Going from HPS to LED. Worth it?

Olive Drab Green

Well-Known Member
Your 89 watt cob is not putting out 78 watts of actual light, that would make your CXB3590 88% efficient, at the wattage that your are running you are actually around 50-55% or 44.5-48.95 watts of actual light (which is still better than HPS by far). I don't think anyone here is doubting your lights being able to grow nice weed, but you have a lot of misinformation about your lights, PPFD is relative to area, I can take a 9 watt led light bulb from lowe's and cover a 4 inch by 4 inch square area and get well over 1000 PPFD (for a 16 square inch area) but I can't go around saying my 9 watt led bulb puts out more PPFD than a 1000 watt HPS because the 1000 watt HPS's PPFD is measured over a lot larger area. Your 89 watt CXB3590 puts out 932 PPFD over 18"x18", so to put out that same PPFD over a 48"x48 you would need 7.11 of those 89 watt cob's which would be 632.79 watts. I'm putting out 1050PPFD over 48"x48" with 700 watts so it looks like both of our setups are similar in efficiency...
Doesn't matter about getting as much space as you can with it. I'm condensing my PPFD to a smaller focal point than you, so each of my plants are guaranteed to get the amount of light I need to match one of yours. I only grow two plants in this location at a time. So like I said, for my uses, it adds up to what one of your plants will produce with less wattage.
 

Yodaweed

Well-Known Member
Doesn't matter about getting as much space as you can with it. I'm condensing my PPFD to a smaller focal point than you, so each of my plants are guaranteed to get the amount of light I need to match one of yours. I only grow two plants in this location at a time. So like I said, for my uses, it adds up to what one of your plants will produce with less wattage.
Properly lit space is the main determining factor of yield.
 

Olive Drab Green

Well-Known Member
I don't know how you just assume one of your plants will yield the same as mine with less wattage, for one I just pointed out that both of our lights are of similar efficiency, actually if I did the math mine would come out a few percentage more efficient than yours but I'm not trying to turn this into a pissing contest, another thing to point out is the more cobs/lights you have the better coverage you are going to have which will also increase yield, I'm using 32 cob's over a 4'x8' area inside of a tent so I have really no shadowing and light is shinning down from every angle which makes for great penetration which equals a better yield than if i had fewer cobs with the same PPFD. I grow 1 plant per sq/ft and I also have 1 cob per sq/ft, If I were to only use 1 cob growing 1 plant my yield would not be the same per plant it would be less because of the wasted light whereas when you have many cob's together there is a lot less wasted light.
Look, man. I aporeciate your attempts at helping, but I know what I'm doing. I'm not just being proud, either. I'm saying, watch and learn.
 

BecauseIgotHigh

Well-Known Member
1.6 x .6 x 1.6 tent with 400w cxb3590 3000k... going to up it to 600w. I'll be happy if the buds come out pretty dense. Doesn't matter if the buds ain't coke can size, just need to be really dense. if it doesn't but gives me plenty buds but like larfy, fuck this led shit!
 

a mongo frog

Well-Known Member
1.6 x .6 x 1.6 tent with 400w cxb3590 3000k... going to up it to 600w. I'll be happy if the buds come out pretty dense. Doesn't matter if the buds ain't coke can size, just need to be really dense. if it doesn't but gives me plenty buds but like larfy, fuck this led shit!
Same........
 

Olive Drab Green

Well-Known Member
I never said you didn't know what you were doing, for all I know you're better at growing than me, but in regards to PPFD you tried to compare your 89 watt cob to "slightly less" than a 600 watt hid, but put both of those lights over an 18"x18" area and the 600 or even a 400 would have to intense of a PPFD to even grow. Then you tried to say your 89 watt cob puts out 78 watts of light, no it doesn't its not possible, and if it did somehow put out 78 watts of light your PPFD in an 18"x18" area would be 1560 PPFD. It seems that whenever I comment with facts and point out your misinformation your response is either you know what your doing or what you have works good for you, and I don't disagree with that, but this argument is strictly about your misinformation regarding PPFD and claiming your 89 watt cob puts out 78 watts of light which would make it 88% efficient which I pointed out is actually between 50-55%...
About to order the last T1 I'll need for my closet. After that, there will be no shadowing left in my closet, and my Density for the whole closet will probably be about 900-1000. So for still less than 300w, I can get the PPFD of a 600w HPS in a 4x2 instead of a 3x3. ( 18x18 )x 3 = 54 square inches. So it should cover it all, and more than your HPS for less than half the wattage.
 
