LED to light crops in space

Ott/09 8 7

LED to light crops in space

Lampade di crescita a LED per il supporto vitale nello spazio To understand the dynamics of operation of the LED lamps in the growth of plants you can find useful information in studies on advanced life support by NASA for astronauts.

The draft long space voyages, such as to bring the man to Mars, is faced with the need to ensure food and fresh air to the crew during their stay in space.

The traditional lamps are not a viable option for growth, given the high power consumption and heat output. For this reason the search for alternatives is increasingly oriented toward systems that use LED panels, which show considerable advantages such as energy efficiency, emission spectra, stable, safer, low-heat, longer life, smaller size.

I found some very interesting material in the archives of the "American Society for Gravitational and Space Biology" and in particular in these 2 publications from which I have most of the information in this article:

"DEVELOPMENT AND TESTING OF AN EFFICIENT LED LIGHTING DESIGN FOR INTRACANOPY Minimizing EQUIVALENT SYSTEM MASS IN AN ADVANCED LIFE SUPPORT SYSTEM." in 2005 (D Mass Joy, Jeffrey C Emmerich, Mick ME, RJ Kennedy, Robert C Morrow, Gary A Mitchell)
"PLANT-GROWTH LIGHTING FOR SPACE LIFE SUPPORT: A REVIEW" in 2006 (D Mass Joy, Jeffrey C Emmerich, Robert C Morrow, C Mike Bourget, Cary A Mitchell)

The "Advanced Life Support" (ASL) NASA is also developing crops for food production, in support of human life in extraterrestrial environment.
For the reasons described above the LEDs have proved the ideal choice for illuminating rooms of growth, when compared with other types of lamps. In particular, the red LED with a wavelength of 640 nm were the most efficient, since their light contributes about 96% of the process of photosynthesis. Experiments have shown that different plant species can be grown successfully with LED light, including spinach, lettuce, radish, wheat and potatoes. In general, for normal growth, is also required on 15% of the blue LED at 440 nm, which allows you to equate the yield obtained with cultures grown with white light.
Some research has demonstrated the need for an intense blue light in the early stage of growth to reduce the 'lengthening hypocotyle. It 'been proven that a percentage of green light may have beneficial effects on growth.
The "Specialized Center of Research and Trainingin Advanced Life Support (ALS NSCORT)" in collaboration with NASA , "Orbital Technologies Corporation (Orbitec)" have developed an array of reconfigurable LED panels can reduce the energy required to grow plants with electric lights.

Each LED panel is a square of 6.25 cm ² composed of 100 LEDs divided as follows:

64 red LEDs at 640 nm
16 blue LEDs at 440 nm
20 green LEDs at 540 nm + 2 photodiodes

The small size of the panel and the proximity of the LEDs allow to obtain a uniform spectrum emitted.
Since the current loop is controlled separately for each color, is the ratio red / blue, that their intensity can be changed continuously.
20 of these panels, LED panels are mounted on a linear (array) 65 cm long. It is placed on top of a box that contains 2 electric fans used to draw air from the bottom to the top of the substrate. This cooling method allows the plants to grow close to the source of light without burning.
Singolo array di pannelli LED
Image taken from the publication "DEVELOPMENT AND TESTING OF AN EFFICIENT LED LIGHTING DESIGN FOR INTRACANOPY Minimizing EQUIVALENT SYSTEM MASS IN AN ADVANCED LIFE SUPPORT SYSTEM."

As can be inferred from the publications and the technical drawing above the size of the LEDs used are extremely small: the red LEDs are arranged in 4 rows of 16 LEDs, and if the side of the printed circuit on which are mounted to the side measuring 2.54 cm The diameter of each LED does not exceed 1.5 mm.

'S array of LED panels are generally placed vertically in the growth chamber and is arranged so that individual panels can be switched in sequence starting with the lower panels to follow the vertical growth of the plant. In this way no energy is wasted, especially in the early stage of growth when the plant is small, allowing you to turn with the right power level only the panels that serve to illuminate the leaves. Intracanopy LED lightsicle array with LEDs off.
The photodiodes are mounted on each panel are designed to detect the proximity of green elements (the plant) so you can automatically manage the lighting of the LED when the leaves are positioned in front of them.

As an alternative to vertical configuration, the array of panels can be arranged horizontally next to each other over the plants, thus forming one large roof panel that makes the growth chamber. This arrangement of the panels is ideal for illuminating the lettuce and wheat dwarf. It is not recommended for plants that grow vertically like beans, because it was observed that these plants tend to grow much at the top dellla growth chamber, next to the LED panels, producing a crop smaller than using the same array LEDs arranged vertically and fed the same amount of energy.

I hope that all this information can the removal of doubt about the real effectiveness of lamps and LED grow to be of help to those who, like me, going to experience them and build them into crops indoors.

Perhaps it might also be interested in these articles:

Better organize your home garden

Gardening can be a very charming work, and like other sciences, a little bit of knowledge can not hurt to start with the foot ...

Redden the lettuce with Ultraviolet LEDs

An experiment has shown that exposure of lettuce increases ultraviolet LED dark pigments of the plant making it more e. .. red

LEDs to grow plants: low power consumption and high efficiency

Use LED lights for growing plants when sunlight is not available? This lighting technology can be very ...

