An ordinary incandescent (ICL) bulb is an extremely energy inefficient for lighting when compared to LED. A ICL bulb requires 60 watts of power to emit 350-400 lumen of light (unit of light) while CFL lights emit 450-550 lumen of light on 14-16 watts. However, they have issues because of their hazardous mercury coat.
LED bulb can emit 600-700 lumen by consuming just 6 watts of power and it saves 90% more energy than regular bulbs. Further, the proportion of lumens that falls in an area from an LED light source is greater than that of a conventional light sources.
How ICL, CFL and LED differ in terms of life?
The LED bulbs have the life of 15000 to 20000 hours which is more than both the ICL bulbs and CFL bulbs.
How ICL, CFL and LED differ in terms of safety and mercury emissions?
ICL has safety hazards because it has both mercury and lead. Further, the halogen lights have halogens (Bromine, Iodine) which are also harmful. CFL has safety hazards because of mercury coating. LED has no mercury and this is what makes them versatile and popular. However, it is not correct to say that LED bulbs are totally safe. Some toxic material are used in them too.