Weird to me that they aren't accelerating till the midpoint and then breaking till the destination at a constant 1g. Gets around the space sickness by providing artificial gravity and should take ~hours rather than ~days.
Just for a bit of fun perspective, that’s 7 km/s faster than reentry velocity! Even if you felt like dealing with the heat, it would cost an ungodly amount of energy which kind of defeats the point of an elevator. On the other hand, you could ignore radiation shielding if the trip is short enough? Not worth the trade off I think.
Not sure if this would work, but how about using a wire with evenly-spaced metal beads, then using a magnet (a large one like used in MRI machines) to pull up the cart? You'll probably have to turn the magnet on/off at a specific frequency, depending on the momentum of the cart, which could be a challenge.
If you want constant acceleration, you need to maintain constant force. A higher-velocity vehicle applies that force across a greater distance per unit time, and therefore requires more power.
Accelerating 1 metric ton at 1g requires 9800 N. So at peak velocity (18 km/s), that's 180 megawatts per ton, which is more than 700 times the power to mass ratio of a Tesla P100D.
Surely friction is an issue at much faster speeds? I guess the fastest trains go 400+ KPH, with the fastest being maglev. I assume, though can't tell from the article, that the space elevator has physical contact with the cable, and I can't think of how one could reproduce maglev tech when going vertically.
So, there's surely a safe speed limit built into the materials being used? It's probably faster than the speed they're starting out with, but I kinda assume it can't be fast enough to shorten the trip to hours from days.
As an aside, moving people is probably not the most profitable use of the thing for the foreseeable future, as cool as that sounds. Getting a satellite into orbit for a tenth the cost is revolutionary (though they mention the cost compared to the shuttle, which is much more expensive than rocket transport...so they may be cherry-picking numbers to make this seem more revolutionary than it is).
Anyway, I can't think of how they could accelerate much beyond the fastest non-maglev train speeds without tearing apart the cable and car, but I may be underestimating the strength of carbon nanotubes, and whatever other component materials they're using. Perhaps there's a materials nerd here who knows.
Because it would require you to reach an improbably high velocity (especially for pulling yourself up a cable)--and you'd do so relatively quickly using an improbably large amount of energy in the process.
