Solar panel

Hi,

I have a solar panel which generates a max of 2W out.

Would it be possible to trickle chargle batteries of a higher voltage?

I have a high voltage battery (12VDC...ok not that high) running many
smaller low voltage LED's. As the LED's dont use much energy, Im assuming
that a small solar panel can put back what the LED's took out.

If this is possible, do I need any extra's to hook it up besides a diode?
Also, does voltage or current play a role in my answer?

 

Yes Vincent
The voltage output is very important and your question cannot be answered
without clairvoyance ;_)
You will have to find out the voltage (output by the panel) by measurement
or a nameplate etc.
To charge the 12v battery it would want to be at least 14v output.

 

That violates the conservation of energy principle, you can't run LEDs
off a battery and recharge that battery with a solar panel powered by
the LEDs. LEDs are at most 40% efficient at converting power to light,
solar panels are %20 (not sure) and you lose even more power in the
battery. An LED array takes a lot of power more than just several
watts.

 

Would it be possible to trickle chargle batteries of a higher voltage?
====================================================
There are very efficient (80 to 90%!) dc to dc converters that accept
input volts over a 4:1 range 9 to 36 volts. A 12V solar panel is
typically 21V and 0 ma or 0V at 320ma or somewhere in between like
12v and 160ma. or 14V and 130ma (about 2 watts). Check out electronics
places like Jameco, Digikey to look for dc to dc converters and power
supplies.

 

Yes. A boost converter can increase the voltage. What voltage does
your solar panel produce?

It depends on how much current the LEDs use. "Many" LEDs could mean
5 or 500 or ?? If the LEDs take out less than 2 watts and the panel
produces 2 watts then (ignoring losses) your panel can put back in
what the LEDs took out.

Yes and yes. You'll need a DC-DC converter to raise the voltage
to the voltage needed for trickle charge - and you need to know
how much current the LEDs use to decide whether the project is
worthwhile.

Ed

 

Nobody metioned power yet. Red blue and green leds have diff
voltages... but .02amps and 3v will run one...thats .06watts, so a
2watt panel will run 33 leds.