Nichia Develops 60 Lumen Per Watt White LED

Buck

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As much as I like my fancy fluorescents in the shop, I prefer incandescent everywhere else (although I don't always use them). For some reason, the warm light of an incandescent bulb just seems right in the house. I enjoy reading by it, and it works particularly well for dimming. I don't like bright lights, so the fewer the better. Now, I have two desk laps in the house that use flourescents. I'm more comfortable with a low-heat emitting, low-power consumption bulbs for lamps that stay on for hours.
 

Will Rickards

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Sound really cool to be able to coat something with this substance and then send a small voltage across to get light. Imagine a celing paint of sorts.
 

jtr1962

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LiamC said:
I think I have commented on this before--I'm the opposite. I find most flouro's too "cold", and with the blueish ones, I find the cold light lacks a significant amount of contrast to my eyes--to the point I find it difficult to focus--and this with a 100W compact flourescent versus a 75W incandescent. Warm white flouro's I find much better, but not as good.

In fact the best lights in my house are in the bathroom, the 4 x 575 infra-red lamps :)
Most of those compact fluorescents are warm white, and regardless of color temperature preferences their spectrums leave something to be desired. I think I mentioned in the other thread that the relatively poor spectrums combined with in some cases flicker from magnetic ballasts might account for your dislike of "cool" lighting. After all, compared to incandescents, the sun is a "cool" source yet I rarely hear anyone complain about it unless they get sunburned. A person really can't say they dislike cool lighting or fluorescents until they've tried full spectrum tubes similar to what I use. There's a world of difference between those and the cheap, generic cool/warm whites commonly available in Home Depot.

BTW, I read somewhere that cooler lighting tends to look better if you have more of it. If you prefer relatively dim lighting as Buck does that might partially account for why you find cool lighting less than pleasing. Me, I like things lit up like ballparks. My bedroom ceiling fixture puts out the equivalent of about 600 watts incandescent, for example. Despite that, light levels are still less than 10% of what you'll have on a sunny day but I can't afford to run 40 32 watt tubes to simulate exact daylight conditions.
 

Buck

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jtr1962 said:
A person really can't say they dislike cool lighting or fluorescents until they've tried full spectrum tubes similar to what I use. There's a world of difference between those and the cheap, generic cool/warm whites commonly available in Home Depot.
Indeed, there is a difference. As a printing press operator, I worked under full spectrum bulbs to help provide correct color comparisons. They were great in that environment and for that purpose.

jtr1962 said:
BTW, I read somewhere that cooler lighting tends to look better if you have more of it. If you prefer relatively dim lighting as Buck does that might partially account for why you find cool lighting less than pleasing. Me, I like things lit up like ballparks. My bedroom ceiling fixture puts out the equivalent of about 600 watts incandescent, for example. Despite that, light levels are still less than 10% of what you'll have on a sunny day but I can't afford to run 40 32 watt tubes to simulate exact daylight conditions.
:D You can do it jtr, yes you can!

If anything, I have found that lighting is terribly subjective and my eyes are extremely sensitive. I have no problem walking around my house at night in the dark. With stairs unlit, I can easily walk them. At night, I have my window covered with darkwood blinds and darkening curtains. All small light emitting sources in my bedroom (eg phone, electric razor in bathroom, etc.) are covered. The only two sources of light that I don't cover are my digital clock 14 feet away from me (closer, and I can't sleep) and the LED for the smoke alarm (normally only apparent in my peripheral vision). Door needs to be shut, and the hallway stays almost all dark (otherwise the light would shine in under my door). However, when I'm working in my shop at night, I like as much light as possible. Over my workbench I have 12 32 watt bulbs. I've slept through some pretty noisy events, but you change the light in my room and I'm awake. I don't know, maybe it's the fact that I look straight at a huge lightbulb most of the day working in front of a computer that has affected my sensitivity to light. Funny, I remember that as a kid, I hated the dark. Now I can't get enough! :-?
 

jtr1962

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Buck said:
As a printing press operator, I worked under full spectrum bulbs to help provide correct color comparisons. They were great in that environment and for that purpose.
They're also great for room lighting and SAD. I find I feel much better since switching over from regular fluorescents.

