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Screw-in LED Floodlights

Anonymous Coward writes "This company claims to have the first LED flood lights that you simply screw in as a replacement for your old bulb. enluxled.com are also claiming it's cool enough to handle, more damage resistant, longer lasting (50,000 hours) and only uses 22w to produce twice the light of a 100w bulb." And hideously expensive, but you never have to change them.

49 of 573 comments (clear)

  1. How does this compare to... by Anonymous Coward · · Score: 5, Insightful

    Energy saving bulbs we have today?

    They only compare them against normal bulbs, and not energy bulbs, wonder why, not nearly as much good marketing maybe :D

    1. Re:How does this compare to... by AnotherBlackHat · · Score: 5, Informative

      It's been a while, but I think most of the numbers are still correct;

      Lumens/Watt Light Source
      100-190 low pressure Sodium (HID)
      (150 90W low pressure sodium lamp, clear)
      50-150 High pressure Sodium (HID)
      (115 1000W dual arc-tube high pressure sodium lamp, clear)
      100 Sylvania 18 watt low pressure sodium
      84 32W, 48" MOL, T8 OCTRON fluorescent lamp,
      60-65 standard F40T12 cool white fluorescent
      64 250W mogul based metal halide lamp, clear
      60 150W single ended compact metal halide lamp
      48-60 compact fluorescents
      45-55 Super bright Red/Orange LED
      35-45 Super bright Green LED
      17.5 Tungsten Halogen Single-End SUPER-Q Frosted Finish D.C. Bay 100Watt
      17.5 100W Incandescent A19 Bulb, softwhite
      14.5 60W Incandescent A19 Bulb, softwhite (standard bulb)
      6 incandescent night light bulb (7w)
      6w incandescent flashlight bulbs

      For normal home lighting T8 fluorescents are probably your best bet today.
      LEDs are good when you're want colored light, when you want a small amount of light, or when the cost/hassle of replacing the bulb is the major factor.

      Cree recently announced a 75 lumens per watt white LED, but AFAIK they aren't available in quantity yet.
      There's a lot of hope for the future of LEDs, but they're still a few years off.

      -- should you believe authority without question?

    2. Re:How does this compare to... by Dun+Malg · · Score: 5, Funny
      using the exact same process as flourescent lights

      Is that some process where they coat the inside of the bulb with ground wheat?

      it's fluorescent.

      --
      If a job's not worth doing, it's not worth doing right.
    3. Re:How does this compare to... by flyingsquid · · Score: 4, Interesting

      A fun thing about how cool compact flourescents are is that you can make paper lampshades (I like to use a good drawing paper, Japanese rice paper, parchment, whatever) and they don't get hot enough to be dangerous. A bit of origami skill and you can make some stylin' lampshades which look weird either lit internally or with the light off.

  2. Re:And you by The+Cisco+Kid · · Score: 3, Insightful

    Floodlights (eg the ones you put under the eaves of your house, often with motion sensors, to discourage burglars), not foglights (eg the annoying things that people turn on even when its not foggy), or off-road driving lights (eg, the annoying things that many people seem to think are safe and legal to operate on-road).

  3. it's about time... by buzban · · Score: 4, Interesting

    boy, this took a while to surface, given that LEDs have been so popular in automobiles, traffic lights, and railroad signals for the past few years...will have to give one a shot.

    1. Re:it's about time... by fossa · · Score: 4, Informative

      Traffic lights, for example, are owned by a city. The city keeps accurate budget information about how its money is spent. Incandescent traffice lights are typically changed on a yearly basis and require a substantial workforce with trucks and ladders to reach the bulbs. One can usually make a convincing case to a city that using LED traffice lights will save $x per year, and so the city opts to use LED lights.

      I personally do not keep track of my light bulb spending, and I imagine most households also do not. Thus the "it saves money in the long run" is a much more difficult argument to make.

      Furthermore, making white LEDs is typically done either with a blue LED surrounded by something that will emit yellow (and transmit some of the blue) when the blue LED is lit, or by using a red, green, and blue LED together.

