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LED grams per watt

lenngray

New Member
After writing my post "LED lumens, again", I realized
that "how much", regarding "I get so much yeild" was,
itself, a useful statistic.

Under HPS, people used to talk about the achievable
goal of 1 gram (dried) per watt per grow season. I
never got much more than about a half gram per watt.

But now, with these claims of 1/3 the power of HPS
for their LED lights, someone should be achieving
3 grams per watt per season.

Let's hear your numbers, guys. This should be beyond
hype, and relates to money.

Anyone?
 

JJ Bones

Nug of the Month: Feb 2013
I got .77 GPW on one grow. Trying 1000W of LED now, so we'll see what the GPW is there. True 1000W consumption.
 

HipsterDoofus

On Vacation
How does one add up the watts? What's the standard? LED's are sold at rated capacity but often draw only about half of that. So which number is used?

What about all the fans, pumps and other electrical draws that HID's require but LED's might not? Isnt' it only fair to add those in on the HID side? How do you get to number of watts?
 

JJ Bones

Nug of the Month: Feb 2013
I'm talking consumption, how much electricity is truly being used, not all the LED mumbo jumbo.

For HID and LED one would add fans etc to it. However you can also look at it from just the light point of view and how much light produced what. Of course we all know light is not the grow all be all, just different metrics to take note of.
 

lenngray

New Member
Actual draw of the LIGHT at the wall is what intuitively counts. Running a 3 watt LED at 2 watts uses 2 watts.
The current-supply may lose a percent or 3, but as we say, that's down "in the noise". I can't imagine that
any pumps you're using for the LEDs are beyond the noise level, and I doubt that HPS people were counting
any hydro pumps. They probably also weren't counting heat-removal fans, but if they were ignoring actual
air-conditioning equipment, I would have considered that cheating. So just the basic data would be good.
 

s1ingblade

New Member
I will definitely keep you all posted on my next led grow. I wasn't going to mess with them anymore but after all the led info and finished grow journals here I am thinking and hoping I was doing something else wrong. I would have to say my last harvest was real close to .25 GPW.
 

lenngray

New Member
I'm not sure if I'm missing something, (I just started following up details of what people tell me), but on SteveHman's 780W LED grow, he wrote, on changing from 600W to 780W, "My goal for this grow is to net a lb out of it. I netted 3/4 out of a 2x4 space, so upping the watts by 180 and adding 2x2 more in space (a 50% increase in space). I think a 30% increase in yield is reasonable."

So, with a reasonable hydro setup, with LEDs, he was (17 months ago) only looking at 454 grams for 780 watts of LEDs. Is this the level of "improvement" we're supposed to settle for with LEDs? As I said, people have written about 1 gram/watt for quite some time with HPS.
 

lenngray

New Member
I'd love to hear about anyone's results in taking advantage of LEDs' minimal heat generation to use low-tech CO2 to increase yield without losing the CO2 to the venting of heat.
 

lenngray

New Member
So, apparently hosebomber, in another thread, gave some definitive
data about this, debunking the 1/3 the power, and thus the 3 grams
per watt. So, the yield we'd be looking for for commercial lights is
1.5 grams per watt.

Is anyone getting that? With whose lights? Note that it's only
with a GOOD light that you'll even get that. LEDs are barely ready
for prime time -- "truth about LEDS" notwithstanding.


- Lenny Gray -


| On 8-18-12, at 10:44 AM,
| Hosebomber wrote:
|
| Re: LED lumens, again
|
| To date no other company has shown the proven results as well
| as Advance IMHO. However there are a few good companies on the
| market. If you see a company claiming 1/3rd the power use of
| a HPS or claiming the light is a 900 and actually draws 387
| (true statement about 1 company) close that browser tab and
| move on to the next. If they are lying about their product
| there is a reason.
|
| IT IS NOT POSSIBLE WITH CURRENT MASS PRODUCED
| MODELS TO GET THE SAME RESULTS AS AN HPS WITH
| ANYTHING LESS THAN 2/3RD THE POWER.
| [emphasis Lenny's]
|
| ie with a very good 400 watt led you could get about the
| same yield as a 600 watt HPS. To get better efficiency than
| that it needs to be a custom panel built for your grow area
| and then 40% power reduction is close to max. I've gotten as
| high as 47% power reduction with almost exactly the same yield
| (within 1 gram of tomatoes) in a hydro setup with light barriers
| and running the same nuits to both sides and light being the
| only variable.
 

