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LED Light Fixtures for the Home?
HBergeron writes "Despite some exhautive searching I have able to find very little about LED based light fixtures for the home. There are some in marine use, and a spare handful of others come up on a Google search but from all I have read on Slashdot I have to believe there are more out there. I am in the final stages of a home remodel and would very much like to use 'the lighting source of the future' (tm) in a number of places. For one, the bedroom, LEDs could make a nice bedside sconce/reading light, and a red/white option could be just the like for those late night stumbling across the room expeditions. A vanity light seems like another good place. Not to mention energy and bulb replacement savings." While these may not be economical for most people, I'm sure there are a few folks out there who have put these new lights to the test. How well did they stack up to the use of traditional filament lights?
White LED lights actually are only as effcient as regular incandecset bulbs. If you are looking to save money you are better off going with CF, if you want effciency go with metal halide.
LED light bulbs
LED brass desk lamp
Several models to choose from
You would need some converters as well as LED driver chips to run the 'bulbs' optimally.
This is all doable; it's just a lot easier to use one of the many, many, many types of incandescent bulbs.
yea and thensome, you dont have to change them very much they dont get hot, dim, or annoying, i use them in my computer and as a reading lamp, the ones they use for homes, you can actually build yourself for about 20 bucks...no more ladders and stacked furniture, or those annoying how (blanks) does it take to change a lightbulb jokes, only how many resistors.
Dan covers this in one of his more recent letters sections. He states that compared to Halogen bulbs, LEDs aren't as efficient, and are best suited to accent lights.
But he says it better than I could.
I did some research on this a while back, with the intent to purchase or build some LED lighting systems. As it turns out, for practical, normal household use, LEDs aren't as efficient as some would have you think. You're better off with some form of flourescent lighting. Where LEDs shine is in spot-lighting situations - such as desk lamps, or small spotlights that go under the bottoms of cabinets to light up counters, and that sort of thing.
They provide more light per watt of energy consumed to a small focused area than other technologies, which spread their light in all directions and are masked/reflected to give light to only one direction. But for a main light source illuminating a room in all directions, they're somewhere in the same neighboorhood as incandescents in efficiency, and soundly beaten by flourescents.
11*43+456^2
As other posters have mentioned, the lumens/watt for LED is about the same as for standard incandescent. There are a couple of places where LEDs shine (so to speak).
One is in very low power systems where the LED's output/watt remains fairly constant but the lumens/watt for incandescent is extremely poor. The PALlight flashlight can run in "off" which is actually "very dim" mode for over a year with no problem.
Another is where you want long life and/or color such as in signal lamps. To explain: the lumens/watt for incandescent goes up dramatically with higher voltage but the lamp life decreases in a similarly dramatic fashion. That's why the bulbs on small flashlights where available power is a limiting factor often last only 4-6 hours compared to a standard bulb at nearly a thousand. Signal lamps are at the other end of the spectrum - they need to last a very long time but do so at the expense of efficiency. In addition, much of the light they produce is filtered out to get the necessary green, yellow or red. LEDs produce just the color you want so there are no filtering losses and they don't need to run at reduced efficiency to give long life.
LEDs beat flourescent where you need point-sources of light for focused applications like headlights. Some LEDs are now starting to get somewhat above the efficiency of incandescent and you may see them soon in auto headlights (I've seen a couple of prototypes - tiny led and big-a** copper heatsink).
Finally, LEDs are good in rough-service and high-vibration applications.
For general use around the house flourescent is far, far more efficient and currently far less expensive (last home LED light I saw was well over $100) and the new flourescents put out a very nice light - far nicer than any LED lamp I've seen. With the exception of a reading lamp my wife owned before we got married, every light in our house is flourescent and it really does make a difference on the power bill.
~~~~~~~
"You are not remembered for doing what is expected of you." - Atul Chitnis
www.ledtronics.com
They have lots of light bulbs, strips of leds, etc. as well as a bunch of other neat items (solar lantern, flashlights, flashing safety vests). Some of the household items simply screw into a light socket, others would require some sort of transformer.
