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Tectonic Plate Pulling Power

Harness continental drift for the betterment of humanity
  (+6, -3)
(+6, -3)
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against]

First, stretch a carbon-fiber, high-tensile, titanium cable across the Atlantic between Nova Scotia and Ireland. At both ends, the slow but powerful pull of the few cm per year continental drift is geared up to drive generators. The resulting energy could power millions of PCs in front of millions of satisfied halfbakers. A similar cable would have to be drawn between South America and Africa so that the western hemisphere wouldn't be broken at the Panama Canal.

Every four years, the cable movement would be locked at each end, and a GPS station connected to the middle would reveal, after a month, the winners of continental tugs of war. In the next event, a GPS station on New Zeeland would register its "jump" on a bungee cord stretched from Japan.

FarmerJohn, May 11 2002


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       please do not try to tell me there are *millions* of satisfied half-bakers. a fishy for that thought and a croissant for "continental tug of wars" cancel each other out.
po, May 11 2002
  

       As opposed to Po, I rather enjoy the idea of millions of Half-Bakers (sometime in the future) who are aided by your cross-Atlantic cables.   

       In the meantime, I worry about ships' propellers getting caught in those lines stretched across the shipping channels. (After all, if there's no taut stretch, there's no energy being captivated, right?)
jurist, May 11 2002
  

       A taut stretch would probably still have the cables lying, for the majority of the distance, on the sea floor. Don't forget the curvature of the earth.
yamahito, May 11 2002
  

       Think of two horses walking s l o w l y away from each other to lift a sumo wrestler in a hammock - that's 2 hp.
FarmerJohn, May 11 2002
  

       Mount a giant cuckoo clock on the back of each horse. The hammock ropes would pull up the clocks' weights, "winding" them.
FarmerJohn, May 11 2002
  

       Use the wire to pull a piston, and thru a series of gears increase the rotational speed until it's fast enough to drive a conventional turbine-driven power generator. Anyone care to calculate the force on each end necessary for a decent power output?   

       Work (energy) = force x distance. Force = energy / distance. Distance = 0.1 m per year, as an estimate. Say we want 1 MW output, puny by power station standards. That is 3 x 10^13 Joules per year, or dividing we get a force of 3 x 10^14 newtons, equal to the weight of 30 billion metric tonnes pulling on the cable, no?   

       Of course, that says nothing about the energy actually available, just the stresses required to generate a decent output.
pottedstu, May 11 2002
  

       I've actually seen sumo wrestlers winding their clocks exactly as you've described, so I know you know what you're talking about. You've covered the obvious risk at Panama, but I'm still concerned the North American continent might be torn in half at the Mississippi? Maybe a bunch of hammocks could help hold things together there? +
spartanica, May 11 2002
  

       I think you'd get more tug on the cable from things like temperature fluctuation and ocean currents than you would from continental drift. A lot more.
beauxeault, May 11 2002
  

       [spartanica] But how are you gonna get a rope across the Mississippi? That's practically insurmountable.   

       [pottedstu, beauxeault] A force that creates mountains and earthquakes should easily produce 30 trillion newtons.
FarmerJohn, May 11 2002
  

       FarmerJohn: And how big a cable would you need to support 30 billion newtons? How would you anchor it to the ground? I think the engineering considerations would be somewhat formidable.
pottedstu, May 11 2002
  

       Instead of runing a single cable between all the continents. why not many cables going across the San Andreas fault line. But one thing you forgot about is relativity. One end of the cable would have to be fixed so that it is not moving relative to the plate movements, the second end would have to be connected to some type of a recipricateing wheel or piston. But the piston (or wheel) would also have to be fixed in place. This means we would require 100 times as much potential energy to hold the system in place (alot of concrete) And that would most likely exceed the standard soil bearing capacity, and most likely would be to deep to dig. So either both ends would have to be static or the device could be placed in the center and their the device would have to be held static. I'm not an expert on foundations so I don't know what the answer would be to all this but if you can find away around all this then go for it, but until then i'n afraid I have to fish bone this idea. If there is anything here you don't understand or I didn't spell correctly then just read it over agian until you do understand, OK.
wood2coal, May 11 2002
  

       I thought this was Teutonic Plate Pulling Power
<pedant>New Zealand</pedant>
thumbwax, May 11 2002
  

       If you think of starting a lawnmower by pulling on the cord, except you are extremely strong, the cord is only pulled a nanometer and the mower has an extensive gear train that translates the slow tug into the rpm needed to start.
FarmerJohn, May 12 2002
  

       I rather like the idea of having a cable attached to the east coast of America at one end and the Leaning Tower of Pisa at the other. Just to keep the tower upright.
DrBob, May 12 2002
  

       You wouldn't actually have to stretch it across the whole atlantic. Simply fasten the cable on one side of the mid-Atlantic ridge, and set the clockwork machine on the other. I'm not certain how you'd get that power back to the continent. Perhaps you'd have the plates set a gigantic spring, which could be cocked into place, and then unwound once it was transferred ashore?   

