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Making Strides Toward Low-Cost LED Lighting

timothy posted more than 6 years ago | from the brightly-walk-among-the-clouds dept.

Power 398

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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Yea, (1)

jsmiith (1274436) | more than 6 years ago | (#24264441)

But how much of an improvement will they be over fluorescent lights, which we already have at an affordable price?

Re:Yea, (4, Informative)

Anonymous Coward | more than 6 years ago | (#24264469)

They will be way more environmentally friendly. No mercury involved.

Re:Yea, (1, Informative)

NFN_NLN (633283) | more than 6 years ago | (#24264477)

But how much of an improvement will they be over fluorescent lights, which we already have at an affordable price?

Less mercury.

Re:Yea, (3, Informative)

nhtshot (198470) | more than 6 years ago | (#24264483)

No mercury = huge improvement

Re:Yea, (4, Informative)

pushing-robot (1037830) | more than 6 years ago | (#24264509)

But how much of an improvement will they be over fluorescent lights, which we already have at an affordable price?

Well, they won't flicker, they won't contain mercury, and they won't be too big to fit in many light fixtures.

Even if LEDs aren't any more efficient than current CFLs, they'll be a lot more attractive to people who don't like or can't use fluorescent lights.

Re:Yea, (5, Informative)

sdpuppy (898535) | more than 6 years ago | (#24264699)

Also, TFA states that LEDs have the potential to well surpass fluorescent bulbs in terms of energy efficiency.

Another article http://pubs.acs.org/isubscribe/journals/cen/86/i28/html/8628cover4.html [acs.org] provides some interesting information on organic LEDs - OLEDs have interesting design applications since you can make them in flat sheets

(I think an illuminating wall would be way cool, but maybe thats just me :-))

Right now efficiencies are similar to the inorganic LEDs and fluorescent bulbs.

Re:Yea, (5, Interesting)

kaizokuace (1082079) | more than 6 years ago | (#24264901)

not just an illuminating wall. Imagine the entire ceiling covered in an OLED sheet and have lighting do cool stuff like follow you around or whatever. Rooms with people get lit while others don't. Crazy flashy lights for parties. the possibilities are limitless!

Re:Yea, (5, Informative)

SeaFox (739806) | more than 6 years ago | (#24264777)

Well, they won't flicker, they won't contain mercury, and they won't be too big to fit in many light fixtures.

2003 called, it wants it's CFL stereotypes back.

CFLs don't flicker like old ballast-type fluorescent tubes of decades ago. And the newer ultra-compact ones are actually smaller than the incandescent bulbs they replace. I have one in the swing-arm desk lamp in front of me right now, and the tip of the bulb no longer protrudes past the end of the shade like the old bulbs I used in it long ago. In my bathroom I have CFL bulbs made to look identical to G25 globe lights, in the same fixture with the actual incandescent bulb I am slowly replacing. They appear the same except the CFLs are brighter and their light isn't as yellow.

I will give you the mercury, though.

Re:Yea, (4, Informative)

A beautiful mind (821714) | more than 6 years ago | (#24264997)

The mercury depends on efficiency aswell. Modern CFLs have <=2mg mercury content, (at least the CFLs I own). Over a 5 year period, the electricity needed for CFLs, generated by coal based power plants in some portion, releases 2.4mg of mercury into the air. For incandescents the number is 10mg over a 5 year period. LED lighting is currently less efficient than CFL, so more mercury gets into the air.

The question is really, whether you prefer 2.4mg of mercury in air plus 2mg in the landfills, or more than 2.4mg of mercury in the air. Until LEDs become more efficient than CFLs, I'll opt for CFLs.

Note, there is a confusion over LED vs CFL efficiency. LEDs generate light more efficiently than CFLs, but they do so in a narrow arc. To make it useful for everday applications conversion to a wider arc takes place and that causes efficiency loss.

Re:Yea, (1)

Hatta (162192) | more than 6 years ago | (#24265027)

No, they don't flicker any more but they still look like crap. I'm sitting under one right now, and it wouldn't be tolerable if I didn't have an incandescent right next to it. I prefer the warm yellow tinge of incandescents to the cold blue hue of CFLs.

