Solar panel "charging" from LED lighting ????

[Peter1949]

I just noticed something interesting by chance.
I have my solar panel (90W) in an aluminum frame lying facing up on my worktable in my little workshop waiting to be put out in the sun when we get some.
When I switch on the internal LED lights the solar controller turns green indicating a charge being received from the panel.

Any idea what kind of charge that would be ? I thought they only worked on daylight.
If I switch the lights off and the panel in the same position even in daylight (cloudy) it does not charge.

[ekkekan]

Peter I would say the LED lights emits a wavelength of light to increase the voltage of the panel cells enough for the controller to see enough volts and then turns on. I would guess there will be very little current to do any charging.The voltage of the panel would also be very low.

[Peter1949]

I suspected as much, I was just surprised, I thought it needed natural outdoor light to function at all.
Makes me think though, would it be worth putting the panel inside where lights are on anyway on cloudy days to get at least some charge to my backup batteries when mains power is ON ?

[Oppies3800]

I suspected as much, I was just surprised, I thought it needed natural outdoor light to function at all.
Makes me think though, would it be worth putting the panel inside where lights are on anyway on cloudy days to get at least some charge to my backup batteries when mains power is ON ?

I suspect for the effort it won't be worth it

[Spiceman]

I suspected as much, I was just surprised, I thought it needed natural outdoor light to function at all.
Makes me think though, would it be worth putting the panel inside where lights are on anyway on cloudy days to get at least some charge to my backup batteries when mains power is ON ?

If I were you I would still do it and measure it or test it to get some concrete data.

[Viertrek]

In the big caves open to tourists like Cango and Sudwala, they noted green plants starting to grow close to the lights deep inside the caves.

So it seams like light is light, no matter if it is natural or "artificial".

[bigboy529]

Sometimes at night when conditions are just right, you can even see a voltage rise on panels due to the moon and stars, but it's negligible, hardly anything to write home about.

[ekkekan]

I suspect for the effort it won't be worth it

Yes I agree. The voltage to wake the controller might be very low - 3 to 5V. This will not even charge a cell phone due to no current.

Filament bulbs do provide more light in the right spectrum than LED. Easy to check by measuring the voltage with LED and then putting it in front of an older car headlights that don't use LED.

[Peter1949]

Yes I agree. The voltage to wake the controller might be very low - 3 to 5V. This will not even charge a cell phone due to no current.

Filament bulbs do provide more light in the right spectrum than LED. Easy to check by measuring the voltage with LED and then putting it in front of an older car headlights that don't use LED.

Interesting, but then those old incandescent lights wasted just so much power in heat.
The LED's a bit less.

I was just surprised and wondered about it.
Thank you all for the feedback on this - just a matter of interest - not anything really practical methinks.