Question: how much solar power do i need to charge a 12 volt battery?
Answer: For a 12V system, if you need to replace 100A/h of charge to your batteries each day, and you have 8 sunlight hours in each day you will need... 1200WH / 8H = 150W of solar panels. In reality it is recommended that you always overrate your requirements by at least 20%, therefore you would need 180W of solar panels.