However, when I'm working in my shop at night, I like as much light as possible. Over my workbench I have 12 32 watt bulbs.
Wow! You're even worse than me. :mrgrn: Hmm, come to think of it, that might not be a bad idea....

Funny, I remember that as a kid, I hated the dark. Now I can't get enough! :-?
I can adapt well enough to dark myself, even getting around by the light of one underdriven LED. As a rule though, I like light, even when I'm sleeping. I have trouble sleeping in a completely dark, quiet room. In fact, I usually need a TV on to fall asleep.
 

jtr1962

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I read that on CPF although I'll take it with a grain of salt until I can actually buy the LEDs. Still, it's an interesting development for two reasons. One is of course the increased efficiency, and the other is that they're converting purple light to white without a phosphor (that should mean cheaper white LEDs and more consistent tint). It's interesting also in that we're way ahead of the timeline laid out several years ago which called for 150 lm/W LEDs by 2012. Even without this development it looks like we'll get there at least two years early. With this development that might occur 4 or 5 years ahead of time. Not bad, and at this rate we may even get well beyond 200 lm/W by 2012.
 

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I now have a real problem that I think would best be served using LED lighting. My GF is a jeweler (http://www.kupkepeyla.com) and goes to shows where a booth must be constructed to display her work. I just went to a show with her in SF and was really amazed at how much work her current configuration involves.

One of the components in the new solution I'm working on is display cases 18" on a side, about 6"-10" deep, and internally lit like a ballpark. Here's the requirements:

1. As wide and tall as possible, while no more than 10" deep. Thinner is better, but more difficult to light.

2. Maximum white light (5000K+) is a requirement. This will be replacing 1kw of halogen bulbs.

3. Minimum heat production - these lights will be close to work that people are trying on, best it not heat the work at all.

4a. Minimum power consumption - we paid nearly $1000 to increase our power allowance from 500W to 1000W for 2 days!

4b. Possible battery support? Our power went out 8 times for a total of 2 hours. Cutting dependancy is a good thing.

If this proves viable, a solution will be bought/built soon. If anyone knowledgeable cares to contribute, it would be greatly appreciated.
 

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Sorry, but it sounds like an ideal application for florescent lighting but LED's would be good too (Just more expenisve).
 

jtr1962

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The problem is right now LED efficiency isn't high enough to appreciably reduce your power consumption. Maybe with LEDs you could get by with 500 watts worth since they are roughly twice as efficient as incandescent lamps, and you'll need a huge heatsink to mount them on. Even with T-8 fluorescents you'll still need about 200 watts worth (6 4 foot 32W tubes). However, those would not meet your size constraints.

Look into metal halide lamps. One 250W lamp would do the trick. In fact, it would probably give more light than the halogen lamps. There are 5000K metal halide lamps available with very high color rendering. Here are some which look good, although they're probably pricey.
 

ddrueding

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After talking more with the artist (anyone here try working with an artist on a technical project?) It seems the power consumption is a lower issue and the ability to provide unobtrusive lighting with both a wash and steerable spots. I'm still interestd in going the LED route, but am curious how much power/light/heat I'm going to have to deal with. The other big plus in the LED lights is the durability; a half-dozen halogen bulbs break every time (especially in halls where union labor is handling the freight from the dock to the booth).

So. Here's some more speific questions:

Are these the brightest comonly available LEDs?
Are they appropriate for my use?
Is this a good price?
What would I need to do to mount them?

I'm roughly familiar with the wiring needed to finish off the job, but suggestions on AC->DC power supplies with an output near the correct voltage and of a sufficient size would be appreciated.
 

jtr1962

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ddrueding said:
I'm still interestd in going the LED route, but am curious how much power/light/heat I'm going to have to deal with.
If you have 1000 watts of halogen bulbs then that's roughly 15,000 to 20,000 lumens. I could be more exact if I knew the specific bulbs. In any case, you're looking at 300 to 500 watts worth of LEDs to replace that. Forget the 5mm and 10mm ones. Granted, right now they're more efficient than the power LEDs such as Luxeons, but only by about 50%, so you'll still need about 350 watts worth. On the downside, since you can only drive them at roughly 30 mA each, and you'll be getting 5 or so lumens out of them at that current level, you'll need at least 3000 for this project.

