Slashdot Mirror
Nanotech Could Make Incandescent Light Bulbs As Efficient As LEDs (sciencemag.org)
sciencehabit writes: Thomas Edison would be pleased. Researchers have come up with a way to dramatically improve the efficiency of his signature invention, the incandescent light bulb. The approach uses nanoengineered mirrors to recycle much of the heat produced by the filament and convert it into additional visible light. The new-age incandescents are still far from a commercial product, but their efficiency is already nearly as good as commercial LED bulbs, while still maintaining a warm old-fashioned glow.
I can't wait to get back to the days of changing each light bulb in my house a couple of times each year.
What's the lifetime of the new incandescent bulb? Do they still burn out as fast as they used to? Or does recycling the heat cause them to take longer to burn out. The major advantage I find in LEDs is that they last a long time. And with the plummeting prices (picked some up for $3.50 a piece at Walmart last week), It's going to be hard for incandescent bulbs to compete. If this was such a good solution, it could probably be used for LED lights as well, since they throw off a non-negligible amount of heat as well.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
They mean warm in the sense of color temperature (yellowish).
XML is like violence. If it doesn't solve the problem, use more.
They did legislate efficiencies.
https://en.wikipedia.org/wiki/...
So if they can make an incandescent that meets those requirements, who cares. Now go make another grievously uninformed post.
Aside from questions of longevity, I honestly much prefer the availability of light color options that LEDs provide. After getting several LEDs that are substantially cooler in color than normally available incandescents/CFLs, I never want to go back. Add to that the fact that I can GET warmer colored LEDs if I desire, and the fact that I can use LED lights that package other abilities into their package (like wireless speakers), and I just don't see the consumer draw other than some rose colored glasses. (Maybe for dimmable bulbs, which I know LEDs struggled with for awhile but they seem to have overcome that also... This also ignores the brightness of the lightbulb, as LEDs have just generally been brighter [a good thing imo] than comparable incandescents and CFLs in my experience. Maybe the new tech solves that, but still probably not worth it as a consumer is my feeling.)
The question isn't just whether they'll be as efficient as LEDs. The question is whether they'll last as long and cost as little.
Frankly, for most people, what they liked about incandescents was their cost. I seriously doubt that anything that requires "nanoengineered mirrors" will cost $2.50 for a pack of 10.
Dan Aris
Fun. Free. Online. RPG. BattleMaster.
There are some crazy innovations happening in LED lighting. To the point where stock on shelves is becoming obsolete in a matter of months.
All white LEDs are essentially florescent lamps. - A blue-range LED excites a phosphor that makes white light. You can tune the phosphor mix to get whatever color range you want. "Warm" Led lights are completely indistinguishable from incandescent, and in may cases can be "Warmer"
So basically you have an emitter with a glob on tob.
In the past everyone was focusing on getting the emitter more powerful, and putting one or two in a light.
That approach is completely obsolete - Too much heat in a tiny space, extremely high drive current requiring more expensive power supplies, light comes from a single point source. (Single emitter is good for some applications but for home lighting its not great)
Now they've developed chip-on-glass techniques that lay down lots of tiny LEDs on a strip of glass which are all then wired in serries, then are covered in a soft polymer that contains the phosphor. The polymer both protects the chips and their wiring while providing a large surface area to emit white light.
The strip arrays are cheap to make (completely automated) and guess what happens when you power a bunch of strips in series (About 80-200 chips at a time)? You can drive it at like 60-100 volts. At that voltage the power supplies are CHEAP because you're only drawing a few hundred ma. Everything gets cheaper and more efficient.
So let us give these guys a well deserved PhD or Masters as the case may be and move on...
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Incandescent lights were not banned, efficiency standards were passed that rules them out for most uses. They would be allowed for general lighting if they could be efficient enough, and they are still being allowed and used for some applications like harsh environments, certain decorative uses, heating, etc.
Depends on the state and/or country. Many states/countries banned incandescent bulbs. California almost did, until they were excoriated by environmentalists and economists, saying that only efficiency levels should be regulated.
Peter predicted that you would "deliberately forget" creation 2000 years ago...
I've had multiple led bulbs die in under two years.
Stop buying them from the Dollar Store reject sale bin.
Paid $10 for a 60 watt equivalent at Home Depot. Supposed to last 10 years it claimed. It was about as bright as a 25 watt incandescent and stopped working after a month. It was in a normal table lamp so airflow was not a problem. The warranty said I needed my store receipt. I shouldn't have to keep and file away store receipts for something as ubiquitous as a fucking light bulb. Into the trash it went.
Only the State obtains its revenue by coercion. - Murray Rothbard
In every case I know, you can still get the incandescents - they just can't be 'general use' bulbs. 40W appliance bulbs are still available for environments like your oven. Short of halogen bulbs(which are actually a variation on incandescent), no other lighting technology can withstand the heat well enough.
Otherwise, you'd have to get fancy with a light pipe or something in order to keep the light generator cool enough, and even then you might have problems during things like self-clean cycles. In the end, it's just not worth it, the light isn't on that much, and most of the time you're heating the inside with electricity anyways, so it's not like bulb efficiency really matters.