      The first style has makes a white light that isn't "nice", because it's creating "white" by only combining two colors in the spectrum (blue and yellow). I can't explain it more than that, perhaps someone more knowledgeable can? This style is great for outdoor lighting (street lamps) where "niceness" doesn't matter so much; people aren't trying to read a newspaper but are merely identifying oncoming traffic.

      The second style is great (well, as good as RGB monitors), except for one problem: the different colored LEDs wear out at different rates. Thus the color of the light will drift slowly over time and obtain a green hue (how much time? I don't know... 2 years? 5 years?). So, the LEDs may last forever, but the "whiteness" may not last much longer than a conventional bulb.

      An aside: what is really cool about the tri-color LEDs is that you could potentially have dials to adjust the relative intensity of the colors and thus produce any color of the rainbow (or RGB spectrum at least), leading to many decorative and even utilitarian applications (e.g. a light inside a water faucet that lights the water according to its temperature).

    2. Re:it's about time... by Jeremi · · Score: 4, Interesting
      An aside: what is really cool about the tri-color LEDs is that you could potentially have dials to adjust the relative intensity of the colors and thus produce any color of the rainbow


      The suggests a potential solution to the color-shift problem: add some circuitry to the light that compensates for the color shift by dimming the other colors as necessary to maintain a balance.

      --


      I don't care if it's 90,000 hectares. That lake was not my doing.
  4. LED's are definately the future ... by xmas2003 · · Score: 3, Interesting

    LED's are definately the way to go, but the price still needs to come down quite a bit. People ask me if I used LED's for my Christmas Lights since when you have 22,000 of 'em (as I did in 2002), that's a lotta electricity. So while there are some GREAT looking LED Christmas Lights (with all the obvious advantages - and don't forget the color stays fairly permanent unlike painted on mini's), they are still really pricey ... especially when I can buy lights after the Holidays at 75% off.

    --
    Hulk SMASH Celiac Disease
  5. How many geeks.... by WesG · · Score: 5, Funny

    ....does it take to screw in an LED bulb?

    yay :-)

    1. Re:How many geeks.... by Anonymous Coward · · Score: 5, Funny

      Only two. But they'd have to be very small geeks to fit in the bulb.

  6. Re:forever by Ajmuller · · Score: 3, Informative

    no, it's just 5 years of continuious operation.
    Assuming that you use it for 5 hours a week (i would like to put this in to replace the floodlights in my backyard which are mounted high on the house and need to be replaced every year or so) it would last for 192 years. That's pretty much forever, at least long enough so my children and their children won't need to replace the bulb.

  7. Amish Lights by mordors9 · · Score: 4, Informative

    I live in the middle of an Amish community. I know that LED has been growing amongst them as a lighting source. An LED table lamp powered by batteries is becoming quite common replacing the hot, noisy and potentially dangerous gas lights that have been used in the past.

    1. Re:Amish Lights by Coopa · · Score: 3, Funny

      I thought Amish people didn't use technology, since when are LEDs not technology?

    2. Re:Amish Lights by mordors9 · · Score: 5, Interesting

      Actually they have a complicated set of rules that varies from area to area. Some areas they are allowed to have rubber tires, some areas not. In our area they have lots of wood shops that used gas powered air compressors. Then they use air tools for their work. One of the most interesting things I saw when I first moved to the area was an Amishman backing his horse and buggy up to a public boat ramp on a lake. He had a trailer with a boat and a Honda motor on it. Alot of them have phones outside in what appears to be an outhouse. Several households will share the one phone. But they can not be in their homes. The list goes on.

    3. Re:Amish Lights by MrResistor · · Score: 5, Interesting

      They aren't Luddites, they just feel it's spiritually important to keep things simple, and not get so caught up in modern consumerism that they forget what's important.

