really funny! obviously they don't know cfls can't be made without mercury!

http://lowermacungie.patch.com/articles/cfls-are-good-and-bad-seven-gen-student-says

Quote: "The mercury inside a CFL makes it last longer and saves energy. An incandescent light bulb has no mercury so it doesn’t save energy and doesn’t last long."

(...). What is the relationship between mercury and longer life and energy saving. Life of a CFL, isn't longer because of the mercury, the life is determined by: Ballast component quality, amount of mercury dosing, starting method, electrodes design and emssive coating dosing. Efficiency of CFL over incandescent, isn't higher because of the merucry, but because less IR is emitted, but in fact, CFL is the secibd least efficient discharge lamp available, after the SBMV lamps.

CFLs without mercury: There are actually several CCFL lamps that operates without mercury. Usually these are scanning lamps for digital copiers and some PC scanners. Osram Planon flat fluorescent lamp was also mercury free.
All of these lamps, uses Xe2 (Xenon excimer). However, these lamps are less efficient than regular mercury based fluorescent lamps, and have only around 50lm/w max. If this technology will be improved, so higher efficiencies could be achieved, this will be good, since the lamps will have no run-up time, no problem of gas starvation (As occurs with mercury), less degradation of the phosphors (Which partially caused by chemical reaction with the mercury), and not only by heat and loading. and better lumen maintenance (Since it will be exclusively based on the phosphor degradation, which will be reduced).

Xenon discharge based lamps can not be made more efficient, because the Xe by itself already emits a lot of energy in the IR.

And even when there would exist any other possible discharge base, it won't be introduced. The reason is the amount of money such concept would ask as investments into the technology.
Nobody would invest huge amount of money into something, what would remove only some milligrams of mercury, but still keep all the drawbacks related to discharges: Hot electrodes, UV generation, efficiency drop with lower power packages (electrode losses), fragile, difficult/impossible to mass produce and at the same time keep the flexibility for final product design,...

Mainly when today the LED's become "cash cow" for their makers...

Read only the beginning. Let me modify it a bit :

I am a deer and im laying on the earth and bleeding to death, because i eated this white object and it shattered and the glass cut me to pieces

What i see the kid saying is basically "littering is ok, so please give us green stuff that we can freely litter the planet with without feeling guilty"

Read only the beginning. Let me modify it a bit :

I am a deer and im laying on the earth and bleeding to death, because i eated this white object and it shattered and the glass cut me to pieces

What i see the kid saying is basically "littering is ok, so please give us green stuff that we can freely litter the planet with without feeling guilty"

Well said, Ash...

yep gas discharge technology is dead in the water, i believe they may disappear in about 10 years. in fact the only reason they were used is because of the higher efficiency and longer life than incandescents, while incs maintained a stronghold in homes and restaurants because of their better color quality. discharge technologies are also expensive to make compared to leds, especially high intensity discharge lamps. for example some led track lighting systems are already cheaper than cermaic metal halide systems (but the latter still currently have an advantage in offering higher brightness packages). we will be like the vacuum tube collectors and classic car restorers holding onto the old stuff while the rest switch over to new tech.

I think it is like obsolete newspaper which we still read that would not die despite the internet news that we read today.

Ditto with qwerty keyboard that is been holdover from the late 19th century to reduce keystroke jamming

In my own opinion, the old technology will not go away as long as the consumer continues to demand these replaceable parts.

In my own opinion, the old technology will not go away as long as the consumer continues to demand these replaceable parts.

But only if they would be willing to pay the higher cost.
And as the use would drop, the cost to manufacture single piece would rise, yielding further drop in demand and so on, so there would be no maker willing to keep that technology running...

Unless it can be improved to have some other advantage over LED. How about lifetime, reliability, CRI and so on

Unless it can be improved to have some other advantage over LED. How about lifetime, reliability, CRI and so on

Technically it would be hard to (ultimately) outperform the LED's:

On the efficacy because the LED's use direct conversion to the visible light. Even when the practical source need some phosphor conversion, the ultimate efficiency could be ~70% (assume no losses except of the photon energy loss, when converted to longer wavelength).

On the lifetime the LED depend only on the operating conditions. When their price drop, they could be operated at lower current densities and lower temperatures, so the life could be practically unlimited (>100years), while still maintaining the high efficacy (such conditions would actually make their efficacy higher)

CRI is matter of design trade-off towards the efficacy. And this trade-off is principal for all light sources, unless they already radiate majority of their power outside the visible range (incandescent). If you allow lower CRI, you may concentrate all of your radiated power into the area, where the eye is most sensitive, in order to get maximum lumens. But if you want high CRI, you have to radiate significant power as well on wavelengths, where it practically does not contribute to the "lumen" output, so your efficacy would be lower.
With tungsten incandescent you have no choice, it radiate in way wider area. But if you would have a means to control it (e.g. by making the surface "black" only for wavelengths you want to radiate and "white/mirror" for all others), you end up with the same trade-off problem: If you choose to not radiate in deep red and blue, you get low CRI...
And as with all quantum based light sources you have at least some choice, where to radiate and where not (gas fill composition, phosphors,...), you could adopt this trade off according the application needs.

Wait, wait, wait wait wait.... I'm confused.  

First the kid says:
"...light bulb makers should make a CFL without mercury because it still could save energy..."

Then later says:
"The mercury inside a CFL makes it ... save energy."

I see some flawed logic here...  

Also:
"I think we should use solar power light bulbs because they take energy from the sun to power it."

Solar powered light bulbs, eh? That's kind of redundant.  

All kidding aside, it's nice to see a kid that young who's attempting to understand part of what's undoubtly an ecological problem. I wasn't worried about that stuff in fourth grade. Then again, back then people didn't fear fluorescent lamps, and CFLs were decent enough that it was rare to find one in the trash.

Solar lightbulbs do exist actually and are usefull in multi storey buildings. They are made of a collector on the roof (mirror/dish setup), optic fibers going from there to the inner rooms of the building, and diffused light emitters (those are sometimes combined with fluorescents in the same troffer)

The term "solar powered lightbulb" could also mean the solar cell charged battery and then light after dark...
But most likely it is just a combination of "popular" "green" words...

Yeah, I figured he (maybe) meant as in a solar-powered battery backup system, but it's fun to play with words.

but it's fun to play with words.

But not anymore, when a result is such article. You know, in the time of the mandatory military service here (about 10years ago and earlier) we used to name-call the professional soldiers as "Green brains".
Well, these eco-activists, usually publishing such articles, "earned" to be called "Green brain-less"...