Many believe Thomas Edison Invented the first light bulb, this is debatable Sir Joseph Wilson Swan from Sunderland invented the first low Voltage High current Light Bulb in 1850 whilst Thomas Alva Edison didn’t invent his Incandescent light bulb until 1879, however both these were predated by Sir Humphry Davy of Penzance, England. He created the first incandescent light by passing current through a platinum strip. It caused a glow and did not last long, but marked the beginning of incandescent light development, He also is the discoverer of the first electric lamp type: the carbon arc lamp.
The Incandescent light bulb of Edison’s hasn’t really changed that much up until recently as the design was simple and the light produced was bright, however massively inefficient as it uses electricity to burn a filament to produce light.
Lighting has a major impact on the electrical drain on the world as nearly 19% of all electricity in the world goes on lighting and almost 66% of all lighting currently used in the world is based on older and less energy efficient technology which were developed before 1970.
Pendant Bulb Types
This Diagram shows the development of lighting technology for pendant type fittings. These are the easiest and cheapest lighting to change as they are a direct swap and not fixture is needed to be changed.
Traditional Incandescent is now banned in many countries due to its 10% efficiency whilst LED is finally at a point where it is a cheap highly efficient bulb, you can now purchase these bulbs from as little as a £1.
LED is now Dimmable contrary to popular belief however these cost a little more due to the process involved.
Fluorescent Lighting (Tubes)
Benefits of Fluorescent Lamps
- Good efficacy (60 – 100 lm/W)
- A broad range of colour rendering characteristics
- Long lamp life (8000 – 16 000 h)
- A broad range of colour temperatures is available.
Limitations of Fluorescent Lights
- Requires control gear
- Light output reduces under cold or hot conditions
Leaving fluorescent lights on saves money rather than turning them off… FALSE it takes 2-8 seconds of energy to turn on a tubed light.
Why Use Fluorescent Lighting
The tubular fluorescent lamp is the most common type of discharge
lamp, accounting for around 80% of the world’s electric lighting.
The discharge within the lamp emits ultraviolet radiation which is
converted to visible light by a phosphor coating on the inside of the
tube. Over the years, the types of phosphor coating used have been
improved, and enhanced alternatives are available to the original
halophosphate coating which is still used today. However, halophosphate
versions no longer meet the minimum colour rendering requirements for
normal workplace interior lighting and so only triphosphor lamps should
be used. These modern alternatives provide better lamp efficacy and
improved colour rendering.
Modern control gear operates at a high frequency and eliminates the
discomfort of lamp flicker associated with older, less complex control
gear. A further benefit of contemporary control gear is the ability to dim
Tubular fluorescent lamps are available in a range of lengths and three
38 mm diameter (T12 lamp) 1938 – 1980
This was the first lamp size to be manufactured and remains popular
today. T12s are typically filled with argon gas, which is not as efficient as
the combination of argon and krypton used in the more modern T8
25 mm diameter (T8 lamp) 1980 – TODAY
The T8 lamp was introduced in the 1970s and provides a more efficient
alternative to the T12 (see above). A range of phosphor coatings are
available enabling good efficacy and colour rendering.
15 mm diameter (T5 lamp) 2000 – TODAY
The most recent T5 lamps are more efficient than the T8 lamp, and are flicker-free as they only operate from high frequency electronic control gear. The T5 lamps are shorter than T8 and T12 lamps, and are designed to fit within 300 mm modules.
