lot of assumptions about how easy it is to work with vacuum at those scales.

      Those are both issues that can be demonstrated/prototyped, but it is as naive to say that the proposal was anything more than a whitepaper as it is to dismiss the whole thing out of hand.

      --
      Actually, I wrote my thesis on life experience.
    5. Re:Sure it's a loopy idea by nojayuk · · Score: 5, Interesting

      The Japanese maglev testbed runs at 500km/h regularly, with record speeds of over 550km/h in open running, not in a vacuum tube. Most TGV/HSR/shinkansen fast rail tops out at about 320km/h -- I think there's some Chinese HSR that goes a bit faster on scheduled runs. The planned Tokyo-Nagoya maglev will start operating at 500km/h but they're laying out the track to go faster in the future as the engineering improves. That's not "slightly faster" than TGV.

      Freight doesn't run on LGV, or if it does then the operators are crazy. Heavy freight cars would destroy the track which is optimised for high-speed passenger transport and slower freights would collapse the passenger scheduling to the point where delays and cancellations would be frequent, not a good selling point for HSR. I've made a lot of shinkansen trips over the past few years, only once did I end up on a delayed train. The rest arrived and departed on schedule to the second (and I mean that, the second-hand on the platform clock reaches "12" and the train starts moving.)

    6. Re:Sure it's a loopy idea by bondsbw · · Score: 4, Interesting

      Ever considered underneath the ocean? We are talking about connecting cities that are on the coast.

      --
      All my liberal friends think I'm a conservative, all my conservative friends think I'm a liberal.
    7. Re:Sure it's a loopy idea by tibit · · Score: 3, Interesting

      There would be no attendant - what for, you can't walk inside of one anyway. Those are sit-only capsules. You probably can't exit your seat at all.

      When it comes to emergency response, the default scenario is to reach the destination if mechanically possible. The whole system is designed to complete the journey of all capsules enroute with no external power and no sunlight - there's a lot of power-smoothing batteries at the accelerator sites. They have enough power not only for propulsion, but also to run all of the other systems, possibly for hours. If there was a local blackout, the stations would likely stay up as if nothing happened, the capsule traffic would merely be halted if there was no sunlight.

      If further traver is not mechanically possible (many reasons here), the solution is to (mechanically) brake and crawl to the nearest station or emergency access point. There will be small electric motors and wheels to push you along at a modest pace (say 60mph?). The tube repressurization is a passive thing, so not a big concern - if a capsule signals that the onboard life support is down and the backups are down as well, a bunch of valves open and that's the end of it. Probably the repressurization could also be used as a stand-in for mechanical braking; the air-induced drag would surely stop the capsule rather quickly. A failure of the compressor would do the same thing although probably too slowly, there's storage for gas bearing air such that whatever braking mode is used, the gas bearings wouldn't run dry, so to speak. I'm sure the system would be engineered to behave. That's what engineering is for.

      The whole "trapped passengers" issue is I'd think a bit overblown. The major active systems in a capsule are mostly not unlike those on a locomotive and on an airplane: a compressor, an electric motor, control and power electronics, a battery bank. Propulsion is external - the capsule merely has an aluminum stator sticking out from it. Due to low drag, the capsule is coasting without propulsion for 98% of the length of the route. For it to keep coasting, the compressor needs to keep on spinning, and you must have no leaks in the water coolant loops. They're not sure yet to what extent the active tilt control would be used.

      The idea is nifty, and it's sorely needed. I think that if nobody else in the western world would pick it up, we'll end up seeing it somewhere in Asia. I'd like to be among the first passengers once it's open to the public :)

      --
      A successful API design takes a mixture of software design and pedagogy.
    8. Re:Sure it's a loopy idea by tibit · · Score: 4, Interesting

      Correct me if I'm wrong, but he seems to jump from idea that they already work in rotary engines and that MVA inverters are already commercialized (in mining equipment and trains) to the conclusion that they therefore will work in the linear configuration shown in the document. The wording there was sneaky.

      An acquaintance has a small demo unit made as an (expensive) novelty item sitting on his desk. It's an aluminum pendulum and a 3 phase linear motor (just because, as he says). Runs off a couple AA rechargeable batteries. The pendulum is a disk and can be converted to a balanced disk by removing a weight. Once converted, you flip a switch and instead of going back-and-frth, it can spin up to 20kRPM in about a minute. The configuration is entirely immaterial, it's really a very basic thing, electrodynamically speaking. After you press the brake button, it similarly stops in about 40 seconds, while recharging the batteries.

      --
      A successful API design takes a mixture of software design and pedagogy.
  2. Indeed ... by golodh · · Score: 3, Interesting
    Perhaps prof. Blythe was thinking of the Swissmetro project (see http://en.wikipedia.org/wiki/Swissmetro ) which proposed to build high-speed train connections through low-pressure tunnels.

    That project was reported to be both technically and economically feasible despite the handicap of having to tunnel all the way through granite. Apparently the project died for lack of interest and political will to see it through.

    So, what people refer to as "Elon Musk's idea" really isn't new and also isn't nearly as wacky as some people seen to think. The thing that Elon Musk seems to be adding is marketing and PR. Perhaps that will make the difference.

    1. Re:Indeed ... by squiggleslash · · Score: 3, Interesting

      The more I've read about the proposal the more I think Musk is being deliberately deceitful and disingenuous, so "Elon Musk claims"... should be interpreted in a different light.

