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Get the LED out:A Beginner’s guide to LED lighting Technology March 31, 2009

Posted by Dr. Z Bulbs in How to about lighting, LED Lights, light bulb, Uncategorized.
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Gadzooks! LEDs aren't just for Spaceships anymore..

Zoinks! Its me Dr Z! LEDs are perhaps the newest and least understood lighting technology out there. Here is a great introduction to these enigmatic lights.

Dr. Z



Energy Efficient Homes: Introduction to LED Lighting1

Barbara Haldeman, Wendell A. Porter, Kathleen C. Ruppert2

Quick Facts

  • LED lights are very small, extremely durable, and can be manufactured in a variety of colors and forms.
  • They have the potential to be more energy efficient and last far longer than most current lighting technologies.
  • They are considered environmentally friendly, since they contain no mercury, and the visible light applications for home or business do not emit infrared (IR) or ultraviolet (UV) light.
  • They produce very little heat; and, their lifetime is not affected by frequent on/off switching.
  • The cost of materials needed to make LED lighting has plummeted in the past several years. Although LEDs remain more expensive that their counterparts, their prices are steadily declining.

Terms to Help You Get Started

  • LED Light Emitting Diode
  • SSL Solid State Lighting, a general term for semiconductors that convert electricity into light
  • Semiconductors Solid materials that possess electrical conductivity
  • Diode A simple semiconductor device
  • CFL Compact Fluorescent Lamp (lamp is the lighting industry’s term for bulb)
  • CRI Color Rendering Index, a measure of how a standard series of colors appear under a light source, compared to a reference light source (daylight or incandescent light); CRI is measured on a scale of 0 to 100, with 100 being identical to the reference light source
  • CCT Correlated Color Temperature, a measure of the color appearance of a light source; CCT is measured in degrees Kelvin (K), the absolute temperature scale; white light products commonly range from “warm white” (2700K) to “cool white” (5000K)
  • RGB Red-Green-Blue, the three primary colors of light
  • White light Not an actual “color”, but rather a combination of all wavelengths in the visible spectrum of light

What are LEDs?

Light Emitting Diodes (LEDs) are part of a comparatively new class of lighting called Solid State Lighting (SSL). Unlike incandescent or compact fluorescent lamps (CFLs), LEDs are small electronic components that convert electricity into light.

LEDs are already being used in a variety of applications:

  • Status lights on electronic devices of all kinds
  • Flashlights
  • Decorative lighting strings (both indoor and outdoor)
  • Auto headlamps
  • Traffic lights
  • Outdoor lighting fixtures for parking lots, streets and parks
  • Architectural lighting
  • Retail display lighting
  • Desk and task lights
  • Home lighting applications such as recessed down-lights, and under-cabinet lights

LED applications allow for extraordinary flexibility in lighting design with regard to color, brightness, size, shape, and distribution. There is even a fabric with LEDs incorporated into the weave—imagine t-shirts with designs that change shape and color, or a sofa in an airline terminal with a digital clock displayed across its cushions!

However, in terms of general lighting—that is, general illumination using white light—quality and efficiency can vary greatly from product to product. The U.S. Department of Energy lists several reasons:

  • The technology is new: LED technology is developing fast; new generations of LED devices appear every 4 to 6 months. Last year’s LED light may well be outdated by now, with newer models providing better quality light more efficiently.
  • The technology is different: Because LEDs are completely different from traditional lighting sources, new standards and testing procedures have just been implemented by the ENERGY STAR® program (a collaborative effort of the U.S. Department of Energy and the Environmental Protection Agency) as of June 2008 in the interest of making it easier for consumers to compare products.
  • Everyone’s learning: Because LEDs can be sensitive to some thermal and electrical conditions, manufacturers are racing to develop fixtures or components that are LED compatible in multiple applications.

Ongoing research in LED lighting is happening right now all around the world. Governments and private industry are extremely interested in LEDs both because of their great adaptability in design, and because of the potential energy savings that LED lighting offers. LED lighting will revolutionize home, office, retail, and architectural lighting in the coming years—and that includes general white-light illumination.

How do they work?

