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Making Strides Toward Low-Cost LED Lighting 398

Posted by timothy
from the brightly-walk-among-the-clouds dept.
Roland Piquepaille writes "You all know that incandescent bulbs are pretty inefficient, converting only 10% of electricity into light — and 90% into heat. Light-emitting diodes, or LEDs, could soon replace incandescent and compact fluorescent bulbs in our homes. They are more efficient and environmentally friendly. But LED lights are currently too expensive because they are using a sapphire-based technology. Now, Purdue University researchers have found a way to build low-cost and bright LEDs for home lighting. According to the researchers, the LED lights now on the market cost about $100 while LED lights based on their new technology could be commercially available within a couple of years for a cost of about $5. It would also help to cut our electricity bill by about 10%."
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Making Strides Toward Low-Cost LED Lighting

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  • I thought one of the major obstacles of using LED lights was that they weren't actually very white, but rather a shade of light blue? Has there been some major advance in creating white LEDs that I just happened to miss out on (serious question btw)?
    And if so, just how white ARE these super cheap LEDs?

    • by TheLink (130905) on Sunday July 20, 2008 @02:48PM (#24264565) Journal
      Many of these white LEDs are blue or UV LEDs that stimulate a phosphor coating to produce white light.

      Having three Red Green Blue LEDs to create white light might produce a light that appears white to the eye, but might not have the same effect when reflected off material.

      The white from the phosphor would generate more of a broad spectrum white, whereas the Red, Green and Blue LEDs would probably create spikes in the Red, Green and Blue spectrum.

      So you might have a green material that appears black when you use the "RGB white" LED - just because it does not reflect the Green LED's narrow green, whereas it will appear green in the white from the phosphor white LED.

      The phosphor means one more step in light conversion, and that probably means less efficiency.
      • Re: (Score:2, Interesting)

        by sdpuppy (898535)
        Phosphor? Thats a bit disappointing. While I haven't followed the field much, I would have expected that they would have have come up with a way to make a variable band gap so you have electrons jumping back and forth over a wide range of frequencies.

        Another thing I imagine might be to make the LED as an integrated circuit - an array of LEDS with each junction a slightly different gap than the preceding, so while you don't really get a true continuum, a few million different colors would be awfully clos

      • by De Lemming (227104) on Sunday July 20, 2008 @03:58PM (#24265161) Homepage

        As far as I know, the most used variant is the blue LED + yellow phosphor one. In this case, the blue light, emitted by the LED, is cast directly, besides the yellow light coming from the phosphor. The mix of blue and yellow produces white light.

        Unfortunately, these LEDs don't produce a very broad spectrum of light either. The spectrum has a sharp peak in the blue range, and a bit broader yellow range, as can be seen on this graph on the Wikipedia page [wikipedia.org].

    • I am going to be very upset if I can't get incandescent anymore. Yes, they take more energy, but they are worth it... the bright white, unnatural light gives me a headache and causes my eyes to strain much faster when I am working under it for a long period of time. I never have this problem at home, with my "regular" lighting, only here at work under the fluorescents. I have heard this is at least partially due to the flicker rate. Would the LEDs pose this same problem?
      • Re: (Score:3, Informative)

        by gardyloo (512791)

        I would have absolutely agreed a few years ago. Traditional fluorescents hurt my eyes after a while, and incandescents are slightly warmer, and yellower, like natural light. However, the new compact fluorescents are awfully good, and with certain ones I can't tell the difference between them and incandescent bulbs.

      • LEDs are constant outflow, like incandescents. There is no flicker at all.

        A lot of people who experience headaches under fluorescent bulbs are able to fix it by adjusting the refresh rate of their CRT screens, as the 60Hz flicker and 60Hz refresh rate can cause discomfort. If you have an LCD, you're out of luck, but if you have a CRT and can get a refresh rate of 75 or above, it may help alleviate the pain somewhat.

