once upon a time, not long ago, when people wore pajamas and lived life slow-
i thought about using led's.
dismayed by the high cost of horticultural grade light panels, i decided to do some research on the matter.
since i am a lazy fucker, and my eyes aernt quite what they used to be, i decided to read someone elses research instead. i mean why waste countless hours of sifting through books and articles at the library when someone else has already done it, and more extensively than you or I could ever imagine...
So I contacted the good people at NASA. its nice to see our tax dollars at work at something useful for a change.
this was 5 years ago...
here's the skinny-
red and blue led's will provide adequete lighting for leafy plants, such as lettuce, parsely, cabbage, etc etc.
however it sucks for anything else, especially anything that bears
fruit or heavy flowers
green led's are completely useless. useless! turns out the only thing green light does is give the plants there color, im not exactly sure why this is, but they say it has to do with reflected wavelengths. leafy plants grown under red/blue light combos with a
total absence of white and green light grow fine, except there leaves take on a dark, blackish hue. there is no discernable taste or nutritional difference, just color.
however they (NASA) discovered something else quite remarkable about led's in the process.. in humans- the entire article can be found here:
http://www.nasa.gov/centers/marshall/news/news/releases/2003/03-199.html
but back to plants and led's... currently, the shuttles use a high tech version of t5's. however, they are inefficient for 2 reasons, 1- takes too much power... what? yep. floros are inefficient at converting power into light, and the light you get is simply not suitable for agriculture. it might grow some pretty spices and little flowers, but if you want plants that produce... well the t5's just dont cut it. they are ideal for vegging, but like the red/blue led's they dont have a high enough intensity for what we want them to do. 2- heat generated by ballasts is apparently a pain in the ass to deal with in space... not a problem for us but it was a problem for nasa. so for the international space station, and future trips to the moon and mars, a more efficient means of generating light for horticulture was deemed a requirement, so the boys in the back went to work, and heres what they came up with.
they were unable to develop an
efficient LED panel for plants that produce fruit and heavy flowers. After many tries, it was decided that LED's would be used in a small, self contained hydroponic grow chamber, that was to be used as (drumroll) an herb production chamber. spices like oregano and parsley, and a strain of lettuce developed especially for the space program. the chamber is supposedly in the experimental phase now, and may have been used on the recent shuttle mission that just landed.
for the future, and to solve the problem of efficient lighting for space based agriculture, it seems that the people at U of A in huntsville in conjuction with the marshal space flight center are now developing sulphur-microwave lamps to be used for plants that bear fruit, and tubers like potatos and turnips. they say its the most efficient form of lighting ever devised by man, and has been in use commercially since 1993, used specifically in aircraft hangers and olympic sized gymnasiums. unlike the original microwave lamps that came out circa 1990, and were immediatly banned by the FCC due to electromagnetic interference with wi-fi frequencies, these new lamps do not have magnetrons, and instead utilize a 'light bar' to distribute light evenly along the length of the light bar. it works similar to fiber optics, in that the lamp is placed at the end of the tube, light travels through the tube and somehow (dont ask me how, im not a physicist) is dispersed evenly throughoout the tube and directed downward. One example of this technology is the National Air and Space Museum, where 3 (just 3) sulphur microwave lamps replaced
96 1000w MH HID lamps... LG is also rumoured to be in on the project, and may have a lamp/fixture available for mass production sometime by the end of summer 2011.
so thats what i found out about lighting using LED's, from people that know more than all of us put together and have a budget, brains and the manpower to do all the things you always wanted to try. NASA, with its billions of dollars and thousands of cream of the crop scientists and dozens of universities at its disposal has decided that LED's are unsuitable for the type of growth we want, so im inclined to listen! though its fun to see the breakthroughs you guys achieve with LED's your doing work that was done almost 6 years ago, with products that are only now begining to become available to you, as the general public; and to me, its like your driving down a road that someone else has already been down with a better 4wd than yours, and got stuck... but you keep on driving anyways... but anyways, thats my .02 or .10 however you want to take it, im not knocking LED's, just IMHO i dont see how they are viable when it appears that you can achieve similar if not better results using CFL's or small HID lamps, at less than half the cost, and before someone says 'but led's are low wattage devices, and they will pay for themselves in savings vs HID'... how long will it take to pay off a 700$ led fixture by saving 5-10$ a month on power.....
that being said, i wish you guys and gals the best of luck!
BKB
) and since then had read a lot of negative things. However after reading the info on lights here, I am thinking twice. 
even i dont know what its going to look like and the start date is sheduled for march 2011. im back in development mode reserching and calculating etc etc. its gna be a whole heap of fun 
