A NGO in the poorest neighbourhood in Denmark need your expertise!!

[fluid00]

Hi guys,
I am the founder of a NGO in the "ghetto" in Denmark.
One of the things that I am trying to do is to establish a small hydroponics project where we are experimenting with growing leafy vegetables(salds, herbs) in a stacked hydroponic system,
We have been successful enough to get some funding, and are now trying to figure out what lights to use. Also I am very concerned with how on earth we are going to waterproof - because in a stacked system that seems very prudent.

Our system is being built like the image attached

(0,7m wide / 3m length - approx 2fx10f)

So I have been looking into buying boards from Kingbrite/Meiju since we do not have the means to buy the more expensive stuff. As Kingbrite seems to be better with warranty related issues, I have mostly been looking there. But I am seriously in doubt as to how many light I would need per row, and what to choose. Maybe you guys can offer me some advice, as I know I am a bit out of my depth here! (With no experts at hand)
Currently I am wondering which way to go. QB boards or strips, as the boards bought in bulk seems to be best value. Here is the three different systems I have looked at:

1)QB boards
https://www.alibaba.com/product-detail/ ... creen=true
2) Thick green strips
https://www.alibaba.com/product-detail/ ... creen=true
I think these offer rather good value for the money. But I am still very much in doubt. I am very aware that if I spend my money the wrong way - well the project will suffer, and my duty towards these kids would not be fulfilled properly.

3. Any other systems? Maybe you guys have suggestions? (again the size of each system is 0,7m wide / 3m length - approx 2fx10f)

I hope you will give me a hand here

[TEKNIK]

My suggestion is to use 2 rows of bridgelux gen3 4000K CRI90 per shelf, the CRI is important. 2 rows running at 150W per shelf is about the right amount of light for herbs, space them 150mm from the edge of the shelf to get even coverage.

I would also suggest placing the strips into a housing to protect them

I do have a very easy to install product solution for what you are doing, price is alot higher than using bare strips as mine comes in a protective housing with optics
Mine is a custom spectrum CRI95 4000K designed to be used exactly the way you are going to be growing herbs. Price is about $200 per shelf which maybe over your budget but they do have thier own housing and will last a very long time in comparison to standard strips.

https://www.slip.farm

These guys use my custom cri95 chips, you can see they grow pretty much everything under one full spectrum.

[fluid00]

I thought I needed much more watt per foot for leafy greens? I read somewhere that about 30w per sqf.?

In terms of money they are ofcourse extremely tight. Also the board is somewhat asking me to do this cheapest way possible. Using strips as you suggested is definitely a much better way forward than qb boards.

I am so thankful for your guidance. At least I know which to go now. I may return when I figure out what kind of money I am permitted to use.

[PeteR_1]

Some Calculations...
3.0 m x 0.7 m = 2.1 sq m (m2)


Recommendation based on PPFD and Efficient LED (Strips and Boards):
1... @ 20 PPF (per 0.1 sq m Seedlings, Cuttings @ 200 PPFD) * 21 = 420 PPF
420 PPF / 2.5 PPE(PPF/W) = 168 Watts
420 PPF PPF / 72 PPF each (BXEB-L1120Z-35E4000-C-C3, Gen3 1120mm) = 6 strips (162 Watts)

2... @ 40 PPF (per 0.1 sq m Vegetative growth @ 400 PPFD) * 21 = 840 PPF
840 PPF / 2.5 PPE(PPF/W) = 336 Watts
840 PPF PPF / 72 PPF each (BXEB-L1120Z-35E4000-C-C3, Gen3 1120mm) = 12 strips (324 Watts)

3... @ 60 PPF (per 0.1 sq m Late Veg. - Flowering @ 600 PPFD) * 21 = 1260 PPF
1260 PPF / 2.5 PPE(PPF/W) = 504 Watts
1260 PPF PPF / 72 PPF each (BXEB-L1120Z-35E4000-C-C3, Gen3 1120mm) = 18 strips (486 Watts)