LEDs differ from traditional light sources in the way they produce light. In an incandescent lamp, a tungsten filament is heated by electric current until it glows, emitting light. In a fluorescent lamp, an electric current causes the gas inside the tube to emit ultraviolet (UV) radiation, which strikes the phosphor coating on the inside of the glass, causing it to emit visible light.

An LED, on the other hand, is a semiconductor diode, a device that allows current to flow in only one direction. It’s made of a chip of semiconducting material treated to create a structure called a p-n (positive-negative) junction. The positive side contains excess positive charge (“holes,” indicating the absence of electrons) while the negative side contains excess negative charge (electrons).


Figure 1.  PN junction image from NLPIP Lighting Answers, Vol. 7, Issue 3, May 2003 http://www.lrc.rpi.edu/programs/NLPIP/lightingAnswers/led/whatIsAnLED.asp# 

When current is applied, the negatively-charged electrons move toward the positive side, and the positively-charged “holes” move toward the negative side. At the junction, the electrons and holes combine. As this occurs, energy is released in the form of light that is emitted by the LED.

Depending on the alloy used to make the semiconductor, the light emitted by the LED can range through the colors of the rainbow: red, orange, yellow, green, and blue. “White” light is created by combining the light from red, green, and blue (RGB) LEDs, or by coating a blue LED with yellow phosphor.

How does the light produced by LEDs compare to that of incandescents?

White light is a combination of all wavelengths in the visible spectrum. Incandescent lamps inherently produce white light. LEDs do not. They emit light in a very narrow range of the spectrum, producing nearly monochromatic light—the color depending on the materials used to create the LED. “White light LEDs” are created in two different ways: phosphor conversion or RGB. In phosphor conversion, a blue LED is coated with a yellow phosphor, resulting in light which appears white to the eye. This method is lower in cost than the RGB approach. Phosphor converted chips are manufactured in large quantities in forms that are integrated into lighting fixtures.

In the RGB method, white light is produced by mixing the light from multiple red, green, and blue LEDs; sometimes amber is added to enhance the quality of the light. This results in great flexibility in the possible “shades” of white light produced, but is technically more demanding to manufacture, and thus more expensive at this juncture. RGB systems are generally found in custom-designed architectural lighting.

Light quality is indicated by two measurements, correlated color temperature (CCT) and the color rendering index (CRI).

CCT is that aspect of light that people refer to when they talk about “cold” fluorescent lighting; such lighting has a high CCT. CCT is measured in “Kelvins”; cool white light is 5000K while warm white light has a low CCT at about 2700K. Until recently, most white light LEDs had very high CCTs, often above 5000K, but warm white LEDs are now available. They are less efficient than cool white LEDs, but are comparitively efficient as CFLs.

The CRI is a measure of how color appears when illuminated by a light source, compared to reference sources such as incandescent light or daylight. A CRI of 100 is identical to the reference source, so the higher the CRI the better. Everyone has experienced the dull colors and washed-out faces resulting from old-style fluorescent tube lighting, which had a CRI ranging from 50 to 60. Phosphor-converted warm white LEDs are now being produced that are claimed to have a CRI of 80, a value most people find quite acceptable. Others exceeding 90 have also been reported.

The CRI, however, has been found to be inaccurate for white light RGB LEDs and there is controversy in the industry as to the reliability of the rating for other lighting types as well, so a new measurement system is under development.

LED technology is changing quickly; white light LEDs producing high-quality light will be commonplace in the next few years.

Are they energy efficient?

It depends. The best white light LED lamps can meet or exceed the efficiency of compact fluorescent lamps—but many LEDs currently on the market do not. LEDs are sensitive to temperature and electrical conditions, and LED fixtures must be carefully designed to take this into account; many manufacturers are not yet experienced in such design. However, research and development in this area is very active, and new generations of LED devices that are more energy efficient will be appearing on the market within a few years. The U.S. Department of Energy states, “The energy efficiency of LEDs is expected to rival the most efficient white light sources by 2010.”

Are they an economical choice for home lighting?

Currently, good quality LED products are fairly expensive, compared to standard lighting. But costs are coming down—in 2007, they were roughly one-seventh of costs in 2001—and it’s expected that LEDs will be competitive within a few years.

What about ENERGY STAR®?

