LED vs vertical HPS (PPF and other things)
- Thread starter Prawn Connery
- Start date
Prawn Connery
Well-Known Member
Yeah, I know. But if I'm going to do this, I want to do it properly. That is, when it comes time to build the vertical system I want.
In the mean time, I think I need to put together a couple of horizontal boards for this 4x2 grow so I can start experimenting.
In fact, my commercial friend says he now wants his new room to be a horizontal set-up, as vertical maintenance is too time-consuming for him. This would give me a chance to try a LED board in my own set-up, and if it works, he would adopt something similar on a larger scale for his own.
The HLG 550 looks the goods, but I'm wondering if I could just buy the parts and assemble one myself a bit cheaper? (It's hard to justify $1K on a 515w board when I could throw a 600w HPS in there for a fraction of the price - the whole point of this experiment is to see if LED can really replace HPS at this stage.)
Maybe something a bit more elongated to cater to a 4'x2' chamber? I know the 550 is suited to a 4'x4' . . . What about 3xQB288 3000K boards mounted side-by-side on a 2'x1' heatsink?
I'd also need something like a QB288 4000K board for my 2.2x2 veg chamber.
What about drivers? I'd like to keep them external (not board mounted) if possible, with a dimming option on the 4000K veg board.
Enigma
Well-Known Member
Run the numbers like I did.
Find people that have journals using the equipment you want to use.
That will give you an idea.
Personally, I wouldn't have spent $200 on two COBs if I didn't know they would outperform HID.
What I'm using should be good for about half of a pound. To do the same with HID I would have to use twice the wattage as more electricity is expelled as waste heat with HID lamps.
If I were you, I'd start with 600W HID over the winter, then phase to LED over the summer. You might even keep your HIDs for the winter as they make great space heaters.
Find people that have journals using the equipment you want to use.
That will give you an idea.
Personally, I wouldn't have spent $200 on two COBs if I didn't know they would outperform HID.
What I'm using should be good for about half of a pound. To do the same with HID I would have to use twice the wattage as more electricity is expelled as waste heat with HID lamps.
If I were you, I'd start with 600W HID over the winter, then phase to LED over the summer. You might even keep your HIDs for the winter as they make great space heaters.
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Prawn Connery
Well-Known Member
Summer's coming up (I'm in Australia) and I would need at least 1.5lb from 8 square feet to make it worth my while. That's roughly what we get in the 3600w (6 x 600w HPS) horizontal system I helped set up and maintain for my commercial mate. Just to clarify, that's up to 24oz from each 600w station, or 8-9lb total every eight weeks.
My numbers are suggesting I need at least 400-500w of LEDs, or 3-4 Quantum Boards - assuming they perform as advertised - to harvest 1.5lb. Does that sound about right?
My numbers are suggesting I need at least 400-500w of LEDs, or 3-4 Quantum Boards - assuming they perform as advertised - to harvest 1.5lb. Does that sound about right?
Enigma
Well-Known Member
I'm not very familiar with the QBs. They do look interesting, the only issue is Bridgelux makes LED strips.
I like the idea of being able to choose spectrum and spread it over the canopy while being able to maintain airflow.
That's the QBs only weakness I can see right now, by looking at the numbers they perform well and people have been using them to great effect.
My idea for veg would be a simple, low-profile, spyder with EBs.
I like the idea of being able to choose spectrum and spread it over the canopy while being able to maintain airflow.
That's the QBs only weakness I can see right now, by looking at the numbers they perform well and people have been using them to great effect.
My idea for veg would be a simple, low-profile, spyder with EBs.
Enigma
Well-Known Member
With the right COBs you could accomplish that with 6-9 of them, depending on wattage and cooling system (passive air/active air or water).
I would suggest running 8 COBs to cover 8 square feet. You might be looking at $600 to do it, you'll need the Vero29C or better.
The kicker?
You could run the emitters up to 560W to accomplish your goal and it won't hurt the emitters like dimming does HID lamps.
