LED, Fluorescent, Incandescent?

[Dr. Trintignant]

Dr Trin,

The cheapest ones do rely on a string of low power LED's and would have a 60Hz flicker presumably. The one you have linked to looks like it has 5 1W LEDs (from CREE yeah!) But the latest and greatest are 3 and even 7 watt single LEDs operating at about 3.6V. I have a 3 watt LED flashlight running off 2 C cells and this thing could blind you if you looked right into it. The better flashlights actually use a DC-DC converter so that the light does not decrease rapidly as the batteries die, i.e. it keeps up the required volatage as long as it can.

IXP

I have a few nice LED flashlights as well using 1-3 W Luxeons or CREEs, powered from AAs or CR123s with a DC-DC converter. They are definitely nice as flashlights, but the color quality simply isn't there yet. Of course it's hard to use flashlights as a legitimate reference, since color perception in darkness is different than in bright light. But in any case the current crop of "white" LEDs just aren't there yet in my opinion. Hard to say whether they're better or worse than fluorescent, but even if they're a little better, that's not saying much.

One day I'll have to try building my own lighting system with a variety of LED colors. I make a little device with separate 1-W R, G, and B LEDs, but the white was still not very good.

- Dr. Trintignant

 

[kallsop]

You don't have to call a hazmat team if one breaks. There's less mercury than in a thermometer. A broom, dustpan, and plastic bag is enough. Just... don't handle the broken bits with bare hands.

When I went to school, we used to play with mercury in the science lab, bare hands, and guess what, no harm done. The miniscule amount in a fluorescent bulb is nothing to worry about, unless you eat the bulb.

I didn't break one yet, but when I do, I'll be picking it up with bare hands and putting it in the trash. There's a better chance of simultaneously getting hit by lightning while winning the lottery and juggling 4 balls in the air at once than getting harmed by the bulb.

 

[Lynx2174]

Meh, I already exclusively use fluorescent bulbs everywhere in my apartment. They were provided by the management. I'd use fluorescent bulbs anyway, because they're easier to find nowadays, and almost as cheap as incandescents, because they appear to be heavily subsidized around here. they've like a dollar or two each for the compact kind.

I'd switch to LEDs if they became similarly cheap, just because they're cool.

I don't care about color warmth or anything. Light is light to me. If I had any reason to do so, I'd be fine with living under sodium vapor lighting. If I want decent lighting, I'll get out of the house.

 

[casebro]

Don't fluorescents flicker at 60 hertz anyhow? And your computer screen at 24 fps. 40 should be harmless.

And I wonder about actually eating a compact fluorescent? Just exactly how many pounds of heavy metals are in one? Since the body can handle small amounts of heavy metals by exuding it in hair, how much can the body handle harmlessly? So don't eat the whole bulb at one sitting. And the overall environmental impact is nil, since the mercury came from the environment, we just use it for a while before returning it to the environment. It doesn't seem to hurt the swordfish...

And NOBODY has ever been harmed by mercury in commercial fish. There have been two cases of industrial pollution. One in Iraq, the people ate seed grain that had been treated with a mercury pesticide, the other was a Japanese sea-side village that got most of it's food from it's own bay- a bay that was polluted by the village's own industry.

 

[Dr. Trintignant]

Don't fluorescents flicker at 60 hertz anyhow? And your computer screen at 24 fps. 40 should be harmless.

Old-style fluorescents flicker at 120 Hz (since they light up in both directions) and can be a little annoying (though it's not too bad--the main problem is beat frequencies with other light sources). New-style (compact) fluorescents are much higher frequency--in the tens of kilohertz--and so don't have noticable flicker.

CRT monitors generally refresh at least at 60 Hz, and it's fairly unpleasant for some people (like me) to use them for long periods. 85 Hz or more is a minimum. LCDs (generally) don't have this problem.

Movies are at 24 frames per second, but generally each frame is flashed 3 times, for an effective refresh rate of 72 Hz. That's still not great, but much better than 24 Hz would be.

An LED lamp that had only a single string of LEDs would only light up once per cycle, or 60 Hz, and be pretty distracting for many people. I've seen some LED Christmas lights that worked that way and it was very noticeable.

Admittedly, some people don't have any problem with 60 Hz and don't even notice what's "wrong", but I'm pretty sensitive to it. I don't know exactly what frequency these LED taillights are at, but it's well under 60 Hz, and very distracting to me.

