Photovoltaic Solar Basics

With the rising popularity of photovoltaic solar technology, one might be prone to wonder how it works, exactly. While the design of the equipment is quite complicated, the explanation is actually quite simple: it turns heat radiation from the sun into electrical energy. This is accomplished by the semiconductor cells in the panel. The conversion is immediate, so no generation is required. That is why it is actually more correct to say that photovoltaic solar panels “convert” solar energy into electrical, as opposed to saying that they simply “generate” electrical energy. Thermal systems use solar energy to heat water and then use the water to “generate” electrical energy, so it is the thermal collectors that actually generate electricity, not the photovoltaic panels.

The panels are then connected to a series-connected bank of batteries. Think of it as an energy hotel, for the power to be stored until it is needed to be used. It’s not there to stay, it’s just passing through. After all, isn’t that essentially what a battery is? A place to store energy until it is needed? So it should make no surprise here that that is exactly the purpose it serves. This battery bank is necessary because the sun doesn’t shine all day. If you run your house solely based on the sun, you will have no power at nighttime. Therefore, at night, you can use the charge stored up in your battery “hotel”.

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Finally, one must consider how to get the power from the panels and batteries to the rest of the house. The most important thing to note here is that the energy supplied from the panels and batteries is DC (direct current) voltage. That is, it does not fluctuate between positive and negative alternations. Since conventional methods have only generated AC (alternating current) voltage, a voltage that fluctuates so many cycles per second (known as Hertz), most appliances are designed and built to run on AC voltage. While there are many items that may even be more easily produced for DC voltage, there are still far too many homes that run off of the typical power grid. Therefore, an inverter is necessary if you are attempting to power most typical household appliances. Normally, you should be able to split the output from the battery bank and photovoltaic panels to two main lines: one for DC loads and the other for AC loads. Then, all you need to do is wire accordingly.

These are only some of the basic functions of a photovoltaic solar panel. If you want to find out more about how photovoltaic panels work or how the semiconductors convert solar energy into electrical energy, click here.