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So I have 200w of CFL lighting going on 4 plants to cover approx. 3 square feet.
Question: Would my yield increase if I used a 150w HPS instead to flower?
Also, if I went up to a 250w hps would that double my yield for just another 100 watts? Say 6 square feet instead of 3.
And how much power do all these different lights actually pull when you include the ballast?
When you say 200watt CFL do you mean real watts or incadecent equivalent? I suspect you mean you have 2-25Watt CFL's that equal 200watts of incadecent lighting, if that is the case you are only using 50 watts of electricity not 200 watts.
Now if that is the case the HPS is the way to go, A 150w HPS will do well for that space but you have to have some ventalation to get rid of the heat produced by the light. Plus that is real wattage, but really nothing to worry about it will cost about $0.25 a day to run at 24/0.
Hope this helped and GL and Happy Growing
Hey Jerry what's up, we went over that in another post, but no worries.
It's 900W of incandescent equivalent, 200 real watts of CFL.
So what'ya think?
Do you know how many lumins?
A 150watt HPS produces between 13,000 to 15,000 lumins. What are your CFL's producing?
Sorry did not see the 250 a 250 watt HPS produces 25,000 to 28,000 lumins
My first post! :)
200w of CFL is fine for flowering in 3 square feet. (And I'm guess that you're using typical CFLs, which means you're getting around 14,000 to 15,000 lumens.) You'll see a lot of different information about the amount of watts or lumens per sq. ft. A lot of it will be good, but you need to be more specific about some things. The big question is--How far from the plants are my lights? You need to keep CFLs close to plants--less than 3" all the time; half that is preferable. An HPS will seem to produce as much or more light, even though it is rated for fewer watts...but that's because it's rated for watts at a certain distance (usually 8"-1'). If you have your HPS farther from your plants than this, you'll start to lose watts. Still, HPS is generally going to increase your yield because of light intensity...HPS lights penetrate the canopy better than CFLs do. But you also get more heat, which can result in more stress and ventilation issues.
If you go with CFL's, do two things. One, get reflectors. Use the lumens your bulbs are putting out. Two, try putting one or two in an area where they get under the canopy. You'll get better growth below and your buds will fill out better. HPS is simply more powerful, but you can make adjustments with CFLs to increase your productivity. Good luck!
Hi Roughrider, good to see you posting, thanks for the info.
Question: as far as heat goes, many people seem to believe that the watts is what determines the total heat. So I wouldn't get more heat to remove from the grow, it's just that the HPS puts out all the heat from one single point and therefore must be further from the plants. This supposedly is some kind of physics rule...
Make sense to you?
Ohh, and by the way, any idea how much yield would increase with the 150w HPS?
Heat is generally caused by production of light. And production of light (which is measured in lumens) and watts (which are a measure of power) aren't really related. So wattage doesn't directly affect heat...think of it like this. A 150 watt incandescent bulb uses the same amount of power as a 150 watt HPS bulb. But the HPS bulb is much hotter. That's because it's energy usage is more efficient; it's creating a lot more lumens than an incandescent bulb of similar wattage. Direct light is what causes heat. We think of air as solid, but it's composed of millions of molecules. When light waves (energy) strike these molecules, the molecules move more quickly, and the air gets warmer. More light = more energy = more movement = more heat. When light energy strikes plants, the plants absorb it and convert the light energy to heat and chemical energy for photosynthesis.
CFL's have a larger surface area for heat dissipation, so you're pretty much on about the light coming from a single point creating more heat. And most CFL's are slightly less efficient at converting energy to lumens than HPS bulbs. A 150 watt HPS bulb will produce about 15,000 lumens; a 23 watt CFL produces about 1650. 6.5 of those 23 watt bulbs would take 150 watts of energy, but only produce about 10,750 lumens. So HPS is hotter because it has less area for heat dissipation and is more efficient at producing lumens. Got it?
You really need at least 2500 lumens a sq. ft. to grow decently; over 4000 is a lot better. A 150w HPS, like I said, will produce about 15,000 lumens. You could get a marginal 6 sq. ft. grow with it, or a pretty good 4 sq. ft. grow with it. 200w of CFLs will probably give you about the same amount of lumens. The CFLs will be cooler so you will have less problem with heat; they are less efficient, so you won't get the light depth into your plant.
That's enough math and science for now. It's just my opinion, but a lot of bad grows have to do with wasted light. CFLs with reflectors shine light in all sorts of places where you don't necessarily want it. IMO, a good CFL grow with reflectors isn't much worse than an HPS grow, although it will take more CFL watts to produce the same amount of energy. You're going to get bigger yields with HPS...maybe 25-50% more than a well done CFL grow; more than twice as much as a grow done with lousy CFL placings and no reflectors. But you also have more issues with heat, strewss, and ventilation...and in a small areas, that can be a deal breaker. So it's up to you, man.
Great job explaining the differance.
Thanks,
Thanks, great info.
Check out the link to my grow log below, it has just a few pictures where you can see the lights. All bulbs have reflectors and all bulbs are 1 to 3 inches above the tops. Also, the walls are lined with reflective insulation material and are very close to the plants so the light doesn't have to travel very far when reflected. Not sure what else I can do, I guess I feel pretty good about it, especially with the continued LST that keeps all main tops very close to the lights.
Still, if I could really get 25-50% more by using a 150w HPS which actually uses slightly less power then that sounds like a bargain and I will probably do that eventually.
Anyway, in a month or so I guess we'll know exactly how much I got. At least pretty close though I don't own/need a scale.
Lastly, I'm planning for my next grow to be in a Hempy Bucket (passive hydro). I wonder how that would do with the 150w HPS / Hydro combination!
If you don't know what a Hempy grow is check this out or just Google "Hempy Grow".
HomeGrown420 - The Hempy Bucket
Hempy Bucket eh, thanks for the great link...ima give that a try also
peace
You really need at least 2500 lumens a sq. ft. to grow decently; over 4000 is a lot better. A 150w HPS, like I said, will produce about 15,000 lumens. You could get a marginal 6 sq. ft. grow with it, or a pretty good 4 sq. ft. grow with it. 200w of CFLs will probably give you about the same amount of lumens. The CFLs will be cooler so you will have less problem with heat; they are less efficient, so you won't get the light depth into your plant.
Hey Bro, Great information and i am new to the site. I just want to get your opinion on a grow system i have (first time grower). I have a bubbleponic system in a 32X64X24 grow hut i am running two 6" fans with 455 led lights rated at 54 watts and 2 23 watt cfls. (100watt replacments). i am running about 80 degrees and about 60% humidity. I havent planted yet due to i want everthing perfect and running smoothly.(i have 6 5 inch plants outdoors right now) im going to transplant soon and was wondering if my lighting if enough to produce good plants. Any info would be greatly appericiated. thanks alot
Just a quick question for you are those 6" fans inline duct fans, venting out of the tent or just oscilating fans circulationg the air?if they are vented out and your geting 80 degree temp with nothing growing or running. you can expect your temps will definately rise once you do get the grow going.
:stoned: