What does pf mean for photovoltaic panels

The power factor represents the ratio of active power (watts) to apparent power (volt-amperes). Solar panels are photovoltaics and make up a PV system. It is a measure between the “real power” (measured in kW) and the “apparent power” (measured in kVA) drawn by. . Power factor is a measure of the phase diference between the voltage and current in an AC power system. It is the energy efficiency expression and is usually expressed in percentages. [PDF]