LEDs make big claims about savings potential (up to 90-per-cent energy savings compared to other lamps, such as fluorescents, HIDs, etc.). But how much of this is marketing hype?
There are LEDs that hold true to the financial and energy savings they promise. But LEDs are only worth the investment if they actually do what they say they can.
The industry standard for LED lamp failure is three per cent. But many building owners and facilities managers are experiencing failure rates of up to 20 per cent or higher. With a failure rate that high, 20 out of every 100 lamps purchased can be expected to fail and require replacement. (And the failed lamps will likely be scattered throughout a building, adding to the amount of time it takes to replace them.)
High failure rates occur for several reasons, but can often be attributed to a few factors. Here are four reasons LED lamps fail — and ways to prevent it.
1. Use of poor-quality materials
Commercially available LEDs comprise several components; LED performance is typically a result of how these components work together. From the type of lens to the heat sink and the chips and power supplies that generate light, LED components must be built to last if the lamp is expected to function properly and provide acceptable light output.
Quality materials matter; if a lamp doesn’t have them, failure is likely. Take LED drivers, for example. A driver converts AC power into DC power so an LED can operate. (Incandescent lighting operates using either AC or DC power, but LEDs must obtain power from direct current.) If poor-quality components are used to construct the driver, the LED may fail — requiring the purchase of a new lamp to replace one that was supposed to last for years (or decades). If the correct driver isn’t used, the heat generated by the driver may be difficult to dissipate and cause failure. This is often why LEDs flash or flicker — it’s an early sign of driver failure.
What are indicators that an LED lamp is made of quality materials?
- LEDs that offer sufficient heat dissipation may weigh (and cost) a little more.
- Ask about chip size; a larger chip provides more light and good stability against current variations while smaller chips provide less light and poor stability.
- Examine the lamp’s paint or powder coating; if it’s not well applied, the other components (the ones that aren’t visible) are likely cheap and thrown together quickly.
2. Inadequate lamp testing
Ask the manufacturer about its LED lamp-testing procedures. Some manufacturers fully test completed LED lamps before shipping.
For up to 10 days at a time, diligent manufacturers will place LED lamps and fixtures in a specially designed room and test them by repeatedly turning them on and off, and by leaving them on for extended periods of time.
As solid-state electronic devices, LEDs are similar to TVs or other consumer electronics: They tend to fail early if they’re going to fail at all. By properly testing LEDs, manufacturers can catch failures before the lamps are shipped.
3. Temperatures are too high (or too low)
When installing an LED in an enclosed fixture, check the lamp first. LEDs shouldn’t be placed in tightly enclosed fixtures unless they’re approved for enclosed spaces. When heat can’t dissipate from the heat sink, it can cause lamps to fail prematurely.
Also keep the surrounding environment in mind. The hotter the room is, the earlier an LED light may degrade. Why? Because LEDs emit light that decreases exponentially as a function of time and temperature.
Adequate thermal management is key to making sure that LEDs will last in hot environments. LED lamps are available with extra-low thermal protection, which helps them resist cracking due to cold temperatures.
4. Lamps are counterfeit
Some LED lighting products are made to look similar to reputable brands, sometimes even using identical markings, part numbers, logos, and packaging. These cheap imitations are often developed and designed without regard for patents, trademarks, or safety.
How is it possible to determine whether an LED lamp is what it claims to be?
Verify its Underwriters Laboratories (UL) mark.
A UL mark means the LED has been tested, inspected, and validated for safety. But just because a product has the UL mark doesn’t mean the mark is real. Some LEDs carry a counterfeit UL mark, or a UL registration number that doesn’t belong to that manufacturer or product. Verify the UL mark by visiting the free UL Online Certifications Directory.
Confirm a Design Lights Consortium (DLC) Qualification.
A project of the Northeast Energy Efficiency Partnerships, DLC is a non-profit organization created with the goal of preventing LED lighting failure. Commercial LED luminaires, retrofit kits, linear replacement lamps, and E39 screw-base and other LED replacement lamps qualified by DLC have been tested and evaluated to specific performance requirements. They are manufactured with high-quality components, held to such high standards that a five-year warranty is offered on the LED products as a symbol of their quality.
Make sure lamps last by following the guidelines listed above. Reduced replacement time and costs, decreased cooling loads, lower risk of electrical shock during replacement, and 50 to 90-per-cent savings on lighting energy are all possible with high-quality LEDs.
Jody Cloud is a lighting consultant who is officially certified to offer continuing education credits in LED lighting to members of the American Institute of Architects, the Building Owners and Managers Association, the American Hospital Association, the Professional Retail Store Maintenance Association, and Community Associations Institute. He is also owner and founder of YES LED Lighting, as well as the author of the bestselling book Say YES to LED Lighting. He can be reached at firstname.lastname@example.org.