        • I have an LCD monitor, in fact, I use the exact same one here at work as I have at home, because I wanted to determine what was causing my problem. After a few hours staring at this screen, my distance vision gets awfully blurry. A visit to the eye doctor told me my vision is fine but my eyes are getting strained, and I got some glasses to help reduce this. But at home, sitting the same distance from the same type of screen for the same amount of time, I have no trouble with the same distance vision. The on
        • by nmg196 (184961) *

          > LEDs are constant outflow, like incandescents.

          No they're not. That's only true if you run them off DC.

          This article is all about replacing light bulbs - and normal light bulbs run of AC, so LEDs will flicker just as much as florescent lighting. They're also diodes, which theoretically means that they would normally flicker twice as much. However I think they put two sets of LEDs in to counteract that effect and probably some voltage smoothing capacitors.

      • by funaho (42567)

        I too have a real problem with standard fluorescents, but I use CFLs almost everywhere at home and find them quite comfortable. They don't flicker and they have a warm, pleasant color spectrum.

      • by shmlco (594907)

        "... the bright white, unnatural light gives me a headache..."

        Yeah, because heating tungsten to over 2000 degrees K is so "natural" in and as of itself....

      • by Arterion (941661)

        I don't get it.

        First off, the color temperature of most "soft white" CFL's is not even 3000K. Normal incandescent bulbs give off light at about the same color. You can get "cool white" CFLs, though they are much less common, which give off light at around 4100K.

        Both of these are much, much warmer than natural sunlight, which is usually over 6000K.

        I see this argument a lot against CFLs, and fluorescent lighting in general. People describe it as "blue" or having an "unnatural color", but that's not really

  • Light vs. heat scale (Score:3, Interesting)

    by WhoIsThePumaman (1182087) on Sunday July 20, 2008 @02:47PM (#24264553)
    I'd be interested to see a progression timeline of the light vs. heat ratio from the various methods we've used. I'd imagine candle and torches would be the heaviest on the heat side, but seeing it slide with gas lamps, lanterns, incandescents, CFLs, and now LEDs would be neat. Anyone have some spare time on their hands?
  • LED = Luxury Goods (Score:5, Interesting)

    by cdrguru (88047) on Sunday July 20, 2008 @02:48PM (#24264563) Homepage

    Take a hint from the car manufacturers. Today, high-end cars are using LED tail lights. They are also used on trucks. The main advantage is they do not burn out.

    However, for most people in the world a burned-out tail light bulb is a minor safety issue and a minor expense. Replacing the bulb takes 10 minutes and maybe the owner's manual if you are truely clueless about how to do it. Also, many people own a car for 5+ years without ever having to replace a single bulb.

    Compare this to the cost of a minor traffic accident where a tail light is cracked. No, you cannot replace the lens or any individual part, just the whole assembly. Instead of $100-$200 for an incandescent bulb assembly expect to pay $1500-$2000 for the LED tail light.

    Sure, over the life of many vehicles it is a minor issue that bulbs will never burn out. But over the same number of vehicles it is far, far more likely that a lamp assembly will have to be replaced. The result is a far more expensive part to replace.

    With trucks there is a certain amount of sense to be made with claiming that the bulbs do not have to be replaced. Replacing a bulb on a truck or semi-trailer can be a real hassle requiring a ladder and tools. However, again the likelyhood the bulb would ever need to be replaced vs. the lens being damaged is about the same as for cars. Basically, it is a complete rip-off.

    Expect to see wired-in LED systems in household lamps where the fixture must be replaced because the bulbs cannot be. Expect to see the fixtures sold to builders with non-replacable bulbs will cost the builder only slightly more when bought in huge quantities but the homeowner will be faced with $1000 lamp fixtures should they ever need or desire to replace them.

    • This is certainly an interesting post and a consequence most of us probably haven't considered yet. I'm definitely going to check before investing in any of these lamps how easy it is to replace the light or if its the entire fixture. Kind of kills the whole idea of environmental friendliness. If some manufacturers choose to do this, I will boycott their products.

