Voltage at maximum power

Voltage at maximum power is the voltage across a PV module, string or array at the operating point where voltage and current together produce the highest power under stated conditions. Solar datasheets often label it Vmp (voltage at maximum power) or maximum power voltage and list it beside Imp (current at maximum power), Voc (open-circuit voltage), Isc (short-circuit current), Pmax (maximum power) and STC (standard test conditions). The value helps compare module strings with inverter, optimiser or charge-controller voltage windows, but it is not the same as open-circuit voltage, maximum system voltage, household mains voltage, export capacity, annual generation, DNO acceptance, MCS certification, roof suitability or proof that a system will operate at that voltage all the time.