They were invented decades ago.

They have fewer moving parts than wheelbois.

They require less maintenance.

There’s obviously some bottleneck in expanding maglev technology, but what is it?

  • slazer2au
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    822 years ago

    If you introduce a new rail type into your rail network you can’t use your existing fleet of trains on that section reducing the ROI on that train engine or carriage. Also, any train you purchase for the new rail type will only ever work on that system lowering their profitability in the long term.

    • @Yondoza@sh.itjust.works
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      2 years ago

      Also the fact that ‘less moving parts’ doesn’t mean lower complexity or maintenance cost. Train wheels are a very robust and efficienct mechanism and most train designs are not being limited by them.

      • @Dubious_Fart@lemmy.ml
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        52 years ago

        Very robust because they have 300 years of research, innovation, materials science and manufacturing in them. Making them incredibly stellar, well understood, damn near perfect technology for what they do.

        • lol3droflxp
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          82 years ago

          Also them just being wheels in general which are one of the most efficient and simple ways to move stuff.

      • @user134450@feddit.de
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        2 years ago

        woah this is awesome!

        maglevs need classical wheel systems anyway because there might be a power outage, so simply having wheels that are compatible with the local rail system is a brilliant idea.

        add in a tiny propulsion system so they can use the normal tracks at low speed without the help of the maglev tracks and you can sort of blend the two systems together in critical locations like switches and train stations.

  • Pons_Aelius
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    392 years ago

    The same reason supersonic passenger jets are rare.

    The extra speed comes with a massive increase in costs.

    Travel 30% faster than high speed rail for 10-20 times the cost.

    • @frightful_hobgoblin@lemmy.mlOP
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      112 years ago

      Is the claim about “10-20 times the cost” true? The internet says Shanghai maglev cost $1.33 billion for 30.5 km, i.e. less than $44 million/km. Compare https://transitcosts.com/new-data/ or https://transitcosts.com/high-speed-rail-preliminary-data-analysis/

      Secondly, if it is true, why would it be true? Why would it be more expensive to build something with fewer moving parts?

      Supersonic passeenger jets require more energy. Maglev trains require less energy.

      • @xkforce@lemmy.world
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        82 years ago

        Maglev requires superconductors to work. They must be cooled to just a few degrees above absolute zero (typically ~ -270 celsius) and if they ever warm up beyond their critical temperature, catastrophic failure is the result. (this is called quenching which can destroy the superconductor permanently) So not only can you only drive maglev trains (which are expensive themselves) on maglev track and can only drive mag lev trains on maglev track, its far more expensive to build and maintain superconducting infrastructure than it is to lay down some steel rails. Maglev trains are used because the only friction that they experience is from air resistance. Theyre much faster than normal trains but it takes a lot of energy to keep the superconductor that makes them work cool, costs a lot more to build and requires a lot of electricity to get them up to speed. (They can use regenerative braking to recover much of this but its still an energy intensive process)

      • @JillyB@beehaw.org
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        52 years ago

        Japan is in the late stages of developing a maglev section of the Shinkansen. It has liquid helium cooling for semiconductors and lots of considerations to make sure the cabin and surroundings aren’t exposed to very strong magnetic fields. It’s just more expensive to do all that.

        After Japan rolls this out and works out the kinks, it might get cheaper since a lot of they’ve done a lot of the development.

      • @Aux@lemmy.world
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        12 years ago

        Maglev’s top speed record is just 5% faster than conventional train speed record. Thus if Maglev is more than 5% more expensive, then it doesn’t make any sense to build them.

        • @flux@lemmy.ml
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          12 years ago

          Speed records aren’t usually representative of regular use top speeds, are they?

          • @Aux@lemmy.world
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            12 years ago

            Well, if we look at actual maglev deployments in the real world, then they are much slower than conventional trains. All of them top out at 160kph, while conventional trains going below 200kph don’t even count as high speed. There’s only one Maglev line in the world which actually goes fast. So if we want to talk about regular speed representation, maglevs are slow and useless.

  • Kool_Newt
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    312 years ago

    Because it’s not currently profitable in most cases. Capitalism ensures that the merit of an idea comes secondary to it’s profitability. We don’t get the best things, we get the profitable things.

