SAN JOSE -- Could Michele Bachmann be right about advanced lighting technology?
Congresswoman Bachmann, former Republican presidential hopeful, has led a campaign for several years in defense of the historic Tom Edison-style incandescent lightbulb, against government pressure for consumers to adopt new, more energy-efficient lighting solutions.
Michael Poplawski, meanwhile, has led one of the government’s teams – at the Pacific Northwest National Laboratory – seeking to solve issues that currently hobble the widespread deployment of LED (Light Emitting Diode) technology, which remains both more expensive and far more efficient than Rep. Bachmann’s beloved tungsten-filament vacuum tube.
“Complicated,” was the commonest word from Poplawski, senior energy engineer at the Portland, Oregon national lab, as he spoke to a session at the DESIGN West conference here Tuesday. He cited numerous complications in the effective use by consumers of LED lighting, and obstacles to reducing costs for the technology.
One of the points Poplawski stressed was that every LED light is a solid-state (SSL) electronic device, while a lightbulb is just, well, a lightbulb. In a presentation that exceeded its planned duration by some 30 minutes, Poplawski dwelt on four problems that his group is working to resolve: flicker, dimmability, power quality, and lifetime limitations linked to “driver reliability.”
Flicker, for example, is not just a relative of the yellow-bellied sapsucker.
Flicker is inherent in every form of electric lighting and it affects everyone differently, according to individual levels of visual sensitivity. “A good chunk of people,” said Poplawski, with a measure of awe, “are seeing things (flicker) at upwards of a thousand hertz.” Flicker’s biggest moment in the limelight occurred in the film, “The Andromeda Strain,” when the stroboscopic flashing of a laboratory light caused one of the characters to suffer an epileptic seizure.
Poplawski mentioned the danger of seizures, and added other side-effects of flicker, including headaches, fatigue, blurred vision, eye strain, reduced visual task performance and distraction on the job.
The good news about LED lighting is that it can reduce flicker, especially compared to standard fluorescent lights. The bad news is a determination by researchers that flicker – which is consistent and predictable in current lighting systems – is more “complicated” in SSL. It tends to vary substantially, both in amplitude and frequency, in various LED bulbs.
Among the solutions Poplawski’s national lab is exploring is the development of LED solutions with minimal flicker, which requires researchers to identify and measure qualitatively (in terms of human reaction) the presence of flicker. In the end, flicker must be measurable in a way that its level can be reported to consumers in a way they’ll understand it.
Among other issues with which Poplawski’s team is wrestling is dimmability. Many homes are equipped with dimmers, virtually all of them designed to dim conventional incandescent and fluorescent lights. The difficulties of designing LED bulbs that react to existing dimming technologies required Poplawski 20 minutes to explain. The adaptation is not easy. Poplawski boiled it down to the fact that consumers don’t know what will happen when they use their twentieth-century dimmer to soften the glare from a post-millenial high-tech bulb. “There’s no predictability today,” said Poplawski. “We operate in a built world with existing products and there, the challenges are significant.”
Similarly difficult is the issue of power quality, the consistency of power flow into the home and its lighting system. “Events” like lightning strikes and power surges can affect LED lights in different ways than they impact older systems. Moreover, the addition of SSL networks to existing power, cable TV and telephone networks – often clustered together on the same utility poles – can result in interference that compromises one or all of the networks.
Poplawski also cited the problem of “driver reliability.” Old-fashioned “drivers” – or lamps -- are often inappropriate vehicles for new-fashioned LED bulbs, causing problems like overheating that can shorten the operating life of the new bulbs. If the bulbs blow out earlier than promised, the advantage of the new technology shrinks significantly.
Indeed, thousands of new bulbs screwed into old sockets and ancient sconces have died well before their predicted demise, souring many consumers, especially the Congresswoman from Minnesota, on the promise of LED lighting. “You don’t know,” lamented Poplawski, “where people are going to stick things.”
In the end, Poplawski found himself suggesting an infrastructure problem similar to that hindering the use of electric automobiles. The installed power-supply base is incompatible with the new forms of power.
President George W. Bush launched the lightbulb wars in America by signing the Energy Independence and Security Act of 2007, which recommended a phase-out of the tungsten-filament bulb. Five years later, however, Rep. Bachmann’s cherished GE Soft-White is still ubiquitous in the land. Apparently, it will remain so for many years to come, glowing wastefully beneath dusty shades in graceful but obsolete drivers (lamps).
Things like this should only be driven by the market. If you make a better mouse trap, the world will beat a path to your door. As soon as it is more economical for me to buy SSL, I will switch. Until then, you know who will be getting my hard earned dollars. For the government to step in and mandate the change is just more of our liberties evaporating.
