A controller system configured to control an electrochromic device and method thereof are provided, wherein the controller system includes an electrochromic device having a first substantially transparent substrate, a second substantially transparent substrate approximately parallel to the first substantially transparent substrate such that a chamber is defined by the first and second substantially transparent substrates, and an electrochromic medium between the first and second substantially transparent substrates, and a controller in communication with the electrochromic device, wherein the controller is configured to monitor electrical power supplied to the electrochromic device and adjust the electrical power supplied to the electrochromic device to maintain the electrochromic device in an approximately minimum transmission state.