CFL Color (5, Interesting)

wooferhound (546132) | more than 6 years ago | (#24265261)

you need to look at the Color Temperature when you buy CFL bulbs. A CFL rated at 2700 degrees Color Temperature will look almost exactly like an incandescent light. A CT of 3000 degrees is called a warm white and is very pleasing. A CT of 4000 is called a cool white and looks a little bit blue. And a CT of 5000 degrees or more is about the same color as Sunlight and appears to be very blue indoors.

I really like the color you get when a 2700 & 5000 degree light are in the same fixture, everything looks bright and colorful.

Re:CFL Color (1)

Hatta (162192) | more than 6 years ago | (#24265285)

Sunlight is slightly yellow, so why does a daylight CFL look blue?

Re:Yea, (1)

parens (632808) | more than 6 years ago | (#24265065)

If I might inquire - where do you find these smaller CFLs ? Every CF i've seen retail for years now has been some crappy generic brand with a giant ballast and protruding bulb tips, not to mention they still burn out just as often as incandescents. I'd love to switch my home over to CFLs, but every time i've tried to, I either have size problems, color temperature problems, audible buzzing, and/or burnouts.

Re:Yea, (1)

Translation Error (1176675) | more than 6 years ago | (#24265299)

I will give you the mercury, though.

No, thank you.

Re:Yea, (4, Insightful)

Aaron B Lingwood (1288412) | more than 6 years ago | (#24265319)

>2003 called, it wants it's CFL stereotypes back.

>CFLs don't flicker...

CFLs cause me migraines and other visual problems. I recently changed all my home lighting, where possible, to CFLs.

After a week, I began suffering from an extreme migraine. As the CFL's made it difficult for me to read or focus on small objects - I instantly held them suspect. To test my theory, I changed all the lighting back, and by the next day my life had certainly improved.

I gave it a month and tried the CFL's again, and again after a week a migraine set in. I intend to remove them tomorrow. My girlfriend (as in a living 3D female human-being [facebook.com] ) who doesn't normally suffer from migraines has been complaining of symptoms while I had the CFLs in.

I think CFLs definitely have a use but not as a be all and end all of general home lighting. The most pleasant affordable technology for me is halogen lighting. I am looking forward to what LED and OLED technology has to offer in the near future.

--
Deceive the rich and powerful if you will, but don't insult them.

Re:Yea, (1)

wooferhound (546132) | more than 6 years ago | (#24265169)

The article says that the LED lighting is equaling the efficiency of Fluorescent lighting, But if you look around for LED Efficiency you will find that LED lights are very much less efficient than Florescent lights. I believe they were more talking about a cheaper way to make LED lighting, but it's not any more efficient.

Re:Yea, (4, Informative)

A nonymous Coward (7548) | more than 6 years ago | (#24264569)

In addition the no mercuary as already noted, they will have a longer life, be less fragile, and be smaller.

Re:Yea, (0)

Anonymous Coward | more than 6 years ago | (#24264639)

1> They last longer
2> They cost less to use

Add up the savings through these two points and the inevitable conclusion must be that some researchers at Purdue University (or the people financing them) look set to make a fortune.

Re:Yea, (0)

Anonymous Coward | more than 6 years ago | (#24264653)

Let's not forget improved cold weather characteristics

Re:Yea, (3, Interesting)

tomhudson (43916) | more than 6 years ago | (#24264761)

Poster saith:

Let's not forget improved cold weather characteristics

TFA saith:

"You all know that incandescent bulbs are pretty inefficient, converting only 10% of electricity into light and 90% into heat

Me: "I live in Canuckistanbul - we NEED the heat, you ignorant clods!"

Electricity costs less than oil or gas here ... it's cheaper to get some extra BTUs from incandescents in the winter months ...

Re:Yea, (1)

zOper (1329465) | more than 6 years ago | (#24265335)

I prefer heating my rooms with computers and plasma/LCD panels. ;)

Re:Yea, (0)

Anonymous Coward | more than 6 years ago | (#24264841)

But how much of an improvement will they be over fluorescent lights, which we already have at an affordable price?

The efficiency of Fluorescent lamps is about 22% (compared with 10% of incandescents.) LEDs are over twice as efficient as Fluorescent bulbs. They also last much, much longer.

I have a few LED led bulbs installed around my apartment (equivalent to a 30 watt bulb) and they are too "cool" for me to consider using them as my only lighting. The sun produces 100% on the "Color Rendering Index" scale. Incandescents produce about 80% CRI. LEDs are still only at about 70% CRI.

