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Grams-Per-Watt is an erroneous measure of productivity

S

StealthyStalks

I know the errors are more confusing then that. I never cared when people say their GPW
Since some strains require much more time to bloom to full quality and others just grow fast and produce weight.

I only use the grams per watt test on my personal grows to test if my techniques are improving or not. And that's they only thing you can really test with it. Comparing your buddies similar setup won't help much either, the conditions from one grow to another vary so much, its impossible.

Its mostly new growers that don't understand what they are testing, comparing themselves to other new growers. A pointless cycle really... But theres nothing you can do about, new growers log on everyday, too hard and too many to train on proper use of the method.



You are exactly right. If you are doing a comparison it needs to be compared to another method using the same pheno from the same strain; preferably clones from the same mother to be exact.
 

TickleMyBalls

just don't molest my colas..
Veteran
you still haven't convinced me. pay your bills and no one is looking at your power consumption. if you're growing any respectable amount of herb you're too busy to waste your time figuring all of this garbage out. no one is going to add up every KWH for any grow over 4 or 5kw. all big growers measure lbs. per 1kw of light and you're not gonna convince me any different. efficiency doesn't have anything to do with getting caught by LEO. Loose lips get people busted, not power consumption.

By the way, good luck putting 4200w in a 6x6 space, lol! what are you retarded? efficiency in growing is how well you use your space, not how little power you consume, that would be how power efficient your grow is. growers want to pump the most out of a given space, not a given amount of electricity. That is where YOU are offbase. the gram per watt isn't talking about the wattage of electricity, it is really meant to convey the intensity of the light. if you want to get technical, it should really be grams per Lumen.
 
S

StealthyStalks

you still haven't convinced me. pay your bills and no one is looking at your power consumption. if you're growing any respectable amount of herb you're too busy to waste your time figuring all of this garbage out. no one is going to add up every KWH for any grow over 4 or 5kw. all big growers measure lbs. per 1kw of light and you're not gonna convince me any different. efficiency doesn't have anything to do with getting caught by LEO. Loose lips get people busted, not power consumption.

By the way, good luck putting 4200w in a 6x6 space, lol! what are you retarded? efficiency in growing is how well you use your space, not how little power you consume, that would be how power efficient your grow is. growers want to pump the most out of a given space, not a given amount of electricity. That is where YOU are offbase. the gram per watt isn't talking about the wattage of electricity, it is really meant to convey the intensity of the light. if you want to get technical, it should really be grams per Lumen.


Dude, the whole point of the post was to point out the erroneous use of Grams-Per-Watt used on this site and not to take insults from someone I don't even know. You are arguing Grams-Per-Area which is a whole different matter; and you are calling me retarded??? You are getting warmer with your Grams-Per-Lumens though, but it is still as erroneous as Grams-Per-Watt; you would need to use Grams-Per-Megalumen Hours. But at least you were arguing energy efficiency there instead of area efficiency.

By the way, by using an air plenum to precondition the air and laminar air flow, it is totally possible to pack 4,200 watts into a 6x6 area if you wanted to deal with having to use CO2. I have a controls engineering background so I am far from retarded, Pal.

I know you are concerned about getting the most out of a grow space, so I would suggest you hang another 1k light in your 6x6 grow area because at 28 watts per square foot you have it way under powered. You should be pulling in at least 2.5lbs on the low end and 4lbs on the high end in a space like that!
 
umm GPW is a rule of thumb

It isn't some standard. You can include all the factors but then it's a study. There isn't too many factors so you could certainly do it but then we're talking about something different than a rule of thumb.

Nothing more, nothing less.
 
I was just trying to point out that the grams-per-watt measuring gauge everyone seems to use on here is erroneous. If one must use a gauge to measure efficiency then they need to use Grams-Per-Kilowatt Hour used.

I'm gonna take the unpopular stance here, just for the sake of argument.

g/kWh is a very good measure of overall productivity. g/W is a very good measure of overall efficiency.


