Read those two articles. The 'Nature' original, full of concise factual information on the science, the technology, the future feasibility and shortcomings. Then I read the putrid BBC report, dumbed-down for a dullard mass-media audience and an insult to the intelligence.
Hee!, they are great for traffic lights and railway signals but they still miss the yellowish glow which we like in our houses. The colour rendering is not too good because LED's have a monochromatic light output. Incandescent lamps provide in winter some extra heating too An other thing is costs. A 240 volts LED lamp will probably cost at least NZ$100, ( US$60 ) as direct replacement for a normal bulb. See what happens?? Give it at least another 10 years I think.
The product of rotation, excitation and flux produces electricty.
My $0.02 worth. Considering that an incandescent lamp loses 94% of it's output as heat, it should be only a short period of time before it's demise, colour-rendering or not. LED technology is advancing in leaps and bounds and has been in the last 5-10 years as opposed to the development of the filament lamp since it was invented, in the 20th Century. Most of what is driving industry these days is finding a better, low power alternative to the light bulb. With singular LED outputs in the thousands of milli-candelas and with such a low current, it will be a short amount of time before the incandescent source is made obsolete. Couple that with the 300,000 hour life on an LED fitting. Take your pick.
The LED replacements would have to become as cheap as CFL's before they become prominent forms of domestic lighting. For other applications the incandescent lamp is pretty much obsolete...everything to do with signalling or indication is now using LEDs or about to. Portable lighting is rapidly changing now. LED torches have been around for a few years but today I saw a 12v lead lamp shaped like the familiar flourescent ones but internally was a panel of white LED's. The LED headlights on cars are the most vile thing I have seen and would ban them if I could. It is extremely unpleasant to have that 'spectrally pure' light shining in my eyes from an oncoming car. My stash of several thousand incandescent bulbs should see me out while the rest of the world has converted to CFL's & LED's. There really needs to be a 'warm white' LED for it to be acceptable. But then again, some people have no concept of colour temperature...the use of cool white CFL's in a living room proves that.
I didn't come floating down the Thames on a chocolate biscuit wrapped in bacofoil and I'm not paying $50 for a 60W lightbulb either, even if it does last 34 years. By then I'll be in my mid nineties and past caring. LEDs? Another catchpenny for people with more money than sense.
Sorry, That figure of 300,000 hours is incorrect. Lets try 100,000 hrs. Regardless, that is 100 times what you can expect from an incandescent lamp. AS240,
But then again, some people have no concept of colour temperature...the use of cool white CFL's in a living room proves that.
Here's a funny story, I use an old twin 2x 9W PL-S fitting here in my office to give light in here at night instead of using the normal room lights. Anyway, the current 4000K lamps were starting to get rather blackened and I thought it was time to replace them. Go down to my local supply house and get what I thought was the correct lamps and bought them home and proceeded to tear the boxes open and fit the lamps. Switch the fitting on, Good God!, they are the wrong colour (2700K!) and it looks like I have an HPS street-light on in here. The nieghbours must be thinking I'm growing some drugs in here. I won't get caught like that again.