This article was taken from the October 2011 issue of Wired magazine. Be the first to read Wired's articles in print before they're posted online, and get your hands on loads of additional content by subscribing online.
Brett Sharenow is presiding over the Pepsi Challenge of lightbulbs. The CFO of Switch, a Silicon Valley startup, Sharenow has set himself up in a small booth at the back of the Pennsylvania Convention Center in Philadelphia, and he's asking passers-by to check out two identical white shades.
Behind one hides a standard incandescent bulb, the familiar lighting technology that has gone largely unchanged since Thomas Edison invented it 132 years ago. Behind the other is a stunning, almost Art Deco-style prototype that holds ten LEDs and a secret fluid. It's a liquid-cooled bulb, as radically different from Edison's invention as anything that's ever been screwed into a standard socket and, Sharenow hopes, the next big thing in the £18 billion lighting industry. The challenge: can you tell which is which?
It's day one of Lightfair, the annual international trade show for everything that glows, glares, flickers or shines -- 500 exhibitors and 24,000 visitors prowling row after row of light after light. This is the last Lightfair before new regulations governing light-bulb efficiency begin to take effect in the US in January, and there's a real sense of history and urgency on the show floor. Ready or not, the way that Americans -- and EU citizens -- light homes and offices is about to change, and the technology that will lead the way is somewhere in this hall. In the US, the provisions of 2007's Energy Independence and Security Act will effectively ban all incandescent bulbs by 2014. In the European Union, all incandescents will be banned for use in the home by 2012. They will mostly be replaced throughout the 27-state bloc with "compact fluorescent light" (CFL) bulbs, which have attracted much criticism, not least for their mercury content. So the race to find a better replacement for fluorescents is still very much alive. The industry is banking on LED lighting, and it's virtually the only bulb technology on display at Lightfair: there's barely a single incandescent or sickly CFL to be seen. Just 6,000m2 of companies racing to fill the world's billions of standard sockets -- and betting on LEDs as the way to do it.
There's an excellent reason why LEDs have taken on the aura of inevitability: they are semiconductors, and like all solid-state technology they are getting better and cheaper on a predictable curve. In 1999, a researcher named Roland Haitz, then head of semiconductor R&D at Hewlett-Packard, coauthoured a paper that became known as "Haitz's Law", the lighting industry's manifesto. By charting the historical prices of LEDs and projecting forward, Haitz estimated that the amount of light that they produced would increase by a factor of 20 per decade, while the cost would drop by a factor of ten. Haitz's Law has proven remarkably accurate. But the lighting industry still has major hurdles to clear before LEDs gain acceptance from consumers.
Beyond the very real technical issues -- cooling, costs, light colour -- there's the public's lingering distaste for CFLs, which in the US failed miserably in their projected role as the bulb of the future. That sentiment has fed into a Tea Party-fuelled backlash against the regulations -- with attempts to roll them back entirely.
Incandescents convert less than ten percent of the energy pumped into them into light, losing the rest as heat. More efficient bulbs could save billions of pounds, decrease dependence on foreign oil, and significantly reduce greenhouse gases. Still, the consumer backlash resonates and not simply because CFLs are horrible, flickery, ugly and unreliable. Evolutionary biologists believe that human lighting preferences are the result of our trichromatic vision (possessing three independent channels for conveying colour information) -- rare in non-primates -- which makes us particularly suited to daylight and the perception of primary colours. There's an anthropological component as well: for 400,000 years, humankind has been banishing darkness with fire. And Edison's bulb is, at its core, a burning filament.
Abandoning incandescents means abandoning fire as a light source for the first time in our history.
The front of the hall at Lightfair is the province of the industry's big three -- Philips, Osram Sylvania and General Electric (GE), founded by Edison. The behemoths give way to a second tier occupied by the likes of Toshiba, Samsung, Leviton and Honeywell. Behind them, smaller companies -- accessory makers, vendors and Asian component suppliers -- fill out the rest of the available floor space, right up to the back wall. Here, Sharenow is presiding over the Switch booth. "Which one is which?" Sharenow asks. Most people get it wrong, which is significant. When they select what they feel is the superior light, they're selecting the Switch. Though there are countless 60W LED prototypes in evidence, few are available for side-by-side comparisons with incandescents. Most are sealed inside display cases. The Switch bulbs are out in the open: crystalline shells of clear, faceted glass, with aluminium prongs holding yellow-tinted LEDs that shine through the cooling liquid to cast a warm, living-room-quality glow -- and draw only 13 watts to do it.
