Elon Musk and the Hyperloop(jacquesmattheij.com)
jacquesmattheij.com
Elon Musk and the Hyperloop
http://jacquesmattheij.com/elon-musk-and-the-hyperloop
41 comments
Pressuring a system (depending on the pressure) would be more stress
and risk than a vacuum. Depending on materials used (concrete for
instance - that prefers to be loaded in compression), the vacuum can
actually IMPROVE stability and safety. As far as a pressurized "loop"
as you describe, it would greatly INCREASE DRAG compared to a vehicle
in the open air. What you describe is a 'Pneumatic Tube Transport'
(PTT) system (as used in bank drive-up windows). PTT does not scale
up well due to the enormous drag of air on the ENTIRE inside surface
of the tube. Large PTT systems take a lot of power regardless of use.
The energy per vehicle would be greater (but could be reduced a
little by using hydrogen or helium that has less drag than air (mostly
nitrogen)); however small molecules leak much more than large ones,
and the expensive working fluid would have to be replaced.
Google "Evacuated Tube Transport" (ETT) or "Evacuated Tube Transport Technologies" (ET3) (trade marks of ET3 Global Alliance, and et3.com Inc.) on google and youtube -- watch the videos to learn of more advantages. Read the first US patent (5,595,543) to learn exactly how all of what Musk claims (and much more) can be accomplished. NOTE: ET3 (tm) is the product of over 200 experts, companies, and institutions in 18 countries. We hope musk joins our efforts to implement ET3. ET3 is optimized to accommodate BOTH cargo and passengers in car sized vehicles. Initial (local) routes will be at 300-400mph, and ET3 will accomplish over 50 times more transportation (ton-miles and passenger-miles) per KWh than the most efficient electric car or train. ET3 cost is less than a tenth as much as HSR (high speed rail), mostly due to much less vehicle mass It takes 1/30th as much concrete and steel to support 1200lb car sized capsules (400lb vehicles that haul the same 800lb payload as a typical automobile) than to support 100 ton locomotives on elevated structure. ET3 has over 10 times more capacity than HSR at 350mph design speed, and 0ver 100 times more at 4000mph. Refs: search “ doi: 10.3969/j.issn.2095-087X.2011.01.007 “ for a peer reviewed paper published in Journal of Modern Transportation; US patent 5,595,543 (many additional patents in the ET3 portfolio)
Google "Evacuated Tube Transport" (ETT) or "Evacuated Tube Transport Technologies" (ET3) (trade marks of ET3 Global Alliance, and et3.com Inc.) on google and youtube -- watch the videos to learn of more advantages. Read the first US patent (5,595,543) to learn exactly how all of what Musk claims (and much more) can be accomplished. NOTE: ET3 (tm) is the product of over 200 experts, companies, and institutions in 18 countries. We hope musk joins our efforts to implement ET3. ET3 is optimized to accommodate BOTH cargo and passengers in car sized vehicles. Initial (local) routes will be at 300-400mph, and ET3 will accomplish over 50 times more transportation (ton-miles and passenger-miles) per KWh than the most efficient electric car or train. ET3 cost is less than a tenth as much as HSR (high speed rail), mostly due to much less vehicle mass It takes 1/30th as much concrete and steel to support 1200lb car sized capsules (400lb vehicles that haul the same 800lb payload as a typical automobile) than to support 100 ton locomotives on elevated structure. ET3 has over 10 times more capacity than HSR at 350mph design speed, and 0ver 100 times more at 4000mph. Refs: search “ doi: 10.3969/j.issn.2095-087X.2011.01.007 “ for a peer reviewed paper published in Journal of Modern Transportation; US patent 5,595,543 (many additional patents in the ET3 portfolio)
Usually when comparing speeds of trains and airplanes you factor in the transit time from city center to airport + security checks etc. So the time measured is total travel time. Railway stations are already at city center, and security is less strict so time savings are considerable for the benefit of rail.
Great points! The lateral g load could be reduced by banking the capsule - but you still raise an important limit that even with banking would still cause an unreasonable curve radius.
Launch loops are interesting. They seem to be even more difficult than tether-based space elevators, which have themselves been unable to work due to material strength:weight constraints on the tether. I'd expect the belt supporting a launch loop to have similar constraints, and the dynamic bending of the belt would raise fatigue concerns.
Agree with your speed estimations and that supersonic or near- speeds have very high drag costs and complicated analysis.
Launch loops are interesting. They seem to be even more difficult than tether-based space elevators, which have themselves been unable to work due to material strength:weight constraints on the tether. I'd expect the belt supporting a launch loop to have similar constraints, and the dynamic bending of the belt would raise fatigue concerns.
Agree with your speed estimations and that supersonic or near- speeds have very high drag costs and complicated analysis.
>I'd expect the belt supporting a launch loop to have similar constraints [as space elevators], and the dynamic bending of the belt would raise fatigue concerns.
The reason inertial schemes like the space fountain and the launch loop were created is to overcome those material limitations. Aside from the scale, the engineering and material science of a launch loop is relatively straight forward.
The seminal paper, which discusses rotor fatigue and much more: http://launchloop.com/LaunchLoop%3Faction=AttachFile%26do=ge...
The reason inertial schemes like the space fountain and the launch loop were created is to overcome those material limitations. Aside from the scale, the engineering and material science of a launch loop is relatively straight forward.
The seminal paper, which discusses rotor fatigue and much more: http://launchloop.com/LaunchLoop%3Faction=AttachFile%26do=ge...
I did a quick read and a search and didnt find any discussion of ribbon fatigue. The issue is that the various stressings on the ribbon thermal, bending, tension, and curving through the 28 km loop over many cycles. In general the mechanical analysis of ribbon strength was unconvincing to me.
One of the interesting things about Jacques speculation is that if you move the pressurized air with the capsules they never go super sonic, the air is moving with them and their motion relative to that air is pretty constrained. The duct friction issue however is a serious issue.
It could be a giant hack of course, it could be Elon saying he knows how to do it when he doesn't and getting all these great ideas to pour out. Or he could die and it would be his 'last company' legacy like Fermat's last theorem, sort of "Wow, really elegant way to do that, won't quite fit in the margin here though."
It could be a giant hack of course, it could be Elon saying he knows how to do it when he doesn't and getting all these great ideas to pour out. Or he could die and it would be his 'last company' legacy like Fermat's last theorem, sort of "Wow, really elegant way to do that, won't quite fit in the margin here though."
In aerodynamics, everything is relative. If you, plus a bunch of air are moving at supersonic speeds through a pipe, then that looks exactly the same as if you're moving a pipe at supersonic speeds over static you.
I think what Chuck meant was that the speed of sound increases with pressure, so the pressure wave in front of the capsule would cause the transition speed to supersonic to be higher. I'm not sure this is a good thing though from a drag perspective, but could be if it keeps the flow under ~0.8 Mach. Definately the complexity of the fluid dynamics at high speeds can't be neglected. http://en.wikipedia.org/wiki/Drag_(physics)#Wave_drag_in_tra...
The principal of "choked flow" limits flow velocity in a constant section tube to Mach one unless the pressure drop is much higher than 1 atm. The drag force at choked flow would be about 20 tons. Tests show drag in a tunnel with high blockage ratios can be more than an order of magnitude greater than the same shape moving in open air.
You're both right, at the boundary layer between the volume of air you're pushing and the tunnel there is going to be a bit of turbulence given the viscosity of the air, within the bubble you may never exceed the mach number for the air around you. Excellent paper put out by Barrett on designing long range sniper rifles [1] talking about the issues have having the bullet not be deflected by leaving the barrel (where even though its travelling quite fast it has yet to exceed the mach number of the expanding gas around it) and the ambient atmosphere (where the air is 'still' to the now speeding bullet). Needless to say the paper lost me in the fluid dynamics of the barrel air mixing with the outer air but they seemed pretty clear that inside the barrel things were pretty linear up to that point.
Anyway, what ever it turns out to be I'm sure it will be cool.
[1] My Dad is an engraver with an FFL and gets all sorts of interesting things in the mail. Usually to engrave, but the promotional literature is cool too.
Anyway, what ever it turns out to be I'm sure it will be cool.
[1] My Dad is an engraver with an FFL and gets all sorts of interesting things in the mail. Usually to engrave, but the promotional literature is cool too.
“Cheaper than high speed rail” - why is high speed rail expensive? I believe because precision contact between rail and wheel is required. How would this be done cheaper in a tunnel?
One issue with a tunnel is that even if the air and carriages are moving at the same speed, there is still drag or friction between the air and the wall of the tunnel by Poissiulle's law. At the proposed speeds (~300km/h) and distances (600km), this becomes a lot, and higher pressures (if my quick calculations are right) lead to higher energy requirements through higher air density.
In a vacuum, this friction would not exist. I can post my calcs if there is interest - I used a Moody chart and Darcy's friction equation, and ended up with an energy requirement that there would have to be ~80 million carriages going each way to be as efficient as a Telsa roadster, and neglecting any other losses.
One issue with a tunnel is that even if the air and carriages are moving at the same speed, there is still drag or friction between the air and the wall of the tunnel by Poissiulle's law. At the proposed speeds (~300km/h) and distances (600km), this becomes a lot, and higher pressures (if my quick calculations are right) lead to higher energy requirements through higher air density.
In a vacuum, this friction would not exist. I can post my calcs if there is interest - I used a Moody chart and Darcy's friction equation, and ended up with an energy requirement that there would have to be ~80 million carriages going each way to be as efficient as a Telsa roadster, and neglecting any other losses.
600 kilometers / 80 million carriages gives me 7.5 mm per carriage length so I think there is a bit of a problem with that calculation.
The limiting case is when the whole tube is full of carriages, say they're 4 meters long that would mean there are a maximum of 150,000 carriages in that 600 Km long tube at absolute maximum capacity, something that you probably should not want to get close to.
More realistically, a regular roadway has a spacing of about 30 meters per vehicle at 60 Mph, you might be able to pack them in that tight in a tube like this but that's still pretty tight and leaves very little room for error when shifting carriages in and out of the loop.
At that spacing you could stuff (600,000 / 34) = 17650 carriages in (none of those assembled into impromptu trains, which of course would increase the density).
If we assume train like assemblies of 10 cars with 30 meter spacing you'd be looking at a 40 meter train + spacing is 70 meters, or 8500 trains, so 85000 carriages.
Those would then be pushing a column of of air 30 meters long ahead of them.
The limiting case is when the whole tube is full of carriages, say they're 4 meters long that would mean there are a maximum of 150,000 carriages in that 600 Km long tube at absolute maximum capacity, something that you probably should not want to get close to.
More realistically, a regular roadway has a spacing of about 30 meters per vehicle at 60 Mph, you might be able to pack them in that tight in a tube like this but that's still pretty tight and leaves very little room for error when shifting carriages in and out of the loop.
At that spacing you could stuff (600,000 / 34) = 17650 carriages in (none of those assembled into impromptu trains, which of course would increase the density).
If we assume train like assemblies of 10 cars with 30 meter spacing you'd be looking at a 40 meter train + spacing is 70 meters, or 8500 trains, so 85000 carriages.
Those would then be pushing a column of of air 30 meters long ahead of them.
I was trying to compare the energy required to overcome friction of the air against the tunnel to driving the route conventionally. 80 million is an excessive number to expect want to travel at one time, which implies that driving is much more efficient from an energy required perspective.
Yes, I got that, but the fact that there isn't room in there for that many carriages means that the friction can't be that high. Unless there is a way in which the friction in a tube is so high that the little bit of air surrounding the vehicle would exert that much drag on the tunnel wall (so one vehicle length + say a few mm distance to the tunnel wall).
I'm not sure what the figure should be but this seems very high.
I'm not sure what the figure should be but this seems very high.
When fluids flow, there is a `no slip` condition at surfaces - that is the velocity of fluid at a surface is the same as the surface`s velocity. So in a stationary tunnel, the fluid may be moving at an average of 300 meters per second, but will be stationary at the wall. This makes a shear stress in the fluid and is what causes drag. In fact, making the air gap between the carraige and wall smaller will increase this drag since there is less distance for this transition to happen between stopped and fully moving air.
Consider if each carriage is pulling 30m of air a long distance at great speed. Consider if instead of the air moving against a stationary tunnel, a 30 meter section of tunnel was moving at the same distance and speed through stationary air. The drag on this would be high, much higher than a car at highway speeds.
Consider if each carriage is pulling 30m of air a long distance at great speed. Consider if instead of the air moving against a stationary tunnel, a 30 meter section of tunnel was moving at the same distance and speed through stationary air. The drag on this would be high, much higher than a car at highway speeds.
What if it isn't air, but an actual fluid, e.g. water? It cannot be compressed, so it's "crash proof" (carriages cannot hit other carriages with water in between). It also has plenty of mass, so once it has started moving, it will push carriages around easily. A torus with permanently moving water (probably a more high-tech fluid), where carriages are injected / removed after acceleration / before deceleration?
Both liquids and gasses are fluids and drag is worse in water than air, so the energy required would only be higher. Consider: is it harder to push your hand through the air or a tub of water?
> Consider: is it harder to push your hand through the air or a tub of water?
Consider a tub of water moving at the desired speed...
Consider a tub of water moving at the desired speed...
You'd still have the friction between carriage and wall.
[deleted]
What if we fill the whole tube with carriages, without any space between them and very little space between the carriage wall and the tunnel wall? That would leave much less room for turbulence and perhaps reduce friction.
If that works, you could then have "station" sections where you could place/remove "inner" carriages to/from the carriages running inside the loop and thus you'd never have to disconnect the main carriage loop.
If that works, you could then have "station" sections where you could place/remove "inner" carriages to/from the carriages running inside the loop and thus you'd never have to disconnect the main carriage loop.
Rail is also expensive because it needs track the entire length of the trip. Huge problems on the west coast right now running rail where it is wanted because you need the land...
One thing not mentioned here is speed. Musk has said this could go from LA to San Francisco in 30 minutes, which is an average speed of ~700 mph - slightly faster than a commercial airliner but in the same ballpark. I'm definitely not an expert in fluid dynamics, but it seems like safely maintaining that speed in a tube at atmospheric pressure would be difficult. Maybe there's some way to design the shape of the pods such that there's a very stable equilibrium keeping it away from the walls. Or you could potentially use a magnetic field to do this (similar to a tokamak) but that seems be trickier and more expensive than a mag-lev rail.
An evacuated tube has the advantage of being much more stable at high speeds and avoids the issue of excess heat from repeatedly compressing and expanding the air in the tube.
In any case, great read. I almost wonder if Musk has thrown this idea out half-baked just to get more people to start thinking outside the box about transportation...
An evacuated tube has the advantage of being much more stable at high speeds and avoids the issue of excess heat from repeatedly compressing and expanding the air in the tube.
In any case, great read. I almost wonder if Musk has thrown this idea out half-baked just to get more people to start thinking outside the box about transportation...
