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Hyperloop One Technology Tested Successfully In Nevada Desert
Dave Knott quotes a report from CBC.ca: Hyperloop One (formerly known as Hyperloop Technologies) conducted a successful test of its high speed transportation technology Wednesday in the desert outside Las Vegas. The seconds-long, outdoor demonstration featured what appeared to be a blip of metal gliding across a small track before disappearing into a cloud against the desert landscape. A fully operational hyperloop would whisk passengers and cargo in pods through a low pressure tube at speeds of up to 1,207 kph (750 mph). Maglev technology would levitate the pods to reduce friction in the city-to-city system, which would be fully autonomous and electric powered. A day earlier, the company had announced the closing of $80 million in financing and said it plans to conduct a full system test before the end of the year.
So ideally for a freight rail system we want high throughput, short delivery times, cheap, and running to/from convenient nearby locations.
Breaking this down further, it suggests we want
* Small trains (lowers latency - less time to wait for a train going to your destination. Removes/reduces need for transferring cargo between trains by allowing point-to-point service, so long as the 'point's are train stations.)
* Autonomous (required by 'small trains' and 'cheap')
* Handles congestion well (for high throughput with lots of small trains)
* Fast
* Moderately priced infrastructure.
* High density of train stations around the country
I.e. something like an internet for shipping containers.
Hyperloop gives us 'fast', but fails on infrastructure price, fails at least initially on density of stations, and congestion may be problematic. Starting with the existing rail network and moving to more automation and smaller trains and solving some congestion problems (perhaps the hardest bit) gives everything but 'fast', but for many purposes is 'fast enough'.
It still needs to be competitive compared to autonomous trucks.
TL;DR: I agree.
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Maglev is becoming a viable technology for long distance rail. The low pressure tunnel allows for more efficient low drag travel, perhaps even supersonic travel. How do you propose that the train "float" on a cushion of air in a low pressure environment? What form of propulsion are you proposing that is going to work in this low pressure environment, assuming you have a solution for the "floating" problem that doesn't involve maglev?
I couldn't believe how crude their contraption is. Everything they did is 20+ years old. There are theme park rides a hell of a lot more advanced than that thing and they will brake automatically and carry passengers.
Why aren't they concentrating on a 1/10 scale proof of concept that will be a hell of a lot cheaper to make and can advance the technology?
This is already partially solved in a way similar to passenger jets, which have to deal with a similar problem. You need enough oxygen for each passenger to last long enough until the problem can be addressed. For a passenger jet, that means 12-15 minutes while the pilot dives to low altitude. For a low pressure tunnel emergency that means slowing the train down and then letting normal air pressure into the tunnel in a controlled fashion. As far as air resistance is concerned, I think you are thinking about lower speeds than are planned for a hyperloop solution. Hyperloop designs are considering speeds that approach or possibly exceed mach 1. Drag goes up exponentially (velocity squared), so the air density becomes a much greater issue at those speeds. Besides drag, you also have to take into account the heating of the train due to drag.
That sounds like a solution looking for a problem. My uncle and grandfather work(ed) for the railroad. For freight, you're never going to make a dent with this plan. Freight is all about momentum, not speed. Starting and stopping cargo are the hardest parts. You need a powerful engine just to move 1 fully loaded car, but that same engine can pull lots of cars -- it just hast to pick up speed over time. You're never going to pick up serious speed before you get to a populated area where you have to slow down -- because railways cross roadways. Stopping even a single car quickly requires a bag of sand to be dropped on the steel railing and makes enough friction to ruin the wheels. You're not going to get cars carrying tons of cargo to go faster than the current system. Worse -- breaking up a single locomotive train w/ tens of cars into lots of smaller cars means lots and lots of wasteful engines that have to pull those smaller cars. They'd also have to have a much larger space between each car to be able to reasonably slow down in time should one have a problem. You'd need to increase the number of tracks to make up for the wasted space to push the same amount of cargo over time. In short, there's reasons why they do things the way they do them now... mostly physics and logistics reasons.
Assuming you could update the patchwork of decades old systems properly, it wouldn't give you much savings as humans will likely be required for safety reasons well into the future - just like pilots still fly passenger planes even though autopilot does most of the work between take-offs and landings... even subway trains have conductors. We're talking about miles of track that cross public roadways with children on bikes -- not going to go fully automatic anytime soon.
Even if you re-designed the entire system to be above-ground mag-lev freight with novel breaking systems to achieve this insane acceleration/deceleration, you'd have such massive construction and power issues, it would be super-expensive. The average weight for a freight rail car is around 130 tons fully loaded. A fully loaded passenger maglev car is between 50 and 70 tons. It's not impossible... and one could often just split the cargo between multiple cars if needed. It'd be expensive, though. You'd still need to use trucks to get from the train station to the final destination.
The hyperloop is for extremely fast passenger travel to replace airlines. It has lightweight cargo (people and maybe luggage), and can be built on railways above ground with cheaper construction than the support needed for heavy freight. Above-ground tubing can be safe enough to be an automated system. It's horribly expensive because of the land purchase, construction, maintenance, safety, etc... but, once it's built, it could offer transportation faster and safer than air travel. Should eventually be cheaper, too -- and no need to worry about hijackers as it's on a track... and there's no explosive fuel to blow up a building with even if it went off-track.
Basically, the hyperloop is the replacement for air travel over land. It could also carry cargo/freight in addition to passengers if the weight and space constraints allow. A hyperloop or maglev train system might solve other problems with the freight industry as well.