Yeah. You don't really want to go down that road unless you are forced to. There isn't any real money savings and you don't know what you are in for. I did alot of research to try and talk my customer out of it.
1.) You only save in I2R losses. Unless you are being penitalized
2.) It can improve PF, but it can also increase Harmonics
3.) If harmonics are present care has to be given to protect the Caps
4.) Switching Caps can cause causes Capacitive Ringing around 200% V
5.) Contactors for switching capacitors often prematurely fail because they don't like an instantaneous change in voltage.
6.) Transients from Utility Capacitor Switching can be amplified by customer capacitors causes voltages excesses of 200%
7.) Under no-load conditions if capacitors are not switched off they can cause an over voltage.
8.) When they fail you hope you are not near them.