Energy saving lightbulbs --- any thoughts?

[90K]

Wow that was hugely informative post Karl; I think the work is on to widen the wave length of the LED. the reaction times for the automotive use is one of the reasons many auto manufactures are tending to make the brake lights in LED and in several different configurations even turn signals are used as well. The other thing like Karl mentioned it the ability of the LED to pierce the when activated.

 

[KarlMarx]

Wow that was hugely informative post Karl; I think the work is on to widen the wave length of the LED. the reaction times for the automotive use is one of the reasons many auto manufactures are tending to make the brake lights in LED and in several different configurations even turn signals are used as well. The other thing like Karl mentioned it the ability of the LED to pierce the when activated.

Thanks for the compliment. I'd like to add something to demonstrate the long life of LEDs. I bought a clock radio in March of 1982 (nearly 25 years ago). The clock radio has an LED display for the time. I still use it. The display has been on continuously for nearly the entire 25 years and it still works as well as it did when I took it out of the box in 1982. I've never had any parts replaced. That means that the LEDs in that display have been on continuously for nearly a quarter of a million hours and are still going strong. I don't think that even the Energizer Bunny can last that long.

 

[90K]

Thanks for the compliment. I'd like to add something to demonstrate the long life of LEDs. I bought a clock radio in March of 1982 (nearly 25 years ago). The clock radio has an LED display for the time. I still use it. The display has been on continuously for nearly the entire 25 years and it still works as well as it did when I took it out of the box in 1982. I've never had any parts replaced. That means that the LEDs in that display have been on continuously for nearly a quarter of a million hours and are still going strong. I don't think that even the Energizer Bunny can last that long.

But does the volume switch crackle when you mess with it? If it doesn't then you have a true gem....really and yes you made a good point on the LED numbers on the displays.

 

[Annie]

I am now on my 6th week with the new energy saving lights. I've noticed one minor difference. The energy saving lights will be dimmer initially, but after about 30 seconds, they are just as bright as a regular incandescent, perhaps even more so.

I've noticed a couple of really neat things about them. If you turn them off in a dark room, they have a very faint glow for about a minute. Another thing I noticed is that they will glow for a second if there is any static discharge nearby. The reason for both phenomena is that the inside of the tube is coated with a phosphor that glows in the presence of an electrical field.

One other thing. Since the energy saving light bulbs are actually fluorescent light bulbs, they contain a small amount of mercury. You aren't supposed to dispose of them in the trash.

The reason that both energy saving lights and LEDs are so energy efficient is that they use more of their energy than incandescents to create light instead of heat. In the case of LEDs, nearly 100% the energy is used to create light. Energy saving lights use an electrically charged gas to stimulate a phosphor that glows in the presence of an electrical field. LEDs give off light using quantum effects. An energy saving light uses about 14 watts to give off the same light as a 60 watt light bulb. An LED light uses about 5 or 6 watts to do the same. Because LEDs generate light using quantum effects, they can only radiate a single wavelength. That is why LEDs come in single colors. White LEDs do not actually radiate white light, they emit ultraviolet light, but their enclosures are coated with a phosphor that radiates white light in the presence of ultraviolet light.

Major cities that have switched to LED lighting for traffic signals have reported cost savings of over 1 million dollars a year because LED traffic signals use so little electricity. In addition, LEDs have very long service lives. LED lighting can have a service life of about 100,000 hours (that's about 11 years of continuous use).

I've noticed that LEDs seem to give off a great deal of light in one axis (straight ahead), but as you move away from that central axis, the intensity of the light diminishes. That is why LEDs are so good in signal lights and displays. In those applications, the viewer is usually on, or near, the central axis. However, LEDs are not as well suited for general lighting for precisely the same reason. Many LED lights simply consist of a flat array of LEDs. So they give off an intense light directly in front of them, but the light quickly becomes fainter as you move away from that central axis. I think the problem is how the LEDs are distributed in LED light bulbs. If someone could invent a way to arrange the LED semiconductors on a sphere, then enclose the sphere with a phosphor coated envelope, they may be onto something.

Well I'm nearly sold on buying some, question though. How are you supposed to 'dispose' of them, when they do wear out?

