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?
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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.
A million times this. Mag-lev only works for either super dense routes where the added cost as you describe can be displaced by the immense value add of shorter and generally more comfortable travel. Or in nations that can force through decisions from the top down, such that cost becomes almost a non-factor like China. Rail in general across the western world is a weird mix of nationalized and privately owned companies and operators, such that introducing mag-lev with the intent to replace conventional rail would require compensation to the private companies who have invested billions in the current infrastructure else they simply won’t be part of the new one, with all the issues that entail.
From an environmental standpoint it’s also really hard to see an ROI in scrapping something that works in favor of mining, constructing and spending intense amounts of energy in all forms to build something better but only moderately so. The biggest improvement is moving from trucks to (electric) train for freight, going from electric train to mag-lev is only slightly better so the ROI just won’t be there.
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.
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.
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.
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
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.
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)
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.
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.
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.
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. The 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.
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.
maglevs arent using fuckin superconducters to levitate, it’s basic magnetic repulsion. Get whatever fictional version you’ve got in your head cleared up.
Both of you guys are correct, because there are two types of maglev trains; the Japanese tech (Shinkansen) and the German design (trans rapid).
I didn’t even know Germany designed maglev train tech, usually when these trains are mentioned it’s related to Japan or China. Interesting
They absolutely can, the one currently being built in Japan does: http://www.ejrcf.or.jp/jrtr/jrtr68/pdf/14-25.pdf page 19-20
Here’s the one I was thinking of, superconducting magnets for the japanese one SCMaglev https://youtu.be/XjwF-STGtfE?si=jrnttpIrmHBXMtUF
They’re very expensive to build. That’s it, really.
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.
If we somehow remove the friction of air on train body. Then maglev would be zero friction transport.
if only this was a proposed technology
The infrastructure is expensive. The rails are not just a bunch of steel girders. They have to be made of concrete with special magnets inside of it over the entire track. Often they need to be raised
They’re quite expensive for a start and standard HSR does it’s job just fine.
Japan is the only country that’s building actual Maglev lines. It’s feasible in Japan due to popularity of rail and distance between the endpoints makes it worth it.
China has Maglev tech and also some demo Maglev lines. But they are committed to standard rail because it’s cheaper to build using a standardised process and works good enough on large distance travel required in China.
In the US, it’s nearly impossible because Petroleum companies and such hate the idea of cheap and efficient transport and just bribe the politicians to be against it.
I rode the maglev to the shanghai airport, it was awesome. The newer version in Beijing is significantly faster. But yeah super expensive to build.
How was the ride? Smooth/bumpy/not feel much movement?
My experience on a much slower HSR is being thrown around in the seat at certain times, wouldn’t want to be carrying an open drink of any kind tbh lol
because cars cars cars
More likely just the shear cost of building the tracks.
oh yeah, definitely just prohibitive cost