The market change to SSL lighting is, contrary to public and misinformed opinion, not government mandated on a national level, but subscribed to a global convention. The incandescent light bulb is not banned, but at the end of it's production in countries around the world. When countries such as China can make the change to SSL or the less expensive CFL technology due to the huge advantages for energy and the dependence on non-renewable energy, they now set the example while we, the US believe everything is big government and an infringement of our rights. We live in a global world. Turn on your computer and look around sometime.
I think SSL will be the future considering the fact that it offers many advantages like power saving and longer term reliability. But at the same the infrastructure around the power generation and distribution also shall be improved.
LEDAgree, my computer is on, as is the case for anyone who is reading this (not a very perceptive suggestion, by the way!). What global world should we join? One of Europe, where econonies are stifled under the growing beaucratic state? One of China, where freedom is a concept that may develop in the future? I choose neither, and I hope many more do the same in November.
In the US, incandescent bulbs are being phased out by law by wattage (I'd call that "banned") in the US. 100W was phased out in CA last year, and is phasing out in the rest of the US this year per congressional mandate. Next year comes 75W, and so on (all part of the same bill, already passed). Not sure what sort of linguistic contortion LEDAgree is attempting...technically the bulb itself is not banned, just the sale of it. Stores can still sell their stock, so it will take several months to see the effect. If you want to make your own bulbs, go ahead, I think that is legal. You just can't sell them or buy them. Ok, you're right, not banned. The wording in the legislation is a little obscure for most people - it sets lumens/watt minimums rather than "banning" incandescent, but the effect is the same. You won't be able to buy 100W, 75W, etc. incandenscent bulbs. And yes, the lower wattages are not banned for now. How many 40W bulbs do you have in your household lighting? You've got a few years left before those no longer meet the lumens/watt requirements in the passed legislation. Enjoy the dim light, at least it doesn't flicker.
I personally like that I can screw in a bulb, not have any flicker, and dim it with a simple, inexpensive, old-fashioned, voltage-varying slider switch. I am baffled at why Michelle Bachman is pillorized for supporting the freedom to buy a darn light bulb. Seems even more bizarre to me that congress acted to ban light bulbs.
The banning of the 100W and 75W light bulb has been done without fanfare, because those who support it are hoping the majority of the country simply doesn't notice. I suggest you write your congressman, and respond vociferously to silly, distorted posts that characterize banning light bulbs as a failure to follow the great example of China. When did it become seditious to sell 100W light bulbs in the US? Last year in CA, Oct 2012 in the US (after a short reprieve pushed through by Bachman's evil cohorts) in the rest of the country. Google it.
Don't buy into the semantic distortions, or the attempts to characterize supporters of economic freedom as Luddites. The real Luddites are those who don't believe in letting AS's invisible hand do its work. Turn off your computer for a bit and read an economics book.LEDAgree, my computer is on, as is the case for anyone who is reading this (not a very perceptive suggestion, by the way!). What global world should we join? One of Europe, where econonies are stifled under the growing beaucratic state? One of China, where freedom is a concept that may develop in the future? I choose neither, and I hope many more do the same in November.
The author has discussed about the effects of flicker coming out of the light bulbs. It is very true. I compared the 4 ft tube light with inductive ballast and with electronic ballast. I found there is a great comfort my eyes felt with electronic ballast generally this works around 40 kHz. Because the light has high frequency flicker which is not detected by the eyes. The inductive ballast works at line frequency 50 or 60 hZ give us visible flicker. A LED light generally works on PWM principle at a higher frequency than the line frequency and so the flicker problem is minimum or not visible at all.
@agk I agree completely. I had never heard or thought of led flicker being an issue at the frequency they operate at. Why are they wasting time on this.
Also why be overly concerned about making leds fit traditional fittings. Light fittings, not just the bulbs that fit them have limited lifetimes as well.
Many people update them when they paint a room
and a lot of fittings actually fail from the heat of incandescents.
If you can buy a whole fitting with led lamp for the price of an led bulb that fits bc or edison screw fittings. I know I'd rather have a whole fitting.
With the proliferation of fluroscent fitting formats in the past 20 years and add to that the halogen formats etc I wonder whether it is more of importance to build an led bulb for performance and reliability than be concerned about backward compatability.
You only need to look at handheld torches to see nobody was concerned about throwing out their old incandescent torches for the bright new led torches available.
I am much less concerned with the flickering as I am with the short life and high costs for the LEDs. The day to day annoying issue that I have run into with a number of the LED lights is the high frequency whine that the power conversion circuit generates. This is really a background but hard to ignore noise. The dimming issue is a bother but never bulbs can be dimmed (not sure how they are doing it, I don't own any). I went out and bought a 4 pack of 100W good old fashioned light bulbs just to have them. I resent the nanny state regulating things that directly impact me and wish the government would allow the free market to drive innovation and improvements not silly laws.
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