A lighting system (100, 200, 300) comprising a controller (102, 202, 3) for generating a control signal (103, 203) and comprising a lighting arrangement (106, 206), the lighting arrangement (106, 206) being configured to emit mixed light being a combination of first light (L 1) and second light (L 2), the lighting arrangement (106, 206) comprising a first light emitter, a second light emitter and a driving circuitry (104, 204, 2), the lighting arrangement (106, 206) being configured to receive a control signal (103, 203) from the controller (102, 202, 3), wherein - the control signal (103, 203) indicating a first required light emission by the first light emitter and a second required light emission by the second light emitter, - the first light emitter being configured to emit the first light (L 1) of a first color distribution and the second light emitter being configured to emit the second light (L 2) of a second color distribution being different from the first color distribution, - the driving circuitry (104, 204, 2) being configured to drive the first light emitter at a first power level (P 1) in response to the received control signal (103, 203) and to drive the second light emitter at a second power level (P 2) in response to the received control signal (103, 203), characterized in that the controller (102, 202, 3) is being configured to - obtain a required illumination level (I min), a first efficiency ratio (R 1) and a second efficiency ratio (R 2), the first efficiency ratio (R 1) being a ratio between an amount of power (P 1) provided to the first light emitter and an amount of the first light (L 1) received at a relative position with respect to the lighting arrangement (106, 206), the second efficiency ratio being a ratio between an amount of power (P 2) provided to the second light emitter and an amount of the second light (L 2) received at the relative position, - determine the first required light emission and the second required light emission to obtain, when the said light emitters (108, 114) emit light in accordance with said required light emissions, an amount of the mixed light received at the relative position being at least the required illumination level (I min) while an amount of power consumed by the lighting arrangement (106, 206) is minimized. - the control signal (103, 203) indicating a first required light emission by the first light emitter and a second required light emission by the second light emitter, - the first light emitter being configured to emit the first light (L 1) of a first color distribution and the second light emitter being configured to emit the second light (L 2) of a second color distribution being different from the first color distribution, - the driving circuitry (104, 204, 2) being configured to drive the first light emitter at a first power level (P 1) in response to the received control signal (103, 203) and to drive the second light emitter at a second power level (P 2) in response to the received control signal (103, 203), - obtain a required illumination level (I min), a first efficiency ratio (R 1) and a second efficiency ratio (R 2), the first efficiency ratio (R 1) being a ratio between an amount of power (P 1) provided to the first light emitter and an amount of the first light (L 1) received at a relative position with respect to the lighting arrangement (106, 206), the second efficiency ratio being a ratio between an amount of power (P 2) provided to the second light emitter and an amount of the second light (L 2) received at the relative position, - determine the first required light emission and the second required light emission to obtain, when the said light emitters (108, 114) emit light in accordance with said required light emissions, an amount of the mixed light received at the relative position being at least the required illumination level (I min) while an amount of power consumed by the lighting arrangement (106, 206) is minimized.