       There are some serious hurdles to overcome, however. For instance, the gearing ratio would be have to be so astronomical that friction and gear binding would become an obvious barrier. Secondly, the cable material would have to be nightmarishly strong in order to not stretch, which would make it too brittle to work. The cable would be too thick to be wound on any spool, but that doesn't seem to be a problem. But then there's the heat issue. You'd have to find a 'cool' spot in the mid-ocean ridge, which I'm not certain exists, or at least anchor the machine and the far cable end in such a way that they're elevated from the hot floor. Lot's of engineering to overcome, but definitely worthy of a croissant.   

       A more likely variant might simply use the magma heat energy and hot water vents to power a turbine of some sort. <off-topic> Speaking of volcanoes and such, all of Yellowstone National is one gigantic supervolcano mouth, and is supposedly due to blow at anytime now, give or take a few thousand years. The last time that happened, 600k years ago, most of North America was covered in a few feet of ash.
RayfordSteele, May 13 2002
  

       Near infinite/infinitesimal gear ratios *are* possible at acceptable efficiencies- with hydraulics. Lots of other great reasons this idea sucks though...
shameless_self_reference, Sep 04 2002
  

       I love this idea! We could also tie a rubberband to one continent and tie it to the backs of the evil greedy oil tycoons and sling shot them into space!   

       Could this idea cause earthquakes or screw up things?
JoeLounsbury, Feb 25 2004
  

       This idea is stupid. It is obvious that many of the people voting for this idea don't even understand plate tectonics. First of all, a cable as long as you are suggesting, would break under its own weight long before tectonic stresses would break the cable. Second, the idea of attaching the cable to the MOR wouldn't work beacuse both the Europe side and North American side of the Atlanitc are passive continental margins. If this idea could work it would be best to simply attach the cable to anchors on the sea floor on both sides of the MOR. Of course, the cable would have to be stronger than anything known to man and this wouldn't work anyway because the rock around the anchor would break before the cable.
Hrothgar, Feb 29 2004
  

       am with [hrothgar] here. This idea would only work if the cable its elf was in full tension and unfortunately, due to the enormous forces involved, the cable would not last long at full tension.   

       however, I'm unsure what [hrothgar] means when he/she says that the M-Atlantic-R is a passive continental boundary - it is without question a divergent plate boundary, currently moving some 2-3cm per year.   

       anyhoos, [farmerjohn], I'm afraid I'm compelled to fish - this one won't work.
jonthegeologist, Mar 01 2004
  

       Presumably the cable(s) would only have to stretch across the width of the mid-Atlantic Ridge rather than across the entire width of the ocean, in order to generate the same amount of energy, so an impossibly long cable isn't really required in order to make the idea workable (sort of ).
DrBob, Mar 01 2004
  

       First of all the Mid Atlantic ridge is a divergent plate margin, what I said before is that the east coast NA and west cost Europe are PASSIVE margins (not convenrgent, no subduction). As I said before, one could anchor a shorter cable on both sides of the MOR. It's justy to bad the cable would have to be impossibly strong.
Hrothgar, Mar 12 2004
  

       And if we fill the spaces between tectonic plates with custard and when it's squeezed out we use it to turn a custard axial flow turbine?. And I like custard too.
finflazo, Apr 22 2004
  

       Hmm, I was thinking the same thing but using an axle wedged into a sheering fault. Think of rolling a pencil between your hands. you could put teeth on each side of the fault and have a gear attached to the axle between them. I suppose you could capture the energy with some of those real efficient flywheel storage thingys they have now. As far as the other idea the cable and anchoring doesnt have to be strong enough to withstand the full pull , it just has to be strong enough to lift the weight , or spin the top or whatever - you could put lots of flywheels along the rope and start them like tops.
hen3ry, Apr 22 2004
  

       what if we had a cable from the earth to the moon? That would be something like 2e19 joules per hour if you deaccelerated the moon by 1 m/s every hour
snw, Jun 05 2004
  

       Decelerating the moon seems like a bad plan, living on a gravity well and all.
Salmon v2, Jun 06 2004
  

       More like a gravity dent.
Detly, Jun 06 2004
  


 

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