New technologies in outdoor lighting, such as LED lamps, redefine the way we work, and also the way we need to think about outdoor lighting. And one of the things we now have to think about is how to best plan the ideal end of life of such lamps.
We do have to realize that with the advent of new light sources such as LEDs for outdoor professional lighting, new challenges face specialized manufacturers in outdoor lighting, Philips Lumec being one of them. One of those challenges is first and foremost ensuring a safe level of lighting at all time, even if the LED lamps do not die below at a certain level as others do. For example, high pressure lamps die at more than 50 % of their light emission.
That being said, it is difficult to signal the end of lamp life with the new LED lamps. As mentioned before, they have an extremely long lifetime. Also, contrary to other types of lamps, LEDs do not completely extinguished after a certain number of hours. The lamp emits less light until it reaches a minimum level of illumination. LEDs, in fact, gradually reduce their flow until they reach less than 1 % of light.
In that perspective, here is a question we, as professionals in outdoor lighting, need to ask ourselves: How can we identify the end of a “useful” and secure life of a LED lamp on a street light so that it is replaced with a new one? Because LED lamps show absolutely no sign that their useful lifetime use is reached, they cannot be replaced as planned in the initial photometric study, and thus reduce light levels below the minimum level established that will guarantee the safety of the people that need it and depend on it.
Several options can be used, but they might not suit everyone. Among them, one possibility is to turn off the lamp when the lifetime is reached. As the old models of lamps do, why not keep the same clear and compelling evidence for maintenance?
Another option could be to flash the light when it is put into function. Residents could then complain to the city due to a “visual discomfort”.
But we also need to ask ourselves, as professionals in outdoor lighting, what would happen in remote areas? We could perhaps repeat the flashing all night, but is that a safe and wise solution? Or perhaps flashing very fast (with ten cycle per second, for example), something that can be felt but that does not diminish the lighting of the lamp on the ground?
Maybe this is where Dynamic controls will be really useful. With remote management tools, we will be able to anticipate when and when to proceed maintenance on LED lamps.
We are curious to know what your thoughts are on that phenomenon. Tell us what you think would be the “ideal” end of life of a LED lamp. Because it is a challenge that concerns us all.
Do not forget that we, as a community of professionals in outdoor lighting, need to share our knowledge in order to come up with the best and safest solutions for the people we work for and serve, whether it be citizens, cities, constructions firms, architects and so on. So please, do not hesitate to share your ideas with us.