PPFD, Light Efficiency & Energy Consumption

So I am a straight up newbie.
South Africa has just decriminalized so its a beautiful state of euphoria I want to turn into some beautiful buds of flora. I have seen many responses in terms of calculating PAR Watts, PPFD and energy consumption. However, I haven't managed to come across a site/thread that could explain the calculations:

My system so far is:
Tent Dimensions: 1,2m wide x 0,6m deep and 1,8m high {reason for rectangle is due to space}
Lights: Cree CXB3590 (3500k) 80 CRI x 4 {glass lens}
Driver: Meanwell HLG-185H-C1400B
Hydroponics {Bubbleponics}
Price per kwh = R1,70

I am looking at calculating the PPFD of my system and running costs of my system (excluding the bubbleponics). Please can some one show the calculations as well as the answers or a link to where these calculations can be obtained. My thesis is based on it so this will be hugely appreciated.

Happy Growers Days!

Im lame and lazy so I don't know the math involved. But there is a thread here

https://www.rollitup.org/t/diy-cob-led-calculator.890214/

Which has a download for a cob calculator, if you look at the first post the dude has the latest links in his signature.
If it still downloads it will give you info like this... (you need java)


CXB3590CD36V3500K 4 COBS @1.4A ON 1.813 PROFILE HEATSINK
8 SQ.FT. CANOPY 95% EFFICIENT DRIVER @1.7 CENTS PER KWH
Total power watts at the wall: 205.26
Cobs power watts: 195
Total voltage forward: 140
Total lumens: 35595
Total PAR watts assuming 10% loss: 99
Total PPF: 460.35
PPFD based on canopy area: 619.4
PAR watts per sq.ft.: 12.38
Cob efficiency: 56.34%
Power watts per sq.ft.: 24.38
Voltage forward per cob: 34.89
Lumens per watt: 182.54
Heatsink riser thickness / number of fins / fin's length: 0.3in/6/0.95in
Heatsink area per inch: 100.94 cm^2
Total heat watts: 85
umol/s/W / CRI: 4.65 / Estimated
Heatsink length passive cooling @120cm^2/heatwatt: 101 inches
Heatsink length active cooling @40cm^2/heatwatt: 34 inches
COB cost dollar per PAR watt: $1.92
Electric cost @12/12 in 30 days: $1.76
Electric cost @18/6 in 30 days: $2.38
Cost per cob: $47.62
Heatsink cost per inch cut: $0.66
Total cobs cost: $190
Total heatsink passive cooling cost: $67
Total heatsink active cooling cost: $22

I used your info to generate the above, just replace the dollar sign.
Hope that helps, there are others who will explain the math.

Hope this helps your cause:

For 7.750016sqf, used for 18.0 Hours a day, using 4.0 LEDS running at 50.4 watts with an efficacy of 2.25 pf
TOTAL LED PPF output of 453.59999999999997 μmol/m^2/s in a space of 7.750016 ft^2 or 0.719999736448 m^2.
Daily Light Integral (DLI) @ 1ft = 41 mol.
Totaling at 26 Watts/ft^2.
Total Power consumption = 201.6 Watts. Monthly power consumption = 110 kwh.
AVG PPFD @ 1.0ft = 630 μmol
AVG PPFD @ 1.5ft = 294 μmol
AVG PPFD @ 2.0ft = 173 μmol
AVG PPFD @ 2.5ft = 116 μmol
AVG PPFD @ 3.0ft = 84 μmol
Last 4 PPFD Values added value to take Reflectors into the equation.

cheers!

eyderbuddy said:

Hope this helps your cause:

For 7.750016sqf, used for 18.0 Hours a day, using 4.0 LEDS running at 50.4 watts with an efficacy of 2.25 pf
TOTAL LED PPF output of 453.59999999999997 μmol/m^2/s in a space of 7.750016 ft^2 or 0.719999736448 m^2.
Daily Light Integral (DLI) @ 1ft = 41 mol.
Totaling at 26 Watts/ft^2.
Total Power consumption = 201.6 Watts. Monthly power consumption = 110 kwh.
AVG PPFD @ 1.0ft = 630 μmol
AVG PPFD @ 1.5ft = 294 μmol
AVG PPFD @ 2.0ft = 173 μmol
AVG PPFD @ 2.5ft = 116 μmol
AVG PPFD @ 3.0ft = 84 μmol
Last 4 PPFD Values added value to take Reflectors into the equation.

cheers!

Click to expand...

Gents, thank you.
I just want to confirm the AVG PPFD @ 1.0ft and so forth is the distance (height) below the lights?

The 1 foot figure is accurate, but the others past that point are only estimates! In reality, you should be getting much more light that those distances... We've seen many posts here where we actually find that we get much more light in lower locations than we what we calculated.