Most lightbulbs are rated at or equivalent to 60W or 100W, but nearly every LED brought to market so far has come in the 40W equivalency range, good for little beyond cupboards. Brighter bulbs are either too hot, too expensive (upwards of £30, though they can last for 20 years) or both. Switch plans to start selling its 60W-equivalent bulb this autumn for around £18. "People have always needed light," Sharenow says. "This is a light source people will want."
Though fluorescent lighting has been around since the 30s, GE physicist Ed Hammer was the first, in 1975, to figure out how to twirl that long gas-filled tube so it would screw into a standard socket. (His twisty tube was a major achievement, so tricky to produce that many CFLs are still curled by hand.) GE's CFL produced as much light as an incandescent, while drawing just 20 per cent as much electricity. But CFLs couldn't be dimmed, they were fragile and they produced a light that had all the warmth and appeal of skimmed milk. Rather than commit the funds to bringing a new technology to market, GE shelved Hammer's design.
In 1980, Philips became the first company to market a CFL, with a design based on a series of bends rather than GE's spiral. But with the 70s energy crisis over, there was little interest. It wasn't until the 90s that CFLs gained traction, driven by concerns about energy efficiency. GE finally put Hammer's spiral into production. And by the mid-2000s, CFLs stood next to incandescents in shops. At first, consumers seemed to embrace the technology, partly because of the advertised energy savings and partly -- in the UK and elsewhere -- because of massive distribution programmes by the energy companies, who were chasing government targets for reduced household consumption and so sent out CFLs to their customers unbidden. But problems of dimming, flicker and light colour were soon noticed. And manufacturer claims of bulb lifetime and quality were exaggerated. Consumers didn't understand that CFLs burn out when they're not allowed to rest at least 15 minutes between being turned off and on, or that they overheat if used in recessed ceiling spots.
Though industry claims that some of the problems resulted from an early influx of cheap imported bulbs are true, many issues remain. No-name commodity bulbs still perform poorly, and even the big brands continue to poison the well by selling, for example, CFL floodlights, which often wind up in outdoor motion-sensor systems.
This is an absolutely inappropriate use, given how fast the bulbs expire when they have to flick on and off quickly. The final blow came when consumers learned that CFLs contain mercury, enough that the UK's Department for Environment, Food and Rural Affairs' instructions for a broken bulb state: "Vacate the room and ventilate it for at least 15 minutes. Do not use a vacuum cleaner, but clean up using rubber gloves and aim to avoid creating and inhaling airborne dust. Sweep up all particles and glass fragments and place in a plastic bag. Wipe the area with a damp cloth, then add that to the bag and seal it. Mercury is hazardous waste and the bag should not be disposed of in the bin. All local councils have an obligation to make arrangements for the disposal of hazardous household waste." Does that sound environmentally friendly?
In the US in 2008, as part of the law mandating the ban on incandescents, the US Department of Energy (DOE) began writing the CFL's obituary by launching a competition intended to jump-start the LED transition. The L Prize (short for Bright Tomorrow Lighting Prize) offered $10 million to the first company to come up with a 60W-equivalent bulb that met a series of standards designed to avert a CFL-like debacle. It would draw no more than 10W, be truly dimmable, flip on and off without flicker or hesitation, and emit a pleasant light. It would also have to fit into a standard socket and last at least 20 years.
The money wouldn't cover the development costs, but the winner would get recognition and, maybe, lucrative government contracts.
In August this year, the DOE announced that Philips -- the only entrant to meet all the competition's requirements -- had won the award for a bulb that "performed exceedingly well through a series of tests and being subjected to various extreme conditions". Switch skipped the prize because creating a bulb with just a 10W draw would, according to Sharenow, drive up prices for consumers and increase the risk for a startup with limited funds. The company's current 60W design draws a still-paltry 13W, well within the confines of the new regulations.
At £18, it won't be cheap. A 60W incandescent costs less than a pound. But the simple fact is that coming up with a worthy LED bulb is complex, requiring expertise in physics, chemistry, optics, design, and manufacturing. Since nobody has built such a multidisciplinary lighting product before, approaches have varied wildly. So have results.
