LEDs

LED lamps have a higher initial purchase price, but they make up for it through lower power consumption and much longer service life as compared to normal energy-saving lamps.

As DVader1000 noted, LED's are suppose to have a longer service life: IE: how long they'll last. He's also noted that they are more expensive than 'normal' lights whither they be 'normal' or 'energy efficient.' The LED's are suppose to last around 5 years and use less power than 'normal' and probably 'energy efficient' ones too.

Currently the only 'bad' thing about LED's is trying to get the 'right light' from them... Since many - even from the same batch - can be slightly different from one to the next... Getting the lighting 'even' or 'just right' may become down right out ragious.

Now, if I where to 'build' a new house, then yes I would want the LED's as the main lighting because of the 'low maintenance' and efficency. Not to mention the possiblity that if at some point you may want or need to put the house up, that may just give more value to the house... With that being said, if you do go with LED's, then please do yourself and anyone else whom may buy the house a favor and purchase a few replacements and possibly one entire set of 'spares' so you don't run out... Why? If the one's you buy are discontinued... And the fixtures that 'they' use go discontinued too... Then again, it'll be expensive to buy an entire replacement system...

So - you probably should do some homework lol Especially on what LED's are available :)

thx all so far for the valuable comments/advice...appreciate if u can tell ...hear what u are saying about it being cost efficient, etc...but from a technical perspective:

- what is it that makes LED so much more superior to the normal energy saving bulb..

- the difference between the many various LED (since many countries and companies are now pursuing aggressively to manufacture them.)

- am sure the ones from China/Taiwan will be alot cheaper than say the Koreans... so should I then go for the cheaper ones...

What I've noticed LED v. CFL

When CFLs came out I thought great! a bulb that will last! wrong!!! The CFL is supposed to last at least 5 - 7 years, I was lucky to get 6 months. And don't think you can just throw them away either. You have to follow the EPA guide lines, something about them being toxic and containg Mercury.

When I use LEDs it is in control panels I build, so I can't comment on using them in a house. But ever since starting to use them roughly 7 years ago, I haven't had to replace any. Be sure to get the full specs on the LED bulbs you get, some of the cheap ones will say the have a low mA consumption. Turns out they consume more.

To be honest, I don't trust anything coming out of China! Eventhough I don't have choice, almost everything is made in China.

LED lights could do away with the concept of a socket. The socket was based on the incandescent lamp which burned out.

You get a properly designed LED lamp and the life is essentially infinite. The stories about limits of 100,000 hours etc are due to operating them at that envelope, where they lose. Run them a little cooler and they last lots longer but at 100,000 hours = 50% of the light after 100,000 hours, which is about 11 years. I have seen LED pilot lights installed in the late 70's in continuous operation ever since.

A badly powered LED light can fail in a millisecond.

John M

You got a GA from me! That was an excellent, and excellently organized answer! And tremendously informative without being pedantic! Thanks!!

Mike

jmueller:

Very informative answer. I have been waiting for the market to come up with suitable LED lights for my home. I have 76 halogen type pot lights all dimmable but nothing to replace them with economy. I have found similar issues as outlined in your good reply. I am optimistic that the demand for energy saving will create a good answer for new homes and perhaps retrofitting older homes. However, I suspect that the lighting as we currently know it will change dramatically from point use to larger sheet or wall like use.

Anyway it goes, I think that we are coming up on the point where the manufacturers on the ground floor of making the really high-power designs (not the devices that use them, which is were most of the over-driven designs are coming in, but the actual "growers of high-powered silicon", though they may not long be silicon) are going to be the McDonalds stock of the day. i.e., buy in, sit on it, and wait a while. As long as you choose well now, monitor the trends and the company's reaction to the trends, you MIGHT do well in the future. I'm hoping. Not a lot of my investment is in it, but it is carefully chosen, and I'm sitting on stock that is steadily, but in small increments, growing, and waiting for that "knee" function that heralds the recognition of a break-through. I think its coming, when we move in huge part, for most of what we currently use incandescent lamps for, to LEDs. And as one poster said elsewhere (can't remember who now, nor find the post) CFLs, which were/are SUPPOSED to be the answer of the day, are just so much hype. Too little green, due to Mercury, and not enough longevity. So my money, in more than one way, is on the switch from traditional "hot" bulbs, to LEDs.