      Just a recap:

      1. The proposed hyperloop doesn't serve all of the cities that the HSR proposal does.
      2. The proposed hyperloop requires an hour of transportation or more at both ends because it doesn't terminate anywhere near SF or LA. Meaning travel by Hyperloop will take longer than HSR in most cases.
      3. The proposed hyperloop is supposedly a viaduct that can be built for $5M/mile. Either it is, in which case that's one cheap viaduct, and also a way HSR could be built more cheaply, or it isn't and it'll cost ten times that, like normal viaducts do.
      4. The proposal makes outrageous and ridiculous claims about the energy efficiency of HSR, estimating it at being around 3x real world HSR systems use.
      5. The "cheap" version of the Hyperloop will be cramped, like air travel.

      It's usual for opponents of transit systems to pretend to be pro-transit and then um and ah about the costs, whittling down the proposal to something that nobody wants, "Oh, we know light rail would be popular and is exactly what this town needs, but, well, it's just very expensive, and a Bus Rapid Transit system would at least do most of what light rail is for, but at a fraction of the cost", and they make these arguments and finally the pro-transit people give in, recognizing that the fake proposal is better than nothing: and then it's put to the voters who vote against because it's a FUCKING BUS.

      And here we have the same on a larger scale. In five years Elon Musk is proposing to build a giant viaduct at a fraction of the cost of any viaduct known to man using technologies that have never been used that doesn't go anywhere instead of that big expensive rail system everyone wants.

      He's not trying to introduce a revolutionary new form of transport. He's trying to kill a legitimate rail project.

      And if he said "Listen, I think HSR is too expensive, we should concentrate on improving our airports and roadways" I'd at least have some respect for him. But he's lying, he's telling lies to try to get the result he wants. What a slimeball.

      --
      You are not alone. This is not normal. None of this is normal.
  3. Re:10% of the capacity of high-speed rail by Rakishi · · Score: 2, Interesting

    That blog fucked up the numbers. They apparently don't understand the difference between "normal breaking" and "emergency breaking."

    The capacity of the hyperloop is 25% of high speed rail and one can question how realistic the high speed rail numbers are. Maximum capacity of X is utterly useless if you'll never reach close to it.

  4. There are easier ways to use renewables. by 140Mandak262Jamuna · · Score: 3, Interesting

    Blythe believes the long term success of Hyperloop will lie in its ability to be powered entirely by solar panels. "The compelling argument today is that the energy to run this could be generated from renewable resources, so the energy cost and the CO2 emissions are low - that probably gives it a bit more of an interesting argument whereas 15 years ago we didn't care about stuff like that.

    But it far cheaper to electrify a conventional train track. And far cheaper to install just solar panels on top of all highways and rail tracks. In fact if we put a "roof" over all the highways in the northeast and install solar panels on them, the savings in snow removal costs in winter and the electricity generated in summer could pay for the whole project. Putting gables over highways and directing the snow to fall on the sides instead of on the lanes is a far cheaper project than this.

    The home construction industry still reeling from the 2008 financial shock could use a shot in the arm. Regular conventional structures, gables and trusses, oriented to face the South, over I-90 between NewYork and Boston. Why not? We shoveled 800 billion dollars to the greedy banksters in just three months in 2008. A steady 10 billion dollar a year to put roof over highways is probably a better idea.

    --
    sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
  5. Re:10% of the capacity of high-speed rail by Rakishi · · Score: 4, Interesting

    The maps Musk released show the system travelling from the fringes of the Bay Area to the fringes of the LA area, because it's hard/expensive/impossible to get land for the straightaways you'd need for the project within densely built up urban areas.

    Most people in the Bay Area do not live or work in SF. In fact San Jose which is the south end of the Bay Area alone has almost 1 million people (and growing) compared to 800k in San Francisco (and not growing).

    Not coincidentally, must of the construction and expense that adds to HSR's very high price tag will come in SF and LA urban areas, since that system goes from downtown to downtown.

    That's because HSR needs to go to downtown to be even remotely competitive with airlines and thus viable. It's so much slower than an airplane it just can't be remotely as fast unless you add in all the commuting to station/airport time. The Hyperloop does not. It is as fast as an airplane if not faster. That's from station/airport to station/airport. So it can be just as fast an an airplane destination to destination despite not going to downtown since airports also don't go directly to downtown. If people care later on it can be expanded but initially it can compete on price for example.

  6. Re:OTOH by Nexus7 · · Score: 3, Interesting

    The cheapest way to move people intercity is steel wheel on steel rail. Any transport expert worth his salt should know that. Why, in Japan, Europe, and China, they're already moving people at over 200 mph average. Today.

    But if you can ignore practical considerations (like "visionary" businessmen can do) because the people (read governments) are willing to let you externalize costs such as land, hazard insurance, accident clean-up costs, etc. then sure, hyper-my-loop away.

  7. Re:OTOH by idontgno · · Score: 3, Interesting

    Well, you have to admit, the current long-distance transport system externalizes the hell out of a lot of effective costs. How much land was condemned to build airports? How much pollution do we basically ignore?

    We should extend any future technologies the same courtesy, lest we erect an unjustifed barrier to market entry. Or else impose full cost-bearing on current market holders. In the interests of leveling the playing field, of course.

    --
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