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LED Lighting As Cheap As CFLs Invented
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.'"
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.
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.
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.
If you only replace them at 1/10th or 1/1000th the rate then its unlikely it could be bad for the environment....
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.
"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.
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.
So what is the energy consumed during production for one of these LED lights?
If we're just using more energy per unit during manufacture, then what is the energy payoff balanced vs. the number of hours these will remain in service?
Just by quick examination, it's an enormous energy payoff - think about how incandescent bulbs are produced, or even CFLs, then imagine a boatload of Si/Ga wafers being produced (uses a bit of energy), and then 150,000 LEDs coming from each wafer. Then each low-wattage LED running for about 70,000 hours.... each LED bulb that replaces 70 incandescent bulbs, or 7 CFLs (approximately). LEDs use far less energy than either of those. It's not like manufacturers love using tons of energy to produce a silicon wafer.... they make the process as quick and efficient as possible - the cost of production ($15) is directly proportional to how much energy is consumed in the process.
Let's do a quick estimate, shall we? $15 per wafer, with a wafer yielding 150000 LEDs, 25 of which are needed for an array for a bulb = $0.0025 per bulb (just leds). I'd say the energy savings will be on the plus side after manufacturing.
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!
But I have yet to find truly warm non-tungsten/halogen/mercury/fire/quartz/evil light for home use.
I thought the same for the first week after we started migrating our home to CFLs. I've since come to understand that "warm" is a synonym for "ugly yellow".
Dewey, what part of this looks like authorities should be involved?
I use CFLs, though I've had 3 out of the 8 I installed go bad within the first 2 years of use and still haven't found the time to "properly" dispose of them.
I too use CFLs. Like you I have 3 that burned out, however one lasted about 20 years. I don't know how long the others lasted. Also like you, I haven't disposed of them either. I put them in a room nobody uses in the packaging some of the CFLs I bought came in. When I find out where I'll take them in for recycling. I heard Home Depot was starting to accept them for recycling but I haven't seen my local store with a place to put them.
Falcon
Should there be a Law?
I get my power from HYDRO!!!!
Are you hooked up to the grid or do you have a micro hydro system?
Tell that to the environmentalists who won't let us build dams, water wheels, nuclear power plants, or anything that actually makes sense.
Dams are not environmentally clean, neither are nuclear power plants.
Falcon
Should there be a Law?
I see it a different way.
If gallium becomes scarce and expensive, then aluminum prices will drop. This will bring us cheaper, stronger, lighter, and less bio-degradable cars.
I, for one, welcome our gallium-based LED lighting overlords.
Kid-proof tablet..
"While not considered toxic, the data about gallium are inconclusive. Some sources suggest that it may cause dermatitis from prolonged exposure; other tests have not caused a positive reaction."
-wikipedia
You must be thinking of a different metal.