> Or you could potentially use a magnetic field to do this (similar to a tokamak) but that seems be trickier and more expensive than a mag-lev rail.
Using Halbach arrays would do it, without any active control.
Using Halbach arrays would do it, without any active control.
I think everyone is ignoring the elephant in the room.
This is a long story, but I'll try to keep it very short. Anyone interested contact me off-list for far more details and an unfinished paper with some of my research.
A couple of years ago my son and I were watching a documentary on the subject of concrete. It was very interesting. They covered a wide range of topics but one of them really started to trigger my curiosity: The Panama Canal.
I don't know why, but I became very interested in the financial metrics surrounding the canal. How much does it cost to cross it? How long does it take? How many ships cross it per year? Where do they come from? Where do they go?
The more I learned the more the reality of the Canal horrified me. Why?
The bulk of the commercial traffic through the Canal are container ships. And these ships burn something very nasty: Bunker Fuel. This is, by almost any measure, the dirtiest fuel you could burn. it's horrible stuff.
When I started to do the math I started to realize the magnitude of the problem. These ships move at about 20 miles per hour. They could go faster but there's a balance between the high cost of hydrodynamic drag and fuel costs. A trip from Shanghai to Long Beach takes about 18 days and will burn somewhere in the range of 3,600 to 7,200 metric tons of fuel. For those not comfortable visualizing units in the metric system, that's from 7,936,560 to 15,873,120 pounds. Yes, fifteen million pounds of the nastiest crap you could burn is used to bring your iPhones (conjecture) and other stuff from Shanghai to Long Beach.
If my research is correct, the fleet of about 100,000 cargo ships (Yes, 100,000!!!) burns over a million metric tons of bunker fuel PER DAY.
400 million metric tons of bunker fuel per year, which is equivalent to 120 billion gallons.
Can't relate to that number?
Here's an interesting comparison:
To get a better sense of how large this number is we can try to relate it to how many cars one could fill-up with fuel and for how long. 120 billion gallons would provide enough fuel to supply 100,000 cars (assuming a 20 gallon tank) with a full tank of gas every week...for over 1,000 years.
The evil, when it comes to pollution and energy dependence, isn't the much-abused light bulb; it's the elephant in the room: Ocean-going cargo ships.
While our mass media chooses to focus its attention on an oil spill (because it is sensational and it serves political purposes), what is really killing our planet slowly is the transportation of iPhones, Blackberries, TV's, blenders, washers, cars, widgets and gadgets on inefficient and highly-polluting ocean-going vessels. Even the latest Gulf spill is insignificant in terms of environmental impact when compared to what 100,000 ships are doing to our environment each and every year.
It is estimated that the fleet of nearly 100,000 cargo ships in the world produces over 20 million tons of Sulfur Oxides (SOx) per year. For comparison, the entire fleet of automobiles in the world (about 800 million cars) produces about 80,000 tons of the same contaminant.
How about the Canal?
A container ship traveling from Los Angeles to NYC through the Canal will burn about 4,500 metric tons of buker-C fuel. This amount of fuel costs approximately US $1.8 million. Canal fees would run somewhere around $300K. The trip from L.A. to NYC through the Canal runs well over two million dollars, without including handling, insurance, crew costs, amortization, maintenance, etc. That's quite a chunk of change, however, when divided by the thousands of containers a ship can move it becomes a few hundred dollars per container.
How many ships go through the Canal per year?
Approximately 15,000.
I'll leave you to do the math. I have far more detail in my notes. What these ships are doing to our environment is simply horrific. The pollution doesn't stop at the act of burning fuel.
Cargo ships are also the source of an unusual form of pollution. Ships use huge ballast tanks to stabilize themselves. These ballast tanks are filled and emptied of sea water during loading and unloading operations at port. It is through this mechanism that cargo ships are responsible for transporting harmful organisms across the world into ecosystems that cannot handle them. The introduction of non-native species into a new ecosystem can have devastating consequences.
And so, from watching a simple documentary I came to the realization that, for some strange reason, we have been ignoring the most significant source of environmental pollution on our planet. And, beyond that, one of the largest --if not the largest-- consumer of petroleum products.
I didn't stop at just identifying the problem. I also wanted to take a stab at a solution. I came up with something I called "The American High Speed Cargo System" (AHSCS) as a loose proposal. This would be a cargo-only, electric powered, high speed rail system. It would connect --at the very least-- both coasts and, ideally, other major US ports. The idea would be to move cargo over land from port to port at 200 miles per hour. High speed passenger trains in the US are a waste of money and that's particularly true in California (don't get me started there). Not so for high-speed cargo.
The numbers are there to support it: A cargo ship spends over two million dollars to get from L.A. to NYC. Probably closer to three. Those same containers could be moved far more efficiently over land, at similar or lower costs and pollute far, far less. You are exchanging aerodynamic drag for hydrodynamic drag. Huge difference.
In terms of energy costs (just the electricity), I came up with numbers in the order of $10K for a trip from L.A. to NYC. I further estimated that the system would require around 700MW of power, let's call it 1,000MW. We have 53 nuclear plants that can source 1GW each. This is a case where nuclear power might be a really good option.
However, the scope of the project needs to be realized. Developing and building such a systems has the potential to generate hundreds of thousands of jobs, if not millions. It should be revenue neutral if not positive (sorry Panama). It would allow for the installation of upgraded communications and power backbones that would be synergistic to the process of building the rail system. It would also allow for the potential to install huge solar and wind-power farms to fully or partially power the system.
I have not explored every angle but would like to think that, if my numbers and assumptions are right, this could be the most important project this nation could embark on. You have to think in terms of a hundred or two-hundred year scale. These ships are not going to go away unless something very significant changes. Of course, the same concept ought to be replicated across the planet. Again, if I am right, we should strive to eliminate most, if not all, container ships traversing our oceans. We are making an absolute mess out of our planet.
http://news.discovery.com/tech/shipping-network-map.html
Like I said, there's more. If interested email me off list and I can send you a copy of my notes so far. It'd be interesting to have someone go over my notes and verify my assumptions and calculations. I tried to raise the issue with politicians but, what can I say, I only have so much time to deal with morons.
NOTE:
I thank you for your comments. I have to ask that you do me a favor. Please refrain from making categorical statements about the relative efficiency of ships vs. a proposed high-speed electric train without having done the math yourself. Please drop me an email and I'll be more than happy to provide you with a copy of my calcs, an unfinished paper as well as links, PDF's and references. Then we can talk about the merits of the concept. I am actually very interested in having the concept, calculations and assumptions criticized. Arguing outside of a common frame of reference is rather difficult.
This is a long story, but I'll try to keep it very short. Anyone interested contact me off-list for far more details and an unfinished paper with some of my research.
A couple of years ago my son and I were watching a documentary on the subject of concrete. It was very interesting. They covered a wide range of topics but one of them really started to trigger my curiosity: The Panama Canal.
I don't know why, but I became very interested in the financial metrics surrounding the canal. How much does it cost to cross it? How long does it take? How many ships cross it per year? Where do they come from? Where do they go?
The more I learned the more the reality of the Canal horrified me. Why?
The bulk of the commercial traffic through the Canal are container ships. And these ships burn something very nasty: Bunker Fuel. This is, by almost any measure, the dirtiest fuel you could burn. it's horrible stuff.
When I started to do the math I started to realize the magnitude of the problem. These ships move at about 20 miles per hour. They could go faster but there's a balance between the high cost of hydrodynamic drag and fuel costs. A trip from Shanghai to Long Beach takes about 18 days and will burn somewhere in the range of 3,600 to 7,200 metric tons of fuel. For those not comfortable visualizing units in the metric system, that's from 7,936,560 to 15,873,120 pounds. Yes, fifteen million pounds of the nastiest crap you could burn is used to bring your iPhones (conjecture) and other stuff from Shanghai to Long Beach.
If my research is correct, the fleet of about 100,000 cargo ships (Yes, 100,000!!!) burns over a million metric tons of bunker fuel PER DAY.
400 million metric tons of bunker fuel per year, which is equivalent to 120 billion gallons.
Can't relate to that number?
Here's an interesting comparison:
To get a better sense of how large this number is we can try to relate it to how many cars one could fill-up with fuel and for how long. 120 billion gallons would provide enough fuel to supply 100,000 cars (assuming a 20 gallon tank) with a full tank of gas every week...for over 1,000 years.
100,000 cars.
20 gallons per week.
For a THOUSAND years.
The evil, when it comes to pollution and energy dependence, isn't the much-abused light bulb; it's the elephant in the room: Ocean-going cargo ships.
While our mass media chooses to focus its attention on an oil spill (because it is sensational and it serves political purposes), what is really killing our planet slowly is the transportation of iPhones, Blackberries, TV's, blenders, washers, cars, widgets and gadgets on inefficient and highly-polluting ocean-going vessels. Even the latest Gulf spill is insignificant in terms of environmental impact when compared to what 100,000 ships are doing to our environment each and every year.
It is estimated that the fleet of nearly 100,000 cargo ships in the world produces over 20 million tons of Sulfur Oxides (SOx) per year. For comparison, the entire fleet of automobiles in the world (about 800 million cars) produces about 80,000 tons of the same contaminant.
How about the Canal?
A container ship traveling from Los Angeles to NYC through the Canal will burn about 4,500 metric tons of buker-C fuel. This amount of fuel costs approximately US $1.8 million. Canal fees would run somewhere around $300K. The trip from L.A. to NYC through the Canal runs well over two million dollars, without including handling, insurance, crew costs, amortization, maintenance, etc. That's quite a chunk of change, however, when divided by the thousands of containers a ship can move it becomes a few hundred dollars per container.
How many ships go through the Canal per year?
Approximately 15,000.
I'll leave you to do the math. I have far more detail in my notes. What these ships are doing to our environment is simply horrific. The pollution doesn't stop at the act of burning fuel.
Cargo ships are also the source of an unusual form of pollution. Ships use huge ballast tanks to stabilize themselves. These ballast tanks are filled and emptied of sea water during loading and unloading operations at port. It is through this mechanism that cargo ships are responsible for transporting harmful organisms across the world into ecosystems that cannot handle them. The introduction of non-native species into a new ecosystem can have devastating consequences.
And so, from watching a simple documentary I came to the realization that, for some strange reason, we have been ignoring the most significant source of environmental pollution on our planet. And, beyond that, one of the largest --if not the largest-- consumer of petroleum products.
I didn't stop at just identifying the problem. I also wanted to take a stab at a solution. I came up with something I called "The American High Speed Cargo System" (AHSCS) as a loose proposal. This would be a cargo-only, electric powered, high speed rail system. It would connect --at the very least-- both coasts and, ideally, other major US ports. The idea would be to move cargo over land from port to port at 200 miles per hour. High speed passenger trains in the US are a waste of money and that's particularly true in California (don't get me started there). Not so for high-speed cargo.
The numbers are there to support it: A cargo ship spends over two million dollars to get from L.A. to NYC. Probably closer to three. Those same containers could be moved far more efficiently over land, at similar or lower costs and pollute far, far less. You are exchanging aerodynamic drag for hydrodynamic drag. Huge difference.
In terms of energy costs (just the electricity), I came up with numbers in the order of $10K for a trip from L.A. to NYC. I further estimated that the system would require around 700MW of power, let's call it 1,000MW. We have 53 nuclear plants that can source 1GW each. This is a case where nuclear power might be a really good option.
However, the scope of the project needs to be realized. Developing and building such a systems has the potential to generate hundreds of thousands of jobs, if not millions. It should be revenue neutral if not positive (sorry Panama). It would allow for the installation of upgraded communications and power backbones that would be synergistic to the process of building the rail system. It would also allow for the potential to install huge solar and wind-power farms to fully or partially power the system.
I have not explored every angle but would like to think that, if my numbers and assumptions are right, this could be the most important project this nation could embark on. You have to think in terms of a hundred or two-hundred year scale. These ships are not going to go away unless something very significant changes. Of course, the same concept ought to be replicated across the planet. Again, if I am right, we should strive to eliminate most, if not all, container ships traversing our oceans. We are making an absolute mess out of our planet.
http://news.discovery.com/tech/shipping-network-map.html
Like I said, there's more. If interested email me off list and I can send you a copy of my notes so far. It'd be interesting to have someone go over my notes and verify my assumptions and calculations. I tried to raise the issue with politicians but, what can I say, I only have so much time to deal with morons.
NOTE:
I thank you for your comments. I have to ask that you do me a favor. Please refrain from making categorical statements about the relative efficiency of ships vs. a proposed high-speed electric train without having done the math yourself. Please drop me an email and I'll be more than happy to provide you with a copy of my calcs, an unfinished paper as well as links, PDF's and references. Then we can talk about the merits of the concept. I am actually very interested in having the concept, calculations and assumptions criticized. Arguing outside of a common frame of reference is rather difficult.
Have you checked your calculations against David MacKay's? His conclusion was that "International shipping is a surprisingly efficient user of fossil fuels; so getting road transport off fossil fuels is a higher priority than getting ships off fossil fuels."
http://www.inference.phy.cam.ac.uk/withouthotair/c15/page_95...
http://www.inference.phy.cam.ac.uk/withouthotair/c20/page_13...
http://www.inference.phy.cam.ac.uk/withouthotair/c15/page_95...
http://www.inference.phy.cam.ac.uk/withouthotair/c20/page_13...
I think it's simple physics. Moving anything on water at any speed is far more expensive than moving the equivalent thing on land. It is, at the simplest level, a comparison of hydrodynamic drag vs aerodynamic drag. It can't possibly be more efficient to displace water for days and days rather than push air out of the way, even at high speed.
You can pull a 10 tonne yacht with one hand on a rope. Try pulling a 10 tonne truck...
Also according to the US Transportation Energy Book, waterbourne transport more than a order of magnitude more efficient than road freight, and about 50% more efficient than rail.
http://en.wikipedia.org/wiki/Fuel_efficiency_in_transportati...
Also according to the US Transportation Energy Book, waterbourne transport more than a order of magnitude more efficient than road freight, and about 50% more efficient than rail.
http://en.wikipedia.org/wiki/Fuel_efficiency_in_transportati...
On your first point, I refer you to Google and Wikipedia for excellent articles on basic physics. In particular look to understand the relationship of power as it relates to speed.
On the second point. Our cargo rail system is crap. Nowhere in my write-up am I proposing that we unload 100,000 cargo ships per year and load these containers onto diesel trucks or the current train system. That would be incredibly dumb, inefficient, more harmful to the environment and, well, actually impossible.
No, the idea is that a new highly-efficient, all-electric, highly-automated and cargo-only transportation system be built with the express purpose of moving container-based cargo from coast to coast (and port to port) at the highest possible speed and lowest possible power consumption. The idea further suggests that the required energy can come from nuclear, wind and solar power.
The complete elimination of the burning of the most harmful form of fossil fuel from the transportation system is one of the stated goals of the idea.
