I'm working off of a pre-existing mini fridge, what solar panels could I possibly use to store in a battery?
Check out Will Prowse on YouTube. He's the owner of this forum, and has some awesome step-by-step videos on how to build a solar charging system for something like a fridge. His "Milk Crate" systems would probably be what you're looking for.
Your first step would be finding out how much power your fridge consumes per day, and how much backup time you would like to have. Once you have those numbers you can find out how big your system needs to be. A kill-a-watt meter would tell you the AC power draw in watts.
I have this one and it works well enough.
Just as an example; let's say your fridge uses 1000 watts per day (probably not close but it's a nice even number). You want to be able to charge your system and run the fridge while the sun is out, so your panels would need to produce a MINIMUM of 1000w a day, really it would be more, because of losses on the system, and AC inversion.
If you get about 4 hours of sun per day, you need to have panels that will produce a thousand watts total over the course of the day. So a 300 watt panel, for 4 hours would make 1200 watts total while the sun is out, enough to fill your battery for a single day of fridge use. Double that if you'd like to have two days of backup, in case it gets cloudy.
If that fridge uses 1000 watts per day, your battery will need to be the same size (of course in reality it needs to be bigger because of losses, oversize by at least 30%, IMHO). For two days it would need to be 2,000 watts from the battery.
There are a ton of variables involved, amount of sun per day, battery type, fridge type, system losses, so it's hard to tell you exactly what you need without having your specific numbers.
If you have any other specific questions I'd be happy to help!
Edited: some bad math.
