LED lighting was once relegated to basketball scoreboards, cell phones, traffic lights and colored Christmas lights. But as a result of rapid developments in the technology, it is now poised to become common on streets and in buildings, as well as in homes and offices. Some American cities, including Ann Arbor, Mich., and Raleigh, N.C., are using the lights to illuminate streets and parking garages, and dozens more are exploring the technology. And the lighting now adorns the conference rooms and bars of some hotels, a corridor in the Pentagon and a new green building at Stanford.

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.

The switch to LEDs is proceeding far more rapidly than experts had predicted just two years ago. President Obama’s stimulus package, which offers money for “green” infrastructure investment, will accelerate that pace, experts say. San Jose, Calif., plans to use $2 million in energy-efficiency grants to install 1,500 LED streetlights.
Thanks in part to the injection of federal cash, sales of the lights in new “solid state” fixtures — a $297 million industry in 2007 — are likely to become a near-billion-dollar industry by 2013.