Different Types of Light Bulbs and Their Uses
Incandescent bulbs produce a warm light that is very steady and stable. They are the most common bulb you will find in homes. Most standard incandescent bulbs last anywhere form 700-1000 hours, and many are colored soft white to diffuse light. Incandescent bulbs have a filament, usually tungsten, that heats up as electricity passes through. While the main result of an incandescent bulb is heat, it makes quite a lot of light as a by-product. Incandescent bulbs are the most inefficient bulb because most of the energy used to produce light is actually used to produce heat. Because this heat makes the filament fragile, many bulbs burn out at the end of their life when a sudden surge of power (such as the flick of a switch to turn them on) breaks the filament.
Use an incandescent bulb when a low initial cost is needed and when a soft white tone is required.
Halogen bulbs are based on the same principle as incandescent bulbs. While incandescent bulbs are filled with an argon/nitrogen mixture, halogen bulbs are filled with krypton gas. The tungsten filament in a halogen bulb lasts longer because the filament stays stronger. Halogen bulbs are much brighter than incandescent, and are much more energy efficient for the amount of light produced. Halogen bulbs can get very hot, and must be placed in areas without flammable materials nearby. They have a life of a little bit longer than an incandescent and must not be touched because the oils from fingers weakens the glass and can cause the bulb to explode.
Use a halogen bulb when more light than an incandescent can produce is needed. Halogens produce a light that is more similar to daylight and can be used to generate light for crafts and hobbies.
The main benefit of a fluorescent bulb is its long life. The average tube bulb can last between 10000 and 20000 hours. Fluorescent bulbs are filled with argon gas and when electricity is passed through, a small amount of mercury in the tube produces ultraviolet radiation which in turn causes the phosphorus coating of the tube to give off light. Fluorescent bulbs are very efficient and produce little heat. Using new technology, the fluorescent bulb is able to emit light that is very good with color-rendering. They are useful for lighting up large areas and are most commonly found in the office building. Fluorescent bulbs need a ballast to regulate the voltage in order for them to work.
Fluorescent lights should be used when a large amount of light is needed and where heating up the room is undesirable. They are very good for use in garages, basements and workshops. True day light OTT lights can be used for jewelry making and suggestions for using them are found in my guide on planning your jewelry workstation.
Compact Fluorescent Lamps
CFL bulbs are rapidly replacing the standard incandescent for home use. Based on the same principles as the fluorescent tube, CFL bulbs screw right in to standard light fixtures. The ballast is included in the base of the bulb and does not require any other equipment to use. Most CFL bulbs cannot be use with dimmers and can last up to 10000 hours.
A 20-25 watt CFL is approximately equivalent to a 100 watt incandescent bulb.
Use CFL bulbs to replace all your incandescent bulbs as they will save you a bit of money on your electric bill.
High-Intensity Discharge Lamps
High-pressure sodium lamps dominate this category. They work when electric arcs between two tungsten filaments inside an inner glass tube. The inner tube is filled with various metals and when the metals heat to the point of evaporation, the bulb produces light. Sodium bulbs are very high efficiency but produce a somewhat yellow light. HPS lamps produce large amounts of light and can be used to light up very large areas.
Most HID lamps are used to light sports fields, parking lots and roadways, but many residential applications are finding them useful.
Low-Pressure Sodium Lamps
LPS lamps are used when the highest efficiency light is needed. They emit a very yellow light and require a ballast like a fluorescent bulb. LPS lamps produce light through a very similar process as a fluorescent. There is a warm up time before full brightness is achieved and are used when color recognition is not important.
Most LPS lamps are used for driveways, parking lots and pathways because they are much better suited for outdoor uses where the color of the light produced is not important.
LED (Light Emitting Diodes)
LED bulbs are the light of the future. They do not have a filament and can give off nearly white light. While they don't produce enough light to compete with CFL bulbs, they consume the least amount of electricity and produce the least amount of heat. LED bulbs have a very long life span and since LED technology is advancing rapidly, they should be the light of choice for residential applications in the near future.
LED bulbs can come in a wide variety of colors and can be used when colored accent lighting is needed. Because of the large initial cost, but low operating cost and long life, LED lights are being used more and more to replace incandescent bulbs every day.