      IIRC, they have a counsel of sorts to deal with things like this, where something comes along that is so much better and safer, but no more complicated, comes along. Having grown up off-grid, and having plenty of experience with kerosene lamps and candles, I can definately appreciate where these guys are coming from.

      --
      Under capitalism man exploits man. Under communism it's the other way around.
  8. Never have to change them? by Antony-Kyre · · Score: 4, Insightful

    No, I did the math, and it would have to be changed every 5-6 years. 50,000 hours is approximately 2083 days. 2083 days is about 5.7 years. So running one 24/7, and yes, some people seriously do that, I'd have to buy one every 6 years.

    I realize how stupid this comment is, but just felt like pointing it out since the story did say, "but you never have to change them.".

    1. Re:Never have to change them? by kevinmf · · Score: 3, Interesting

      Ok - they are guaranteed for 50,000 hours. That doesn't necessarily mean that they'll die right then, though.
      A friend of mine has a company that makes LED products, and she says that they don't die at 50,000 hours, she just didn't want to guarantee them any longer than that becuase after that, it's not really cost effective. Granted, they might not last THAT much longer after that period, but still, it's awhile.
      Not to mention the fact that when LED lights die, they don't turn entirely dark, they just get a little dimmer as parts of them stop working, but other parts continue to function.

  9. Re:forever by 1010011010 · · Score: 5, Interesting

    50,000 hours isn't forever...

    No, but it is 5.7 years ($14/year) of continuous light, or 17 years $4.7/year) of eight-hours-a-day light.

    You can buy about 32 regular flood lamps for $80. They will last about 2,000 hours each. That's 64,000 hours total -- an additional $14,000 hours.

    So for home use, don't bother. For commercial or industrial settings, though, there can be lots of lights, and here is a labor cost associated with changing them. Some organizations change every light at once, to avoid the higher cost of replacing bulbs individually as they burn out. For those types of applications, the longer-lasting LED lights will lower the cost of changing bulbs.

    --
    Napster-to-go says "Fill and refill your compatible MP3 player", which is a lie. It's not MP3. It's WMA with DRM.
  10. What a dilema for students by Timesprout · · Score: 5, Funny

    Be cool, trendy and enviromentally friendly like students want to be and get these leds at the price of a weeks drinking money per bulb and also the loss the main heat source in their house.

    --
    Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
    What truth?
    There is no dupe
  11. The Savings by Anonymous Coward · · Score: 5, Informative
    Using their calculator. (One bulb)
    • Current annual electricity costs: $5.69
    • Current bulb life: 20.5 months
    • Current annual replacement bulb costs: $1.76
    • Current maintenance hours per year: 0 hours
    • Current annual maintenance costs: $0
    • Current annual lighting costs: $7.45
    • Enlux LED Flood unit cost: $80
    • Enlux LED Flood wattage: 22W
    • Annual electricity costs with Enlux LED: $1.93
    • Enlux LED Flood life: 50,000 hours or 411 months when used for 4 hours per day
    • Months until break even point: 167 months
    • Total savings with the Enlux LED Flood: $112.06
    1. Re:The Savings by GoRK · · Score: 4, Insightful

      Also keep in mind that their calculator does not figure the time-value of money into the equation at all. If you plan on doing anything better with your cash than investing in LED lighting products, the break even will NEVER, EVER happen -- at least for a homeowner.

      LED bulbs are making a bit more business sense in certain commercial installations where you actually have to pay a human being a minimum feee for an hour or so of labor to go replace a few lightbulbs. Especially in situations where the bulbs are so difficult to reach that it takes a few hours to actually change them and causes an inconveneince for other people while they are being changed -- the fee to change a bulb could easily outstretch the cost of LED lighting. Often in situations where 'expensive' bulb changes happen, they will change all the bulbs at the same time even if they don't need it simply because all the rigging and labor will be there and ready to go.

