Most light-emitting diode (LED) used as indicators generate so little heat that they have lifetimes measured in decades, but high-intensity LEDs used for solid-state lighting will burn-out in just a few hours unless they use heat sinks to lower their temperature. Look for novel cooling methods for LEDs as solid-state lighting comes online over the next ten years. RColinJohnson @NextGenLog
ORNL researcher James Klett shows street light fixture retrofitted with an LED array cooled by ORNL's graphite foam material (bottom) that can extend their lifespan.
Here's what EETimes says about keeping high-intensity LEDs cool: Light-emitting-diodes (LEDs), once quoted to have 100,000-hour lifetimes, are still working today in some front-panel indicators after 30 years of service. But the advent of high-intensity LEDs for solid-state lighting sacrifices longevity by operating at temperatures too high for lifetimes much longer than a few years. Now Oak Ridge National Laboratory (ORNL) claims to have rolled back the calendar on LEDs with a graphite foam material that keeps even high-intensity LEDs as cool as those used for front-panel indicators, thereby reclaiming their long lifetimes. ORNL recently granted an exclusive license for their graphite foam technology to LED North America (Oak Ridge, Tenn.) an ORNL-spinoff located in the adjacent Technology 2020 "incubator" park...
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