Why I love LEDs, by Anna Hackman
How many of you want to switch out your current light bulbs to LEDs, the new cool lighting technology on the block? Maybe you hate the color of your CFLs. Perhaps the thought of mercury in your CFLs gives you the willies. Or maybe your incandescent laden home with its high energy bills are burning a hole in your wallet. For whatever reasons, LEDs have a bright future.
Why do I love LEDs? Since 2007, I became a convert to the LED technology when my eyes saw LED Lighting Fixture’s LR6’s downlight, (Cree has since bought the company.) The color was wonderful, the output was great, and best yet, I can say good bye to my energy hogging incandescent light bulbs and my ugly colored CFLs. I have been a smitten puppy ever since.
The problem that I see with this new technology is the average Joe or Josephine really doesn’t understand what LEDs are all about. Reading the Department of Energy’s Solid State Lighting website can give you a headache. So, let me shed some light on why LEDs may be in your future, highlighting both the advantages and disadvantages of this new technology.
What is LED technology?
LED stands for light emitting diode.
“Basically, LEDs are just tiny light bulbs that fit easily into an electrical circuit. But unlike ordinary incandescent bulbs, they don’t have a filament that will burn out, and they don’t get especially hot. They are illuminated solely by the movement of electrons in a semiconductor material, and they last just as long as a standard transistor.” [Source]
The Advantages of LEDs:
One of the advantage of an LED is its efficiency. The filament of an incandescent bulb must be heated to generate light. This results in a lot of wasted heat. Worse yet, only 10-15% of the electricity consumed results in the light you see. LEDs on the other hand use a higher percentage of the energy used to create its light.
According to the Department of Energy, LEDs have the longest life compared to the following traditional lighting:
If you have a high ceiling, LEDs could be a godsend for you. Since their life expectancy is anywhere from 35,000 to 50,000 hours, you wouldn’t have to change hard to reach lights for a couple of years.
One of the biggest concerns about fluorescent bulbs is that the bulbs contain mercury. CFLs contain on average 4 milligrams of mercury. If the bulbs are broken, mercury vapor is released. Mercury is a potential neurotoxin, and therefore especially dangerous for children and fetuses.
In addition, mercury can leach into our waterways when bulbs are disposed into our landfills rather than recycled. According to Association of Lighting and Mercury Recyclers,
“[g]eneral belief is that most of the breakage occurs in the container, as opposed to at the landfill, due to the fragile glass and compacting that occurs in containers. When these containers are also exposed to moisture from rain or other sources and they leak, or when they are washed out, mercury enters the environment. Studies have shown that when fluorescent lamps break in containers the mercury can hover for days, and eventually migrate downwind and back onto the land,.”
To put the mercury issue in perspective, the use of fluorescents over incandescent bulbs dramatically reduces mercury emissions from coal fired electrical plants. A worse case scenario according to Energy Star, the broken florescent bulbs could ”add 0.12 metric tons, or 0.12 percent, to U.S. mercury emissions caused by humans.”
But in my mind, that small percentage is still a concern especially when there is another lighting option available. Recycling all fluorescent bulbs should be mandatory. (You can recycle your CFLs at Home Depot, Lowes, and Ikea. See here for a list of lamp recyclers near you.)
Can be used in Cold Temperatures:
Fluorescent lamps and cold temperatures are not a mix made in heaven. In order for florescent lamps to work in cold temperatures, the amalgam added lamp will take longer to brighten up. In contrast, LEDs performance increases as temperatures drops, making it an ideal candidate for use in refrigeration.
One of my biggest complaints about fluorescent bulbs is that they have to warm up before they reach their full brightness. LEDs on the other hand, warm up instantaneously.
Turning on and off fluorescents lessens their lifespan. According to a report by Rocky Mountain Institute in 2008,
“A study published in 1998 examined CFL performance for five different operating cycles. It found that when the length of time the lamps were on was reduced from 3 hours to 1 hour, the lamp lasted for 80 percent of its rated life. When reduced to 15 min and 5 min, the lamp lasted for 30 percent and 15 percent, respectively, of its rated life.28 ”
Keep in mind: although turning off the bulbs may lessen their life, in most cases, the reduction in energy cost outweighs the bulb replacement. (See this discussion of how to ascertain your energy savings from turning off your fluorescent bulbs.) However, the advantages of LEDs are you can turn them off and on without shortening their life. Just think about a traffic light which has LED bulbs in it. Notice how the light’s constantly turning off and on?
Disadvantages of LEDs:
I would be remiss to not point out that there are disadvantages to LEDs. My issues with LEDs are as follows: Price, Heat, and of course, the Marketing Hype.
Recently I reviewed Lighting Science’s 60 watt comparable recess light bulb sold at Home Depot. Although I loved the white halogen type light, would I splurge for multiple bulbs at a price tag of $40 a piece? I figured the payoff would be about 4 years compared to a dimmable CFL. However, prices are falling. When I fell in love with the LR6 downlight in 2007, the cost of the bulb was $125! In a September, 2010 GreenTech Enterprise article, Bill Watkins, CEO of Bridgelux, predicted prices will continue to fall dramatically.
“To outfit a house with LED bulbs today could cost around $2,500, according to Bill Watkins, CEO of Bridgelux, at the ribbon-cutting ceremony that took place at the company’s manufacturing facility here. ”It will be down to $200 in three years,” he added.”
Heat is a LED light bulb’s enemy. It converts 20-30% of its power into light but the remainder is converted to heat. This heat is dissipated through a heat sink.
According to the Department of Energy,
“Excess heat directly affects both short-term and long-term LED performance. The shortterm (reversible) effects are color shift and reduced light output while the long-term effect is accelerated lumen depreciation and thus shortened useful life.”
However, not all heat sinks are created equal.
Fact vs Fiction:
In conjunction with this article, I interviewed three lighting experts about how to find the right bulb for commercial and residential applications. Think part two of the LED story. They walked me through on how to decipher the truth from the fiction.
Basically, not all LEDs produce the same type of light, nor last as long. It is best to buy lighting from a store where you can return the lights. Test to see if you like the light output, the color of the light, and whether it dims with your switch. As I mentioned above, I happen to like a white halogen light. Others may not.
Join the Conversation:
- Have you bought any LEDs for your home and if so, which one do you like?
- Would you buy LEDs at this point in time?
- Are you uneasy about the marketing hype about LEDs?
- If you are a lighting expert, which ones do you recommend and why?
About today’s guest blogger: Anna Hackman is a sustainability consultant, mom of four boys (yes, no lamp allowed in the house), and the editor of Green Talk, a green living website that creates the conversation to live a greener lifestyle for home and business. She is passionate about green living, green building, organic gardening, recycling, and green business. Tweet with her @greentalk, yak with her on the GT Facebook fan page, or just visit the blog.