    • Re: (Score:3, Interesting)

      by ModernGeek (601932)
      I have noticed that with LEDs, they are brighter than a comparable halogen bulb + filter, but they do not light up the surrounding area as well. I have an LED lightbar on top of my vehicle (volunteer firefighter), and the lights are brighter, but compared to a halogen lightbar, it does not light up the area with red and white the same. It is definitely more visible though. That is why I think LEDs might be good for taillights and such, but probably not for headlights.
      • Re: (Score:3, Informative)

        by pimpimpim (811140)
        Same here. When I drive behind a car with LED taillights, the focussed light of the LED creates a memory effect in my eye and the spots remain visible even when I blink. This is very irritating, because natural instinct tells my eyes to focus on the bright spots, and it makes it difficult for me to focus on other traffic. I for one, hope that LED tail lights remain a luxury good for quite a while to come ;)
    • by Sleepy (4551)

      Sure, you might see some applications "soldering" he LED right into the housing... just like it's done with some CPU & motherboard applications.

      If people want bulbs, though, they will get them. There's no monopoly on LED bulbs, and no builder conspiracy to require us to get non-servicable lights.

      The cost of manfacturing LEDs in a bulb fashion is cheap -- not much different than regular incandescents. The big holdup and cost is it takes too damn many bulbs to accomplish the lumens.

      You'll probably always

    • by jlanthripp (244362) on Sunday July 20, 2008 @03:19PM (#24264821) Journal

      Trucks use LED taillights because they are more visible in the daytime. It never ceases to amaze me how often a 4-wheeler (car driver) will rear-end a truck that is braking for a stoplight or turn, then claim that they didn't see the truck's brake lights.

      The LED taillights you see on a lot of semi-trailers are held in place by metal bezels that are riveted in place by the manufacturer. To replace one, you have to drill out the rivets. Then of course you can simply use self-tapping screws to put the bezel back on once you have replaced the light. Incandescents tend to be held in place by a rubber cup-like thing that I don't know the name for, and can be removed by prying on the light with a flathead screwdriver, much like dismounting a tubeless tire from a wheel.

      The reason for riveting the things in place is to deter theft. Incandescent lights don't get stolen nearly as often as LED's for some reason.

    • Re: (Score:3, Informative)

      by Anonymous Coward

      Take a hint from the car manufacturers. Today, high-end cars are using LED tail lights. They are also used on trucks. The main advantage is they do not burn out.

      However, for most people in the world a burned-out tail light bulb is a minor safety issue and a minor expense. Replacing the bulb takes 10 minutes and maybe the owner's manual if you are truely clueless about how to do it. Also, many people own a car for 5+ years without ever having to replace a single bulb.

      Compare this to the cost of a minor traffic accident where a tail light is cracked. No, you cannot replace the lens or any individual part, just the whole assembly. Instead of $100-$200 for an incandescent bulb assembly expect to pay $1500-$2000 for the LED tail light.

      Sure, over the life of many vehicles it is a minor issue that bulbs will never burn out. But over the same number of vehicles it is far, far more likely that a lamp assembly will have to be replaced. The result is a far more expensive part to replace.

      With trucks there is a certain amount of sense to be made with claiming that the bulbs do not have to be replaced. Replacing a bulb on a truck or semi-trailer can be a real hassle requiring a ladder and tools. However, again the likelyhood the bulb would ever need to be replaced vs. the lens being damaged is about the same as for cars. Basically, it is a complete rip-off.

      Expect to see wired-in LED systems in household lamps where the fixture must be replaced because the bulbs cannot be. Expect to see the fixtures sold to builders with non-replacable bulbs will cost the builder only slightly more when bought in huge quantities but the homeowner will be faced with $1000 lamp fixtures should they ever need or desire to replace them.

      I smell some FUD

      As for the replacement cost of a LED light component on a car. I personally can replace BOTH left and right sides of my cars LED light assemblies (which consists of 4 separate pieces) for $450. The leap from incandescent assemblies is only about $100. And yes, this is OEM, not a 3rd party solution. And to top this off, it takes about the same 10 minutes to replace these assemblies.