The ENERGY STAR® Web site states, “Solid-State Lighting (SSL) is the future of lighting, and thanks in part to ENERGY STAR, it’ll be here faster than you think. The ENERGY STAR label on SSL luminaires will provide consumers with the confidence that these products meet efficiency and performance criteria established by DOE in collaboration with industry stakeholders. With test procedures being finalized, the ENERGY STAR SSL program is on schedule to launch September 30, 2008. ENERGY STAR is focusing on lighting applications and products for which the technology has advanced to a point where performance is equal to or better than traditional efficient lighting technologies based on light output, luminaire efficacy and cost. The focus on quality will go a long way to ensure that consumers have a good experience with this new technology.” Visit the ENERGY STAR Web site at http://www.energystar.gov or the Building Technologies Program site at http://www.netl.doe.gov/SSL/energy_star.html for more information.


LEDs for general illumination currently may be considered the “Not Quite Ready for Prime Time” player in the home and office lighting field. But stay tuned—they’re improving quickly. Once industry and ENERGY STAR® standards are fully in place, consumers will be able to comparison shop for LED white lights the way they now do for incandescent and compact fluorescent lights, choosing the lamps and fixtures that give them the combination of light quality and energy efficiency they’re looking for. LEDs are already available for multiple applications in and around the home—from landscape and walkway lighting to holiday lighting, and even ambient lighting in hard to reach places where the long life of LEDs is a real asset—and the future is looking brighter every day.

This document is FCS3280, one of an Energy Efficient Homes series of the Family, Youth and Community Sciences Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. This material was prepared with the support of the Department of Environmental Protection, Florida Energy Office. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the author(s) and do not necessarily reflect the views of the Florida Department of Environmental Protection. Original publication date: June 2008. Visit the EDIS Web Site at http://edis.ifas.ufl.edu.



Barbara Haldeman, editorial assistant, Program for Resource Efficient Communities; Wendell A. Porter, lecturer and P.E., Department of Agricultural and Biological Engineering; and Kathleen C. Ruppert, associate extension scientist, Program for Resource Efficient Communities; University of Florida, Gainesville, FL 32611.



Just for Fun: More info on the Light Bulbs of Ancient Egypt March 24, 2009

Posted by Dr. Z Bulbs in Uncategorized.
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Gadzooks! Due to popular demand I have included another video discussing the possibility of electric light bulbs existing in ancient Egypt. So sit back and enjoy!

Dr. Z


Light Bulb Astrology! or..How Many Leos Does it Take to Change a Light Bulb? March 23, 2009

Posted by Dr. Z Bulbs in Stupid Jokes about Lighting.
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What on Earth is Light Bulb Astrology?

Zoinks!! Its me again! Dr. Z !  Here is a little light bulb astrology to mull over. Thanks to the Milky Way Maid!Enjoy!

Get Lit and Stay Lit

Dr Z



March 19, 2009

by Milky Way Maid

Aries: He’ll jump up to change it right away, but if you don’t have the right size/type bulb, he’ll forget all about it. If you wait a half hour for anything, he’ll forget about it and go on to the next chore.

Taurus: Wait, I’m not ready to change the bulb. I have to move the stack of ironing out of the way and them I’ll go down to the basement and dig out a bulb. Serves me right for buying whatever’s on sale; they never last. OK, now I’ve got it, now where is that Aries?

Gemini: Too busy answering emails and phone messages to actually do it. Is surveying everyone he knows about which brands are best.

Cancer: Loves every task involved in keeping up her beloved home, sweet home. Is only too glad to give her precious home a new light bulb.

Leo: Why don’t we rip out the old fixture and put in makeup lights around the bathroom mirror? How can I possibly look my best if I have to use this 50s-era bathroom to prepare for my entrance??

Virgo: Yes, Virgo has an assortment of new bulbs in organized trays by size and wattage in the basement. Takes 30 seconds to pull out a new one and efficiently replace the old one.

Libra: Honey, can we put in pink lights? They’re so much more flattering. And can I hold the ladder for you, honey? You know I love it when we work on a projects together. What do you think, dear?

Scorpio: Can find his way around in the dark very well. Forget the light bulb. Just take my hand, honey, and trust me.

Sagittarius: Ooh, it’ll be like roughing it. Let’s camp out in the back yard, I can put up a tent in no time. How about it?

