All of the LEDs you see in every device that you put your hands on is made with precious sapphire rock – artificially grown one, but still an expensive material to work with. A new technology developed by Bridgelux uses Gallium nitride to grow LEDs on silicon substrates and can be reproduced at commercial scales.
A prototype silicon substrate LED has already produced 135 lumens per watt of electricity, which is a notable breakthrough, 10 times more than incandescent bulbs and CFLs. So far, silicon substrate LEDs have not been able to emit enough light so they can be integrated in commercial applications.
Two or three years is the time frame that Bridgelux estimates their cheap silicon substrate LEDs will hit the market. Related products include commercial and office lighting, residential lighting and so on.
For now, saving power with LED lights is a little prohibitive, but worthy if you think in the long run. An LED lamp that emits the light of an equivalent 60W incandescent light costs around $40, which is pretty expensive for many. Remember that the majority of those who want to save want cheap technologies, and not some they’ll recoup in a year or more.