4... @ 80 PPF (per 0.1 sq m CO2 Enhanced Flower @ 800 PPFD) * 21 = 1680 PPF
1680 PPF / 2.5 PPE(PPF/W) = 672 Watts
1680 PPF PPF / 72 PPF each (BXEB-L1120Z-35E4000-C-C3, Gen3 1120mm) = 24 strips (648 Watts)
[Note; 2.5 PPE = 167 Lm/W * 0.015 (Generic 4000K, 80 CRI PPF/Lm factor)]
Light Sizing Chart... download/file.php?id=4438&mode=view

PPFD (umol/s/m2) relative to CO2 Limited Photosynthesis Chart

[Note: ~ 500 PPFD (umol/s/m2) is "maximum" Photosynthesis without added CO2 (CO2 Limited) and,
Adding CO2 at 500 PPFD produces much higher Photosynthesis than only increasing PPFD (to over 800 umol/s/m2)]


Selected Drivers, Dimmable:
1... HLG-240H-42AB = 1 @ 162 (Adj.) = 162 Watts * 2.7 PPE (6 - BXEB @ 27.0 watts each strip) = 437 PPF
XLG-240-H-AB = 1 @ 162 (Adj.) = 162 Watts * 2.7 PPE (6 - BXEB @ 27.0 watts each strip) = 437 PPF

2... HLG-320H-42AB = 1 @ 320 = 320 Watts * 2.7 PPE (12 - BXEB @ 26.6 watts each strip) = 864 PPF
HLG-240H-42AB = 1 @ 240 = 240 Watts * 2.7 PPE (12 - BXEB @ 20.0 watts each strip) = 648 PPF
XLG-240-H-AB = 1 @ 240 = 240 Watts * 2.7 PPE (12 - BXEB @ 20.0 watts each strip) = 648 PPF

3... HLG-240H-42AB = 2 @ 240 = 480 Watts * 2.7 PPE (18 - BXEB @ 26.6.0 watts each strip) = 1296 PPF
XLG-240-H-AB = 2 @ 240 = 480 Watts * 2.7 PPE (18 - BXEB @ 26.6.0 watts each strip) = 1296 PPF
[Note; XLG Series Drivers are also most cost effective at lower PPFD requirements...]


BXEB Gen3... https://www.bridgelux.com/sites/default ... ev%20A.pdf
HLG-320H-42B... https://octopart.com/search?autosugg_id ... 2b&specs=1
HLG-240H-42B... https://octopart.com/search?q=hlg-240h- ... SD&specs=0
XLG-240-H-AB... https://octopart.com/search?autosugg_id ... ab&specs=1
Fluence Photobiology Guide... https://2xuwao2gok1v2wn2em9n5ys8-wpengi ... e-2019.pdf

[fluid00]

Wow!!! Thank you!

That was such an informative and kind answer. I don't understand all of it yet - but I will do my best to figure out. Thanks for the links to ressources, they will come in handy when we get further.

I am very very grateful.

Kim.

[PeteR_1]

You're welcome.

IMO, 240 - 320 Watts per shelf is more than adequate to provide the recommended target DLI of 12 - 18 (mol/m2/day).
e.g., @ 240 Watts * 2.5 PPE = 600 PPF
PPFD Calc... 600 PPF / 2.1 Sq m (m2) = 285 PPFD
DLI 12 Hr Photo-period... 285 PPFD * 12 Hrs * 0.0036 = 12.3 mol/day
DLI 18 Hr Photo-period... 285 PPFD * 18 Hrs * 0.0036 = 18.4 mol/day

Target DLI (mol/m2/day) for Plants

Simple DLI formula for Single (Sole) Source Light;
PPFD * Hours * 0.0036 = DLI
e.g., [300 umol/m2/s * 16 Hrs (Photo-period) * 0.0036 (umol/mol) = 17.28 (mol/m2/day)]
e.g., [DLI 30 / 0.0036 ] / 600 umol/m2/s (PPFD) = 13.8 Hours (Photo-period).