:::Horrendous Experiences Make Amusing Anecdotes:::
This isn't really what you want, but it's cool enough to mention here. Target sells an Eddie Bauer branded flashlight that is roughly the same size as the AA Maglite. Except, it has 3 ultra bright LED's on it, which nearly blind you (brighter than the Maglite). They look like Xenon HID's on newer cars. And the best part of all, *200* hours on one set of batteries. $25, so it's a bit more expensive, but the coolness factor makes up for it.
A couple years ago, flashlights like that cost a couple hundred bucks.
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The laws of physics show that semiconducter LED technology can't achieve a better than 25% electrcity to light conversion, which would be under flourecent and about half metal halide. Currently white LED's are about 12% efficient.
I've got an old '67 volvo, and I was sick of the old-looking green backlighting in my dash. I replaced all the bulbs with blue LED's, and they look great. Kind of expensive, but they'll last forever. Smaller applications like this seem to be the most useful. though here in Eugene, OR, we've replaced the red and green traffic light bulbs with LED bulbs. Still waiting on yellow, a cost issue mostly.........
[este]
Frankly I look forward to having one or two "light boxes" in my attic keeping much of the heat out of my living space (or in the winter pulling it into the HVAC system), only having to replace a few well engineered super-efficient bulbs in a handy box every few years, plugging in a fiber cord instead of a an electrical one for a lamp. LEDs might become a good retrofit for older wired-not-fibered places but for new construction I'm looking to plastic.
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
Color Kinetics
They started out as a theatrical company, but they're moving into the architectural and consumer market. Pretty cool stuff, and with the pro line, you get a lot of control - either PC based, or from a wall plate with an embedded controller. -stubbie999
Color Kinetics have a number of LED light product lines, both professional and consumer. Their consumer branch, Sauce makes an assortment of wands, flashlights and nightlights, while their professional arm has done a number of Huge installations.
As for prices, I'm sure if you have to ask, you can't afford it...their 4 color intelligent nightlight looks relatively cool for $8.
I have two halogen torch lamps reflecting off the ceiling to provide area lighting, 300W beasties, and would love to replace them with flourescents. But every time I have bought a flourescent, desk or floor, it comes nowhere near the quoted equivalent wattage. One flourescent torch lamp is pretty disappointing, its maximum, with both tubes on, is less than the half maximum of the halogen.
Have you had this problem, and regardless of that answer, do you have any recommendations for flourescent torch lamps or wide area lamps?
Infuriate left and right
First, as others have noted they are not as efficient as compact fluorescents. Remember that they need low voltage DC so you have transformer losses to factor in.
Second, the less expensive ones are very, very "blue" in their output and have big dips in the output spectrum. The light is very "harsh".
Some co-workers follow LED technology for professional reasons (think of a place where spare light bulbs can only be brought up every 3-6 months at $10k/pound transport costs), and passed me some papers that project that they will probably be ready for home use by 2010, and industrial use somewhat before that. They already are starting to dominate in areas where the cost of replacement is high, or where a burn out is a safety hazard.
I can't believe I haven't seen it mentioned here yet (maybe I am browsing at too high a threshhold), but compact fluorescent lights are the current way to get the best bang for your buck in home lighting.
You get roughly a 4:1 amount of light per watt in a compact fluorescent as compared to a conventional incandescent bulb.
I recently went through my parents house replacing bulbs. I used mostly ~15 watt bulbs (60 watt equivilant) and in a couple of areas where really bright light was needed I used 27 watt bulbs (~100W equiv.)
There were two fixtures in the hall that used a total of 600W of light originally and now use a total of 60W using compact fluorescent bulbs. The hall is still quite bright, but now use four 15 watt bulbs as opposed to eight 75 watt bulbs.