Re:Yea, (2, Informative)

funaho (42567) | more than 6 years ago | (#24264897)

They'll also have a longer lifetime than CFLs. The article says they could last as long as 15 years, compared to CFLs which I believe have an expected life of about 7 years.

Is it white, though? (1)

neokushan (932374) | more than 6 years ago | (#24264475)

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?

Re:Is it white, though? (0)

Anonymous Coward | more than 6 years ago | (#24264531)

Why do you gotta be so racist against the blues!? Sheesh, white this white that. Sounds like you think white is superior in every way.

Re:Is it white, though? (-1, Troll)

wiIIyhilI (1329451) | more than 6 years ago | (#24264535)

No because it is politically incorrect to do so, thanks to the liberal Jews who give too much power to the niggers.

LED lights should be as close as to the nigger color as possible.

Your lack of intelligence is shining brightly (0, Offtopic)

A nonymous Coward (7548) | more than 6 years ago | (#24264601)

Dipshit. You could have come up with all sorts of bigoted Asian jokes since sunlight is not white but yellow. Instead you spew about Jews and blacks. Heck, even a joke about uv light would have been more interesting.

You are pathetic and have no imagination.

Re:Is it white, though? (1)

joaommp (685612) | more than 6 years ago | (#24264541)

there are LED "light bulbs" based on sets of same amount of blue, green and red LEDs packed together. Those aren't a shade of light blue and some of them can actually be "tunned" to a desired color/tone for whatever purpose.

Re:Is it white, though? (1, Informative)

Anonymous Coward | more than 6 years ago | (#24264745)

Those are not really white. They only produce the sensation of white when you look directly at them or when they illuminate surfaces which evenly reflect the red, green and blue light of these LEDs.

People are so used to TV screens and computer monitors using RGB to create "all" colors that they think every light can be produced as a combination of red, green and blue. That is not the case. Most of the things that we look at are not light emitters. Reflected light however depends on the spectrum of incident light and the reflectance spectrum of the surface. You can shine RGB-white on a yellow surface and have it appear black, because the wavelength of yellow light which the surface reflects is not in the RGB white. Then the surface absorbs the red, green and blue light and appears black. That's why your mom told you to buy clothes only after you've seen them in daylight, because artificial light doesn't have the spectrum for exact color matching. Those pants which you thought were black may actually be a dark blue and not match your black jacket. Pay attention to your physics teacher and/or your mom.

Re:Is it white, though? (5, Informative)

TheLink (130905) | more than 6 years ago | (#24264565)

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:Is it white, though? (2, Interesting)

sdpuppy (898535) | more than 6 years ago | (#24264783)

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 close (and besides the frequency that an LED produces does have a band width, so if each color is close enough, you do get a continuum with enough colors.)

Anyone know if anyone is working on either method?

Re:Is it white, though? (4, Informative)

De Lemming (227104) | more than 6 years ago | (#24265161)

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] .

Re:Is it white, though? (1)

that IT girl (864406) | more than 6 years ago | (#24264635)

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:Is it white, though? (2, Informative)

gardyloo (512791) | more than 6 years ago | (#24264687)

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.

Re:Is it white, though? (1)

Martin Blank (154261) | more than 6 years ago | (#24264981)

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.

Re:Is it white, though? (1)

that IT girl (864406) | more than 6 years ago | (#24265075)

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 only variable is the lighting.

Re:Is it white, though? (1)

nmg196 (184961) | more than 6 years ago | (#24265281)

> 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.

Re:Is it white, though? (1)

funaho (42567) | more than 6 years ago | (#24265097)

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.

Re:Is it white, though? (1)

shmlco (594907) | more than 6 years ago | (#24265243)

"... 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....

Re:Is it white, though? (1)

Arterion (941661) | more than 6 years ago | (#24265263)

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 the truth.

What you ARE seeing as the problem is the difference between full-spectrum lighting and light that has a low CRI (Color rendering index). There's no clearly visible difference (as with color) between low CRI and high CRI (full spectrum) lighting, except that one causes your vision to feel strained.

Do yourself a huge favor and go to store that specialized in lighting, and find yourself a true full-spectrum CFL, and give it an honest try. The stuff they sell in supermarkets sucks, and I won't use them either. I would suggest a light about 5000K, because anything higher -- though it is truly more like natural sunlight -- will appear really, really blue when you compare it to the other light you'll see at night.

