HID-LED side by side comparison

[stonedrone]

I'm not trying to imply anything here as to which lighting system I think is better. I found this looking around online and figured I would share it with everybody here. What I found most interesting was the difference in grams per Kwh. The test was done with a 400w HID and an 82w LED. I was not amazed by the findings, but it was interesting and the first time I saw any kind of side by side like this.

hxxp://www.420magazine.com/forums/420-grow-videos/75830-comparison-led-vs-hid-lights.html[/URL]

 

[Disco94]

I will be buying a 90w LED UFO soon for a 3x3 area in the attic when it cools off. Gonna be throwing 9 fem. AK47xBlueberry Autos in there with my organic soil mix. Hope to get 2 crops out before it warms up. Let ya know how it goes since a lot of people are curious about the new LED craze.

 

[JustAnotherAntMarching]

Check my journal and you may change your mind about just 1 UFO for a 3x3.... IMO it wont be enough light... also what about the first 3 weeks of veg on the auto Dicso??

 

[Rolling Thunder]

An interesting clip, to say the least. Thanks stonedrone. In terms of the final yields, I confess to being unimpressed by both; but that probably says something more about the grower's ability, than about anything else. For example, the height of the LED was way too high at the start of the grow; though eventually lowered and kept closer to the canopy.

Since they were clones of the same strain grown on both sides, it seems a little odd that the LED light took an extra 14 days to finish the buds. It's hard to make a call on that without having more information, but it seems to point toward an inadequate red-light spectrum, or perhaps too much blue-light in relation to red.

At .36g per watt, it would have taken 252 watts of LED to yield 91 grams like the HPS grow. Like BBFan asked elsewhere, what if we were to match 400w of LED against 400w of HPS. I think it is clear from this test grow how that match would fair in the end. Don't you guys? - RT

 

[StoneyBud]

Interesting test. It's results match the results of every test I've read or seen.

I've noted some very obvious problems with the LED grows. First, the manner in which the plants themselves are grown. The LED lights have virtually no penetration of usable light below 18". It's MANDATORY that the lights be used on plants that are either very short at maturity or grown in a manner that negates this problem, such as a center cola grow only.

I believe that had a center cola only grow been done, and the space in this test been filled to capacity with those center cola plants, (about 6), the end weight would have been reversed with the LED far outweighing the HID light grow.

I'll be proving that on my next grow that will start as soon as I have enough clones from my host plant.

The test shown, isn't really a fair yield test for that reason. The limitations and benefits of the two lights are not balanced for a yield test.

The test is "How much weed can you grow in this amount of space". It's not "Using exactly the same parameters that work for a HID, we'll see how a LED compares". However, the latter description is exactly what has been done.

Kudos to the guy setting up the experiment. He's on the forefront of LED marijuana testing, but needs to refine his testing to fit the end result that is being desired, YEILD IN AREA, being that end result.

Had either small auto-flowering strains or center cola plants grown on an immediate 12/12 schedule, I believe the test results would have shown WAY different results.

Lets take as an example, both the standard and robotic vacuum cleaners available on the market.

A standard vacuum can be used manually to pick up a 5 pound bag of cat food from a carpet by jamming it into the pile repeatedly until the pile is gone.

The little robotic vacuum can't do that. However, if that 5 pounds of cat food is spread in an even layer, one deep, and the robotic vacuum is emptied when full, then it will pick it all up.

The end result of "Will each vacuum pick up cat food from a carpet" testing is done with identical results.

The end result of "Will each vacuum pick up debris in an identical fashion" shows the manual vacuum having an advantage when the test is done in a manner that allows for it's obvious ability to compenstate for debris height via human intervention.

It's all in how the test is performed.

Thanks for the great test you've found, Stonedrone. Watch for my test that will be starting somewhere around December. My grow area will be ready in Mid October, but my host plants won't have enough cuttings available by then, I don't believe.

 

[Rolling Thunder]

Great observations, there, StoneyBud, and I quite agree with them. I'll be closely following your LED test grow. Should be both exciting and very informative, I trust. - RT

 

[Growdude]

I believe that had a center cola only grow been done, and the space in this test been filled to capacity with those center cola plants, (about 6), the end weight would have been reversed with the LED far outweighing the HID light grow.

Even if the HID was grown the same way?, center cola , 6 plants?

I highly doubt that the LED side would produce more.

 

[Rolling Thunder]

Good point, Growdude. I should clarify my meaning, in light of it. I didn't mean I thought the 82w of LED would've produced more overall dried bud than the 400w HPS, in the same area, but only that the grams per watt spread would have been even greater, in favour of the 82w LED. - RT

 

[StoneyBud]

Even if the HID was grown the same way?, center cola , 6 plants?

I highly doubt that the LED side would produce more.

Perhaps you're correct, but here's the real consideration; the LED side would have been close to the same in yield and the output in grams per/watt of electricity would have SMOKED the HID.

The goal here is to have a grow that uses about 1/10th of the electricity, produces virtually no heat and minimizes costs to produce the weed in near identical yields.

No cooling hoods. No fans, No ventilation except for that needed to provide fresh oxygen and CO2, 1/10th of the electric usage.

If it works as I think it will, it will be a "hands down" win for LED's.

In fact, I think there may be a chance that the LED's *WILL* produce more than HID's in the same scenario. We'll see on my next grow.

