A variable transmittance window system is provided and includes at least one variable transmittance window. At least one energy harvesting device generates electrical power. A power supply circuitry maximizes the electrical power. At least one energy storage device is charged by the electrical power. A slave control circuitry controls a transmittance state of the at least one variable transmittance window, the slave control circuitry being powered by at least one of the power supply circuitry and the at least one energy storage device. A master control circuitry monitors the slave control circuitry, wherein the master control circuitry is operable to issue a wireless override signal to the slave control circuitry such that the slave control circuitry changes the transmittance state of the at least one variable transmittance window to an override transmittance state.