      As for it being a complete rip-off, the odds of it needing to be replaced is not the only implication. Most LED

    • I don't really expect to see any of these things. I've done some shopping today and see that you can ALREADY buy replacements for tail lights that screw into the same socket as the incandescent bulbs for far cheaper than your projected expected $1000+. Doing some very cursory googling, I see you can get a pair of really nice looking truck ones [gorecon.com] for $300. So that's $150 per tail light. You can also put "LED tail lights" into amazon and find plenty for $20-$50 a pair. That's the entire light, not just a s

    • by hardburn (141468)

      Car LED fixtures have huge margins. In fact, for the turn signals and brake lights, they should be dirt cheap since they're monochromatic.

      You can get white LED lights for incandescent fixtures right now for about $20 [theledlight.com]. CFLs are still probably more economical, but LEDs are catching up.

    • Re: (Score:3, Interesting)

      by smellsofbikes (890263)

      For what it's worth, one reason trucks have gone to LED's is that they don't die because of vibration, like incandescent bulbs do. We don't really know how long LED's will last, but if they're correctly designed, they should still have at least 50% brightness at 50,000 hours of operation.

      All the LED lighting solutions my company is building, and all the ones from our competitors that we've been buying and taking apart, are screw-in replacements for existing bulbs. Every single one, without an exception.

  • by LM741N (258038) on Sunday July 20, 2008 @02:52PM (#24264599)

    They really have a phobia about LEDs there- especially if there are wires attached like an AC cord.

  • by Animats (122034) on Sunday July 20, 2008 @02:53PM (#24264603) Homepage

    It's so Roland the Plogger.

    1. Find some minor advancement in materials science.
    2. Hype it as big breakthrough.
    3. Post on Slashdot.
    4. Direct traffic to ad-heavy blog.
    5. PROFIT!

    The "breakthrough" this time is that someone made gallium nitride substrates that might, someday, be useful for LEDs. After they solve the problem that their material cracks during cooling. However, Panasonic did that last year [compoundse...ductor.net], and has been shipping white LEDs using that approach in sample quantities.

  • I look forward to lighting my house with an incredibly piercing, harsh light. LEDs don't do soft, natural light very well
  • $100,00 - no way (Score:3, Insightful)

    by bvdbos (724595) on Sunday July 20, 2008 @02:58PM (#24264657)
    I don't know about the USA, but if LED-lights cost about $100,00 over there I'm going to set up an export-company. They're like E 10,00 in the Netherlands. Of course, with the current exchange-rates that could well be $500,00 tomorrow.
  • by Hektor_Troy (262592) on Sunday July 20, 2008 @02:58PM (#24264659)

    I realise it's customary not to RTFA, but I would think that the submitters would at least read what they submit. Roland wrote:

    It would also help to cut our electricity bill by about 10%

    The article says:

    a technology that could cut electricity consumption by 10 percent if widely adopted

    Far from the same thing. But I suppose that's another reason people don't like Roland.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      Far from the same thing. But I suppose that's another reason people don't like Roland.

      Wide adoption is a reasonable, implicit assumption when you're briefly summarizing the potential benefits of a new technology. Don't be such a pedantic whiner.

  • Do LEDs blink ? (Score:5, Interesting)

    by dargaud (518470) <slashdot2@nOsPAM.gdargaud.net> on Sunday July 20, 2008 @02:59PM (#24264663) Homepage
    Today for the first time I noticed a car with blinking tail lamps. When I say blinking, I mean it was blinking as fast as a CRT monitor, but the problem is that I can see it. I'm one of those people who has never been able to stand CRT monitors at less than 100 or 120Hz. I also have a hard time with some fluorescent lighting. I suspect what I saw was the lousy application of LEDs on the backside of a car.