 

[KarlMarx]

Well I'm nearly sold on buying some, question though. How are you supposed to 'dispose' of them, when they do wear out?

I don't know. My guess is that you can take them to a local lighting or hardware store for disposal. I think that a definite answer to that question can be answered by your local public works department.

 

[Mr. P]

Thanks for the compliment. I'd like to add something to demonstrate the long life of LEDs. I bought a clock radio in March of 1982 (nearly 25 years ago). The clock radio has an LED display for the time. I still use it. The display has been on continuously for nearly the entire 25 years and it still works as well as it did when I took it out of the box in 1982. I've never had any parts replaced. That means that the LEDs in that display have been on continuously for nearly a quarter of a million hours and are still going strong. I don't think that even the Energizer Bunny can last that long.

Yep, mine was bought in 1980, still going..

 

[fuzzykitten99]

Well I'm nearly sold on buying some, question though. How are you supposed to 'dispose' of them, when they do wear out?

your trash collector can answer that as well. my trash is handled thru the city, which handles all our utilities, so i just called them, and they gave me lots of locations, including some stores that will take them for you at no charge.

 

[manu1959]

Has anyone purchased those energy saving lightbulbs? You've seen them, they look like little pigtails. I replaced all of my incandescents with them and they seem to work just fine...

yep have them everywhere...work great

 

[Greg Bernhardt]

Are these florecent? I need the warm yellow light since I live in WI.

 

[Annie]

Are these florecent? I need the warm yellow light since I live in WI.

Greg, ummm, cheese doesn't glow! (Go Bears!)

 

[Greg Bernhardt]

Greg, ummm, cheese doesn't glow! (Go Bears!)

Know wonder my apartment smells!

 

[Annie]

Know wonder my apartment smells!

 

[BaronVonBigmeat]

The great thing about newer fluorescents like this is, they come on instantly. None of that flickering crap. The light is slightly dim and reddish at first, but warms up to a nice pure white. You can't use them on a dimmer though.

I'm still looking forward to consumer-level LED lighting though. The switch to LED's from fluorescents will be nearly the same as the switch to fluorescents from regular incandescents.

Another thing...the electricity used by lighting is a fairly small percentage of your total energy bill, even if you use regular bulbs. I wouldn't bother changing out all my bulbs, stick to ones where it's on a lot and the bulbs are hard to reach and change out, like a high ceiling fan in the living room.

If you really want to save money, you'd be much better off spending money reducing the amount of A/C and heating you use, which is the biggest part of your bill. Two of the engineers in my office put a radiant barrier in their attic and swear by it. One of them said it cost him like...$275 for his whole attic, and he said you could easily feel a difference standing under the finished rows of barrier.

The electric companies run ads telling you to add insulation. Doesn't that seem a bit odd? Please install something that reduces demand for our product? Here's the deal: electric companies struggle to fill demand during the day, and have excess capacity at night. But you can't really just take a giant industrial turbine and shut it down for a few hours, from what I understand. So, they don't really want to reduce useage, they want to spread out the wild swings in demand.

That's what insulation does. To an extent, it saves money. Past that, you're just soaking up heat during the day to release at night. Your attic is still hot, and you're just slowing heat from entering your house. But a radiant barrier stops your attic from getting hot to begin with...which is probably why the electric companies don't mention it (or window films).

 

[glockmail]

.... Two of the engineers in my office put a radiant barrier in their attic and swear by it. ....

What's that?

 

[KarlMarx]

What's that?

http://www.ornl.gov/sci/roofs+walls/radiant/rb_02.html

 

[glockmail]

Experiments with various levels of conventional insulation show that the percentage reduction in ceiling heat flow due to the addition of a radiant barrier is larger with lower amounts of insulation. Since the fraction of the whole-house heating and cooling load that comes from the ceiling is larger when the amount of insulation is small, radiant barriers produce the most energy savings when used in combination with lower levels of insulation. Similarly, radiant barriers produce significantly less energy savings when used in combination with high levels of insulation.

The obvious question is, where is the break-even point between a radiant barrier and more insulation? I recently increased the insulation in my attic to R60 or so, and that was very cheap.