Two things usually justify or rule out installation of PFC.
1. If your paying penalty,to the utility co., for poor power facotor.
2. If the resultant redcution in kVA demand really translates in to significant saving in utility bills.
In some cases, utility may not be problem but your back up source such as generator kvA rating may be.
Other theoratical benefits such as savings by reduction in I^2R losses etc., which only helps in upsream circuits, alone may not justify PFC installation.
Also look at what percentage of total energy cost the savings will be.
Also if you are unlucky, adding caps may introduce other problems such as harmonics, overvoltages, resonsnace..all of which can be mitigated by proper system analysis.