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Why prefer LED lights to other light sources (fluorescent, HID, HPS, etc.)

 

Nowadays, the main reason for switching to LEDs is energy saving. Depending on which luminaries are initially in use, 3 to 10 times the energy savings will be achieved. Thus, despite a slightly larger initial investment, the average payback period is about two years. In some cases even under a year.

First of all, the LED luminaire is fundamentally different in physical design. If most light sources (fluorescent tube, energy saving lamp, high pressure sodium lamp, etc.) are isotropic (emitting light at 360 ° or in all directions), LEDs will emit light in one direction (see also the picture below). The light from the most common light sources must be transformed into a useful light (reaching the desired surfaces) using reflectors. This means that the luminance is up to 25% -40%. LED reflectors are not required. The desired result is obtained by selecting the diode and the appropriate angle of the optics.

Secondly, as shown in the figure below, in the last decade, there has been a big leap in the luminous efficiency of LED chips. Essentially, this means that, for the time being consumed, LEDs are already clearly lighting the best room. This, in turn, means that, unlike the traditional approach, whereby the luminaire power (W) was spoken to achieve the desired light, the corresponding metric must be adjusted to the luminous efficiency indicator (lm / W).

Third, the high added value of LEDs is a high color index (CRI – Color Rendering Index). The color separation index shows how naturally a person perceives visible colors in an artificial light source in comparison with natural light (sunlight). A light-colored light (index of about 70 and less) seems to be “dark” despite its power. With such light it is extremely difficult to distinguish between colors and adjacent objects. Maximum color separation index is 100, that is, daylight. The higher the CRI, the better the person perceives the colors of the colors. According to generally accepted perceptions, an acceptable color separation index starts at 80. A normal HPS (high pressure sodium lamp) has eg. color separation index ~ 24. Therefore, despite the provision of a sufficient amount of light (lux), it’s not worthwhile to use indoors because the HPS light has a very complex color. At the same time, the HPS affects the eyes extremely tediously. Conventional fluorescent tubes remain between 60-80 CRI, but it is also possible to get fluorescent lights with a CRI of 90+. For LEDs, the minimum CRI is about 20, but it’s not very common. The standard for mass production is the CRI 80 for LEDs, but today there are also LEDs with massive CRIs of up to 97.

Fourth, high-quality LED lights are even safer because they do not contain harmful chemicals. Unlike many other light sources (e.g., fluorescent lighting), LEDs do not emit harmful UV radiation.

Fifth, the quality of high-quality LED lights is considerably longer. If the lifetime of fluorescent light bulbs is between 15,000 and 20,000 hours, then LED lights will, under normal conditions, be 50,000 to 100,000 hours, depending on the type of LED. The life of the metal halite is about 10,000 to 12,000 hours and the lifetime of HPS is up to 24,000 hours.

Additionally, in addition to longer working hours, the luminous efficacy of LEDs is also significantly improved compared to conventional light sources. If the average fluorescent light retains about 70% of the initial approx. 15,000 operating hours, then better-quality LEDs will retain over 90% of their original luminous efficiency after 60,000 hours of operation. It also has a significant advantage in terms of power consumption, since there is no need to significantly overcomb light the room to provide the required light level during the life of the luminaires. It is also important to know that turning off the LED light does not adversely affect the life of the luminaire. Most LED lights are also shockproof, which allows them to be successfully used in places where older technology lights are not supported.

To sum it up, as shown above, LED lighting has now become the most competitive light source in almost all operating environments. There are still some niche areas in which we can talk about traditional light sources, but such operating environments will continue to be diminishing rapidly. If you also consider installing LED lights in your company, please feel free to contact!

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