Target DLI... https://gpnmag.com/wp-content/uploads/2 ... N_0519.pdf

Cornell Univ. Hydroponic Crops... http://cea.cals.cornell.edu/crops/
Cornell Univ. Leafy Greens... https://cpb-us-e1.wpmucdn.com/blogs.cor ... Greens.pdf
"When DLI is maintained at 17 mol·m-2·d-1, 5- to 6-ounce heads are ready to harvest 24 days after transplanting... We have not experimentally researched optimum light and temperature but have found good performance with a DLI of 17 mol·m-2·d-1 and day/night temperatures of 75/66° F..."

[fluid00]

Today I got the first picture of the build:

So I am listening to the advice and contemplating buying 18 strips(1120cm) for each row. However right now I am wondering if it would make more sense to buy 36x 590cm strips and mount them horizontally instead?

Now that I have to buy at least 324 520mm strips(108 per system. I have 3x systems), I might aswell buy custom made covers that are waterproof. Thinking of something like this:

https://app.alibaba.com/dynamiclink?tou ... cene=buyer

Just wondering, if I have to many strips on each shelf could I just dim them to hit the target DLI? Sorry I am such a noob here. Kinda of just learning while I go along.

[PeteR_1]

You could get free professional light planning from several manufacturers, e.g., LED Strip equivalents L-Series or C-Series from Valoya... https://www.valoya.com/light-planning/

An example of Light Plans from Valoya Brochure; Cannabis-Solution-Guide-2019

The Valoya Brochure... https://www.valoya.com/wp-content/uploa ... 2019.1.pdf

[fluid00]

72 PPF each (BXEB-L1120Z-35E4000-C-C3, Gen3 1120mm)
Where did you get the 72 PPF each? Is it something you can calculate somehow?

[PeteR_1]

72 PPF each (BXEB-L1120Z-35E4000-C-C3, Gen3 1120mm)
Where did you get the 72 PPF each? Is it something you can calculate somehow?

Yes its calculated using a "Generic" Conversion Factor [0.015 PPF/Lm * 4800 Lm = 72 PPF]

viewtopic.php?f=15&t=5756
Generic for White PC LEDS - Lumens to PPF (PPF/Lm) Factor:
0.014 = 5000K 80 CRI Cool
0.015 = 4000K 80 CRI Neutral
0.016 = 3000K 80 CRI Warm
e.g., 20000 Lux * 0.015 = PPFD 300 umol/s/m2

The formula to convert Lumens (or Lux) is;

PPF (umol/s) = Lm * PPF/Lm factor

PPFD (umol/m2/s) = Lux * PPF/Lm factor




e.g., A Conversion Factor for 4000K Samsung (Lm301B / H) is 0.0144 PPF/Lm
You just have to calculate the total Lumens output from the single strip or fixture, can also be based on Lumens per Watts, then multiply by the conversion factor.

From the Samsung Engine Calculator...

5748 Lm (@ 30 Watts) * 0.0144 = 82.77 PPF

45985 Lm (@ 240 Watts) * 0.0144 = 662.18 PPF

178.1 Lm/W * 0.0144 = 2.564 PPE [PPF/W (J)] System Efficacy

200 Watts * 2.564 PPE (PPF/W) = 512.8 PPF


The actual height above the canopy has to be measured and can be configured by;
1. Spreading out the strips to create a uniform canopy over the actual grow area or
2. Creating concentrated “Bars” of light for greater intensity, similar to Linear LED High Bay fixtures.
Note that the output from LEDs without Lenses can be calculated at 100% towards the canopy although there will be some losses due to the 115 - 120 degree (wide) Beam angle.

BTW, One (1) BXEB-L1120Z-35E4000-C-C3 is comparable in PAR output to one (1) Valoya Model L-35 (@ 73.5 PPF), two (2) Strips are comparable (in PAR output) to one Valoya Model C-75 (@ 144 PPF).