  12. they are not 200 watt equivalents by planetary+gear · · Score: 4, Informative

    They come in 45 watt and 65 watt equivalent bulbs, not twice the output of a 100 watt bulb as stated in the article ;) At this moment a CF bulb can be more efficient than them, pulling as little as 14 watts to produce the same output they do at 22. Tubular fluorescent bulbs are even more efficient. They do look cool though, and LED's get better and more efficient every year. At a watt or 2 there is nothing that can touch an LED as far as efficiency, but as soon as you go to higher power levels then even a halogen bulb can be more efficient. In my 1AA flashlights nothing is better than an LED. Plugged into the wall you're better off with a CF bulb.

  13. Re:flourescent bulbs by Ironsides · · Score: 5, Informative

    Reasons for using LED over Flourescent:
    1) When a flourescent bulb fails, it stops giving off light completely. Usually and LED light will only have 1 led fail at a time. Given theis, you don't have large areas of darkness and don't have to replace the bulb immediatley when a part fails. LEDs fail gracefully.

    2) LEDs are more resistant to damage.

    3) The LEDs appear to not need to be replaced as often as Flourescent. The largest "Pain" in lighting is having to replace the bulbs. If these new LEDs last sufficiently longer than Flourescnets, they pay for themselves in labor.

    4) I'm not sure about this, but I don't think I've seend flourescent spot lights before. However, the LEDs might be able to put out more light than flourescents.

    --
    Fly me to the moon Let me sing among those stars Let me see what spring is like On jupiter and mars
  14. Does NOT generate 100 watts of light with 22 by augustz · · Score: 5, Informative

    THIS IS NOT TRUE!!

    The specs for the light are I beleive 300 lumens. This is more like a 45-60 watt bulb.

    A 100 watt bulb might generate 1500+ lumens.

    It still is significantly more efficient, and with a SIGNIFICANTLY longer life span, but it is not equal to a 100 watt bulb.

    When these first came out (won some awards) I checked them out for this very thing.

    They also are not an all around type light a la a lightbulb, more of a spotlight (90 degree beam angle?), so better for flooding a wall or artwork with color / light.

    Still super cool. Still a bit expensive.

  15. How is 1/5 the lumens equivalent? by fmaxwell · · Score: 3, Informative

    According to the GE web site, their regular old 90W floodlight produces 1,100 lumens. Move up to a halogen 100W from Sylvania, and you're at 1,500 watts. From what I saw on the Enluxed web site, their 22w (nominal) LED floodlights produce 300 lumens.

    I'm a big fan of LED lighting (having bought three LED flashlights last night as presents), but this is just absurd -- unless there is some kind of misprint or my reading comprehension is not up to par today.

    1. Re:How is 1/5 the lumens equivalent? by mrfantasy · · Score: 4, Insightful

      if you read closely, the claim that the lights put out twice the light output of a 100w flood only applies to the COLORED floodlights.

      Which makes sense. A red LED floodlight will be made only with red LEDs, which emit nearly all their light in the red part of the spectrum. a 100w incandescent red floodlight is a regular incandescent with a red filter on the glass, which absorbs most of the light. The implication is that a 100w colored floodlight puts out about 150 lumens. I can believe that.

      --

      -- Of course I'm paranoid. I'm a sysadmin.

  16. Re:flourescent bulbs by TheApocalypse · · Score: 3, Informative
    Because standard fluorescents aren't dimmable. I work in an auditorium and we have regularly dicussed how great it would be to have LED flood lights in the house lights. They do make dimmable fluorescents, but they are very expensive and don't have a "natrual" look that standard halogen lamps do.

    And since we have to walk on a 40' high plaster ceiling that is 40 years old, the lesser trips we make to change house lights, the better it is, no matter what the cost may be.

  17. Re:forever by canavan · · Score: 4, Insightful

    You're comparing just the cost of the bulb itsself and the installation, ist your electricity free?

    Over here, the LED bulb (assuming the 20W instead of 100W incandescant) would save 50000*(100-20) Wh = 4000kWh at more than 10c each - that's at least $400 saved over the lifespan of a single bulb.

