Lighting Revolution with New Generation LEDs

What the transistor did for electronics, LEDs are about to do for photonics say researchers from Rensselaer Polytechnic Institute of Rochester, New York.

If all of the world's light bulbs were replaced with energy-efficient LEDs for a period of 10 years, researchers say it would reduce global oil consumption by 962 million barrels. Not only that, but the financial savings would be $1.83 trillion, and carbon dioxide emissions would be reduced by 10.68 gigatons. That's a pretty impressive triad: energy efficiency, cost savings, and reduction of pollutants!

And it's not science fiction. LEDs (light emitting diodes) can generate light twenty times more efficiently than conventional bulbs. Not only that, but LEDs are "smart" light sources. Control of spectrum, color temperature, polarizaton, temporal modulation, and spatial emission patterns are possible with LEDs.

Photonics is the new discipline, merged from semiconductor technology and optics. These uses include illumination, communication, sensing, and imaging. Deployed on a large scale, LEDs have the potential to add new and unprecedented functionalities to photonic devices.

Since 1880 when Edison discovered how to convert electricity to light a key issue has been the "luminous efficacy." This simply means how much light you can get out of a watt of electricity, measured in lumens per watt. The modern incandescent bulb produces about 15 lm/W, and a compact fluorescent bulb- the kind we are all putting in our homes now is 65 lm/W. The new LEDs are about 180 lm/W with a theoretical limit over 300.

Continuing the comparison to the transistor, the transistor was first seen as a replacement for the vaccum tube. Ultimately its use went far beyond that replacement paradigm. The same type of scenario is likely with LEDs. They will be much more than a replacement for the light bulb.

Some potential uses of "smart lighting" include rapid biological cell identification, interactive roadways, boosting plant growth, and better supporting human circadian rhythms to reduce an individual's dependency on sleep-inducing drugs or reduce the risk of certain types of cancer.

To continue the research a Smart Lighting Center has been funded at the level of $18.5 million over five years from the National Science Foundation.

"Sustainability and energy efficiency are two key challenges of our time, yet they also present rich opportunities," said Rensselaer President Shirley Ann Jackson. "With innovation, ingenuity, and a clear vision, the NSF-funded Smart Lighting Center at Rensselaer will rewrite the rules for manipulating light and help introduce these new green technologies to the world."

Along with broadening the knowledge base of smart lighting, the center is expected to be a hub for commercializing related technology, where students and academic researchers work side-by-side with companies large and small to test, validate, and bring new products to the marketplace.

See the full news release from Rensselaer Polytechnic Institute