A solar panel is a collection of many small solar cells spread over a large area. These solar cells work together to provide sufficient energy to power a given item. (Northwestern University) Their creation is a very delicate process which is why many of their advancements did not come until last quarter of the 20th century. In this period, advancements in semiconductors and photovoltaic products allowed efficient and cost effective solar panels to be produced. (Solar Panel Info)
There are two types of solar panels: crystalline and amorphous. In both types, the key component is silicon which is cut into tiny disks less than a centimeter thick. Silicon is a “non-metallic chemical component that makes up 30% of the earth’s crust and is the 7th most common element in the Universe.”
Amorphous solar panels are cheaper to manufacture because they’re less likely to break, they use less silicon. Unfortunately, their output is typically lower than amorphous panels, which means their installation takes more space. They also deteriorate faster than crystalline panels so their power output decreases faster during years of use.
They consist of a very thin layer of “silicon atoms and dopants simply sprayed onto backing material – typically glass or metal , but also on plastic surfaces to make flexible solar panels, or on roofing tiles to make solar roof tiles.” These silicon layers can be 100 times thinner than silicon wafers.
Crystalline solar panels use silicon sliced in thin disks called wafers that are a few millimeters thick. They are shaped, polished and any holes are filled in.
To generate electricity, dopants or contaminants are added to the silicon wafer. This is done by putting a layer of phosphorous on the surface and heating it. The phosphorous atoms will then diffuse into the silicon wafers.
The “doped” silicon wafers are put together to form the solar cell. These solar cells are put...