- Dr. Trintignant

 

[Philip]

I've got several burnt out compact fluorescent lights for which I didn't remember the installation date except to know they didn't last the five to seven years "guaranteed". I've started writing the installation date on the base of new bulbs I use so that I can take advantage of the guarantees. The packages indicate that the bulbs can't be used with dimmers or enclosed fixtures, so I can't use them in all of the fixtures in our apartment. Our kitchen has a long tube fluorescent fixture which provides the best light in the apartment. The color quality doesn't bother me. When I run out of replacement compact fluorescents, I might try some LED replacements if I can find some that are not too expensive. If I had my own house I'd make sure all the fixtures could take fluorescents or LEDs.

 

[Timothy]

Halogen lights simply suck. Too much heat and they burn out too quickly.

I have a sink/vanity alcove in my master bedroom that has a fixture with two halogen lamps. It's typically on a couple hours a day, with a lot of cycling. But it's on an electronic dimmer (press the switch and the lamps ramp to full output in about three seconds). This fixture has been there for nine years -- I've only had to replace each of the bulbs once in that time. Getting rid of the "instant on" switch works well with preserving the life of other incandescents in the house as well.

I also have several compact fluorescents in torchiere lamps. My major complaint is not flicker, but noise. They hum. Audible enough to destroy the silence of a room for reading, at least for me. Anyone else have this problem?

 

[Graham Jackman]

Old-style fluorescents flicker at 120 Hz (since they light up in both directions) and can be a little annoying (though it's not too bad--the main problem is beat frequencies with other light sources). New-style (compact) fluorescents are much higher frequency--in the tens of kilohertz--and so don't have noticable flicker.

CRT monitors generally refresh at least at 60 Hz, and it's fairly unpleasant for some people (like me) to use them for long periods. 85 Hz or more is a minimum. LCDs (generally) don't have this problem.

Movies are at 24 frames per second, but generally each frame is flashed 3 times, for an effective refresh rate of 72 Hz. That's still not great, but much better than 24 Hz would be.

An LED lamp that had only a single string of LEDs would only light up once per cycle, or 60 Hz, and be pretty distracting for many people. I've seen some LED Christmas lights that worked that way and it was very noticeable.

Admittedly, some people don't have any problem with 60 Hz and don't even notice what's "wrong", but I'm pretty sensitive to it. I don't know exactly what frequency these LED taillights are at, but it's well under 60 Hz, and very distracting to me.

- Dr. Trintignant

I've used the residual flicker to measure the rotational speed of centrifuges. recently, I looked at the degree of flicker from fluorescents and incandescents. There is less from the incandescents than standard fluorescents. but it is till measurable. it is interesting to note that at one time people would complain that their infrared remote controls didn't work at night. it turned out to be the the noise from compact fluorescents, which worked at a similar frequency. I find that the newer ones operate at a different frequency but the degree of flicker at the operating frequency is even stronger (in % terms) than standard fluorescents. I imagined that the phosphor would smooth out a lot of this.

 

[Soapy Sam]

In places (eg Scotland) where the main domestic use of electricity is for heating, the entire argument that tungsten and halogen lights "waste energy" as heat simply falls over. Heat is heat, regardless of the source.

By running 100W tungsten bulbs through the winter in my dark, Scottish, north facing flat, I not only make the place a lot more cheerful to be in , I also use exactly the same amount of energy to maintain an acceptable temperature as I would if I used low power fluorescents, but turned the heating up to compensate for the drop in "wasted" heat.

With tungsten bulbs, I also get bright light the second I switch it on, instead of five minutes later. Yes low power bulbs do brighten after a few minutes, but how often do we switch a light on for a few seconds to find something, then switch it off again? How wasteful is it if I have to leave a light on for five minutes before it's bright enough to see by?

In a slightly different context, I have been replacing low power (16W) tubes on my shared stair for several years. These remain switched on 24 /7. They reduce power consumption in that situation and provide adequate light, but they fade noticeably over a few months.
According to my ancient light meter, the light output from these tubes falls as much as 30% after six months and levels at about 50% of original brightness after a year. The tubes generally fail after 14-18 months constant use. They cost 10 times the price of a 40W tungsten bulb (£3.99 for the cheapest compared with £0.39 for a tungsten bulb) and the mounting fittings are also pricier than tungsten fittings.

So- there are advantages and drawbacks to both. We should fit the advantages to our requirements.

