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LED Lighting As Cheap As CFLs Invented

Posted by Soulskill on from the bright-ideas dept.

mcgrew writes "New Scientist reports that a British team has overcome the obstacles to cheap LED lighting, and that LED lamps as cheap as CFLs will be on the market in five years. Quoting: 'Gallium nitride cannot be grown on silicon like other solid-state electronic components because it shrinks at twice the rate of silicon as it cools. Crystals of GaN must be grown at 1000C, so by the time a new LED made on silicon has cooled, it has already cracked, rendering the devices unusable. One solution is to grow the LEDs on sapphire, which shrinks and cools at much the same rate as GaN. But the expense is too great to be commercially competitive. Now Colin Humphreys's team at the University of Cambridge has discovered a simple solution to the shrinkage problem. They included layers of aluminium gallium nitride in their LED design... These LEDs can be grown on silicon as so many other electronics components are. ... A 15-centimetre silicon wafer costs just $15 and can accommodate 150,000 LEDs making the cost per unit tiny.'"

11 of 553 comments (clear)

  1. My first experience with LED lighting... by gfxguy · · Score: 4, Insightful

    So I bought a 3 pack of LED lights that were supposed to be the equivalent of 40 watt bulbs...

    A 25 watt incandescent bulb is about 10 times brighter. I was pissed. Might keep me from stumbling in the dark, but it doesn't really illuminate a damn thing.

    I was so hopeful.

    --
    Stupid sexy Flanders.
    1. Re:My first experience with LED lighting... by gnick · · Score: 4, Insightful

      I've heard similar reviews from a co-worker who was very motivated to 'go green'. The '40-watt equivalent' turned out to be an over-sized night-light (per her review - I haven't seen it).

      Still, this could be good news. I switched about half-way to CFLs largely to save $$ on electricity, but they're neither as efficient nor as 'green' as LED lights. I priced LED lights but, at the time, they were so damned expensive that it would take ~40 years for the investment to pay itself off. Even if I have to over-rate everything to get the same level of light, it should be better all the way around compared to the current alternatives.

      Still, even though this sounds solid, the ominous 'This should be available in 5 years' always makes me a little cautious.

      --
      He's getting rather old, but he's a good mouse.
    2. Re:My first experience with LED lighting... by rolfwind · · Score: 5, Insightful

      + disposing them is order of magnitude worse than conventional lightbulbs.

      Any home depot accepts any and all CFLs. In fact, it's easier and cheaper to dispose of CFLs properly than it is of Fluorescents.

      Oh, and if your electricity is generated from coal, you are helping put mercury in the air as well.

  2. Sweet by internerdj · · Score: 4, Insightful

    Except I've already switched most of my house to bulbs that last longer than incandescents. Maybe the flourescents will start burning out by the time I can get some good cheap LED bulbs.

  3. If they are still not dimmable they still suck by Lumpy · · Score: 4, Insightful

    Honestly we NEED a led light bulb that will DIM acceptably for people.

    most people want to be able to use dimmers and every customer I have wants to use lighting automation.

    They need to work on that second right after figuring out how to get the lumens up to that of CFL lamps.

    --
    Do not look at laser with remaining good eye.
  4. Re:What about the production? by Idiomatick · · Score: 4, Insightful

    If you only replace them at 1/10th or 1/1000th the rate then its unlikely it could be bad for the environment....

  5. Ahh, 5 years... by PowerVegetable · · Score: 5, Insightful

    The good ole' 5-year technology promise. Close enough to be exciting and get attention, but far enough away that you'll forget about their claim before they miss their deadline.

  6. you sir are incorrect by Chirs · · Score: 3, Insightful

    "Light Emitting Diodes are binary - either all the way on or all the way off"

    You're smoking crack. LEDs can be dimmed just fine, by varying the current going through them. How do you think they control the brightness in LED-backlit LCD displays.

    1. Re:you sir are incorrect by nwf · · Score: 4, Insightful

      You're smoking crack. LEDs can be dimmed just fine, by varying the current going through them. How do you think they control the brightness in LED-backlit LCD displays.

      While you can dim them that way, they are very picky and inefficient. PWM is much, much more efficient and allows for nearly 1-100% dimming range easily. Getting such accuracy with current is very hard, since it's nonlinear. Most LCD backlighting is done via PWM, there are tons of tiny chips to do this efficiently, for phones too. It's just too easy and cheap not to use PWM these days.

      --
      I don't know, but it works for me.
  7. We need lumens ratings by kherr · · Score: 4, Insightful

    The real issue is that all light bulbs really do need to have the rating of lumens. Wattage is power use, lumens is light output (obviously). Saying "40-watt equivalent" is empty marketing speak, no wonder they were disappointing. And then there's the whole light temperature issue, which is very difficult for a consumer to determine.

    For my LED experience, I went with these LED bulbs for my chandelier (I was looking for a "25-watt equivalent") and have been very pleased. It may help that it's a cluster of bulbs in my fixture. Considering the lifespan of LED bulbs, I'm willing to pay a lot more per bulb providing the light output falls in the appropriate range.

  8. Re:Wrong bulbs by Moofie · · Score: 3, Insightful

    I've heard this dozens of times, but never seen how to differentiate crappy CFLs from good ones at the store. It's not like they have labels like "Hey, this CFL sucks! You should probably buy something better!" and spending more money is no guarantee of quality.

    Do you have some reliable way to tell good CFLs from bad ones? I'd like to know how to do it.

    --
    Why yes, I AM a rocket scientist!