Why doesn't photo voltaic cells erode ?

Discussion in 'General Electronics Chat' started by Michael George, Mar 26, 2015.

  1. Michael George

    Thread Starter Member

    Feb 8, 2015
    I've read about photo voltaic cells which converts the solar energy into electrical power. I find out that when they receive photons (light), the electrons of a photo voltaic cell are able to move freely and produce electrical current. I know that any material consists of electrons, protons, and neutrons. So I imagine that .. when electrons leave a photo voltaic cell, It should have less mass and it should start to erode or to be ionized and converted into another material. Am I right ? If no, how photo voltaic cell recover the loss of electrons ? I don't think photons of sun light replace the electrons !! because they just motivate electrons to move freely by giving them some energy. I also, thought the same Idea about piezoelectric material. when we give it a mechanical energy , it produces electrical current. does that mean it will erode ?
  2. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
    Look at it like an electric generator or even an in-line water pump. What goes out is returned. The generator, PV cell, or water pump just provide motive force. There s no net loss of electrons.

    This reference is a little more detailed: http://org.ntnu.no/solarcells/pages/Chap.4.php

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  3. upand_at_them

    Active Member

    May 15, 2010
    Don't think of the PV as a finite source of electrons. Think of it as a facilitator of electrons.
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  4. crutschow


    Mar 14, 2008
    A PV cell generates an EMF to move the electrons from the positive to negative side of the cell in a continuous stream through a conductor connecting the two sides.
    There is no net loss or gain of electrons.
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  5. Papabravo


    Feb 24, 2006
    It also takes 1837 electrons to equal the mass of one proton.
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  6. JDT

    Well-Known Member

    Feb 12, 2009
    But the charge is the same (but opposite).

    A current of 1A is 1 Coulomb (of charge) per second. A coulomb is 6.241509×10^18 electrons.

    Just thought you would like to know that!
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