 

[El Greco]

So, the ideal light source:

1. Has low power consumption
2. Lasts a long time, even when frequently turned on and off
3. Provides instantly its full brightness
4. Doesn't flicker or make noise
5. Can be used with dimmers
6. Is relatively cheap to buy

 

[Soapy Sam]

Fireflies?

 

[Furi]

I thought most people here are enlightened enough to read by anyway

 

[Mr. Scott]

Movies are at 24 frames per second, but generally each frame is flashed 3 times, for an effective refresh rate of 72 Hz. That's still not great, but much better than 24 Hz would be.

- Dr. Trintignant

Almost all American theaters have projectors that flash each frame twice, so they flicker at 48 Hz. This is OK as long as the picture is not too bright and the screen is not wide enough to include peripheral vision.

American television on CRTs flickers at 60 Hz (30 Hz for fine details), which is fine most of the time, but European television (and film) runs at 50 Hz and drives me crazy, though the locals seem accustomed to it.

The flickering LEDs on automobile tail lights drive me crazy, too.

My house has florescent lamps almost exclusively. The cheap ones are bluish but light from the warm ones is indistinguishable from incandescent. I use the cheap bluish bulbs in the hallways.

As for longevity, keep in mind that the phosphors in florescent lamps and while LEDs dim gradually with use and may also loose their color balance.

 

[Furi]

Bizzare Delayed Double post..
*Spooky Music*

 

[Speedskater]

(snip)
On a related topic, is anyone else distracted by LED taillights on some cars (particularly some Cadillacs)? They can't be modulated at more than 40 Hz. They flicker horribly in my peripheral vision and break up into multiple afterimages (like a strobe light) when I shift my vision.

- Dr. Trintignant

Yes, some of the Cadillac's and more so the Infiniti FX series of SUV's. I first noticed this going down a long winding hill, with an old car between the Infiniti and me. The Infiniti looked like strobe lights jumping all over the road. On another automobile subject, all BMW headlights hurt my eyes. And Doctor I agree with just about everything that you have written a about home lighting.

 

[Cuddles]

Don't worry, they wont last that long!

IXP

I have to say, I'm always confused in threads like this when people comment on the lifetime of flourescent bulbs. When I was still living with my parents, we started switching to flourescent. Something like 15 years later, not a single one has died, while every single other light in the house has been replaced, usually more than once. Are some types of flourescent much worse than others, do some people buy really cheap bulbs that aren't worth the glass they're made from, or have my parents just been incredibly lucky?

I also have several compact fluorescents in torchiere lamps. My major complaint is not flicker, but noise. They hum. Audible enough to destroy the silence of a room for reading, at least for me. Anyone else have this problem?

Yes, I've notice the same. It's not a problem for normal lighting, but for things like bedside lamps that are close to your head and tend to only be used when it's quiet, it can be incredibly annoying. The Wiki page mentions that older style bulbs have a high-pitched hum, but the noise I get is not high at all.

 

[Dan O.]

There are places where the CF bulbs won't work well. The biggest killers are heat, cold and bad power. Many enclosed fixtures will get too hot for the electronics in a CF bulb and they will burn out early. If it's too cold most CFs won't light. Everyone expects that if the voltage is too high it will burn out the bulb quicker. But with CF bulbs it will also burn them out quicker if the voltage is too low because they have to pull more current.

BTW: Never use a CF bulb on a dimmer unless both the bulb and dimmer are designed for the task. It not only is bad for the bulb and bad for the dimmer but is a potential fire hazard because of the increased current.

I just watched a CF bulb die a couple of days ago possibly because it wasn't tight in the socket. It flickered a few times and before I could get up to check it the light went out and started smoking.

 

[fuelair]

P.S. Those who are choosing to go fluorescent, please describe how you're considering the hazardous nature of these bulbs in your decision. I think those arguments would be helpful to me in my decision. Thanks.

Basically, if the mercury was actually as dangerous as touted (it is if you drink it or breathe in a lot of it's fumes) it would really be a problem. But, I grew up in a world where chemistry teachers routinely demonstrated extraction of Hg from cinnabar by heating in open test tubes in open classrooms and had the students get close to observe it, Mercury was put in our hands to observe. Lot's of us "accidentally " broke thermometers to get mercury to coat pennies with - and just generally play with. Wildly, I can still think and write pretty clearly, My IQ has shown no signs of dropping, Nothing weird (like, say, heavy metal) has shown up in any medical tests. So.......
Safety is not a bad thing, I heartily advocate it. But, you need to consider at what level things might just be a bit over-reactive.

