LED there be light

Jun 22, 2009 By Marsha Walton

Q: How many LED engineers does it take to change a light bulb?

A: Why on Earth would you ever need to change a light bulb?

While (light-emitting diode) costs are still high, this type of lighting is extremely long-lasting. And as prices come down, its efficiency could lead to huge energy savings.

The first consumer LED products lit up in the 1970s, with red light numbers on pocket calculators and push-button displays on big, geeky Pulsar watches. Then came those centered, high-mounted brake lights in the rear windows of cars. Now LEDs are found in everything from traffic lights to operating rooms to greenhouses.

An LED is a device that produces light when an electrical current flows through it. The color it emits depends on the materials used to make the diode.

"It won't be long before LED lighting technology has a space on your desk, has a space on your ceiling, certainly has a space on your car," says Russell Dupuis, an electro-optics professor at the Georgia Institute of Technology. Dupuis was awarded the 2002 National Medal of Technology for his work on LEDs.

"Most cars today have a whole lot of LED, certainly the instrument cluster," he says.

And some cities are also investing in LED for their roads. Dupuis says LED traffic signals would pay for themselves in about three months because of energy savings. And how long do they last? "Until somebody knocks the pole down!" he laughs.

Here are some numbers from the U.S. Department of Energy comparing lifetimes of LEDs to traditional lighting:

• Incandescent bulbs (750-2,000 hours): These bulbs haven't changed much in 120-plus years; they give off 80-percent heat and only 20-percent light.

• Compact fluorescent bulbs (8,000-10,000 hours): CFLs are more efficient than incandescent, but do contain small amounts of mercury.

• High-power white LEDs (35,000-50,000 hours): The Department of Energy estimates a quarter of the electricity in the United States is used for lighting, costing $50 billion per year. The agency says new technology could reduce lighting energy use by 50 percent.

For some big companies, the transition already makes sense. "Walmart decided to replace the lighting in all of its refrigerated cases with LED lights," Dupuis says. "Every store is going to save enough in six months to pay for this change."

There's also a niche for special lighting needs. Some surgical teams are using LED headlamps and operating-room lighting. LEDs also light up the words of the Constitution and Declaration of Independence at the Jefferson Memorial. And at the British Museum they illuminate the Beatles' "Sergeant Pepper's Lonely Hearts Club Band" uniforms so the fabric doesn't decay.

OLEDs, or organic light-emitting diodes, have other intriguing potential. They can be created on paper-thin plastics, and made into wallpaper, window blinds, even clothing.

But it will be several years before consumers can pick up a pack of LEDs at the hardware store. "Designing lights with LED has inherent challenges," says Michelle Murray, a spokeswoman for LED lighting manufacturer Cree Inc.

Those challenges prompted the Department of Energy to launch the L-Prize, a competition offering millions in cash prizes for the creation of a "high-quality, high-efficiency solid-state lighting products to replace the common bulb."

The Department of Energy admits major consumer confusion when it first started promoting the efficiency of compact fluorescent lights. It says the United States cannot afford to squander the enormous energy-saving potential of LEDs, so it wants to make sure the products are ready for prime time when they do hit the market.

The Department of is setting 2012 as a target for large-volume production and replacement of incandescent lighting.

___

(c) 2009, Mother Nature Network.
Visit the Mother Nature Network on the World Wide Web at www.mnn.com.
Distributed by McClatchy-Tribune Information Services.

Explore further: Cadillac CT6 will get streaming video mirror

add to favorites email to friend print save as pdf

Related Stories

Powerful Little Light: LED With 1,000 Lumens

Mar 15, 2007

Osram has developed a small light-emitting diode spotlight that achieves an output of more than 1,000 lumens for the first time. That’s brighter than a 50-watt halogen lamp, thereby making the device suitable ...

The Green (and blue, red, and white) lights of the future

Dec 17, 2008

A revolution in energy-efficient, environmentally-sound, and powerfully-flexible lighting is coming to businesses and homes, according to a paper in latest special energy issue of Optics Express, the Optical Society's open-a ...

Standards Set for Energy-Conserving LED Lighting

Jun 26, 2008

Scientists at the National Institute of Standards and Technology (NIST), in cooperation with national standards organizations, have taken the lead in developing the first two standards for solid-state lighting ...

