Compact fluorescent lamp (CFL)

• Low energy efficiency of incandescent lamps has made them to be replaced with some others energy efficient alternative.
• Compact fluorescent lamp is one such alternative which can replace almost any incandescent lamp.

CFL consist of two parts:

1. A gas filled tube.
2. Magnetic or electronic ballast which acts as power supply.

• When electricity from the ballast flows through the gas in the tube, it glows with an ultraviolet light.
  Successively phosphor coating on the inner wall of the tube is excited.
• This energized coating emits white visible light throughout the surface of the tube.

The main advantages offered by CFL to choose over incandescent lamps are :

• Compact fluorescent light lasts 8 to 15 times longer than the incandescent lamp.
  It consumes near about 20 to 70% less electric power for the same amount of visible light to that produced by incandescent light.
• Through the CFL is expensive than incandescent lamp, it can save the electricity bills more than five times to its initial buying price.
• It has good luminous efficiency.
• Less cooling loads comparably.
• While replacing incandescent lamps with compact fluorescent light its necessary to compare the light output or lumens and not the watts.
• If someone wants to replace in incandescent bulb of 100 watts which give 1, 600 lumen. CFL of 25W is suitable as it has light output in the same range.

Power equivalent Incandscent and CFL

Incandescent Lamp (Watts)	Minimum lumens	Compact fluorescent lamps (Watts)
40	450	9-11
60	800	13-15
75	1100	18-20
100	1600	24-28
150	2400	30-52
200	3100	49-75
300	400	75-100

• Table shows the extent of less rating of CFL required while replacing incandescent lamp. In addition to this direct saving CFL also saves energy by reducing coating load.
• In the spaces where air conditioning is used and incandescent lamps are lighting, CFL significantly lessens the cooling required as they produce much lesser heat than incandescent lamps.