Solar panels needed for a 24 v system

[Linda]

I have generator 12 x 2v batteries and an inverter/charger. How many 200w panels would I need.

[SunEagle]

Hello Linda and welcome to Solar Panel Talk

To determine how many 200 watt panels you need will require us to know what your 24v battery system Ah rating is. A simple calculation would be having charging amps approximately 1/10th the Ah rating. Once you have that info you multiple it by 24v and you will get an approximate solar panel wattage.

[Sunking]

You need at least 72 cells in series. If that 200 watt panel is 54 or 60 cells will require two panels in series, but your question is NOT VALID because there are two requirements that have to be met.

One is the minimum cell count which is 36 cells for every 12 volts of battery. The second is the minimum power required to push the minimum charge current into a give battery capacity at a give voltage which you have not specified. A battery requires at least a C/10 charge current.

Example if the battery is say 200 AH you need at least 20 amps and on a 24 volt battery would be 25 volts x 20 amps = 500 watts.