High-brightness breakthrough

Jun 28, 2005

As a result of cooperation between Philips Lighting, Philips Research and Novaled have announced a new record for the efficiency of high-brightness white OLEDs, a new solid state lighting technology. OLEDs are expected to ...

Recommended for you

Cadillac CT6 will get streaming video mirror

5 hours ago

Cadillac said Thursday it will add high resolution streaming video to the function of a rearview mirror, so that the driver's vision and safety can be enhanced. The technology will debut on the 2016 Cadillac ...

Poll: Americans skeptical of commercial drones (Update)

Dec 19, 2014

Americans broadly back tight regulations on commercial drone operators, according to a new Associated Press-GfK poll, as concerns about privacy and safety override the potential benefits of the heralded drone ...

Cheaper, more powerful VR system for engineers

Dec 17, 2014

It's like a scene from a gamer's wildest dreams: 12 high-definition, 55-inch 3D televisions all connected to a computer capable of supporting high-end, graphics-intensive gaming.

Nokia HERE prepares maps for autonomous cars

Dec 17, 2014

Autonomous cars will need a new kind of map, a crucial element that until now has been given a back seat to the more popularly discussed issues of sensors and legal questions. Senior Writer Greg Miller in ...

Dutch launch 'intelligent bicycle' that warns of danger

Dec 15, 2014

The Netherlands on Monday launched its first-ever "intelligent bicycle", fitted with an array of electronic devices to help bring down the high accident rate among elderly cyclists in the bicycle-mad country.

User comments : 3

Adjust slider to filter visible comments by rank

Display comments: newest first

DGBEACH
5 / 5 (1) Jun 23, 2009
"Designing lights with LED has inherent challenges," says Michelle Murray, a spokeswoman for LED lighting manufacturer Cree Inc.

Heat dissipation and color matching are both quite manageable issues to deal with by any competent engineer. The real hurdle to full implementation is the cost of the LEDs themselves, which companies like Cree has opted to maintain at higher levels in order to quickly recoup their R&D exposure, when they should actually be leading by example to spur on early adopters.
I am a real proponent of LED lighting, and see a future lit-up mainly with LEDs...but I now think that they will be lighting my children's living rooms (5-10 yrs from now)...2012 is an overly ambitious target IMHO.
Nik_2213
5 / 5 (1) Jun 23, 2009
Uh, we've a light fitting that used to have 3 @ 100 Watt incandescent tungstens.

Then it had one 40 Watt tungsten and two 18 Watt CFLs. Why ? Simple, the CFLs start slowly and *flicker*. This could be fatal given a family member with photo-sensitive epilepsy, and lights mounted over the stairs. One fast-starting tungsten will mask the flicker...

Anyway, I coughed up £ 10 ($15) for an LED bulb. It was brilliant --pun intended-- but lasted barely a month. That's the problem with early uptakers, they hit rim of the infamous 'bathtub curve'...
DGBEACH
5 / 5 (1) Jun 23, 2009
Uh, we've a light fitting that used to have 3 @ 100 Watt incandescent tungstens.



Then it had one 40 Watt tungsten and two 18 Watt CFLs. Why ? Simple, the CFLs start slowly and *flicker*. This could be fatal given a family member with photo-sensitive epilepsy, and lights mounted over the stairs. One fast-starting tungsten will mask the flicker...



Anyway, I coughed up %uFFFD 10 ($15) for an LED bulb. It was brilliant --pun intended-- but lasted barely a month. That's the problem with early uptakers, they hit rim of the infamous 'bathtub curve'...


It's too bad that your first experience was a bad one, and unfortunately this will occur over and over again until one of the "Big Guys" (ie.GE, Siemens, and Phillips) get into the domestic lighting race in a big way. Those little Chinese mom-and-pops don't design their products to last, they lack the skill and knowledge required to pull even something as simple as an LED lamp off.
A European or North American (trained) designer would allow for ample heat dissipation, and tight current control, which are the two most important design criteria to be tackled in LED lighting.
But like I last said, they (LED lights) WILL be our lighting in the future...think of your £10 as an investment in our futures...thanks mate! :)

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.