So 30w at 24hrs over two days is 1440wh. If you get lots of sun, you could round down to a 12v 100ah battery, but when it comes to the life and death of little critters, you probably want to round up to 2kwh. Divide by 5hrs of sun per day and you'd need 400w of solar panels. If you're looking for quick and easy, you could probably get something like
this and
this and be done, albeit a little shy on the panels. Buuuuuut, that's no fun, is it?
Nice thing is that you don't need an inverter and can run right off of 12v from the battery, so you could get four of
these and be way over on battery for $500, then maybe a nice 4s BMS from Overkill like
this one, then pretty much any single 400w panel you can find locally, which puts you at 33.3 amps for a solar charge controller, so you could go with a 40a controller or preferably a 60a controller. People seem to like the Epever charge controllers and
these are priced very reasonably on Amazon, plus I think they have a temp sensor option for the battery, which is mandatory if the battery could ever see freezing temps. Add a fuse at the battery positive and with appropriately sized cables, you could possibly put the whole thing together for ~$1400 and it would make for a fun project. I'm guessing you're in SA, which I'm sure will add some cost if you're having to ship overseas.
