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Capacitor and capacitance

  1. Nov 12, 2011 #1
    What is the highest capacitance ever made/achieved?

    I am asking this because, when I am solving some time domain circuits, the values are given like 3 F etc. And I know that is absurd, and I really hate it because, if I didn't take electronics at home, I wouldn't have the feeling for high/low capacitance.

    But anyway, what is the highest capacitance ever recorded?
     
  2. jcsd
  3. Nov 12, 2011 #2
    Achieved by the Nature, probably, recorded by the Brazilians, most probably - in the Amazonia regions.
     
  4. Nov 12, 2011 #3
    That capacitance is?
     
  5. Nov 12, 2011 #4
    If you google "5000 Farad capacitor" you'll see that there are several companies selling capacitors of that capacitance. So 3 Farads is not a ridiculous number.
     
  6. Nov 12, 2011 #5
    omg. You can store a power plant in it?!?!? :D
     
  7. Nov 12, 2011 #6
    Yeeeaaaah, I guess 5000 F is pretty ridiculously large. Considering that if you hooked it up to a single volt of power, you'd get 5000 C ... Which, discharging in 1 second, would give you 5000 W. Nbd.
     
  8. Nov 12, 2011 #7
    5kW ?!?!? Thats like freakin' 5 washing mashines :rofl:
     
  9. Nov 12, 2011 #8
    http://powerelectronics.com/passive_components_packaging_interconnects/capacitors/1000-3000-5000-farad-ultracapacitors-031810/" [Broken] of the place that sells 5000 F capacitors. It says they're for "A wide range of high-power applications, such as transportation, electric utility, material handling, industrial bridge power and renewable energy generation."

    ... so they could very well be powering 100 washing machines with that capacitor. :)
    Although, keep in mind that it's only 5 kW if it discharges in 1 second. That's apparently not the intent, since the site also says they're for "long-operating-life energy storage."
     
    Last edited by a moderator: May 5, 2017
  10. Nov 12, 2011 #9
    If you are taking in washing now I have some available!

    :rofl:

    Meanwhile ask yourself what is the capacitance of a 200 amp hour 24 volt lorry battery?
     
  11. Nov 12, 2011 #10
    Well, using my prestigious knowledge of physics, and quantum mechanics, taking in the Schroedinger's wave equation, adding in the spin of the electrons, shape of the battery is approximately cylindric...

    My final answer is I am clueless :rofl:
     
  12. Nov 12, 2011 #11
    But still what is the capacitance of that lorry battery? Must be huge.
     
  13. Nov 12, 2011 #12
    Sparkfun sells a 2.5V 10F "super capacitor", so it's possible even with small electronics components.

    http://www.sparkfun.com/products/746

    You not likely to ever use something like that except in specific applications though, I imagine.
     
  14. Nov 12, 2011 #13
    Gotta admit, I learned a lot of stuff through these forums... A LOT
     
  15. Nov 12, 2011 #14
    Here's a clue

    200 amps for 1 hour = 200 * 3600 amp-seconds = 200 * 3600 coulombs

    Capacitance = Q/V
     
  16. Nov 12, 2011 #15
    30 000 farads ?!?!?

    Why aren't we taught this example? :D

    But there has to be a catch. These coulombs will released slowly right? Opposing to that 5000 in one sec?
     
    Last edited: Nov 12, 2011
  17. Nov 12, 2011 #16
    Batteries don't have capacitance.

    They have capacity, but not capacitance.
     
  18. Nov 13, 2011 #17
    BTW, the capacitance of thunder clouds is very small - contrary to what I have thought.
     
    Last edited: Nov 13, 2011
  19. Nov 13, 2011 #18
    in curcuiit theory an ideal battery is equally modeled as a capacitor of infinite capacitance.
     
  20. Nov 13, 2011 #19
    Yea my bad.
     
  21. Nov 13, 2011 #20
    Studiot's calculation is still meaningless.

    Batteries aren't capacitors.
     
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