MagLev is a lie. There are MagLev (Magnetic Levitation) trains operating. Yes, GE and a consortium build a very nice demonstration train in China. And like many infrastructure projects in China, it's a white elephant. The train was built, but no longer operates.
Someone commented elsewhere the MagLev is the Concorde of passenger trains: something extremely high tech that goes extremely fast, but costs so much that it's commercially infeasible. Infeasible even for governments, when the most rudimentary benefit-cost analysis doesn't pencil. All the perks of MagLev--the reduced maintenance costs, the higher speeds--are offset by the cost of construction. If I offer a car that costs 20% less in maintenance, and goes 20% faster, but costs twice as much, it's obviously a mad decision. Better to buy two cars. I can't imagine things are any better today, when electric motors and wind turbines spiked the price of all the expensive magnetic compounds necessary to construct such a MagLev.
Worse yet, when the real advantage of the MagLev only comes at the highest speeds. In speedometer terms, the MagLev is only better than rail when you are traveling at 80 mph. All the other speeds, it's no better.
For trains, what holds down the speed is rarely the power of the train: It's typically the curve of the track. A train track is as flat as possible, with the lowest possible grade, as that requires the least amount of power, and is the most energy efficient. When faced with a trade-off between a curve up- and-down, and a curve side-to-side, every train ever goes with the latter. And the curve of the track (measured in the radius of the curve at it's lowest point) is what affects train speed.If you've ever run a model train, the surest way to derail is to take it around the curve too fast. One car goes, and it pulls the rest of the cars off the track. So when trains go around curves, they go very slowly. And for freight, this rarely matters--grain is in no rush to get anywhere. So small, tight curves are fine.
So, for a MagLev to make sense, it would need a very straight track. Just just freight-train straight and level. As an example, CAHSR suggests (Table 3.1.1) the following minima (for comparison):
250 mph - 550'
200 mph - 440'
175 mph - 385'
150 mph - 335'
125 mph - 275'
Higher speeds demand longer curves, and hence straighter alignments. If a MagLev is going to run at higher speeds (where it competes with HSR) then it requires much straighter alignments than HSR. And much straighter alignments cost more--more bridges, more gaps cut into hills. More buildings demolished. The price of a MagLev's advantages aren't in the MagLev, they are in the cost of the alignment to really let a MagLev fly.
So building a MagLev is like owning a car that only drives well at 80 mph--unless you've got lots of roads that let you drive 80 mph, don't bother. And it's that chicken-and-the-egg relationship that drives engineers (and railfans) mad. They know if you just had both, you'd be better off. But that's the architects delusion: That you can build everything at once. The reality is that building major infrastructure takes a lot of time, and that because of that scale, it's a stop-and-go process characterized by incremental investment. Urban planners get it. Rail planners get it. Crayonistas, not so much.
Someone commented elsewhere the MagLev is the Concorde of passenger trains: something extremely high tech that goes extremely fast, but costs so much that it's commercially infeasible. Infeasible even for governments, when the most rudimentary benefit-cost analysis doesn't pencil. All the perks of MagLev--the reduced maintenance costs, the higher speeds--are offset by the cost of construction. If I offer a car that costs 20% less in maintenance, and goes 20% faster, but costs twice as much, it's obviously a mad decision. Better to buy two cars. I can't imagine things are any better today, when electric motors and wind turbines spiked the price of all the expensive magnetic compounds necessary to construct such a MagLev.
Worse yet, when the real advantage of the MagLev only comes at the highest speeds. In speedometer terms, the MagLev is only better than rail when you are traveling at 80 mph. All the other speeds, it's no better.
For trains, what holds down the speed is rarely the power of the train: It's typically the curve of the track. A train track is as flat as possible, with the lowest possible grade, as that requires the least amount of power, and is the most energy efficient. When faced with a trade-off between a curve up- and-down, and a curve side-to-side, every train ever goes with the latter. And the curve of the track (measured in the radius of the curve at it's lowest point) is what affects train speed.If you've ever run a model train, the surest way to derail is to take it around the curve too fast. One car goes, and it pulls the rest of the cars off the track. So when trains go around curves, they go very slowly. And for freight, this rarely matters--grain is in no rush to get anywhere. So small, tight curves are fine.
So, for a MagLev to make sense, it would need a very straight track. Just just freight-train straight and level. As an example, CAHSR suggests (Table 3.1.1) the following minima (for comparison):
250 mph - 550'
200 mph - 440'
175 mph - 385'
150 mph - 335'
125 mph - 275'
Higher speeds demand longer curves, and hence straighter alignments. If a MagLev is going to run at higher speeds (where it competes with HSR) then it requires much straighter alignments than HSR. And much straighter alignments cost more--more bridges, more gaps cut into hills. More buildings demolished. The price of a MagLev's advantages aren't in the MagLev, they are in the cost of the alignment to really let a MagLev fly.
So building a MagLev is like owning a car that only drives well at 80 mph--unless you've got lots of roads that let you drive 80 mph, don't bother. And it's that chicken-and-the-egg relationship that drives engineers (and railfans) mad. They know if you just had both, you'd be better off. But that's the architects delusion: That you can build everything at once. The reality is that building major infrastructure takes a lot of time, and that because of that scale, it's a stop-and-go process characterized by incremental investment. Urban planners get it. Rail planners get it. Crayonistas, not so much.
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