Are these the brightest comonly available LEDs?
They're bright but brightness doesn't directly equate to lumens. Those have a very narrow bean angle, and the tints are wildly inconsistent.

Are they appropriate for my use?
Is this a good price?
In a word, no. Me and other people have run tests on these. They lose half their brightness in the span of a few hundred hours so they're really only suited to intermittant duty items like flashlights or bike lights. In fact, the same problem exists with all 5mm LEDs, and more so with the cheap Chinese ones on eBay. Granted, the better ones don't dim significantly until a few thousand hours so those might work for you, but the eBay ones are hit or miss in that area. Some may last, most don't. Nichia 5mm may be your best bet but they run $0.53 or so. You'll need at least 3000 so figure on spending over $1600. You can get them here.

A better bet is power LEDs like Lamina or Luxeon or Cree. Per lumen Crees are probably the cheapest. Each Cree LED puts out roughly 55 lumens and costs $4 (maybe less in large quantities). For this project you would probably need about 300 LEDs and at about 1.05 watts each they would use ~315 watts. Naturally, they need to be mounted on a heatsink. My reason for suggesting power LEDs is durability. Most are rated to last 50,000 hours so you'll never have to worry about them dimming.

What would I need to do to mount them?

I'm roughly familiar with the wiring needed to finish off the job, but suggestions on AC->DC power supplies with an output near the correct voltage and of a sufficient size would be appreciated.
They would need to be mounted on an aluminum heat sink, and given the size constraints the heat sink would need to be fan-cooled. You could also have many smaller heatsinks if you want steerability but since Crees and other power LEDs are wide beam angle you would need a lens to focus them. For wiring I would put them in 100 series groups of three, with each group controlled by a 350 mA constant current source. For power a PC power supply might do, but you would need one capable of putting out about 35 amps on the 12V line. Alternately, you could put the LEDs in longer series strings and run them directly off rectified 120VAC. Figure filtered, rectified 120VAC would give you about 165 volts. Allowing about 3.5V per LED, and a 5V cushion for the regulator, you could put them in 7 series strings of about 45 (meaning 315 LEDs instead of 300). Overall this will mean a simpler circuit and less power consumption. Naturally, since you'll have high voltages you need to have some means of preventing accidental contact with the LEDs

As I said, I'm not sure you're gaining anything with LEDs over metal halide except durability. If durability is an issue preventing use of metal halide, then consider shipping the booth without the bulb installed, and putting it in yourself before the show. Overall metal halide will serve you better than LEDs (better color rendering, far less complexity, cheaper) but LEDs are possible for this project.
 

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Durability is a big factor on this project, but total on-hours really isn't. They will be on 12 hours a day, 4 days a month. If they last for 2 years (1152 hours) that's fine.

Actually replacing the total lumens of 1000w of halogen is also not required. Those 1000W are currently illuminating 100sq ft of booth space while suspended 8 feet overhead. By using compact steerable spots and close-range floods specifically into the ~10-15 sq.ft. of display case should save us from all the wasted light. I do have her interested in using the Halide lights as a flood for the entire booth (lower light levels should allow one or two of these to do the job).

Basically what I'm looking at is lighting 6-8 18"x18" cases both with a general flood light and certain items (2-4 per case) in the case with enough of a spot to accent the items. As low a profile as possible.

Thank you for all your help so far, it is much appreciated.
 

jtr1962

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OK, now I understand a little better. 1000 watts to light a few 18"x18" cases really seemed like a lot. Now I know it was also for general lighting of the booth area. Anyway, to light an 18"x18" case to 1/10 the equivalent of full sunlight requires a light level of 5000 lux or 500 lumens per square foot. For each case then you would only need maybe 1000 lumens or so. This is very possible with power LEDs. 20 or so of the Crees per case will do fine, or maybe 250 of the 5mm Nichias. The Crees would run you roughly $80 while the Nichias would be about $125. The Nichias simply need to be mounted on a circuit board (a few Radio Shack perfboards would work). How you connect them depends upon the voltage of the power supply. The Crees would require a decent sized heat sink but in either case you'll only be dealing with about 20 watts of power per case, and one PC power supply should be enough for all your cases. I would recommend the Crees or other power LEDs like Luxeons for their longevity. The Nichias would probably not dim too much after 1125 hours, but for all you know you both may find other uses for these cases (i.e. photography booth) and might run them a lot more than you're anticipating.