Re:Is it white, though? (0)

Anonymous Coward | more than 6 years ago | (#24264833)

Guys, are you aware that they have white LED's? Check www.whiteled.net

This seems to be a change in the way that LED's are manufactured so as to make them more affordable, not to change the colors.

We use some white LED's at work, and they are very weak unless there are a lot of them in a bulb. How efficient are they when you have to use 100 of them to create the light of one 60w CFL is my question.

If anybody can point me to a good white light CFL that actually has a payback under 1 year, it would be appreciated.

carbon-free daytime lighting (0)

Anonymous Coward | more than 6 years ago | (#24264517)

With the cost of solar cells and LEDs plummeting, a solar cell roof installation with closed-circuit LEDs might soon become cheaper than a ceiling window.

Re:carbon-free daytime lighting (3, Funny)

4D6963 (933028) | more than 6 years ago | (#24264557)

With the cost of solar cells and LEDs plummeting, a solar cell roof installation with closed-circuit LEDs might soon become cheaper than a ceiling window.

What do you know! Soon enough it'll all get so efficient that with closed-circuit LEDs shining on solar cells you'll be able to make your own infinite source of energy!!

Oh shit that's a hell of good idea! The first one to the patent office wins!!

Re:carbon-free daytime lighting (0)

Anonymous Coward | more than 6 years ago | (#24265331)

You do know it costs a huge heap of cash to cut a whole out of your roof and install a piece of glass, right?

I heard (-1, Troll)

Anonymous Coward | more than 6 years ago | (#24264519)

That Roland enjoys fellating men.

Re:I heard (0)

Anonymous Coward | more than 6 years ago | (#24264543)

That Roland enjoys fellating men.

Only Timothy.

Light vs. heat scale (3, Interesting)

WhoIsThePumaman (1182087) | more than 6 years ago | (#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?

THANK GOD (-1, Troll)

wiIIyhilI (1329451) | more than 6 years ago | (#24264555)

Today, while driving through town, I wound up behind a minivan that had a big sticker on the back. The sticker had an Israeli flag in the middle of it, and under it the quotation from the book of Genesis that reads âoeI will bless those who bless thee.â

I would like to take this time to list my own reasons for thanking and blessing Israel, our lone ally in the Middle East, for everything she has done for us, since I am quite sure most Americans are unaware of just what kind of friend she has been to us.

For extorting from me and my fellow Americans $4,000,000,000.00 a year for the last 4 decades, we bless thee.

For taking our most sophisticated weapons technology and stealing it for yourself without paying the American patent holders, we bless thee.

For taking that high-tech military technology and selling it to our enemies, such as the Russians and Chinese, thus further endangering us, we bless thee.

For using that weaponry in a sustained attack against a United States ship, the USS Liberty, in an attempt to sink her, thus preventing US servicemen from revealing to the rest of the world information concerning the war crimes they witnessed you commit against Egyptian soldiers in the Sinai Desert during the Six Day War, as well as for the purposes of dragging the US into yet another one of your murderous adventures, we bless thee.

For killing 35 and wounding 170 American sailors aboard the USS Liberty, we bless thee.

For bribing the United States government into covering it up, preventing any justice from being done for the benefit of the families of the lost sailors - as well as the American People, we bless thee.

For sending your agents into Egypt and blowing up American buildings for the purpose of blaming the Arabs in an event known as the Lavon Affair, we bless thee.

For sending your agents into Libya during the Reagan administration, and broadcasting radio messages in Arabic that were designed to sound like âoeterrorist cell planningâ so that the US would initiate military strikes against Khadafi in an event known as Operation Trojan Horse, we bless thee.

For withholding information from us concerning the planned attacks against the US Marine barracks in Lebanon, attacks you knew about through your moles in the Islamic world and about which you deliberately refused to warn us in order to further your interests against the Arabs, we bless thee.

For employing Jonathon Pollard, an American serviceman paid to spy for Israel in order to steal even more of our National Security secrets for your parasitic purposes, we bless thee.

For blackmailing President Clinton through one of your sayanim, Monica Lewinsky, in order to prevent a coherent peace program from being pushed forward between yourself and the Palestinian people whom you have brutalized and murdered for the last 50 years, we bless thee.

For breaking every agreement you have made with your Arab neighbors, stealing their land, displacing, murdering, and treating them like the animals you see them as, we bless thee.

