Every technology has a foundation – that piece of innovation that makes it all possible. For solar power, it has to be the semiconductor. These wonderful, silicon-based doodads are spread across roofs around the world. But what in the world is a semiconductor? That is something the average solar enthusiast can’t exactly answer. Let’s not be too hard on ourselves, most of us couldn’t design a light bulb either. But, because rabid curiosity hasn’t killed me so far, I ventured to find out exactly what a semiconductor was. Here is what I found out…as best as I can articulate it.
Two things right off:
- One, semiconductors are not exclusive to solar. They are also used in electronics, a big reason for the recent silicon shortage.
- Two, they are not exclusively made from silicon, although it is still the most common. Other materials, such as cadmium telluride and copper indium diselenide, are also used but to lesser efficiencies so far.
Essentially, semiconductors are the devices in a solar cell that absorb sunlight and enable the separation of electrons from the heat waves. Only when electrons are freed can they be used to generate electrical currents. Hence you have the importance of semiconductors in solar cell manufacturing.
A semiconductor has two traits that are important to the production of electricity: (more…)
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