I'll be using 200 watts of LED's over an area I usually cover with 860 watts of HPS. The area is 3.5 x 5.5 feet. This will be an 80% electric savings from only the lights. This won't count the automatic savings of air-conditioning, cooling fans and ventilation costs for cooling.

As a result of having no heat to deal with, and the shorter grow, I intend on my second crop of LED grown weed to use two levels in the same area. This will double the grams per/sq ft produced by my first grow and will be an impossibility to reproduce using HID's.

At that point, I believe that the LED's will FAR out produce the HID's in both grams per/watt and grams per/area.

I wish I could start it right this minute....hehe

 

[Growdude]

LED'S are out producing HID'S gram per watt now, and I agree that could probably be increased.

For me grams per sq/ft are whats most important as I am in a situation where I do not have to pay for electricity, just indirect costs i suppose.

Looking forward to your stadium LED grow S.B.

 

[Rolling Thunder]

For me grams per sq/ft are whats most important

According to the results of this particular HPS/LED comparison grow, 400w of LED would have produced 144g to the 91g of the 400w HPS. Make the recommended adjustments and that spread only increases. - RT

 

[StoneyBud]

LED'S are out producing HID'S gram per watt now, and I agree that could probably be increased.

For me grams per sq/ft are whats most important as I am in a situation where I do not have to pay for electricity, just indirect costs i suppose.

Looking forward to your stadium LED grow S.B.

Thanks Growdude! It won't be a stadium grow really. It will be one level directly over the other in an area with an 8 foot ceiling.

The panels are only 2 inches thick. I'm going to build a frame that will have a hydro ebb and flow tray supported right above the bottom lights.

I'm going to use 4" trays with remote reservoirs. Should be interesting.

The first grow will be to "size" the grow with one level. I'll work out the bugs on that one.

 

[StoneyBud]

According to the results of this particular HPS/LED comparison grow, 400w of LED would have produced 144g to the 91g of the 400w HPS. Make the recommended adjustments and that spread only increases. - RT

OMG! Imagine 400 watts of LED's in that little area! It would have been like looking at the sun. Yikes!

 

[Rolling Thunder]

OMG! Imagine 400 watts of LED's in that little area! It would have been like looking at the sun. Yikes!

I confess a desire to see such a side-by-side comparison done, though I'm persuaded that with everything perfectly dialed-in, it would not take 400w of LED to surpass the 400w HPS yield per sq. ft. I suspect also that with 400 w of LED in that small area, the point of light saturation might be reached well below the 400w marker, and that any extra light beyond that saturation point could be effectively wasted, without increasing the CO2 level.

 

[Growdude]

Thanks Growdude! It won't be a stadium grow really. It will be one level directly over the other in an area with an 8 foot ceiling.

The panels are only 2 inches thick. I'm going to build a frame that will have a hydro ebb and flow tray supported right above the bottom lights.

I'm going to use 4" trays with remote reservoirs. Should be interesting.

ok I think I see what your doin.

Could you flood the bottom tray by letting the top flood the bottom tray and use only one rez?

You could use actuated valves off of timers to control the flood time of each tray.

 

[Growdude]

At .36g per watt, it would have taken 252 watts of LED to yield 91 grams like the HPS grow.

Thats a little more than half the wattage for the same grams, not bad at all.

I just dont like some of the claims by these LED light manufacturers that a 90 watt LED light will perform as well as 400 watts of HID.

 

[StoneyBud]

I confess a desire to see such a side-by-side comparison done, though I'm persuaded that with everything perfectly dialed-in, it would not take 400w of LED to surpass the 400w HPS yield per sq. ft. I suspect also that with 400 w of LED in that small area, the point of light saturation might be reached well below the 400w marker, and that any extra light beyond that saturation point could be effectively wasted, without increasing the CO2 level.

I'm not sure that a saturation level would be reached. Marijuana is such a fast growing, light utilizing plant, that with a nutrient supply and oxygen/CO2 supply matching the plants usage capabilities, I think it may only grow at an unprecedented rate and density.

I will be testing this until I get it maxed for yield per/watt and yield per/area/volume.

 

[StoneyBud]

ok I think I see what your doin.

Could you flood the bottom tray by letting the top flood the bottom tray and use only one rez?

You could use actuated valves off of timers to control the flood time of each tray.

I hadn't thought of the top-to-bottom relay of nutrient solution. Hmmmm.

The only problem I foresee is "putting all my eggs into one basket". Having the two trays relying on the same reservoir, pumping system and flow puts an awful lot of dependence on the single system.

Any failure at that point would be catastrophic to the entire grow, but with proper monitoring and application, with a warning system in place, I could see it working efficiently.

Thanks for the suggestion!

 

[TexasMonster]

I (who admits I dont know squat about lights, yet) have been reading about the LEDs. I've noticed that they are more expensive than the HPS light system, but I hadnt thought about not needing the big fans, hoods, ducting, etc. It might be cost effective right off the bat if you look at it that way.

I cant wait to see your LED/HID test.

I've been reading everybodies grow journals.

 

[Rolling Thunder]

I just dont like some of the claims by these LED light manufacturers that a 90 watt LED light will perform as well as 400 watts of HID.

There is a world of difference between theory and reality, to be sure. They might be what the manufacturer claims, in a perfect world; but in reality, they are less than they claim; at least for now. I'm very encouraged by the future prospects of what LEDs will become in the next phase or wave of their development. - RT