Brightening your home with LEDs: Should you buy, or should you wait?
More and more people are looking towards LED light bulbs as a technique to conserve energy. But will you really get the best savings by focusing on this still emerging, costly alternative now? Or is it better to save your money for the time being, or to spend your money now other energy-efficient lights, and use the money you save in electricity to buy LED house lights down the road?
You have most likely seen LEDs already: camping headlamps, LED Christmas tree lights, wind-up emergency torches. What about LED house lights? If LEDs use so little energy, why aren't manufacturers scrambling to sell LED lights for the home, and why aren't consumers scrambling to buy them?
I won't try to advocate for LED bulbs as a way to address rising electricity expenses or as the most ecologically beneficial lighting solution around. Truth be told, I think LEDs have a ways to go yet, in terms of light strength, quality, and cost. There are some LED products you should invest in now, such as LED Christmas lights. And you may enjoy experimenting with a few LEDs, if you're the hands-on type. But you are going to save more money by keeping with your current lights, and switching to fluorescent lighting in the short term. Compact fluorescent lights, or CFLs, have a payback so short that they'll pay for themselves before LEDs have matured enough to render CFLs out of date.
LED lights are more energy efficient than incandescent or fluorescent bulbs. However LEDs have very directed light. An incandescent bulb casts its light over a wide area quite equally, while LEDs are quite focused, so that the space they directly illuminate is quite bright, while the further from the direct beam, the fainter the light. For LED Christmas lights, that isn't a problem; you just want some shining points of light, which LEDs do very well. But an incandescent or CFL will do a much better job of lighting your living room than an LED light in the same fixture. The light will be more broadly distributed, and with a warmer color.
When you see LED manufacturer claims of LED light output, you should be suspicious. A rating in Lumens, which indicates brightness, is misleading for LEDs, because of their direct beam. Lumens levels are read from a photo sensor placed right below the light. A household LED bulb at 2 watts might have the same lumens rating as a 50 watt incandescent bulb, or as a 15 watt compact fluorescent, but the LED lamp may only send a narrow beam directly beneath it to the sensor, while the incandescent light and compact fluorescent will light up a much broader area, and still give that same lumens measurement for the area immediately beneath the bulb. This could be the source of a recurring complaint among LED buyers, for example: "The packaged said this 2-watt LED bulb has the same light output as a 50-watt incandescent bulb but it looks closer to a 30-watt incandescent if you ask me."
When it comes to halogen lights, they are no more efficient than incandescent lights, so the same efficiency considerations apply here. But because halogen lights are typically more direct than incandescent bulbs, LED lights that are designed to replace halogen lights are both more efficient than the halogens they replace, and up to the task of direct lighting that halogen bulbs provide. You can buy LED replacements for the more common halogen bulbs such as GU10 and MR13, and here's where you may want to start converting to LEDs.
LED house light manufacturers work around the issue of the narrow beam of a light emitting diode, by designing household LED bulbs that are a collection of individual LEDs, with each LED directed at a distinct angle, so that a wider area is highly illuminated. This increases the area of good light provided by an LED light. But very few such bulbs provide the breadth of area coverage of traditional incandescent bulbs or CFLs and at the same time match their total light output.
Where LED lights are an improvement over existing bulbs is as replacements for lighting that is (or should be) highly directed. For example, a light in a narrow hall, where the chief purpose of the light is to show people their way down the hall, would be a good use of LEDs.
Task lighting is another area where LEDs do well. Why light up your entire work room if all you need to see is what's on the work bench right in front of you? A couple of LED bulbs hanging above the work area will do the job beautifully. But this won't be cost-effective unless you spend hours every day in the workroom.
LED light bulbs are, according to their makers, very reliable, when compared to incandescent bulbs and CFLs. LED bulb life ranges from 35,000 to 200,000 hours, compared to 1,000 hours for an incandescent light, and 8,000 hours for a CFL. But I have seen consumer ratings of LED lights that suggest some bulbs die within a few weeks of being switched on. Clearly there are quality problems still to be resolved - yet another good argument for holding off a couple of years before switching wholesale to LEDs.
Whether LEDs will really fulfill their long lasting billing is an open question - even the 35,000 hour ones would need to be on 24x7 for 4 years before they come close to reaching their advertised range. And LED lights do dim with age - so while a bulb may be rated for 35,000 hours, it won't shine with its starting brightness for the full 35,000 hours - the closer to the end of its expected life, the less light it will emit. LED lights do slowly fade in light intensity and therefore in efficiency, although they will remain more efficient than either CFLs or incandescent bulbs throughout their life.
The "color temperature" of a light source, measured in 'degrees Kelvin', determines how we respond to its light. You are probably used to the yellowish glow of incandescents at around 2800 Kelvin (2800K), even though fluorescent lighting is closer to the natural daylight temperature of 6000K. Any LED bulb with a color temperature of 6000K or higher will tend towards bluish, and any LED with a color temperature above 4000K will appear whiter than an incandescent.
Although homeowners are often worried about how fluorescent or LED lights can make their rooms look blinding white instead of the soft yellow glow provided by incandescent lamps, remember that a little sacrifice in color temperature will really help reduce your energy bill. Be a leader - convert your lights to true daylight colors, whether with CFL lights or LEDs. You will be helping your family and friends to make the change, when they find out they won't be the only ones with a slightly bluer light tinge in their homes.
Whether you switch some of your lights to LED lights now, or let the technology and reliability get better, you can rest assured that LEDs will play an increasing role in lighting our houses in the future. In my opinion it makes sense to wait, except in certain special use lighting situations where the highly directed, focused light of LEDs is what you need, and where you have money to spare. If you just want to save money - or to cut your energy use for environmental reasons - the same amount of money spent on CFLs, or most other energy efficiency upgrades, will reduce your energy costs and carbon footprint more than buying the LED lights now available.
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