Compact fluorescent lights are more energy efficient, and are physically different than conventional light bulbs. This is because a fluorescent light go about producing light energy in a different way.
How they work?
A conventional light bulb has piece of resistive wire inside a glass bulb. When an electric current is applied to the wire, it gets hot and begins to glow. As the temperature of the wire increases the brighter the light gets. A typical light bulb will emit 2.5% of its energy as visible light, and wastes 97.5% of its energy mostly as heat.
A compact fluorescent light or CFL uses a long sealed glass tube. To reduce the space this long tube takes up manufactures ether bend the tube in a zigzag, or circular cork screw. The inside of this tube is coated with a fluorite coating. The tube is filled with small amount of mercury vapor. At each end of the tube is small heating element that is used to warm the mercury into a vapor. Since mercury is metal it is electrically conductive. When electric current flows through this vapor the atoms get excited and give off ultraviolet light. When the ultraviolet light is absorbed by the fluorite coating, this causes it to fluorescence. This fluorite coating now is giving off visible light. The light output is regulated by electronic ballast built into be base of the bulb. A compact fluorescent light is about 300 to 400% more efficient then a conventional light bulb.
Pros and Cons to Lighting
Conventional light bulbs pros
1) Are cheap to replace
2) Are easy to purchase
3) Tolerate hot locations
4) Will tolerate some moister
5) Light comes on instantly
Conventional light bulbs cons
1) Waste up to 97.5% energy mostly as heat
2) Don't last long
3) They get very hot
4) Are a potential fire risk
Compact Fluorescent Lights pros
1) Typical 75% saving in energy
2) Last 5 to 8 times longer
3) Gives off significantly less heat
4) Have a reduced fire risk.
5) Ideal for hard to access locations
Compact Fluorescent Lights cons
1) Do not instantly produce light.
2) Do not like hot environments
3) Do not like wet locations
4) Initially cost more
5) Most can not be used with light dimmers
6) May not fit into some light fixtures
Hidden Savings. Since Compact Fluorescent Lights give off less heat than a conventional light bulb. The savings is in reduced air conditioning cost.
How to find a happy home for your CFL?
Since Compact Fluorescent Lights have solid state electronics in them, they do not like water, or hot environments. They do not like light dimmers. Unless the manufacture specifically states it's compatible with light dimmers. Most CFL's come with a standard size screw in type electrical socket, like most standard light bulbs. Locations to avoid would be like range vent hood, inside a refrigerator, or inside an enclosed light fixture that shares the same space with regular light bulb. A recessed can light fixture in an insulated ceiling is a questionable location, outdoors where rain can come in contact with the CFL. Some manufactures make outdoor CFL bulbs. As to respects to the possibility of heat damage. Just remember that CFL's do give off some heat. The larger the rated wattage of the CFL is the more light and heat it will also give off. So if a CFL is in an open light fixture heat should not be a problem. But when the CFL is inside a glass enclosure were the hot air can't escape from fixture easily. This will result in a higher CFL operating temperature. If it gets too hot it will destroy the CFL electronic ballast. To avoid this use a low wattage CFL. Reduce the number of CFL's inside the light fixture. Or change to a different style light fixture. Or change the fixture to a fluorescent type. Remember that CFL's come in many shapes and sizes. So pick the rite one for your application.
Some examples of different CFL's
Some prime locations.
The first locations that should receive compact fluorescent lights are lights that are used the most. This will offer the quickest payback for your investment. For example if you have a light you leave on all night. This would be the first location to make change to CFL bulb. Next would be like table lamps that are generally left on during the evening hours for reading or TV viewing. There are some of the other benefits to using CFL's over conventional light bulbs. An example; if you have an open air light fixture that does not deliver enough light, and does not allow you to increase the wattage of bulb used in the fixture. What you can do is replace all the bulbs with CFL's bulbs. Remember a CFL puts out 4 times the light per watt over regular incandescent light bulb. Plus will also reduce heat output. For example the fixture says MAX 40 Watt bulbs can be used.
Let's do the math.
Let's use as an example a light fixture that uses three 40 watt bulbs. So the total wattage is 120 watts. (40watts) x 3 = 120 watts. Now if we change the three bulbs to 15 watt CFL's. The total wattage is now 45watts. (15watts) x 3 = 45 watts. This is a savings of 75 watts of energy. Now remember CFL's put out 4 times the light per watt. So take (45 watts) x 4 = 180 watts of equivalent light output. In this example we increased light output by 50%, at the same time reducing energy usage by 75 watts.
In this example it's a win win situation.
What to look for in a CFL?
1) Look for the energy star logo on the package.
2) Look for the proper wattage for your application.
3) To make sure the bulb will fit in the fixture before making your purchase.
4) To make sure the bulb is the proper type for your application.
Why look for the energy star logo? When a CFL has the energy star logo means it has met certain testing specification. Bulb starts up in less than one second. CFL has also met minimum efficiency, and longevity standards.