As for spots, maybe a few steerable clusters of about 50 or so 5mm LEDs or a few Crees with lenses to focus them will do. What kind of time frame do you need these in?

BTW, here's what I came up with for my taxi project:

Lamina_3.JPG


That's a picture of about 20 or so units. Each unit uses 6 Lamina BL-2000s on a custom aluminum heat sink. Output per unit is ~650 lumens so you're looking at ~10,000 lumens of LED light in that picture
 

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Awesome. Thanks for the information (again).

I'm really liking the idea of using th 5mm LEDs on the spots. an aray of 7x7 would only be 4x4cm. More questions:

1. Can they be mounted this closely?
2. How much heat would be involved?
3. Any ideas for a flexible/steerable clean-looking mount?

Thanks again.
 

jtr1962

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ddrueding said:
1. Can they be mounted this closely?
2. How much heat would be involved?
Shouldn't be a problem since each spot would only be dissipating about 3 to 3.5 watts.

3. Any ideas for a flexible/steerable clean-looking mount?
Not really, but maybe you can adapt mounts for MR-16 halogen bulbs. In fact, eBay has premade LED arrays designed as drop in replacement for MR16 halogens. I believe they're also designed to run off 12V. In fact, here are a few. 48 LEDs each and price starting at $14.49 each.
 

jtr1962

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mubs said:
I wonder what jtr will have to say about this: Myths Busted, LED Lighting
Most of what they say is true for the current state of LED technology. However, let's look at what happens as things get better:

Light Emitting Diodes are just now (in 2005) claiming to double the lumens-per-watt of typical incandescent bulbs. HID (High Intensity Discharge) lamps are still 4 or 5 times higher, and LEDs may never reach that efficacy.
LEDs have already been lab-tested at HID efficiencies. It's only a matter of time before such LEDs are commecially available. Cree and several others claim that 100 lm/W power LEDs will be commercially available by 2007. This is actually ahead of the planned time table. We may have LEDs 50% more efficient than HID by 2010 or so.

LEDs may produce a little more light per watt than a bulb. But most of the watts they consume is still converted to heat, and if not gotten rid of will drastically shorten their life. Heat from a LED is not easy to manage, and the LED must operate below about 85°C.
Yes, this is true, but as LED efficiency goes up the amount of heat you need to manage goes down. For example, today's 30 lm/W LEDs convert roughly 10% of their power to light. If you want to light a room with 1500 lumens you would need 50 watts of input power, and would have to get rid of 45 watts of waste heat.

Now consider doing the same thing with 150 lm/W LEDs. For starters you only need to have 10 watts of input power to get the same amount of light. A 150 lm/W LED converts about 50% of its power to light. That means of the 10 watts input, only 5 watts are waste heat instead of 45 as before. 5 watts is quite easy to deal with.

Now the barrier to keep an eye on for the illumination business is not these few percent of inefficiency, it's the LED's high cost per lumen. HID bulbs can jump in increments of a thousand lumens for mere dollars, whereas LEDs cannot.
True for now. As LEDs get more efficient a package producing 70 lumens today might produce 350 lumens for the same power, and costs of that package will gradually drop. In time per lumen LEDs will probably not cost much more than conventional lighting. Even at today's prices, LEDs often pay for themselves in hard to replace installations.

LEDs have a reputation for long life, but they are also easily abused. Light Emitting Diodes are more fragile than some designers are aware, but electrical or thermal deficiencies in their fixture design will not often cause a sudden failure. Too much current or too much heat for example, could result in a 50,000 hour part lasting only ten-thousand hours.
This is more a problem of engineers not being aware of how to design an LED into a system than anything else. LEDs must be driven by constant current circuits, not constant voltage. I cringe when I hear someone talk about how many volts an LED takes. Treating an LED like an incandescent light is a sure path to failure.

