LED lights. What they are and how they work.

The LED is an electronic component that, when a minimum current passes, emits a light without infrared and ultraviolet rays, lighting immediately.

LED (Light-Emitting Diodes) technology represents the evolution of solid-state lighting, in which the generation of light is obtained by semiconductors instead of using a filament or a gas. The LED lighting is more energy efficient, has a longer life and is more sustainable.

It also enables innovative and creative usage solutions that integrate light into our homes, cars, stores, and cities. LEDs are destined, over time, to replace traditional incandescent lamps and fluorescent lamps.

Energy saving

Thanks to the high illumination characteristic of the lamps and LED bulbs, it is possible to replace with them also the fluorescent lamps (compact or neon) with equivalent to LEDs that consume much less energy, that is power (in watts) decidedly lower, achieving significant economic savings.

For example, it is possible to replace a normal 40 W neon lamp (of the T8 type with a diameter of 26 mm and a length of 120 cm) with a "LED tube" (composed of almost 300 small LEDs) that consumes no more than 17 W.

In this case, assuming an electricity cost of € 0.15 / kWh and average use of 6 hours per day, the annual consumption with the two different lamps would be 87.6 kWh and 37.2, respectively kWh. Therefore, the annual savings in using them LED lamp instead of the neon fluorescent lamp would be 50.4 kWh, and therefore € 7.5.

Duration

The LEDs maintain 70% of the initial light output even after 50,000 hours, according to EN50107 standards. This does not mean that it is necessary to replace them after this period, if this reduction does not create excessively discomfort they can be safely used until the complete loss of brightness, estimated at 100,000 hours.

Comparing the duration of the LEDs with respect to traditional lamps and assuming an average operation of 6 hours per day, we note that:

·        The average life of a filament light bulb is around 1000/1500 hours (250 days)

·        The average life of a discharge lamp is around 4,000 hours (666 days)

·        The average life of a fluorescent lamp is 6,000 hours (1,000 days)

·        The average life of a LED lamp is 50,000 hours (8,333 days)

High luminous efficiency

The luminous efficiency of a light source is the ratio between the luminous flux and input power. The size is expressed in lumens/watts. The luminous flux is defined based on the subjective perception of the average human eye and corresponds to a particular curve within the visible light spectrum. A light the bulb emits radiation even outside the visible band, usually in the infrared and ultraviolet, which does not contribute to the sensation of brightness. A lamp has a higher luminous efficiency the more it is able to emit a spectrum suitable for human perception.

Currently the LEDs have a luminous efficiency up to 120 lm / W, compared to:

·        13 lm / W of incandescent lamps

·        16 lm / W for halogen lamps

·        50 lm / W for fluorescent lamps

It does not pollute and does not contain hazardous substances

The LED contains silicon dust, does not contain gases harmful to health and has no toxic substances, unlike fluorescent and discharge lamps (metal halides and sodium vapors).

Total absence of light pollution; the LED shines but does not saturate the environment.

There are zero emissions of UV (ultraviolet) that in general are harmful to humans for long exposures over time. Also, the emissions of IR rays (infrared radiation), which are harmful to the eyes due to direct exposures, are zero.

These emissions are also very harmful to the textile and leather trade, materials that are very sensitive to UV rays. Loss of color brilliance and sclerosis of materials, particularly natural and therefore more valuable ones, are often the inevitable consequence of long exposure to artificial light: one more reason to use LEDs in the lighting of business premises.

LEDs do not emit warm light

The LEDs generate heat, but keep it inside, in fact, the casing is able to control the heat generated and to dispose of it to external heat sinks. The power used is thus best used for lighting, optimizing efficiency. The average temperature is rarely above 50 °. The LEDs can, therefore, be installed in contact with wood, plastic, and all those materials that fear excessive heat.

Considerable savings can be made in air-conditioning a very bright environment: in fact, an incandescent or halogen lamp produces a considerable amount of heat dispersed in the environment and normally, when calculations are carried out for the design of an air conditioning system, it is considered as a heat source to be cut down by about 75 W. The equivalent source of light, but with LEDs, is evaluated with a redundant margin of about 15 W.

No maintenance

The maintenance costs of the LED lighting equipment are estimated at around one hundredth compared to the sodium plants currently in use, therefore practically zero.

Compatibility with all attacks

The types of LEDs on the market are compatible with existing dimensions/connections/ supply voltages: just unscrew and screw, remove and insert in place of the other lamps.