It doesn't take a math genius to see that these bulbs pay for themselves relatively quickly via savings in the electric bill. Not only that, but they last a long time. I've been using them for about six years and I've had only *one* bulb die in that timespan (that was a Philips if anyone wants to know).
Home Depot is selling them pretty cheaply right now. There is no excuse to not buy a pack and try them out. You are totally justified in spending the money for the bulbs up front and put them in now, knowing that if you annualize your costs you are actually saving money.
These bulbs cannot be used in dimmer type sockets, and other than the really small 9 watt models some of them have a hard time in very small enclosed fixtures.
You will realize the most immediate savings if you replace bulbs that are in use for extended periods, like driveway lights or hallway lights.
On a whim last year, I bought an Ledtronic 9-led 4500K Incand White bulb
at a fire sale at my local alternative energy shop. It uses
approximately 0.6-1.2W of power, and produces light equivilant to a 15W
incandescent bulb.
But that said, it's sitting here on my desk, not in a socket. Why? When you turn it on, the light flickers and
whines (my guess is it's about a 60-hz flicker/whine, like an old TV);
and I have not found a good place to put such a dim bulb (perhaps when
I install my outdoor lights or build the shed in the back).
But this is an early generation bulb, so I expect the flickering to go away with a later generation.
"Can of worms? The can is open... the worms are everywhere."
The reason LEDs seem so bright is that they are essentially a point source of light, and they generally are designed for small viewing angles.
It would take quite a number of LEDs to match even a dim light bulb.
The reason LEDs are considered so efficient is that their light output is based on the current through, rather than the voltage through them.
Inefficiencies are introduced in the circuit used to power the LEDs. In most small circuits one would use a simple resister to limit the current. This resister typically wastes 2-3 times the energy that the LED itself consumes. This isn't an issue since one LED and resister should consume less than one tenth of a watt.
Cheap LED light bulbs for home use might use a simple resister scheme. If so, they will consume nearly as much energy as an equivilant incandescent bulb, and let off as much heat.
A truly efficient LED light bulb will have several high-output LEDs, and a small, 90%+ efficient switching current regulator. Such a bulb should still be more efficient than current lights. This can be shown by how little energy is given off by other (non visible light) forms of radiation, such as infrared light and heat.
-Adam
I have an off-grid camp and desired safe and efficient lighting. I loathe fluorescent light.
So I have a small (300 ma) solar panel charging a 12 Volt gel cell that I salvaged from a UPS.
Rather than use resistors or a dc-dc converter, I wired the LEDs in series. I made strings of 5 LEDs and wired the strings in parallel. (think christmas lights) Peak voltage on my circuit can be > 14.8v
Hints:
The light was extremely white/blue so I made some yellow strings and mixed them in. Cheaper that way too.
I used a cheap wirewound potentiometer as a dimmer because it was too bright for night reading.
I made the electrical connections into a self-supporting frame for the LEDs rather than using a backing material. That means the clear LEDs and fine wires disappear into the background. When it is off it is nearly invisible.
The LEDs I used (Hewlett packard, purchased from Newark Electronics) are extremely focused and directional. It took some careful aiming of the individual elements to get a good spread. You might consider a diffusor.
Good luck, and I will be happy to answer questions if you have any.
Next time I make some, I am going to make seperate red, green and blue circuits so I can tune the color balance.
-j
On sale, a string of 100 went for $6 USD at WalMart in January. Now...probably $20.
A firewall can not protect you from yourself. Turn off what you do not need. Do not use the firewall to do your work.
All fluorescent bulbs have dangerous amounts of mercury in them. Be very careful when handling fluorescent bulbs of all types--you may end up saving money and energy but at the expense of contaminating your living space with deadly mercury.
Kris
Kriston
Using them in the venue I work in and they really do look great!
YMMV on whether they're appropriate for your home application though! I would suggest, however, if you are going down the hardcore-lots-of-new-fixtures-everywhere route that you consider using fixtures that talk DMX, which'll make life a darn sight easier when you want your rooms to slowly change colour over the day!
