Product life-time and maintenance
Incandescent lamps have been phased out just because their replacement was much longer lifetime (and higher efficiency) of fluorescent lamps. The fluorescent lamps can indeed last well over 10-thousand hours but older ones deteriorate rapidly when turned on and off frequently. This factor has to be taken into account when designing lighting systems that use fluorescent lamps.LED lighting has none of these drawbacks all the while having much longer lifetime of 25-thousand to over 50-thousand.
When incandescent lamps have been phased out one of the reasons for their replacement was much longer lifetime (and higher efficiency) of fluorescent lamps. The fluorescent lamps can indeed last well over 10-thousand hours but older ones deteriorate rapidly when turned on and off frequently. This factor has to be taken into account when designing lighting systems that use fluorescent lamps.
For example, connecting a presence or motion detector to a fluorescent lamp in a corridor (usually to cut down energy costs) might be a bad idea from the lamp lifetime point of view. If the corridor is used intermittently yet frequently, the lamp will demand frequent maintenance and replacement.
LED lighting has none of these drawbacks all the while having much longer lifetime of 25-thousand to over 50-thousand hours. Many of the early LEDs from 1970s are still functional. Failure ratio is also much lower with LEDs than with other lamps. LEDs are solid state light source, meaning that mechanical deterioration does not apply to them.
The maintenance costs do not depend solely on the lifetime of a lamp. It is a significant part of the costs, as newer technologies are more expensive, but it is not the only part. Frequent replacement of fluorescent lamps may also mean smaller revenues: an office or retail space has to be closed down when maintenance and replacement take place.
Heat radiated by fluorescent lamps can also negatively affect lifetime of a luminaire, increasing refurbishment costs. And the fluorescent lamps have to be disposed of safely due to mercury content, requiring yet more effort when replacing them. Again, none of these drawbacks apply to LEDs: maintenance is much less frequent due to long lifetime, they do not require special treatment when replacing them and their heat radiation is negligible.
When designing a lighting solution for a certain environment, all these factors should be considered. An all LED solution might seem costly but it will save maintenance costs. LEDs can be used with automatic controls, reducing the necessity of manual switching, which is yet another area of maintenance. Moreover, LEDs are more energy efficient and can decrease energy consumption even further in conjunction with daylight sensors.
If a fluorescent lamp solution is used anyway one should not forget to add labor costs to the maintenance expenses. During the lifetime of an average LED lamp the fluorescent one has to be replaced two or three times. This requires a janitor, a ladder, correct disassembly of the luminaire, their cleaning, replacing of the lamp, and the re-assembly. In many environments the surrounding area has to be emptied, further adding to the discomfort of the employees. Regardless of having an own janitor or paying for maintenance as an external service these labour costs can be higher than the price of the lamp itself.