How Do Solar Panels Work?

In order to understand how solar panels work, you have to understand, on a basic level, what electricity is. Very basically, electricity is the movement of electrons. So, a solar panel uses the photons raining down on us from the sun to move electrons in a way that we can use them to do cool things like power light bulbs, open automatic doors and look at funny pictures of cats on the Internet. Now, onto the science!

The base chemical in a solar panel is Silicon. Silicon by itself is a very inert substance. Silicon shares electrons with itself very well, perfectly in fact, and does not like to give them up. This is why we use them so frequently in computers. However, if you bring something into the mix, like Boron or Phosphorus, well that is a different deal.

When Phosphorus shares with Silicon, it is very unstable. There is an extra electron floating between the two (Phosphorus has 5 electrons, where Silicon can only use 4 of them). This means that the Phosphorus/Silicon substance would be very happy to give up that electron. Long story short, when a thin layer of Phosphorus and Silicon gets hit with a photon, that extra electron really wants to move.

The problem, then, is finding a place for this electron to go. Well, in a solar panel there is another layer, a layer of Silicon and Boron. Boron only has 3 electrons, meaning that the Silicon, who likes to take 4, is looking to take in another one. Do you see where this is going? The photon knocks off the electron, which then goes to the Boron/Silicon layer. It is this differential that causes an electric charge.

This charge is often all over the place, depending on the time of day and the condition in the sun. The charge flows to an inverter, which converts all of the electricity to a standard voltage. And that, dear reader, is how we get electricity from the sun.

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Solar Panels Work?