Furthermore, the idea is also to look 50, 100 or even 200 years into the future. Pollution aside, fossil fuel cost is absolutely, positively guaranteed to increase over the next 200 years. The current system of burning millions of tons of bunker-c fuel per year to bring widgets to Walmart isn't a viable and scalable long-term solution. Not to mention the fact that it is royally fucking up the environment at many levels. I am not a crazy environmentalist by any measure, but this is stupid.
On the second point. Our cargo rail system is crap. Nowhere in my write-up am I proposing that we unload 100,000 cargo ships per year and load these containers onto diesel trucks or the current train system. That would be incredibly dumb, inefficient, more harmful to the environment and, well, actually impossible.
No, the idea is that a new highly-efficient, all-electric, highly-automated and cargo-only transportation system be built with the express purpose of moving container-based cargo from coast to coast (and port to port) at the highest possible speed and lowest possible power consumption. The idea further suggests that the required energy can come from nuclear, wind and solar power.
The complete elimination of the burning of the most harmful form of fossil fuel from the transportation system is one of the stated goals of the idea.
Furthermore, the idea is also to look 50, 100 or even 200 years into the future. Pollution aside, fossil fuel cost is absolutely, positively guaranteed to increase over the next 200 years. The current system of burning millions of tons of bunker-c fuel per year to bring widgets to Walmart isn't a viable and scalable long-term solution. Not to mention the fact that it is royally fucking up the environment at many levels. I am not a crazy environmentalist by any measure, but this is stupid.
"On the second point. Our cargo rail system is crap. Nowhere in my write-up am I proposing that we unload 100,000 cargo ships per year and load these containers onto diesel trucks or the current train system. That would be incredibly dumb, inefficient, more harmful to the environment and, well, actually impossible."
The US freight rail system is the best in the world.[1] We move 10x more than Europe most years on a tons times distance basis. The running gear may look antiquated, but the fundamental numbers are staggering.
"No, the idea is that a new highly-efficient, all-electric, highly-automated and cargo-only transportation system be built with the express purpose of moving container-based cargo from coast to coast (and port to port) at the highest possible speed and lowest possible power consumption."
There is very little demand for raising the speed of freight rail in the US. Speed generally compounds inefficiencies.
Freight handling is by and large already automated and container based in the US rail network.
Existing electric designs preclude the use of double stacked container flat cars, one of the keys of US freight efficiency. Perhaps you have an innovation here?
Building an entirely new high speed electric rail network for freight is an absurd idea. I don't think you've even begun to model the economic realities, particularly the capex of building a new rail network radius'd and graded for high speed, with all above grade crossings.
[1]: http://www.economist.com/node/16636101
The US freight rail system is the best in the world.[1] We move 10x more than Europe most years on a tons times distance basis. The running gear may look antiquated, but the fundamental numbers are staggering.
"No, the idea is that a new highly-efficient, all-electric, highly-automated and cargo-only transportation system be built with the express purpose of moving container-based cargo from coast to coast (and port to port) at the highest possible speed and lowest possible power consumption."
There is very little demand for raising the speed of freight rail in the US. Speed generally compounds inefficiencies.
Freight handling is by and large already automated and container based in the US rail network.
Existing electric designs preclude the use of double stacked container flat cars, one of the keys of US freight efficiency. Perhaps you have an innovation here?
Building an entirely new high speed electric rail network for freight is an absurd idea. I don't think you've even begun to model the economic realities, particularly the capex of building a new rail network radius'd and graded for high speed, with all above grade crossings.
[1]: http://www.economist.com/node/16636101
I read that article with interest. Of course our rail system is not crap when compared to others. That's not what I meant.
What I meant is that it could be much, much better. The article you point out hints at some of the issues: The inter-mingling of passenger and cargo trains ends-up seriously affecting the potential performance of cargo trains.
With regards to it being an absurd idea. Well, of course it is! And so is the case for nearly every idea that sparked a revolution in technology and thinking. The earth NOT at the center of the universe? Absurd! The earth not flat? Absurd? Everyone needs a computer on their desk? Absurd!
Not that I am comparing this to any of those shifts in technology. What I am trying to point out is that being open minded enough to even consider the seemingly absurd is an important part of discovering new ideas and developing new technologies. I always consider the absurd. I have hundreds of ideas catalog that are probably absurd. The alternative is to discount everything as ridiculous without even giving it an honest look. I just don't do that.
For example: Could this high speed train take the form of an underground tunnel connecting both coasts? This is absolutely ridiculous and probably even insane to consider. However, I take the approach of at least doing the research to try to get a sense of proportion in terms of cost and technical feasibility. For example, would there be an important mining element to the project that could offset the costs? I don't know and I am not trying to argue for a 3,000 mile tunnel. All I am saying is that I believe that it is very important to give seemingly ridiculous ideas a chance to be explored and, if need be, discarded based on data and not knee-jerk reaction.
What I meant is that it could be much, much better. The article you point out hints at some of the issues: The inter-mingling of passenger and cargo trains ends-up seriously affecting the potential performance of cargo trains.
With regards to it being an absurd idea. Well, of course it is! And so is the case for nearly every idea that sparked a revolution in technology and thinking. The earth NOT at the center of the universe? Absurd! The earth not flat? Absurd? Everyone needs a computer on their desk? Absurd!
Not that I am comparing this to any of those shifts in technology. What I am trying to point out is that being open minded enough to even consider the seemingly absurd is an important part of discovering new ideas and developing new technologies. I always consider the absurd. I have hundreds of ideas catalog that are probably absurd. The alternative is to discount everything as ridiculous without even giving it an honest look. I just don't do that.
For example: Could this high speed train take the form of an underground tunnel connecting both coasts? This is absolutely ridiculous and probably even insane to consider. However, I take the approach of at least doing the research to try to get a sense of proportion in terms of cost and technical feasibility. For example, would there be an important mining element to the project that could offset the costs? I don't know and I am not trying to argue for a 3,000 mile tunnel. All I am saying is that I believe that it is very important to give seemingly ridiculous ideas a chance to be explored and, if need be, discarded based on data and not knee-jerk reaction.
[deleted]
> You can pull a 10 tonne yacht with one hand on a rope. Try pulling a 10 tonne truck...
This probably deserves a little more attention.
Having done a lot of sailing as well as ocean-fishing on different size vessels I know exactly what you are talking about. What you might be confusing is that at zero speed there's a huge difference between something floating on water and a truck resting on the ground.
In the case of a large boat floating on water, so long as you are not after making it move quickly you are almost just fighting inertia. So, yes, a fifteen year old kid pulling on a rope could make a large boat move.
When it comes to a truck sitting on the ground you have to contend with rolling friction as well as the static friction (because nothing is moving) and the viscous drag of all the mechanical elements, oil and grease in the drivetrain. It could take hundreds of pounds of force to get it to budge. Once your break through static friction then you have a much reduced dynamic friction and viscous drag (oil and grease in the drivetrain) --again, so long as speed is very, very low-- as well as the rolling friction of the tires.
If, on the other hand, that truck was resting on a frozen lake bed and if the tires are not frozen-glued into the ice, and, if the ice is not deformed under the tires, the same fifteen year old kid could move it just as well as he moved the boat. In fact, it might even be easier because there isn't a significant v^3 component to the power required to make it move.
Once you start to add speed to the problem it is easy to see that moving the same object through water will require at least 830 times more water.
At speed the power required to counter drag comes into play.
If it takes one horsepower to move something in air at a given speed you'll need over 800 horsepower to achieve the same speed in water. It's the difference between a model airplane engine and a Formula 1 race car engine.
There's a good article in Wikepedia on drag:
http://en.wikipedia.org/wiki/Drag_(physics)
Get down to the "Power" heading. That's the formula you want to look at.
To get back to your yacht vs. truck example. What you would really have to experience is pulling each of them at 20 or 30 miles per hour with a rope (chain?). Of course, it would take super-human strength and endurance to be able to do that.
This probably deserves a little more attention.
Having done a lot of sailing as well as ocean-fishing on different size vessels I know exactly what you are talking about. What you might be confusing is that at zero speed there's a huge difference between something floating on water and a truck resting on the ground.
In the case of a large boat floating on water, so long as you are not after making it move quickly you are almost just fighting inertia. So, yes, a fifteen year old kid pulling on a rope could make a large boat move.
When it comes to a truck sitting on the ground you have to contend with rolling friction as well as the static friction (because nothing is moving) and the viscous drag of all the mechanical elements, oil and grease in the drivetrain. It could take hundreds of pounds of force to get it to budge. Once your break through static friction then you have a much reduced dynamic friction and viscous drag (oil and grease in the drivetrain) --again, so long as speed is very, very low-- as well as the rolling friction of the tires.
If, on the other hand, that truck was resting on a frozen lake bed and if the tires are not frozen-glued into the ice, and, if the ice is not deformed under the tires, the same fifteen year old kid could move it just as well as he moved the boat. In fact, it might even be easier because there isn't a significant v^3 component to the power required to make it move.
Once you start to add speed to the problem it is easy to see that moving the same object through water will require at least 830 times more water.
At speed the power required to counter drag comes into play.
Power = 1/2 * fluid density * velocity ^3 * coefficient of drag * area
If it takes one horsepower to move something in air at a given speed you'll need over 800 horsepower to achieve the same speed in water. It's the difference between a model airplane engine and a Formula 1 race car engine.
There's a good article in Wikepedia on drag:
http://en.wikipedia.org/wiki/Drag_(physics)
Get down to the "Power" heading. That's the formula you want to look at.
To get back to your yacht vs. truck example. What you would really have to experience is pulling each of them at 20 or 30 miles per hour with a rope (chain?). Of course, it would take super-human strength and endurance to be able to do that.
But container ships move so much stuff at a time that they're vastly more efficient than, say, big rig trucks. I'll bet they even give rail a run for its money.
Big rig trucks isn't any part of my proposal. Conventional rail in the US is horribly crippled. Shoot me an email and you can look at my data. Then we can have a discussion. I am very interested in having a discussion from a common frame of reference.
Then why not write a blog article about it or something. I don't see why such discussion should happen "off list", because it would in fact restrict the discussion to one-on-one's between you and whoever emails you, without anyone benefiting from the extra eyes.
I can understand his position. I would guess he wants to refine the idea privately a bit before presenting it to a larger more public audience.
Comparing hydrodynamics and aerodynamics here is not quite comparing apples to apples: I expect much less surface area is exposed to water on a ship than exposed to air on a train, and speed are lower. Drag scales with velocity squared. A calculation is required, and would also have to account for the weight of cargo each is carrying.
Sure it is. Without air or water the cost of shipping would be almost nil.
POWER to overcome drag is proportional to the CUBE of the velocity. This is the main reason container ships have been slowing down from about 30 miles per hour to 20 in direct response to the cost of fuel.
The power to overcome drag is also directly proportional to the density of the fluid.
Here's a practical example: Let's move a Toyota Camry through air and water at 20 miles per hour and compare. We'll ignore friction.
http://www.toyota.com/camry/specs.html
How about now moving up to 40 miles per hour?
If we moved the Toyota Camry through air at 188 miles per hour we would need nearly exactly the same power required to move the same car through water at 20 miles per hour.
Bottom line, moving anything on water is very expensive if you have to burn fuel to do it. Unless I am missing something very fundamental there simply is no comparison.
POWER to overcome drag is proportional to the CUBE of the velocity. This is the main reason container ships have been slowing down from about 30 miles per hour to 20 in direct response to the cost of fuel.
The power to overcome drag is also directly proportional to the density of the fluid.
Air density: 1.2041 kg/m^3
Water density: 1,000.00 kg/m^3 (pure water)
Here's a practical example: Let's move a Toyota Camry through air and water at 20 miles per hour and compare. We'll ignore friction.
http://www.toyota.com/camry/specs.html
Frontal area: 57.9in x 71.7in = 2.68 m^2
Coefficient of drag: 0.28
Power = 1/2 * density * velocity ^ 3 * area * coefficient of drag
Power in air =
1/2 * 1.2041 Kg/m^3 * (8.9 m/s ^ 3) * 2.68 m^2 * 0.28
= 0.43 horsepower
Power in water =
1/2 * 1,000 Kg/m^3 * (8.9 m/s ^ 3) * 2.68 m^2 * 0.28
= 353.02 horsepower
How about now moving up to 40 miles per hour?
Power in air = 3.4 HP
Power in water = 2,824.14
If we moved the Toyota Camry through air at 188 miles per hour we would need nearly exactly the same power required to move the same car through water at 20 miles per hour.
Bottom line, moving anything on water is very expensive if you have to burn fuel to do it. Unless I am missing something very fundamental there simply is no comparison.
This is just not right.
Unless it's a submarine, a ship doesn't move through water, it floats on top of it. The wetted surface is going to be a tiny fraction of the total frontal area. 90% or more of the hydrodynamic drag of a ship (by area) is in the air, not in the water.
For example, here is a nice little 21-foot 1200-lb motor boat that can reach 16 knots with a 25 hp motor, while carrying four people: http://www.southportislandmarine.com/ordereze/1011/page.aspx
Unless it's a submarine, a ship doesn't move through water, it floats on top of it. The wetted surface is going to be a tiny fraction of the total frontal area. 90% or more of the hydrodynamic drag of a ship (by area) is in the air, not in the water.
For example, here is a nice little 21-foot 1200-lb motor boat that can reach 16 knots with a 25 hp motor, while carrying four people: http://www.southportislandmarine.com/ordereze/1011/page.aspx
No, the calculations are exactly right given the conditions I presented.
The nice little boat you are linking to can do what it does largely because at a certain speed it will start to plane. These are very, very different conditions.
Two of the components of drag on a boat are form and parasitic or frictional drag. The first can be thought of as simply the drag created to push water out of the way. Here the shape of the boat is important. The second is the drag created by water "rubbing" against the portion of the hull in contact with it. Think of sandpaper against wood. More wood and more sandpaper means more resistance to motion.
As speed increases both friction and form drag increase with the square of the speed.
On a planing hull --one that can generate lift and get the boat up and partially out of the water-- form drag decreases significantly once you are "on a plane" (off the water) and friction drag increases. As it turns out, each boat has a sweet spot where it operates best. And, of course, as you get on a plane the power required in order to reach or sustain a given speed decreases significantly when compared to a displacement (non-planing) hull.
A Panamax ship carrying 4,400 TEU does not plane. It is, as far as a know, a pure displacement vessel. So, yeah, you need a tremendous amount of power to counteract significant components of both form and parasitic drag.
A Panamax container ship can have up to nearly 400 square meters of cross-sectional area under water. That's about 4,000 square feet. So, while it isn't exactly the same thing, only for the purpose of visualization, imagine a 100 foot long x 40 foot rigid piece of plywood fully submerged in water. Not try to push it forward at 20 miles per hour. Right. That's why they have to burn nearly a million and a half dollars of bunker-C fuel to get from Los Angeles to NYC.
Physics can be really inconvenient sometimes.
The nice little boat you are linking to can do what it does largely because at a certain speed it will start to plane. These are very, very different conditions.