Capricorn: Don’t get excited, it’s very simple and routine. Call Virgo to efficiently replace the bulb and bill me.

Aquarius: Better check the continuity on that lamp, it could be the wiring. Better yet, maybe we should rewire the whole house; this is a safety issue!

Pisces: Why does this house hate me? Last month it was the plumbing leak. Next month it’ll probably be the roof flying off. Take me now, Lord.




2007 2008 april aries asteroids astrology astronomy august cancer capricorn christmas december 2007 earth full moon gemini grand trine horoscope jupiter leo libra march mars mars in leo mercury milky way moon nasa New Moon november november 2007 obama october 2007 oort cloud planets saturn scorpio september solar eclipse solar system taurus third week venus virgo weekly weekly horoscope

Dr Z says “Don’t Eat Light Bulbs!” March 23, 2009

Posted by Dr. Z Bulbs in Weird Bulb News.
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Zoinks! Here is a strange little video..of a guy that strangely looks very much like Mr Y eating light bulbs! Please please never eat light bulbs! Gadzooks!

Dr Z



Zoinks some more Energy Saving Light Bulb facts! March 23, 2009

Posted by Dr. Z Bulbs in cfl, compact fluorescent, How to about lighting, light bulb.
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GadZooks! It’s me Dr Z! back from twisting the tungsten and spiralling the bulbs. Light is my life. Below is a great article that lists some more Energy saving light facts! Enjoy!

Dr. Z



Energy saving light bulb facts

As a rule of thumb, a 20-watt energy saving bulb should produce about as much light output as a 100-watt standard bulb – good models produce more.

That means if you replace an ordinary bulb with a quality energy saving bulb, you’ll only use about one-fifth as much electricity – and still have at least as much light as before.

For each ordinary bulb you replace with an energy saving bulb, at current electricity prices it has been estimated you’ll save around $120 over the life of the bulb (8000 hours).

How long do energy saving bulbs last?
An energy saving bulb should last about 5000 to 10,000 hours, whereas an ordinary bulb will generally burn out at around 1000 hours. Used for 3 hours a day, an energy saving bulb should last about 10 years.

Don’t energy saving bulbs produce harsh light?
Not necessarily. Unlike ordinary bulbs, energy saving bulbs come in a range of whites.

If you want lighting that’s similar to an ordinary bulb, say for places where people relax – like lounges – look for “warm white” on the packaging.

In kitchens, bathrooms, laundries and work areas, some people like a ‘cooler bluish-white’ light. If you want this colour, look for “cool white” or “cool daylight” on the packaging.

Don’t energy saving bulbs cost more than ordinary bulbs?
Energy saving bulbs cost more to buy than ordinary bulbs. But a $6 high quality energy saving bulb should last longer than six $1 ordinary bulbs – and you won’t have the hassle of changing bulbs as often.

Buying energy saving bulbs will work out cheaper in the long run. And, energy saving bulbs use 80 percent less power over their life so you’ll save money on electricity use.

From time to time the Electricity Commission subsidises high quality energy saving bulbs. During those times, the subsidised bulbs can be purchased for substantially less than their normal price.

Do they flicker like fluorescent tubes do?
No. Good-quality energy saving bulbs don’t flicker.

Are there any other advantages of energy saving bulbs?
They run cooler than ordinary bulbs, so light fittings don’t get as hot. They are available in a variety of shapes and sizes.


Holy Leprechauns of Light! Images of the Green Team and Top 10 Green Lighting Tips! March 20, 2009

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its not easy being green!

Behold ! Dr Z’s Magical Green Team! Aren’t they cute? Mr Y doesn’t think so.. Bugs Bugs! He hates bugs..These little cuties I found at the end of the rainbow and they know a thing or two about green(enviromentally friendly) lighting. Below is the top 10 green lighting tips. Zoinks!

