Big tube in the air rests on pylons / support towers. Maybe goes along a highway. Vehicle inside the tube has batteries for running a compressor. It pumps air away from its front to reduce air resistance, pumps below for suspension and behind. High subsonic speed (~700 mi/hr, 1100 km/hr). Accelerated by occasional linear induction motors on the tube, like a maglev train. Vehicle estimated to cost millions, tube estimated to cost billions. Conventional rails cost tens of billions. That's all from the abstract, much more inside.
I thought this was an interesting critical take. Portions are certainly mind-killing, eg you can completely ignore everything he says about rich entrepreneurs, but overall it seemed sound. Especially the proving-too-much argument; the projections involve doing multiple revolutionary things, each of which would be a significant breakthroughs on its own. The fact that Musk isn't putting money into doing any of those suggests it would not be as easy/cheap as predicted (not just in a "add a factor of 5" way, but in a "the current predictions are meaningless" way).
Also, the fact he's proposing it for California seems strange. There are places with cheaper, flatter land where you could do a proof of concept before moving into a politically complicated, expensive, earthquake-prone state like California. I've seen Texas (Houston-Dallas-San Antonio) and Alberta (Edmonton-Calgary) proposed, both of which sound like much better locations.
Some points from the article you linked:
Central Valley land is cheap; pylons are expensive, as can be readily seen by the costs of elevated highways and trains all over the world. The unit costs for viaducts on California HSR, without overhead and management fees, are already several times as high as Musk’s cost: as per PDF-page 15 of the cost overrun breakdown, unit costs for viaducts range from $50 million to $80 million per mile. Overheads and contingencies convert per-mile cost almost perfectly to per-km costs. And yet Musk thinks he can build more than 500 km of viaduct for $2.5 billion, as per PDF-page 28 of his proposal: a tenth the unit cost.
Capacity would be low, and the proposed headway of 30 seconds is unrealistic.
The proposed headway is 30 seconds, for 3,360 passengers per direction per hour. A freeway lane can do better: about 2,000 vehicles, with an average intercity car occupancy of 2. HSR can do 12,000 passengers per direction per hour: 12 trains per hour is possible, and each train can easily fit 1,000 people (the Tokaido Shinkansen tops at 14 tph and 1,323 passengers per train).
Musk's values for HSR energy consumption are not accurate.
However, one thing could not: the chart on PDF-page 9 showing that only the Hyperloop is energy-efficient. The chart has a train consuming nearly 900 megajoules per person for an LA-San Francisco trip, about as much as a car or a plane; this is about 1,300 kJ per passenger-km. This may be true of Amtrak’s diesel locomotives; but energy consumption for HSR in Spain is on average 73 Watt-hour (263 kJ) per passenger-km (see PDF-page 17 on a UIC paper on the subject of HSR carbon emissions), one fifth as much as Tesla claims.
An interesting bit about the economics of it:
By building it on pylons, you can almost entirely avoid the need to buy land by following alongside the mostly very straight California Interstate 5 highway, with only minor deviations when the highway makes a sharp turn.
The pylons are the single biggest cost, but by building it this way, they can avoid almost all the expense and delays that come from buying land and trying to get a right-of-way -- they can just use one that already exists. Upon hearing this, the cost estimates no longer sound too good to be true.
This is one of the places where I'm skeptical; I anticipate a lot of people would have issues with this thing passing overhead, and I have my doubts that they could be overridden, at least without some expensive legal wrangling. I admit I'm not quite clear on how rights for things like power lines work; I realize that those do get built, despite there no doubt being plenty of people who would happily oppose that if they could, but these tubes would be substantially larger than power lines, and I expect the opposition would scale up similarly.
I expect p>0.99 the cost projections are underestimates, p>0.5 by at least an order of magnitude.
This could be really, really disruptive. Build it big enough to move cars, and it kills not only trains and civilian flight, it kills the intercity highway. There is no longer any point to having them, as driving aboard a shuttle is so much faster. It also makes city centers closer to each other (in terms of travel time) than they are to their own exurbs. That is going to be stupidly huge, culturally.
Other predictions: Musk is seeing this as solar powered. Yhea, no. It's electric, its going to run of whatever mix the local grid runs on.
Musk is not going to be the mover behind construction. Most likely first mover: Governments. China, Japan, Europe.. (hey, this could seriously put an end to this bloody crisis!)
Lower confidence: Someone is going to try to make a version of this that crosses ocean. If that works out, civil avionics and shipping are done. Stick a fork in them.