Two of the components of drag on a boat are form and parasitic or frictional drag. The first can be thought of as simply the drag created to push water out of the way. Here the shape of the boat is important. The second is the drag created by water "rubbing" against the portion of the hull in contact with it. Think of sandpaper against wood. More wood and more sandpaper means more resistance to motion.
As speed increases both friction and form drag increase with the square of the speed.
On a planing hull --one that can generate lift and get the boat up and partially out of the water-- form drag decreases significantly once you are "on a plane" (off the water) and friction drag increases. As it turns out, each boat has a sweet spot where it operates best. And, of course, as you get on a plane the power required in order to reach or sustain a given speed decreases significantly when compared to a displacement (non-planing) hull.
A Panamax ship carrying 4,400 TEU does not plane. It is, as far as a know, a pure displacement vessel. So, yeah, you need a tremendous amount of power to counteract significant components of both form and parasitic drag.
A Panamax container ship can have up to nearly 400 square meters of cross-sectional area under water. That's about 4,000 square feet. So, while it isn't exactly the same thing, only for the purpose of visualization, imagine a 100 foot long x 40 foot rigid piece of plywood fully submerged in water. Not try to push it forward at 20 miles per hour. Right. That's why they have to burn nearly a million and a half dollars of bunker-C fuel to get from Los Angeles to NYC.
Physics can be really inconvenient sometimes.
My "apples to apples" point is that density is not the only parameter to change when comparing ships to trains.
1. Assuming the same speeds. Ships go slower than trains (say 40kmph compared to 80kmph). 2. The frontal area is not the same as only part of the ship is underwater. Further, for a long train, the frontal area drag is likely less than the skin friction drag. 3. The coefficient of drag is not the same as the CD of a train is different than for a boat. 4. The amount of cargo on each is not the same, and would need to be normalized for a fair comparison.
I'd be happy to take a quick look at your materials off-line, please send to jd2planks at hotmail
1. Assuming the same speeds. Ships go slower than trains (say 40kmph compared to 80kmph). 2. The frontal area is not the same as only part of the ship is underwater. Further, for a long train, the frontal area drag is likely less than the skin friction drag. 3. The coefficient of drag is not the same as the CD of a train is different than for a boat. 4. The amount of cargo on each is not the same, and would need to be normalized for a fair comparison.
I'd be happy to take a quick look at your materials off-line, please send to jd2planks at hotmail
I really don't see it as even close. Moving anything through air requires far less power than moving the same thing through water.
With regards to the rest of your comments, I've done some of those calculations. Again, there is no comparison.
I need to repeat that the idea here is NOT to in ANY WAY use existing truck or cargo rail systems. They just don't perform. Here in the US you are lucky if you can get cargo trains moving on average at 20 to 30 miles per hour. In other words, the move just as slowly as cargo ships, except that they can't pull the same number of containers.
The idea is that a new purpose-built system is the solution.
Also, please keep in mind that the idea here isn't necessarily to search for the most efficient mode of cargo transportation in complete isolation of the realities of where they derive their energy from.
Here's a very interesting paper on the aerodynamics of high-speed trains:
http://ompldr.org/vMXlsOA/Aerodynamics_HSR02.pdf
Anyhow, I sent you all my files via a shared Dropbox folder. I'd be interested in what you have to say once you have a chance to look at it all.
To be sure, there are huge issues with the idea that have absolutely nothing whatsoever to do with science and technology. I could not imagine the problems one might encounter in terms of the various special-interest groups that would get in the way of building such a thing, even if it was so good that it would save the world. I think the phrase "can't get out of our own way to save our lives" rings true in more than one way, at least in the US.
With regards to the rest of your comments, I've done some of those calculations. Again, there is no comparison.
I need to repeat that the idea here is NOT to in ANY WAY use existing truck or cargo rail systems. They just don't perform. Here in the US you are lucky if you can get cargo trains moving on average at 20 to 30 miles per hour. In other words, the move just as slowly as cargo ships, except that they can't pull the same number of containers.
The idea is that a new purpose-built system is the solution.
Also, please keep in mind that the idea here isn't necessarily to search for the most efficient mode of cargo transportation in complete isolation of the realities of where they derive their energy from.
Here's a very interesting paper on the aerodynamics of high-speed trains:
http://ompldr.org/vMXlsOA/Aerodynamics_HSR02.pdf
Anyhow, I sent you all my files via a shared Dropbox folder. I'd be interested in what you have to say once you have a chance to look at it all.
To be sure, there are huge issues with the idea that have absolutely nothing whatsoever to do with science and technology. I could not imagine the problems one might encounter in terms of the various special-interest groups that would get in the way of building such a thing, even if it was so good that it would save the world. I think the phrase "can't get out of our own way to save our lives" rings true in more than one way, at least in the US.
I think the problem is that you're imagining the same frontal area moving through two fluids. Certainly moving the same toyota camry through air and water will give vastly different results, but if you turned that toyota camry upside down and sealed all the holes, the actual wetted area that needed to be pushed through the water would be significantly less.
I'd be happy to look at your calculations. My knowledge of hydrodynamics is somewhat limited, but I do have a fairly good understanding of aerodynamics and a lot of that stuff is transferable. I can't decipher your email riddle though - is [4:5] saying the 4th and 5th characters? Mine is leorampen (at) gmail.
I'd be happy to look at your calculations. My knowledge of hydrodynamics is somewhat limited, but I do have a fairly good understanding of aerodynamics and a lot of that stuff is transferable. I can't decipher your email riddle though - is [4:5] saying the 4th and 5th characters? Mine is leorampen (at) gmail.
Sorry, that's a little Verilog. [4:9] means indeces [4][5][6][7][8][9], in other words, "martin".
The camry example was just an illustration of the power relationship of something moving through water. Nothing more than that.
The comparison of a container ship with 5,000 TEU (2,500 40 foot containers) vs. a train is, of course, different. And, of course, it isn't as simple as looking at cross-sectional area. That would be a gross oversimplification. Sometimes you have to assume that a cow is a uniform sphere of milk just to start to have some numbers to talk about.
Imagine a train design to carry containers at 200 miles per hour. Single file. So, now, the cross sectional area is that of a single container, which is very small. If the train is designed to minimize parasitic drag and all of the frictional components of the rolling system it could be incredibly efficient when compared to a ship pushing some 4000 square feet (400 square meters) of cross sectional area of water at 20 miles per hour.
And, as I have said multiple times, this isn't really solely about pure energy efficiency as much as a forward looking idea to that hopes to deal with the grotesque level of environmental pollution these ships produce as well as what might happen over the next 100 or 200 years with fossil fuels. One really has to start looking in at least a 50 to 100 year time scale to understand that what we are doing today is not sustainable in any way at all. To some extent, arguing the finer points of how much one displaces vs. the other and whether one solution is a few percent more efficient than the other is to miss the point.
I'll go ahead and send you a link to the data.
The camry example was just an illustration of the power relationship of something moving through water. Nothing more than that.
The comparison of a container ship with 5,000 TEU (2,500 40 foot containers) vs. a train is, of course, different. And, of course, it isn't as simple as looking at cross-sectional area. That would be a gross oversimplification. Sometimes you have to assume that a cow is a uniform sphere of milk just to start to have some numbers to talk about.
Imagine a train design to carry containers at 200 miles per hour. Single file. So, now, the cross sectional area is that of a single container, which is very small. If the train is designed to minimize parasitic drag and all of the frictional components of the rolling system it could be incredibly efficient when compared to a ship pushing some 4000 square feet (400 square meters) of cross sectional area of water at 20 miles per hour.
And, as I have said multiple times, this isn't really solely about pure energy efficiency as much as a forward looking idea to that hopes to deal with the grotesque level of environmental pollution these ships produce as well as what might happen over the next 100 or 200 years with fossil fuels. One really has to start looking in at least a 50 to 100 year time scale to understand that what we are doing today is not sustainable in any way at all. To some extent, arguing the finer points of how much one displaces vs. the other and whether one solution is a few percent more efficient than the other is to miss the point.
I'll go ahead and send you a link to the data.
If we had trains or planes as large as the tankers and container ships, you would probably be right. The thing is that drag is areal, freight is volumetric. Drag goes up as the square of the dimension, freight capacity as the cube. This allows large ships to be much more efficient than trucks or trains.
Power to overcome form drag goes up with the cube of the velocity and linearly with fluid density. Moving something through water requires over 800 times more power than in air.
The only thing that could make land-based transport less efficient (other than fuel and power-plant issues) is rolling and drivetrain losses. I doubt that those make-up for the over 800-to-1 power discrepancy.
The greater point here isn't a pissing match between individual efficiencies but rather to look at the problem with a long (50 to 200 years) perspective in terms of pollution, fossil fuel consumption, geo-political and economic concerns and more.
The only thing that could make land-based transport less efficient (other than fuel and power-plant issues) is rolling and drivetrain losses. I doubt that those make-up for the over 800-to-1 power discrepancy.
The greater point here isn't a pissing match between individual efficiencies but rather to look at the problem with a long (50 to 200 years) perspective in terms of pollution, fossil fuel consumption, geo-political and economic concerns and more.
The drag of ships moving at less than hull speed (non planing) is a function of: skin friction (shearing of the boundary layer), wave making, and Reynolds number (related to the length of the ship, and the viscosity of the fluid).
One interesting article says that one of the mega container ships pollutes more than 50 million cars see:
http://www.guardian.co.uk/environment/2009/apr/09/shipping-p...
The claim is that just 15 of the worlds biggest ships pollute more than all cars in the world combined.
One interesting article says that one of the mega container ships pollutes more than 50 million cars see:
http://www.guardian.co.uk/environment/2009/apr/09/shipping-p...
The claim is that just 15 of the worlds biggest ships pollute more than all cars in the world combined.
Yup. This is exactly what I was driving at when I said that everyone is ignoring the elephant in the room. You can clean-up automobile emissions all you want. You can even stop flying all the jetliners in the world. Still, by far, the largest source of pollution in transportation are container ships. What they are doing to our planet both above and in water (species pollution) is horrible.
How is it economically efficient to move non-time-sensitive cargo at high speeds? If the goal is to avoid the pollution associated with sea shipping, the natural competitor is the existing land-based freight network: trucks and diesel trains. If you want to sanity-check your numbers, that's the number to compare it to.
Here's a back-of-the-envelope calculation for moving a 40-foot shipping container over rail from NYC to LA: 3 cents per ton-mile * 30 tons * 2800 miles = ~$2500. I couldn't find a quote for that route by sea, but from NYC to London I got a $1750 quote, and I imagine the costs are comparable.
I believe you that container ships are huge polluters. It sounds, though, that it'd be easier to fix this by taxing those externalities, rather than making two arguments simultaneously: that container ships are bad and that we should build a giant high-speed domestic freight rail network.
Take the numbers above with a huge grain of salt, but here are my sources for them: 3 cents per ton-mile: http://www.kehoe.org/owen/portfolio/truck_vs_rail.pdf a 40' container weighs 29kg loaded: http://hamburg-sud.com/hsdg/en/hsdg/servicesproducts/contain...
Here's a back-of-the-envelope calculation for moving a 40-foot shipping container over rail from NYC to LA: 3 cents per ton-mile * 30 tons * 2800 miles = ~$2500. I couldn't find a quote for that route by sea, but from NYC to London I got a $1750 quote, and I imagine the costs are comparable.
I believe you that container ships are huge polluters. It sounds, though, that it'd be easier to fix this by taxing those externalities, rather than making two arguments simultaneously: that container ships are bad and that we should build a giant high-speed domestic freight rail network.
Take the numbers above with a huge grain of salt, but here are my sources for them: 3 cents per ton-mile: http://www.kehoe.org/owen/portfolio/truck_vs_rail.pdf a 40' container weighs 29kg loaded: http://hamburg-sud.com/hsdg/en/hsdg/servicesproducts/contain...
I invite you to play with the numbers yourself. Drop me a line.
One Panamax size ship moves 4,400 TEU (container units). Larger ships can do up to 15,000 TEU. If you even tried to move that many containers using conventional trucks or diesel trains you'd probably create more pollution than the ships, not to mention the overloading of the roads and rail.
One of the reasons for AHSCS having to be a high-speed system is that you need to bring speed into the equation in order to deal with the sheer magnitude of the cargo moving about.
The other reason is that you need to be able to offer something competitive in order for shipping companies to choose to go over land with AHSCS versus through the Canal.
The third reason is both economic and geopolitical in nature. By traversing the American continent quickly (~3,000 miles in a day) the system would become competitive for cargo that goes from, say, Shanghai to London/Europe through the Suez Canal.
If, again, my numbers are correct, it would be cheaper and less risky to send Europe-bound cargo from Shanghai to the US West Coast for transportation across the continent using AHSCS and then by ship to Europe. You'd be able to get the cargo there in about the same time or faster, at a lower cost and with far less pollution because you'd eliminate days of bunker-C burning transportation from the process.
In the process you'd also significantly modify the economics of the petroleum economy in the Arab world and isolate the rest of the world from the perils and political issues surrounding the Suez Canal.
As I said in my note. If something like this makes sense from an ecological and business perspective there ramifications go far, far deeper than the simple idea of moving containers by land on an electric high-speed train. It could be a game changer for the next couple of hundred years.
One Panamax size ship moves 4,400 TEU (container units). Larger ships can do up to 15,000 TEU. If you even tried to move that many containers using conventional trucks or diesel trains you'd probably create more pollution than the ships, not to mention the overloading of the roads and rail.
One of the reasons for AHSCS having to be a high-speed system is that you need to bring speed into the equation in order to deal with the sheer magnitude of the cargo moving about.
The other reason is that you need to be able to offer something competitive in order for shipping companies to choose to go over land with AHSCS versus through the Canal.
The third reason is both economic and geopolitical in nature. By traversing the American continent quickly (~3,000 miles in a day) the system would become competitive for cargo that goes from, say, Shanghai to London/Europe through the Suez Canal.
If, again, my numbers are correct, it would be cheaper and less risky to send Europe-bound cargo from Shanghai to the US West Coast for transportation across the continent using AHSCS and then by ship to Europe. You'd be able to get the cargo there in about the same time or faster, at a lower cost and with far less pollution because you'd eliminate days of bunker-C burning transportation from the process.
In the process you'd also significantly modify the economics of the petroleum economy in the Arab world and isolate the rest of the world from the perils and political issues surrounding the Suez Canal.
As I said in my note. If something like this makes sense from an ecological and business perspective there ramifications go far, far deeper than the simple idea of moving containers by land on an electric high-speed train. It could be a game changer for the next couple of hundred years.
My understanding was that the Panama canal is mostly used for international shipping and that your NY -> LA use case would not be as common as East Asia -> Europe. Do you have the data to back this up?
