howardwheeler wrote:
Very informative. Does the panel, then, actually become slightly cooler when the "valve" is open, that is, when the circuit closes? If this sounds stupid it's only because in the fundamentals of electricity I am stupid.
Think "energy" instead of "power." It is all about conversion of energy. Your rock on the edge of a cliff vs the rock falling and hitting something, and all that.
The panel heats up in the sun same as anything else dark in colour, whether it is connected or not.
I don't know if when it is "running" it heats up any from that too, but you won't see any reduction in panel heat you can measure because I ASSume the sun heating is so much greater than any heating from the panel "running."
I have measured the tilted panel temp from behind it with my IR gizmo and found the temp varies across the panel and up and down it too. You have to pick a spot and use that each time to get your panel temp for comparisons. Be difficult to figure how much heat is from what.
However your electric energy is not coming from conversion of the panel heat energy as such. It comes from the way the cell is built more of a chemical energy thing set off by sunlight. The sunlight radiation energy that sets off the cells is not the same thing as the sun making the panel "hot in the sun" --but I am not too clear on that!
The joke is that when the panel heats up, it "makes" less electric power when it is connected than when it is colder and connected.
So the best thing is to lie down until the urge to figure this out goes away.
