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My road-bed gravity generator: new look!

  1. Jun 30, 2004 #1
    My road-bed gravity elec. generator: new look!

    How about this? Escavate 100 meters of interstate road-bed to about 8ft. Span it with a flexible "bridge" that sits on cylindrical columns that inbed into cylindrical water tanks. The bridge will have its own "spring," but springs beneath it will fix it at its base-line shape. As cars and semi's pass over it, it compresses the water in the cylinders that carry small hydraulic lines out to many generators. The pressure would depend on the size of the installation, road traffic and the properties of the bridge, but it could be many thousands of pounds. When the weight applied by the passing vehicles decreases, the springs force the bridge back to original shape. Some of this force could be used for refilling the cylinders as the span rises driving the generators through a second feed. :grumpy: We are robbing Peter to pay Paul, but you are really just driving through a long dip in the road that would not be noticable at 100 pluss meters span. The generators could send electricity out, or charge a battery array. Please help me improve on this idea if possible. Thank you.

    Last edited: Jun 30, 2004
  2. jcsd
  3. Jul 1, 2004 #2
    This sounds like the roadway will bow under the weight of the vehicle, creating a dip that will have to be climbed out of. Additional work would need to be performed by the vehicle engine. To me it sounds like driving in sand.
  4. Jul 1, 2004 #3
    gas prices are high enough, don't make me come hurt you cause of your creating ditches i have to waste fuel to drive out of... :mad:

    cute idea though :wink: i rate it about 8.7 on the ingenuity scale
  5. Jul 2, 2004 #4
    Thank you for your responses! Please help me to develop this idea further. Depending on the materials and properties of the "bridge" system, maybe these weaknesses can be reduced. The system could be installed on a downhill slope, thereby recouping some of the energy used when the vehicle climbed the hill. Your points helped me think that up. Thanks!
    Also, iif it were 200meters or more, it could employ more support "plungers" and only have to dip 1/2 meter or so. This would not be noticeable.
    Any other ideas. There is a website about a guy who has actually patented and started a business employing fluid filled containers that vehicles drive over, forcing the fluid out and through a generator. I don't believe that his idea could ever be popular.
    I want this idea, our idea, to be a group effort. The stakes are too high to be self-interested.
    Last edited: Jul 2, 2004
  6. Jul 2, 2004 #5


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    How about little hyraulic pumps in the heels of peoples shoes. Since people need cushioning in their shoes anyway, it would not be wasteful. The pumps could charge batteries. The power generated might equal the power used to manufacture the rechargeable battery!

  7. Jul 2, 2004 #6
    Your shoe electric generator sounds O.k. to me! Wearable computers could be run/recharged by such a device.
    I have an improvement already to our road bed generator. It will be on a two lane interstate feeding, or leaving a large city. It will be a ridged bridge that is hindged at the top of a hill and extend to the bottom where a free moving end will leave the vehicles back onto the normal road surface. This design is a lever. By being ridged, it can be built out of pre-fabricated bridge components that are standardized, available and cheaper than anything made out of scrap.
    So, after topping the hill, the vehicle rides onto the surface will little more than a clicking sound coming from the tires. As it decends, the force produced at the top and underneath the bridge increases. Giant plungers bear down onto the water in the cylinders and run the generators.
    "Its alive!!"
    The design of the spring system underneath and the system as a whole capitalizes, not on the amount of weight on its surface, but on the variation in weight as vehicles if different numbers get on and off. The turbines run on both the compression and decompression cycles of the system.
    So, the flexible (and expensive) bridge surface is out and a ridged "pump handle" system is in.
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