Also note that the Panama Canal system is set to expand by 2015,
and that US East-coast ports are already expanding their
cargo capacity in expectation of more & bigger container
ships, routing Pacific->Panama->East rather than
Pacific->West->rail->East.
https://en.wikipedia.org/wiki/Panama_Canal#Third_set_of_lock...
http://www.siteselection.com/issues/2011/nov/eastern-seaboar...
https://en.wikipedia.org/wiki/Panama_Canal#Third_set_of_lock...
http://www.siteselection.com/issues/2011/nov/eastern-seaboar...
East Asia to Europe goes through the Suez Canal. There's plenty of data on what goes through the Panama canal. Shoot me and email and I'll hand you a copy of all of my data for you to study.
Old report, but seems to me that barge shipping is more energy efficient than truck or rail (see page x):
http://www.cbo.gov/sites/default/files/cbofiles/ftpdocs/53xx...
More recent report from Europe comparing different transport modes for CO2 by kg-km traveled. Shipping is reported as most efficient over rail and road. http://www.eea.europa.eu/data-and-maps/indicators/energy-eff...
More recent report from Europe comparing different transport modes for CO2 by kg-km traveled. Shipping is reported as most efficient over rail and road. http://www.eea.europa.eu/data-and-maps/indicators/energy-eff...
Note that I am not suggesting that conventional rail or trucking are options here. Trucking is only efficient for "last mile" delivery.
I would suggest to turn the discussion in a different direction -- why don't we bring back wind power to sea transport? There have been multiple trials with mega-kites that can demonstrate 20% or more fuel savings with relatively modest implementations. (see http://www.treehugger.com/cars/cargo-ship-with-kites-first-t... just one example).
Direct wind power would seem to beat out most of your proposal for land-based transport, which, even running on renewable energy, would require a double-conversion to electricity and then back to motive force. It certainly beats out nuclear!
Direct wind power would seem to beat out most of your proposal for land-based transport, which, even running on renewable energy, would require a double-conversion to electricity and then back to motive force. It certainly beats out nuclear!
The automated kite idea on cargo ships is very interesting isn't it. Yes, I saw that during my research. The problem is that you are still limited to where and when you have wind. It would have to be a hybrid.
Very interesting and thought provoking.
If you've not been, I highly recommend a trip to Panama City to checkout the canal - it's simply mind blowing watching a super tanker go through the locks.
Do you have any data on the number of container ships that move through the canal that are simply moving from one US coast to the other?
If you've not been, I highly recommend a trip to Panama City to checkout the canal - it's simply mind blowing watching a super tanker go through the locks.
Do you have any data on the number of container ships that move through the canal that are simply moving from one US coast to the other?
That trip is long and expensive for me, so these videos will have to do: http://www.youtube.com/results?search_query=panama+canal+sup...
There's a webcam, but it's not a live stream.
There's a webcam, but it's not a live stream.
I know there's a number someone in my research. I just don't recall it. I'd have to dig it up.
Keep in mind that there's a lot more than container ships that also move across the canal. Tankers being one example.
Keep in mind that there's a lot more than container ships that also move across the canal. Tankers being one example.
Re: "no rails" - perhaps it reduces friction by not touching the ground, via a combination of a railgun propulsion + airfoil. Thus, not needing continuous maglev for levitation. Also explains the "concord" comparison.
I'm thinking:
- Air based, but near the ground
- The vehicle is concord shaped
- Vehicle is launched into the air via rail gun (like a fighter jet on a ship: http://en.wikipedia.org/wiki/Electromagnetic_Aircraft_Launch...)
- Lots of boosting strips a few KMs apart.
- Based on the rail gun concept, the same "boosting" strip could also slow down or speed up a vehicle
- It removes the need for anything between the stations except open space.
- Minimal on-vehicle propulsion - otherwise I imagine the constant accelerate/decelerate would be a little unbearable for human flight
- Failure mode of the vehicle is to glide to a landing (though could magnetic eddy currents be used for breaking in a rail gun with minimal/no current?)
- The loop could refer to the idea of a continual loop of boosters, in opposite directions, removing the need for large "turn around" stations at either end
The Hyperloop reminds me a lot of the Swissmetro [1] project which was launched in 1974 and was intended to connect Swiss cities trough evacuated tunnels which would house maglev trains. The evacuation made the project very expensive but a lot of tests were run and a lot of the learning probably can be applied. Solving some of the problems that made the Swissmetro so expensive could lead to what the Hyperloop wants to be.
[1 ]http://en.wikipedia.org/wiki/Swissmetro (the German language article is much more extensive: http://de.wikipedia.org/wiki/Swissmetro)
[1 ]http://en.wikipedia.org/wiki/Swissmetro (the German language article is much more extensive: http://de.wikipedia.org/wiki/Swissmetro)
I'd like to add another possibility into the mix, I think it might be based on some moving walkway concepts that have been considered for quite a few years but have never caught on or progressed passed the prototype stage.
The idea is that rather than being a straight line with a sort of conveyor belt, the walkway is made of plates like an escalator, and the ends of the walkway curve off from the main body of it. This means that a user steps on to a slow moving plate, immediately goes around a corner on it, and in doing so accelerates to a much faster speed, with the opposite happening at the destination.
As soon as I heard the word 'Hyperloop', this is what I thought of. It's a looped system, but with an extra dimension in a way as different sections operate at different speeds. I think this could be scaled up to be perhaps a track system that 'cars' are put onto with passengers inside, but I don't know.
Is this a reasonable possibility? Maybe.
✓ Ground based
✓ Weather independent
✓ Like a railgun (if propelled with magnets)
✓ Is not a pressurised tube
✓ Leaves when you arrive
? Could hold solar panels
? Cheap
? Revolutionise the transport industry
✗ No rails - depends on your interpretation of this, one could argue that a pressurised tube is a kind of track or rail for a carriage.
The idea is that rather than being a straight line with a sort of conveyor belt, the walkway is made of plates like an escalator, and the ends of the walkway curve off from the main body of it. This means that a user steps on to a slow moving plate, immediately goes around a corner on it, and in doing so accelerates to a much faster speed, with the opposite happening at the destination.
As soon as I heard the word 'Hyperloop', this is what I thought of. It's a looped system, but with an extra dimension in a way as different sections operate at different speeds. I think this could be scaled up to be perhaps a track system that 'cars' are put onto with passengers inside, but I don't know.
Is this a reasonable possibility? Maybe.
✓ Ground based
✓ Weather independent
✓ Like a railgun (if propelled with magnets)
✓ Is not a pressurised tube
✓ Leaves when you arrive
? Could hold solar panels
? Cheap
? Revolutionise the transport industry
✗ No rails - depends on your interpretation of this, one could argue that a pressurised tube is a kind of track or rail for a carriage.
The starting point of the argument is kind of whacky: He claims that the sentence "It is not (an evacuated tunnel)." is somehow the same as "It is a (not evacuated) tunnel.", but he completely ignores the fact that the position of the article that he deliberately changes resolves this ambiguity! So, duh, if you change the sentence it means something different...
I agree the rearrangement of the word order is confusing, but I can also see that Musk could have been saying "it is not an evacuated tunnel". (In fact this is the default interpretation I would probably take...) Listening to the original quote could help us, but ultimately there's no way to know if he's talking about tunnels in general or just evacuated ones.
But your interpretation is much, much weaker than "a not evacuated tunnel".
If it's not a tunnel, it's still not an <i>evacuated</i> tunnel.
But if it's "a not evacuated tunnel", then it must be a tunnel.
Edit: Actually, I think with the article "an" between the "not" and the adjective, there is no way in English grammar to interpret the "not" to negate only the adjective instead of the whole adjective+noun "evacuated tunnel". Unfortunately I'm neither a native speaker, nor a linguist, so I cannot back it up with anything but feeling for the language and the fact that this is how I always see it used ;).
If it's not a tunnel, it's still not an <i>evacuated</i> tunnel.
But if it's "a not evacuated tunnel", then it must be a tunnel.
Edit: Actually, I think with the article "an" between the "not" and the adjective, there is no way in English grammar to interpret the "not" to negate only the adjective instead of the whole adjective+noun "evacuated tunnel". Unfortunately I'm neither a native speaker, nor a linguist, so I cannot back it up with anything but feeling for the language and the fact that this is how I always see it used ;).
> Edit: Actually, I think with the article "an" between the "not" and the adjective, there is no way in English grammar to interpret the "not" to negate only the adjective instead of the whole adjective+noun "evacuated tunnel".
Well, if you add another "only" before "interpret" then you'd be correct. Otherwise, it is open to interpretation either way.
Panel 11: http://www.giantitp.com/comics/oots0367.html
Well, if you add another "only" before "interpret" then you'd be correct. Otherwise, it is open to interpretation either way.
Panel 11: http://www.giantitp.com/comics/oots0367.html
!(evacuated && tunnel) == (!evacuated && tunnel)
Except the second parsing does not seem to be correct under English grammar...
I would propose that colloquial English is too imprecise to draw such a precise conclusion, so the better alternative is to express possible interpretations as propositions and see what works.
Didn't Elon also say that the Hyperloop would be buildable/achievable without having to obtain large swaths of contiguous land for the construction of the entire loop (which is next to impossible in developed countries)?
How does this prediction meet that requirement? Or am I missing something?
This is the quote I'm referring to:
"It also can’t have a right of way issue, where people have to give up their homes."
http://techcrunch.com/2012/11/19/elon-musk-with-jobs-gone-go...
How does this prediction meet that requirement? Or am I missing something?
This is the quote I'm referring to:
"It also can’t have a right of way issue, where people have to give up their homes."
http://techcrunch.com/2012/11/19/elon-musk-with-jobs-gone-go...
You are absolutely right, someone else in this thread also brought it up. I completely missed out on that requirement and indeed it seems to invalidate the whole thing.
Unless there is a recycling of roads somehow.
The thing that bugs me about the whole 'space' angle is that if that is the solution it is only usable between endpoints, and roads are usable for everybody (also those people living between the endpoints).
You then get the same issues that you have with airports, you have to actually go to one of very few terminals in order to get on the loop. And ground transportation converging on the loop would be the bottle-neck (think highway LA - SF with only one on-ramp).
So likely we're missing a huge piece of the puzzle still.
Unless there is a recycling of roads somehow.
The thing that bugs me about the whole 'space' angle is that if that is the solution it is only usable between endpoints, and roads are usable for everybody (also those people living between the endpoints).
You then get the same issues that you have with airports, you have to actually go to one of very few terminals in order to get on the loop. And ground transportation converging on the loop would be the bottle-neck (think highway LA - SF with only one on-ramp).
So likely we're missing a huge piece of the puzzle still.
Definitely. It's still enjoyable to read these ideas though =)
I think most of OP's arguments are spot on, but I think it's likely to be an elevated system installed over the center divider of the (mostly very straight and very flat) I-5 corridor. Tunneling that distance just isn't feasible at the stated cost.
(I expound at greater length here: http://franking.tumblr.com/post/36241325898/my-personal-spec...)
(I expound at greater length here: http://franking.tumblr.com/post/36241325898/my-personal-spec...)
Several comments mentioned freight transport below, but not in this context. The loop you've described requires some "density" of carriages to maintain the "group inertia". One obvious way to fill gaps that are too big is to put freight cars into the loop to fill them.
Very nice article.
Very nice article.
People have built systems called Atmospheric Railways that could be closed to Elon's vision than an evacuated tunnel.
http://en.wikipedia.org/wiki/Atmospheric_railway
http://en.wikipedia.org/wiki/Atmospheric_railway
I remember Musk saying that its propulsion source was similar to that of a rail gun's. Sorry, can't remember where, but it was recent.
He also recently said it's "a cross between a Concorde and a rail gun". That would at least enforce the maglev principle Jacques envisioned. It wouldn't be quite a Concorde in the pressurized tube though. But it's not impossibly far away from that concept, maybe Musk deliberately described it in a bit mysterious fashion. Time will tell.
> it leaves when you arrive
Its just maglev trains with some novel enclosed design with carriage dissociation?
A bit like this chinese train concept that has drop off/pick up of carriages:*
*http://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s...
Its just maglev trains with some novel enclosed design with carriage dissociation?
A bit like this chinese train concept that has drop off/pick up of carriages:*
*http://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s...
Maybe "Concorde" was just his way of saying it's fast and it transports people.
He also said that there aren't any rails and it runs on the ground. At the moment, we have a Concorde without wings[0] (a lifting body Concorde, perhaps?) crossed with a railgun without rails. Sounds like vaporware.
[0]: It could still have wings but operate under ground effect, though it seems that it would be difficult to keep your leading edge intact travelling just above a hard surface "twice as fast as an airliner". "Twice as fast as an airliner" is Mach 0.85 * 2 = Mach 1.7 at FL360, which translates into Mach 1.5 at sea level. One useful thing we learn from this is that this system will basically have to be propelled by compressed air or electromagnetic force, since props don't work over Mach 1 and we don't have electric turbines.
[0]: It could still have wings but operate under ground effect, though it seems that it would be difficult to keep your leading edge intact travelling just above a hard surface "twice as fast as an airliner". "Twice as fast as an airliner" is Mach 0.85 * 2 = Mach 1.7 at FL360, which translates into Mach 1.5 at sea level. One useful thing we learn from this is that this system will basically have to be propelled by compressed air or electromagnetic force, since props don't work over Mach 1 and we don't have electric turbines.
Hmm, well I guess roads are cheaper than rails (i.e. rails along the entire route of the trip, not speed up rails like in a rail gun). And powering something from fixed locations (guns) is cheaper than bringing your engine with you.
So maybe it is like a train, one person per, but it runs on cheap road like track, and it's propulsion is provided by fixed stations. If each track was a straight run from station to station you could just ditch the wheels and whatnot and fire the thing between stations along the ground.
There's no way it could move so fast and still use car roads, unfortunately, so it will still have problems buying track space or building tunnels or building elevated paths. Too bad it runs on the ground.
So maybe it is like a train, one person per, but it runs on cheap road like track, and it's propulsion is provided by fixed stations. If each track was a straight run from station to station you could just ditch the wheels and whatnot and fire the thing between stations along the ground.
There's no way it could move so fast and still use car roads, unfortunately, so it will still have problems buying track space or building tunnels or building elevated paths. Too bad it runs on the ground.
> Hmm, well I guess roads are cheaper than rails [...]
We could look that up. But considering that roads and rails the world over are often build by governments or government owned corporations, I expect Elon Musk to have found a much cheaper way to build his infrastructure.
We could look that up. But considering that roads and rails the world over are often build by governments or government owned corporations, I expect Elon Musk to have found a much cheaper way to build his infrastructure.
How much air pressure and track length would you need to accelerate a craft like this to supersonic speeds? ponders. Come to think of it, would that even be physically possible? My understanding of the "sonic boom" phenomenon is that it involves the craft breaking through a zone of high air pressure that has accumulated in front of it... Surely this wouldn't be possible if the pressure itself were propelling the craft. My (uninformed) guess would be that supersonic speeds are attainable with this kind of system, but probably unfeasible, and crafts probably wouldn't experience the sonic boom phenomenon.