I don't read AC A human right
Thomas Edison didn't invent much of anything...he just patented the inventions that his staff came up with.
He would only be pleased by this technology if he could get a patent on it. Otherwise, he would probably campaign to squash it, as he did with many of Tesla's awesome inventions.
I'd go urinate on Edison's grave, but that asshole isn't worth the trip out.
LED bulb nerds should checkout bigclivedotcom's channel on YouTube. Where he does teardowns of LED light bulbs purchased on eBay and from his local "pound shop" and other assorted cheap Chinese crap.
Here he does a teardown on what sounds like your "chip-on-glass" LED bulb. He approves of it.
As others have mentioned: color, not actual heat produced.
One thing that LEDs aren't emulating (yet) is the nature of a dimming incandescent where the color gets more yellow-red as you dim the light. LEDs will pick a "color temperature" and that's it, regardless of dimming.
Not necessarily true. I recently bought some dimmable LED bulbs that feature getting redder as you dim them. I assume they do this by monitoring the incoming waveform and tweaking the power to different colored elements inside.
I didn't even notice the feature on the package until after I got them home, but I tried one in a dimmable fixture to test it out, and it worked better than I expected (although the bulb still couldn't be dimmed down quite as far as a real incandescent before dropping to zero output).
From The Fine Article;
... ultimately improved the efficiency of the bulb to 6.6% ...
6.6% is 45 lumens per watt.
Pardon me while I yawn.
This tech might lead to something interesting, but so far, not so much.
The commercially available Cree soft white 4-flow A19 bulb is 12% or 82 lumens per watt.
There are LED modules for sale that are over 200 lumens per watt.
In the lab, 303 lumens per watt (44%) has been achieved.
He didn't invent the light bulb, and he didn't invent that, either.
He and his team invented a long-lived, high-impedance, incandescent lamp that could be wired in parallel --
as well as developing a complete and commercially viable system for safely electrifying your home our shop. Including the training of a new generation of electricians.
There actually is a good argument to be made for changing the color temperature with the amount of light output.
Take a look at the Kruithof Curve: https://en.wikipedia.org/wiki/...
Humans are used to see higher color temperature (i.e. more bluish light) in brighter environments. This naturally mimics the light around noon time. We are also used to see lower color temperatures (i.e. more yellow'ish light) in darker environments. This would mimic the light during dawn and dusk.
If the color temperature indoors doesn't match these expectations, we often feel uncomfortable. This is the reason why office environments often opt for more bluish lights; they also tend to run everything at much higher brightness. And restaurants are often kept darker and then the color temperature is adjusted towards a more yellow'ish tint. If you get this wrong (e.g. install bluish neon lights in a dimly lit corridor), it is blatantly obvious that something is wrong. Similarly, if you install lots and lots of yellowish lights, most people complain that things are unnaturally yellow.
With incandescent lights, we never had this much control, and people mostly got it right by installing the right number of light fixtures, and or the right type of light fixture (i.e. light bulb vs. halogen light vs. fluorescent tube). With LED lights, there is a lot more control; but that also means there is a lot more that can go wrong, if you don't pick the right temperature when buying the lights.
And to get back to your original question, yes, a dimmer that also adjusted the color temperature would be very nice to have. And with RGB-style LED lights, that's in principle possible to do. I haven't actually seen a product targeted at your average consumer that does this though.
You're not alone. My whole house is "White" 7000k leds. When you first install them into places where you used to have yellow they can look stark and clinical initially. But in a day you are used to it and the yellow starts to look dirty in comparison. I think the reason so many people want the yellow lights is it is what they are used to.
Another nice side effect of have white lights is if it is a bit dull and dreary outside turning your lights on makes it feel like the day is brighter, rather than making you feel the lights are on.
Name names! Some companies make complete junk products, others don't.
Lights of America make complete and utter junk.
Cree (in addition to being huge in the actual LED elements) makes bulbs in a very nice form factor, and they do put off a very nice color (for emulating incandescent) and I think a comparable amount of light. Unfortunately they seem to be the golden child of tech reviews that circle jerk about how great they are. Downsides? I see higher than average failures from real-world reports, yes they have a 10 year warranty, but you have to pay shipping, and they buzz like a mofo on a dimmer.
Phillips. I still have a Phillips CFL from 15 years ago (with three arch tubes) that hasn't died yet. Well I doubt their new product line has the same longevity, I'm reasonably satisfied with them as a brand. The Philips "SlimStyle" seems to be a good low end LED light. It looks strange but has decent light distribution, OK color, fewer failures than Cree from field reports, and a good price. Downside is they buzz in dimmers too (though not as bad as the Cree), but seem silent in normal lamps.
I think he means that when you dim an incandescent, it's thermodynamic temperature is cooler. The filament shifts from a shade of white towards the red, creating a color temperature that is warmer.
LED bulbs are superior to everything else, prove me wrong. (you can't)
I put an LED bulb in my Lava Lamp. Now the goo just sits there on the bottom.
