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Electricity generation through crystals

  1. May 4, 2007 #1

    You can be sure that the method that i'm going to propose is of no commercial significance. Anyway, I'd like to know why.

    Set up(regardless of dimensions):-

    place two permanent magnets with like their like poles closest to each other in a linear tube and at the end of the tube, place piezoelectric crystals.

    As the magnets push, ions begin to flow in the crystals thereby producing electricity.

    Possible reasons for failure( i'm just guessing):-

    the electricity produced will be of such negligible magnitude that it'll only qualify to be called an "electric pulse".

    Actually, i'd be surprised if one can make a small decoration bulb glow for even a few seconds with this method because(correct me if i'm wrong) any power output would defy the basic law of conservation of energy.

  2. jcsd
  3. May 4, 2007 #2
    You are right when you say that you will not beat the law of conservation of energy.

    Generation of electricity by piezoelectricity has been used for years, but not for power generation. It was used in turntables cartridges and in microphones. It is also being used is gas lighters and other marginal applications.
    Piezoelectric materials generate electricity when the dimensions are forced to change under stress. But just during the change.

    I saw, longtime ago, a physics demonstration device with a piezoelectric crystal (Rochelle salt) and a neon bulb. It lightened when you hit the crystal. It does not lit for seconds, but just a flash.

    Your magnets are inutile.
  4. May 4, 2007 #3


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    Piezoelectricity will not produce a continuous flow of electricity through that method.
  5. May 4, 2007 #4
    Very true.

    Actually, when i was thirteen, i thought that i had stumbled upon a mechanism to defy the basic law of conservation of energy that would also revolutionize the world. I thought that if we could replace electro-magnets with permanent magnets inside fans and motors, we'll have eternal-spinning motors that we can use in automobile and other applications. After a few years, i learnt that "change" in electric flux brings about the generations of electricity not merely its existence.

    And the case here isn't very dissimilar i guess. Probably we can achieve continous glow if we can vary the magnitude of repulsion between the magnets; and to do this, we need electro magnets. Simultaneously, this will solve the case of the undeniable basic law too.

    I have a few questions:-

    Can anybody give me the figures for the magnitude of the electric pulse that can be produced using crystals?

    What is the physical set-up that would harness/embed information from/in the moving ions inside the crystal?(in case of the microphones etc.) [ At the sub-atomic level]
    Last edited: May 4, 2007
  6. May 4, 2007 #5
    You could achieve continuous glow if you apply an alternative force on the piezoelectric material. The voltage produced will be alternative. If the frequency is high enough (more than 20Hz) you will see a continuous glow.
    Magnets are inutile. Piezoelectricity has no link with magnetism.

    In gas lighters you obtain several thousand volts (2-5 kV) and currents of the other of 1 mA (very short in duration).
    It is very unpleasant to touch the spark point.

    You do not have access to any information about atoms in the crystal. A piezoelectric crystal produces a hight electric field as a drum produces sound when you hit it.
    There are not moving ions in the crystal. Each atom stays at the same place a keeps the same neighbors. Just the whole crystal is deformed by the stress, when you hit it.
  7. May 4, 2007 #6


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    You need an oscillation, to be more precise.
  8. May 4, 2007 #7
    This is how i imagine it(enrich me if i sound naive):-

    When you speak in front of the mic, the vibrating air molecules transfer the information of their frequency, pitch, amplitude etc., to the crystal(by hitting them) where it gets translated to electric pulses in which the info on the varuious natures of the input sound is embedded. At the end of the circuit, you need the decoder i.e. a device that reads the electric pulses and retranslates it into the original form i.e. sound again. Also not that the device doesn't merely convert the data to original format but also lets modification (amplification etc.,) which proves that the decoder can actually discern the different natures of the input sound.

    If this explanation is correct,then what i don't understand is how exactly does it get embedded, preserved and retrieved?( the sub-atomic mechanisms) If we can understand that, we can simply create the electric pulse (in our labs without using the crystal or the input sound)to get the desired output from the decoder. Get it?

    Of the information( from secondary school) that i have about the atomic structure, i cannot percieve how data gets translated from one physical medium to another meduium(at the sub-atomic level) at all!

    P.S. - May be i should get some help from textbooks on solids and semiconductor devices.
  9. May 4, 2007 #8


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  10. May 4, 2007 #9
    This is almost correct. The sounds in air consist in variations of pressure. When the sound arrives to a piezoelectric microphone, the pressure variations deform the crystal and a variable voltage appears in the electrodes (metallic parts placed against the crystal). This voltage is proportional to the deformations (its time derivative if you want to be precise). Thus it has the same frequency and an amplitude that proportional to the sound amplitude and which depends on the frequency of the sound.
    The sound is not "coded" as in a CD. It is "in clear" and if you amplify this voltage and feed directly a loudspeaker you will hear the original sound. You do not need a decoder. It is not data in the modern meaning of the word (numerical data).
    This situation is the same that you had with classical vinyl records and even on Edison rolls and his gramophone. Information where recorded in analogical way. It was not coded. In fact it has no link with atomic structure.
  11. May 5, 2007 #10

    Thanks. That helped a great deal.

  12. Jun 28, 2009 #11
    I came across this discussion topic while seraching for "electricity through crytals"

    So to generate electrical useuable power we ned the crytals als transformators.
    They are to be used as transormators that use high order frequencies.
    So waht kinf of setup is needet to attract the kind of energy that can be transformed in crystals to a energy that we can use to run machines we need?
    Maybee magnets are a solution. Magnetic fields are not completly undrestood, close to gravitiy?
    So there is a missing aspect that humanity does not know yet. Maybe that there lies our next step in evolution. Do understand the nature of gravity and magnetism to then be able to buila a highfrequency resonator that vibrations then can be transformed by a crystal to a electrical powersource.
    The vision of such an aparatus appeared allready and was shown in sci-films. The existence of such a vision is the prove that it is possible.
    See the Comunicators from the TV series now we have mobiles....

    Is anyone working in the field of building highfrequencie resonators?
    can vogle crystals be a link?

    Greets Gy
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