Battery capacity Calculator
First you have to decide on the system voltage. A simple rule of thumb is this: If there are 12 Volt loads or it's a small system (a few hundred Watts), make it 12 Volt. Otherwise make it 24 Volt. Only think about 48 Volts if you have telecoms equipment to power or it's a very big system, at least 1 kW (1000 Watts).
To use this calculator, just input the daily energy consumption and select the system voltage and number of days autonomy required. The value returned is the minimum battery capacity expressed in Ampere-hours at the system voltage.
Please note: The results of this calculator are approximate and are based on a maximum depth of discharge of 80%.
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