It's a new fluorescent bulb that could have a bright future — the cold cathode fluorescent lamp (or CCFL). These bulbs contain half the mercury of conventional "hot cathode" fluorescents. They have a thinner tube diameter, which allows them to run cooler, and last up to four times as long (a lifespan of 25,000 hours). This means that the mercury is reduced by 85% over the life of a cold cathode bulb, because a regular CFL would have to be replaced three times during that period. Another big advantage of CCFLs is that they are fully dimmable, and "on/off" cycles do not shorten their life. This means they can be used with motion detectors and standard incandescent dimmers.
I realized the potential of these bulbs, when Paul Gaiser of Better Bulb in Bethesda, Maryland, gave me demonstration. He showed me a cold cathode 13 watt bulb that replaces a 50 watt incandescent. The CCFL had a pleasing "warm white" light (a color temperature of 2700 degrees Kelvin). The retail price for this bulb is $15, which is actually quite reasonable, given the lifespan of the bulb. A 18 watt bulb is in the works, which will replace a 75 watt incandescent.
Paul also sells a couple of other interesting cold cathode bulbs, which I will cover in forthcoming posts.
Cold cathodes seem to have a lot of offer. They significantly reduce the mercury problem of the conventional CFLs and are more stable all-round. They last about as long as LEDs, yet the bulbs are much less expensive ($15) than an equivalent LED-based light ($70).
See also my previous post: New Cold Cathode Bulbs Can Be Dimmed, Switched
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