Sorry for being so lazy but are these better for light penetration/lumens per sq ft?
DGS, I do not want to knock the E-P, they are killer fixtures. But in regards to you 1000umol recommendation, (1) 1000W E-P would not hit that mark under the 4' x 6' scenario you described above. If used every 4' x 6', the E-P would throw just under 900umol, 10% lower than what you are recommending. On the other hand, if used every 4' x 4', they would throw over 1300umol.
Ic, when you use the calculator on the epap site , for a 4x16 space with 3 fixtures you get 1007umol
And there is the difference. 4x16=4x5.33 per light, not 4x6.
There’s 3 basic things that make fixtures efficient.
The lamp: how much PAR growlight does the lamp produce (PPF).
The reflector: what’s the percentage of that light that is reflected to the plants.
The driver: how much energy do you need to produce that reflected light.
The ePap is: (2100*0,95)/1060 = 1,88 micromol/W
Next to that there’s a study done by a university in Utah. They tested 20 different brands of fixtures. Ours came out best.
I dont care about efficiency.
Is this thing going to put off more lumens per sq ft?
Is the light penetration better?
Im going to guess no because you steered the question elsewhere?
And how do you keep the heat down without a hood?
Im
Is this thing going to put off more lumens per sq ft?
Well im sold. Thank you DGS .
600 for the best light hood and balast. How can you bear that.
Lumens don't really mean anything... You could produce more lumens in the green part of the light spectrum that are totally useless to the plant. These lamps, and really all you should be concerned about, produce more PAR (ppf). This is a way of saying "more lumens in the places where they count." So if you want a dry answer I think these bulbs put out the same amount of Lumens, more or less, but they offer 10-20% more PAR and less of the light that is produced is lost to inefficiency in the reflector.
DGS is on it though.
As far as the penetration goes... 1000w is a 1000w to the law of squares. These systems are in smaller, open, reflectors designed to utilize cross lighting rather than massive reflectors meant to be smashed on top of the canopy. So while they might have the same penetration they offer better light uniformity at the canopy and plant interior lighting in many situations (multiple lights). The UV-B is nice too come harvest time.
Next to that there’s a study done by a university in Utah. They tested 20 different brands of fixtures. Ours came out best.
DGS, is there an online copy of this study? It would be an interesting read I think.