Why LEDs Continue to Dominate Lighting Conversation
June 17, 2016 - Lighting
By Tom Higgins, Technical Communications Director, Revolution Lighting Technologies
Every so often an invention comes along that completely disrupts the technology of its day. Like the steam engine did to the horse, and Edison’s electric light bulb did to the gas lantern, solid-state LED lighting has ushered in a new era of unprecedented opportunities and capabilities for institutional and commercial facilities.
Most facility managers, architects, and lighting designers already recognize the higher efficiency that LEDs deliver when compared to legacy lighting options such as incandescent, halogen, and fluorescent. It’s no secret that watt-for-watt, LEDs pump out more light than conventional lamps do. When held against the customary performance standard of lumens-per-watt (lm/W), most LEDs are five to seven times more efficient than incandescent bulbs, twice as efficient as compact fluorescents, and 30-40 percent more efficient than standard fluorescents. And every month brings fresh advances in LED efficacies. For example, LED products with efficacies approaching 200 lm/W have recently become commercially available for general lighting applications — nearly twice the efficacy of the most efficient fluorescents.
But efficiency only scratches the surface of what modern LEDs have to offer. Their solid-state construction also makes them tough and durable, where lifetimes of 50,000 hours are typical, and 70,000 hours or 90,000 hours are not unusual. In fact, LEDs last so long that their lifetime is measured not by the average time to failure, but rather by how long it takes for the light output to drop to a certain level. That’s because LEDs seldom fail catastrophically like conventional lamps do.
Long lifetimes translate into money-saving, maintenance-free lighting installations, which can mean big savings, especially for large buildings with high ceilings or for outdoor lighting. Many large facilities, hotels, and whole cities have converted to LEDs for this reason alone. The city of Los Angeles now reaps an estimated $2.7 million per year just in maintenance savings after switching to LED street lighting. L.A. invested $57 million to replace 140,000 streetlights and expects to recoup that investment in seven years with the money it saves on energy and maintenance. Large commercial or industrial facilities will often recoup the costs of an LED retrofit in less than two years, depending on local energy rates.
Beyond energy and maintenance savings, solid-state lighting offers other strategic advantages. Chief among these is controllability. When paired with compatible lighting controls, LEDs can meet the specific illumination needs of virtually any application and can cut energy costs even more. For example, many of today’s LED lighting products are fully dimmable using a variety of conventional dimming protocols, such as standard wall-mounted triac switches, low-voltage 0-10VDC signals, PWM, DALI, MIDI, and DMX, along with other, less conventional dimming methods. Occupancy sensors add another layer of energy-saving control as well. Moreover, these lighting-control strategies can be implemented with either wired or wireless devices.
Because LEDs are basically light-emitting semiconductors, they are also uniquely suited for our electronically connected world and the so-called Internet of Things. LED luminaires can actually talk to one another and report on their status to a remote central control. An entire city-wide or campus-wide network of LED streetlights, for instance, can now be monitored and controlled from a single laptop computer.
The last couple of years have seen the brisk development of networked LEDs and lighting controls with extraordinary functionalities. Recent work has focused on transforming solid-state lighting fixtures into communications nodes for an interconnected network of “smart lighting,” or “LiFi.” These systems enable each LED fixture to communicate directly with a cell phone or PDA, thereby enhancing a customer’s shopping experience in a shopping mall or a patron’s visit to a museum while also lighting the space.
All of these developments and others point to a technology that is revolutionizing the lighting industry and poised to one day dominate it. The question is no longer if but when to upgrade. As the cost of LEDs continues to drop and their capabilities continue to advance, however, the cost of waiting rises. Fortunately, today’s LEDs can now meet the demands of any lighting application at a reasonable cost and an attractive ROI. There are even LED tube lamps that work with existing fluorescent ballasts, making it easier than ever to join the revolution.
Tom Higgins is Technical Communications Director at Revolution Lighting Technologies, Inc. and has more than 40 years of experience in electro-optics technology.