Cheaper Color-Changing Window

Stained glass: These photos show the two electrodes that make up the color-changing part of an electrochromic window. The clear electrode on the left has has been impregnated with lithium. The dark electrode on the right been drained of ions.   Credit: NREL

Thin, battery-like films change color when the weather changes.

By Katherine Bourzac

Thirty percent of the energy used by buildings in the United States is spent making up for heat loss or gain through windows. That adds up to about $40 billion in electricity costs each year. Windows that change color in response to changes in the weather can help save on electricity costs by absorbing sunlight in the winter and reflecting it in the summer. Such windows have existed for awhile, but they are expensive and not widely used. Now researchers are developing cheap printing methods for making these electrochromic systems, and hope to make electrochromic films that can be cut to fit existing windows.

Electrochromic windows sandwich materials that change color when a small electrical field is applied across them. This change is triggered by changes in light or temperature measured by sensors. “With electrochromic windows, everything happens dynamically–you don’t have to think about it,” says Anne Dillon, senior scientist at the National Renewable Energy Laboratory (NREL). “The problem is, they’re too expensive.”

This week at the Materials Research Society meeting in Boston, Dillon and research scientist Robert Tenent at NREL presented their new and potentially cheaper method for making electrochromic windows.

Typical electrochromic systems are made up of two electrodes separated by an electrolyte that shuttles ions between them. The electrode materials, usually oxidized metals, change color when an ion such as lithium moves into and out of them.

The NREL systems are based on electrodes made of nickel oxide and tungsten oxide and are the first electrochromic systems to be made by spraying down cheap precursors and then heating them. NREL has tested the systems using a liquid electrolyte, and is currently developing systems that rely on solid ion conductors. When a voltage is applied across the NREL system, lithium ions move out of the nickel oxide and into the electrolyte; on the other side, lithium ions move into the tungsten oxide. The movement of the ions causes the two electrodes to color.

Spraying the films is not only a cheaper alternative, says Tenent, it also provides some advantages in performance. The NREL team found that adding a small amount of lithium to the nickel-oxide ink solution before it’s printed made for a film that changes color much faster and within a wider range. In 29 seconds, as lithium leaves the nickel electrode and it darkens in color, the electrode goes from transmitting 80 percent of incident light to transmitting just 30 percent. Adding a small amount of lithium using conventional manufacturing techniques would be much more difficult, Tenent says.

There are other ways to make color-changing windows–by using materials that undergo a chemical change in response to light, for example. But these materials are prone to degradation. The NREL group is developing the metal-oxide electrodes in the hopes that these materials, which are robust and don’t degrade in response to light, will have long lifetimes.

So far, the NREL system has been tested on glass substrates. To make a truly affordable window coating, the group is working to make electrochromic films based on flexible, transparent plastics. The group is talking to DuPont, which makes plastics, about collaborating to fabricate electrochromic films sandwiched between one of the company’s heat-tolerant polymers. The nickel-oxide precursor must be heated to about 300 ºC in order to form the electrode material, a temperature many plastics can’t tolerate.

http://www.technologyreview.com/energy/24049/

Carbon Fiber Ribbon of Light

I would have assumed this lamp was aluminum, had designer Marcus Tremonto not explained:

“The complexity of curves and required thinness could not be duplicated in any other material while still maintaining its ability to support itself completely…”

Usually when I picture carbon fiber, I imagine that monotonous, slate-colored slab that’s delicately thin but mostly flat—or I picture the Ossur cheetah legs that are curved but only for industrial utility.

I’d never imagined carbon fiber as a ribbon of light.

[Contemporist via cribcandy]

Send an email to Mark Wilson, the author of this post, at mark@gizmodo.com.

http://gizmodo.com/5402189/carbon-fiber-ribbon-of-light

OLED technology explained using a pickle and an Igor

Say bub, do you care to know what all that OLED jazz is about? We’ll bet you do, but you don’t wanna read some dry polysyllabic academic paper written by five guys during their time away from the lab. What you want is a sharp demonstration, preferably by an MIT professor, that goes straight to the point of what an Organic Light Emitting Diode is. Igor, roll in the pickle, please. Okay, he’s not an Igor, his name is Vladimir Bulovic, but he does a terrific job of explaining how the passing of electric current excites organic molecules into creating those luscious ultra-bright colors we lust after that can fit inside ridiculously small spaces. Slide past the break to see the vid in full, and yes, it’s just as weird as you think it’ll be.

[Via OLED Display] – Follow the link to see the video

http://www.engadget.com/2009/10/02/video-oled-technology-explained-using-a-pickle-and-an-igor/

Six-watt dimmable LED bulb comes to U.S.