 Dr Z



Top Green Lighting Tips

  1. CFL: The better bulb
    Compact florescent bulbs (CFLs) are those swirley little guys that look like soft-serve ice cream cones. Actually, they come in a myriad of different shapes, sizes, and colors of light. Economically speaking, they’re a great deal, too. CFLs cost a bit more than an incandescent, but use about a quarter as much energy and last many times longer (usually around 10,000 hours). It is estimated that a CFL pays for its higher price after about 500 hours of use. After that, it’s money in your pocket. Also, because CFLs release less heat, not only are they safer, but your cooling load is less in the summer. CFLs aren’t hard to find anymore, and many cities will give them away for free. Wal-Mart has plans to sell 100 million of them.
  2. Get the LEDs out
    LEDs are a definite TreeHugger favorite. LEDs, or light emitting diodes, are a technology that allows for extremely energy efficient and extremely long-lasting light bulbs. LEDs are just starting to hit the consumer market in a big (read affordable) way and still cost quite a bit more than even CFLs, but use even less energy and last even longer. An LED light bulb can reduce energy consumption by 80-90% and last around 100,000 hours. They even light up faster than regular bulbs (which could save your life it there are LEDs in the brake lights of your car). They are almost always more expensive presently, but we have seen the cost go down steadily. It’s no coincidence that the Millennium Technology Prize went to the inventor of the LED.Most LED lamps on the market have the bulbs built into them, so you buy the whole unit. For screw-in bulbs, check out Ledtronics, Mule, and Enlux. For desk lamps, check out a few affordable ones from Sylvania and Koncept. For more designer models, look at LEDs from Herman Miller and Knoll. Vessel rechargeable accent lamps represent some of the interesting new things LEDs can do as well.
  3. Materials
    Light isn’t all about the bulbs, though. Having eco-friendly lamps and light fixtures is key to greening your lighting. When scouting for new gear, keep your eyes out for lamps made with natural, recycled, or reused materials. Lights made from recycled materials include metal, glass, or plastic, and natural materials can include felt, cloth or wood. Interesting lamps that use reclaimed materials include these made from traffic signal lenses, and these made from wine bottles. Also, don’t be shy about borrowing ideas for reuse in your own projects (see DIY).
  4. Disposabulb
    Fluorescents last a long time, but when they’re dead, they have to be properly disposed of. CFLs, like all florescent bulbs, do contain a small amount of mercury, which means they definitely can’t be thrown in the trash. Every city has different services for recycling, so you’ll need to see what’s offered in your area. LEDs, to our knowledge, do not contain mercury, but the jury may still be out on how to best recycle them.
  5. Wall warts
    Power adaptors, or “wall warts” as they’re affectionately called, are those clunky things you find on many electrical cords, including those attached to lamps and some light fixtures. You’ll notice that they stay warm even when their device is turned off. This is because they in fact draw energy from the wall all the time. One way to green your lighting is to unplug their wall warts when not in use, attached lights to a power strip and turn off the whole switch when not in use, or get your hands on a “smart” power strip that knows when the devise is off.
  6. Daylighting
    By far, the best source of light we know is (yes, you guessed it) the sun, which gives off free, full-spectrum light all day. Make the most of daylight by keeping your blinds open (sounds obvious but you might be surprised). If you want to go a little farther, put in some skylights, or, of you are designing a home or doing a renovation, put as many windows on the south-facing side of the house as possible (or north-facing if you live in the southern hemisphere). To take it even further, sunlight can be “piped” inside via fiber optics and other light channeling technologies. [for more on light piping, check out: 1, 2, 3, 4]
  7. Good habits
    As efficient as your lighting equipment might be, it doesn’t make sense to have lights on when no one’s around. Turn out lights in rooms or parts of the house where no one is. Teach your family and friends about it too and it will become second nature. If you want to get a little more exact, follow these rules:

    Standard incandescent: turn off even if you leave the room for just seconds. Compact fluorescent: turn off if you leave the room for 3 minutes. Standard fluorescent: turn off if you leave the room for 15 minutes.

  8. Do-It-Yourself
    We’re always encouraging people to take matters into their own hands. So much great eco-innovation comes when people create the things they can’t find elsewhere. Lighting is an especially accessible and rewarding thing to tackle. For some inspiration, check out the Cholesterol lamp made from cast-off plastic egg cartons, and the recycled Tube Light. Strawbale building pioneer Glen Hunter made some LED fixtures when he couldn’t find any he liked on the market. Eurolite, the company from which he bought the lighting components, liked his designs so much they decided to sell them.
  9. Dimmers and motion sensors
    Motion sensors can be a good way to keep lights turned off when they’re not needed, and dimmers can give you just the right amount of life, and timers can be set to turn things on and off when needed.
  10. Get green power
    A great way to green your lighting is to buy green power. More and more electric utilities are offering customers a green power option on their bill. Signing up for green power usually means paying a few more dollars a month to support energy in the grid that comes from renewable sources like wind, solar, or biogas. For some more info on how to get green juice, look here, and for the greenest grids in the States, look here. More info is also available in How to Green Your Electricity.