Let me give an example...
In my situation, I'm limited by the electricity I'm comfortable using. 2000w of lighting, plus a heavy-duty pump, large A/C unit, fans, air pumps, etc. All that adds up.
That's the maximum electricity I'm willing to use. Not because of the bill, but because I don't want myself to stand out too much from my neighbors. My meter is already spinning its ass off.

So I want to maximize the bud I can get from 2 or 3 harvests before I shut it down at this location. I'm not going to be growing continuously for years because I'm scared shitless of these extremely harsh laws here.

So 2000w is what I'm using. I designed my system around those 2 lights. Time isn't nearly as much of a factor as it may be for some other growers who are set up in a permanent location and are trying to keep the buds coming.

I'm covering a 13x5 area with these two lights by growing vertically. That gives me more potential for each yield. Each yield should theoretically take the same amount of time, whether I cover that area with vertical light or put a dreaded hood on my lights and hang them horizontally.
So GPW becomes the number to look at. How much can I potentially yield in the time it takes for one harvest from x amount of space and y amount of lighting?

Also, g/kWh doesn't take into account that a fine sativa may take 14 weeks or longer to fully ripen. Let's say you're a master grower growing the finest sativa you've ever tasted, but it takes you 15 weeks to pull a beautiful 250g harvest under a 250w hps. You're stoked with the harvest.

Meanwhile, some 16 year old kid got his hands on a chronic seed, threw it under a 150 watt hps in a closet and left the door open for ventilation, used miracle grow or some crap, tap water w/ chlorine, the works... and got a 75 grams of half-decent bud, just because he was growing a super commercial crop. And he did it all in barely over 7 weeks.
All of a sudden the kid's g/kWh (and hence productivity) is higher than yours, the master grower.
But you got 1 g/W, and the kid got .5 g/W.
What's the deal there?
His productivity is much higher, but it's only due to strain choice. The master grower's grow was actually much more successful (not to say the kid wasn't happy lol) since he grew a refined sativa which he considered to be of higher value.

Does that make both measures irrelevant? They each have their place. It's pointless to trash talk GPW just because you'd rather measure something else.


Tthe bottom line is that GPW is the easiest (and quickest) way to calculate the potential of a grower's system.


And all that being said, productivity matters much more than efficiency in the long run, but these are just different measures to show different things.
 
who the fuck cares how any of you measure your productivity? Only total fucking assholes argue something as stupid as this. Do you grow enough weed for your purposes or not? That is the question. Of course we all want more production under less light/ area/ kwh/ whatever the fuck else you guys wanna argue about. g per w is a great way to measure. so is g per w per unit of time. ya'll need to settle down and remember this is about growing, not about how big your fucking cocks are compared to the next guy. Tune in your setup and be happy or not. :rant:
 

MeanBean

Member
Sure is embarrassing that someone brings a valid point to the table only to get battered by these useless stabs at the idea. You’re scaring all the smart people away dummy. Why bring your stupid 6x6 grow into this???

Has nothing to do with electricity use..

Flaming heat: u sound like a real tool. there's no reason to bash measuring results.
 
mean bean: i said specifically that either method of measurement was great. no method bashing here. i am bashing dumb fuckers that argue on the internet about dumb shit as though they have a stake in it. as if it fucking matters. if that makes me a tool, so be it. my point is that people should focus on whatever method they want and not try to impose/impress everybody else with their methods. this is for the spread of info, not for you to call names, like tool. a discussion of techniques is valid and helpful. an argument where people with anonymous names try to impress each other with real world credentials is just fucking stupid. hence the dick measuring example. "im an engineer, I'm a fucking bank executive, I worked for nasa, I etc.." WHO THE FUCK CARES. measure how you want, and be happy. your real occupation, or preference in measurement is arbitrary and unimportant. settle down and get a grip bro.
 

