2011-06-06

LEDs: A Chicken & Egg(ish) Problem, For Now

Yesterday, I read a Yahoo! Finance news article (Gwendolyn Bounds, Wall Street Journal) about the current alternatives to incandescent light bulbs, given that the US will phase out sales of incandescent light bulbs by 2014. I also read some of the comments, many of which griped about the high costs of alternative lighting solutions and complained about government intrusion into their choice of light bulbs.

The story caught by interest because my work at NIST now deals directly with LEDs, and while LEDs have their benefits, they have their problems too. Some of the benefits include huge efficiency gains over comparable incandescent and even compact fluorescent light bulbs, as well as a much wider variety of applications. In addition, unlike compact fluorescent lights, LEDs have no mercury, so there is no toxicity risk associated with LEDs. However, there continue to be issues. One is that because LEDs (and this is true of fluorescent lights as well) do not produce light through heat like a blackbody (as incandescent lights do), the "warmth" of the LED's color can come close to but will never match that of the incandescent light, and this bothers many consumers; related to this, both LEDs and fluorescent lights exhibit flicker, which can be noticeable and irritating at some voltage frequencies. Another is of course that while compact fluorescent lights are now competitive price-wise with incandescent lights, LEDs are still relatively quite expensive (4-5 times more expensive than a comparable alternative); hopefully prices will continue to drop, and hopefully that happens soon. Adding on to that previous point, the efficiency gain of LEDs over comparable compact fluorescent lights is quite a bit less than the gain of the latter over incandescent lights, meaning the overall higher efficiency doesn't quite justify the higher price. Finally, there aren't yet good standards governing how to measure various technical specifications of LEDs.

This is why I'm excited to be working at NIST. At NIST, I'll be helping in at least a small way to test various LED components and make better LED standards. I'm also looking with other people into ways to eliminate flicker and improve both efficiency and color quality. Finally, I hope that all these efforts also result in cost reductions over time.