Another LED article this one from Scientific American! March 20, 2009

Posted by Dr. Z Bulbs in Uncategorized.
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Dress for success in an LED dress

LED There Be Light

More energy-efficient light-emitting diodes are rapidly becoming the preferred lighting solution worldwide

By David Biello




FIRST LED CITY: Torraca, Italy, is the first town to be entirely lit by LED lights.

Torraca is a small village of 1,200 people in Italy. It is also the first place in the world to be totally illuminated by light-emitting diodes (LEDs). Representing a sea change, much like when electric lamps first graced London’s Holborn Viaduct back in 1878, some 700 streetlights (each containing 54 LEDS) now line Torraca’s arteries—and locales around the world, from Beijing’s Bird’s Nest Olympic Stadium to the Raleigh Convention Center’s Shimmer Wall in North Carolina, have begun to use LEDs to light up the night.

“There are more than 30 installations like Torraca around the world,” says Mark McClear, director of business development at Durham, N.C.-based LED-maker Cree, Inc., which made the LEDs in Torraca’s streetlamps. “It’s growing weekly.”

The lightbulb of the future may just be a small piece of semiconductor. Rather than heating tungsten to at least 3,100 degrees Fahrenheit  (1,700 degrees Celsius) or exciting fluorescent gases, LEDs can produce lumens with less electricity. Diodes are composed of two conductive materials, such as silicon or germanium; the light-emitting variety uses materials such as gallium arsenide, which releases photons when electricity flows through it.

Such LED technology has been in electronics like calculators for decades, but remains too expensive to replace cheap incandescents. An LED version of a 100-watt incandescent lightbulb, for instance, still costs roughly $80 compared with around $3 for a traditional incandescent.

Cost has been the major obstacle for LEDs, which last up to as 50,000 hours (10 years if used 12 hours a day)—gradually dimming over time—compared with about 800 hours for a typical 100-watt incandescent. “The average bulb is on two hours a day. At that rate, an LED would last 136 years,” McClear says. “If you bought a fixture and only used it two hours a day, it would last longer than your house. It would last longer than you.”

Potential energy savings, however, appear to hold more sway with cities and building owners than cost. After all, some 22 percent of all electricity use in the U.S. is devoted to lighting, according to the U.S. Department of Energy—and switching to LEDs could save $280 billion by 2028. In fact, researchers at the Rensselaer Polytechnic Institute in Troy, N.Y., estimate that replacing incandescents with LEDs could save $1.83 trillion in energy costs globally over the next decade and eliminate the need for 280 1,000-megawatt power plants.

“Forcing electricity though a filament and heating it up to the point where it emits light, [is] horribly inefficient, on the order of 95 percent inefficient,” McClear says. “The best LEDs are on the order of 35 percent more efficient.”

Among those dazzled by LEDs: North Carolina State University in Raleigh, which last year installed 730 Cree LED lights in a dormitory building and saved 44 percent of the energy consumed by the fluorescent predecessors per day, according to the university. Discount chain Wal-Mart has replaced fluorescent light fixtures in its freezer sections with LEDs. And the City of Los Angeles plans to replace some 140,000 street lamps with LED fixtures by 2014 at a cost of $57 million, tapping some of its funding from the Clinton Climate Initiative and the Los Angeles Department of Water & Power.

New LED lights can put out the equivalent light of 100-watt incandescent while only consuming 13 watts of power. They also outlast equivalent compact fluorescent lightbulbs but use 50 percent less energy and skip the toxic mercury required as ballast. The U.S. Environmental Protection Agency (EPA) estimates that 670 million such fluorescent lights end up in the trash yearly and release some two to four tons of mercury per annum into the environment.

Advances in the underlying technology have allowed Cree, for one, to boost output from a single one-square-millimeter diode to 161 lumens per watt. Partially as a result, the Federal Reserve is using LEDs for its overhead recessed lights and the Pentagon has installed some 4,200 LED fixtures to reduce energy costs and improve light quality, according to the U.S. Department of Defense.