Is it time to make the leap to LED lights for the home? Perhaps, but only if you’re willing to make a return-on-investment calculation.

Lemnis Lighting on Friday said that its Pharox60 LED light is now available in the U.S. online and soon will be for sale on Amazon. The dimmable bulb, shaped like a traditional incandescent bulb, consumes 6 watts of power and can replace a 60-watt bulb.

That dramatic drop in electricity use comes at the cost of $39.95. The premium can be recouped in three years, or as little as one year for consumers with time-of-day pricing tariffs, according to the company. The current price is a special offer; the bulb will cost $49.95 after the beginning of next year.

“Compared to the entry price for solar panels, we feel this is a more accessible energy saving investment,” said Warner Philips, founder of the Netherlands-based company whose great-grandfather founded the Dutch lighting giant Philips.

The LED bulbs are estimated to last 25 years, significantly longer than compact fluorescent bulbs, which use more electricity for similar level of lighting output, or lumens. The Pharox60 bulb can be recycled with metal and glass materials, according to the company.

LED backers have long advocated solid-state lighting because it consumes one-tenth the power of incandescent bulbs and lasts longer. But the high price tag has meant that LEDs are mainly used for commercial applications.

Because there is concern that manufacturers will overstate the efficiency benefits or light output, the Department of Energy has set up a “Lighting Facts” Web site and label to guide consumers. Lighting Facts lists the Pharox bulb bulb among those that perform as claimed.

http://news.cnet.com/8301-11128_3-10366221-54.html?tag=newsEditorsPicksArea.0

Build a better bulb: $10 million prize

Credit: Philips/Department of Energy.  Here is Philips’ entry.

The ubiquitous but highly inefficient 60-watt light bulb badly needs a makeover. And it could be worth millions in government prize money–and more in government contracts–to the first company that figures out how to do it.

Right now, that company could be Philips, the Dutch electronics giant. The company announced Thursday that it had submitted the first entry for the L Prize, an Energy Department contest that will award up to $10 million to the first person or group to create a new energy-sipping version of the most popular type of light bulb used in America.

As the first entrant, Philips will win the prize if its claims hold up. Testing of the Philips lamp will take close to a year to complete as the department independently evaluates the company’s claims.

“Philips is confident that the product submitted meets or exceeds all of the criteria for the L Prize,” Rudy Provoost, chief of Philips Lighting, said in a statement.

The $10 million is almost beside the point. More important, the contest winner will receive consideration for potentially lucrative federal purchasing agreements, not to mention a head start at cracking a vast consumer marketplace.

The L Prize has garnered significant attention in the lighting industry because 60-watt incandescent lamps represent 50 percent of all the lighting in the United States, with 425 million sold each year. The Energy Department says that if all those lamps were LED equivalents, enough power would be saved to light 17.4 million American households and cut carbon emissions by 5.6 million metric tons annually.

For decades, incandescent light bulbs continued to bear a strong resemblance to Thomas Edison’s creations, but new energy standards that go into effect in 2012–and would effectively outlaw today’s incandescent bulb–have brought about a period of fertile innovation in the lighting industry.

One of the first attempts at greater efficiency was the now-maligned compact fluorescent bulb, but there have also been efforts to modify incandescent technology to conform to the new standard. LED bulbs are now available in stores, but those models have limited output and high prices. A faithful reproduction of an incandescent bulb’s light from an inexpensive and efficient source has been the industry’s ultimate goal.

Philips has delivered 2,000 prototypes of its bulb to the Energy Department for testing. The company says the bulbs meet all the criteria of the contest, which specifies a bulb that reproduces the same amount and color of light made by a 60-watt incandescent bulb, but uses only 10 watts of power. The bulb must also last for more than 25,000 hours–about 25 times longer than a standard light bulb. In a nod to economic concerns, at least 75 percent of the bulb must be made or assembled in the United States.

If the new bulb passes the department’s testing regimen, it will be an even more efficient, longer-lasting lighting device than today’s compact fluorescent bulbs. The department considers the introduction of compact fluorescents, today’s alternative to standard bulbs, to have been a debacle.

At first, the department set no standards for compact fluorescent bulbs and inferior products flooded the market. Consumers rebelled against the bulbs’ shortcomings: the light output from compact fluorescent bulbs was cold and unpleasant, their life is much shorter than claimed, many were large and undimmable, they do not work in cold environments and they contain toxic mercury.