You should probably separate out 3 different aspects of the questions- Musk's personal desires, the technical feasibility, and the political/economic feasibility.
Elon Musk has said that he has no interest in creating a working hyperloop himself, and therefore made the design open source. This strikes me as an uninteresting question.
The technical issues are fairly likely to be more-or-less settled within the next year.
The prediction they're interested in, I think, is whether anybody will create a working hyperloop. Or, possibly, anybody in California- p(China, Japan, the EU, or India create a working hyperloop by 2100|the basic ideas behind the hyperloop are sound and there is no global catastrophe) strikes me as uncontroversially close to one.
Close to one? So the probability that some cheaper/better alternative that we're not considering is developed before anyone gets around to building the hyperloop is close to zero? That doesn't look uncontroversial to me.
Once the first plans for a hyperloop are finished, then the inertia of the project will almost certainly carry it forwards. In China, it currently only takes around a year for railroads to reach this stage, so we shouldn't expect it to take long.
There have been no major new innovations in transportation in the past century, since the car and airplane. It seems like this is due to solid structural and technological reasons, that have if anything only grown larger as the present types of technologies grew more entrenched in society. (e.g. the sheer amount of money needed for new infrastructure; the time construction takes- patents last for 20 years, while the Big Dig lasted for 25; the development of the technology and infrastructure behind cars, trains, and planes). All previous new transportation technologies besides the hyperloop have been preceded by extensive experimentation and many failures; we do not see anything like this today. Planes and cars, during their initial introduction, were less efficient than traditional travel, and it took decades (ish) for them to catch up; in contrast, a hyperloop (again, assuming the ideas presented in Musk's analysis are sound) is better than current tech already- meaning any new competitor would take even longer to catch up. Furthermore, different transportation technologies make sense to use for different distances; anything new would have to be an enormous disruption, to replace transit across the entire range of distances a hyperloop would travel. What's more, the hyperloop is open source, whereas any replacement is very unlikely to be so; even if something that looked likely to probably be better were announced tomorrow, China or Russia would, IMHO, be fairly likely to bring a hyperloop to at least the testing stage in an effort to explore options and to avoid dependence on foreign patent owners- the LA-SF hyperloop's expected costs are only 2% of China's most recent railroad investment plan, it would be cheaper in China, and a testing prototype would be much cheaper. So anything new would have to be significantly better almost immediately and come out of nowhere.
Elon Musk/hyperloop appears to be an exception to the above. As predicted, though, Musk will not be making a profit from this. And he is arguably the only person in his reference class- i.e. very wealthy, technically competent people who focus on new innovations in transportation (c.f. Tesla and SpaceX).
ETA: By analogy, unless in the scenario I've outlined you would expect all construction of train lines, including those already designed, to be halted within the next year or two, you should also expect the hyperloop to be built unless the hypothetical replacement is announced soon and is much, much better.
"There have been no major new innovations in transportation in the past century, since the car and airplane." Drones, jet engine, viable CVT, ICBM, space shuttle, maglev, turbine cars, nuclear-powered engines, helicopter, hovercraft, jet ski, snowmobile...
Today's automobile technology is vastly superior to a century ago, in power, speed, efficiency, and safety.
None of those are 'major innovations in transportation', as is clearly demonstrated by the fact that most people do not ride ICBM's to work everyday, the fact that automobiles had almost entirely replaced horses before CVT and turbines, and the fact that planes had partially replaced ocean liners before jet engines. (In fact, some pre-WWII planes are still in everyday commercial use today.) You are likely confusing 'major innovations' in the sense of technical accomplishments with 'major innovations' in the sense of innovations that had a large impact on society. While new technologies are fun to think about, only the latter definition is relevant.
Today's automobile technology is vastly superior to a century ago, in power, speed, efficiency, and safety.
Incremental improvement != major innovations. If anything, the incremental development of automobiles is evidence against major new innovations, as argued above.
