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Solar cells(volts,watts & amps)

Solar cells(volts,watts & amps)

Solar cells(volts,watts & amps)

(OP)
Hi all,
   I want to build my own solar panels but keep coming up with one problem.  From what I've seen the average quality solar cell produces .57volts @ 2.0amps(give or take).  Most Pre-built solar panels have 36 cells(4columns and 9rows) and produce 17volts with a wattage of 50-100.  My question is, how do you wire them to produce those numbers?

         Thanks much

RE: Solar cells(volts,watts & amps)

The power of a solar module is calculated as below P= I(current) x V (voltage)

If each cell produces 1/2 volt @2.0 Amps the power of each cell is roughly 1 Watt.
So a 36 cell panel will produce about 36 Watts,  but realistically around 30W, after losses and so forth.  So I do not understand where you received those high  numbers.  It might be possible that they are peak power numbers and not average.

In addition you can wire each string (4 strings altogether) in series.  Then you can wire the strings in a combination of series and parallel to get different amperages out. If you wire in parallel the amps will be higher and the voltages lower and if you wire in series, vice versa.

Hope this helps!!!

RE: Solar cells(volts,watts & amps)

ANYONE CAN HELP?
DOING A THESIS IN SOLAR ENERGY AND CIVIL ENGINEERING BUILDINGS!
HELP!
xbesty@hotmail.com

RE: Solar cells(volts,watts & amps)

If you connect them all in series you will get 36 * 0.57 volt = 17 volt

RE: Solar cells(volts,watts & amps)

HERE'S A TIP:

DOESN'T IT FEEL LIKE I'M YELLING AT YOU?

People will be much more responsive if you use capitalization properly.

Good luck.

RE: Solar cells(volts,watts & amps)

Mr Bean: The rules of arithmetics wont change
independently how you connect them .

36* .47 = 17

<nbucska@pcperipherals.com>

RE: Solar cells(volts,watts & amps)

I suspect an explanation of the rating would be something like this:

36 * .57 = 20.52 volts.  This would be the expected open-circuit voltage of the solar cell with no load attached.

Each cell will have an internal resistance (also known as the Thevenin equivalent resistance or source resistance).  If we assume that the assoicated drop from 20.52 to 17.00 = 3.52 volts comes at maximum load of 2 amps, then the internal resistance is 3.52/2 = 1.76 ohms, or 1.76/36 = .05 ohms per cell, which sounds reasonable.

The same thing happens with any electrical source.  A good example is your car battery.  At open circuit, it may read 13 to 14 v.  Under normal loads, it will drop to about 12.  Under engine starting, it could drop very low, possibly in the range of 6 to 10 v.  This is all due to the internal resistance.

RE: Solar cells(volts,watts & amps)

its fun working with solar cells, i made a solar walkman myself, with blocking diode to prevent reverse flow of current, you just remmember that, 1amp=1000 milliamps, volt x amps = watt,

RE: Solar cells(volts,watts & amps)

Hi network

to go higher watt 50W  of same configuration.  you may have to increase your cell size to get higher higher watt or your have to increase your number of cells. Cells configuration(parallel or series) depends on your requirement.  If you need 12V, you may have to connect around 20 cell in series.  Here current rating depends on the minimum current in the series of these 20 cells.  each row you have make 20 cell and increase your column depending on current requirement and connect in parallel.


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