I want to know what capacity of a solar panel will charge a 12v 200AH deep cycle battery to full charge?

Question

I reside in a region with average sunlight. Also if I am running a 2.5W inverter at full capacity, how many batteries would I need to run for 10hours.

Answer 1

Give Irv the best answer, but I want to mention that 33 kWh a day is an awful lot to demand of a battery-powered residential system.  If your plan is to be off-grid, you would want to see if you can get that number down to 10, or even 3, kWh a day.

If you are willing to wait long enough, you can charge a lead-acid battery at 1/20 C - that is, the 200 amp-hour battery (each of them) can be charged at a 10-amp rate.  Assuming that a penel is 18 volts, that means a 180-watt panel for each of these batteries.  If your goal is to charge up in one day's sunlight, you'd need 4-6 times as many panels (per battery), depending on how many hours of peak sun you get in your area.  As you can see, this is an expensive proposition, and why off-grid cabins generally go very modest on electrical requirements.

Answer 2

* I think you mean a 2.5 KW. inverter right?

At 10 hours, figuring in losses you need about 33KWH. per day.

That's 14-15 batteries, (You don't want to run them into deep discharge.

* 'Average sunlight" - you get about 4-6 hours of useful insolation

per day, as a minimum, (Seasonal variations), depending on your latitude.

(What do you plan to do if you get a few days of cloud/rain?)

A 12V. 200A.H. battery stores 2.4 KWH. of energy, will require about

2.8 KWH. to charge.