Eli5 – How does solar power actually work?
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It’s called the “photoelectric effect” and it’s what Einstein got his Nobel Prize for, not the famous E=mc^(2).
Light is made of little balls of energy called photons. When photons hit materials, if they have enough energy they can knock electrons loose from the material and send them flying. “Moving electrons that have energy” is just another term for electricity. The solar panels are made of materials that readily get their electrons knocked loose by the incoming photons in sunlight, sending the electrons off down a wire. The energy in the light is converted to the energy of moving electons.
In general, sunlight is a form of energy, so you collect the energy, convert it to a useful form, and there you go.
The specifics of how it actually works depends on the type of solar power you’re talking about. If you’re using solar power to provide light, then the technology can be as simple as a skylight. If you want heat, then you can concentrate the sunshine using parabolic mirrors or magnifying glasses. Usually you would focus the sunlight on black pipes which contain water. The water gets hot and is pumped (sometimes passively) to where it is needed. The bigger the surface area, the more heat is collected. Some places use intense solar power to destroy toxic waste.
If you want electricity, you could use the heat gathering techniques described above to boil water, make steam, and turn turbines linked to generators. Or you could use solar-electric cells.
Solar cells work by the photons in the sunlight imparting enough energy to a semiconductor material to knock an electron loose from its “home” atom. The electrons so loosened repel each other, and push each other down the wire to the load. They then return via the other wire, to the dark side of the cell.
Solar panel cell is basically a led light in reverse. Its a property of all NP diodes. Over the junction there is a voltage drop, in a normal diode operation electrons can drop down that voltage gradient but how to get back up? Thats why diode only conducts one way. But when a charge drops down a potential, energy is lost, so where does that go? Its emitted as photon, thus LEDs. Reversing the process a photon can pump the electron up that voltage barrier and that way you get a solar panel.
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