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Electro Gravity Tiles - generating electricity from moving vehicles

  1. Jul 12, 2008 #1

    Ouabache

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    Using electro gravity tiles, there is an emerging technology that can generate electricity from moving vehicles. If we continue to populate the highways and roads, we might as well extract energy from their motion. How cool is that? :tongue:
     
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  3. Jul 12, 2008 #2

    Gokul43201

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    This thread belongs in the Debunking Product Claims forum. What a joke that video is!
     
  4. Jul 12, 2008 #3

    Ivan Seeking

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    This is completely bogus. The energy from the tiles comes from petroleum powering the cars. It would be an extremely inefficient means of converting petro energy to electrical energy.
     
  5. Jul 12, 2008 #4

    Ivan Seeking

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    Gokul, you got me on this one. This is not an advertised product or an unexplained phenomena, so technically it doesn't belong in S&D, but I won't bother moving it back now.
     
  6. Jul 12, 2008 #5
    But it's not meant to do that. It's meant to save unused energy. Independently of whether it actually works of course.
     
  7. Jul 12, 2008 #6

    Ivan Seeking

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    Technically, the first tile encountered might. :biggrin:

    Oh wait, these probably stand above the road surface, so I guess not.
     
  8. Jul 12, 2008 #7
    :rolleyes:
    So, technically, would the number of miles per gallon increase ? (one cubic milliter per light year counts)
     
  9. Jul 12, 2008 #8

    LowlyPion

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    It's not completely bogus. Certainly I agree that it is bogus for cars if the idea is to convert horsepower from gasoline into stored energy in the tiles, even if going only down hill, but I rather think there are other applications.

    For instance if you installed something similar on descending stairs, such that each down step captured some of the pedestrian traffic that should be a net gain. For going upstairs of course it would seem to be be an increased effort, but would people notice? If you steal power from people effort, that's more calories used, that might mean healthier public?
     
  10. Jul 12, 2008 #9

    Ivan Seeking

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    The idea of power sidewalks has been around for decades, but that isn't what we are talking about. This idea is bogus because the source of the energy is petroleum.

    I assume that power sidewalks and stairs make no sense as the cost, perhaps in both energy and dollars, would exceed the returns.
     
  11. Jul 12, 2008 #10
    But no, really, it is the movement of the cars and trucks, which could be powered by... electricity ! At least in principle. Of course it has a very low efficiency, but the idea would be to use what is not at all for now. The numbers are very suspicious though. In particular, the question would be "how much would that cost compared to other means of producing (sustainable, free) electricity".
     
  12. Jul 12, 2008 #11

    Ivan Seeking

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    I was saying that we might net a little energy from the road for a millisecond, but only until we had to climb out of the hole from the first dot.
     
  13. Jul 12, 2008 #12
    We put an accelerometer in a box once, which we were shipping overseas. For insurance purposes. I was amazed by the values which can be reached in a truck, much more than what can be reached in a plane for instance. Those are up-down accelerations. This is completely useless as of today. They are very short excursions, and could not generate much power, I do not believe the numbers in the video. But technically, there is a non-zero effect. Of I may be out of my mind today... :smile:
     
  14. Jul 12, 2008 #13

    Ivan Seeking

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    I see what you are saying: I think that is a different situation from inducing vertical accelerations, but we are already wasting energy as heat in shock absorbers.

    I wonder if linear generators could be used as shock absorbers in electric cars, and what would be the returns? As you said, probably too small to even consider, but I have never even looked at that one.
     
  15. Jul 13, 2008 #14

    russ_watters

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    So... you'd power an electric generator with an electric motor powered by an electric generator?

    It seems like you may be missing the point here:
    It has negative efficiency.
    The only unused energy in a car driving down a road is in the gas tank. Attaching a power generating device to the road therefore requires burning more gas.
     
  16. Jul 13, 2008 #15

    russ_watters

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    That isn't what is being claimed in the video, but I agree: the amount of energy dissipated in shocks is extremely small. There is a reason you don't see heat sinks bristling the sides of a shock absorber.
     
  17. Jul 13, 2008 #16
    Well it is far from being trivially as clear as you seem to suggest !

    Take a fat trucker, you will not tell me that a bump on the road can not generate accelerations of the order of a few g, proof is as simple as him jumping from his seat now and then. Attach some kind of electrical generator to him, and you will definitely get some power out of it. Certainly not enough to light a bulb, but in principle at least it works, and in that case I do not think it affects the amount of gas burnt by the engine, at most it makes the trucker jump less high.

    Therefore, I imagine it possible indeed to use the same kind of generator to the road, possibly not affecting the gas at all, but reducing the stress in the shock absorbers for instance, as Ivan mentioned.

    As I said before, I have put an accelerometer in a truck, so I have measured those vertical accelerations, I am aware they are very short, but I was amazed how high they can reach.

    Finally, I mentioned the fact that the whole thing would probably affect the number of miles per gallons (said "increase" instead of decreased BTW). I just can not provide actual numbers, and that was all just merely out of fun if you really read what we've been exchanging here.

    edit
    I did not see your second post before I started this one :redface:
     
    Last edited: Jul 13, 2008
  18. Jul 13, 2008 #17
    Take an individual car. Less than 10% accelerates the car, and approximately 1% of the gas is used to move the people in it. There are losses all over the place.

    Amory Lovins @ TED
     
  19. Jul 13, 2008 #18

    russ_watters

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    The video is so bad, it is tough to even detect coherent thoughts (they mix energy and momentum, for example). But they did make one specific claim: the total energy available in moving cars. A quick google shows the US uses 40 billion gallons of gas a day or 14.6 trillion a year. A gallon of gas contains 36 kWh, so that's 530 billion kWh per year. That's "of the order" of what they claimed the energy available was.
    No one said it couldn't generate any power, we just said it can't generate a significant amount of power.
    No. What you are suggesting doesn't work the way you are suggesting. The purpose of shock absorbers is to absorb energy caused by bumpy roads. If a road is perfectly smooth, you don't need shock absorbers and no energy is wasted there and your fuel usage goes down. Blanket the roads with a material that is soft enough to deform and generate electricity, and the energy expended by the engine again has to increase to compensate. It would be like driving your car through jello.
     
  20. Jul 13, 2008 #19

    russ_watters

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    I didn't say "lost" I said "unused'. Energy that has been lost has been used -- just not used for what you are trying to accomplish.
     
  21. Jul 13, 2008 #20
    Oh I absolutely agree about (against) the video and their claims, although I was unaware of the numbers (36 kWh is a very useful number to remember !).
    I see, and again completely agree with your points. I indeed assumed that the material would not be any smoother than an actual road. It is clear for everybody that the output would certainly be negligible, but most importantly, in any case (whatever the power available) it would probably be best to use "clever" shock absorbers as Ivan suggested.

    Thank you for the comments.
     
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