High quality, high output monochromatic LEDs can provide 70% of their original lumen output at 100,000 hours IF they are not abused. Note that Monochromatic is stipulated because the Phosphor in most white LEDs can degrade faster than the LED junction itself. This can be caused from thermal overload or from excessive ultra-violet exposure. Some manufacturers have overcome these problems, now the integrator must adhere to good science.
The white lifetime issue has been solved with silicon encapsulant. LEDs like Luxeons will last 50,000 hours with only 30% lumen depreciation.
 

mubs

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Thanks jtr. An odd thing I've noticed is with traffic lights that have been converted to LEDs. I see many greens with quite a few LEDs in the matrix that are dead -- 10% or less, but they are visibly dark when the green light comes on, but they don't affect the overall quality of the signal. I have never seen a dead red LED in a traffic light, though.
 

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mubs said:
Thanks jtr. An odd thing I've noticed is with traffic lights that have been converted to LEDs. I see many greens with quite a few LEDs in the matrix that are dead -- 10% or less, but they are visibly dark when the green light comes on, but they don't affect the overall quality of the signal. I have never seen a dead red LED in a traffic light, though.
That's impossible!!!

http://www.lumileds.com/newsandevents/releases/PR42.pdf

:wink:
 

mubs

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It's impossible that's it's impossible - I see these on a daily basis! :D

Perhaps the ones I see are not made by Lumileds. Just to clarify, the lights I see are a matrix of individual LEDs, whether for the red or the green signal. Individual green LEDs don't light up. Whether this is because the LED itself is dead or is not receiving power, I wouldn't know of course. Thankfully, unlike in the previous circumstance where the entire signal (red or green) would be dead, it is now only a tiny portion, with the rest of the light lit up brightly enough to see.

Sheesh, I'm having trouble articulating myself today.
 

i

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JTR ... (or anyone else for that matter) ... have you come across a 120V-capable LED light with one of those smaller screw-in bases? I think they're "Type G" bases or something.
 

jtr1962

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i said:
JTR ... (or anyone else for that matter) ... have you come across a 120V-capable LED light with one of those smaller screw-in bases? I think they're "Type G" bases or something.
Nothing with any decent output yet but those small-base lamps will definitely be among the first to offer LED replacements since they're the most inefficient of all common household incandescent lamps. The 40 watt ones only put out about 450 lumens. We can do this with LEDs today using about 15 to 20 watts. In a few years we'll be able to do it using only 5 to 7 watts.

Give it about two or three years and Home Depot will have them I'm sure, and hopefully in a few common color temperatures instead of just yucky warm white. I'm hoping for these myself so I can ditch the incandescents in our three chandeliers (seldom used but the color of the incandescents annoys me).
 

Bozo

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Bulb sockets are labeled as 'miniture' , candelabra, edison base, and mogel.

Edison base is the most common house hold lamp base. Candelabra are used in Christmas lights and the candles that you see in the windows of houses. Mogel (Mogle sp???) was used in industrial and commercial lighting before flouresent lights. (a screw in type bulb) They are now used in Mecury Vapor and High Pressure Sodium bulbs, and some others.
Miniture are are those pain in the ass Christmas lights that work when they want to. But there seems to be two different typs of minitures. Some plug into the socket, some screw in.
There are also 'grain of wheat' bulbs used in model trains and such.
And then there are tons of specialty bulbs and bases, like for cars, instument panels, and control panels etc.

Bozo :mrgrn:
 

i

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I'm contemplating whether or not to just stick a wad of magnesium ribbon in the socket instead. :)
 

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Stereodude said:
Your document was written on October 10. Maybe Lumiled's leds where guaranteed until November and they are like video tape recorders that fail the day following the warranty. There's a lot of time to fail between October 10 and December 20 (when Mubs posted). Who knows :roll:
 

jtr1962

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i said:
I'm contemplating whether or not to just stick a wad of magnesium ribbon in the socket instead. :)
At least the color temp will be nicer than incandescent, for the second or so that it burns anyway. :mrgrn:
 

jtr1962

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Thanks for posting that, mubs. I saw it a few days ago and was going to add it to the thread.

