Factors That Affect The Lifespan of Lights

One of the benefits of the LED is its long lifetime. Because they have no movable parts or filaments that may break, LED’s can have long lifetime. The light output from all light sources, LED, halogen, metal halide and fluorescent decreases over time. The amount of light from the light source at a specific time in the future is referred to as the lamp lumen maintenance factor, or LLMF. The lifetime of a LED module is defined as the time it takes until its light output, or lumen maintenance, reaches 70% of the initial output. This is also called L70. In other words, the module does not die instantly as many conventional light sources do, it slowly dims down. Lighting planners take this effect into account when they dimension the lighting installation. As they want the light level to reach a minimum lux value at the end of the lifetime, they over-dimension the luminaire installation, often by using more luminaires. Therefore, the lux value in the beginning of the operating life of the lighting installation is higher than what it is at the end. The luminaire industry has standardised LED lifetime to L70 = minimum 50000 hours, which corresponds to an LLMF of 0,7 as long as the lifetime of the lighting installation is set to the same amount of hours.

Factors that affect the lifespan of lights:

Overheat

LED lights normally have metal heatsinks to draw the heat away from the LED chip itself. If the heat sink is not adequate in size, poorly connected or of a poor design the LED can overheat and fail very rapidly. The same applies to degradation of the driver electronics.

Output of the LED

Within an LED there is an ‘active region’, where a process called radiative recombination occurs and light is produced. If the material used in this active region has an existing defect, it will be worsened by heat and electric current. Eventually, this leads to a decay in the output of the LED. This issue is avoidable if the manufacturer chooses an LED which will exceed the expected lifespan of other components used within the bulb itself. In order to maximize the length of time that the LED lights you buy last, check the LED component choice on the bulb’s datasheet to be sure that it’s of a high enough quality.

Poor components

Incandescent lights are simple, they are basically just a thin metal filament. LEDs are more complex. Capacitors and other components are normally required as part of the power supply regulation and conversion of AC current into the low voltage DC current required by the LED. While the LED itself might have a life span of more than 10 years, other components might not. Electrolytic capacitors in the ballast of LED luminaires are a known limiting factor of a luminaires lifetime due to their low tolerance for elevated temperatures. These components can be internal or external to the LED depending on the light.

Fitting type

LED retrofit designs with bayonet, edison, gu10 and mr16 fittings are all designed for AC supplies. This requires a greater amount of electronics housed within a compact, heat-sensitive product. The volume constraints of these designs can limit optimal component selection and thermal management and render it unserviceable in the event of failure. LED kits with external drivers have the advantage of generally better thermal management and isolating the most likely source of electronic failure to the driver unit, rendering servicing simpler and cheaper.

Environmental factors

Higher than expected ambient temperatures in a roof space, lack of airflow around the heat sink or poorly regulated mains power supply can be detrimental to the life of a LED. Too much heat is probably the #1 killer of LED lights.

How long do LED light really last?

Unfortunately, there is no simple answer to this question. The lifespan of LED light lights depends on several key factors, but generally speaking the range is anywhere between 10,000-50,000 hours. That’s a big range, but it means that your LED bulb could last up to 10 years, depending on how extensively it’s used and the conditions it’s used in. While we can’t definitively say how long a bulb will last for, LED lights are still much longer-lasting than their traditional counterparts, as seen in the table below. To maximize the lifespan of the LED lights you install, be sure to watch for: Components: Choose LED lights with good component choices and install with appropriate power supplies. If your LED lights are short-lived, check your light fitting for variations in voltages. Environment: Install LED lights in appropriate environments with good ventilation to allow cooling. Try to avoid installing near sources of heat. LED lights are fairly complex little pieces of technology, so it makes sense to invest in the highest quality products from LED manufacturers with a proven record. Do this, and you’ll be sure to install a lighting solution that will stand the test of time.