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  • How to Size Your Off-Grid Solar Batteries

    Hello Ronnie, my name is Robert and I might be able to assist you here with your situation. This is perhaps complicated, but math never lies. The 100 watt mono solar panel with a 20 Amp Charge Controller only deliveries to the battery (12 Volts X 5.7 Amps )= 68.4 watts of output not 100 watts. Think about this for just a minute, you can only draw a maximum of 50 Ah from the battery. Therefore 50 watts for 1 hour = 50 Wh / 12 Volts = 4.166 Amp hours for every hour that light is on. Lastly a 1500 Watt inverter requires about 125 amps of current at full power. You are playing with fire my friend. Be safe and use a 300 to 500 watt inverter with this 100 Ah battery.

    Hey Richard, just curious what type of charge controller you have, MPPT or PWM. Can you give the specs on the panels Vmp and Imp.

    Hi Alvaro, my name is Robert and I hope you are checking back here for answers. Do you want to know how many amp hours you are removing from the 48 volt battery bank. So then 220 VAC / 40 Amps AC = 8800 Watts of electrical appliances. Divide by the 48 Volts and you are drawing approximately 200 Amps DC. Let me know the size of the battery bank, I would be interested in pictures as well.

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