  18. Not much better than flourescent... by david.given · · Score: 3, Interesting
    The site's slashdotted, so I can't actually go and see what they've got, but I know that in the past white LEDs had problems because they don't do white very well. I wonder if they've managed to solve them...

    Flourescent lamps work by using a mercury vapour discharge tube to produce ultraviolet light, which excites a phosphor coated on the inside of the tube to produce white light of various colours. They work pretty well; my house pretty much only uses 22W flourescent bulbs, which are roughly equivalent to 100W incandescents. The colour's not bad, but the spectrum is a bit weird, and some things look a little strange. (My parents have a glass vase that shows up purple under sunlight or incandescent light, but green under flourescent light.)

    White LEDs can use the same system, with a UV LED that excites phosphor, but these are inefficient and very expensive. (Or at least were, the last time I looked.) A more common way is to use a red, green and blue LED in the same package. These can be cool because you can change the colour by simply changing the relative brightnesses, but they produce a spectrum that makes flourescent tubes look normal. Compared to incandescents, they're very blue, and some things look really strange.

    Does anyone actually know what these things are?

  19. Motion Lights by Fone626 · · Score: 3, Funny

    I've got flood lights on motion sensors. The idea is to drive off the theives from stealing stuff around my house.
    With these LED lights my stuff would be further protected by having the light itself worth more than anything else lying around worth stealing.
    Hmmm, maybe I should get motion lights for my motion lights.

  20. Re:forever by NeoSkandranon · · Score: 5, Funny

    shoot a couple kids with slingshots and that problem will go away.

    --
    If you can't see the value in jet powered ants you should turn in your nerd card. - Dunbal (464142)
  21. Re:And you by jhobbs · · Score: 4, Funny
    -snip-
    retrovisor.
    -snip-

    What an incredibly cool word! And to think that as an American I am stuck looking at my rearview mirror.

    Spock, bring up the image in the retrovisor!

  22. Re:And you-Lite-Brite. by Anonymous Coward · · Score: 4, Insightful

    There are such laws. Not everybody follows them. A lot of the halogen bulbs, though, are still under the max.

  23. Fluorescent bulbs are already annoying enough by Twid · · Score: 3, Informative

    Is anyone else annoyed by the trend by hotels with replacing EVERY bulb in a room with compact fluorescents? One hotel I was at recently (the Boston Westin) did this, and I've seen a trend towards this more and more. With every light in the room on, it was still a bit dim and uncomfortable to read a book on the bed. Pretty annoying. It seems like much of the savings of fluorescent and other "cost saving" bulbs are from dimming the lumens of output.

    Given that these LED bulbs are dimmer than a normal one too, the savings seem questionable. It's like saying that you can double your gas mileage in a new car assuming you drive it half as much.

    --
    - "When you want something with all your heart, the entire universe conspires to give it to you" -Paulo Coelho
  24. How long has it been... by gaijin99 · · Score: 3, Informative
    Your information seems to be badly out of date. The early model compact florescent bulbs did make a really hidious color light, but not any more. I use compact florescent light exclusively at my house. Since about two years ago they have made nice natural color bulbs. Meantime, my electric bill has gone down by about $5-$8 a month and I haven't changed a bulb in about two years. Overall I'm quite happy with my compact florescent bulbs.

    --
    "Mission Accomplished" -- George W. Bush May 1, 2003
  25. NOT the first. by outanowhere · · Score: 5, Interesting

    "This company (enlux) claims to have the first LED flood lights that you simply screw in as a replacement for your old bulb. "

    This claim is false.

    Commercial white LED floods and other replacements for high-voltage incandescent bulbs are available for any standard base in the world, including the funky euro and russian bases. They are available at three colour temperatures and in any other LED colour, including IR and UV.

    They have been available for more than two years.

    Enlux had no such products available a year ago.

    Seems they define "flood" a bit broadly: According to their own data, it illumines a narrow region like a spot would.

    50K hours seems a little short-lived.

    And white LEDS dim quite noticeably over a very short time. They will most likely be too dim long before 50K hours. Most likely in a bit less than half that time, around 20K hours.

