Why is PFC done 'equipment-side'?
Look at the two scenarios: -







simulate this circuit &ndash; Schematic created using CircuitLab

In the top scenario a reactive load is power factor corrected back at the source of power and the current flowing down the wires (dotted box) will be, for UK AC and a 0.1 henry load this: -

Current = \$\dfrac{230V}{2\pi\cdot 50Hz\cdot 0.1H}\$ = 7.32 amps

In the lower scenario the power factor correction is done right up at the load and, because the capacitor and inductor are pure components (and perfectly in antiphase) the current flowing down the wires is ZERO.

This means cable power dissipation is zero in scenario 2.