By Vicky Broadus
Advances in light-emitting diode (LED) technology mean facilities no longer need to accept lighting elements that are difficult or expensive to maintain. LED fixtures have become increasingly affordable on the front end, especially when combined with utility rebates. Once installed, the technology’s energy efficiency, longevity, and reliability can significantly reduce both power and maintenance costs. As a result, many business owners and facility managers across Canada are choosing to retrofit their facilities with LED.
Out with the old
Identified by their distinctive round-shape bulbs, metal halide systems are still common in factories and warehouses, but they are not the most energy-efficient option for such places.
An example of a high-intensity discharge (HID) light, metal halides work like fluorescent lights in some respects and incandescent bulbs in others. They pass an electrical arc through a gas-filled tube like a fluorescent, and the arc itself creates bright, visible light, like an incandescent. However, the process is not efficient—about 75 per cent of the energy metal halides consume is wasted as heat. Further, since they are a 360-degree light source, for focused, directional applications, much of the light they produce goes where it is not needed.
Brightness is one of the selling points of metal halides. The 400- to 500-watt bulbs, most common in high-bay fixtures, can generate 25,000 to 35,000 lumens when first installed. However, lumen depreciation occurs quickly—a metal-halide bulb’s light output typically decreases by half within two or three years. (More information can be found in The Lighting Handbook 10th edition, published by the Illuminating Engineering Society [IES].)
The other common industrial and commercial lighting technology is fluorescent lighting. While fluorescent fixtures are not nearly as power-hungry as metal halides, they have some drawbacks. Like metal halides, fluorescent bulbs are a 360-degree lighting source, which means the ceiling receives much of the light they produce. Similar to metal halides, they also have ballasts needing regular replacement. They do not take well to the cold, which can be a problem in unheated areas during winter. There are also fluorescents’ well-known issues like flickering, yellowing, humming, unintentional dimming, and burnouts. LEDs have a driver, but they typically have a longer lifespan than fluorescent ballasts. They also do not have bulbs that need replacement, like other kinds of fixtures.
In with the (somewhat) new
For half a century, LEDs have been used for small indicator lights in consumer electronics like computer keyboards and telephones. These devices employ semiconductors and electroluminescence to create light. Electrical current provided by a driver passes through a microchip, which illuminates the tiny diodes. Due to LEDs’ low heat production, negligible energy use, long life, and durability, they were prized for enclosed devices not intended to be opened and tinkered with.
Only in the last decade has technology advanced and prices dropped to the point where LEDs can provide bright, affordable light for spaces as large as service centres, factories, and warehouses. In fact, the variety of LED fixtures and the light they produce has developed so rapidly they are now an option for virtually any type of residential, commercial, or industrial construction.
Besides their energy efficiency, brightness, reliability, and longevity, LEDs offer the advantage of being fully customizable, from light distribution and colour temperature to controls. Occupancy sensors and zoning add to their efficiency. When outfitted with sensors, LEDs can even respond to daylight for further savings.
A good manufacturer with an applications-engineering team is the best source of information on everything involved in outfitting and retrofitting individual spaces. They take down measurements, look at existing fixtures, and provide a detailed proposal based on the square footage, the ceiling height, and the client’s overall goals—for some, it is energy savings; for others, it is increased lumens or foot-candles. The manufacturer can recommend the appropriate light temperature for a space, from a warm 3000 Kelvin—ideal for settings such as restaurants—to the bright, white 5000-K light suitable for warehouses. A good lighting manufacturer can also assist with researching and securing utility rebates.
Though the purchase price of LEDs is rapidly decreasing, they can still cost up to three times as much as other forms of lighting on the front end. Therefore, it is important to ensure they are the right technology for the facility.