Facilities and properties everywhere are switching to more efficient lighting technology. Older lighting technologies such as metal halide, high pressure sodium (HPS), or even fluorescent are slowly becoming obsolete and being replaced with evolving solid-state lighting technology.
With a strong focus on the energy savings promised by a lighting system, its lifespan often gets overlooked. Along with the direct energy savings that an efficient lighting technology such as LED offers, facilities are also realizing cost savings by prolonging their lighting system through best practices.
These best practices involve both physical applications and practical decisions. The following five strategies will lay the foundation for a lighting system that can realistically last 50,000 hours or longer versus 15,000 hours, which is very common with high-intensity discharge (HID) technologies.
1. Choose the right technology
All else equal, LEDs offer the longest rated lifespan compared to commercial application lights such as metal halide, HPS, and fluorescent. When a facility adopts LED, their lighting system is set up for a lifespan of two to three times the lifespan of other lighting technologies.
From there, facilities with LED fixtures can take steps to extend the lifespan of their lighting system from 50,000 hours all the way up to 100,000 hours in some cases, which improves the ROI. The steps commonly taken to prolong the lifespan of a lighting system apply no matter what technology is being used.
2. Match the product to the environment
Issues occur when a lighting system specifically designed for one environment is used in another. For example, lights that aren’t built to handle vibrations are much more likely to fail prematurely when used in high-vibration locations. Similarly, lights that are not vapour tight and do not lock out any water, dust, or dirt will likely fail prematurely when used in wet locations.
Applying a light in an environment for which it was not designed or made specifically can prove detrimental to the lifespan of any light, not just LED. If a light must be applied in an atypical environment, use a specific technology or casing, which can be sourced from a reputable commercial lighting company that offers different application-based light fixtures.
3. Look for properly designed heat sinks
Heat can weaken a light’s lifespan if the heat sinks commonly used for thermal management within a lighting fixture are improperly designed.
Excess heat is often conducted away from the junction box through a heat sink. This allows the heat to escape from the light, which prevents damage. Heat sink design, by nature, is an intricate process. Improperly designed heat sinks can cause issues such as air pockets and less-than-optimal cooling, putting the light at risk of premature failure.
The issue of lighting fixtures generating heat will persist until lighting companies and engineers find a way to use 100 per cent of the electrical input to produce light rather than heat. For now, it can only be dealt with by using properly designed passive cooling methods and choosing a technology that is efficient in turning electrical input into light rather than heat.
4. Dim below capacity for longevity
As important as it is to use lights in their intended application, using an overqualified light below its capacity by dimming is a common way to extend a light’s lifespan.
For example, dimming a light with a capacity of 150 watts down to 125 watts will reduce stress on the light. Operating the light well below its capacity will ensure its limits are never tested and thus prevents potential damage from excess heat.
Heat-withstanding capacities aside, a light operating below its standard output also reduces stress on its use. For example, a light using 150 watts could last for five to six years operating 24 hours a day. All else equal, that same light operating at 125 watts at 24 hours a day may last roughly an extra year.
5. Maintain consistent lumen output
All luminaires output less light over time, in a process called lumen depreciation.
There are two common ways to compensate for this depreciation in any lighting system. The first is to adopt LEDs, which depreciate less overall and more slowly. The second is to dial the light fixture below its maximum output to start and slowly dialing it up to remain at a consistent lumen output level throughout its lifespan.
Many up-to-date lighting systems use these tactics to prevent under-lit areas, even near the end of a light’s lifespan.
By following these best practices, facility managers, building owners and electrical contractors can ensure their lighting systems meet or exceed lifespan expectations originally promised by LED technology.
Dwayne Kula is the founder of My LED Lighting Guide, which specializes in industrial and commercial LED lighting. He can be reached at (888) 423-3191.