| Due to the relatively high cost per watt, LED lighting is most useful at very low powers, typically for lamp assemblies of under 10w. LEDs are currently most useful and cost-effective in low power applications, such as nightlights and flashlights. Colored LEDs can also be used for accent lighting, such as for glass objects, and even in fake ice cubes for drinks at parties. They are also being increasingly used as holiday lighting. LED efficacies vary over a very wide range. Some have lower efficacy than filament lamps, and some significantly higher. LED performance in this respect is prone to being misinterpreted, as the inherent directionality of LEDs gives them a much higher light intensity in one direction per given total light output. LED technology is useful for lighting designers because of its low power consumption, low heat generation, instantaneous on/off control, and in the case of single colour LEDs, continuity of color throughout the life of the diode and relatively low cost of manufacture. |