For using your agents within the first Bush administration to involve us in the first Gulf War, causing the deaths of American men and women, and exposing our servicemen to whatever bioweapons were and are responsible which have led to Gulf War Syndrome, we bless thee.

For your role in the September 11 attacks in this country, and for blackmailing and bribing the US government into deporting back to Israel the 100 or more intelligence agents that were arrested after the attacks, we bless thee.

For suppressing the information from the American people of your involvement in the September 11 attacks and sending us in the wrong direction in search of answers, we bless thee.

For using one of your agents in the US Army Weapons Lab to steal anthrax and distribute it into our mail system, terrorizing US citizens and killing several in order to blame the Arabs, we bless thee.

For using your agents in the US Government, namely, Rumsfeld, Wolfowitz, Perle, Abrams, and the rest into initiating this war in the Middle East so that you could bring to heel all the enemies you have made during the last 50 years, we bless thee.

For using your agents in the media to lie to us on a minute by minute basis about the war, lying to us as to how âoejustâ this cause is, and what the real reasons behind it are, we bless thee.

For using your agents in the Christian Evangelical community, such as Falwell, Graham, Swaggert, Robertson and the rest who praise you as Godâ(TM)s chosen people and further keep Americans in the dark about who you really are what you have done, and what you are truly about, we bless thee.

For bringing idiots like Limbaugh, Liddy, Hannity, Beck, Oâ(TM)Reilly and Savage to the forefront as paid liars who will support you and further lead Americans astray, we bless thee.

For making America your attack dog, and for sending her sons and daughters to fight and die in all your future wars, we bless thee.

For using your influence in the media to hide the real statistics about the war, the dead and wounded on both sides, we bless thee.

For using us in such a way that not only further inflames the Arab world against us, but as well has succeeded in our alienating ourselves against those nations with whom we have been friendly for over a century, we bless thee.

And finally, for using your influence in our media and academia to flood our minds with pornography and lies, as well as inculcating in us a hatred for our history, religion, and culture, for dividing our nation between races and sexes, and for releasing into our society all of your plagues and filth that have left us a rotted out corpse of a once great nation, oh Israel, our friend,

we bless thee.

Re:THANK GOD (0)

Anonymous Coward | more than 6 years ago | (#24264861)

At least the jews don't want my girlfriend to wear a rag on her goddamn head.

LED = Luxury Goods (5, Interesting)

cdrguru (88047) | more than 6 years ago | (#24264563)

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.

Re:LED = Luxury Goods (1)

failedlogic (627314) | more than 6 years ago | (#24264701)

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:LED = Luxury Goods (2, Interesting)

ModernGeek (601932) | more than 6 years ago | (#24264727)

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:LED = Luxury Goods (1)

Sleepy (4551) | more than 6 years ago | (#24264807)

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 need more than 1 LED to make a bulb, simply because the LEDs are very 'directional' instead of 'point' lights. But today's LEDs are weak and expensive, so instead of getting by with say 8 LEDs, you need like 50-100 for a omnidirectional light.

I have a few of these in spotlight form. The $8 20 LED ones make great desk and reading lamps (or killer nightlights if you want to keep another room lit at night). The ones that compare to regular bulbs are $35-$100 and at that price, I'm not willing to get one even as a test.

Another technology to watch is CCFL -- Compact Cold Fluorescent Lighting. Right now it's mostly used in PC cases by the LAN party kids, but it's starting to be used in bulbs.

Re:LED = Luxury Goods (2, Insightful)

sdpuppy (898535) | more than 6 years ago | (#24264911)

Solution - make the LEDs as an array/matrix on a chip, similar to the way CPUS are made now. A million or so LEDs glowing should be fairly bright.

Re:LED = Luxury Goods (4, Informative)

jlanthripp (244362) | more than 6 years ago | (#24264821)

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:LED = Luxury Goods (1)

sdpuppy (898535) | more than 6 years ago | (#24264879)

Interesting post, and I don't doubt that built-in fixtures will be produced.

Now for cars, don't forget that it is assumed that people who buy the high end cars don't care about paying extra $$ to get their car repaired (true or not) - and whether it costs significantly more to change a high end light (well it is so much more highly styled)

If you do care about costs, and don't own a fancy smancy car, you can still reap the benefits of LED signals.
A visit to a local Pep Boys store shows that you can buy a standard incandescent turn signal bulb or a new fangled LED turn signal bulb which fits in the same socket.
So the rich or style-conscious will buy the expensive to maintain stuff and the rest of the grunts will buy the utilitarian LED bulbs that screw/bayonet into standard fixtures.