Okiedope

Active member
very good points made in this thread. i believe grams per watt and lbs per light are used because they are convenient and most stoners don't want to do the math. you are right to point out that this doesn't account for veg time and bloom period, not to mention power used on fans, pumps, air conditioners, dehumidifiers, etc. if you want a real benchmark you will account for the total power consumption of your grow over time.

hence the dick measuring example. "im an engineer, I'm a fucking bank executive, I worked for nasa, I etc.." WHO THE FUCK CARES.

... and you should trust me, I'm an engineer. :hide:
 
N

NicholasSmokes

I think grams per watt is an adequate measure. What gKwh really tell you above gw is that longer flowering strains cost more to grow. This is because in the vast majority of indoor gardens lights are using most of the electricity consumed.

For my own garden, I'd want to know the gw including all electricity used (not just lights), so I can get a clear idea of my productivity crop to crop. If you don't have a solid metric, it is much harder to make judgments about what techniques work and what don't.

However, the electrical usage beyond lights is going to vary by local conditions, so I think only light wattage should be used when comparing two different grows. For example: Imagine two identical grows except that one is using a new nutrient and also needs more cooling due to the outdoor climate. If you wanted to compare the effectiveness of the nutrient, you would skew the measurement by including the electricity usage of the cooling.

As a side note, all of the posters making ad hominem attacks are ruining ICG. If you can't discuss any idea civilly and explain clearly why you agree or disagree, why are you even on a discussion forum?
 

Okiedope

Active member
who the fuck cares how any of you measure your productivity? Only total fucking assholes argue something as stupid as this. Do you grow enough weed for your purposes or not? That is the question. Of course we all want more production under less light/ area/ kwh/ whatever the fuck else you guys wanna argue about. g per w is a great way to measure. so is g per w per unit of time. ya'll need to settle down and remember this is about growing, not about how big your fucking cocks are compared to the next guy. Tune in your setup and be happy or not. :rant:

let me see if i can help...

for a serious commercial grower who is trying to get the most out of their indoor setup setting up a true benchmark will be the first step of performance improvement. it is near impossible to improve when you don't know 'where you are now'. and for many setups a simple grams per watt figure will not be enough.

the op is correct in his claims regardless of what you think or how big of an asshole you think he is for wanting an efficient setup. efficiency and performance improvement have nothing to do with dick measuring contests, and everything to do with being a responsible human being -- making the most out of the limited resources you are given.

personally i admire anybody trying to be an efficient producer. as prices continue to correct on MMJ the efficient producer will be king and all of the Flamingheats of our community will find something else to do.

strive to make the most of what you have folks. it will ultimately mean higher margins for you and lower prices for your patients.
 
dude you misread the post and missed my point in its entirety. im saying that people should measure how they wanna measure and not get into arguments about it. i am not bashing any specific method, all are valid. the others calling people retarded, tool, etc are what i rally against. its to the point that you cant state an opinion on here w/o others calling you names and trying to put you down. NOT COOL NOT CONSTRUCTIVE. Nobody is an asshole for wanting more efficiency. people are assholes for arguing about it instead of having a civil discussion. case in point, 2/3's of the peeps in this thread.
 
S

StealthyStalks

very good points made in this thread. i believe grams per watt and lbs per light are used because they are convenient and most stoners don't want to do the math. you are right to point out that this doesn't account for veg time and bloom period, not to mention power used on fans, pumps, air conditioners, dehumidifiers, etc. if you want a real benchmark you will account for the total power consumption of your grow over time.



... and you should trust me, I'm an engineer. :hide:



Okiedope, my original post was for simplicity reason only. If you read through my comments you'll see I agree one would need to take into account all the energy inputs: fans, pumps, lighting, air conditioners, dehumidifiers, etc. as well as prorated energy use for the mothers. Also it is important that any comparisons be strain/pheno specific and the use of clones would give the best measure of efficiency comparison.

I knew an engineer would get it!
 
D

dongle69

That's all fine and dandy if you are someone like dongle69 who grows where it is quasi-legal and power consumption efficiencies really don't matter much.
Efficiency always matters, no matter where you are growing.
I will give gpw sometimes if someone asks, but my own measure of productivity includes profit per year, without sacrificing quality.
Christ, anyone can have a state-of-the-art 50,000 watt system set up under those conditions!
Good luck with that.
I have seen "anyone" fail many times.
I have also been doing this long before I had my current "conditions."
 