And a factor most people don't discuss much is the downstream effect in summer of using LED lighting. Since they waste such a small portion of their power in heat, if designed in properly, HVAC costs will go down. On the down side, though, heating costs may go up in winter, where the winter days are significantly shorter (nearly everywhere that is non-equatorial, and where we thus use our lights for longer hours, reaping more general heating effect) we lose that heat that the hot designs produce. Of course, to ramble on about it, that heat always hangs around near the ceiling, anyway, so it doesn't help us down here a lot, does it? So, all in all, I think LEDs are going to make a profound difference on cost, life, greening of the world, and a lot of other things we generally want, though we may prioritize them differently.

Mike

Good write-up but.....

1.) Not all diodes emit light; "diode" means two (electrodes) and it can only be said that all diodes conduct in only one direction. You probably know, the first application was the Electron Tube, used for rectification.

2.) Electronic Ballasts in most modern Fluorescent applications also employ switch - mode power supplies, increasing efficiency and raising the frequency , substantially.

3.) And yes, there are now a multitude of very efficient R-134a domestic refrigerators on the market, even at Sears. But I can't really say you didn't note this.

Good response, John M!

In the refrigerator alternatives yahoo group we were talking about refrig electric costs, the newer fridges use around 35-$45 a YEAR worth of electricity. Your water heater uses more than that,and the major power hog is the central heat/ac unit. As for lighting,the cfl bulbs do a good job for relativly low replacement and energy costs. You would have to spend,at current prices a couple of hundred dollars to get the light output that a single $4 18watt/replacing 100watt incandescent bulb puts out. However,as previously noted,cfl's do not last as long as they say on the box,because they do not handle being turned off and on very well. Mythbusters was able to render several cfl bulbs useless in just a few days,turning them off and on repeatedly. led lights,on the other hand,showed no difference and none failed to function after 10,000 off and on cycles.I have several cfl bulbs that have lasted 3-4 years so far, but they are not in high cycle areas,like the bathroom. For lights that will be turned on and off frequently, i use led's, like in the bathroom.However,they provide enough light to find the toilet ok,they do not provide enough light for the females here to do makeup,etc.So i have both in those areas. Leds for me to hit the hole,and cfls for the fairer sex when needed.I think the website i found for low cost led lighting is www.superbrightleds.com. I beleive the best and cheapestway to use them in a home would be to have a seperate dedicated 12volt dc line feeding them,and use the 12volt dc leds made for automobiles in places like closets,hallways bedrooms,bathrooms,etc. Even if you ran one line into every room in the house,and had a few leds in each room and hallways etc,they would give you enough light to get through the house safely,without needing to turn on the cfls unless reading or doing things that needed normal lights. Also, with a dedicated 12volt line, If the grid power goes down, you would be able to hook in a deep cycle battery to the 12 volt line,and still have lights throughout the house.Or use a small solar panel to recharge the battery,and use that all the time to power them.Leds do use an incredibly low amount of power,you could probably run 50 or more for 2 weeks off of one charge on a deep cycle battery. For instance, i bought a cheap set of solar powered led christmas lights half price,for $10.00. A string of 50 of them.The solar setup is wrong for them though,as it only has one aa 1.5 battery in it. Well, being made in china,someone at the light bulb factory forgot to tell someone at the solar panel factory that it takes 3 volts to light up that set of lights,lol.So i cut them loose from the solar panel and they have been hooked up to 2aa batteries,and remained bright for about 2 days. Here i am now,well into the second week with all 50 bulbs still glowing dimly powered by only 2 aa batteries.You can cut apart the 110v led christmas light sets,and wire the bulbs in series groups of 3-4 bulbs and run them off of 12 vdc.Leds are great,if you dont need a lot of light.cfls are great,put out a lot of light,dont cost much,but can not be turned off and on repeatedly and expected to last as long as the package says.so, for some quick rough math, an 18 wattcfl costs about $4.00 new,and, if left on continuously,costs less than $20 per year to run,figured at 10 cents per kwh.A 100 watt standard incandecent bulb will cost you about $1.00 and $88 a year to run.most leds outputs are rated in lumens,1600 lumins equals about what a 100 watt lightbulb puts out. 1600 lumens worth of led lights would cost you several hundred dollars up front just for the bulbs,and probably emit a somewhat strange color of light.So,overall, the best deal for useable light is the cfl's. It would probably take 10-20 years to recoup the costs of led lighting through electric savings,as opposed to running cfl's that pay for themselves in a matter of months.Right now,my cheapest source of led lighting comes from led flashlights,run off of a small wall transformer that i grab at fleamarkets for 50cents. The flashlights cost 3-$10, and have between 9 and 20 led bulbs in them.And give me plenty of light in the basement,closets and bathrooms,for a guy anyway.The best one i have found yet has 20 led bulbs,runs on 4.5 volts,and costs $9.99 at right aid drug stores.It puts out maybe 15-20 normal watts worth of light.

