Incandescent lamps

From CopperWiki
Jump to: navigation, search

Incandescent lamps are sources of artificial light that work on the principle of heat-driven light emissions. These Incandescent lamps, one of the most important inventions of modern times are now taken or granted like other everyday conveniences that most affects our lives. It was invented in 1879 by Thomas Alva Edison.

In February, Australia announced a nationwide ban on incandescent bulbs, which will go into effect in 2010. The country's environment minister said the move will cut greenhouse gas emissions by 800,000 tons by 2012


Why should I be aware of this?

  • Though we call them "lights," traditional incandescent bulbs are actually small heaters that produce a little light — and waste a lot of energy making heat.

All about incandescent lamps

The glass enclosures are made from a ribbon of hot glass that's first thickened and then blown into molds to form the bulb shapes. These enclosures are then cooled, cut from the ribbon, and their insides are coated with the diffusing material that gives the finished bulb its soft white appearance.

The filament is formed by drawing tungsten metal into a very fine wire. This wire, typically only 42 microns (0.0017 inches) in diameter is first wound into a coil and then this coil is itself wound into a coil. The mandrels used in these two coiling processes are trapped in the coils and must be dissolved away with acids after the filament has been annealed.

The finished filament is clamped or welded to the power leads, which have already been embedded in a glass supporting structure. This glass support is inserted into a bulb and the two glass parts are fused together. A tube in the glass support allows the manufacturer to pump the air out of the bulb and then reintroduce various inert gases. When virtually all of the oxygen has been eliminated from the bulb, the tube is cut off and the opening is sealed. Once the base of the bulb has been attached, the bulb is ready for use.

Incandescent lamps and environment

The incandescent bulb is an energy guzzler. Just 5 percent of the electricity it uses goes to light the bulb; the other 95 percent is heat. Improving light output and lowering heat output would reduce demand for electricity from coal-fired power plants, which emit carbon dioxide. Carbon dioxide, most climate scientists say, is the single largest contributor to global warming.

The 100w version is the most popular type sold. It is used in ceiling lights. The 60w bulb is usually used for table lamps and reading lights. Disposal of incandescent lamps is however easier than that of CFL as it contains no toxic substances.

What can I do?


  • If every household replaced just three 60-watt incandescent bulbs with CF bulbs, the pollution savings would be like taking 3.5 million cars off the road!
  • Incandescent bulbs are known by how much power it takes to light them—a 40-watt bulb is on the dim side and uses less power; a 100-watt bulb is bright and uses a lot of energy.


  • Incandescent Light Bulbs
  • How to pick a better bulb
  • Lights go out as Britain bids farewell to the traditional bulb despite health fears about eco-bulbs:Mail UK
  • Light bulb History