ANSWER:
To calculate the battery capacity bank size, you need to consider the energy requirements of your system and the duration you want it to operate without recharging. The formula is:
Battery Capacity (Ah) = Total Load Power (W) \times \text{Operational Hours}}{\text{Battery Voltage (V)} \times \text{Depth of Discharge (DOD)}}
Make sure to convert all units to be consistent (e.g., watts to kilowatts, hours to ampere-hours). The depth of discharge is the percentage of the battery’s total capacity that can be used before recharging.
For example, if you have a 12V system with a total load of 300W, you want it to operate for 5 hours, and you allow a 50% depth of discharge:
[ \text{Battery Capacity (Ah)} = \frac{300 \times 5}{12 \times 0.5} ]
This formula gives you the required battery capacity in ampere-hours (Ah).