Common Tube Ratings
|Tube diameter in 1⁄8 in (3.175 mm)||Nominal length||Nominal power (W)|
|T5||6 in, 150 mm||4|
|T5||9 in, 225 mm||6|
|T5||12 in, 300 mm||8|
|T5||21 in, 525 mm||13|
|T8||18 in, 450 mm||14|
|T8||2 ft, 600 mm||18|
|T8||3 ft, 900 mm||30|
|T8||4 ft, 1200 mm||32|
|T8||5 ft, 1500 mm||58|
|T12||18 in, 450 mm||15|
|T12||2 ft, 600 mm||20|
|T12||4 ft, 1200 mm||40|
|T12||5 ft, 1500 mm||65/80|
|T12||6 ft, 1800 mm||75/85/100|
|T12||8 ft, 2400 m||125|
Compact Fluorescent lamps (Energy saving Bulbs)
The compact fluorescent lamp has undergone considerable improvement in recent years and its increasing popularity looks set to make it one of the most widely used lamps on the market.
In many lighting applications, compact fluorescent lamps provide an energy efficient alternative to standard incandescent lamps which, in the past, would have been the primary option. Compact fluorescent lamps have an average life of between 8000 – 10 000 h. Standard incandescent lamps generally have a life of about 1000 h.
Benefits of CFL’s
- Long lamp life – typically 8000 – 10 000 h.
- Consequently, minimal maintenance is required
- Good energy efficiency, providing up to 80%
- energy saving in comparison to standard
- incandescent lamps
- Life-cycle costing is very favourable in
- comparison to standard incandescent lamps
- Can be used as a direct replacement for a
- standard incandescent lamp
- Available with standard screw/bayonet fittings
- with the control gear an integral part of the lamp.
- Good colour rendering characteristics
- Broad range of applications.
Limitations of CFL’s
- Initial cost is high in comparison to standard incandescent lamp but as incandescent have been phased out CFL’s have dropped in price to fill the void
- Less efficient than standard tubular fluorescent lamps
- Light output diminishes with age, this is always a draw back with the bulb as they normally become poor before the end of life.
- Compact fluorescent lamps require electronic control gear which, with the exception of some small lamps, is a separate item.
- Now being superseded by LED equivalents, especially now LED bulbs have dropped down to the pound range.
- Been known to be aesthetically unpleasing, it cant be argued that CFL’s have a unpleasing unnatrual appearence.
- Contain more mercury than older incandescent about 5mg in total in each bulb
Light Emitting Diodes (LED)
As your incandescents burn out, it’s a good time to consider switching to LED bulbs. By now, you probably know that LEDs have an impressive lifespan (20-something years!) and are very cost-effective. You probably also know that while they’ve come down in price quite a bit, some options are up to five times more expensive than traditional bulbs.
Despite the cost, now’s the right time to switch to LEDs. These bulbs have made significant advances over the last few years, finally delivering the warm light incandescents have comforted us with for decades.
More than ever, there is also an overwhelming number of LED varieties, and choosing an LED is entirely different from picking up an incandescent. Before you head to the store, find out what you need to know about choosing the right LED bulbs.
Learn the lingo
Forget what you know about incandescents — your watts are no good here.
When shopping for bulbs, you’re probably accustomed to looking for watts, an indication of how bright the bulb will be. The brightness of LEDs, however, is determined a little differently.
Contrary to common belief, wattage isn’t an indication of brightness, but a measurement of how much energy the bulb draws. For incandescents, there is an accepted correlation between the watts drawn and the brightness, but for LEDs, watts aren’t a great predictor of how bright the bulb will be.
For example, an LED bulb with comparable brightness to a 60W incandescent is only 8 to 12 watts.
But don’t bother doing the math — there isn’t a uniform way to covert incandescent watts to LED watts. Instead, a different form of measurement should be used: lumens.
The lumen (lm) is the real measurement of brightness provided by a light bulb, and is the number you should look for when shopping for LEDs. For reference, here’s a chart that shows the watt-lumen conversion for incandescents and LEDs.
LEDs aren’t bright enough and have poor light quality.
FALSE This was true at one time, but no more It can be refuted with some technical specs. LEDs have colour temperatures ranging from 2,500K (warm white) to 6,500K (daylight), and Colour Rendering Indexes between 75 and 85, with some high-end LEDs topping 90.