Comments (7) Trackbacks (2) subscribe to comments on this post

Hydro Closet
March 5th, 2010 - 15:51
Really great article - I was heading for a similar article which i Probably will still take a shot at, but from a different angle Slightly. Thanks for sharing this with your readers ... Obviously a lot of others appreciate it too!
(Reply)
Major Wolcott
March 30th, 2010 - 20:55
I recently started making my own solar panels - I used some video guides I Discovered and it's working out great!
(Reply)
Franky-CH
June 14th, 2010 - 20:20
The issue of LED lights is very interesting and a few months in my spare time I started to build the experimental lights LED red and blue, the idea is to get energy-efficient lighting, efficient, durable and above all to develop nn heat.
Finding information is the most complicated thing so I go a little 'attempts to start I'm assembling 2 lamps each composed of 7 experimental power 1w LED red, spectrum ~ 450 nm, 20 lm, this 2 blue 1w, ~ 650nm range, 25 lm (mounted on aluminum structure with function of the heat sink)
By reading this article I see that, with regard to the need of light needed for photosynthesis and plant dela scviluppo to its growth and even the addition of a spectrum green + photodiodes would be useful, indeed comporrebbero the optimal combination.
But my question is this:
in your opinion for each square meter of the surface as is the need for total lumens required in the various spectra, respectively, divided red / blue / green? / fotodoidi? finally be able to grow plants indoors and develop a height of approx. 1.20 ml / 1:50 final flowering?
I read that if the high power LEDs is applied to a particular reflecting mirror, the intensity of the lumen is diverted, concentrated and then multiplied, is not it?
Congratulations for the site and all information released.
(Reply)
- Igor
  June 14th, 2010 - 21:41
  The photodiodes you need if you want to create a series of lights are illuminated in part by following the growth of the plant: light only groups of neighbors led to the leaves.
  Maybe, to begin, a system so complex'd forget.
  For the green lights do not have precise data, they used to have reported a study project (see attached to the post), but should be experienced all over, definitely you need blue and red LEDs.
  If you are building experimental lamps could perhaps be an idea to equip groups of LEDs of a dimmer in order to experiment with various combinations such as blue LEDs can be set with high-intensity light in a growth phase which must then be reduced when increasing the plant blooms red. A dimmer for LED power can be acquired or constructed with nominal cost: instead of varying the intensity of current of the circuit a good technique is to vary the frequency of on / off LED.
  It 'impossible to multiply the intensity with mirrors or white surfaces, the limit may be useful to better distribute the light without losses: you can have the white walls surrounding the cultivation.
  You can find more information in the comments of the article published on LEDs
  I am interested in your experiments, if you want to send me information and pictures well, so you can share the experience on the site, may be of help to others who want to build a LED bulb growth.
  (Reply)
Franky-CH
June 20th, 2010 - 12:06
The argument is all to experience, then go on in my tests, although it will still take some time to verify the results.
As for the blue LED I think we put a dimmer so that you can vary as needed.
With regard to "multiply the intensity" of light I took note of how widespread the seller of this product, it is reflective of shells and you wonder if you think it makes sense to apply them to a facility for illunimazione LED or not.
http://www.xled.it/prodotti/accessori/ # ar03
http://www.xled.it/prodotti/accessori/20-6/1.htm
At the following link
http://www.icmag.com/ic/showthread.php?t=154900
public rather interesting discussion on a growth test performed with the famous UFO-LED lamp
http://www.giardinaggioindoor.it/2008/05/07/ufo-led-e-il-futuro-dellilluminazione-indoor/
Therefore it would seem that the growth of cannabis plants is possible with this technique is always the same issue: how much light the red LED (the ideal seems requenza 630 / 660 nm) is used per square meter? Hence the conclusion seems that it takes 180 watts of LED red / blue poroporzioni 7 to 2, where m / 2 ...
Here I report an interesting site that illustrates the construction of a LED (for aquariums, but the principle is the same) and that might be helpful / incentive for those who want to try these experiments:
http://scriptors.ilbello.com/illuminazione-a-led/index.html
while my system will be documented on a site I'm working on, but unfortunately I have little time disponibiule then nn will be times of the shortest :-|
(Reply)
mark
July 19th, 2010 - 17:12
Anyone know why a percentage need more red light than blue light for a plant properly? I'm Svolvar a thesis on the application design, and OLED will probably be in botany, only that this question can not find an answer ... Thanks momentarily
(Reply)
Tina
November 17th, 2010 - 03:07
Hi, my dear friend
How are you?
This is Tina from BERMU LIGHTING TECHNOLOGIES LIMITED.
We learn your name and address from the http://www.google.com
That we have learnt through you are importers of LED.
We avail Ourselves of this opportunity to write to you and see if we can Establish business relations with you.
We've Been exporter and manufacturer of LEDs for many years.
You can browse our website http://www.bermuled.com for more related products.
If you want to know details of our products price,
please contact me, I will send the price list to you.
Should Any of the items be of interest to you, please feel free to let me know.
I'm looking forward to hearing from you soon!
Thanks & Best Wishes!
Tina
(Reply)