    So, suck it up, I hear you say. Right, except that each blink leaves an annoying remanent patch on my retina that lasts for a few seconds. Imagine driving at night in a city, 10 cars in your field of vision, look left, right and suddenly you have 200 spots in your field of vision. Awesome to know what's going on, right ?

    I loathed the xenon high beams when they first came out a few years ago. You know, those tiny very concentrated blue lights ? Leaves a retina trail that lasts for 20 seconds. I'm so glad that they are gone now. I've never heard if they were made illegal or if they just went out of fashion, but I hope LEDs (which are a good technology) are applied in a good way...

    • Well, given that car electronics are powered by a battery (i.e. a DC source), it would actually require extra electronics to make the light blink. My best guess is that you saw a car with a short in one of the wires of the electric system.

      Note that in some LED applications, dimming is achieved by frequency modulation (i.e "blinking"). However, this is usually done at MUCH higher frequencies (several kHz), and I don't see why one would like to dim a car tail light.

      Light fixtures in homes are slightly more tr

      • Re: (Score:2, Informative)

        Actually, it is quite possible that dargaud saw frequency modulation. It is possible to over-power an LED but to pulse it such that the overall average is within the power limit. This is more of a guess on my part as I haven't played with overpowering LEDs much, but I would guess that the manufacturer had to power the LED so high (to get bright enough) that the frequency rate came within dargaud's visible range in order not to have the average power beyond the limit. I also wouldn't hold it to the maker

        • Re: (Score:3, Informative)

          by NormalVisual (565491)
          Odd about the dimming the light that way; IIRC the LEDs I've used can be extremely dim with low enough voltages without having to flicker it on/off.

          This is often true, but LEDs don't get brighter in a linear fashion when the input voltage (or current) is increased. Pulsing makes the perceived brightness much more controllable.
    • by funaho (42567)

      Are you referring to the effect where yuo see the light, look sharply left or right, and end up with a trail of dots in your visual field for a second or two? I get that a lot with brake lights these days.

      I first noticed it a few years ago with the aircraft warning lights on antenna masts; it's only been the past 2 years or so where I've started noticing it on car brake lights as well.

    • Re:Do LEDs blink ? (Score:4, Informative)

      by scorp1us (235526) on Sunday July 20, 2008 @04:28PM (#24265381) Journal

      Yes, the only way to vary the brightness reliably is to use PWM (Pulse width modulation, aka "duty cycle"). There is some variance from voltage, but the best way is to operate them at a constant voltage.

      All "breathing" LEDS (like on sleep mode for laptops) is accomplished this way. Duty cycle is controlled by a simple sin() or cos() function.

    • Re:Do LEDs blink ? (Score:5, Informative)

      by TaliesinWI (454205) on Sunday July 20, 2008 @06:12PM (#24266165) Journal

      I loathed the xenon high beams when they first came out a few years ago. You know, those tiny very concentrated blue lights ? Leaves a retina trail that lasts for 20 seconds. I'm so glad that they are gone now. I've never heard if they were made illegal or if they just went out of fashion [snip]

      Xenon HID headlights never went away. They're still standard equipment on higher end Japanese and some German luxury cars and optional on many others. If anything, their use by car manufacturers are expanding, not contracting.

      What YOU'RE complaining about, and thankfully seem to have gone away, are those high intensity blue color lights that dropped into a standard headlight assembly. Like you mention, I don't know if they were made illegal or became "uncool" but I hated them as well. True Xenon HIDs have a completely different reflector assembly than standard halogen headlights and spread the light far more evenly and are actually less annoying that a slightly misaimed halogen headlight, and you probably see them all the time and don't even realize it. They look "blue" only compared to what turns out to be the yellow tinge of a regular headlamp, but at a glance just appear very white.

