Compare LED lighting to compact fluorescent bulbs. Compact fluorescent bulbs are not as efficient as LEDs, they take longer to light up and they contain mercury. LEDs contain no toxic elements. And, according to Amber Angelle, writing for "Popular Mechanics," LEDs are one of the most promising light sources out there in terms of efficiency, longevity and reliability

LED is 90% energy saving compared with CFL,
LED is 60% energy saving compared with Incandescent Bulb