What is a 12v solar panel and why 12v is such a magic number? First of all let’s talk about kind of electricity generated by solar panels, because it’s different from what runs in power outlet in a typical household. Solar panels generate so called direct current electricity, while regular 110V power outlets give you alternating current. Because it’s a different kind, you can not really compare 12V to 110V. So, where solar panel with 12V comes from?
There are two different kinds of electrical solar systems. Completely stand alone and independent setup is called off-grid system, while solar panels hooked up to regular utility grid is called on-grid. For both cases the same kind of solar panels is used and usually it is 12v solar panels, because standard battery is 12V. For example battery in your car outputs 12V direct current electricity too. This is why if you get a solar panel 12v would be the most common voltage.
12v solar panel
It does not mean that you can’t have different voltage (especially if you make your panels yourself). You also can combine several panels to get higher output voltage if needed, so you could get 24 volts out of two 12v solar panels, 36 volts out of three 12v solar panels and so on. Some batteries for off-grid systems are 24 or 48 volts, in this case you will have to combine several panels in order to be able to charge your batteries.
The last thing to consider (this mostly applies to RV solar panels though), what kind of appliances you will be running from your solar electricity. There are plenty of standard 12V dc appliances available, so it will really save you a lot of headache if you equip your solar system with standard 12V batteries and 12v solar panel, in this case you don’t have to convert electricity.