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how does a solar panel make electricity
Many people think solar panels turn the sun's heat into power. They don't. They run on light itself, and heat actually weakens them.
Heat is the enemy. A panel rated at half a percent per degree loses a fifth of its power on a sixty-five degree Celsius roof.
So how does light make power? A rooftop panel is sixty silicon cells. Cut one open: a top layer packed with spare electrons, a bottom layer short of them.
Where the layers touch, some electrons spill across and set up a fixed, one-way electric push that points up toward the top layer.
Now a photon of sunlight arrives and knocks an electron loose. The push sweeps it upward, and it can't slip back.
Let's rebuild it whole. A panel is cells, and each cell is two layers of silicon with a one-way push at the border.
Light frees electrons, the push sends them up, and a wire carries them through the lamp and home again. No heat needed.
Stack sixty cells at about half a volt each and you get roughly thirty volts.
Next time you see a roof of panels, remember: they are catching light, and keeping cool helps them.