"Rail gun" could illustrate the way carriages are added to and remove from the loop.
In the technical literature, the term "rail gun/railgun" is strongly associated with electromagnetic propulsion methods:
http://en.wikipedia.org/wiki/Railgun
http://en.wikipedia.org/wiki/Railgun
Ah, I was thinking of a Gatling gun (http://en.wikipedia.org/wiki/Rotary_cannon), not a rail gun. The concept of rotary tubes seemed to mesh with OP's vision.
Or a continuous maglev force (as the OP wrote) for the entire track, augmented with air pressure to store acceleration energy in the system for the other trains.
...the first bit of Hyperloop speculation that actually makes sense and seems plausible ...though the price will this will likely go up because it's new and untested technology and it has to be SAFE: the price difference between "doing something" and "doing something safely" can be orders of magnitude (think airplane safety) so I wouldn't rush to invest in it though...
As with SpaceX I think Musk would solve this by designing for humans but testing with cargo.
The good thing is, this kind of system can be well tested before entering the market, because it does not rely on human intervention. Meaning, you test exactly the conditions you will always have.
I'm aware this is not adding much to the discussion but I couldn't shift the intro to futurama out of my head while reading the post.
Interesting.. What if if gets shot one direction, presurizing something, which it uses to shoot back the other direction
waiting for passenger
SF [||| <> - - - - - - - - - - - - - - - ] LA
pressurized --> pretty spaced out "stuff"
SF [-| - |- |- |- <>-| - |- |- -| - |- |- ] LA
in transit..
SF [ - - - - - - - - - - - - - - - <> ||| ] LA
<- presurized for returnJust like everything else in life the system would be subject to the laws of thermodynamics. The act of pressurising air would heat it up, and heat loss would mean that it wouldn't be fully reversible.
I suspect that a fully evacuated system using magnetic propulsion and energy recovery would be more efficient - the turbulent nature of air and the low-quality nature of heat energy would probably work against you to make a pneumatic spring fairly inefficient.
I suspect that a fully evacuated system using magnetic propulsion and energy recovery would be more efficient - the turbulent nature of air and the low-quality nature of heat energy would probably work against you to make a pneumatic spring fairly inefficient.
I don't think there's much doubt that an evacuated tube would be very efficient. Not only that, but you could go much faster. Jacques has rejected that hypothesis for other reasons.
"Jacques has rejected that hypothesis for other reasons."
Specifically, due to a specific statement that it is not an evacuated tube.
Specifically, due to a specific statement that it is not an evacuated tube.
Well, yes, but he also supplied some arguments why his idea might be better which is what I was referring to.
sounds interesting,but this wont fit well with "it leaves when you arrive".
I always imagined Hyperloop as carriages pushed by a plasma armature, in a rail gun loop. just like a plasma-rail gun.
I always imagined Hyperloop as carriages pushed by a plasma armature, in a rail gun loop. just like a plasma-rail gun.
It's a "loop", so it won't be a single tube, but a torus ("donut"), probably stretched.
So it's what they have in Futurama?
http://goo.gl/uEmNW
I'm not really sure how it "can't crash", nor how there aren't any "rails" (or things that look suspiciously like rails).
I'm not really sure how it "can't crash", nor how there aren't any "rails" (or things that look suspiciously like rails).
You know they were planning on building this in Manhattan?
Another point to mention is that it is also solar-powered.
sorry for being kind of a buzz kill - but I'd rather see elon musk venture away from traditional engineering ventures and going into life sciences. the hyperloop seems like an interesting concept, but I don't really see where it fits in, given that his electrical revolution of individual transportation succeeds. Very densely populated areas like new york are already reasonably served by a metro - scaling that system might be cheaper and equally effective as the hyperloop described by jacques mattheij. building new tunnels is very expensive and would probably account for most of the costs in this endeavor. additionally finding spare space in dense cities to construct such a hyperloop might be very difficult besides existing sewer systems and electrical lines, offsetting the benefits of the hyperloop (after all this would require massive public funding)
expanding this system to long distances would be really interesting, however even more expensive, given the need to construct long tunnels or tubes.
expanding this system to long distances would be really interesting, however even more expensive, given the need to construct long tunnels or tubes.
Whatever the Hyperloop is, it's a long-distance transport mechanism, not a replacement for the subway -- he said so much himself: http://inhabitat.com/elon-musks-hyperloop-train-could-travel...
Techwise, I still think the Lofstrom loop theory sounds the most likely: http://en.wikipedia.org/wiki/Launch_loop
Techwise, I still think the Lofstrom loop theory sounds the most likely: http://en.wikipedia.org/wiki/Launch_loop
Musk has said that he doesn't want to be involved in Hyperloop, and after publishing it next month will just leave it up to others to build/test/commercialise/etc. I guess he doesn't have much time being two CEOs and a CTO.
I'm curious what your overall point is?
The purpose of new innovations is to improve something. It's possible that in the very short term something like wouldn't be the most cost effective thing, however it's not about the very short term, but rather about the potential. In most existing transportation systems, the potential of the system without large changes has probably mostly been realized. The potential of something like this may be much larger, which is why it would be worthwhile.
The purpose of new innovations is to improve something. It's possible that in the very short term something like wouldn't be the most cost effective thing, however it's not about the very short term, but rather about the potential. In most existing transportation systems, the potential of the system without large changes has probably mostly been realized. The potential of something like this may be much larger, which is why it would be worthwhile.
my overall point is that I would rather see musk devoting his time to more promising and (in my opinion) more valuable projects (which danpalmer just said he would)
Musk has also noted that the system would be "protected from the elements"... Perhaps he meant the 'pods' inside the tube would be protected.
Almost sounds like a bigger version of http://shweeb.com
[deleted](1)
I don't think the tunnel would need to be pressurised. If the air moved at the same speed as the train, no resistance would be met.
That's what I meant by using the carriages as the impellers, so effectively they push against the air in front of them up to the next carriage, which pulls on this air because it leaves a partial vacuum behind it. So there is no external source of pressure, it's just the carriages moving and 'drafting' in each others wake.
There will still be resistance though, both from the walls as well as leakage between the carriage and the walls (there can't be a really good seal there or the friction between the carriage and the wall would become too large, and since the wall is stationary and the carriage is moving very fast this friction is likely sizeable).
There will still be resistance though, both from the walls as well as leakage between the carriage and the walls (there can't be a really good seal there or the friction between the carriage and the wall would become too large, and since the wall is stationary and the carriage is moving very fast this friction is likely sizeable).
Do you know the speed differences that could occur in a tunnel system like this, versus an "open" on-ground maglev system?
However, somehow using pressurized tubes for mail failed in the long run. I find those very fascinating, and apparently once upon a time some big cities were actually connected with a lot of such pressure tubes for sending mail. But apparently they were too unreliable and ended up going into oblivion.
Would be interesting if some of them could be resurrected somehow.
Another idea for improving transport: with modern technology better routing should be possible. Instead of all people boarding the same train that stops at every station, why not only board a carriage that goes directly to your destination? That could save a lot of time, I think.
Would be interesting if some of them could be resurrected somehow.
Another idea for improving transport: with modern technology better routing should be possible. Instead of all people boarding the same train that stops at every station, why not only board a carriage that goes directly to your destination? That could save a lot of time, I think.
If I'm not mistaken, these systems are still in use in some major European cities, but only for government communication.
http://en.wikipedia.org/wiki/Pneumatic_tube
http://en.wikipedia.org/wiki/Pneumatic_tube
If you’re interested in pressurised tubs for mail, 99% Invisible had a recent show on it: http://99percentinvisible.org/post/31907362467/episode-61-a-...
I think your second idea is closer to what I think matches the things known about Hyperloop. I am convinced that electric (or hybrid) cars that self drive along beacons is the obvious next step in human urban transportation. These follow loops, like bus routes, that will pick you up when you get to a location along the loop since you have requested it (e.g. phone app) and drop you off at say a station, or another loop intersection where you can get into another loop vehicle, a loop bus or train at a scheduled and managed time. It can send the right size and amount of vehicles out of the depot into loop depending on how many people want to get on during a cycle, it can park the electric vehicles to charge at the right time. To the user it's a matter of saying 'I want to get to the conference at 9am' and the system will tell him what time a car will pick him up at his chosen pickup point.
Absolutely, and since Musk has an electric car company, something along those lines might be quite realistic. For electric cars used in that way, charging would not be an issue, as it would not be the burden of private car owners.
I just had another thought, although maybe a bit ridiculous: the main issue with "public cars" to me seems to me hygienic, how to keep them clean. What if in the future instead of owning whole cars, you only own a capsule with seats that can be picked up by transporters? I'd still prefer a world where parked car things are completely gone, but such capsules might still save a lot of space in the meantime.
I just had another thought, although maybe a bit ridiculous: the main issue with "public cars" to me seems to me hygienic, how to keep them clean. What if in the future instead of owning whole cars, you only own a capsule with seats that can be picked up by transporters? I'd still prefer a world where parked car things are completely gone, but such capsules might still save a lot of space in the meantime.
Pretty much every large supermarket I've been in in the UK and Ireland uses pressurized tubes to send money from the tills to the back office.
I have a problem with the quote "no rails required" because I would interpret that in a general sense, i.e. a Car does not need rails. To me, a tube just sounds like a special kind of rail.
However, all the most plausible theories I have heard so far, and my own possibility, all rely on some sort of (although not traditional) rails.
However, all the most plausible theories I have heard so far, and my own possibility, all rely on some sort of (although not traditional) rails.
Problems:
Digging a tunnel takes years and cost billions (see London underground new tunnel http://www.bbc.co.uk/news/business-16320945)
Making the tunnel fit the carrage = no room for emergency
Security (terrorists + bomb = nightmare at speed of sound)
Windows? What would you look at?
If he thinking of just goods (not people) then some of these problems are much simpler - the tunnel could be less than 1m in radius.
My wild idea is that he is going to us a rail gun to fire drones up a couple of KM into the air, these then glide down to mini airports. Replace freight railroads.
Digging a tunnel takes years and cost billions (see London underground new tunnel http://www.bbc.co.uk/news/business-16320945)
Making the tunnel fit the carrage = no room for emergency
Security (terrorists + bomb = nightmare at speed of sound)
Windows? What would you look at?
If he thinking of just goods (not people) then some of these problems are much simpler - the tunnel could be less than 1m in radius.
My wild idea is that he is going to us a rail gun to fire drones up a couple of KM into the air, these then glide down to mini airports. Replace freight railroads.
Terrorists + bomb = nightmare (regardless of speed).
By this logic Planes are a bad idea too (no room for emergency, high speed, tiny windows with nothing to look at)...
By this logic Planes are a bad idea too (no room for emergency, high speed, tiny windows with nothing to look at)...
You don't have to dig. Just place the metal shell on posts like an oil pipeline.
That's not it. From this article about Musk going to the UK[0], "it also can’t have a right of way issue, where people have to give up their homes." Your idea would be no different from high-speed rail in that regard.
0: http://techcrunch.com/2012/11/19/elon-musk-with-jobs-gone-go...
0: http://techcrunch.com/2012/11/19/elon-musk-with-jobs-gone-go...
Ah, good catch!
Now I'm really curious...
Now I'm really curious...
How about underground? Pretty capital intensive and a lot more work than aboveground but it would get around the right-of-way issues. Access at various intervals would be very expensive though. But at least it would be possible (with a space based loop not so much).
Musk also said it would cost less than going by plane. Unless he has some novel approach to creating underground tunnels that's radically cheaper than existing methods, I don't see how this could be possible.
People don't like windmills because they are "ugly".
They don't like power-lines in the country side.
They certainly wouldn't like a 2.5M+ diameter tube running around. In London, 56% (IIRC) of the "Underground" is above ground, much of that above road level.
They don't like power-lines in the country side.
They certainly wouldn't like a 2.5M+ diameter tube running around. In London, 56% (IIRC) of the "Underground" is above ground, much of that above road level.
we have a lot of wind turbines where I live. You get a strobe sounds of wuh-wuh-wuh-wuh-wuh if you are down wind of them. They are noisy. Also, if the sunlight catches them you also get a strobe reflection off them. That is also horrible.
There is a farmer who has 2 turbines up, he lives on the far side of a hill about a km away - you can still hear those whoosh-whoosh-whoosh all day long. Painful.
Powerlines also run over a lot of campsites near my house, you can hear them hummmmmm and crackle. In the damp/rain/mist/fog you can hear a lot of crackling and humming from them.
I can understand why people get angry with them. In urban areas where there is a lot of noise, I guess you wouldn't notice it so much.
Off topic, but my sister worked in a place where they put the magnets into wind turbines. There was a loud crash one day, someone had a magnet on a pallet, lifted it with a forklift and drove it out to a van. Half way the magnet got sucked by another magnet (in one of the factories) and burst through the wall and the two clamped together. They never got them apart and had to take the remaining bits of the turbine apart from around them.
There is a farmer who has 2 turbines up, he lives on the far side of a hill about a km away - you can still hear those whoosh-whoosh-whoosh all day long. Painful.
Powerlines also run over a lot of campsites near my house, you can hear them hummmmmm and crackle. In the damp/rain/mist/fog you can hear a lot of crackling and humming from them.
I can understand why people get angry with them. In urban areas where there is a lot of noise, I guess you wouldn't notice it so much.
Off topic, but my sister worked in a place where they put the magnets into wind turbines. There was a loud crash one day, someone had a magnet on a pallet, lifted it with a forklift and drove it out to a van. Half way the magnet got sucked by another magnet (in one of the factories) and burst through the wall and the two clamped together. They never got them apart and had to take the remaining bits of the turbine apart from around them.
> Off topic, but my sister worked in a place where they put the magnets into wind turbines. There was a loud crash one day, someone had a magnet on a pallet, lifted it with a forklift and drove it out to a van. Half way the magnet got sucked by another magnet (in one of the factories) and burst through the wall and the two clamped together. They never got them apart and had to take the remaining bits of the turbine apart from around them.
What city was this in? Which manufacturer?
What city was this in? Which manufacturer?
It beats looking at a 6 laner highway! And you could burry it halfway and still have easy access.
Interesting speculation by Jacques, but I think the combination of rail run and Concorde is a rail gun that fires hypersonic motor-less capsules that glide to destination.
Smaller landing zones, no air pollution, much less noise...
It's also a good combination of Telsa (rail gun) and SpaceX (rockets can be seen as motorized slugs).
Only limit I see with this system is that I'm not sure anyone could withstand the acceleration.
Smaller landing zones, no air pollution, much less noise...
It's also a good combination of Telsa (rail gun) and SpaceX (rockets can be seen as motorized slugs).
Only limit I see with this system is that I'm not sure anyone could withstand the acceleration.
A sling would be much better for this: it's much smaller than a huge gun and also more flexible since the direction and elevation can be changed by altering the release point and axis.
Centripetal acceleration is a = v^2 / r so for 300 m/s (about mach 1) speeds, for 1 gee centripetal acceleration you'd need 9 km radius.
