UV LEDs: A Cool Alternative to Arc Lamps

Affordable reliable UV LEDs applied to HVAC units might go a long way to reduce airborne diseases which in turn should offset the costs by reducing lost productivity and health care load.

Definitely. HVAC units currently use bulb technology, which is expensive and tends to degrade over time. LEDs would last much longer and would be much cheaper to operate.

http://www.americanultraviolet.com/hvac-air-cleaner.cfml (here's an example of bulb based HVAC units)

Notice the chart on their page detailing how UV bulbs degrade over time.

Roger, this is interesting,

I have design UV systems for brining operations use in tantum to ultrafiltration units to control bacteria.

And to get the most effective results, I went with pulse UV from Xenon Corp. With the high energy usage (waste) and maintenance, I'm somewhat disappointed, I'll have to look into this solid state applications and if it is comparable.

Thanks,

No problem. Here's some info that might help:

Here's some info to help.

http://optics.org/news/3/4/26

I've been using UV LEDs for several years now to generate fast (10s of nanoseconds), high-rep-rate (~100 kHz) UV pulses. Try doing that with an HID lamp! A lot cheaper than using xenon strobes.

Welcome back. I miss your posts which now seem to be few and far between.

As an electrical inspector in a region where all of our electrical energy is generated by fossil fuels (read diesel) imported once a year in tankers, the promise of this technology is well understood and is anticipated with baited breath.

For those connected to a large national grid, the promise of this technology may not be so apparent. For us not so connected... this could offer us limitless advantages. I look forward to seeing the report. When will it be published?

Getting pretty tired of paying 60+ cents per KWh. Only advantage... large fault currents are not something we have to take into consideration much in our designs. LOL... we stall generators before we melt switchgear.

Try doing that with an HID lamp! A lot cheaper than using xenon strobes.

That's what happens when you get in a rut of that's the way I always did it. Its unfortunate, but a lot of my tech journals I get now ^{(I had to drop a few, over load of info)} have drifted away from this topic.

Tech journals are certainly not as 'meaty' nowadays. Years ago there were articles that made some journals almost worthy of 'desk reference' status. Not so today. Rarely do I see an article that contains truly useful info. Worse are the so-called 'science' journals.

Some months back Scientific American posted an article that the editors lifted straight off Nature's pages and pasted to their own website without even bothering to proofread the result. What their copy-and-paste failed to do was carry over the formatting, with the result that all the equations in the piece were rendered gibberish. Either the editors didn't notice or, worse (far worse), they couldn't tell it was gibberish.

I've been fascinated with LEDs ever since seeing my first one in 1973. Amazing how much better they are today. That green LED (which cost $5 in 1973 dollars; about $26.60 today) was no brighter than - and about the same colour as - a firefly. Bought my first blue LED in 1984 for $60. Powder blue; it was so broadband that the breadth of the band included most of the visible spectrum. Silicon-carbide job from Siemens.

LEDs have certainly come a long way. A looong way.

I used xenon because their site had what I felt at the time was a wealth of information, even if it was molded are there products.

Xenon has the advantage of being intense as well as offering considerable choice in intensity. UV LEDs have only recently begun to offer same in both intensity and wavelength. Gas-discharge lamps still reign supreme in the really short wavelengths (< 200 nm).

Speaking of which, one problem with UV LEDs early on was their brief lifetimes; a few thousands of hours or less. Those short wavelengths tend to degrade the active LED material over time. For my part I'd like to see more about UV LED lifetimes. This aspect is not often mentioned in the literature.

I agree, I mentioned earlier on the maintenance aspect. The UV LED's sounds pretty promising.