How Compact Fluorescent Lamps (CFLs) Work

Compact fluorescent lamps, also known as compact fluorescent light or just energy-saving lights are designed to replace Thomas Edison’s old and inefficient incandescent light bulbs. What is a compact fluorescent lamp and how does it work?


What is a Compact Fluorescent Lamp?

A compact fluorescent light bulb consists of two main parts:


Electronic or Magnetic Ballast Base

The base of the fluorescent light bulb is an electronic or magnetic ballast. Whether or not magnetic or electronic ballast is best choice for your light setting depends on several factors:

Compact fluorescent lamps bulbs with magnetic ballasts are known for flickering when they are switched on. In addition to this, they are also heavier than those made of electronic ballasts. In some settings, they are in fact too heavy.

On the other hand we have compact fluorescent light bulbs with electronic ballasts. These are more common on today’s market. They are slightly more expensive, but also have higher efficiency rates than their magnetic counterparts and do not flicker when you light them.

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The Bulb

The bulb or burner is essentially a tube filled with gas. It is most of the times bent to represent the same size as a typical incandescent light bulb. The inside of the tube is coated with white phosphor.

Both electronic and magnetic ballasts usually last about five times as long as the compact fluorescent light bulb or tube.


How Compact Fluorescent Lamps Work

CFLs can be installed in regular incandescent fixtures, and they consume less than one-third as much electricity as incandescent lamps do.

When you flip the light switch, electricity flows from the electronic or magnetic ballast and through the gas-filled tube. The white phosphor gets excited by the electricity and starts emitting light.

This is very different from how conventional incandescent light bulbs work. These contain a filament, which is heated by electricity. The color of the light is white-hot – pleasing to the eye, but a lot of energy is wasted as heat.

Depending on the phosphor formulation, the quality of light differs. Compact fluorescent light bulbs rated as soft white are close to the quality of incandescent light bulbs.


Types and Shapes of Compact Fluorescent Light Bulbs

Tubes and ballasts can either come as permanently attached or in two pieces. If the tube and ballast is separated, replacing an old tube does not at the same time require the replacement of the ballast as well (which has five times the lifespan of a tube).

It is the total surface area of the bulb (burner or tube) that determines how much light the fluorescent lamp emits. A fluorescent light bulb or lamp can come in many different shapes and forms, each one with their own set of benefits and advantages:


Twin- and Triple-Tube Integrals

These are the most common types. Twin-tube integrals consist of a long tube that is bended on top, can be either straight or spiral, and attached to the base at two points. A Triple-tube integral is essentially the same thing, except instead of one tube attached at two points of the base, there are three tubes attached to two points each.

Twin- and triple-tube integrals can also be covered with a casing to help reducing glare.


Modular Quad-Tube

These are built on square ballasts and do not fit in regular incandescent fixtures. They are called quad-tube because the there are two circular tubes attached to two places each.


Circline Ballast Light Bulb

These compact fluorescent light bulbs consist of one circular tube attached to its electronic or magnetic ballast. They are often seen in ceilings.

Are compact fluorescent light bulbs better than incandescent light bulbs? What about LED and halogen lamps? Read the following article to find out: Best Energy Saving Light Bulbs – CFL, LED or Halogen?
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  1. Maryann says

    Ok… But there is no mention of what is exactly the gas used in CFL bulbs. The EPA WEBSITE STATES THAT CFL bulbs contain mercury… and that if one breaks in the home, to open the windows to allow “the mercury VAPOR” out. The only substance that can be considered a gas then would be this vapor. So why the mystery of not disclosing what the “gas” is exactly????

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