By setting rigorous criteria for the L Prize, the department hopes LED bulbs can avoid a similar fate. That also means rejecting current LED bulbs that can claim some technical similarities, but fall far short of the L Prize’s goals.

“We’ve probably eliminated almost 25 products that were horrible,” said James R. Brodrick, manager of the Solid State Lighting Program of the Energy Department. “We test LED bulbs today that claim on the package that they’re equivalent to 40 watts, but are really like 20-watt bulbs.”

“This will be the most publicly tested bulb ever,” Brodrick said.

The Philips LED lamp represents a “significant energy savings,” said Nadarajah Narendran, the director of research at the Lighting Research Center at Rensselaer Polytechnic Institute. “This has now leapfrogged what CFLs can do.”

The Energy Department will also award $5 million to the creator of an LED reflector lamp (no entries have yet been made) and a new, “21st-century lamp,” the specifications of which are yet to be defined.

General Electric–along with Philips and Osram Sylvania, one of the world’s biggest lighting suppliers–said that it would introduce a new LED module next month that would make it easier to replace traditional light sources with LEDs. Osram had no comment about its plans.

The first certified products, due in about a year, will not be cheap. Today’s LED-based bulbs cost up to $100 each, and while there is plenty of optimistic talk about reducing that price, a clear path to affordability remains elusive.

To lower the cost, Brodrick has enlisted 27 utility companies around the country as L Prize partners, with the hope that utility subsidies, along with mass production, will help cut the cost. One such utility, Southern California Edison, will both test the bulbs and offer rebates to consumers, according to Gregg Ander, the company’s chief architect.

“There’s a potential for LED lamps to be much more acceptable to the consumer than compact fluorescents,” Ander said. He said he expected that eventually, an LED substitute for a 60-watt bulb would cost the same as its compact fluorescent equivalent, factoring in its longer life.

Kevin Dowling, vice president for innovation at Philips Solid State Lighting Solutions, is confident that the LED light bulb can become an affordable option. “Over the long term, we can absolutely get the cost down to the $20 to $25 range,” he said.

Entire contents, Copyright © 2009 The New York Times. All rights reserved.

http://news.cnet.com/Build-a-better-bulb-10-million-prize/2100-11392_3-6250105.html?tag=newsEditorsPicksArea.0

Are ESL bulbs better than CFL or LED?

Vu1’s conceptual design for its R-30 bulb.  (Credit: Vu1)

A novel design for energy-efficient light bulbs can produce incandescent-quality light and does not contain mercury like compact fluorescents (CFL), according to manufacturer Vu1.

The Seattle-based firm has been working on an alternative to CFLs and LED lights for five years and just rolled out a demo video, below.

Vu1’s Electron Stimulated Luminescence (ESL) lights can last up to 6,000 hours, about three to four times the lifespan of incandescents and comparable to CFLs. They produce 50 percent less heat than incandescents.

The ESL bulbs contain an electron source that fires electrons at a proprietary luminescent phosphor, which then glows. The screw-in apparatus is encased in standard light bulb glass.

One disadvantage to CFLs is they contain about 5 milligrams of mercury, a small amount but enough to prompt some jurisdictions to ban dumping them in the trash. Burnt-out CFL bulbs should be disposed of with hazardous waste where possible or returned to the retailer, which then recycles them. The EPA recommends evacuating the room if a CFL bulb breaks.

ESL bulbs will be trash-bin disposable, according to Vu1.

Meanwhile, LED bulbs are energy efficient at around 40,000 to 50,000 hours a bulb but tend to be expensive. For instance, Panasonic’s new Everleds light will likely retail for around $40 when it hits stores in Japan next month.

Vu1’s ESL bulb would be around $20 when it hits the market, according to spokesman James Quick. Vu1 might market the bulb in mid-2010 if its funding holds up. It plans to begin manufacturing at its EU plant by the end of this year.

The company says its ESL bulbs would produce light that’s “essentially indistinguishable” from incandescents, contrasting it with the greenish or bluish light from CFLs and LEDs. To my eye, the ESL light in the video looks a shade colder than incandescent.

The prototype ESL R-30 bulb, which would replace a 65-watt incandescent bulb, has a color rendering index of more than 90 and a color temperature of 2800K, according to Vu1. It also turns on instantly and is fully dimmable.

ESL looks quite promising. Let’s see if this bright idea makes it to market.