Potential downsides: individual LEDs must be kept cool, and it may end up that the tiny fans in the multiple LED fixtures used to cool the lights will wear out long before the diodes. But manufacturers, including Brite Components, Cree, General Electric, Lighting Science Group, Osram and Philips say they are working to offset that problem.

Nevertheless, LEDs will not replace all lightbulbs, because they produce light in only one direction, like a laser, rather than illuminating an area. To fill that lighting need, some companies are creating organic LEDs, or OLEDs, that emit light in all directions and are already used in advanced televisions and other screens.

Such OLEDs—diodes made from organic material such as polyacetylene rather than semiconducting metals—may prove an even more intriguing future solution, because they can be crafted into ceiling panels or even windows (they are often translucent) and are potentially even more efficient at producing light (though not yet). BASF and Osram, for example, have achieved a white OLED capable of 60 lumens per watt. Others have achieved 100 lumens per watt in the laboratory, according to Barry Young, managing director of the OLED Association.

Unfortunately, such an OLED light panel at this point would cost at least $75 per square foot ($800 per square meter) and is not commercially available yet, Young says. But he believes the price tag can be significantly reduced by using plastic polymers and other cheap substances in lieu of glass. OLED lights are likely to become available as soon as 2011, according to a report from display consultants at the firm DisplaySearch in Austin, Tex. “It’s likely to last longer [than LED fixtures] because it doesn’t have anything to fail and it also doesn’t have a lot of heat,” Young says. “It won’t generate the kind of heat that you would in an LED from the standpoint of air-conditioning.”

But even Young believes that LEDs and OLEDs will likely coexist, serving different functions: LEDs will likely replace incandescents whereas OLEDs might light the offices of the future in the form of glowing ceiling panels or windows that light up as the sun sets. “It’s happening faster than anybody thought it would or could,” Cree’s McClear says. “It doesn’t make a lot of sense to do anything that’s not green.”


another LED article! March 16, 2009

Posted by Dr. Z Bulbs in LED Lights.
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LED are great for Hula Hoops.. But are they ready for general lighting?

LEDs are great for Hula Hoops.. But are they ready for general lighting?


Zoinks! Its me Dr Z! Here’s yet another LED article for today. This one is from the New York Times!


Dr Z



March 13, 2009, 5:11 pm
General-Purpose LED Lighting: Not Quite Yet
By Azadeh Ensha

Philips’s E27 LED bulb, part of its Master series. Not quite an all-purpose replacement for the incandescent, but getting closer. Unless incandescent bulbs receive a quick upgrade, federal efficiency mandates will begin making them unwelcome on store shelves beginning in 2012.

Currently, the only viable mass-market alternative is the compact fluorescent light bulb — or C.F.L. — which, despite inarguable energy and cost savings over standard bulbs, have struggled with a variety of consumer concerns.

Meanwhile, makers of light-emitting diode, or LED, technology have so far fallen short of their goal to create another alternative to the incandescent, but that hasn’t stopped them from trying — and they appear to be getting closer.

Royal Philips Electronics, for example, recently introduced its new Master LED lamps to European markets. The electronics maker says the Master LED series combines the benefits of other technologies including incandescent, halogen and C.F.L., without any of their disadvantages.

The Master comes in three flavors — all of them marketed primarily as downlighting or accent lighting for hotels, bars and similar applications. Only the E27 bulb is described as being for “general” use.

The advantages of LEDs over C.F.L.s? Well, they don’t contain mercury or emit harmful ultraviolet rays, for starters. LEDs also turn on instantly, rather than requiring a bit of a ramp-up time to full brightness like compact fluorescents. And unlike C.F.L.’s, an LED’s life span is not shortened by being frequently switched on and off.

The time of the general purpose LED has been long promised. As Claudia H. Deutsch wrote two years ago in The New York Times:

Manufacturers are putting a lot of stock in light-emitting diodes — or LEDs. They operate with chips made of nontoxic materials and last for about 50,000 hours, compared with 1,000 hours for an incandescent and 6,000 for a compact fluorescent. … And, they are extremely energy efficient.