Buckshot

Member of the Month: Nov 2013 - Nug of the Month: Mar 2013, Dec 2014 - Plant of the Month: Mar 2018
I'd love to hear about anyone's results in taking advantage of LEDs' minimal heat generation to use low-tech CO2 to increase yield without losing the CO2 to the venting of heat.
It seems like you just want a fight. What is your point with all these posts? I think what you should be looking at is cost per gram spread over a 5 year period.

PS I do use a "low-tech" CO2 generator but how to quantify its results against a ducted system is beyond me

PSS I have never kept track of weight in that way, I just make sure I do not exceed my allowed weight at any given time. I would love to have the room and be allowed to show what LED can really do...
 

lenngray

New Member
Actually, I'm more than a little averse to fraud.

I'd be all in favor of taking the cost per gram over 5 years, but if we just wait without being willing to look until then, it amounts to condoning 5 years worth of fraud.

When NOBODY is reporting 2-3 grams per watt with LEDs, it's not unreasonable to ask if LEDs aren't only a nice-pretty-colors fraud.

I think of the yeast/sugar CO2 as a cheap nute that just doesn't help with a leaky ducted system, and consider it part of the LED grams/watt benefit.
 

lenngray

New Member
So, Buckshot, you do understand that the thread "The Truth about LED lights" started, a year ago, with a post by a seller that included the line: "If you get about 300-400watts of LED lighting, you can replace a 1000watt HPS or MH system." Yes, and to the extent that that's true, if I get an old 19" picture-tube TV, I can also replace a 62" flat-screen TV. The implication of the "replace" was that it be the equivalent. Lying by implication.
 

Buckshot

Member of the Month: Nov 2013 - Nug of the Month: Mar 2013, Dec 2014 - Plant of the Month: Mar 2018
Actually, I'm more than a little averse to fraud.

I'd be all in favor of taking the cost per gram over 5 years, but if we just wait without being willing to look until then, it amounts to condoning 5 years worth of fraud.

When NOBODY is reporting 2-3 grams per watt with LEDs, it's not unreasonable to ask if LEDs aren't only a nice-pretty-colors fraud.

I think of the yeast/sugar CO2 as a cheap nute that just doesn't help with a leaky ducted system, and consider it part of the LED grams/watt benefit.
You can estimate a 5 year cost ... I thought you were an engineer
 

Buckshot

Member of the Month: Nov 2013 - Nug of the Month: Mar 2013, Dec 2014 - Plant of the Month: Mar 2018
So, Buckshot, you do understand that the thread "The Truth about LED lights" started, a year ago, with a post by a seller that included the line: "If you get about 300-400watts of LED lighting, you can replace a 1000watt HPS or MH system." Yes, and to the extent that that's true, if I get an old 19" picture-tube TV, I can also replace a 62" flat-screen TV. The implication of the "replace" was that it be the equivalent. Lying by implication.

Yes I do ... and there are slipery slopes everywhere. For example I alluded to space earlier... a 1000 watt hps light and a 400 watt LED placed in a 4 x 4 grow area "could" yield about the same but given more space the 1000 watt would prevail.
 

lenngray

New Member
You're alluding to the replacement costs of an HPS bulb?
Even if I decided to replace the bulb every 6 months as some have implied was necessary, I just looked up a replacement for my 55,000 lumen 400W as $20.88 shipped, so you're talking about the 9 x that, to be added to the cost? What's the cost of fraud. And which manufacturers' lights are going to match the yield of the HPS? And who's gonna guarantee that we got the right one, if everybody is willing to testify to the lies?
 