Conventional wisdom has it that only a company with huge resources could come close. But there's another possibility: as with PCs and phones, the massive shift that LEDs represent may open the door to faster-moving entrepreneurs. In the same way that Tesla leapfrogged the superpowers of the automotive industry in the race to develop viable and exciting electric cars, so might a nimble startup take the lead in the transition to solid-state lighting. That's what Alan Salzman, CEO of Vantage Point Capital Partners, is hoping. The firm -- which provided funding for Tesla -- won't give exact numbers, but admits to an eight-figure dollar investment in Switch. "You'll hear it over and over," Salzman says. "When an industry transforms, some incumbents adapt, but a lot don't. That's what's happening in lighting."
GE invented the light-emitting diode in 1962. The first ones to come into wide use -- glowing a space-age red -- turned up in the clock radios, pocket calculators and digital watches of the 70s.
Additional colours and increased brightness required more nuanced control of layer composition and depth. But on their own, not even advanced LEDs can produce anything close to the warm light the human eye desires. There are two ways LED makers create a more pleasant white. In the 90s, the favoured technique was to combine red, green and blue LEDs. But they all have differing efficiencies and operating requirements. Now the (white) LEDs in household applications are blue diodes daubed with a powdered coating called a phosphor, which includes rare-earth elements that filter blue light. The phosphor is generally yellow and, depending on the composition of the phosphor and the ratio of unconverted blue light, the resulting "white" light can range from the warm glow preferred for home use to cooler tints more suited to, say, outdoor use.
Though still rather expensive to produce, LEDs are getting cheaper, just as Haitz's Law predicted, because of both technical advances and economies of scale. They're also getting brighter, which means manufacturers can use fewer per bulb, further driving down costs. Things are advancing so quickly, in fact, that Haitz, now retired, thinks his law will soon expire. Sometime around 2020, he says, bulbs built for our conventional infrastructure will max out, since at some point additional brightness from a single socket would be overkill. "We'll reach a limit where we can move forward only by producing quantities of luminous flux that nobody needs," he says. After that, progress would continue only if the Edison socket disappeared and the world moved away from bulbs altogether -- most likely to flat-panel LEDs, he says. LEDs are point lighting sources; they shine in only one direction. That makes them fine for floodlights or traffic signs. But for LEDs to replace the Edison bulb, the shape of light they emit has to be round. Once you've got that, you also need a driver to control the individual diodes, which means additional circuitry and firmware. So far, putting all those elements into a single, affordable package has proven to be an immense challenge.
Ron Lenk -- an MIT-trained physicist who was working at a semiconductor company-founded SuperBulbs in 2007. In his patent filing he described a new technology that might solve the heat and shape problems of LED bulbs. His bulb would "use a thermally conductive fluid, gel, or plastic" to "act as the means to transfer the heat power generated by the LEDs". Working out of their home in Redwood City, California, Lenk and his wife Carol, an electrical engineer, began constructing prototypes using raw LEDs attached directly to a power source and mounted inside baby-food jars. It took two years for the couple to arrive at what they believed was a working coolant, a gel similar to the superabsorbent polymers used in disposable nappies.
Drawing on their personal savings, the Lenks built working prototypes and hired a VP of marketing, Ethan Thorman, to help to get them off the ground. He suggested a consultation with a member of his theatre group: Brett Sharenow. Thorman knew that Sharenow was a trained chemist with an MBA who had spent two decades as a consultant to tech firms such as Pacific Bell and Verio. Sharenow began working with the Lenks in February 2008. In May, he took a prototype to Las Vegas. There he met George Abittan, whose company Advanced Lighting and Electric Service supplies lighting products to hotels and casinos. Abittan led Sharenow to a table that had three bulb fixtures mounted on it. One held an incandescent bulb, another a CFL. The third was for Sharenow's LED.
The SuperBulb's light was so good, Sharenow says, that Abittan didn't believe it actually used solid-state technology. If a product like that could be mass-produced, Abittan said, every casino in Las Vegas would buy in.
Sharenow and the Lenks had already been through several rounds of talks with VantagePoint, the venture-capital firm run by Alan Salzman. On the heels of their successful trip to Vegas, they finally got their funding. Sharenow and the Lenks now had backing, a business plan and a working prototype. But prototypes aren't products. And the SuperBulb, as a product, was turn- ing out to have some problems.
