What wattage is most efficient?

...and why? here's what I'm thinking; if LEDs are more eficient due to the many points of light, then why wouldn't an array of 150 HPS lamps be the most efficient? Logic would dictate that the more points of distribution you have, the better, due to lack of bright spots and reduction of shadows, yet everybody claims 600s are the best. why? I think i can get more with four 150s than a single 600 watter. will somebody please tell me why I'm wrong about this?
:there is no shrug smiley:

the reason why most people will say that six hundred watters are the most efficient is soley for the fact that 600's have the best lumen per watt ratio, better than say a 1000 watter or a 400 watter..

the difference that you are trying to figure out is light penetration. While you have to keep your plants close to light source, depending on the species you are trying to grow, it would be generally more cost effective to use a 450 watt lamp rather than a 150 watt

it comes down to lumen output vs. the area that you can spread it out. 600 puts out more lumens but covers less area then 4 150's, decreasing the effects, where the 150 puts out less over more area, but less lumen intensity. guess w.e floats your boat

ok but those ratios change drastically once you start factoring for distance from bulb & i can get my canopy as high as 4 inches from my 150 reflector without burning whereas that distance would fry under even a 400 watter. for simplicity's sake, let's say we're on a 4X4 table... you can run 4 150s 6" above the canopy level for roughly 20k lumens, where a 600w lamp has to be approximately 10&1/2" to achieve the same intensity, but I've seen that distance burn plants using only a 400w bulb, much less a 600w! it's all about heat dissipation it seems..

GreenerMan2112 said:

the difference that you are trying to figure out is light penetration. While you have to keep your plants close to light source, depending on the species you are trying to grow, it would be generally more cost effective to use a 450 watt lamp rather than a 150 watt

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ok, that kinda makes sense now. 600s would penetrate better into the canopy, so would be better suited to a staggered canopy but not so well for a SOG of uniform clones cuz they dont require much penetration (insert your favorite joke here.) hmmmm...

bobbypyn said:

...and why? here's what I'm thinking; if LEDs are more eficient due to the many points of light, then why wouldn't an array of 150 HPS lamps be the most efficient? Logic would dictate that the more points of distribution you have, the better, due to lack of bright spots and reduction of shadows, yet everybody claims 600s are the best. why? I think i can get more with four 150s than a single 600 watter. will somebody please tell me why I'm wrong about this?
:there is no shrug smiley:

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you are making a faulty assumption that the efficiency of LED is derived from them being in an array, which is not the case. The power factor which the LED's run at is the primary reason for their energy efficiency, though there are some other more technical contributors as well. Similar in the HID question you post which others answer.

bobbypyn said:

ok but those ratios change drastically once you start factoring for distance from bulb & i can get my canopy as high as 4 inches from my 150 reflector without burning whereas that distance would fry under even a 400 watter. for simplicity's sake, let's say we're on a 4X4 table... you can run 4 150s 6" above the canopy level for roughly 20k lumens, where a 600w lamp has to be approximately 10&1/2" to achieve the same intensity, but I've seen that distance burn plants using only a 400w bulb, much less a 600w! it's all about heat dissipation it seems..

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I'm not so sure of your info concerning distance from the canopy with a six hundred watt light. From the chart in Jorge Cervantes grow bible. It says one foot away 90,000 lumens, two feet away, 22,500 lumens and three feet away from the canopy 9,999 lumens. I have my 600 hundreds about fourteen inches away with no problems. Even four feet away is almost 6500 lumens and so you can see the penetration is much greater with a six hundred than with four 150's...unless you are doing a scrog.

ok got ya. LEDs are more efficient due to the lumens produced per wattage consumed. but i hear that LED generated light doesn't have much carrying power, i.e- ability to penetrate the canopy. this is only hearsay, but ppl say it & i hear it... any truth to that?

this is the chart i used...



and yeah, i quoted figures for 400w bulb, which, as i stated, is the cooler burning of the two.

bobbypyn said:

it's all about heat dissipation it seems..

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thats what it all boils down to...in the end.

bobbypyn said:

ok got ya. LEDs are more efficient due to the lumens produced per wattage consumed. but i hear that LED generated light doesn't have much carrying power, i.e- ability to penetrate the canopy. this is only hearsay, but ppl say it & i hear it... any truth to that?

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It's a little different with led's than other lighting technologies. Leds are really a combination of a driver, diodes (sometimes called emitters), and optics. The led's themselves will have a power rating, which is how much light is being produced, but the direction of that light is really not a concern. The direction the light goes in is the responsibility of the optics, which will be measured in degrees. It is the wattage of the led distributed over the field of the optics that determines the penetration. A 1w led with 30 degree optics will penetrate significantly further than 3w led's with 90 degree optics, just for example. Anyway, well engineered lights will be either made of all 1w's with narrow optics and a lot more diodes, or a mixture of 3w broad angle and 1w narrow optics. Properly designed LED's can match penetration from HID, but they aren't cheap. There is a lot of poorly engineered crap out there masquerading as good grow lights making outrageous claims, claims even proper lights can't make (like a 90w led being the same as a 400w hid, lol).