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?

  • @[email protected]OP
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    121 year 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.

    • @[email protected]
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      201 year ago

      all the other complex and important factors aside, air restistance is a formula of speed squared. Meaning for example if you bump speed up by 40% you double air resistance, and therefore double the energy cost of transport.

      • @breadsmasher
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        131 year ago

        Isn’t that only applicable for identical trains? For sake argument, if you had two identical trains designed with poor aerodynamics, one at 100mph and one at 140mph then you can double the energy cost. But if you take two different trains with one designed to be more aerodynamic, at the same speed they wouldn’t have the same energy cost as the second has a better profile?

        Plus theres less friction from needing to be on a rail.

        So I think saying its double the cost of transport is too simplistic to be meaningful in this discussion

        • @[email protected]
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          91 year ago

          It’s more than that - doubling air resistance only doubles the energy use if it’s the only inefficiency on the train (e.g., no losses in the magnets, HVAC, lighting, etc.). Add onto that the fact that you’re basically eliminating rolling resistance from traditional trains when switching to maglev, and the expected outcome should be much less than double.

          Finally, the most important part, each high speed rail route of any meaningful distance has the opportunity to displace a certain amount of air travel, so big picture, HSR results in a significant decrease in overall energy consumption.

    • @xkforce
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      181 year 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)

    • @Aux
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      21 year 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.

        • @Aux
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          51 year 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.