Buckshot

Member of the Month: Nov 2013 - Nug of the Month: Mar 2013, Dec 2014 - Plant of the Month: Mar 2018
You're alluding to the replacement costs of an HPS bulb?
Even if I decided to replace the bulb every 6 months as some have implied was necessary, I just looked up a replacement for my 55,000 lumen 400W as $20.88 shipped, so you're talking about the 9 x that, to be added to the cost? What's the cost of fraud. And which manufacturers' lights are going to match the yield of the HPS? And who's gonna guarantee that we got the right one, if everybody is willing to testify to the lies?
initial cost of lights and fixtures
bulbs
cost of electricity
aditional cost of ducts and fans plus the electricity
Almost double water for HPS

then figure yeild into it
 

Buckshot

Member of the Month: Nov 2013 - Nug of the Month: Mar 2013, Dec 2014 - Plant of the Month: Mar 2018
You're alluding to the replacement costs of an HPS bulb?
Even if I decided to replace the bulb every 6 months as some have implied was necessary, I just looked up a replacement for my 55,000 lumen 400W as $20.88 shipped, so you're talking about the 9 x that, to be added to the cost? What's the cost of fraud. And which manufacturers' lights are going to match the yield of the HPS? And who's gonna guarantee that we got the right one, if everybody is willing to testify to the lies?
I thought we were talking about 1000 watt bulbs ... try $70.00-100.00 x 9 I just looked up a nice Hortilux HX66785 1000-Watt Super HPS Spectrum Grow Bulb and found it at a mere 72 bucks :3:
 

Budmaster LED

420 Sponsor
Well everyone is obsessed with GPW as they are with Lumens.

We beat the 1 GPW all the time but this is not a fair measureing system to use with all the varied lighting systems around at the moment.

We feel this should shift more to GPSQM - GPW, meaning Grammes per Square Meter or Grammes Per Week.

This also makes for a fairer representation of yield for different strains that have different growth periods to be measured.
 

LEDBud

Well-Known Member
I am pretty sure the only way one could acquire 2G a watt from LED's would be if they use a light mover bar and did a fast double harvest / harvest the top buds lower the lights and mature the bottom scrag.
I have Just bought my first LED lights and am currently starting a 5 plant grow in a 2x4x6 plywood grow box. pics to come at some point after the cute seedling stage.
 

Icemud

Member of the Month: July 2012, July 2014 - Nug of the Month: July 2012
Back to the main question of what HID and LED growers are getting in yield... Here are my results from all my grows.

The grows were all in the exact same growtent (a 2x4 hydrohut silver that measures 2.5'x5'x7'). Each grow featured 6 plants of various strains so a direct comparison is not really accurate, but more of a "trend" is visible with HID vs LED. Between each grow the soil has had minor changes as well as nutrients so again, this can not be used as a "scientific" comparison, however I do notice a trend of a equal or higher Gram/watt with LED vs HID...however yields are slightly lower under LED vs HID... if given equal draw wattage I think LED would have the edge...

Here are my results.

Grow 1: 1000w HID (400w CMH + 600w HPS) Total yield 574g or .57 grams/watt
Grow 2: 1000w HID (400w CMH + 600w HPS) Total yield 547g or .55 grams/watt
Grow 3: 1000w HID (400w CMH + 600w HPS) No Yield Data (Powder Mildew took over)
Grow 4: 1000w HID (400w CMH + 600w HPS) Total yield 325g or .33 grams/watt
Grow 5: 580w (400w CMH + Mars II 400w) Total yield 245g or .42 grams/watt
Grow 6: 540w HID (3x Mars II 400w models) Total yield 308g or .57 grams/watt
Grow 7: Under 300w (2x Intelligent Gro, GEN1, 180w each on dimmer) Total yield 191g or .63 grams/watt
Grow 8: 3x Intelligent Gro, GEN2, 180w draw each, Total yield 367g or .70 grams/watt

Now like I mentioned, even though grown under similar conditions, there were too many variables that changed between grows to confirm this more than just a reference set of data.
 
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