How big of a solar panel do I need?

[Arcticdude]

I don't know if 45W will be enough to keep all 3 banks up. You've only got 3.75A at maximum ( if its a 12V output), splitting that 3 ways and accounting for inherent losses will leave maybe 1A per bank. Is that enough? I don't know. One of the smarter folks will be along shortly to more thoroughly answer your question.


Maybe a better question is why bother with the solar? With 3 decent smart tenders, you'll draw less than 1A of 120V most of the time. How long will it take to just recoup the cost of the solar panel, much less a decent controller?