Can Christmas LEDs Save the Earth?

LED Christmas lights are made from different semiconductor materials layered together like an Oreo cookie. They cost twice as much, but last thousands of hours longer.

This year's hottest green Christmas products are LED holiday lights. LEDs, or light-emitting diodes, use the same technology as appliance indicator lights and fiber optic communication systems.

LED lights are made from two or more different semiconductor materials layered together like an Oreo cookie. Or, to be more precise, a cookie with one vanilla side and one chocolate side, joined together by white frosting. The chocolate side contains negatively charged electrons, while the vanilla side contains positively charged "holes."

When you plug the "cookie" into an electrical source, the negative and positive charges become attracted and flow toward each other. As each pair of charges meets in the middle, they combine to create a photon, a particle of light, which pops out sideways from the frosting. The photons come in different colors (wavelengths), depending on the type of semiconductor used. Or, the plastic cap covering the LED can be tinted to create different colors.

According to Philips, and other manufacturers, these "solid state" lights can last for up to 80,000 hours. There's no filament to burn out and no glass bulb to break. Plus, LEDs use only about 5 percent of the energy required to power other Christmas lights. For those of us who worry about reducing our electric bills, as well as our demand for power, this could be good news.

LED Christmas lights cost about twice as much as mini-light strands. Depending on how many hours you plan to run them, you might see a return on your investment within the first year.

For most of us, however, buying all new LED lights to replace perfectly good mini-lights, would be too expensive. I plan to use them to replace broken or burned out strands, as needed. Besides, in a few years, the price will probably come down as the technology matures.