    • Re:Do LEDs blink ? (Score:5, Interesting)

      by Chrontius (654879) on Sunday July 20, 2008 @08:38PM (#24267525)

      What you are seeing is the pulse-width-modulation dimming of the taillights applied with insufficiently high frequency. Cheap chinese flashlights like the Jetbeam C-LE (which has gone through three revisions prior to current - and is an absolutely excellent little LED torch) have been using increasingly high PWM frequencies to get around that; more expensive ones use current regulation (which averages the current of the PWM circuit over a few tenths of a second to produce a flat current (and therefore brightness) curve when viewed on an oscilloscope. The advantage of lower PWM frequencies is that the eye hands them off to the brain via a high-priority nerve link that results in people noticing them significantly (tenths of a second or so, IIRC) faster, theoretically reducing both the number and severity of accidents. The fact that many of them are bright enough to impair normal night vision seems to be lost on auto designers.

      HID headlights have not gone away, but their implementations have been getting better - projecting beams on a down-angle so they don't nail people in the eyes, lowering the operating temperature of the bulb, making them less blue and more yellow-white without making them dimmer (actually, lower-temperature HID bulbs are more efficient than the blue-tinted ones). HIDs are popular for bulb life being insane, since headlight replacement was getting to be a significant drain in carmaker's warranty claims, and being brighter and having a longer effective range, which is good when there's no streetlights.

      Entirely different is the blue-tinted halogen bulbs that are simply normal bulbs with a light blue paint applied - these are the ghetto-fabulous attempt to make it look like you've got an expensive HID conversion for an older car, and are about 30% dimmer than normal halogen headlights despite being harder on other drivers' eyes. I have no forgiveness for people who use these because they think it looks good.

  • Awesome. I wonder if these lights are powered by tabletop fusion [slashdot.org]?

  • many advantages (Score:4, Informative)

    by drfireman (101623) <.moc.grebmik. .ta. .nad.> on Sunday July 20, 2008 @03:08PM (#24264737) Homepage

    LED light bulbs are coming along. I've been keeping my eye on the GeoBulb sold by C Crane, but it's about $120 and always seems to be listed as out of stock. It is available in three color temperatures, however, so perhaps that's been worked out. There are a few others, including some T8 replacements. Unfortunately, they're all expensive and the ones that fit standard sockets max out at about the equivalent of a 60 watt incandescent. But these things will get worked out. On the plus side, advantages include not just electrical savings and longevity, but also less heat (less risk of fire) and less vulnerability to things like vibration and moderate temperature changes. Unlike compact fluorescents, they contain no mercury and turn on/off instantly. I believe some are dimmable, but I'm not sure. In any case, it seems clear that it will only take a few years of fairly routine development for LED bulbs to be much more practical than all the alternatives. There doesn't seem to be a down side.

    The summary would seem to imply only modest electrical savings. I'm pretty sure the 10% figure just reflects the fact that light bulbs are only part of your electrical picture. The rated wattage for a 60-watt equivalent is about 8 watts. Correcting for overoptimism, that's about 80% savings wherever you plug one of these in.

  • I've looked into LED lighting in the past and if it weren't so expensive I would have given some of these lights a try. So I look forward to the technology being more affordable.

    However, a concern I have with LEDs is that the light is always too focused, even those that are supposedly less directional. This, in my opinion, makes them impractical to be used in the home. The light certainly is bright, but it's useless if it's casting only a narrow beam of light.

    Perhaps reflective enclosures will address that

    • by tftp (111690) on Sunday July 20, 2008 @03:32PM (#24264929) Homepage

      Can LED's be dimmed? As far as I've seen it's not possible.

      Not so. LEDs can be dimmed either by regulating the forward DC current (then they don't flicker at all) or by pulse-modulating some fixed current; the LEDs in the latter case will flicker only if the frequency of the pulses is too low. LEDs have very low capacitance and inductance, so they can be easily pulsed with any high frequency of your choice, though 1 kHz would be more than enough. And as I said the DC source works also.

      • Re: (Score:3, Interesting)

        by Mr. Flibble (12943)

        Dimming LED's.

        LED's are commonly dimmed in headlamps. I have right next to me a Petzel Tikka XP Headlamp that has multiple LED light settings. And yes, each of those settings is a different dim setting. The LED can also be "over-driven" for a short period, putting out more light than normal.