Centripetal acceleration is a = v^2 / r so for 300 m/s (about mach 1) speeds, for 1 gee centripetal acceleration you'd need 9 km radius.
Maybe this sling is the "loop" in Hyperloop.
That's the only limit? To big guns that fire people?!
I think this is it. Wrote about it here:
http://dylanized.com/the-hyperloop/
http://dylanized.com/the-hyperloop/
That makes quite a lot of sense. Air resistance could be a problem though. I guess if it was a loop, air could travel inside the tube but then you run into friction problems - it takes a lot of energy to keep the air running.
The nice thing about acceleration is that you only need to wait a bit longer to get to the desired velocity.
First time I read it wouldn't be an evacuated tunnel. Next thought of technology it could use then then jumps to maglev-like technology; Imagine a Tesla vehicle (or others) that can hop onto a network that brings the vehicle onto a maglev system, reducing friction (and other elements wouldn't really effect it, especially if you decided to put a canopy over it) ; Anyone else realize he may have dropped a hint in this video (http://video.ft.com/v/1974478965001/Elon-Musk-from-electric-... ) that we might see flying cars?
You'd need on-ramps, where a minimum speed is required before merging with the main line, and of course you'd only build on/off ramps at major hubs. The only issue I see being you're not using tar then, and therefore costs of raw materials would be higher, at least initially, and would likely last longer than tar.
Being cheaper than highspeed rail could fit into this equation because its the vehicle owners paying for the vehicle, and no trains are being build for it - so actual money going into the system, the synergies that would exist, might be greater - though putting it how he does is creating lots of attention. :)
Maybe the hyperloop refers to a an on/off ramping system, where you get accelerated to a certain speed... Fun speculating. And time for tea and breakfast.
You'd need on-ramps, where a minimum speed is required before merging with the main line, and of course you'd only build on/off ramps at major hubs. The only issue I see being you're not using tar then, and therefore costs of raw materials would be higher, at least initially, and would likely last longer than tar.
Being cheaper than highspeed rail could fit into this equation because its the vehicle owners paying for the vehicle, and no trains are being build for it - so actual money going into the system, the synergies that would exist, might be greater - though putting it how he does is creating lots of attention. :)
Maybe the hyperloop refers to a an on/off ramping system, where you get accelerated to a certain speed... Fun speculating. And time for tea and breakfast.
All great points, but I will point out that the major cost item on high speed (or any rail for that matter) is the rail itself. The cars and locomotive are relatively cheap, but you're looking at figures of $1M+ USD per mile of track.
If/when self-driving cars succeed in being ready for public consumption, I think a huge opening for revolutions in transportation gets opened up.
- If you can call your car, it can park farther away. Parking is one of the biggest problems with cars in urban areas.
- Instead of calling of your car, you could just call a car. A self driving car and a self driving taxi are pretty similar, but one can run 24hrs and reduce the parking problem more.
- Computers can do things people can't do. Once enough auto-automobiles are out there, there can be autoauto only "features". The same square footage of tarmac might be able to move cars much quicker. Maybe autoautos can handle 200km speeds. Maybe they can cooperate to make traffic smoother. Maybe they can link together like trains to overcome congestion.
There is nothing quite as good as having a car to take you exactly to and from where you want to go. If self driving cars can really mix with human drivers everywhere they may have a nice smooth path to innovate on gradually. Big vision plans for revolutionizing transport are so centralized, so premeditated.
edit: one more thing. self driving cars interact in an interesting way with public/mass trasport, especially if people dont own their own. It may reduce the demand by competing more directly on one hand. OTOH, it will compliment by providing the last-mile component.
- If you can call your car, it can park farther away. Parking is one of the biggest problems with cars in urban areas.
- Instead of calling of your car, you could just call a car. A self driving car and a self driving taxi are pretty similar, but one can run 24hrs and reduce the parking problem more.
- Computers can do things people can't do. Once enough auto-automobiles are out there, there can be autoauto only "features". The same square footage of tarmac might be able to move cars much quicker. Maybe autoautos can handle 200km speeds. Maybe they can cooperate to make traffic smoother. Maybe they can link together like trains to overcome congestion.
There is nothing quite as good as having a car to take you exactly to and from where you want to go. If self driving cars can really mix with human drivers everywhere they may have a nice smooth path to innovate on gradually. Big vision plans for revolutionizing transport are so centralized, so premeditated.
edit: one more thing. self driving cars interact in an interesting way with public/mass trasport, especially if people dont own their own. It may reduce the demand by competing more directly on one hand. OTOH, it will compliment by providing the last-mile component.
Maybe they can dent the number of fatalities from human error. There is a hurdle in overcoming public perception. People say they wouldn't want to put their life in control of some automated computer, yet they put their life in the hands of thousands of other drivers every single day they drive.
In the US we accept 10000 fatalities annually from drunk drivers alone. Vietnam killed nearly 60000 and wounded countless others over the course of 20 years. In just the last 20 we've accepted more than 200,000 alcohol related deaths just getting from point A to point B.
So when people are afraid of a glitch in the system causing a pile up it is worth remembering such tragedies are possible, but it would still be something that could be corrected.
In the US we accept 10000 fatalities annually from drunk drivers alone. Vietnam killed nearly 60000 and wounded countless others over the course of 20 years. In just the last 20 we've accepted more than 200,000 alcohol related deaths just getting from point A to point B.
So when people are afraid of a glitch in the system causing a pile up it is worth remembering such tragedies are possible, but it would still be something that could be corrected.
No matter how closely together the cars can drive, as long as you have an engine and a crash-resistant shell around each passenger, it will never be as space-efficient was the 35' Gillig Advantage I am sitting in right now.
IMO the best application of self-driving cars in an urban landscape is last-mile demand for people who live outside the city, where it's not economical to run buses or trains. But inside a city proper, or even on a busy freeway, having one car per passenger takes up a lot of space that could be better used elsewhere, both while moving and while parked.
(Also, self-driving technology could be applied to buses and streetcars to reduce operating costs and expand frequency and range of service.)
IMO the best application of self-driving cars in an urban landscape is last-mile demand for people who live outside the city, where it's not economical to run buses or trains. But inside a city proper, or even on a busy freeway, having one car per passenger takes up a lot of space that could be better used elsewhere, both while moving and while parked.
(Also, self-driving technology could be applied to buses and streetcars to reduce operating costs and expand frequency and range of service.)
Just imaging self-driving minibuses.
Public transport minibuses might actually be a good place to exercise self driving vehicles.
Minibuses don't need the same versatility as consumer cars have. They "only" need to be able to handle anything they can encounter on a predefined route. The route itself could even be optimized for them (eg pedestrian barriers).
Minibuses don't need the same versatility as consumer cars have. They "only" need to be able to handle anything they can encounter on a predefined route. The route itself could even be optimized for them (eg pedestrian barriers).
Preface: my primary modes of transportation (in my city) are walking, biking, and subway.
God, I cannot wait for either hyper loop or self driving cars (I'm sure we'll see the latter first). I live in Northern California and have family in Southern California. We're starting to flip the holidays this year (wife's family for thanksgiving, mine for Xmas). Just went down to LA for a friends wedding and the drive was horrendous.
A lot of factors come into play:
1, as much as I've hated them in the past, a big suv (especially with a kid) is the way to go. We have a VW Passat (wife's) and it was so crammed it was ridiculous. Very uncomfortable and it's not even a compact. 2, I'm over 40 now and it just physically hurts to drive for 7 hours. I was totally sore the next day. Frickin sucked. 3, Directions. I totally need navigation now. Even with the turn by turn on my phone, I still made wrong turns. 4, I hate driving. Hate it. I see it as such a waste of time. I can't imagine needing to drive to make a living. In my late teens and early 20's when I lived in Southern California, I hade to do just that. After I moved to the city I vowed I never would again. 5, Other drivers. I was pretty appalled by some of the drivers on the road. I kept thinking, I can't wait for computers to handle this so that guy driving down the emergency lane wouldn't be able to.
If I could just hop in a driverless car for that drive, it would be great. I could nap, read, compute, converse, etc. Things I can't do now. I'm sure there's going to be some resistance at first by those with a 'god given right' to drive. But after a while, I see common sense prevailing.
I listened to a great talk at The Long Now Foundation by Tim O'Reilly. He was talking about driverless cars and how the DARPA car challenge when it started could only do around 7 miles. It wasn't the algorithms that got that much better (although I'm sure they did) for the Google cars, it was the data set. Google Maps was a huge advantage and the 'killer app' for the latest generation of their cars.
So a lot to look forward to in this arena. I think my kid will grow up with the internal combustion car for him being like the 8-track for me.
God, I cannot wait for either hyper loop or self driving cars (I'm sure we'll see the latter first). I live in Northern California and have family in Southern California. We're starting to flip the holidays this year (wife's family for thanksgiving, mine for Xmas). Just went down to LA for a friends wedding and the drive was horrendous.
A lot of factors come into play:
1, as much as I've hated them in the past, a big suv (especially with a kid) is the way to go. We have a VW Passat (wife's) and it was so crammed it was ridiculous. Very uncomfortable and it's not even a compact. 2, I'm over 40 now and it just physically hurts to drive for 7 hours. I was totally sore the next day. Frickin sucked. 3, Directions. I totally need navigation now. Even with the turn by turn on my phone, I still made wrong turns. 4, I hate driving. Hate it. I see it as such a waste of time. I can't imagine needing to drive to make a living. In my late teens and early 20's when I lived in Southern California, I hade to do just that. After I moved to the city I vowed I never would again. 5, Other drivers. I was pretty appalled by some of the drivers on the road. I kept thinking, I can't wait for computers to handle this so that guy driving down the emergency lane wouldn't be able to.
If I could just hop in a driverless car for that drive, it would be great. I could nap, read, compute, converse, etc. Things I can't do now. I'm sure there's going to be some resistance at first by those with a 'god given right' to drive. But after a while, I see common sense prevailing.
I listened to a great talk at The Long Now Foundation by Tim O'Reilly. He was talking about driverless cars and how the DARPA car challenge when it started could only do around 7 miles. It wasn't the algorithms that got that much better (although I'm sure they did) for the Google cars, it was the data set. Google Maps was a huge advantage and the 'killer app' for the latest generation of their cars.
So a lot to look forward to in this arena. I think my kid will grow up with the internal combustion car for him being like the 8-track for me.
Though a rarely brought up fact when discussing self-driving vehicles, planes have been on the right track for the last few decades with autopilot. The automotive industry should take some lessons learned from the government regulatory structure, and avionic makers, and build a system capable of high capacity traffic with extremely low fatality rates.
Issues that we deal with when driving an automobile are amplified 100x when in the cockpit of an aircraft. Traffic is nearly impossible to spot during the day time without someone like an air traffic controller (ATC) telling you about it. Managing a plane in inclement weather is an effort in bravery and extraordinary situational decision making. Crashes, though statistically unlikely to be fatal, can have extreme consequences for both passengers an innocent by-standers. All-in-all, the experience of flying is just plain difficult. There are dozens of controls to handle at any given moment, and even the distractions are amplified (ever tried writing something down while driving? It happens in planes all the time)
So how did we overcome these issues? Regulations and technology. Just looking at the traffic issue, there are rules for which alititude to fly at for which direction and type of flight you are, rules for entering high traffic areas by verifying you have communicated intentions first, rules for what equipment your plane has to have before entering specific high traffic areas, and strict expectations that pilots will be able to control their aircraft to the best of their ability. There is plenty of redundancy in the system as well.
I would venture to say that landing a plane is much more demanding than driving a car, even in the most severe driving conditions, yet we trust autopilots to set the plane down in even the most severe 0 visibility scenarios (http://www.youtube.com/watch?v=7BUA3EwKpVM). The technology in vehicles is beginning to make sense to implement in the same way we have it present in airplanes right now, but I would love to see the regulatory structure begin to step up and build a reasonable, redundant, and safe system for driving an driver-less car. Then I can see the world you are describing.
Issues that we deal with when driving an automobile are amplified 100x when in the cockpit of an aircraft. Traffic is nearly impossible to spot during the day time without someone like an air traffic controller (ATC) telling you about it. Managing a plane in inclement weather is an effort in bravery and extraordinary situational decision making. Crashes, though statistically unlikely to be fatal, can have extreme consequences for both passengers an innocent by-standers. All-in-all, the experience of flying is just plain difficult. There are dozens of controls to handle at any given moment, and even the distractions are amplified (ever tried writing something down while driving? It happens in planes all the time)
So how did we overcome these issues? Regulations and technology. Just looking at the traffic issue, there are rules for which alititude to fly at for which direction and type of flight you are, rules for entering high traffic areas by verifying you have communicated intentions first, rules for what equipment your plane has to have before entering specific high traffic areas, and strict expectations that pilots will be able to control their aircraft to the best of their ability. There is plenty of redundancy in the system as well.
I would venture to say that landing a plane is much more demanding than driving a car, even in the most severe driving conditions, yet we trust autopilots to set the plane down in even the most severe 0 visibility scenarios (http://www.youtube.com/watch?v=7BUA3EwKpVM). The technology in vehicles is beginning to make sense to implement in the same way we have it present in airplanes right now, but I would love to see the regulatory structure begin to step up and build a reasonable, redundant, and safe system for driving an driver-less car. Then I can see the world you are describing.
I agree.
And:
- On a long journey, you can read, watch a film, surf the net or sleep. Overnighters become an option.
- Too drunk to drive yourself home? No problem. Too young? Likewise.
- No driver's licence? No problem. A driver's licence may eventually become a niche thing to have, like a pilot's licence.
And:
- On a long journey, you can read, watch a film, surf the net or sleep. Overnighters become an option.
- Too drunk to drive yourself home? No problem. Too young? Likewise.
- No driver's licence? No problem. A driver's licence may eventually become a niche thing to have, like a pilot's licence.
This. Between this and delivery drones, is our nearby future of transportation.
I honestly don't think delivery drones are going to be a widespread thing. Too many problems that you can encounter that lose you an expensive drone that wouldn't lose you a simple high school age delivery driver.
Drones are not expensive at all (you can buy one for $300), and will only get cheaper.
It would be awesome to call a random car any time you want, but I hate to think of the mess some people would leave in it once they were done with it.
You can never avoid this, but take an approach like ZipCar:
http://www.zipcar.com/how/faqs/how-are-cars-cleaned
In almost two years of being a ZipCar client, I've never had any issues. Yes, the occasional coke can or candy wrapper left behind, but never a mess that I thought to be unreasonable.
If it turns out to be a bigger problem, install a camera that takes a shot when you take possession of the car, and when you relinquish it. Charge the renters credit card for messiness.
In almost two years of being a ZipCar client, I've never had any issues. Yes, the occasional coke can or candy wrapper left behind, but never a mess that I thought to be unreasonable.
If it turns out to be a bigger problem, install a camera that takes a shot when you take possession of the car, and when you relinquish it. Charge the renters credit card for messiness.
