From
Scientific American"How does a solar cell turn sunlight into electricity?
In a crystal, the bonds [between silicon atoms] are made of electrons that are shared between all of the atoms of the crystal. The light gets absorbed, and one of the electrons that's in one of the bonds gets excited up to a higher energy level and can move around more freely than when it was bound. That electron can then move around the crystal freely, and we can get a current.
Imagine that you have a ledge, like a shelf on the wall, and you take a ball and you throw it up on that ledge. That's like promoting an electron to a higher energy level, and it can't fall down. A photon [packet of light energy] comes in, and it bumps up the electron onto the ledge [representing the higher energy level] and it stays there until we can come and collect the energy [by using the electricity]."
There are other articles that discuss the different materials in use like Gallium-selenide, Indium, and the mix of each to harvest power at the "junction" of the solar cell.
To theorize about the thermodynamic aspects of a module, you'd have to know the available photon makeup and transfer characteristics of the silicone, things that are way beyond my paygrade.
