LED lightbulbs

[lmpower]

Have any of you tried LED lightbulbs? I am thinking about buying some. They are terribly expensive, but they last a long time and use very little electricity. They are environmentally friendly and contain no mercury. What do you think?

[Ralph]

Light the way and report back!

[Chalkperson]

[absinthe]

As long as you don't get misLED.

[BWV 1080]

Are they affordable yet? Can you get a quality white light? These are the two big problems. Current LEDs are at around 100 lumens per watt as opposed to 12 or so for an incandecent bulb or 60-70 a compact flourescent. The cost / benefit relative to compact fluorescent is probably not competitive yet

However, did you all notice the LED Christmas lights out this year at about twice the cost of ordinary lights?

[John F]

I'm looking forward to when LED bulbs are a good option to replace standard indoor lighting. As I understand it, they don't yet fill the bill. In the first place, they provide directional light, which makes them suitable for focused lighting (for reading, tasks, pictures, accents, flashlights) but not so great for room lighting. The other issue has been the quality of the light - a cold hard brightness such as you see in car LED headlights. Haven't seen any room that's actually lit by LED bulbs so maybe these problems are being solved or already have.

[lmpower]

Would you pay $39.95 for a light bulb?

Didn't think so. But what if it used 90% less electricity than a standard incandescent bulb, cut greenhouse gas emissions and saved you about $280 over its 25-year life span?

That's the challenge facing Dutch start-up Lemnis Lighting, which on Friday began selling the American version of what apparently is the world's first dimmable LED bulb compatible with home light fixtures.

LEDs -- light-emitting diodes -- are semiconductors that glow and are considered one of the great hopes for slashing carbon emissions from lighting, which consumes about 19% of energy production worldwide.

Lemnis says its Pharox60 LED lasts six times as long as an energy-efficient compact fluorescent light bulb. And unlike CFLs, LEDs don't contain toxic mercury.

Most often found in electronics equipment or in commercial lighting, LEDs tend to cast a cold light. Lemnis founder Warner Philips said the start-up spent considerable effort to engineer its 6-watt bulb to give off the warm white glow of a 60-watt incandescent.

"The final challenge is, how do you get people to understand that $40 for a light bulb is not expensive?" he said. "From Day One, they start to save money. The energy savings over the bulb's lifetime vastly exceed its cost."

Philips said one solution would be for utilities to finance the cost of swapping a home's incandescent bulbs for LEDs and add a fee to customers' monthly bills. The utilities would profit if lower electricity demand enables them to avoid the expense of building power plants, he said.

And that $39.95 price? That's a special offer -- the bulb retails for $49.95 -- good until Dec. 31. As production ramps up, Philips expects the price of the bulbs to fall.

[nut-job]

Would you pay $39.95 for a light bulb?

Didn't think so. But what if it used 90% less electricity than a standard incandescent bulb, cut greenhouse gas emissions and saved you about $280 over its 25-year life span?

That's the challenge facing Dutch start-up Lemnis Lighting, which on Friday began selling the American version of what apparently is the world's first dimmable LED bulb compatible with home light fixtures.

LEDs -- light-emitting diodes -- are semiconductors that glow and are considered one of the great hopes for slashing carbon emissions from lighting, which consumes about 19% of energy production worldwide.

Lemnis says its Pharox60 LED lasts six times as long as an energy-efficient compact fluorescent light bulb. And unlike CFLs, LEDs don't contain toxic mercury.

Most often found in electronics equipment or in commercial lighting, LEDs tend to cast a cold light. Lemnis founder Warner Philips said the start-up spent considerable effort to engineer its 6-watt bulb to give off the warm white glow of a 60-watt incandescent.

"The final challenge is, how do you get people to understand that $40 for a light bulb is not expensive?" he said. "From Day One, they start to save money. The energy savings over the bulb's lifetime vastly exceed its cost."

Philips said one solution would be for utilities to finance the cost of swapping a home's incandescent bulbs for LEDs and add a fee to customers' monthly bills. The utilities would profit if lower electricity demand enables them to avoid the expense of building power plants, he said.

And that $39.95 price? That's a special offer -- the bulb retails for $49.95 -- good until Dec. 31. As production ramps up, Philips expects the price of the bulbs to fall.

The price is absurd. Calculating price savings for a light bulb over 25 years is ludicrous. After 1 year someone will be making an LED lamp which is much better than what is available now (solving the problem of "cold" light, etc) and nobody will want to use an obsolete bulb for 25 years. The other issue is that the impact of savings on electric lighting on the homes energy consumption is not large, other things in the home consume electricity and even if you eliminated all lighting costs your electric bill will not go down by a dramatic amount.

I have switched over to compact fluorescent bulbs almost entirely. They pay for themselves over a time interval for which I can actually expect to use them. And despite complaints that they are "cold" I prefer the whiter light and I like the fact that they generate little excess heat. It is inevitable that LEDs will replace them, but not for $50 a pop.