Indeed, for its part, Philips claims that its Master LED lamps can last up to 45,000 hours and provide up to 80 percent energy savings compared with standard low-wattage halogen and incandescent spot lamps. So what’s still holding the LED bulb back?

For one thing, there is the cost. Nowadays, a consumer can pick up a C.F.L. for as little as $2. The Philips Master LED is priced significantly higher. A quick search placed it at 30 euros or around $40 on this Web site — though over its lifetime, that could represent significant savings over other bulbs.

The character of the light is also an issue. At the moment, LEDs are better suited for spot and directional lighting, rather than the general-area lighting associated with, say, an incandescent floor lamp. And even innovative LED bulbs like the Master are only designed to replace up to a 40 watt incandescent bulb — or at least that’s roughly the amount of light a consumer might expect to get out of one.

Considering that a general purpose home lamp typically uses 60, 75 or 100 watts, that’s not very powerful.

Still, it’s not entirely fair to compare LEDs and C.F.L.’s — at least not yet. And as Nadarajah Narendran, the director of research at the Lighting Research Center in Troy, N.Y., puts it: “There are technical differences between C.F.L.’s and LEDs, but ultimately it comes down to the manufacturing process and the quality of the finished product. Even within the same technology, all products are not created equal.”

LED article. Are we going to get the lead out on using LEDS? March 16, 2009

Posted by Dr. Z Bulbs in List Article, Theory for argument sake..
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Zoinks! LED are the illumination device to be getting lots of press in the last year? Could they be the future of lighting? I don’t know… I still haven’t seen anything that has knocked my socks off (more on that later)but they would look good on the Starship Enterprise! The article below is a great introduction to some of the more positive views on LED technology!Dr Z


Future bright for LED lights in homes

Panasonic Electric Works Co.’s LED lighting equipment is displayed at the company’s new products showroom in Koto Ward, Tokyo.

Light-emitting diodes (LEDs) that can be used as home lighting are becoming more common, but the cheaper-to-use and environmentally friendly devices are still relatively expensive to install.

Electric device makers are expanding their LED product lineups as production costs edge down, and are expected to become the principle lighting devices of the future.

LEDs are semiconductors that emit light when a current passes through them. The electric appliance industry has nicknamed LED technology as the fourth light, after candles, lightbulbs and fluorescent lamps.

LED lights are smaller, lighter, more durable and consume less electricity than conventional lighting products. They already are used in traffic signals, as back lights for cell phones and in other products. But it is only recently that LEDs have made the leap to household lighting equipment.

Toshiba Lighting & Technology Corp. is scheduled to release Wednesday LED lightbulbs that can be used with conventional lightbulb bayonet mounts. The products have the same level of brightness as a 40-watt lightbulb.

Though priced at 10,500 yen, including consumption tax, it is said to have a 40,000-hour life span. This makes the devices 40 times more durable than conventional light bulbs and about seven times that of the company’s fluorescent lamps. If an LED light was used for 10 hours every day, it would last more than 10 years. Because LEDs also use much less electricity than a lightbulb, using one for 40,000 hours–about 10 years of normal use–means electric bills would be about 20,000 yen lower than using an ordinary lightbulb for the same length of time.

Panasonic Electric Works Co. plans to increase its home-use LED lineup from 80 products to 210 starting next month. Its LED downlight priced at 25,620 yen has the same level of brightness as a 60-watt light bulb. The products’ life span also is 40,000 hours and is said to be able to cut annual utility fees by about 85 percent.

The biggest hurdle for LED lighting is the high price, but production costs are steadily declining.

Kuniaki Matsukage, Panasonic Electric Works’ director of lighting equipment, said, “Around 2012, I predict that prices of our LED products will be halved, and I believe they’ll be the most common form of lighting equipment.”

(Mar. 16, 2009)

Holy Leprechauns of Light! A New Dr Z Video! March 13, 2009

Posted by Dr. Z Bulbs in light bulb, Weird Bulb News.
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Dr Z

Holy leprechauns of light! Its me Dr. Z ! I have a new video in which I introduce my “green” team in honor of saving the enviroment, St Patrick’s Day, and drinking green Guinness beer. Light bulbs and madness take place. Compact fluorescent zbulbs! Leprechauns! Mr Y stole my Shamrock shake!