Not LEDs, but I thought I'd mention that we currently have three Microsun HID metal-halide lamps in our house and are very happy with them.
Microsun makes table and floor lamps that are nice-looking pieces of furniture, mostly of wood. Not cheap but not out of line for "nice furniture." They incorporate a "gearpack'" which holds a 68-watt E17N metal-halide HID bulb and two conventional 25-watt incandescent bulbs.
The company claims "more than 300 watts [sic] [sigh...] of crisp white light, yet uses less than half the energy to do so." I think the claim is reasonable. The bulb package, annoyingly, does not state the light output in lumens, but such bulbs typically seem to have an output of about 5000 lumens. (The 25-watt bulbs, of course, don't add very much light but are just there to warm up and smooth out the spectrum).
That is, of course, not nearly as energy-efficient as fluorescent. However, most of the compact fluorescents we've tried really have fairly unpleasant color balance AND just don't put out much light.
These lamps put out a LOT of light and the color balance is quite pleasant. And they just look "normal," small bright sources of light inside a lampshade that light up the room just the way traditional lamps do.
Nothing revolutionary here, just nice, bright, ready-made, energy-efficient lighting with no "geekiness."
"How to Do Nothing," kids activities, back in print!
I don't much about LED's used for lighting, but I know your post is based on the little LED's you use in your little electronics projects. So, lets check out the power; you said 3 volts across the LED with 20mA through it, P=VI=(3V)(0.02A) = 0.06W Compared to a regular 60W bulb, your effeciency is amazing! Your LED consumes 1000 times less power than the traditional bulb....Unless of course you have no idea what you are talking about. I don't know anything about this stuff, so I don't post any BS about it. You should try the same.
Scientists restrict study to entire physical universe; creationist
- Lights of America lamps are very cheaply built, and the 3-way ballasts destroy themselves when the bulb starts to die. The bulb is supposed to be replaceable, but if the ballast is dead you have to buy a whole new unit.
- I bought some "Eco-Bulbs" (Feit Electric, made in China) and they all croaked in less than a year of relatively undemanding use (though many starts). The dead units were the folded-tube, frosted-plastic cover type, but the one I took the cover off of for better cooling lived no longer than the others. I have a naked spiral tube unit of the same brand (13 W) in a desk lamp, but it does not have enough hours on it to get any idea of the longevity.
Them's my experiences; your mileage may vary.Scientists restrict study to entire physical universe; creationist
It's pretty hard for a crystal of gallium indium phosphide to generate mechanical vibration (no piezoelectric effects that I know of, and no variation in the applied voltage to drive it) or EM at other wavelengths other than thermal IR at the temperature of the device (what quantum processes exist to produce photons at near-IR wavelengths?). So the answer is "You can bet on the remaining energy going to make the device warm."
Scientists restrict study to entire physical universe; creationist
On a recent science or medical info radio program,
it was said that:
- rates of breast cancer in women may be linked
to the amount of time they work in artificial
lighting (eg office flouro's)
The research found that women who work at night,
presumably in artificial lighting, have higher
rates of breast cancer.
Blind women have much lower rates of breast
cancer.
'don't know if it matter -which- type of
lighting they're experiencing, but it might
be good to know... ie -before- choosing
a lighting system technology for the home.
I don't have a link to the original Danish
research work, but here's a German link:
www.labournet.de/diskussion/arbeitsalltag/gh/br
Other links are available; cf:
Google("breast cancer" artificial lighting blind rates)
Sort by TIME/DATE before you mark posts as redundant.
Idiots.
> Blind women have much lower rates of breast
cancer.
Could it be because they're not pumping gas and otherwise exposing themselves to chemicals like sighted women are?
You should check out the Luxeon Star LED. It is a little larger than the average LED but has the light output of 20-25 smaller 5mm LED bulbs. They even make drivers for it that simply require you to attach the emmiter. So I would suggest checking out the Luxeon Star site. http://www.lumileds.com/luxeon/products/products_i ndex.html
OTOH, with Solar/wind and batteries, running 48VDC is getting less uncommon. LED's like 48VDC 9with big resistors.
