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GOWTHAM REDDY

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Harvesting electricity from gravity? Is it possible ?

Since I was kid I watched the world around me going through energy crisis. I was wondering if there was a possibility of producing electricity using "GRAVITY" of planet earth.
I was thinking maybe we could use earths magnetic field, and then placing a conductor and oscillating it. when the oscillations are happening there will be potential difference between two ends and E.M.F is induced.
Are there any other ways of using "GRAVITY" to produce electricity ?
If you have any explanations, Ideas or theoretical possibilities please comment below.

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    Nov 28 2012: Gravity is a force. Energy is a force in motion. A falling object produces energy. Rain produces energy. Gravity is the force that propels whatever is falling. Gravity alone is a stagnant force and produces no energy on its own.

    In order to produce electricity, there must be a force in motion behind it. The flow of electricity produces a counter electromotive force. An electric generator requires a prime mover. The more electricity that is drawn from the generator, the more energy the prime mover needs to drive the generator. Energy out can never exceed energy in. That is the fallacy of your suggestion. If an oscillator is used to drive a coil in the earth's magnetic field to produce electricity, it wall always require more power to drive it than the electricity out that can be delivered from the coil.

    In order to utilize energy, there must be a flow of energy. Heat is the principle source of energy flow. The sun is the primary source. It drives hydroelectric systems. It produces the power to drive wind mills because it drives the weather system that produces wind. It can power solar panels. It produced the original energy that went into fossil fuels. It provides the energy of biomass fuels. Fossil fuels and biomass is the sun's energy stored in chemical form.

    Geothermal is a secondary source of heat. It utilizes the earth's internal heat.

    Tidal power is the only power that I know that is produced directly by gravity because it utilizes the moon's gravity to move the tides. But that is because the moon is in motion. The change in gravity is what is creating the energy. There must always be a change and a force driving the change to produce energy.
    • Nov 28 2012: "In order to produce electricity, there must be a force in motion behind it. The flow of electricity produces a counter electromotive force. An electric generator requires a prime mover. The more electricity that is drawn from the generator, the more energy the prime mover needs to drive the generator. Energy out can never exceed energy in. That is the fallacy of your suggestion. If an oscillator is used to drive a coil in the earth's magnetic field to produce electricity, it wall always require more power to drive it than the electricity out that can be delivered from the coil."

      Electrodynamic tethers do generate more energy than is required to put them in orbit, basically they draw energy from slowing down the rotation of the Earth.
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        Nov 28 2012: Interesting reply.

        However, your example uses the inertia of the earth as its energy source. That's one that I didn't consider.
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    Gail . 50+

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    Nov 28 2012: I watched a video recently about how to make electricity using a bicycle. The video then challenged students to create alternative ways to create that energy. One of the things suggested was to use a 2 ton auto jack to life about 500 lbs of weight, and a pulley (plus) system that let the energy be released slowly. The narrator suggest that this will provide about 5 hours of energy before the weight needs to be lifted again - which is easy with a jack.

    Of course, water is the easiest way to use gravity to create energy. That's why we have dams
  • Nov 27 2012: "I was thinking maybe we could use earths magnetic field, and then placing a conductor and oscillating it. when the oscillations are happening there will be potential difference between two ends and E.M.F is induced."

    Yes, this is possible: http://en.wikipedia.org/wiki/Electrodynamic_tether

    "Are there any other ways of using "GRAVITY" to produce electricity?"

    Hydroelectric dams sort of partially harvest energy from gravity, tidal power turbines sort of get all of their power from gravity. Though you always need stuff that was moving in the first place (like the Moon around the Earth), extracting energy from the gravitational field between two objects that are at rest with respect to each other is not possible.
  • Nov 30 2012: cool but insted how about using it in a very nateral way ,, its much easyer than you cud imagin
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    Nov 29 2012: Gravity on its own leads into the 'perpetuum mobile' problem, which can't be solved due to the laws of thermo dynamics.

    And even the earth magnetic field can not be 'harvested' as long as we have no 'point of reference' outside this rotating planet.

    Even Archimedes ones said of his 'law of the lever': 'Give me a place to stand and with a lever I will move the whole world‘.

    Since that time we still haven't found that 'place to stand' but if we would, this was a good point to mount our static coil onto it... :o)
    • Dec 10 2012: "...no 'point of reference' outside..."
      But, as scientists claim that gravity can interact with space (stuff), then we can interact with gravity, tweek it, master it.
      So we find a place outside, set it there, and start generating.
  • Nov 28 2012: Check out "water wheels"


    they are cheep and have been round a Loooong time too!! and then there is the more recent "Tidal action" driven devices
  • Nov 28 2012: Okay John has already noted what came to me when reading Gowtham's comment hydroelectric power is the best example of this.
  • Nov 28 2012: Here’s a way, and its based on gravity. Make a glass cylinder about 10 ft long and make two glass bulbs. Put them at the ends, fill one with water then seal the bulbs to the cylinder so air can flow from one at one end through the tube to the other end without being able to escape. Place a fulcrum at the center. Attach a generator to the center with shaft, then place next to a geothermal hot spring. Gravity will force the bulb filled with water down next to the hot spring, the water will evaporate and the gas will travel to the higher bulb which is in cooler air so the water will condense into the bulb. When enough water is condensed, gravity will force that end down into the spring and the process repeats itself. I imagine this would be a very slow process and would not generate a lot of electricity but hey, maybe a similar concept could be up scaled to make it more than just a fun experiment? Probably the slowest generator ever...of all time.
    • Nov 28 2012: Your contraption would not produce power without the geothermal spring which is the actual energy source.
      • Nov 28 2012: But without gravity the energy that the spring depends on wouldn't exist, since there would be no planet or magma to draw energy from, and gravity itself keeps this process going, however slowly.
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      Dec 5 2012: Google "Minto Wheel". Mother Earth News did an article on a device called a minto wheel. It operates the same way as your example. Their only flaw is that they didn't calculate and provide for "heat out" which resulted in excess temperatures and pressures being built up in the device. Heat out must always balance heat in if the device is to work on a continuous basis.

      Geothermal energy is already being used in electrical generation in Iceland. I don't know if a minto wheel is any more efficient than any other heat engine. That would have to be calculated if it is to have any merit. Its sheer size would most likely be a disadvantage.
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    Nov 27 2012: Use of water falls, and in a way the ocean as well. The basic idea is to use particles physical movement and convert it into electricity. This can also be applied to wind energy, but if you need an energy source the weak thing like gravity would be able to do much. Nuclear and radiation are the best was of attaining energy, in my opinion.
  • Nov 27 2012: Its a good idea, allthough its probably quite costly for its production I believe... im not so sure. But its awesome anyway.
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    Nov 27 2012: Gravity from electricity itself is largely in the realm of perpetual motion (so, no).
    But as already stated, you could harness electricity through other situations effected by gravity such as Dams, and to a lesser extent, friction/motion based energy harnessing.