[lmpower]

Nut-job's observations are well taken. He didn't mention the mercury content of CFL bulbs though. I would still like to test these even though the price should come down. I see some being sold for $100. That really is an absurd price.

[John F]

what if it used 90% less electricity than a standard incandescent bulb

Actually, only the 6-watt LED bulb is that efficient. The 5-watt bulb's max is the equivalent of a 40-watt incandescent. It says so on the Lemnis web site.

Either of these is a lot more efficient than compact fluorescent bulbs, which need more than twice as many watts to match 40- and 60-watt incandescents, according to the EnergyStar web site. How much difference this would make in a home electricity bill, I wouldn't know how to figure, but considering that refrigerators, stoves, TV sets, air conditioners, etc. etc. are also chewing up the kilowatts, lighting may be a fairly small part of the total. Still, every little bit helps.

Problem is, I've no use for 60-watt bulbs. The smallest ones I use at home are 75 watts, in an array of 3 across the top of the bathroom mirror. For lighting fixtures and reading lamps, even 100 watts isn't enough for me, and I mostly use 150-watt bulbs (actually, their equivalent in compact fluorescents, which range from 30 to 52 watts).

When I can get LED bulbs that are bright enough, give out a quality of light suitable for indoors, and are competitively priced with compact fluorescents, then I'd be happy to be a customer. But if Lemnis's product is the state of the art as of today, it looks like I'll have to wait quite a while.

[jbuck919]

I'd invite our posters to comment on what was common wisdom when I was a kid, i.e., is there any truth to the notion that incandescent bulbs could already be made to last for many years but aren't because nobody could make money selling something that didn't have to be replaced in 25 years? As I understand it there are (or were until relatively recently) Edison-era incandescent bulbs still burning in a few places.

The concept of a limited-life bulb was supposedly a variation of something called "planned obsolescence."

[lmpower]

Yes, jbuck, I have seen long life incandescent bulbs advertised. John F, I have just ordered some 13 watt LED bulbs, which give the equivalent of a 100 watt incandescent light. I hope to report back on the results within a couple of weeks.

[nut-job]

I'd invite our posters to comment on what was common wisdom when I was a kid, i.e., is there any truth to the notion that incandescent bulbs could already be made to last for many years but aren't because nobody could make money selling something that didn't have to be replaced in 25 years? As I understand it there are (or were until relatively recently) Edison-era incandescent bulbs still burning in a few places.

The concept of a limited-life bulb was supposedly a variation of something called "planned obsolescence."

An incandescent lamp gives what is called a "thermal spectrum" of light. For the light to be reasonably white the temperature has to be very high. You can make a bulb last a lot longer by running cooler, but then it will give a redish color (like when you use a dimmer switch). Deterioration of the filament occurs by chemical reactions which are related to the gas in the bulb. By filling with an inert gas like argon the life could be extended, but the life extension might not be worth the extra cost.

Given how easy it is to manufacture light bulbs it is hard to image that someone would not set up a company to make long life bulbs if it were technically and economically feasible.

[John F]

If long-life incandescent bulbs were technically and economically feasible, we'd surely have long since seen them competing successfully with standard bulbs. nut-job's explanation makes sense to me.

[lmpower]

Gentlemen, I have received a half dozen LED bulbs and am currently testing them. You are right about directionality. I have placed them in ceiling fixtures with a reflecting backgound. This seems to diffuse the light fairly well. I did not tell my other family members about what I did. My wife came home last night and cooked dinner without comment. Neither of my sons commented on anything wrong with the light. This is probably a better testimonial than anything one could get. I hope to report back on the impact on my electric consumption in a few weeks. I don't expect anything sensational, but I do hope to see a difference. Even if there is little or no financial benefit, I feel that I have done the ethical thing.

[lmpower]

I still use an incandescent light for reading. You can't beat them for quality of the light. They are being banned in Europe. A German man bought 3000 of them in order to have a lifetime supply. I forgot to mention that the LED bulbs emit a humming sound. It isn't loud enough to be a nuisance, but it did spook me a little when I first heard it.

[Mark Harwood]

Earlier this year a team at Cambridge University devised a way of manufacturing good white LEDs at an economic price. They might well be the way forward, unless one of the many other lighting technologies makes a leap. Many people don't like fluorescents, but they might improve too: the UV & the flicker may be overcome. Cyclists have a wide range of choices now, but there's something unsatisfactory about LEDs despite their low consumption & long life. As they develop, LEDs look like the best bet in the short/medium term; meanwhile, lots of us in cooler climes are stocking up on incandescents, because the heat they produce is not entirely wasted like the common efficiency figures assume it to be, and the light is "warm".

[lmpower]

Speaking of unsatisfactory LED bulbs, my wife just remarked that the kitchen light seems dim at times. I still haven't told anyone that I've changed to a different type of bulb. I don't think people would be happy with nothing but LED bulbs. Each type of bulb has its own advantages and disadvantages.