A solar panel, or photovoltaic panel, is comprised of a myriad of parts. Usually a protective casing of metal (the frame), a glass or Plexiglas cover shields the top, and a covering hides the parts from the rear. Each of these protects the parts inside from the weather for the 20 year warranted lifespan. Lasting more like 30 years, these protective coverings enable solar panels to be resilient enough to withstand "normal" weather and operating conditions. Assuming the protective skins, make sense, and their presence well reasoned, let's move onto the guts of a solar panel.
A solar cell, is the solid state electrical device inside a solar panel which converts light energy from sunlight into DC electrical power. Photons, the light energy carriers in sunlight, collide with the solar panel and are absorbed by these solar cells. Each solar cell is comprised of semi conducting materials, such as silicon, which expend the absorbed electrons down the wire. As with batteries, a single cell is not adequate to power today's electronics, so manufacturers assemble a number of solar cells into a solar panel. Solar panels are easier to handle, install, and in groups provide adequate power to run even the largest buildings and installations. By encasing the delicate solar cells in a solar panel, packaging is normalized, and protective surfaces are applied in climate controlled manufacturing processes. This improves both solar panel effectiveness (efficiency %), extends their lifespan in real terms, and reduces the cost of the panel itself.
The energy generated from solar panels, the watts in electrical power terms, is really what matters. Each solar cell in the solar panels produces a bit of power. By connecting these cells in both parallel (positive to positive) and series (negative to positive) arrays, we can increase both the voltage and amperage to levels worth using on the power grid. When looking at a solar panel, you can see partitions, like borders, throughout the panel. These borders are either the edges of the panel framing, the edges of the individual cells, or the solder making the parallel and series connections between the cells.
Okay, but how does it really make power?
The solar cell converts the light energy to power via the photoelectric effect. Often incorrectly referred to as the photovoltaic effect, the photoelectric effect is the process of materials shedding electrons as a result of absorption of electromagnetic radiation of very short wavelength. Electromagnetic radiation is just a technical term for the visible and ultraviolet light spectrums, and should reinforce the necessity of sun block at the beach. The German physicist, Heinrich Hertz, noticed that certain materials exposed to sunlight and ultraviolet light reacted by giving off a current in 1887. The phenomenon is also known as the "Hertz effect" is the basis for modern solar cells inside the solar panel.
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