    • @traches@sh.itjust.works
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      182 years ago

      Not to defend capitalism in general, but it’s really good at answering these sort of “is it worth the cost?” aquestions. The whole point is to allocate scarce resources efficiently; the problem is that it assumes nobody is a scumbag and all the costs are accounted for.

      • Cyclohexane
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        22 years ago

        It isn’t. Most decision makers of capitalism are very unaware of science. You’d know this if you work in research. The ideas that see light of day do so not because they’re good in any quantifiable sense. It is because they convince the capitalists. This can be affected by so many things that aren’t merit or even cost based.

        Some things make sense from a cost perspective, but not a profitability perspective. Profit isn’t just about cost. There’s margins, competition, longevity, etc. Something can be of moderate costs, but if the margins are too low or it is too long term or a project, it is of low value to capitalists.

        • @DogMuffins@discuss.tchncs.de
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          22 years ago

          I’m really struggling to understand what you’re getting at here.

          Whether or not a decision maker is aware of science, their products will still be subject to the laws of physics.

          Some things make sense from a cost perspective, but not a profitability perspective.

          For example?

          • Cyclohexane
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            12 years ago

            To simplify it, when capitalism answers “is it worth the cost?”, it is not answering “is the benefit of this thing to society worth the cost?”. They’re answering “are the profits I would get out of this and the risk worth the cost?”. And profits do not always agree with what’s good for society.

            One example of moderate-to-low cost investments that are of demand in society but not very profitable and hence does not see focus is low-income housing (at least in the US). Housing developments disproportionally target high income or even luxury housing, as the margins on those are far better (but the costs are also much higher). Even nowadays, that this trend has been going on for a while, and luxury housing has really fallen out of demand (which greatly increases the risk), it continues. Luxury housing still looks a better investment to investors, when society does not need more luxury housing. It needs more moderate and low income housing.

      • @gnuhaut@lemmy.ml
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        2 years ago

        Better acceleration, steeper inclines, tighter curves at same speed, better ride quality and less wear. As someone has mentioned below, normal trains could go a lot faster than they do in practice, because the ride quality, wear and wind resistance get atrocious, and the tracks need to be exceptionally straight. Making a maglev go fast is more feasible, though you still have the wind resistance issue obviously.

    • @Joker@beehaw.org
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      52 years ago

      Where are all the maglev trains in non-capitalist countries? Sooner or later, in any system, someone has to do a cost benefit analysis and decide whether it’s worth it. It’s not just about profitability. There are plenty of situations in the US where something is unprofitable but still funded because the benefit is worth it.

    • @teawrecks@sopuli.xyz
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      22 years ago

      It’s basically evolution. It’s not that we don’t get the best things, it’s that when something evolves traits that require more energy than they are worth, they inevitably die out. I’m reminded of the film The Man in the White Suit.

      It’d be nice to always have the “best” things, but the “energy” to support them has to come from somewhere.

      • apotheotic (she/her)
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        22 years ago

        But unfortunately the mechanism that is dictating which traits are carried through and which are left to die out, is capitalism. Not just that, but short sighted capitalism.

        I’m not saying maglev is the be all and end all, I’m just saying that this “evolution” is sort of (extremely) fucked.

        • @teawrecks@sopuli.xyz
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          12 years ago

          True. Similarly, unfortunately the mechanism that is dictating which traits are carried through is natural selection. Maybe this metaverse thing has some benefits after all 😆.

          The way I see it is, if you have a set of entities all acting in their own best interest, the way they engage with each other is called “capitalism”. If a subset of those entities band together to act in the interest of their communal group, the mechanism within the group might be “communism”, but how that group interacts with other entities/groups is still capitalism.

          It’s no coincidence that China, a communist state, is one of the strongest players in the wider capitalist economy. And even if the CCP was 100% benevolent toward everyone, they would still only be able to justify spending that makes sense at the global level. This is why they’ve opted to no longer buy our “recyclables” as raw materials. Sure it would be nice to always recycle stuff, but it was polluting their rivers, costing them more in healthcare.

          At the end of the day, capitalism IS economic natural selection. So I view a government that embraces unchecked capitalism as a government that does nothing.

