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How many wattage of solar panel I need to diy to charge 12 volts 70 amps battery? Answered

Kindly refer the supplied block diagram below.



Best Answer 5 years ago

It depends on how quickly you want to charge the battery bank, how quickly you want to deplete the bank (discharge on your useful load).

You could use a 1 watt panel and charge a HUGE battery bank over a period of months.
You could use 10kW of solar panels to charge a small battery bank in a few minutes...

So the answer to your question is a question: how much power do you NEED?