[Below is the original script. But a few changes may have been made during the recording of this audio podcast.]
It's the twinkling lights that make a Christmas Tree so festive.
And, the recent upgrades from the bulbous models of yesteryear, also shine a light on the future of lighting.
That's because many modern light strands are composed of LEDs—light emitting diodes. Diodes are electrical devices made up of two different materials that conduct electricity. In the case of the light-emitting variety, a semiconductor casts off light when electricity flows into it.
This is important as it is a more efficient way of producing light than conventional light bulbs, whose glow relies on heating tungsten filaments to at least 3,100 degrees Fahrenheit. LEDs are also more efficient than fluorescent light bulbs, which require less electricity than Edison's invention to excite gases to emit light.
Some LEDs under development require 10 times less electricity than an equivalent conventional light bulb and less than half the electricity required by a fluorescent light source. That has convinced cities from Raleigh, North Carolina to Anchorage, Alaska to adopt them for public lights.
The U.S. Department of Energy estimates that this switch would reduce electricity demand for lighting by 62 percent and avoid the need for at least 133 new power plants.
This would mean a lot fewer greenhouse gases going into the atmosphere and warming the earth, all thanks to a technology refined in part for your Christmas tree.