Disclosed herein are a power control system (110) and method for a light emitting diode (LED) lighting device. The system includes a rectifier (125) to rectify an input voltage, a squaring module (145) for squaring the rectified input voltage to produce a squared input voltage value; a filter (155) to filter said squared input voltage; a first function generator (160) for applying a first function to determine a light control signal (165); a second function generator (170) for applying a second function to determine a conductance factor (175), wherein said first function and said second function are independent functions of the root mean square (RMS) value of said input voltage; a multiplier (180) for multiplying said first multiplier signal with said rectified input signal to determine a current control signal (185); and a power supply (190) for determining an input light power to said LED lighting device and an input load power to a dissipative load (120), dependent upon said light control signal (165), said current control signal (185) and said rectified input voltage (140).