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Solar Cell connection to DC load

  1. Mar 17, 2008 #1
    Dear all,

    i am possible to do experiment on the application of solar cell and i have run into several problems so i need to seek advice from all the experts in here. I have several DC loads include:
    1 x Cooler fan (12V, 0.25A)
    1 x cooler fan (12V, 0.2A)
    2 x rechargable AA size battery (each 1.2V 0.20mA)
    1 x handphone (the charger of the phone reads output to be DC 5.3V and 0.4mA)

    The spec of the solar.. under sunlight the voltage reading is around 22-23V and current around 0.25A.

    I cut the wire of the charger and attached it to the solar cell and try to charge the phone. The phone reads charging but after 5 secs it says stopped charging. May i know what is wrong? will a DC to DC converter solve this problem? But the best DC to DC converter that i can find from supplier the output is 5V and 1A. Will it still works?

    My next question will be if i will to do connection to the 2 cooler fan, will it be better if i connect it in parallel or series?

    Is it possible to do multiple connections with the above DC loads?

    Do you all think that it will be possible to connect the solar cell in series with any one of the cooler fan, the 2 AA size battery and then to the handphone in series?

    Any recommendations on how should i connect if i want to do multipe connections?

    Thank you for your time in reading my questions and offering your help. So sorry, i lack knowledge in such stuffs but was allocated this project thus very desperate for help with experts in this forums. Thank you so much everyone. Really appreciate it.
  2. jcsd
  3. Mar 17, 2008 #2


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    Science Advisor
    Homework Helper

    I think you need to do a little bit of background reading about voltage and current.
    Try wikipedia.

    I'm surprised you haven't destroyed the phone.
    You will certainly destroy (possibly explode) the AA battery.
  4. Mar 17, 2008 #3
    hmmm.. i tried but i find it hard understanding.. i understand what u mean what u say.. but is there any advice that you can give with regards to my problem?
  5. Mar 17, 2008 #4
    You need to supply your solar panel voltage (23V??) into regulators, which are not 100% efficient, for each voltage that your other devices call for in their spec. Then you use parallel connections from these regulators so that all devices get the same voltage on that node. You must make sure you don't draw more current/power than your solar panels can supply also . .

    If you connect all of the devices in series you're asking for trouble, you gotta use KVL and circuit analysis to understand this. Also, it looks like your solar panels can't supply nearly enough power that you would need to power the devices from the device specs you've given
  6. Mar 17, 2008 #5


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    Staff: Mentor

    The best advice is to STOP doing that, until you do as mgb_phys says, and learn more about voltage and current and power, and other basic concepts. You cannot (and should not) just go cutting wires and splicing things together to see what happens. You could get yourself hurt that way, and you certainly can start a fire that injures others.

    Do some reading at wikipedia.org, and consider getting yourself a beginning textbook in electronics. You can also buy simple electronics kits to help you start to learn the basics of electronics, and to get some relatively safe experience in building your own electronics projects. Like these:

    http://www.transeltech.com/kits/kits1.html [Broken]
    Last edited by a moderator: May 3, 2017
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