(click the link to see a video clip ) – http://news.cnet.com/8301-17938_105-10354160-1.html?tag=newsEditorsPicksArea.0

Ultrathin LEDs Create New Classes Of Lighting And Display Systems

Stretchable micro-LED display, consisting of an interconnected mesh of printed micro LEDs bonded to a rubber substrate. (Credit: Photo by D. Stevenson and C. Conway, Beckman Institute, University of Illinois)

A new process for creating ultrathin, ultrasmall inorganic light-emitting diodes (LEDs) and assembling them into large arrays offers new classes of lighting and display systems with interesting properties, such as see-through construction and mechanical flexibility, that would be impossible to achieve with existing technologies.

Applications for the arrays, which can be printed onto flat or flexible substrates ranging from glass to plastic and rubber, include general illumination, high-resolution home theater displays, wearable health monitors, and biomedical imaging devices.

“Our goal is to marry some of the advantages of inorganic LED technology with the scalability, ease of processing and resolution of organic LEDs,” said John Rogers, the

Flory-Founder Chair Professor of Materials Science and Engineering at the University of Illinois.

Rogers and collaborators at the U. of I., Northwestern University, the Institute of High Performance Computing in Singapore, and Tsinghua University in Beijing describe their work in the Aug. 21 issue of the journal Science.

Compared to organic LEDs, inorganic LEDs are brighter, more robust and longer-lived. Organic LEDs, however, are attractive because they can be formed on flexible substrates, in dense, interconnected arrays. The researchers’ new technology combines features of both.

“By printing large arrays of ultrathin, ultrasmall inorganic LEDs and interconnecting them using thin-film processing, we can create general lighting and high-resolution display systems that otherwise could not be built with the conventional ways that inorganic LEDs are made, manipulated and assembled,” Rogers said.

http://www.sciencedaily.com/releases/2009/08/090820161129.htm

SunFlower LEEDS

[All photographs by David Newsom.]

These awesome, 12-foot-tall, sunflower-inspired solar panels are part of a permanent (and functional) art installation in Texas. When the Mueller Development, a 10,000-soul New Urbanism community in Austin, signed off on the development of a large retail lot within their confines, part of the agreement was that the developers pay for something to draw the eye away from the less-than-attractive strip of loading docks behind the store.

Massachusetts-based art duo Mags Harries and Lajos Heder were commissioned to design an installation, and the result was SunFlowers, a series of fifteen solar towers that look like flowers. They soak up enough sun during the day to power the on-board LEDs at night, and excess juice goes back into the grid. Everyone wins, including the environment. Suh-weet!

via good magazine

http://www.core77.com/blog/object_culture/sunflower_leeds_14354.asp

Making Light Bulbs from DNA

Dye-doped DNA nanofibers can be tuned to emit different colors of light

By adding fluorescent dyes to DNA and then spinning the DNA strands into nanofibers, researchers at the University of Connecticut have made a new material that emits bright white light. The material absorbs energy from ultraviolet light and gives off different colors of light–from blue to orange to white–depending on the proportions of dye it contains.

The researchers, led by chemistry professor Gregory Sotzing, create white-light-emitting devices by coating ultraviolet (UV) light-emitting diodes (LEDs) with the material. They are even able to fine-tune the white color tone to make it warm or cold, as they report in a paper published online in the journal Angewandte Chemie.

The new material could be used to make a novel type of organic light bulb. The light emitters should also be longer-lasting because DNA is a very strong polymer, Sotzing says. “It’s well beyond other polymers [in strength],” he notes, adding that it lasts 50 times longer than acrylic.

The color-tunable DNA material relies on an energy-transfer mechanism between two different fluorescent dyes. The key is to keep the dye molecules separated at a distance of 2 to 10 nanometers from each other. When UV light is shined on the material, one dye absorbs the energy and produces blue light. If the other dye molecule is at the right distance, it will absorb part of that blue-light energy and emit orange light.

http://www.technologyreview.com/energy/23042/

Eternaleds debuts world’s first liquid-cooled LED light bulb

We know you probably wouldn’t answer “What’s the perfect companion to a liquid-cooled PC?” with “a liquid-cooled light bulb,” but amazingly enough, that’s a viable answer starting today. Eternaleds is stepping up big with planet’s first liquid-cooled LED bulb, the HydraLux-4, which will arrive in warm white and daylight white and should save you bundles on your energy bill over the next score. The company asserts that these bulbs produce “360 degree lighting” and can emit the same amount of illumination as a 25W incandescent with just 4W of energy. Each bulb is rated for 35,000 hours of use, and considering that a single one costs only $1.75 per year to run (at eight hours per day), we suppose the stiff $34.99 sticker is somewhat warranted.

http://www.engadget.com/2009/07/15/eternaleds-debuts-worlds-first-liquid-cooled-led-light-bulb/