There are 4 main types of residential lighting. Each produces light using a different technique and each is manufactured a different way.
Almost the oldest form of lighting, incandescent is one of the most inefficient forms of lighting and is now banned in Australia. The warm light source is delivered by heating a metal filament to an extremely high temperature, thus producing a usable byproduct - light.
Typically the life span of an incandescent light is quite short (<1000 hours) and they can be dangerous to use due to explosions at end-of-life, glass breakage and fire risk.
Providing a high colour rendering ability but with minimal luminous efficacy, they are now replaced by LED, CFL and halogen light sources.
Fluorescent lamps and more commonly Compact Fluorescent Lamps (CFL), are a relatively efficient way of creating light. Heating mercury-based gas enclosed in the glass spiral tube produces an ultraviolet (UV) light, which is then passed through a white coating or filter that changes the UV to visible light. CFLs were the answer for efficient lighting before LED technology became available and due to this, CFL technology was steadily adopted to replace incandescent lighting.
The lifespan of fluorescent lighting is typically higher (up to 10,000 hours) than incandescent lighting (up to 1,000 hours), but unfortunately CFLs have their own inherent problems.
Due to the mercury content in fluorescent lights, disposal at end-of-life now means special recycling facilities are required. In the manufacturing stage, employees can be exposed to the poisonous element, causing even more concern about health and safety issues. Use in the home also has an element of risk - although a small amount (1-5mg) of mercury is present in a CFL, the releasing of mercury vapor in the home is concerning.
Like CFLs, halogens work by heating a tungsten filament surrounded by an inert gas mixed with the element halogen to an extremely high temperature. Similarly, this produces heat and a byproduct - light. Halogen MR16 and GU10 downlights were until recently used in most new homes in Australia.
The MR16 version is generally a 12 volt lamp which requires a transformer to convert 240 volt AC mains power to 12 volts. This consumes power as well as complicates the installation process somewhat. Halogens pose a huge fire risk, especially when installed too close to roof insulation.
LED (Light emitting diode)
Light emitting diodes are a solid state electronic component. Recent development in the LED industry has significantly improved the quality, functionality and abilities of the new LED chips. Due to this we have seen an incredible growth in LED products. Offering the widest range of colours, light outputs, fixtures and new features, LED technology is now perhaps the only viable solution to the world's predisposition towards a sustainable future.
The following table will give you an idea why LED lighting is the way of the future.
|Warranty||N/A||N/A||>2 years||>5 years|
|Lifespan||1,000 hours||2,000 hours||10,000 hours||50,000 hours|
|Colour||Warm||Warm||Warm or Cool||ALL|
|Initial Purchase Price||Low||Low||Medium||High|
|Colour Rendering Index (CRI)||100||95||50||80 - 94|
Other forms of lighting
There are of course other lighting technologies, including neon, argon, plasma, oil, carbon, carbide, metal halide, sodium vapor and xenon. These all suit particular applications, but generally a more efficient LED equivalent is now available.