People didn't drive cars to work a hundred years ago, either. And today,there are people drive through the Chunnel to work every day. "Innovation" does not have an established meaning of "something people ride to work everyday[sic]". If you're going to dismiss disagreements with a claim by appealing to a personal, non-explicit definition of a term used in the claim, then I don't see the point of making the claim in the first place; a claim is useful only if the claim is phrased with sufficient clarity that people will know what would be a rebuttal of the claim. I don't see how something ceases to be an innovation if it accomplished through incremental improvement. Can the same technological improvement be an innovation in one universe where it was developed all at once, and not an innovation in another universe where it was developed over a century? Automobile technology has incrementally increased over the last several hundred years. There was no sudden massive jump in the technology, but you seem to consider the transition from novelty to dominant mode of transportation to be a distinctive category of "innovation". If technology X starts out costing 10 times as much as technology Y, and there are 100 different improvements in technology that each decrease the cost of technology X by 5%, is the 45th improvement an "innovation", and the rest not? If technology X cost 1.1 as much as technology Y, and the cost of technology Y suddenly jumps by 15% and technology X therefore supplants technology Y, is that an innovation? You seem to think that "automobile" is an innovation, when a car, at its most basic, is simply a locomotive that isn't run on rails. Why is going from "steam engine than runs on rail" to "steam engine that doesn't run on rails" an innovation, but going from a steam engine that doesn't run on rails, to what we have today, isn't?
Do you know how Air Force pilots based in America get to Afghanistan? They don't. They remote-pilot drones without ever leaving the US. That sounds rather innovative to me. And something that obviates the need for any US-to-Afghanistan hyperloop for these pilots. This discussion got started by your condition that "the basic ideas behind the hyperloop are sound and there is no global catastrophe". What does "sound" mean? Presumably, it means that the hyperloop is cost-effective. And cost-effectiveness is something that depends on the cost of the alternatives, without any respect for whether those alternatives are "innovations" (however you define the term) or "incremental improvement".
This was all addressed in Protagoras's comment and my reply. Please recall that I was responding to a comment proposing that "that some cheaper/better alternative that we're not considering [might be] developed before anyone gets around to building the hyperloop"; I am not the one who is defining the scale of innovation necessary. Obviously, "driving a car with CVT" is not an alternative to "driving a car," and helicopters are not a generally better transportation technology than cars/trains/plane. (It's better in a few specific situations, but obviously for the ancestor's claim that a "better alternative" would be sufficient to prevent a hyperloop from being built, better needs to be interpreted broadly, in the sense that cars are better than a horse and buggy.) I feel like it's pretty reasonable for me to have assumed that readers would have read the comment I was replying to.
Oil pipeline construction companies will be the first to move, using their relevant technical expertise and government connections to obtain funding.
One of the first really big (>5bn$) hyperloops will go across a body of water, using budgeting channels previously used for really long bridges.
PredictionBook: One of the first really big (>5bn$) hyperloops will go across a body of water
(wasn't sure how best to make a prediction out of the other one).
The main problem for this type of project is getting environmental and safety clearance and land rights. A particular problem with building in California is that the government there has pushed hard on their questionable HSR project and they might not want competition. There is also now a set of people who have a vested interest in keeping HSR going and won't like the idea of scrapping HSR for hyperloop.
On the other hand, Musk seems to have a lot of clout in California, so maybe it makes more sense to make his push there. If it doesn't work out for California, I hope he or someone else gets the project rolling somewhere. Texas might be a good candidate, since it has a fast-increasing population and is generally more pro-development than California.
A bunch of safety issues come to mind.
For example, what happens if the tube re-pressurizes due to a crack or something like that? The capsule flies into dense air at 700 mph and, um, that's all she wrote. There's another capsule doing 700 mph behind it, can you brake it in time?
This is addressed in section 4.
A minor depressurization of the tube is unlikely to affect Hyperloop capsules or passengers and would likely be overcome by increased vacuum pump power. Any minor tube leaks could then be repaired during standard maintenance. In the event of a large scale leak, pressure sensors located along the tube would automatically communicate with all capsules to deploy their emergency mechanical braking systems.
(The capsules would be around 6 miles apart at their top speed.)
When and if a hyperloop-like transit system is built (or not), the US will not be the first country to build it. Probably not even in the top 3.
This post reads as though it's saying "Hey, you know that hyperloop thing that we've been talking about all this time? They finally announced it!". Is that the intended meaning?
I was studying in the LW Study Hall, and during our break someone posted this link to the official hyperloop announcement:
http://www.spacex.com/sites/spacex/files/hyperloop_alpha-20130812.pdf
One member was doubtful it would get past regulations, and another said "tentative p>0.05 that a hyperloop gets made by 2100", which was met with "p>0.05 that uploading people and moving them between bodies will be available by 2100".
It struck me that people might be interested in betting on things like this, or at least having a conversation about it.
A few predictions to start: