Solar energy reaches the glass as visible light, ultraviolet light and infrared radiation. Infrared is the part you feel as heat, and it is invisible, which is why a light film can still make a real difference to cabin temperature. Kepler's nano-ceramic construction is designed to reject solar energy across the spectrum with particular attention to that infrared band, so less heat enters the cabin in the first place and the climate system has less to remove. Reducing ultraviolet exposure at the same time helps protect seats, trim and dash surfaces from fading over the years. Because figures are quoted per film and shade, ask your Kepler dealer for the data on the exact combination you are considering for your Tesla.
Ask a local tinter whether they carry Kepler film or can get it. For more information, see quick quote.