You don't mention that the EB lights happen to also use 3 N cells, which are much more expensive and harder to find than AAs. None of the LedLensers (The EB lights are rebadged "LEDLenser" lights from a German company named Zweibruder - I think their website is www.zweibruder.de) have DC/DC upconverters, so if they run on AAs or AAAs, they need 3 cells, and for 2AA form factor they must use N cells.
If you want BRIGHT LED flashlights, look around on http://www.candlepowerforums.com/ - The creations of forum users ElektroLumens, Lambda, McGizmo, dat2zip, and Mr. Bulk are simply incredible. dat2zip sells an excellent drop-in for MiniMags that includes a DC/DC converter circuit and a 1 watt Luxeon LED. (Equivalent to 10-20 of Nichia's best 5mm units.)
retrorocket.o not found, launch anyway?
The way fluorescent lights work is that the gas in the tube emits UV light, which is absorbed and re-emitted as white by the phosphors in the light. A decent amount of this UV leaks through...
White LEDs are similar, except that they use blue light (much safer) to charge up the phosphor.
retrorocket.o not found, launch anyway?
http://www.luxeon.com/
Currently the largest LED is Luxeon's 5 watt emitter, which gives off around 100-120 lumens. No one has been able to manufacture anything larger easily yet. There's a rumored 10W LED coming from another company, although its light output is specced as LESS than Lumileds' Luxeons (i.e. it's less than half as efficient.)
5W units are $40/each in small quantities, dropping to $24 or so each in larger quantities (100+) They are VERY hard to obtain.
retrorocket.o not found, launch anyway?
Go to http://www.candlepowerforums.com/ - It's the closest thing you can get to a "Luxeon Star User Group" :) - There are a lot of flashlight modders there that use LOTS of Luxeons in their projects. People have started using Luxeons elsewhere, too. (One guy on the forums builds Luxeon-based replacement dome light modules using 1W white LS units + a DC/DC converter circuit he designed himself.)
Very little in the terms of line-powered lights, but people are starting to experiment (very carefully...) in that area.
retrorocket.o not found, launch anyway?
LEDs are indeed the light of the future.
I.e. they aren't the best choice for light today,
however they have been improving at close to what Moore's law predicts,
so perhaps in 10 years, they will be the ultimate light source.
Today however, they are still too expensive (90 dollars vs 90 cents for a standard bulb) and only a little more efficent.
Last year the light/power breakdown was something like this:
Lumens/Watt Light Source
100-190 low pressure Sodium (HID)
50-150 High pressure Sodium (HID)
60-140 Metal Halides (HID)
20-60 mercury vapor (HID)
85-95 32 watt T8 fluorescent
60-65 standard F40T12 cool white fluorescent
48-60 compact fluorescents
45-55 Super bright Red/Orange LED
35-45 Super bright Green LED
20 T3 tubular halogen
15-25 bright white LED
5-25 Halogen
17 standard 100 watt incandescent
6 incandescent night light bulb (7w)
<6w incandescent flashlight bulbs
The best choice for the home today is almost certainly the cool white tube fluorescent, with an all electronic balast.
They don't "whine" or flicker like the older fluorescent lights,
the tubes cost about $2.00 US, they are near the top in efficiency, and the last for years.
The down side is that they require special fixtures, and they flicker more than incandencances, which is a problem for some people.
Compact flourescents are the next best choice,
but they don't have "instant on" which can be annoying for some rooms.
In my kitchen, I have an old 3 socket fixture.
I use two compact flourecents and a long life incandescent and it works well.
Yes, this is the third time I've made essentially the same post, what's your point?
Your average fluorescent bulb has less mercury than your average thermometer.
Your average compact fluorescent has far less mercury than your average fluorescent.
So for God's sake, please stop taking your temperature before you die!