Light-emitting-diode (LED): a semiconductor diode that emits light when an electric current is applied in the forward direction of the device, as in the simple LED circuit. The effect is a form of electroluminescence where incoherent and narrow-spectrum light is emitted from the p-n junction in a solid state material.
Sound a bit confusing? You’re not alone. This holiday season, LED lights have been at the forefront of decorating discussions. But how much do you really know about this technology? One thing that we’ve all heard is that LED lights are more energy efficient than other types of lighting. In the correct application, this is true. So, energy efficiency, logic has taught, must mean more cost efficiency. Well, maybe.
Decking the halls with LED
Let’s take a closer look at this new twinkling technology. Your holiday decorating lights are one application where LED is more energy efficient and cost less money – less than a 5 year pay back. Tables 1 and 2 indicate the usage required for standard vs. LED lights. The information is based on 100 feet of Christmas lights lit for 8 hours per night for 38 nights. The usage cost is calculated based on Louisville Gas & Electric’s 7.3 cents a kilowatt/hour rate. LED lights are the overall winner. (Numbers may very with actual cost due to sales and clearances.)
String of M5 Type Lights (100 feet of lighting)
LED Christmas lights can also provide a greater range of control. In some cases, 43 sets of LED lights can be connected end-to-end (43 for icicle, 3 for C7 type lamps), use much lower wattage (less heat and cool to the touch), the light’s colors will not fade or flack, the epoxy plastic is virtually unbreakable and they are listed to last 25,000 hours. Plus, with red lamps, blue lamps, green lamps and the correct electronics you can produce over 16 million colors and dim the light as needed.
Icicle Type Lights (100 feet of lighting)
So you know LED lights are clearly a bright sustainable solution for holiday decorating, but how is this technology used elsewhere?
LED: Shining a light on public safety
At Luckett & Farley we’ve been specifying and seeing LED lights for years, even before the Energy Policy Act of 2005 (EPACT 2005). Currently, we have specified LED recessed lights to task light the nurse alcoves for our VA Medical Center project in Decatur, Georgia, and of course the exit signs. As of January 1, 2006, EPACT 2005 states that all exit signs must use less than 5 watts per face as indicated by the ENERGY STAR Program Requirements for Exit Signs, Version 2.0. Version 3.0 lowers the requirement to less than 3 watts. Luckett & Farley is also using the same technology to help save lives. New building designs incorporate LED lights for directing people in an emergency evacuation for a quick and safe exit.
The first LED EXIT signs were introduced in 1985. In the early 1990s, a spec-grade LED exit sign cost around $200. Today, these signs are a much improved specgrade die-cast aluminum fixtures costing only $65.
While there is a clear advantage for energy efficiency and versatility, the current price barrier of LED lights may make some clients hesitant to fully embrace the technology for their facilities. However, LED technology is progressing rapidly and manufacturers are creating light fixtures specifically designed to direct LED lighting more efficiently. Outside of decorative lighting, task lighting, and dimming downlights, the fastest growing area where LED lights are being used is in parking lots. Parking lots that require lighting throughout the night have the best payback. As the process advances, pricing for these fixtures is predicted to fall in-line with standard light fixtures as the movement toward high-efficiency lighting becomes the new standard, which promises to make every season a little greener.