I need to power a DC 12/24 electric fence charger. I was thinking about getting more PV, Watts and Ah than I need in order to power other things. I'm looking at the classic 150. I'm starting to understand how the PV works and the batteries. I don't understand how you get DC 24V out of the classic to the fence charger. Do I need some sort of regulator/breaker or does my battery voltage dictate whether it is 12v, 24v, 48v out?
If you want a bigger solar system - then you will want to get less expensive larger solar panels - they are usually 23v and up . Depending on what your battery voltage is you will need 2 or 3 PV panels in series to charge the batteries using MPPT charge controller like the Classic or Kid ( or Midnite now has newer DIY systems ). The MPPT charge controller takes higher pv voltage and changes it lower to charge the battery. If you have for example a 24v battery system but need 12v for something like a fencer , you would use a DC to DC converter to change battery voltage from 24v to 12v . These are pretty inexpensive depending on the current you need to run. Samlex makes some good reliable converters.
I suggest watching some of the solar tutorial videos on AltE youtube page and there is another guy who also makes lots of do it yourself solar videos - https://www.youtube.com/user/errolprowse.
Larry
Being off-grid and having sheep with eFence, i strongly suggest a factory built solar fence charger, instead of trying to go DIY. There are some pretty strong solar chargers, but if you are trying to keep bears out of beehives, you may need a much higher power system.