Graphite Foam Makes High Efficiency LED Lights Last Longer

August 28th, 2010 by Tina Casey

Chalk up another reason to make the switch to high efficiency LED lighting: Scientists at the Oak Ridge National Laboratory have developed a graphite foam that extends the life of LED lights. The foam is used as a passive cooling element, which plays a critical role in the lifespan of LED components. The breakthrough could help lower the cost of LED’s and make them more attractive in the mass market.

[social_buttons]

A wholesale switch to high efficiency LED technology could be part of the solution to the conundrum posed by the coming wave of new electric vehicles, which is how to manage overall energy consumption (and carbon emissions) when millions of new electric car owners start charging up their vehicles.

LEDs and Temperature

LED stands for light emitting diode, which is a technology for producing light through a chemical reaction (in contrast, incandescent lights work by burning a filament). Though they use less electricity than conventional lights, one drawback is their sensitivity to temperature. According to Oak Ridge, each 10-degree decrease in the temperature of an LED can double its lifespan. For this reason, LEDs are designed with “heat sink” components usually made of copper or aluminum.

Advantages of Graphite Foam for Cooling LEDs

Graphite foam is a lightweight material with a distinctive graphite crystal structure (graphite is a form of carbon, by the way – same chemical elements but different structure). The structure “wicks” heat away from the source and conducts it away without the need for mechanical cooling. Compared to copper and aluminum components, graphite foam is lighter and easier to work with, admitting the possibility of designing cheaper but more effective cooling elements for LEDs.

LEDs and Green Jobs, Too

By lowering the cost of LED’s the Oak Ridge technology could help precipitate a more rapid transfer away from incandescent bulbs across consumer markets, in addition to large scale installations at businesses and public facilities. None other than the U.S. military is switching over to LEDs, which could result in a boost for the LED industry that could mean a boost for new green jobs in the U.S. For example, tiny Ellwood City, Pennsylvania is looking at an influx of 400 new green jobs at a company called Appalachian Lighting Systems, which recently won a contract for what is believed to be the largest LED retrofit of its kind, at the Pittsburgh International Airport.

Image (altered): Foam by James Cridland on flickr.com.

Keep up to date with all the hottest cleantech news by subscribing to our (free) cleantech newsletter, or keep an eye on sector-specific news by getting our (also free) solar energy newsletter, electric vehicle newsletter, or wind energy newsletter.

Tags: graphite foam, Oak Ridge National Laboratory

About the Author

Tina Casey Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. Views expressed are her own. Follow her on Twitter @TinaMCasey and Google+.

Frank Hanlan

I think that this is great news. I would love to see the prices come down faster.

In Canada we are supposed to switch to CFLs as of Jan. 1, 2011 but LEDs are safer – no mercury and less emfs (?) – and use less energy.