In February 2009, David Horn, a physicist and engineer who'd trained at California's Lawrence Livermore National Laboratory, joined SuperBulbs as CTO. His first act was to test the existing 40W prototype, which at that point was all SuperBulbs had. What he discovered was disappointing. To shake up the industry, SuperBulbs' designs would need to be the equivalent of 60W and higher. But when Horn touched the glass part of the bulb, he felt no heat. The cooling wasn't sufficient to scale up to a 60W equivalent.
In the Lenk design, gel fills the glass shell, transferring the heat from the LEDs outwards, through conduction. A bulb cooled this way should have a dome that's hot to the touch. That the SuperBulb didn't suggested to Horn that the gel wasn't an effective coolant, which would mean nearly all of the bulb's thermal energy was being dissipated via the aluminium heat sink at the bottom. Heat sinks work -- they're standard on most LED designs -- but the idea with the gel was to find something more efficient, since a better coolant would allow more power to be pumped through each LED. That would mean fewer LEDs per bulb, which is how SuperBulbs would hit the lower prices at the centre of the company's business plan.
A series of tests confirmed Horn's suspicions. The gel wasn't doing the trick. So he began experimenting with liquids. The liquids worked, but the gel retained important advantages. It was non-toxic and inexpensive, and it had wonderful diffusion qualities that the liquids couldn't match.
By now, SuperBulbs was nearly broke. VantagePoint's initial investment had allowed the company to grow to 12 employees. Now half had to be laid off. Horn reported back to the capital firm that the product still had a chance, but only if it got new money to fund research into finding a liquid coolant less viscous than the gel. The Lenks left the company in late 2009 (though Carol worked as an adviser for a few more months). The couple remains on good terms with Switch and, as shareholders, stand to profit if the company succeeds. But SuperBulbs, now just Share now, Horn and four employees, dropped into what Share now calls "stealth mode".
In September that year, as Horn continued searching for the ideal coolant, Philips submitted its own bulb for the L Prize.
Then, in May 2010, the world's biggest lighting company announced that a slightly less energy-efficient version of its L Prize candidate, called the AmbientLED (or The EnduraLED in some markets), would soon appear in stores. Priced at $40, it's the only 60W-equivalent LED (with 12.5W draw) that people can buy.
The Philips bulb looks nothing like the Switch. Whereas the Switch looks like it could have been plucked from the set of Fritz Lang's Metropolis, the AmbientLED has an industrial, almost steampunk aesthetic.
A cast-aluminium heat sink extends up from the socket threads, taking up almost half of the 10cm height. It's also more conical than traditional incandescents. But what's most striking about it is that it has no bulb. "This category of product works so differently from incandescents or fluorescents," says Kelly Gordon, a programme manager for the US Department of Energy's Pacific Northwest National Laboratory, which co-ordinates L Prize evaluations. "Test methods need to be entirely different." Gordon breaks the protocols into four categories: longevity, colour, amount of light, and shape of the light. An L Prize contestant is required to submit 2,000 bulbs. The biggest testing hurdle is longevity: LEDs don't simply burn out. Instead, they fade. The current standard, called L70, refers to the point at which an LED is able to generate only 70 percent of the light it originally produced. The L Prize criteria require a minimum of 25,000 hours before L70. That's roughly three years of continuous use, more than two decades if the bulb is used for three hours daily, about the average. "Our first prototypes lasted only a few hours," Horn says. "We'd leave lights burning on Friday and come in Monday to find them dead." Over seven months, he tried more than 200 liquid coolants, from mineral oil to antifreeze-type glycols. None had the right mix of consistency, diffusion, and price.
Horn began mixing earlier coolants together, trying to see if a blend, rather than a single base substance, would do the trick. In October 2009, he hit on a work- ing brew. Switch won't reveal what's in the proprietary mix, other than to say that it's cheap and environmentally clean. "You can clean it up with an ordinary paper towel," Horn says.
The rest of the final design -- the heat sink, drivers and shape -- came together relatively quickly, he says. The bulb's ten diodes, each with a yellow phosphor, sit along a halo of aluminium fingers. That ring of light contributes substantially to the bulb's design appeal, but it also helps create a very incandescent-like light shape.
Today, Horn says, there are bulbs in his offices that haven't been switched off since August 2010. In April 2011, the company formerly known as SuperBulbs announced its new name, starting the coming-out party that continued at Lightfair and will culminate in October, Sharenow says, when Switch comes to market with its 60W-equivalent bulb, followed by a 75W offering in November and a 100W model in February 2012. "Those bulbs will change the world," says Brett Sharenow.
This article was originally published by WIRED UK
