How much energy savings with window tinting?

We have large sliding doors in Kihei, HI. We are considering window tinting to save energy. How much did you save on your energy bills by tinting your windows? They are west facing, and get much sun.|||Air conditioning is a large make-up of your energy bill. Tinting your windows will reduce infrared penetration into the house meaning less heat getting into the house from sunlight so you use the AC system less.