113 lumens per watt is well into HID territory. We are way ahead of where we thought we would be now. Remember that less than three years ago 60 lumens per watt existed only in the lab and 20 to 25 lm/W was typical of commercial white LEDs. Just last week some white LEDs I purchased on eBay tested at an incredible 82 lm/W (125 lm/W running at 1 mA). Now we hear Nichia has hit 113 lm/W, plus many in the field feel we'll hit 200 lm/W sometime in the next ten years. When the next generation of 100 lm/W power LEDs hit the markets around 2007 we'll see the beginning of the takeover of general lighting by LEDs. Although forecasting the future is difficult, I'd say you'll be hard-pressed to purchase an incandescent light bulb by the early 2010s, if not sooner.
 

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Fluorescent light bulbs have been on the market for years and yet, they haven't replaced incandescent in most houses, despite the fact that they are way more efficient. Why? They cost more (not on the long term, but they are more expensive at first) and they are often bigger so they don't fit everywhere. Unless white leds come cheap and small (and last longer than the Energizer bunny), they won't displace the traditional incandescent light bulbs either. Size won't be a problem, but price, I'm not sure.
 

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CougTek said:
Fluorescent light bulbs have been on the market for years and yet, they haven't replaced incandescent in most houses, despite the fact that they are way more efficient. Why? They cost more (not on the long term, but they are more expensive at first) and they are often bigger so they don't fit everywhere. Unless white leds come cheap and small (and last longer than the Energizer bunny), they won't displace the traditional incandescent light bulbs either. Size won't be a problem, but price, I'm not sure.
The early fluorescents, meaning the linear ones found in most offices and the kitchens of some homes, had poor color rendering plus flicker from the magnetic ballasts. Later fluorescents overcame these difficulties but nevertheless many people did and do continue to associate fluorescent with poor lighting. That has hurt sales. Until recently screw-in fluorecent bulbs didn't become cheap enough to get people to switch. Most people won't spend $20 now on a bulb which will save them many times that in the long wrong. However, now that compact fluorescents are often $2 or less, plus no bigger than the bubls they replace, people are starting to see the light (no pun intended). However, most still do have the disadvantage of not being able to be dimmed, and they don't like to be turned on and off frequently. Also, the replacements for small base bulbs aren't common or cheap as of yet.

LEDs on the other hand suffer none of these disadvantages. I'm sure once they make screw-in household LEDs they will be dimmable with a standard lamp dimmer. The only thing which will hold them back in the beginning will be their higher price. However, like everything electronic they are falling in price fast with mass production. My guess is a few years after their introduction they will be nearly as cheap as incandescents. They have the potential to be far cheaper since they use less raw materials than incandescents, and nothing terribly exotic or expensive such as th argon fill gas used in bulb manufacture. I imagine you'll have LEDs with all the driver electronics built in to allow running straight off 120 or 240 VAC. Add them to a screw base and there is your LED bulb. They'll probably cost well under $1 at any store where you can buy bulbs now while being ten times as efficient and lasting 50 times longer.
 

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CougTek said:
jtr1962 said:
...nd lasting 50 times longer.
Leds last longer than fluorescents?
Compact fluorescents last 6,000 to 10,000 hours. Typical T8 or T12 linear fluorescents last a bit longer-from about 15,000 hours up to about 35,000. Present-day power LEDs with silicon encapsulant maintain 70% of their initial brightness after operating for 50,000 hours. Future ones may well last 100,000 hours or more. So yes, LEDs will last longer than fluorescents. Running 6 hours per day a 50,000 hour LED would last nearly 23 years compared to less than 3 years for a 6,000 compact fluorescent.
 

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jtr1962 said:
Although forecasting the future is difficult, I'd say you'll be hard-pressed to purchase an incandescent light bulb by the early 2010s, if not sooner.

I'd say the opposite.
 

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Do LED's run hotter than incandescents for the same light output? Would that be a problem (like halogen's in some light fixtures)?
 
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