Not sure some of you understand the way the more expensive MPPT charge controllers work. With series panels sending a higher voltage to the MPPT controllers, the controller converts the excess voltage to current. Example: With Four 5.5Amp panels wired in series, a proper MPPT charge controller can output (charge) your battery bank at near 22 Amps current. Well engineered MPPT controllers can operate up to 98% efficiency.
Another advantage of using series panels instead of parallel panels is that when the sun gets so low that any individual panel operating in parallel cannot generate enough voltage for the charge controller to work, series wired panels are still outputting enough voltage for the controller to provide charge to the batteries.... thus extending the daily charge time.
