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There are benefits from using higher voltage panels that can be realized when a system is designed for an MPPT controller.
The downside is that MPPT requires some amount of excess panel voltage over charging voltage to do its work (see below). MPPT advantage may be minimal or nonexistant when nominal panel voltage matches nominal battery bank voltage (12v panels and 12v battery, for example).
Worst case scenario:
…means the controller can't do MPPT charging above 12.66v; we have effectively wasted our money on that $$ MPPT controller. So make sure there is sufficient (voltage) headroom for the MPPT to operate:
Input voltage is a balancing act between efficiency / heat reduction (requires lower input voltage), the ability to overcome self-consumption losses under all conditions (requires higher input voltage), wire size and length (higher input voltage), and shading mitigation (higher input voltage).
MPPT manufacturers always specify a maximum voltage coming into the controller; some also specify a minimum or optimium voltage for MPPT operation: