Light-emitting diodes (LEDs) are light sources that consist of semiconductor chips. When voltage is applied, the electrons within the diode move, converting energy into light. There are no moving parts in the LED chips and fittings themselves, making them more robust and long-lasting than any other type of lighting.
There are various reasons relating to both energy efficiency and environmental factors as to why LEDs are considered the best choice when it comes to lighting:
- LEDs are excellent at converting energy into light. While incandescent and fluorescent fittings emit a lot of heat, most of the energy in an LED becomes cool targeted light, since their light and heat components are separate. The minimal heat produced is dissipated through heat sinks built into the fittings.
- Due to the technology in LEDs their lifetime hours are considerably longer than others. They last 3-7 times longer than fluorescent lamps and up to 50 times longer than incandescents. That means much lower lamp replacement and maintenance costs. Just imagine the potential savings!
- The next reason will speak to the tree-hugger in us - LEDs contain no environmentally harmful substances such as lead or mercury. And because of the longer life cycle of the LED lights, fewer materials are used throughout the lighting process.
- LEDs also have a considerably better colour-rendering index than most standard lights. They are the ideal choice when perception of detail is of high importance - for example, in production, offices, hairdressers and many other scenarios. LEDs have become widely applied in street lighting as well which makes it much easier to spot your car by the colour (the widely used sodium lamps give a very yellow or even orange light distorting the perception of the colour)!
LEDs are more efficient compared to traditional lights such as incandescents, halogens and fluorescents. The energy efficiency of an incandescent lamp is about 10lm/W with halogen lamps at around 20 lm/W. Fluorescent light efficiency is between 70-90 lm/W and LEDs come in at between 70-199 lm/W, depending on the quality and type of fixture. Some of the latest LED luminaires have efficacies of up to 140 lm/W!
Using LEDs create generous savings as you can replace a 50W halogen with a 5W LED. They pay for themselves normally between 1-4 years depending on the applications and fitting type.
It is not always the number of LED chips in a light that determines its brightness. LEDs provide a more unidirectional light that makes it appear brighter than other types of lighting. Also, the colour temperature and diffusers used will impact on its brightness. Most accurately, the brightness of an LED fitting is measured in lumens or lux. Lumens refers to the total amount of light output from a light whereas lux measures how bright the light is on the surface.
Additionally, LEDs do not require extra time to reach maximum brightness. Other types of lights are based on discharge technology and therefore require some time to reach full output.
How often the fitting will need to be replaced is based on a combination of factors, including the rated lifetime of the fitting and the number of hours is it used each day. If the fitting is rated at 50,000 hours then the replacement period works out as follows.
Hours of operation
24 hours per day
18 hours per day
12 hours per day
8 hours per day
The rated life of an LED light is defined as number of hours it can operate before its lumen output drops below a certain percentage. Research suggests people notice a change in light levels if it drops below 70% of the original output. The lights with be rated to an L70 metric.
One of the key benefits of LED lights is their light beam emits no heat and they do not have infrared or UV components. There is heat generated in the process on energy-light conversion but this is dissipated through the heat sink. It means LEDs have wide areas of applications, since they can also be used in heat sensitive areas such as in food production areas with limited space. Additionally, LEDs don’t attract those pesky bugs.
LED lighting has a wide range of applications. It can be used indoors and outdoors, as it can be supplied in various IP ratings. It is very effective in shops, offices, hotels, stages and anywhere else it requires a well lit environment.
In financial terms, LED lighting is particularly recommended in areas where the lighting is used for long hours in a day (>8hrs/day) - for example, warehouses. These are the conditions where the LEDs will produce the greatest savings in the shortest period of time.