 

[Soapy Sam]

I shall say zis only vonce...


FLU (as in "over the cuckoo's nest) orescent.

(I just googled "flourescence". My god, can nobody spell this?)

 

[rcronk]

Great comments all! Thanks!

You don't have to call a hazmat team if one breaks. There's less mercury than in a thermometer. A broom, dustpan, and plastic bag is enough. Just... don't handle the broken bits with bare hands. It's not like dropping it on a rug is going to cause it to shatter, either. If that DOES happen, vacuum.
To get full life out of them, you HAVE to leave them on for AT LEAST 15 minutes at a time. Incandescents win out there - even compared with LEDs and halogens, making this bit of legislation very short-sighted.

According to the EPA, if a fluorescent bulb breaks:

Before Clean-up: Vent the Room

1. Open a window and leave the room for 15 minutes or more.
2. Shut off the central forced-air heating/air conditioning system, if you have one.

Clean-Up Steps for Hard Surfaces

1. <LI value=3>Carefully scoop up glass fragments and powder using stiff paper or cardboard and place them in a glass jar with metal lid (such as a canning jar) or in a sealed plastic bag.
2. Use sticky tape, such as duct tape, to pick up any remaining small glass fragments and powder.
3. Wipe the area clean with damp paper towels or disposable wet wipes and place them in the glass jar or plastic bag.
4. Do not use a vacuum or broom to clean up the broken bulb on hard surfaces.

Clean-up Steps for Carpeting or Rug

1. <LI value=3>Carefully pick up glass fragments and place them in a glass jar with metal lid (such as a canning jar) or in a sealed plastic bag.
2. Use sticky tape, such as duct tape, to pick up any remaining small glass fragments and powder.
3. If vacuuming is needed after all visible materials are removed, vacuum the area where the bulb was broken.
4. Remove the vacuum bag (or empty and wipe the canister), and put the bag or vacuum debris in a sealed plastic bag.
5. (From Maine's study: Suggesting that homeowners consider removal of the area of carpet where the breakage occurred as a precaution, particularly in homes with infants, small children or pregnant women

Disposal of Clean-up Materials

1. <LI value=7>Immediately place all cleanup materials outside the building in a trash container or outdoor protected area for the next normal trash.
2. Wash your hands after disposing of the jars or plastic bags containing clean-up materials.
3. Check with your local or state government about disposal requirements in your specific area. Some states prohibit such trash disposal and require that broken and unbroken mercury-containing bulbs be taken to a local recycling center.

Future Cleaning of Carpeting or Rug: Vent the Room During and After Vacuuming

1. <LI value=10>The next several times you vacuum, shut off the central forced-air heating/air conditioning system and open a window prior to vacuuming.
2. Keep the central heating/air conditioning system shut off and the window open for at least 15 minutes after vacuuming is completed.

Remove the carpet? You mean like cutting a hole in the middle of my room? I'm sorry, but that's just completely insane and I don't want this stuff around my kids - just in case. Maybe I'm overreacting, but I'll trust a scientific study (quoted above) before trusting anyone's suggestions.

[disclaimer]
I own stock in CREE, look it up.
[/disclaimer]

There is no doubt in my mind that LED's will dominate in 10 years. The combination of high efficiency, no toxic waste, and life that will exceed most humans is unbeatable by any other known technology.

Though the prices seem high today, they are not that bad when you take into account the useful life and lifetime energy savings, and this will improve.

IXP

So - what do you suggest for normal 65W incandescent equivalent LED home lighting? Is there something decent out there right now? If so, link to it. If not, when do you think it will be decent. Decent meaning good efficiency, long life, good price.

Fireflies?

Flaming cow pies.

Yes, some of the Cadillac's and more so the Infiniti FX series of SUV's. I first noticed this going down a long winding hill, with an old car between the Infiniti and me. The Infiniti looked like strobe lights jumping all over the road. On another automobile subject, all BMW headlights hurt my eyes. And Doctor I agree with just about everything that you have written a about home lighting.

I notice those but they don't drive me nuts. I wonder if this is more or less noticeable/annoying based on some biological difference between people?

I just watched a CF bulb die a couple of days ago possibly because it wasn't tight in the socket. It flickered a few times and before I could get up to check it the light went out and started smoking.

Smoking!? I guess it's probably not good to go sniffing that smoke up huh?