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A Super-Efficient Light Bulb
Chroniton writes with news of a Silicon Valley company, Luxim, that has developed a tiny, full-spectrum light bulb, based on a plasma of argon gas, that gives off as much light as a streetlight while using less power. The Tic Tac-sized bulb operates at temperatures up to 6000K and produces 140 lumens/watt, almost ten times as efficient as standard incandescent lamps, and twice the efficiency of high-end LEDs. The new bulbs also have a lifetime of 20,000 hours. There's no mention of mercury or other heavy metals, which pose a problem for compact fluorescents.
I found it interesting that the tiny bulb - at least in the video - was still using 250 watts and internally generated a temperature of 6000K (no they weren't talking color temp; they were talking actual temp). Now that's certainly lower than the 400 watt conventional streetlight they compared it to; but there's no mention in the video about scalability or low-power use. So the submitter's comment about it having advantages over compact fluorescents may have no basis in fact.
#DeleteChrome
Heat and temperature are not the same thing. If it produces 140 lumens per watt, I believe that makes it something like 50% efficient (which is insanely high for lighting). That means a 100 watt lightbulb of this technology would turn 50 watts or so into heat, and 50 watts or so into light. A 100 watt incandescant is turning 85 watts into heat and 15 watts into light. So even if it runs at a higher temperature, its confined to a very small space.
This isn't dangerous at all.
I agree. The reason it hasn't killed professional ground based astronomy is that it is quite easy to subtract the very focused wavelength of sodium vapor streetlights from an image, as sodium vapor lamps are almost completely monochromatic. If we switched to these full spectrum lamps that would be much more difficult, probably meaning we would only be able to do astronomy in very remote areas or with orbiting observatories. That said, even as strong a proponent of astronomy as I am, the increased efficiency of these lights would probably make it worthwhile...
WTFV (watch the .. video). The temperature they're talking about really is 6000K in heat.
As other shave pointed out, this is not too much of a problem for household use as ordinary incandescents reach 3600 at the filament. You just need to encase it in a glass bulb.
it also affects drivers, and pilots as well. In some regions airports have pushed for local laws to limit light pollution going up into the sky as it interferes with planes landing. Spot lights can temporary blind drivers causing accidents.
Light pollution isn't so much about astronomy but being able to see when it is dark out, because some idiot is lighting up his yard like fen way park. At night less is more. I can use 5 watt 12 volt bulbs and light up your house better than spotlights. more of the house will be lit with less random dark spaces, and more importantly less shadows in which people can hid.
i thought once I was found, but it was only a dream.
Lights are not on all of the time. if less than 12 hours use which is likely than your calculations put the life at 5 years in a street light configuration.
In light physics, temperature and color temperature are the same thing. Color temperature refers to the temperature at which an ideal black body radiator will emit such a spectrum. This unit is obviously a temperature.
Moreover, this lamp appears to be a high bandwidth lamp -- "full spectrum" as they said. This implies that it does not depend on the absorbsion and emission characteristics of specific atoms. Lamps like these -- fluorescents, high efficiency sodium lamps, and the like -- emit light at discrete wavelengths. High bandwidth lamps depend on incandescence to produce light. Indeed, color temperature doesn't make sense for these kinds of lamps -- no black body radiator will emit discrete spectra. (There's a "corrected" color temperature unit for these lamps used in the lighting trade)
The point is: these lamps get hot. They reach about 6000K.
After all, I am strangely colored.
The real benefit is for radio astronomy. The far side always faces away from earth, which is a giant radio noise source, and the bulk of the moon itself blocks all the signal. It's really the only place where you won't get such interference (a few space probes notwithstanding).
The meek may inherit the earth, but the strong shall take the stars.
If you had ever spent much time in the countryside, you would know how well you can see by moonlight. I've been out during a full moon on a clear night and been able to play soccer with my friends. Driving requires that we can see dozens to hundreds of yards ahead, so need brighter illumination. We can see just fine outside at night for walking speeds. During the vast majority of our evolution we didn't have artificial light, but we did just fine, we still can.
We are all just people.
The benefits:
The Drawbacks:
They definately have some good applications, like for use in stadiums, airports, etc. However, I think there needs to be more research done to make them usable in homes and automobiles.
For any blackbody emitter (incandescent light bulb or this fancy new plasma), the color temperature IS the temperature. It's only for things that don't emit like blackbody radiators (fluorescent and LED) where you have a different color temperature than temperature.