Re:LED = Luxury Goods (3, Informative)

Anonymous Coward | more than 6 years ago | (#24264887)

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 components on cars that I know of are more visible, take lest time to be "on." Additionally, they draw less current thus putting less strain on the power generation and results in a slight efficiency and MPG boost.

From a build-out perspective you can even use smaller, more compact alternators that don't need to put out as much energy to run conventional lighting. I don't know much about the LED's manufacturing process but suspect you get a smaller carbon footprint there too as you don't need to melt a bunch of glass to make bulbs with... etc.

Even tho I am not a tree-hugging sprout-munching environmentalist, I can see the bigger picture with LED lighting.

Supporting evidence? (1)

illegalcortex (1007791) | more than 6 years ago | (#24264907)

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 single bulb.

The only place I can see it costing significantly more is for luxury cars like BMW/Lexus/etc. And that's only because everything always cost a premium on those cars.

Your expectations of home builders seem equally implausible. Do you even realize how often the home builder themselves would accidentally break the lights? They're not going to buy products that cost them $1000 when someone slips up and hits the bulb with a hammer. Equally unlikely is the success of any light fixture with a non-replaceable bulb sold directly to consumers. One of the first things they'll notice is that they can't replace the bulb. They'll either not buy it in the first place, or take it back and get a refund.

All in all, I just find your expectations to conflict with what I know of reality.

Re:LED = Luxury Goods (1)

hardburn (141468) | more than 6 years ago | (#24264917)

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:LED = Luxury Goods (0)

Anonymous Coward | more than 6 years ago | (#24264945)

I bigger gain is that LED tail lights light up faster then incandescent ones. The sooner the guy behind you starts stopping the better chance you have to avoid the accident.

Re:LED = Luxury Goods^H^H^H directional and color (1)

claykarmel (78187) | more than 6 years ago | (#24265011)

I don't think so.

Trucks and cars use LED lighting for the same reasons that traffic lights do. They are already colored and directional.

Low heat, low power dissipation and high shock/vibration tolerance are also pluses.

LED home lighting can avoid the CFL problem of being 'too white', and may first appear as architectural lighting (where intensity and color are varied by time of day, event or spacially).

I know I'd pay more for a LED solution that wasn't 'cold white', rather than install florescent in my kitchen or bathroom. Building codes now require florescent in those rooms, so look there for early adoption in new homes (when the present housing crisis abates).

Re:LED = Luxury Goods (0)

Anonymous Coward | more than 6 years ago | (#24265063)

I've had to replace a couple of bulbs in my car. Each time I had to remove the bulb, drive to the store, drive home, replace the bulb. Factor in my time, fuel, and the cost of the bulb, and it's not quite as cheep as you make it out to be. Factor in ALL of the people around the world that have to do exactly the same thing and you'll see it adds up rather quickly. Also, you argument about fixtures costing $1000 is pretty out there too.

Re:LED = Luxury Goods (1)

BlueFireIce (1014121) | more than 6 years ago | (#24265083)

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.

LED tail lights are far from the $1500 range. Just look at all the aftermarket tail light kits out there, allot of them are even cheaper than OEM replacements. And in most tail light set ups you CAN just replace the lens housing, as the bulbs twist in. And many LED tail lights are going the same route to where they can be more readily replaced.

The only time you are going to see a 1500+ price on a light is on high end cars such as Mercedes, we had one in the shop just a few weeks ago and the headlights ran 1200 each (and that's shop cost). Luxury car tail lights don't cost allot because of the LED's in them but because they are high end cars and the owners can afford to shell out the money for it.

Re:LED = Luxury Goods (0)

Anonymous Coward | more than 6 years ago | (#24265199)

The other reason LEDs are used in taillights is because the reach full brightness a lot faster. If I remember correctly, it means the driver behind you would come to a stop about 5 feet sooner at 30 MPH. That could mean the difference of whether you have to peel a Ford Focus off your bumper.

Don't market these in Boston (3, Funny)

LM741N (258038) | more than 6 years ago | (#24264599)

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

It's Roland the Plogger, wrong as usual (4, Interesting)

Animats (122034) | more than 6 years ago | (#24264603)

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.

