High-power light-emitting diode (LED) efficiencies strongly depend on device type and operating conditions. Measurements of input power, luminous flux and CIE colour coordinates are performed on commercial phosphor-white and red-green-blue (RGB) LED types selected from three manufacturers. Experimental results allow for a comparative efficacy evaluation of both LED technologies for making white light. Two approaches are used for this comparison, ie at constant 300 K junction temperature and for a fixed
