2018 light efficiency ultimate battle

In your opinion what is the most efficient light source when comparing gram per watt of dried weight

  • HPS (specify which one on the thread)

  • LED (specify which one on the thread, diy, etc)

  • CMH / LEC (specify which one on the thread)

  • Metal Halide (specify which one on the thread)

  • CFL


Results are only viewable after voting.

aerorev

Member
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…
 

hotrodharley

Well-Known Member
The CMH units. If properly used. However cooling can be an issue like with LED.

Personally I use HPS in an air cooled reflector. Put the plants right up under it using reasonable judgement.
 

brewbeer

Well-Known Member
Grams per watt metrics are misleading because the length of the veg cycle is not considered. For example, one would expect a higher yield from a CMH grow that vegged for 6 weeks, vs. 2 weeks before flip.

IMO, a more accurate metric to use is grams per kilowatt-hours, and to include electric consumption from other major electricity consumers, like AC and vent fans.
 

aerorev

Member
Grams per watt metrics are misleading because the length of the veg cycle is not considered. For example, one would expect a higher yield from a CMH grow that vegged for 6 weeks, vs. 2 weeks before flip.

IMO, a more accurate metric to use is grams per kilowatt-hours, and to include electric consumption from other major electricity consumers, like AC and vent fans.
This is true but consider some people don't even go through Veg time.

That is an accurate metric but I'm focusing only on light efficiency for now.
 

coreywebster

Well-Known Member
cooling can be an issue with LED? :?
He means you cant just buy an air cooled hood like with a bulb. You can adapt or use a hood to build a LED though.
There are also a lot of people who get into LED, specifically blurpls because they have the misguided opinion they don't create heat.
What colour temp do you recommend for LED?
3500k for a light used for both veg and flower.
 

brewbeer

Well-Known Member
This is true but consider some people don't even go through Veg time.

That is an accurate metric but I'm focusing only on light efficiency for now.
The metric is still comparable even with no veg time.

Light efficiency shouldn’t be taken in a vacuum. Some super efficient LED grows might need supplemental heat in the winter, where an HID grow may not. The reverse applies to air conditioning in the summer, where it may be needed in an HID grow, but maybe not an LED grow. If the light you are using require additional energy input, that should be factored in.
 

patrickkawi37

Well-Known Member
Efficiency ???? Dude are hitting 3.5 pounds + from a thousand watt hps fixture from a 5x5 footprint and the fixture cost less than 400 bucks . How does it get more efficient than that? 1.3-1.5 gpw average for me with 1000watt hps. Leds are a waste of money and time. People say ohh well you ac don't have to work as hard. Lemme enlighten people on this. If you have a full canopy.. and your Acs aren't working wide open, then you're not pulling enough water out of the air and the dehumidifiers turn on. Giving up power on one end have to use it on the other.. for what? To save a few hundred bucks a month on power? All that matters is what fixture hits the most weight. If you have a 12 lighter, and use decide to go LED, now the room you used to pull 33+ packs out of now just hit ... 27 let's say for random number knowing it would probably be Less. Those 6 packs.. were basically your run cost lols. Someone who grows with leds explain to me how that's cost effective .
With all that being said if you grow in a closet or a tiny area for a hobby then the situation might be different for you. But people trying to turn an burn batches, dont waste your time switching from hps .
 

pulpoinspace

Well-Known Member
Efficiency ???? Dude are hitting 3.5 pounds + from a thousand watt hps fixture from a 5x5 footprint and the fixture cost less than 400 bucks .
Efficiency is how many watts are wasted as heat compared to how many watts are produced as photons available to the plant. it has nothing to do with costs of the fixture.

So what you're saying is you get 1.5 gpw with HPS system? thats pretty good.

IMO gpw is a horrible measure of lamp efficiency.
 
Last edited:

aerorev

Member
The metric is still comparable even with no veg time.

Light efficiency shouldn’t be taken in a vacuum. Some super efficient LED grows might need supplemental heat in the winter, where an HID grow may not. The reverse applies to air conditioning in the summer, where it may be needed in an HID grow, but maybe not an LED grow. If the light you are using require additional energy input, that should be factored in.
I'm only trying to compare the light efficiency not the full grow efficiency. ;)
 

aerorev

Member
Efficiency is how many watts are wasted as heat compared to how many watts are produced as photons available to the plant. it has nothing to do with costs of the fixture.

So what you're saying is you get 1.5 gpw with HPS system? thats pretty good.

IMO gpw is still a pretty horrible measure of lamp efficiency.
That's it, for this comparison it doesn't matter if you spend 500 or 5000 on your growroom, cost is not taken in consideration.

I believe LED's are indeed more efficient since you get more lumens for the sam amount of watt's.
 

patrickkawi37

Well-Known Member
Efficiency is how many watts are wasted as heat compared to how many watts are produced as photons available to the plant. it has nothing to do with costs of the fixture.

So what you're saying is you get 1.5 gpw with HPS system? thats pretty good.

IMO gpw is a horrible measure of lamp efficiency.
How is else is an effective way of measuring it?. My cost to grow a pound is around 700 bucks. Which some people say is high. But if I'm pulling twice the weight out of the same size room as the dude next to me then who's got more food on the table at he end. That 700 includes employees and trimmers as well
 

1212ham

Well-Known Member
A couple observations.... He didn't test the more efficient of the Quantum Boards, LED strip lights, or good COB lights like Timber, with Citizen, Luminus, or Vero COBs. It's also interesting to note the he lists the SPYDRx at 2.17μmoles/j , while Fluence says 2.5.
 

pulpoinspace

Well-Known Member
How is else is an effective way of measuring it?. My cost to grow a pound is around 700 bucks. Which some people say is high. But if I'm pulling twice the weight out of the same size room as the dude next to me then who's got more food on the table at he end. That 700 includes employees and trimmers as well
in my opinion, gram per watt depends on additional factors. cost to grow and efficiency of lights is two different measures. one is measuring your whole operation and one is a simple fact about a light source. imo better way to measure light efficiency is ppfd or simpler ways like lumens per watt.

A couple observations.... He didn't test the more efficient of the Quantum Boards, LED strip lights, or good COB lights like Timber, with Citizen, Luminus, or Vero COBs. It's also interesting to note the he lists the SPYDRx at 2.17μmoles/j , while Fluence says 2.5.
I really wish he had tested those too. especially the veros as they are what i use. seems no one doubts the qbs most good cobs might perform similarly. hopefully he tests more.
 

patrickkawi37

Well-Known Member
in my opinion, gram per watt depends on additional factors. cost to grow and efficiency of lights is two different measures. one is measuring your whole operation and one is a simple fact about a light source. imo better way to measure light efficiency is ppfd or simpler ways like lumens per watt.



I really wish he had tested those too. especially the veros as they are what i use. seems no one doubts the qbs most good cobs might perform similarly. hopefully he tests more.

Why would you test lumens per watt.. lumens don't necessarily dictate the amount of weed you're getting at the end of the day and really that's what's matters . I've seen leds that put out badass reads on a par meter and people still suck with them. The proof has always been in the pudding . You don't see the jungle boys using no leds. Some plants don't want more light. I've hit my best weight under single ended thousand watt fixtures. All my flowering rooms are now DE. If I can't get back on the weight I was hitting with single ended soon,, should I keep them in because they have a better lumen output? No sir. I'm going to use what gets the most weed for the investment
 
Top