2018 Light Efficiency Ultimate Battle

[aerorev]

First post in the forum. I’ve been growing for about 16 years mainly outdoor.

Started indoor a couple years ago using 1000w’s HPS’s with magnetic ballasts. Later on I switched to 400w Phillips HPS with Lumatek electronic ballasts for efficiency.

I’m seeing a lot of discussion and contradictory information on the efficiency of LEDs vs HPS vs CMH and I’m trying to clear the waters. If I’m making the full switch and investing a couple thousand I might be sure of what’s working better. I’ve seen side by side grows on forums and either some are poorly done without any kind of scientific method approach or they are biased. The cannabis industry is looking more and more like the fitness supplement industry with a lot of big brands marketing things with incorrect data.

In your opinion what is the most efficient light source when comparing gram per watt of dried weight? (Power consumption vs grams of dried weight)

Other factors and advantages such as heat emission, potency, cost of the equipment, etc are not to be compared. If some lights have better spectrum, etc is also not important. We will focus on gram per watt exclusively on this discussion and keep it focused around this subject.

Let me know about your personal opinion, links to properly done side by sides, etc…

 

[Hands On]

[QUOTE

The cannabis industry is looking more and more like the fitness supplement industry with a lot of big brands marketing things with incorrect data.

[/QUOTE]

 

[Hands On]

That is a true statement

 

[aerorev]

no one has some input?

 

[heisen]

The ol tired gpw debate
If I veg under 1000w hps for 2 months,
You veg for 2 weeks and I pull 3 times what you pull does that mean your GPW is less?
Gpw is the dumbest shit people come up with as if its some actual real measurment.

You can do a side by side in your own grow room with 2 identical lights,veg 1 an extra month and your "gpw" will go up significantly.so where do u draw the line

 

[Dan789]

The ol tired gpw debate
If I veg under 1000w hps for 2 months,
You veg for 2 weeks and I pull 3 times what you pull does that mean your GPW is less?
Gpw is the dumbest shit people come up with as if its some actual real measurment.

You can do a side by side in your own grow room with 2 identical lights,veg 1 an extra month and your "gpw" will go up significantly.so where do u draw the line

To say nothing of grower knowledge, nutrients, soil/growing mediums and most importantly genetics of the particular strains.
That said, I’m in the cob corner with my 12 vero 29 Rapid led fixture kit. Plants did better than those under just regular LEDs (older lighthouse black stars). Wattage to wattage, actual draw measured at the wall.

 

[RooR5mm]

Micromoles

 

[xavier7995]

From what i gather led is the most efficient in terms of energy use, followed by the cmh, then hps way down there. It is sort of the inverse in terms of setup costs. Not sure if there is really that big of a difference between the led and cmh fixtures in terms of efficiency.

Led really has come a long way and is what i would be looking at if you are doing a homegrow, they are better suited to the ceiling heights we are working with.

 

[aerorev]

The ol tired gpw debate
If I veg under 1000w hps for 2 months,
You veg for 2 weeks and I pull 3 times what you pull does that mean your GPW is less?
Gpw is the dumbest shit people come up with as if its some actual real measurment.

You can do a side by side in your own grow room with 2 identical lights,veg 1 an extra month and your "gpw" will go up significantly.so where do u draw the line

I'm assuming same everything. You can do side by side and get gram per watt measurement.

Let me know what you think on this simplified setup:

grow space: 80cm x 80cm with co2 supplementation
grow medium: HPA using DTW
SOG with a indica strain like Afghani #1 for example

If you set 2 rooms exactly the same with ofc controlled atmosphere and same clone would you get more out of a 400w HPS or 400w LED?

I know this is not scientific because I would have to state LED model and the way they were running, type of HPS/ reflectors, etc...

Who would win and yield more in the end?

 

[aerorev]

From what i gather led is the most efficient in terms of energy use, followed by the cmh, then hps way down there. It is sort of the inverse in terms of setup costs. Not sure if there is really that big of a difference between the led and cmh fixtures in terms of efficiency.

Led really has come a long way and is what i would be looking at if you are doing a homegrow, they are better suited to the ceiling heights we are working with.

I'm more and more inclined to think this was...