Re:It's Roland the Plogger, wrong as usual (1, Informative)

Anonymous Coward | more than 6 years ago | (#24264703)

The article you link is about growing on a GaN substrate, not Si as the Purdue team is doing.
Growing on GaN is probably even better (the substrate is the same material as what you're growing), the trick has always been being able to grow large amounts of GaN in a time and cost-effective way.

The Purdue work is interesting, but they're downplaying some significant hurdles. They note that using silicon allows for much larger substrates (Si substrates are now reaching 450 mm, Saphire is just making 100 mm), but the stain problems (such as cracking when cooling) are just worse when you go to larger substrates.

Re:It's Roland the Plogger, wrong as usual (0)

Anonymous Coward | more than 6 years ago | (#24264751)

  • Direct traffic to ad-heavy blog.
  • PROFIT!

Good theory. Except, TFA is on Purdue.edu, not a blog...

Re:It's Roland the Plogger, wrong as usual (5, Insightful)

nasor (690345) | more than 6 years ago | (#24264995)

Uh...the linked article is on a purdue.edu page and has zero adds. Am I missing something?

Re:It's Roland the Plogger, wrong as usual (3, Informative)

Anonymous Coward | more than 6 years ago | (#24265277)

You're missing the "Roland Piquepaille" link just on top of the summary.

More efficient than fluorescents lights? Really? (0)

Anonymous Coward | more than 6 years ago | (#24264613)

About two years ago I worked with someone who was in the LED industry, and when I said something similar (that LEDs produced light more efficiently than fluorescent bulbs) he stopped me and said that that was a popular misconception, or at least a statement that didn't tell the whole story. He later pointed me to a table showing various luminous efficacies at Wikipedia [wikipedia.org] .

It turned out to be yet another experience where I'd heard something so many times -- something that just sounded right -- that I'd accepted it as being true. Kind of like the myth that flash memory's limited number of write cycles is something to worry about in real-world scenarios (it isn't).

At least the flash memory myth is dying though. It seems the majority of people are still championing LEDs as being at the top of the list of efficient light producers. Well they're not there yet, and for some lighting needs they'll likely never be.

LED lighting (1)

abigsmurf (919188) | more than 6 years ago | (#24264641)

I look forward to lighting my house with an incredibly piercing, harsh light. LEDs don't do soft, natural light very well

Re:LED lighting (0)

Anonymous Coward | more than 6 years ago | (#24264747)

I look forward to lighting my house with an incredibly piercing, harsh light. LEDs don't do soft, natural light very well

Well if you think the other alternative, compact flourescents do, you are on drugs. I don't care what anyone else says.

$100,00 - no way (2, Insightful)

bvdbos (724595) | more than 6 years ago | (#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.

Re:$100,00 - no way (0)

Anonymous Coward | more than 6 years ago | (#24264885)

To be clear--$100 is the price point for current generation LED "lightbulb replacement" lamps. Most of these are lightbulb-shaped collections of many LED's, which screw into standard sockets and produce roughly similar light output to a "standard" lightbulb.

The price of the individual white LED's is of course substantially smaller.

Re:$100,00 - no way (1)

bvdbos (724595) | more than 6 years ago | (#24265045)

Yep, I have those in my home for this price (E10.00). Got them at the local shopping mall... Perhaps the presence of Philips in the Netherlands makes them cheaper over here?

Re:$100,00 - no way (0)

Anonymous Coward | more than 6 years ago | (#24264963)

I think we're talking about two different LED lights. We have some that are roughly â15, See here [homedepot.com] but those are not a true replacement. The $100 ones are these ones [ccrane.com] that provide a much better lighting. If you have ones in the Neatherlands like that for â10, post a link. A few of us in the US would like to see that.

Re:$100,00 - no way (1)

bvdbos (724595) | more than 6 years ago | (#24265107)

I'm in no way connected to this store but these are the newest LED-bulbs from Philips: just one shop: modern.nl [modern.nl] . I do have some connections with Philips so I can keep up with development.

Re:$100,00 - no way (1)

bvdbos (724595) | more than 6 years ago | (#24265123)

of course, since this is Philips, the lights are rather expensive. There are cheaper brands with less quality. The intensity decreases much faster and there's paler colors.