        So, parent poster is correct, LED's do dim, and they dim quite well.

    • Well, it could be possible to make LED bulbs out of a matrix of LEDs, and then have a controller which can turn off individual LEDs. Homemade LED ambient lighting systems already do this. You get a nice array of red blue and green LEDs, and using a controller you can change the colours being thrown on the wall. Cool stuff. However, I have a feeling that we may end up heading towards single element bulbs.
  • There is a company working on a replacement righting technology. It is 2x as efficient than LED, and has a much better frequency profile that matches natural light.

    It is a capsule of gas, which is surrounded by a oscillating field. This field causes the gas to emit photons. (My dad used to have a neon capsule that you could put next to a AC current and see if there was current flowing - same principle)

    LED is on its way out already.

  • only 10%?

    I replaced all the bulbs in my house with CFL, and I like my lights bright.

    75 watt bulbs were replaced with 25 watt.. .

    that's a cut in electricity use of 66% with CFL's.

  • I'm as much of a tree-hugger as the next guy, but I really don't like Compact Flourescent bulbs. Theoretically, if you're worried about energy use, they're a good idea. But I think in practically, they're a bad idea, because of the mercury content.

    Compact fluorescents give out crappy light, and nobody really wants crappy light in their home. It's the wrong color, wrong intensity, etc. Once LEDs become widely available, we'll all be throwing out the compacts, and replacing them with LEDs that give off ligh
  • by rickkas7 (983760) on Sunday July 20, 2008 @03:59PM (#24265175)
    LED lighting is already cost effective in certain situations. I priced a cable-hung low-voltage lighting system using LED-based MR-16 socket bulbs vs. 12 volt halogen incandescent and the system pays back in less than a year in electricity savings. That doesn't even count the significantly smaller number of bulb changes that are required.

    If you have a large number of low wattage/low voltage light sources, CFL is not viable, but LED is. The power requirements are so much lower that smaller transformers can be spec'd, you can string piles more of them on a circuit, saving even more money.

    There are some neat bulbs available at http://www.theledlight.com [theledlight.com].
  • I'm getting some SMD bulbs which produce very nice quality light. Normal LEDs are packaged to intentionally direct the beam, as this has generally been desirable for most applications so far. But this isn't necessary.

    LEDs don't inherently produce highly directed light, and hopefully we will see more of these SMD bulbs in future.

    Here's the one I've got - it's a spotlight bulb because that's what the light fitting takes, but there are standard bulbs also available.

    http://www.globalgreen.co.uk/led1.php [globalgreen.co.uk]

  • by Maxo-Texas (864189) on Sunday July 20, 2008 @05:36PM (#24265877)

    Very dim. About 50% of the amount of light they advertised to put out.

    Even adding a lot of these wouldn't increase the light above "dismal" level-- the intensity of the light was just lower than that put out by CFL and incandescent.

    I want LED to work-- they last a long time, they use no power, and they have no mercury.

    These might be okay for a porch light-- dim but always on.

  • by LM741N (258038) on Sunday July 20, 2008 @05:50PM (#24265973)

    because they aren't going to exist much longer into the future. http://www.idtechex.com/products/en/articles/00000591.asp [idtechex.com]

    I also find it ironic that everyone seems to love that mercury is not contained in LED's, yet is it essential to the extraction of gallium from ore.

  • $100 to $5? (Score:3, Insightful)

    by Flentil (765056) on Sunday July 20, 2008 @06:07PM (#24266131) Homepage
    According to the blurb, current LED bulbs sell for $100 and they expect this new breakthrough to lower the cost to $5. I can see that being possible for the manufacturing cost, but the cost to the consumer will always be set to one click below 'haha yeah right'. It's the way of business. Look at how many times in the past couple years we've been told that the cost to manufacture solar panels will be cut in half. You'd think with all that progress we'd be able to roof a house with them for about $10, when actually the cost remains one click below 'are you insane?' as always.

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