Have gnu, will travel.
Why would anyone prefer warm yellow light? That was a byproduct of incandescent light, not a design choice. I for one hate the way it made everything look dirty and yellow. Give me white light (3500-4000K) any time.
I mean, by the time you've gotten your infrared reflector photonic crystal tungsten ribbon rectangular emitter Rube Goldberg thing perfected, it's bound to be a lot more expensive than current incandescent bulbs, and probably more expensive than LED bulbs. Plus, it is still working by getting a thin piece of metal hot enough to glow brightly. That inevitably means limited lifespan.
Personally, I buy cheap LED bulbs when I see them on sale, and I haven't had one fail yet. Other than the older silicone-rubber-over-glass Cree bulb which I dropped. It still works fine, actually, but with electrically 'hot' bits exposed, I'm not running it.
I don't know from spectrum, but I got a lot of pushback on installing CFLs. This has not been an issue with the LEDs I've gotten; they seem to have a good WAF (Wife Acceptance Factor) whatever their "spectrum" might be.
The big problem with LEDs might turn out to be they just don't die. Once everyone has replaced every bulb with an LED, who's going to be buying bulbs?
What I'm wanting to see is more fixtures that are built with LEDs, rather than assuming people are going to have to replace bulbs constantly.
Depends on the state and/or country. Many states/countries banned incandescent bulbs. California almost did, until they were excoriated by environmentalists and economists, saying that only efficiency levels should be regulated.
No, California banned the Edison socket. More precisely, any light with an Edison socket is treated as low-efficiency lighting, presumably on the theory that someone could screw a low-efficiency light bulb in such a socket. It's really stupid to have done so, because now many people are stuck with lighting that only accepts compact fluorescent and the like, while those who have Edison sockets can easily upgrade to the latest and greatest LEDs. There's a loophole, as Edison-socketed lighting is permitted in rooms other than the kitchen, so long as a dimmer switch is in the circuit. This can be even worse, because many high-efficiency lights that fit in Edison sockets are damaged by poorly-designed dimmers.
Phillips. I still have a Phillips CFL from 15 years ago (with three arch tubes) that hasn't died yet.
They would probably like to buy it from you so they can figure out what went wrong with it not dying, so they can prevent it happening again...
Edison's team invented the first long-lasting and efficient (relatively speaking) lightbulb. Thus, this nanotech -- if it works -- would obsolete his invention. Also, it is probable that we can use nanotech to create flying pigs.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
A similar method was reported here back in 2002.
It would be good to have a light source that gives a full, even spectrum again.
As others have commented here, I also wonder about the longevity.
I believe that current incandescent bulbs fail mostly as a result of heat. These new bulbs, if they do run cooler would need to be designed with a completely different impedance model, since traditional incandescent bulbs run a delicate balance using heat and the resulting impedance to maintain some kind of equilibrium. This is why they most often fail immediately after being switched on - the bulb is cool (low resistance) so for a brief moment there is a large amount of current flowing through the filament before it heats up enough to reduce the current to a safer level. If that spike happens to coincide with a peak of the AC waveform then the filament, already weakened by many heating/cooling cycles, stands a good chance of burning out.
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
I started out with 15 fixtures with Cree bulbs. I suffered from 1 completely failed bulb, one bulb that randomly changed between full and half brightness (and so had to be replaced), one bulb that sputters frequently, and a few others that sputter occasionally. Some of these bulbs are relatively new (the one that sputters frequently was bought less than a year ago) while others are first-gen bulbs from when they first launched in Canada.
Two other fixtures have Ikea LED bulbs in them, and have not had any issues at all. A few months ago, I replaced three of the Cree bulbs with Walmart bulbs, since one of the three Cree bulbs had failed, and Cree bulbs are very poorly diffused so it resulted in very unpleasant hotspots in the translucent fixture.
My Cree bulbs are not all one kind. I've got 40W, 60W, 100W, and PAR. The 40W bulbs haven't had any issues that I can recall, while the 60W seem iffy, and the 100W seem pretty much gauranteed to fail quickly. None of these are in closed fixtures, and many of them are completely bare.
So, you can imagine that my opinion on Cree bulbs is not all that favourable, having owned that many, and had that much trouble with them.
If this was such a good solution, it could probably be used for LED lights as well
No. Incandescent filaments have to be hot to produce light, but with its entirely different mechanism, reflecting infrared back onto a light-emitting diode will not help it produce more light. Heat is NOT good for the diode. LED bulb designs actively do the opposite of these nanomirrors: they transfer heat away from the diode. (You may have noticed the fins on some LED bulbs. Their purpose is to radiate heat and keep the diode cooler.)
That that is is that that that that is not is not.
Your point is valid, but the hand-drawn spectrogram you cite is well out of date. This is closer to the state of commercial art. http://www.designingwithleds.com/review-hands-cree-linear-led-t8-fluorescent-replacement-lamp/
Contribute to civilization: ari.aynrand.org/donate
i endorse big clive.