Last edited:
S

StealthyStalks

I'm gonna take the unpopular stance here, just for the sake of argument.

g/kWh is a very good measure of overall productivity. g/W is a very good measure of overall efficiency.


Let me give an example...
In my situation, I'm limited by the electricity I'm comfortable using. 2000w of lighting, plus a heavy-duty pump, large A/C unit, fans, air pumps, etc. All that adds up.
That's the maximum electricity I'm willing to use. Not because of the bill, but because I don't want myself to stand out too much from my neighbors. My meter is already spinning its ass off.

So I want to maximize the bud I can get from 2 or 3 harvests before I shut it down at this location. I'm not going to be growing continuously for years because I'm scared shitless of these extremely harsh laws here.

So 2000w is what I'm using. I designed my system around those 2 lights. Time isn't nearly as much of a factor as it may be for some other growers who are set up in a permanent location and are trying to keep the buds coming.

I'm covering a 13x5 area with these two lights by growing vertically. That gives me more potential for each yield. Each yield should theoretically take the same amount of time, whether I cover that area with vertical light or put a dreaded hood on my lights and hang them horizontally.
So GPW becomes the number to look at. How much can I potentially yield in the time it takes for one harvest from x amount of space and y amount of lighting?

Also, g/kWh doesn't take into account that a fine sativa may take 14 weeks or longer to fully ripen. Let's say you're a master grower growing the finest sativa you've ever tasted, but it takes you 15 weeks to pull a beautiful 250g harvest under a 250w hps. You're stoked with the harvest.

Meanwhile, some 16 year old kid got his hands on a chronic seed, threw it under a 150 watt hps in a closet and left the door open for ventilation, used miracle grow or some crap, tap water w/ chlorine, the works... and got a 75 grams of half-decent bud, just because he was growing a super commercial crop. And he did it all in barely over 7 weeks.
All of a sudden the kid's g/kWh (and hence productivity) is higher than yours, the master grower.
But you got 1 g/W, and the kid got .5 g/W.
What's the deal there?
His productivity is much higher, but it's only due to strain choice. The master grower's grow was actually much more successful (not to say the kid wasn't happy lol) since he grew a refined sativa which he considered to be of higher value.

Does that make both measures irrelevant? They each have their place. It's pointless to trash talk GPW just because you'd rather measure something else.


Tthe bottom line is that GPW is the easiest (and quickest) way to calculate the potential of a grower's system.


And all that being said, productivity matters much more than efficiency in the long run, but these are just different measures to show different things.


I agree with most of what you said here. The original post was for the sake of simplicity; to get the point across. If you read through my comments you will see I advocate comparing the same strain/pheno or clones for an accurate comparison of any production method.

Thanks for being respectful. Get this man a bud! :smokeit:
 
B

Bazarocka

Thats

Thats

Just made 2230 Grams on 1800 Watts (3 x 600W)
Vegged 5½ week
Bloom 8 Weeks :smokeit:

about right. I pull about 2016 to 2200 grams per harvest with/1600 watts. Thats in a Aero system. But I never veg~~~clones go straight into bloom and 45 to 60 days later. :smokeit:
 

foomar

Luddite
ICMag Donor
Veteran
With electricity prices already high here and set to double within a few years , increasing efficiency and reduceing waste is fast becomeing a religion.

Grammes per watt says something general ,

Grammes per Kwh says more about the local climate in many cases and could be skewed by AC or dehumidifiers essential to that location ,

With a long running permanent floweroom the only usefull figure i could come up with is an overall Grammes per Kwh consumed per year.

0.57 grammes per Kwh consumed

Cost per gramme of bud £0.207 or about five pounds per ounce.

Only of personal interest but has gone up steadily over the years with better techniques and higher yielding genetics despite adding males and seed plants to the mix , and i like to put numbers on things
 
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