Advancement In Lighting Technology!

[Underwurlde]

^ That is because you are not in the trade & buy piecemeal from a shop. On ONE of my products, designed about 2 years ago, my company buys in 2.5 million LEDs per annum: (Surface mount) 'Super-Brite' LEDs cost me about 2.6p each and that is AFTER the supplier mark up of about 8%.

 

[steelhealr]

It is true that you can dim LEDs. I created an 8 light 4000mc Blue LED moonlight on my FW tank and it was a nice product. The only tough part is soldering the capacitors to the LEDs. Creating your own would be QUITE a project..at looking how many you'd have to put into a board and then protect it against SW.

SH

 

[Underwurlde]

Capacitors?? LEDs don't require capacitors...

They don't even 'need' resistors if fed with a constant current supply.

 

[steelhealr]

OOPs..resistors...SH

 

[Redstratplayer1]

My lfs has all its sps tanks lit with Solaris LEds and the corals look great.

 

[JJ1234567]

My LFS also has a LED panel over their 90 gallon hard coral sale tank. IT is a beautiful fixture. I love the color spectrum on it as well. The fixture they showed me retails around 2300$, which is about twice what I have priced halides at there store. Factor in the following: no heat, so less/no chiller required; bulbs have a life of around 10 years at 12 hrs/day, where as Halide bulbs are uber expensive and have to be replaced yearly; runs on 45% less energy than metal halides, yet has the same reading on the light meter. I know when i get my big tank up and going, I will be springing for LEDs.

 

[Underwurlde]

LEDs will produce heat, just not as much...

 

[JJ1234567]

all I know is that I would not want to stick my hand under a Halide fixture that was running. I could stick my hand under this fixture with no noticable heat.

 

[Underwurlde]

True but think of it like this. There is only one halide, all the light therein comes from a VERY hot filament, 2" from your mit. Yes, its gunna get hot. For LEDs, there is not just a single LED producing the same amount of light, there are many spread out, also their substrates are bonded dorectly to heat sinks making them far far easier to cool. There is still heat produced by LEDs, just spread out more making it easier to cool.

 

[robbhp]

i could be wrong but i was once told that and led running at the right volts shouldn't even get hot nor should it ever burn out. but i do understand that the volts will allway go up and down thus killing the LED but heat wise, they must only put out such a small amount of heat.

 

[Underwurlde]

I think you may be talking about 'normal' LEDs such as those found in moblie phone keypads & back lights - these LEDs will not get hot enough for you to really notice probably 1/3 watt TOTAL over the area the size of your palm, buried mm's inside the cover. OK, granted with what you've said, IF you put too much voltage across them they'll get too hot & bust (as will any LED). You'd have to be holding the LED to fell it burning too hot, but it will be in it's failure mode.

Now lets take these new LEDs and take for example the new application for Aquarium Lighting. Not just one LED could be used (well it could, but would get so damned hot it would de-solder itself or would have to be cooled using a radiation system - also the light intensity would be such that it would blind you) there are many, about 50 or so. These LEDs would weigh in at 1.5W to 2.0W a pop and perhaps use about 50 (I'm talking the $2000 types here).

Look at this little baby: http/dmcleish.com/Nichia2W/index.html
See the first picture on the penny? The little tab on the left is there such that the LED HAS to be soldered down to a large copper area so that the device can be heatsunk - i.e. connected to a PCB radiator. These things WILL get hot. however, OVERALL these lights won't get AS hot for an equivalent Halide. I think 75W of LED cluster equtes to producing 95% of the usable light that a 250W halide will, therefore only dissipating a third of the heat. As I said, consider also that this heat is spread over a greater area of 50 LEDs instead of one great big heat producing Halide.

For the cheaper systems smaller LEDs are used but again, more are need and you'll end up dissipating the same power but again even more spead out over say 200 LEDs...

Andy

 

[andywg]

In the topic I linked to above, I linked to a review undertaken on a Solaris LED fixture.

Here is the link

And here is a quote about heating:

PFO advertises that all heat generated by the LED array is directed away from the aquarium. To test this claim, the Solaris was placed atop an aquarium and about 2" from the water's surface. The Solaris was allowed to operate continuously for about 27 hours, and temperatures were measured by an infrared heat gun and a "laboratory" thermometer. In all cases the water temperature did not exceed room temperature (maintained at 24.3ºC by room air conditioning). The top of the luminaire is vented, and it did warm to 25.5ºC while the bottom (lamp side) stayed at room temperature. It appears that PFO's claims are accurate.

The review notes that while the 75W LEDs produce less PAR than a 250W MH, they produce more PUR (photosynthetically Usuable Radiation) so give out more light that can be absorbed by corals. SO more light, for 30% of the energy costs. Then you factor in the saving of around £20 per year on bulbs and they aren't so bad.

However, very few aquarists consifer the long term costs of equipment, otherwise we would all be using Tunze Streams for powerheads. The upfront cost will put people off, for now.