    If they are willing to lie about being the first, and deceive about the useful life of their lights, what else will they lie or cheat on?

    Wonder if enlux will do for LEDs what Lights of America did for fluoros...

  26. living a simple life by chocolatetrumpet · · Score: 4, Interesting

    As the grandparent said, this "complex system of rules" is just religion oriented rule utilitarianism in action. The point is to live a simple, happy life in service of God.

    A story I once heard on the radio: some Amish people are outside doing their laundry by hand, as a group; laughing, playing, and having a grand old time.

    Meanwhile a person living a modern-lifestyle goes miserably jogging by. This person was not enjoying their jog, plus stressed out by a job that is used to buy expensive labor saving machines (washer/dryer) that STILL required time to load and operate.

    The Amish doing their laundry by hand were getting exercise and camaraderie, and as a bonus they got their laundry done all at the same time. They were also not involved in an time-consuming job to pay for expensive gadgets.

    See how it all works? Over time, the rule utilitarianism builds up to a happy life.

    Of all the things modern society has to offer, you might think that wandering a modern store the Amish would be most amused by modern electronic gadgets. This is not the case - the simple pleasures always win out. Check out any Amish people in a modern store and you will certainly find them, especially the children, trying out high sugar snacks and beverages.

    Pop - one of the most pleasurable modern amenities :-)

    --
    Spoon not. Fork, or fork not. There is no spoon.
    1. Re:living a simple life by ajayvb · · Score: 5, Insightful

      Awww....give me a break. Have you ever washed clothes by hand? I have. I lived in India, and when I lived in dorms during my engineering days, we had no laundry facilities. "Going home to do the laundry" acquires a totally new dimension then (My parents had a washing machine at home). Try wringing out a pair of jeans to dry on a cold morning at 40 F , and then we'll talk.

  27. Sulfur Microwave Lamps by lhaeh · · Score: 3, Interesting
    Sulfur Microwave Lamps are the most efficient light source, in terms of visable, white light.

    The article is really old, there have been major improvements since then, but it gives you a good idea of the basic principals of operation.

    I want to try makeing one of these, just put some sulfur and argon, both easy to get, into a glass tube. Toss it into the microwave and see what happens.

    1. Re:Sulfur Microwave Lamps by unfortunateson · · Score: 3, Informative

      Sulfur Microwave lamps have two major disadvantages:
      1) They're big, not designed for desk lamps and such
      2) They use a 2.45GHz microwave generator. That number should sound familiar.... yup, they jam 802.11b/g. For that reason alone, many government installations can not use WiFi.

      --
      Design for Use, not Construction!
  28. Comparison. by Ungrounded+Lightning · · Score: 4, Informative

    How does this compare to...Energy saving bulbs we have today?

    Power usage for a given amount of light is slightly better (22 vs 26 watts for a 100 watt equivalent).

    Life is a lot better. (50,000 hours vs. 6,000, or about 8 1/3 compact fluorescents to match rated lives with one LED lamp.)

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
    1. Re:Comparison. by uhoreg · · Score: 3, Insightful

      Actually, the summary says that the 22W LEDs produce twice the light of a 100W incandescent. So it's more that slightly better than compact fluorescent.

      --

      To get something done, a committee should consist of no more than three persons, two of them absent.

  29. Re:specs kinda suck by BP9 · · Score: 3, Interesting

    These aren't apparently any good for indoor area lighting (I have dozens of ceiling can lights I'd love to use such a thing in): per the website they cannot be installed in can's (temperature issues?) and cannot be dimmed (which leads me to wonder how you run them at 15W to get the rated lumen output rather than 22W as speced).

    No dimming is the reason I haven't switched to using excellent warm compact flouresecent lamps.

    Maybe they just stuck a resistor in series with a bunch of LED's and they're burning the other (large) chunk of power in heat. Nah... if they did that at least it would be dimmable. I wonder how they could make a PWM thing generate so much heat you can't use it in an enclosed fixture.