          I think our best chance is if people to view a maglev train (and the benefits it offers) more like going to the moon: it’s inspirational. It gives people something to look at and say “look how far we’ve come” both figuratively and literally. It’s not impossible to fund, we just need to all value it so much that we’re all willing to divert funds from other places where they probably make more sense, i.e. act in a common interest. But we can’t even do that for healthcare so…

          • apotheotic (she/her)
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            12 years ago

            While I agree and disagree with several parts of your sentiment, asserting that a mechanism fuelled mostly by the 0.1% or 0.01% of its constituents is “natural selection” feels a bit disingenuous. It’s selection, but it doesn’t happen by nature. The driving forces behind a lot of the changes that happen are backed by intent (of the players with the most power), not environmental fitness.

            And calling China a communist state is a disservice to communism, they call themselves communist but its about as apt as trump calling himself a feminist.

    • Chahk
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      22 years ago

      “MVP” stands for “minimum viable product”.

  • Iron Lynx
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    312 years ago
    • construction is Hella pricey
    • there are few maglev manufacturers, allowing vendor locking and exacerbating the first point
    • they must be built grade-separate, which can complicate route planning
    • they are incompatible with existing rail tech, which results in having to build new, expensive infrastructure for 100% of your route, further exacerbating the first point
    • their switches are slow, limiting capacity

    Ultimately, their competition is regular trains, which are simpler, more tolerant to buying from multiple manufacturers, still significantly more efficient and faster than anything roadborne, able to switch over the course of seconds instead of minutes, able to interoperate with different tiers of intensity and speed, able to be built at grade, cheaper and having the better part of two hundred years of technological refinement behind it. Ultimately, maglev has specific, niche advantages that make it a hard sell for any system that already has regular rail.

  • @rufus@discuss.tchncs.de
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    262 years ago

    They’re super expensive. Few people are willing to pay the massive amount extra for the slight dectease in travel time. Investors also know that.

  • @marcos@lemmy.world
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    242 years ago

    Plane maglev tracks are way more expensive than wheeled train tracks. It’s slower to get expensive when the terrain stops being plane, but it takes a lot of roughness for it to become cheaper. Most countries just do without trains crossing rough terrain.

    And the largest cost of almost any train is the tracks.

  • gregorum
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    2 years ago

    Where existing transit infrastructure exists, cities prefer upgrading existing infrastructure, rather than installing new infrastructure in its place, and where transit does not exist cities prefer not to install anything at all and favor cars typically. Maglev trains are extremely expensive to install the infrastructure, so gathering the money out of local budgets to invest in the extremely expensive maglev infrastructure is typically very difficult.

    In the US in particular, politicians, just don’t look at the picture in the long term, and only focus on short term investigator as it pertains to their election schedule, and that is sad and has long-term impact on the local population.

    • Carighan Maconar
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      52 years ago

      Think about it this way, OP: You know when they’re working on the train network, how much you loathe commuting while a single line is out? How much of a pain replacement bus transportation is?

      Now imagine having to do this for all train lines, everywhere, and you always have to switch trains (due to the difference in track) in between the blocks of replaced track. Plus you can’t neatly fit maglev where conventional track fits and vice versa, plus you need the power infrastructure, plus you need to find a way to buy the rolling stock without already selling the old one.

    • @underisk@lemmy.ml
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      32 years ago

      Also for the US the automotive and oil industries have powerful lobbies and an obvious interest in preventing the proliferation of electric-powered public transport. They’ve spent decades centering personal automobiles as the default method of travel and attack these projects with enthusiasm.

  • BarqsHasBite
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    2 years ago

    You still need rubber wheels when it’s stopped and at low speed. They retract when it’s fast enough for the maglev to take over.

    The electrical conductors are expensive as shit. The ones in the train need to be super cooled or something. The track ones need to be built along the entire length. On three sides, one vertically and two horizontally. Along with massive power lines along the whole length. They don’t need to move to be expensive.

    The right of way needs to be very straight. So compared to normal high speed, you have to spend much more on buying land, earth moving, tunneling, etc.

    All this needs to be maintained to an extremely high degree because you can’t accept a failure. The engine on a high speed rail fails and you just slow down, no biggie. HSR track is fairly robust and can easily be inspected visually. Since it has the same base as normal passenger and freight you have an entire industry knowledge and inspection machines. Any part of maglev fails and you have a catastrophic failure.

