And no don’t say “cells generate electricity” Yes I know that, but what chemical or whatever process makes it that sunlight is converted to electricity?
I have been wondering this all my life an no matter how much research I do I can’t seem to find the answer, every place just says that some cells inside the panels is what generates electricity, but not how those cells do it
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The thing you’re looking for is photovoltaic effect. It’s a physical process, not chemical. To put it very simply, when different materials absorb light (electromagnetic wave), it adds energy to the particle that “collided” with a photon. Usually this results in added hit. However, in some materials this “collision” can eject an electron out of the atom. When electrons and protons get separated like that, that’s where we get charged particles, and when we get charged particles, we can try to exploit it and generate electricity as they try to rejoin.
It’s due to the **photovoltaic effect.** Certain materials absorb energy from incoming photons, and that extra energy creates a voltage (which is really just a difference in electrical energy between two connected areas).
(Note: this is a very ELI5 explanation, and there are likely a few physicists gritting their teeth at it.)
Imagine two buckets at different height next to each other, with a long ramp going from the upper one to the lower one. The lower bucket is filled with balls (electrons) and you shoot a different type of balls (light) into the bucket. Each collision has some chance to kick a ball into the upper bucket, from there it will use the ramp and end up in the lower bucket again.
The ramp is your electric circuit and the flow of balls is the electric current. The buckets represent different energies the electrons can have in the solar cell.
A solar panel is basically just a reverse LED. An LED creates light by letting electrons flow from a high energy state to a low energy state (through a diode). This process can be reversed. If you strike an LED (or any diode) with a photon, an electron can travel from a low energy state to a high energy state and that energy can be collected by a battery.
Thank you all guys for your responses, you made a girl very happy today, been wondering this all my life, and well, now I know!
When light hits an atom, it can knock free an electron. This electron will push on other free electrons which will push another and another and another. This act of pushing is called **voltage** and the act of motion is **current**. Both, measured together, is **power.**
Plug it into an inverter and you can turn this rudimentary electricity into something useful.
The one thing I would add in particular is that it is the property of the particular material used that results in the suns energy being concentrated into it’s electrons enough to make them jump and cause a current. Other materials don’t produce a notable current because not enough energy will go into there electrons to make them able to leave.
As an added note plants work basically the same way: Cholorphyl is arranged and shaped and composed in such a way that when enough energy from the sun in absorbed into it, it will spontaneously dump that energy into an electron, causing it to escape and jump creating a current that will power various reactions in the plant.
Think of it as a bunch of electrons sitting on the edge of a cliff. In the dark, they all just sit there chilling. When it gets bright and sunny, they get all confused and start wandering around, but the sunlight makes them blind so they fall over the cliff. This makes the current flow.
Light causes electrons to become free to roam with energy in some materials. Solar cells are designed to get these electrons to get to metal efficiently with their energy intact when sunlight hits them.
A solar panel is made of two layers of silicon with small amounts of another element added that make one layer more attractive for electrons than the other.
When an electron is hit by a photon of sunlight, it can get knocked into the less-attractive layer. From there, the electron takes the “path of least resistance” through the circuit the solar cell is powering to get back to the more-attractive layer.
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