Friday, April 24, 2015

Solar Power on a Cloudy Day



Yet another rainy morning prompted C (age 8) to ask if we could power our solar panel with a candle.  My first reaction was to say no - it's not the right type of light, the rays, or the wavelengths, or something would be wrong.

But, of course, we tried it anyway.  And, it turns out I was wrong.


You can generate power from a solar panel, with a candle.  The light from one candle produced enough power to run our smallest hobby motor.  More candles made it run faster...


...but did not give us enough power to run our normal sized little hobby motor. 


We could also get enough power for our small motor from an LED flashlight...


...and lamp.


And again, the closer the solar panel was to the light source, the faster the motor would spin.


If I understand correctly, solar panels work when photons from the light (apparently any light, as long as it's strong enough) hit and knock electrons out of place on the semi-conductive surface (usually silicon) of the panel.  Electrons move to fill in the space, creating an electric current...


...even on a cloudy day.

4 comments:

Lucinda @ NavigatingByJoy.com said...

I can't tell you how much I've enjoyed learning about solar power with you guys this week.

You have a real talent for expressing complex scientific concepts in easy-to-understand ways. And who knew you could power solar panels with birthday candles?! Perhaps solar panels should more accurately described as ... um... photo panels...? Or is that something completely different?! (Reluctantly tears self away from web search for appropriate adjective...)

Ticia said...

So you can artificially create it with another light source, but if you were really using solar power (like a power station) then no that doesn't work.

Angelic Scalliwags said...

Well, I've learnt something new today! Who knew?
I've enjoyed the depth with which you've studied solar power.

maryanne @ mama smiles said...

Very cool! I knew you could use lamps (from experimenting as a kid with a solar-powered calculator), but never would have thought to try candles!