> install a camera that takes a shot when you take possession of the car, and when you relinquish it.
Such a system would be good to have anyway as part of a dashcam. One facing forward, and a fish-eye facing the rear window and also capturing the interior of the car. I am hoping that car insurance companies will start offering discounts for cars with installed dashcams.
A tangent of a tangent now, this would be great (though creepy) for public restrooms. Given that there's a physical method, like positioning on the door, that prohibits it from seeing anything while the stall door is closed or locked, I think it would cut down on the seriously depraved messes people leave behind when they know they can get away with it.
Such a system would be good to have anyway as part of a dashcam. One facing forward, and a fish-eye facing the rear window and also capturing the interior of the car. I am hoping that car insurance companies will start offering discounts for cars with installed dashcams.
A tangent of a tangent now, this would be great (though creepy) for public restrooms. Given that there's a physical method, like positioning on the door, that prohibits it from seeing anything while the stall door is closed or locked, I think it would cut down on the seriously depraved messes people leave behind when they know they can get away with it.
I use zip cars a lot and never had a problem as well.
Yeah. They would probably have to be cleaned pretty regularly.
It's terrible to think that people invent cars, then make them driverless, then make them come pick you up from anywhere when you whistle (or press a button on your phone) but the bottleneck that we can't solve is inconsiderate assholes leaving fish and chip rubbish in the back seat.
It's terrible to think that people invent cars, then make them driverless, then make them come pick you up from anywhere when you whistle (or press a button on your phone) but the bottleneck that we can't solve is inconsiderate assholes leaving fish and chip rubbish in the back seat.
Solvable with a combination of:
- reputation systems
- computer vision / cameras / contract law
- price discrimination based on the required state of the vehicle (i.e., premium pricing for a guarantee that a vehicle has been cleaned)
- reputation systems
- computer vision / cameras / contract law
- price discrimination based on the required state of the vehicle (i.e., premium pricing for a guarantee that a vehicle has been cleaned)
or a premium price for leaving a vehicle in a sorry state
Yeah I was implying that with my second point, sorry for not being clear.
OK, we are in agreement then. For some reason I thought you meant charging more for wanting a clean vehicle. I'd rather charge more for people who leave the car in a messy state (because they are in a hurry or something)
Yes, the third point was about charging more for clean vehicles, the second point about charging people for not leaving their vehicles behind clean.
But yeah, I do think we agree :)
But yeah, I do think we agree :)
> Maybe autoautos can handle 200km speeds.
You can do more with normal cars today, already. (In fact, I've done so.) The economics of those speeds just don't add up for cars.
You can do more with normal cars today, already. (In fact, I've done so.) The economics of those speeds just don't add up for cars.
Rather than self-driving cars, I see hype-loop kind of system being more effective overall(reliable, cheaper). Obviously a lot more work has been done(Google) on self-driving cars but I would secretly hope/wish that Elon really gets cracking on this thing(especially since he has to regular suffer one of the worst commutes in the world - 405 freeway in LA - especially that particular section).
Sorry to be the pernickety one, Jacque but inyour opening sentence: "For a while now there are tantalizing hints that Elon Musk is at it again." isn't correct English since "are" is the wrong tense.
Try "For a while now there have been tantalizing hints that Elon Musk is at it again"
Or perhaps better: "There have been tantalizing hints that Elon Musk is at it again for a while now"
Try "For a while now there have been tantalizing hints that Elon Musk is at it again"
Or perhaps better: "There have been tantalizing hints that Elon Musk is at it again for a while now"
If your sorry to be that guy, perhaps send Jacques an email instead of posting on a public forum. Unless your not so sorry that you had to be 'that' guy.
Looking to me like router/hub concept in the real world called Hyperloop. You have network (pressured tunnels) with packets (packets which carry me around Hyperloop) controlled via nodes aka router/hub (locations where people could board). Brilliant.
Sorry Jacques, I'm sticking to the suborbital maglev thing.
Yeah, I know it's a long-shot, but it fits into my idea of Musk better than a giant mail tube. I'm just seeing pressurized tubes scaling. There's the same problem with the orbital sub-loop, but I'm betting Musk spent a lot of time looking at this idea as part of his Mars dream.
One thing's for sure -- it's going to be a blast seeing how it all turns out!
Yeah, I know it's a long-shot, but it fits into my idea of Musk better than a giant mail tube. I'm just seeing pressurized tubes scaling. There's the same problem with the orbital sub-loop, but I'm betting Musk spent a lot of time looking at this idea as part of his Mars dream.
One thing's for sure -- it's going to be a blast seeing how it all turns out!
Didn't he say in the Ariane 5 is dead interview that it's a cross between a Concorde and a rail gun, so think super streamlined glider, launched by maglev, captured by maglev (recovering some energy energy on capture). High speed rail without most of the rail.
The big issue would be air traffic control at launch and landing. 600 m/s (Mach 2) at 0.5g acceleration would require 36km of launch rail which is kind of a lot. But you could loop the track and reduce the acceleration to make up for centripetal forces — a 200m radius loop might be about right, and once you use a loop you can go a lot faster (and this explains the name: hypersonic loop).
I suppose it might skip short distances requiring pylons or something for speed top ups and travel at lower speed.
The big issue would be air traffic control at launch and landing. 600 m/s (Mach 2) at 0.5g acceleration would require 36km of launch rail which is kind of a lot. But you could loop the track and reduce the acceleration to make up for centripetal forces — a 200m radius loop might be about right, and once you use a loop you can go a lot faster (and this explains the name: hypersonic loop).
I suppose it might skip short distances requiring pylons or something for speed top ups and travel at lower speed.
I figure it is a side by side maglev with a bunch of mass going around one of the tracks to store energy.
That's assuming the mass needs to be on a second track to maintain a schedule. I guess it's probably possible to do something clever at the stations to avoid a second track.
That's assuming the mass needs to be on a second track to maintain a schedule. I guess it's probably possible to do something clever at the stations to avoid a second track.
Everyone's assuming Musk has the answer and we're guessing at it. I feel like he's prompting the world to create the answer. True leadership at its finest. Define the problem, broad brush what the solution could and should be and then watch minds go to work.
I don't think that this is what he is doing but this definitely crossed my mind over the past few weeks. It's pretty awesome how inspiring a person like Elon could be. A year ago, the general public and geek community didn't really talk all that much about alternative modes of transportation. Now, all because of Musk, everyone is all of a sudden trying to come with a new idea.
If that is the case, the name is clearly appropriate.
Hype-er loop.
Hype-er loop.
Elon Musk > Chuck Norris
I suspect that it is a beneath the road electrical induction charging system so that cars/vehicles don't need to carry heavy batteries to travel longer distances..
On open roads, where batteries fall down on range, surely this would make sense? Combine with self drive for easy town to town driving experience.
On open roads, where batteries fall down on range, surely this would make sense? Combine with self drive for easy town to town driving experience.
I think that you ALMOST have it. You've even explained the following tantalizing quote from July: I think we could actually make it self-powering if you put solar panels on it, you generate more power than you would consume in the system. There's a way to store the power so it would run 24/7 without using batteries. Yes, this is possible, absolutely. The cars in the loop store power. A lot of it.
Now why do I say almost? Let's make one small modification. Let's put a lot of one way flaps in the tube so that it is easy for a puff of air to blow out, but not so easy for air to come back in. There would be leakage, but that is going to be OK.
As each car comes by, it piles up air in front of it that blows out of the flaps. Then the flaps fall back, and maintains a partial vacuum. The partial vacuum is no problem for people because there is a pile of air in front of their car that can be tapped for breathing air, that can then be released backwards, where it circulates through the tube (and probably out the flap).
This makes his evacuated tube comment even more of a teasing joke. No, the tube is not evacuated. Nor did you pump air out of it. But it winds up almost evacuated. However it is still fine for breathing.
Now the point is that reduced air pressure inside of the tunnel significantly reduces drag caused by the air dragging on the edges of the tunnel and being pushed by the cars. This does a lot to make the whole thing massively more efficient. Elon's claim is then that it is efficient enough that it can be powered by solar panels placed on the tube.
My big question is how hot it will be. There may be very little gas in the tube, but that gas will be very, very hot. Over time the cars will heat up as well. So you'd need to have the cars regularly coming in and out of the system so that they would have time to cool down.
The practical difficulties in building this are immense. But I do not see any physical reason why it is impossible.
Now why do I say almost? Let's make one small modification. Let's put a lot of one way flaps in the tube so that it is easy for a puff of air to blow out, but not so easy for air to come back in. There would be leakage, but that is going to be OK.
As each car comes by, it piles up air in front of it that blows out of the flaps. Then the flaps fall back, and maintains a partial vacuum. The partial vacuum is no problem for people because there is a pile of air in front of their car that can be tapped for breathing air, that can then be released backwards, where it circulates through the tube (and probably out the flap).
This makes his evacuated tube comment even more of a teasing joke. No, the tube is not evacuated. Nor did you pump air out of it. But it winds up almost evacuated. However it is still fine for breathing.
Now the point is that reduced air pressure inside of the tunnel significantly reduces drag caused by the air dragging on the edges of the tunnel and being pushed by the cars. This does a lot to make the whole thing massively more efficient. Elon's claim is then that it is efficient enough that it can be powered by solar panels placed on the tube.
My big question is how hot it will be. There may be very little gas in the tube, but that gas will be very, very hot. Over time the cars will heat up as well. So you'd need to have the cars regularly coming in and out of the system so that they would have time to cool down.
The practical difficulties in building this are immense. But I do not see any physical reason why it is impossible.
hey Ben, I think that the gas won't get too hot because it has all of the surface of the sheath to cool it. But that's a precarious balance, and it will need some pretty good book keeping to make sure that all the power generated on a stretch 'x' meters long gets radiated out from the tube to keep the temperature stable.
As for the flaps, you're right, I didn't think that bit through, I'm not quite sure what the best solution would be there. But if that's the only thing wrong with what I sketched I'll be pretty happy.
As for the flaps, you're right, I didn't think that bit through, I'm not quite sure what the best solution would be there. But if that's the only thing wrong with what I sketched I'll be pretty happy.
The problem is that if you're moving fast against a cool surface, friction does more to make you hot than conduction does to make you cool. Furthermore even if the gas was room temperature, the air touching the car has just been compressed by a shock wave. Rapidly compressing gas makes it become very, very hot. Because of both effects, the car is going to be permanently exposed to very hot gas.
But I'm sure Elon has thought about that aspect and it is solvable.
But I'm sure Elon has thought about that aspect and it is solvable.
Hm, tricky. Somehow you'd think that that part of the gas that is exposed to friction is limited to the portion that was slowed down by the interaction with the wall, and that the rest of the gas would not be subject to this because it is moving at roughly the same speed as the carriages.
During the acceleration phase this would definitely be an issue, the gas in front of the carriage would be compressed because the carriage is moving much faster than that body of gas. But that (hot) gas could be dumped just prior to insertion of the carriage into the tube.
Maybe the outside of the 'sheath' could be made from a heatsink like profile? I haven't given the thermodynamics of the thing much thought, I was basically just trying to figure out a solution that would not require some far-out technology.
I know that lots of people like to link space with Elon Musk but I think he's much more practical than that, space is a means for him to get to mars and Nasa a convenient way to finance it.
Other than that Tesla doesn't have anything to do with space and is ground transportation, I don't see any reason to go into low earth orbit with all the associated risks if you could do the whole thing on the ground and be:
That's mostly a surface area increase problem, the air over a highway is notably warmer than the air around it simply because all those cars dump the combined energy of burning all their fuel into the environment. If you can reduce the energy input into the system then you'll reduce the amount of energy you have to get rid of afterwards. So I can see that reducing that input energy is really important and that changing the speed of the cars is brutal in this respect because it causes the air behind it to pile up against it (heating it up) when decelerating (but the air in front would cool down due to expansion) and vice versa.
It's an interesting problem and if I wouldn't have a ton of other stuff to do I'd happily cook up a simulator for this.
During the acceleration phase this would definitely be an issue, the gas in front of the carriage would be compressed because the carriage is moving much faster than that body of gas. But that (hot) gas could be dumped just prior to insertion of the carriage into the tube.
Maybe the outside of the 'sheath' could be made from a heatsink like profile? I haven't given the thermodynamics of the thing much thought, I was basically just trying to figure out a solution that would not require some far-out technology.
I know that lots of people like to link space with Elon Musk but I think he's much more practical than that, space is a means for him to get to mars and Nasa a convenient way to finance it.
Other than that Tesla doesn't have anything to do with space and is ground transportation, I don't see any reason to go into low earth orbit with all the associated risks if you could do the whole thing on the ground and be:
- safer
- as fast
- not have the energy expenditure of having to work
against gravity
- easier to maintain
- shorter path
That's mostly a surface area increase problem, the air over a highway is notably warmer than the air around it simply because all those cars dump the combined energy of burning all their fuel into the environment. If you can reduce the energy input into the system then you'll reduce the amount of energy you have to get rid of afterwards. So I can see that reducing that input energy is really important and that changing the speed of the cars is brutal in this respect because it causes the air behind it to pile up against it (heating it up) when decelerating (but the air in front would cool down due to expansion) and vice versa.
It's an interesting problem and if I wouldn't have a ton of other stuff to do I'd happily cook up a simulator for this.
I have figured out a solution to the heat problem, but it looks rather different.
I'll do a blog post later today with it. But now I have to get my daughter to school.
I'll do a blog post later today with it. But now I have to get my daughter to school.
Blog post posted to http://bentilly.blogspot.com/2012/11/speculating-about-hyper... and with any luck there will be discussion about my version of the idea at http://news.ycombinator.com/item?id=4815665.
Moving the air through the tunnel addresses the capsule drag, but now you have drag between your moving air and the tunnel wall, which depending on the distance between vehicles is going to be a larger loss.
Yacht designers refer to the "wetted area" component of drag, and an entire tunnel wall is a heck of a lot of wetted area.
Yacht designers refer to the "wetted area" component of drag, and an entire tunnel wall is a heck of a lot of wetted area.
Would it be possible to run a partial vacuum just in the space between the vehicle and the tunnel wall, for instance by having the vehicle body be slightly curved away from the wall except at the end points?
And, of course, the skin friction on a 2.5 meter tunnel would be immense. Using a duct friction loss calculator I get 285 megawatts of loss over the entire tube. You need two tubes. At 120,000 passengers/day (HSR estimate), it would take 114 kWh per trip. That's worst than the Model S, hardly an system in which "the fundamental energy cost is so much lower" than a car.
No, the "theoretically fastest way" to go from Point A to Point B is a great-circle vacuum train connecting them. A launch loop does essentially that, but exploits the vacuum above our heads instead. It just fits better.
Any hyperloop theory needs to deal with supersonic speeds – LA-SF as the crow flies in 30 minutes is just under the wire for subsonic speeds. Elon said "under 30 minutes." There are mountains in the way.