| MadSci Network: Physics |
Reply:
> Would a solid red light source or a solid green light source
> produce produce more or less voltage output, than white light?
The power produced by a solar cell is dependent on the color of light striking it, yes. There is a "responsivity curve" which tells how good the solar cell (of a particular type) is at collecting photons of various wavelengths. Solar cells made of silicon, for example, are best at collecting red photons.
Since photons of different colors have different energies, however, the story is a bit more complicated than this, and in order to be fair, you have to put as much power in the solid red or green test light sources as you put in the white light source.
Another complication, the way you worded the question, is that in solar cells, the produced voltage stays constant (presuming the photon has enough energy to propel electrons over the energy bandgap in the silicon crystal to make the solar cell work). What changes is the amount of current that the cell produces, but the idea is the same.
-Greg Billock
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