Electricity savings ? (4, Informative)

Hektor_Troy (262592) | more than 6 years ago | (#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:Electricity savings ? (2, Informative)

Anonymous Coward | more than 6 years ago | (#24264959)

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 ? (5, Interesting)

dargaud (518470) | more than 6 years ago | (#24264663)

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...

Re:Do LEDs blink ? (0)

Anonymous Coward | more than 6 years ago | (#24264913)

Short answer:

No.

Longer answer:

LEDs have a near instantaneous on-off time, in contrast with incandescents (which take a little while to warm up to/cool down from visible temperature--longer than the 60Hz cycle time on your household circuit). If you supply an LED with non-continuous current, it's going to flicker at the same rate as the current.

Re:Do LEDs blink ? (1)

eggnoglatte (1047660) | more than 6 years ago | (#24265059)

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 tricky, because the power source is AC. You need an inverter and a small capacitator to suppress flicker, but that is pretty straightforward and inexpensive stuff, so there is really no reason why an LED bub should not contain these.

Re:Do LEDs blink ? (2, Informative)

Destined Soul (1240672) | more than 6 years ago | (#24265213)

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 to presume that anything above 60Hz is fine.

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.

Re:Do LEDs blink ? (1)

funaho (42567) | more than 6 years ago | (#24265171)

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.

Purdue University researchers? (1)

Fear the Clam (230933) | more than 6 years ago | (#24264717)

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

many advantages (3, Informative)

drfireman (101623) | more than 6 years ago | (#24264737)

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.

Concerns about LEDs... (1)

MaWeiTao (908546) | more than 6 years ago | (#24264825)

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 issue. I suppose someone could cover an entire ceiling in LEDs, but I doubt that's going to fly for most people.

That reminds me of another thing... Can LED's be dimmed? As far as I've seen it's not possible. Some cars incorporate LEDs in taillights that in normal operation are dimmer than when the car is braking. However, that is achieved by flickering the lights which is far more noticeable than flickering fluorescent bulbs. Well, even CFLs have the same limitation.

Re:Concerns about LEDs... (3, Informative)

tftp (111690) | more than 6 years ago | (#24264929)

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:Concerns about LEDs... (1)

icegreentea (974342) | more than 6 years ago | (#24265153)

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 already better lighting tech (1)

scorp1us (235526) | more than 6 years ago | (#24264867)

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.

Re:There is already better lighting tech (1)

duggy_92127 (165859) | more than 6 years ago | (#24265055)

To paraphrase the internet as a whole: "Links, or it didn't happen."

Doug

Link (2, Interesting)

scorp1us (235526) | more than 6 years ago | (#24265303)

Luxim Plasma [treehugger.com]

Re:There is already better lighting tech (1)

funaho (42567) | more than 6 years ago | (#24265227)

Oh yeah I remember reading about those a few months back...the neat thing is they don't require any electrical contact with the fixture.

So what about (0)

Anonymous Coward | more than 6 years ago | (#24264881)

1) Motion lamps? ie Lava lamps? 2) Oven lights? 3) Fridge lights? OK, LEDs will probably work a lot better than CFLs in the cold, but is the color balance going to be the same as an incandescent? 4) Bread ovens where lamps are used to heat? 5) Toy ovens with a lightbulb?

So, which is more efficient again? (1)

plasmacutter (901737) | more than 6 years ago | (#24264895)

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.

Re:So, which is more efficient again? (0)

Anonymous Coward | more than 6 years ago | (#24265071)

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.

So you don't have a computer, refrigerator, dishwasher, television, or any other electricity using applainces?

Or have you just decided to compare two totally different things? Because a 10% cut in the total amount of electricity used in a house is going to include all the non-lighting electicity usage, while you seem to be assuming that lighting is the only electric thing in the house.

Forget Compact Flourescent (1, Troll)

lawpoop (604919) | more than 6 years ago | (#24264937)

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 light that we like. Those compacts have mercury in them, and all that mercury will be going straight into the landfills and our drinking water. The compacts have a life of 10 or so years; but we won't be using them that long, once LEDs come along. So the long-term money saving aspect will be a waste.
Also, I can't count the number of lamps and light-bulbs I smashed as a kid. Do you want your little ones smashing up these compacts and getting a good dose of mercury vapors?

I say just hold off until LEDs really become affordable. Don't put any more mercury into our environment; especially not your home.

LED already cost-effective in some situations (4, Informative)

rickkas7 (983760) | more than 6 years ago | (#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] .
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