You'll also have to run the room a bit warmer, around 80-85. That'll save some dough on AC costs as well.
Enigma
Well-Known Member
My original goal after moving to a more friendly state was a vertical 400W with two plants.
Then I found COBs.
Threw that idea in the trash.
ttystikk
Well-Known Member
She's two steps up a stool in that pic. Each plant is on a 6' tall by 4' wide trellis.
CobKits
Well-Known Member
id say vero C is overkill at 1 cob per sq ft,it has no advantage over cheaper cobs under 40W
wietefras
Well-Known Member
Yeah I like strips better too. Gives you a much more open fixture to let the air through. Although COBs would be my preference for a larger space. Even more open.
QB's also seem very expensive to me. I get the impression that COBs can do the same for half the price.
Prawn Connery
Well-Known Member
It will be well above those temps here in Australia during summer. It regularly gets over 40C (105F) and 45-50C on occasion in the grow room without AC. A lot of Aussie growers simply quit growing over summer, but my vertical set-ups were generally OK, as they had lots of ventilation and coco can handle the heat, unlike other forms of hydro. Yield and, to an extent, quality would obviously be impacted and the plants would stretch a lot, but it wasn't a bad time to grow mostly indicas, as the heat and lack of humidity ensured no chance of bud rot.
Why would I need to run the room warmer with COBs?
I like the vertical trellis idea, but being a purist (LOL!) for me vertical growing with HID bulbs was always about surrounding the bulb with plants to absorb all emitted light. I started off with four plants around a single 600w before settling on 2x600w inline bulbs with six plants being about optimum, depending on strain. I could have up to 8-9 plants at any one time around the bulbs, but never less than six to make use of the 360-degree light.
wietefras
Well-Known Member
Less radiated heat, so the plants won;t heat up so much from being under the COBs and therefore the room temperature can be somewhat higher to keep the plants at a more similar temperature as under HPS. Higher plant temperature increases photosynthesis.
I agree, vertical should be about "encasing" the lights with plants around it to reduce loss of light on surfaces other than the plants. Vertical using a plane doesn't make much sense to me either. Only perhaps if you lack floor space and you do have the height available.
Prawn Connery
Well-Known Member
It's good for using head height. Think of it as a vertical scrog,
VegasWinner
Well-Known Member
I am not a qb person. I created a board similar to the ChilLED boards.
Enigma
Well-Known Member
I agree with you, it would be over powered with anything above 50W, I believe. It would give the most even coverage and with enough height you could run them all at full and let the ladies swell.
Of course, there are so many chips to choose from, then each chip has different CRI...
Yes, QBs do seem to be more costly. I couldn't find out because they were all out of stock so I went with Tasty.
I would run COBs in a larger space for sure.
The EBs will replace my veg fixture, giving me even canopy coverage.
The environment has to have a higher temperature because of the canopy temperature. If it is too cold the stomata won't open, same if it is too hot. Since LEDs don't radiate heat like HID you'll have to save money on AC wether you like it or not. The winter is another story.
He is growing vertically with QBs, I think.
I think he is growing vertically with QBs.
He is one of those guys that doesn't Bro-Science, he finds out the truth for himself. If you listen to him you might learn something.
wietefras
Well-Known Member
Who is?
Organic Miner
Well-Known Member
Hey @ttystikk how do support those lights? How do you move them in and out to adjust the distance? Do you have some sort of rail system?
ttystikk
Well-Known Member
I used a vertical SCRoG trellis system which set the proper distance. The plants were clipped to the panel and the buds got wire tires to keep them from sagging too close.
Here's how the array was mounted;
Enigma
Well-Known Member
I'm sure a cylindrical space could be built with COBs. Maybe a hexagon would be the most efficient shape in that case, there would be a minimum diameter of about 10', in my estimation.
That would be one bad ass op.
In-fact, I'm going to start running some numbers...