The incandescent light bulb is a quintessential American invention, discovered by Thomas Edison more than 125 years ago, but its future seems to be fading to black amid an ever-greening society. As Americans become more environmentally conscious, consumers are being pushed to buy more earth friendly products including compact fluorescent lights, or CFLs, the latest help-the-planet issue du jour among concerned citizens.

At the federal level, President Bush signed an energy bill in December that, among other changes, will require all light bulbs sold in the United States by 2014 to be at least 70 percent more efficient than today. For those of you that haven’t already connected the dots, the mandate means that, without major improvements, incandescent bulbs will disappear from store shelves by 2014.

After Congress delivered its comprehensive energy bill to the White House in a Toyota Prius hybrid car, U.S. Rep. Jane Harman, a California Democrat, waxed poetic about light bulbs, noting that little had changed since Edison and his glass tube and filament. “When it comes to illumination,” Harman said, “we still live in a cave.”