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Solar cell

  1. Mar 20, 2010 #1
    I tried connecting my solar cell, 7V/100mA to the ammeter. What I got is 1mA. Why??? The voltage part is 6V, so I assume the efficiency should be at least around 6/7*100 %. But why is it only 1mA? I connected the solar cell straight to the ammeter. I need help fast.

    Thank you.
    Last edited: Mar 20, 2010
  2. jcsd
  3. Mar 20, 2010 #2


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    Staff: Mentor

    You probably just need to put a load on it, otherwise it is just an open circuit. How exactly did you wire it?
  4. Mar 21, 2010 #3


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    Science Advisor

    You will need to get the solar panel in actual sunlight to get a reasonable current out of it.

    If you have the ammeter short circuiting the panel, the current should depend on the brightness of the light hitting it.
    The output voltage would be near zero if you do this, of course.
  5. Mar 23, 2010 #4
    I found out that it is due to the cell not under direct sunlight. Thanks for the help!
  6. Apr 4, 2010 #5
    Keep in mind that it doesn't have to be in direct sunlight. If you ever need to emulate the sun indoors you can always use a Halogen Bulb. A 100W-500W bulb would do the trick. As for the voltage being 6V, it's the property of solar panels to do this. If there is any light available, a voltage is produced first. It takes very little light to produce a voltage across a panel. A solar panel acts more like a current source. The current will vary much more than the voltage itself. Most solar cells are 0.55V (Good ones). The size of the cell itself will determine the current.

    Hope this information is useful for the future. Need more let me know.

    Justin Coulston
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