Fluorescent heating

Dec 24, 2008 37 Replies

Snip a few more paragraphs that you can read in the original post...

Easy on the eggnog Jamie ;-) Merry Christmas.

Tom

That was home made wine, and it was good! :)

"I\'d rather have a bottle in front of me than a frontal lobotomy" http://webpages.charter.net/jamie_5"

dissapate less heat, but still most of the energy consumed

radiate light - we just can't do it efficiently.

we are wasting so much energy. Flourescent lights

efficient at all, but much better then incadescent.

I'm not sure what the ratio is. Visible light itself is

Not yet.

Yes.

dissapate less heat, but still most of the energy consumed

radiate light - we just can't do it efficiently.

we are wasting so much energy. Flourescent lights

efficient at all, but much better then incadescent.

I'm not sure what the ratio is. Visible light itself is

Some white LEDs are pushing 160 lumen/watt now - at least if you believe Cree's press releases (they claimed 130 lumen/watt about 2 years ago).

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LEDs capable of 90+ lumens/watt are starting to appear in consumer LED lighting some of the claims made are a bit optimistic eg

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But there are very few fluorescents that can work as efficiently as that.

Consumer mass produced ones still lag a bit behind the best prototypes. Although for some coloured light sources like traffic lights and indicators LEDs can still come out ahead.

In answer to the original question a low pressure sodium lamp with the InO coating etched off the glass envelope would emit a pretty strong IR line source at very high efficiency (with a suitable low pass filter to stop the obvious visible yellow sodium D line escaping).

Regards, Martin Brown

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dissapate less heat, but still most of the energy consumed

radiate light - we just can't do it efficiently.

that we are wasting so much energy. Flourescent lights

efficient at all, but much better then incadescent.

I'm not sure what the ratio is. Visible light itself is

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High Lumen/watt is not all we need. The color temperature (Kelvin) and Color Rendering Index (CRI) are very important factors. Today I can't buy LEDs that have better efficiency than fluorescents with 2700K and >CRI90 for my home lighting.

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The other important factors are longevity (LEDs are typically 50,000+ hr), ability to work in cold environments, and the true environmental costs of manufacturing and disposal. I think there are white LEDs with a wide range of color temperature, and those that use RGB can be adjusted to whatever you need. Earlier white LEDs used a phosphor coating that made them less efficient, while newer ones I think use the light output directly, perhaps from a cluster of component colors.

Also the power conversion from line voltage to LED current can approach

97%, while I doubt that most CFLs are much better than 90%, but I'm just guessing by how hot the base of CFLs are. I think there has been a major investment in CFL technology and manufacturing that causes resistance to switching over to LEDs, and the fact that CFLs need more frequent replacement is also a plus for those who want a continuing business.

Paul

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This is my favorite

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This tube is 20 years old now and still going strong. I can't find any LED that have this light quality. 2700K CRI95

Those don't look like 500mW to me - the "most powerful" one is 35mW according to the datasheet.

John Devereux

This is the real answer.

Van Chocstraw >>\\\\--------------------//

It would be more efficient to heat ceramics with microwaves to get IR heating.

Van Chocstraw >>\\\\--------------------//

I was looking at radiant intensity at 1 amp, but the actual radiant power is only 35 mW at 100 mA and 350 mW at 1 amp. But the duty cycle drops to only 5%, so the maximum continuous power appears to be only 35 mW. Certainly not enough for any practical heating application.

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This one has 1.9 W/sr (210 mW actual radiant power), and 3.5 W input power, but I'm sure it costs a few dollars:

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Paul

I think laser diodes have the best efficiency; checkout the high power ones

$37k for 15kW optical output :)

Seems to be 40% "efficient", seems to be actual energy efficiency but I am not certain.

John Devereux

I thought that was God: "He sees you when your sleeping, he knows when you're awake; he knows if you've been bad or good so be good for goodness' sake!

Oh, you'd better watch out! You'd better not cry! You'd better not pout, I'm telling you why - Jesus Christ was born on this day!" >;->

Cheers! Rich^H^H^H^HBoBo

Every so often, I get inquiries about induction heating, from people who probably aren't well enough equipped (technically or mentally..) to tackle such an advanced project. So I always make it a point to find alternatives...

"What are you using it for?"

"Boiling water."

"..."

Tim

Deep Friar: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms

Do you ever post anything that's even remotely related to Basic Electronics?

Thanks, Rich

And not high at the same time?

http://improve-usenet.org/index.html aioe.org, Goggle Groups, and Web TV users must request to be white listed, or I will not see your messages. If you have broadband, your ISP may have a NNTP news server included in your account: http://www.usenettools.net/ISP.htm There are two kinds of people on this earth: The crazy, and the insane. The first sign of insanity is denying that you\'re crazy.

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