Sunday, April 16, 2006

Better LEDs, Better Investment

Scientific American reports on a new generation of white LEDs.  Developed at the University of Michigan and the University of Southern California, they produce 25 lumens per watt.  That is 67% better than the 15 lumens per watt we get from incandescent bulbs.  
Electrical engineer Stephen Forrest of the University of Michigan, chemist Mark Thompson of the University of Southern California and their colleagues created the so-called organic LED by combining two layers of phosphorescent diodes--to release green and red wavelength light--and one layer of a fluorescent diode to supply blue wavelength light.
This is a bit of a curiosity: the device uses both fluorescence and phosphorescence.  The article implies that the only remaining technological obstacle is that they have to figure out what kind of coating to put on it, to keep moisture out.  That is not expected to be a big obstacle.  Lighting accounts for 22% of the electricity used in buildings.  These devices would reduce that by 60%.  Savings actually would be greater, in those buildings that are cooled by air conditioning.  

Reducing energy consumption is the best thing we can do to make our country safer.  It almost does not matter what it costs.  We're spending about $150 million on day on the Iraq war.  Getting better lights would be a better investment.