LED: (Light Emitting Diode)

They emit way less heat than incandescent lights and some what less heat than fluorescents . The light intensity that is emitted can be adjusted by the amount of current that is applied and with some varieties this can also include a change of color. Unfortunately the voltage and currents source will need to be regulated to match your LEDs needs but if done properly that should be the only disadvantage, proper current management will ensure a long life and that will offset the costs. On the plus side the low heat dissipation will allow you to place them almost anywhere you can run the wires.

Additionally, healing of the wounds under a fluorescent light is not the best option, since that light prevents scars heal normally. That light prevents healing.

all, thx so much for the informative guide...john m...yr details for each of the existing lights is an eye opener ...generally, one takes it for granted and just goes out to but the normal or energy saver or ??? without really looking at the details...i know i am like that but now, this has given me a different perspective of it all...

if i do install the LEDs, would i then need as many as i would for the normal lightings...do i then need a lighting expert to map it out for me...if yes, then appreciate if anyone knows where i can contact a lighting expert in malaysia....thx once again to all.

Hi Low,

One thing I did not see mentioned is the LED's loss of lumens.

From what I understand the typical LED losses a significant percentage of it lumen producing capacity in the first year. So, for example, if you placed a set of LED's producing the equivalent light of a 100 watt bulb in your kitchen today, in a year you would have the equivalency of about a 60 watt bulb.

hi guest...that is interesting...did not think that it would lose that much...does it then mean i will have change out every couple of years....then it could be expensive. BTW, does it continue to lose its lumens even after the first year? thx.

Hi guys. It loses the lumens mostly as a result of a phenomenon called LED droop, which is related more to how highly powered the LED is than anything else. So, two factors to note (and I'm sure I'll be corrected if I get this wrong, which I probably have, in some point. So fire away, any of you who know about the problem.) are that the droop can be largely eliminated by proper control design, as noted earlier. The droop is a function, if I understand it correctly, of heating of the LED due to excessive power out requirements. Second, unless you so grossly overpower the LED that you fry it, the droop occurs, stabilizes, and doesn't get any worse. So, the 60% (the figure I've read) of residual lumen-producing capacity, assuming you don't just flat out fry the LED, is the bottom number it will drop to.

I suppose if you do your area lighting budget to take that into account, and can live with the overbright results until the droop stabilizes, you probably could just design the issue away, and only do one installation. Otherwise, I guess you could design with gaps in the lighting to be filled later once the droop has stabilized, using one or more additional phases of installation until it all settled in where you wanted it for the long run.

Micah

In a race to get the greatest short term brightness and lowest cost many of the new entrants to the LED lighting business push the lights past their safe operating envelope.

This is a combination of excess current and bad cooling.

you want it to run for 100 years? design from those areas.

an article on the problem

http://www.ledsmagazine.com/features/6/10/5

Good source here.

http://www.ledsmagazine.com/

Aurizon,

I appreciated the reference and your input. This thread has taught me also.

--JMM

Hi all, thx so much for the informative guide...definitely, it has given me a very quick course on LEDs and also other lights.....am still very interested to know if there is any recommendations for a good lighting expert in Malaysia that I could approach....

Just out of curiosity...is there a formula that can be used as guide for computing the savings...??

Thank you all, once again.