The technology works by using accelerated electrons to stimulate a phosphor coating on the inside of the glass bulb. In contrast, incandescent bulbs run a current through a filament inside the bulbs, and LEDs stimulate semiconductors to create light.
The first ESL prototype is expected to output 40 lumens per watt with a 6,000 hour lifetime.
So why is the ESL bulb any better than CFLs or LEDs?
Vu1 claims that their bulbs do not have the trace amounts of mercury that CFLs contain, and they do not require the manufacturing energy of LEDs. At $12, the ESL bulbs cost about the same as dimmable CFLs. We can expect to see these on the market fairly soon—Vu1 says the first screw-in models could be available as early as September 2008.
With all the news about the growing popularity of LED bulbs, this development could be just the thing to keep the public eye on energy-efficient alternative lighting.