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Budley Doright

Well-Known Member
Gee didn't take long to go from one to three

"So, for 400-600w of HID, I'd only need to run one 89w Tasty T1. 1000w, probably two or three. Driven higher, at around 2150mA. The heat will be unnoticeable, and the results will probably make you shit yourself."

I did shit myself....laughing :).
 

Olive Drab Green

Well-Known Member
Gee didn't take long to go from one to three

"So, for 400-600w of HID, I'd only need to run one 89w Tasty T1. 1000w, probably two or three. Driven higher, at around 2150mA. The heat will be unnoticeable, and the results will probably make you shit yourself."

I did shit myself....laughing :).
I only need 3 for the area coverage. Not to achieve the PPFD. Still less than half the wattage a 600w would use for the same photosynthetic photon flux density. In fact, more than because it covers 54 square, not 48 square.
 

a mongo frog

Well-Known Member
With 3 of those lights in a 2'x4' closet your PPFD will be 786, now here's the math! 1 of your lights in a 18x18/2.25 sq.ft. area puts out 932PPFD which is 20.71 PAR watts per sq.ft. (932 divided by 45 =20.71) now multiply 20.71 PAR wattsx2.25 sq.ft and you get a total output of 46.6 PAR watts, that's your actual light output measured in watt's of each of your cob's not 78 as you said before. This makes your cob's roughly 52.4% efficient by the way... Ok so you have 3 cob's now so 3x46.6 PAR watts = 139.8 PAR watts covering a 2'x4' area or 8sq.ft so we divide 139.8 PAR watts by 8 sq.ft and we get 17.475 PAR watts per sq.ft, now to figure out PPFD we multiply 17.475 PAR watts by 45 (that's the PPFD formula in case your wondering where the hell 45 comes from) and we get roughly 786 PPFD, not 900-1000PPFD

Now let's compare it to a 600 watt HPS, the best HPS bulbs are up to 40% efficient, but lets say we only have a generic one that was already used for a grow, so we'll call it 30% efficient ok? And we'll cover the same area as your 8 sq.ft... So 30% of 600 watts gives us 180 PAR watts total. 180 PAR watts divided by 8 sq.ft = 22.5 PAR watts per sq.ft. and our PPFD formula tells us 22.5 PAR watts per sq.ft multiplied by 45 gives us roughly 1,012 PPFD. Now if it were a brand new top of the line HPS bulb never used we'd be closer to 1,350PPFD. You actually need close to 4 of your cob's to equal the 600 watt HPS, which is still great because you'd only be using 356 watts which means you'd only be using around 60% of the watts for the same PPFD.
Nice math...... Is all that info on this site? Holy fuck!!!!!
 

Olive Drab Green

Well-Known Member
Bullshit. How can the PPFD go DOWN if the lights more than fill the area? You guys really don't know what you're talking about. In any case, I know I have all I need, so you guys are just going to have to wait several weeks before I thoroughly humiliate you with my outcome.
 

a mongo frog

Well-Known Member
Bullshit. How can the PPFD go DOWN if the lights more than fill the area? You guys really don't know what you're talking about. In any case, I know I have all I need, so you guys are just going to have to wait several weeks before I thoroughly humiliate you with my outcome.
Your lighting is great!!! Now just need some plants!!!!!
 

Olive Drab Green

Well-Known Member
See, if each of my lights averages about 900, plus crossover, and each fixture fills an 18x18, and I have 3, and my closet is only 4x2, I'm actually saturating my closet with more light than it has capacity for, causing reflection from the walls as well. I'm easily going to be between 900 and 1000. PPFD can't go down if the capability exceeds the area given. So fuck all of you.
 
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