SLOW AND STEADY
"Studies suggest that a complete conversion to the lights could decrease carbon dioxide emissions from electric power use for lighting by up to 50 percent in just over 20 years; in the United States, lighting accounts for about 6 percent of all energy use. A recent report by McKinsey & Company cited conversion to LED lighting as potentially the most cost effective of a number of simple approaches to tackling global warming using existing technology..."
"LEDs are more than twice as efficient as compact fluorescent bulbs, currently the standard for greener lighting. Unlike compact fluorescents, LEDs turn on quickly and are compatible with dimmer switches. And while fluorescent bulbs contain mercury, which requires special disposal, LED bulbs contain no toxic elements, and last so long that disposal is not much of an issue."
And then some of the challenges:
"Though the United States Department of Energy calls LED “a pivotal emerging technology,” there remain significant barriers. Homeowners may balk at the high initial cost, which lighting experts say currently will take 5 to 10 years to recoup in electricity savings. An outdoor LED spotlight today costs $100, as opposed to $7 for a regular bulb.
Another issue is that current LEDs generally provide only “directional light” rather than a 360-degree glow, meaning they are better suited to downward facing streetlights and ceiling lights than to many lamp-type settings.
The technology driving this innovation is changing rapidly, so that we may see some of these metrics change markedly for the better in the near-term. In the meantime, LED lighting does seem to be the low-hanging fruit in going green.