  • Kyoyeou (Ki jəʊ juː)
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    2 years ago

    What is a Maglev train? (From WIki)

    Maglev (derived from magnetic levitation) is a system of train transportation that uses two sets of electromagnets: one set to repel and push the train up off the track, and another set to move the elevated train ahead, taking advantage of the lack of friction. Such trains rise approximately 10 centimetres (4 in) off the track. There are both high-speed, intercity maglev systems (over 400 kilometres per hour or 250 miles per hour), and low-speed, urban maglev systems (80–200 kilometres per hour or 50–124 miles per hour) under development and being built.

    Why so little?

    Despite over a century of research and development, there are only six operational maglev trains today — three in China, two in South Korea, and one in Japan. Maglev can be hard to economically justify for certain locations, however it has notable benefits over conventional railway systems, which includes lower operating and maintenance costs (with zero rolling friction its parts do not wear out quickly and hence less need to replace parts often), significantly lower odds of derailment (due to its design), an extremely quiet and smooth ride for passengers, little to no air pollution, and the railcars can be built wider and make it more comfortable and spacious for passengers.

    Cute link to the Wikipedia Page

    I am a curious human, beep boop

  • @mondoman712@lemmy.ml
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    92 years ago

    One other thing I’ve not seen mentioned yet is capacity. Switching a maglev track is difficult and very slow, which reduces the number of trains you can get through a switch and therefore the number of people your system can carry.

  • @dkt@lemmy.ml
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    52 years ago

    Here’s an interesting write-up about an attempt to develop a large-scale urban maglev system in the 1970s: https://en.wikipedia.org/wiki/Krauss-Maffei_Transurban

    tl;dr: there were so many technical issues that when the West German company developing the tech lost funding and the Ontario government took over the project, they immediately abandoned the maglev concept and replaced it with linear-induction propulsion with steel wheels on rails (the mag, without the lev).

    Even this tech, which does have a few advantages over conventional rail and is still used today in cities like Vancouver, is falling out of favour due to general logistical issues with using bespoke technology over conventional rail – fewer people know how to build and maintain it, you’re relying on usually just one company to supply your trains and infrastructure until the end of time, you can’t reuse any existing infrastructure, etc. I’d imagine these issues still get in the way of maglev development today – even more so because you can’t even reuse existing rails

  • @mikeboltonshair@sh.itjust.works
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    As others here have already mentioned the infrastructure costs alone are a huge problem, where I live we are currently just trying to electrify the corridor and it’s not even the entire system, once again the overall rail infrastructure is already there (it’s just electrification) yet this is still going to take a minimum of a decade and the minimum cost is going to be more than $11bn, technically this saves money as you don’t need to buy a new fleet of rolling stock just upgrade the old ones.

    So ya for a maglev you would need a completely different infrastructure and the rolling stock

    • Semi-Hemi-Demigod
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      72 years ago

      If it had a significant advantage the expense would be worth it, but steel wheels on steel rails already have a coefficient of friction 10x lower than rubber tires on asphalt, so it’s not worth it.

      • @Candelestine@lemmy.world
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        22 years ago

        You do save money on them in the long-run. I just assume it takes decades to get all that return on investment back out, thus any entity interested mainly in quarterly profits has little incentive to make the investment, which would be disruptive to their finances in the near-term.

          • @Candelestine@lemmy.world
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            12 years ago

            Fewer major repairs is the way they save you money. Fewer moving parts, less friction, less wear and tear. All the energy savings gets tossed out the window in the interest of going faster, in the ones we’ve made so far anyway.

            • lol3droflxp
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              22 years ago

              There may be fewer moving parts but that does not necessarily mean cheaper/less repairs. Current railway parts (especially wheels) are fairly low tech and easily fixed. What if the cooling of a superconducting magnet fails? That’s expensive.

              • @Candelestine@lemmy.world
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                12 years ago

                Sure, I didn’t say they never require maintenance or anything. Simply that over a long period of time they become cheaper to operate, after taking into account repair and replacement costs.

                If you don’t take repair and replacement costs into account, they become more expensive. This is probably another reason there are not many of them. Repair is where they save you the money though, due to how infrequently they require it.