Okay, I've been doing some research on LED grows and from what I found, It's really not worth it at all! It really wont be worth the buy for another 5 years. The out put of the LED diminishes after just a few inches! I've seen grow vids, read plenty of journals, and know someone that has been growing with LED's.
The best I've seen on a LED grow, is 30 grams, with 10 plants. They just aren't strong enough YET!
First, I'd like to know where you come up with your time scale. 5 years is a LONG time, technologically speaking. Siemens, the European engineering leader, is projecting that by 2012, the market for LEDs will triple (to over 13 billion euros). Did you know that the European Union has been phasing out clear incandescent lighting above 100W? By 2012 there will not be any incandescent light bulbs sold at all, in any of the countries comprising the EU. They also have stated that high-power halogens will no longer be allowed to be sold. How long do you think it will take before they do the same to HPS and MH bulbs, considering how awfully inefficient they are? Don't think that this is just the rest of the world. GE will be closing its last American factory producing household incandescent lighting in July 2010. But I digress -- I'm not here to argue time scales.
What I
am here to do, though, is point out that you clearly haven't done very thorough research. I, myself, have a link in this thread that will take you to a project that has been posted on multiple forums. It's a guy who did at least one verified grow with 2 - 300W LED lamps. I'm not going to post the link again, if you want it, you can go through the posts and find it. Anywho, he pulled 540g of dry weight off of 18 plants, not including fluffy buds. I think that's pretty respectable for 600W of light.
As far as the light output from LEDs go, you are simply wrong. Well, ok, you're wrong and you're right. What you're right about is that the light DOES diminish exponentially the farther away you get from the light. What you're wrong about is the implication that LEDs are the only light that suffers from this problem. Light is light, buddy -- it doesn't matter if it's sunlight, plasma lighting, LEDs, HID, incandescent, or just those little lights that you put on your tree at Christmas. All of them follow the Inverse-Square Law, meaning the intensity of all light depletes at the same rate based on distance. It all depends on its initial luminous intensity -- again, this is only a human interpretation of light, as luminous intensity has no real application to plants and photosynthetic production. Speaking of which, if you were simply saying that the output you
see diminishes after only a few inches, I agree -- because we, as humans, have not evolved to be able to sense the majority of the electromagnetic spectrum.
Until you can post some of your own results, or get your "friend who's growing with LEDs" on here to post some comparison pictures, or at the VERY least post links to other grow journals and vids, everything you say is anecdotal. Nothing in your post supports what you're saying. I will agree, however, about there being many others out there who have tried LED lighting and have gone back to HID. In every single one of those threads/posts/journals, the grower was trying to get too much out of too little light output. In addition, the lights were typically the eBay specials -- the ones that are cheaply made with the wrong wavelengths. People seem to think red is red is red, and blue is blue is blue. If I remember correctly, I even found a journal along the way where the grower was trying to use the brake light LED from his car to power the grow. When it didn't work, he swore off of LEDs for good. But he didn't even consider the fact that it wasn't the correct wavelength. He had simply heard that using red LEDs would increase his yield.
I am not trying to shoot you down, here, but you have to realize, as I have told several others in this thread -- This thread is for people who have QUESTIONS, not opinions. This is a discussion of the potential benefits of using a quality product, as well as the potential disadvantages. If you really feel that LEDs don't work, feel free to start a new topic. That's the beauty of a forum.