    Sigh.

  30. Light quality ? by dargaud · · Score: 4, Interesting
    I hope those provide better lighting quality than the so-called energy-saving bulbs. I just moved into a new appartment and decided to use those ESB. They are a scam IMO:
    • they absolutely are not '5 times brighter than normal bulbs'. The 100W equivalent lits about as much as the old 40W bulb that was there.
    • their color sucks, depending on the model (I bought several different), they are either greenish or even more yellow than a tungsten bulb
    • They take time to lit to full output.
    • They cost a lot.
    After a month of trying to get used to them, I threw them away. So I hope LEDs can do better, but since I already have several headlamps with while LEDs, I expect some problems. In particular the headlamps I have (Petzl and Black Diamond) are way too blue, they are blinding.

    So, technical issues or marketing issues ?

    --
    Non-Linux Penguins ?
  31. Re:I hope they are "warmer" than fluorescent lamps by jonbrewer · · Score: 3, Informative

    I wonder why they do not paint fluorescent tube with a yellowish hue to make them warmer. I bet if they would do this, they would conquer a greater market.

    Compact Fluorescent bulbs come in colour temperatures from 2700-6500K. Higher colour temperatures equal "cooler" light with more blue.

    Check these links for an explanation:

    * http://www.tvtechnology.com/features/Tech-Corner/f -rh-white.shtml
    * http://en.wikipedia.org/wiki/White

    I started using CF bulbs a few years ago simply b/c of the geek factor. I've found that quality varies and few remain bright throughout their entire useful life. Some run hotter than others. Also found that different rooms / applications call for different colours. YMMV.

  32. Re:flourescent bulbs by clambake · · Score: 3, Funny

    1) When a flourescent bulb fails, it stops giving off light completely. Usually and LED light will only have 1 led fail at a time. Given theis, you don't have large areas of darkness and don't have to replace the bulb immediatley when a part fails. LEDs fail gracefully.


    I finally understand the doom 3 lighting scheme...

  33. Re:forever by rco3 · · Score: 4, Informative

    Let's bring a bit more factuality to the situation: The parent poster states that heat pumps are cool technology, and that radiant electrical (resistive strip) heating is inefficient.

    Guess what? Parent is correct.

    Radiant (resistive strip) heating is LESS efficient than a heat pump under many circumstances. "What? No, stupid - radiant strips are 100% efficient! All the power is converted directly to heat!" Yes, it is - but I'm not stupid. Heat pumps are more efficient. Typically, with an outdoor temp of 45F an an indoor temp of 72F, the heat pump moves THREE TIMES as much heat into your fine home as it requires electricity to perform the pumping. IOW, 100W of energy into the heat pump results in 300W of heat into the house. That's three times more efficient than strip heating.

    This is not as pronounced at greater temp differentials, and in fact many heat pumps employ supplementary strip heating for really large temp extremes. However, the parent poster's point is well-made and accurate - radiant strip heating IS, in general, less efficient than a heat pump.

    I live in Florida - north Florida. It's November 21, and my A/C is on. Every watt I save from running fluourescent or LED lighting is effectively 1.3 to 1.5 watts less electricity used and charged on my power bill. A similar argument can be made for a house using a good heat pump - the extra wattage radiated as heat by an incandescent bulb would provide even more heat if it were used to drive a heat pump instead.

    --

    Ce n'est pas un vrai mouvement de robot!
  34. Re:Turn on Delay and Colour Rendering by Alioth · · Score: 3, Informative

    Actually - they aren't variable resistors, they are thyristor control. If you look at the size of a 1W resistor, imagine how big the resistor would have to be for 240VAC, 60W.

    The thyristor control basically chops off part of the AC wave form that arrives at your light bulb - so on dim, you have very very short pulses (so the tungsten filament doesn't get very hot, and therefore not very white) and as you turn the light up, the pulses get wider (until you reach full brightness, which is the normal AC waveform).