redi jedi
Well-Known Member
It matters if your a large scale producer...where you need to know your actual cost to produce. To stay competitive in the market...blah blah blah. But for the home grower, its just bragging rights
GPW (Grams Per Watt) standing calculation method
- Thread starter BM9AGS
- Start date
BM9AGS
Well-Known Member
Clearly!
I'm looking for a general system that's easy enough for a stoner to do with his fingers and toes. Thus: light watts an hour + room watts an hour divided by grams
Simple.
BM9AGS
Well-Known Member
It also matters to the home grower as generally home growers start growing because they don't want to pay for it. If paying for it didn't matter then yes it's purely hobby like with me. Which gives excellent bragging rights and epeen points
BM9AGS
Well-Known Member
@captainmorgan @SupraSPL
I'd like you guys to see this thread and inform me what system you're using.
Thank you!
I'd like you guys to see this thread and inform me what system you're using.
Thank you!
Budley Doright
Well-Known Member
How would that help pick a light? It has no bearing on anything because there is just way to many variables, you could not draw any conclusions other than you get more or less than whoever your comparing. Its only useful as I said, for personal costing IMO.
Budley Doright
Well-Known Member
I just said that lol.
BM9AGS
Well-Known Member
No not as I see it.
For the average legal grower they want to save a buck and grow their own. So if they look at HID the light and airflow needed are an easy 80$ a month here in Colorado.
If they're looking at led their bill is maybe $20 a month.
This would be good information to someone who haven't spent months or so looking for the best options as they can read that shitty LEDs produce .4 GPW and good LEDs produce 1.4 GPW and HID with the extra cooling needed are .75 GPW
Does it make sense to you? I'm interested in everyone's opinion.
I believe this to be important information for myself. The average home grower keeping with in the limits of the laws.
Budley Doright
Well-Known Member
I guess lol. Bud envy huh lol.
Budley Doright
Well-Known Member
Dont get me wrong I do see your point and its a noble cause, I have always thought the basic gram per watt was a bunch of hewey lol. The measuring would be complexed or easy depending on the setup. Mine would be easy as it's one circuit feeding the room. Again I doubt it will take off as a universal method but have at' ter
redi jedi
Well-Known Member
captainmorgan
Well-Known Member
GPW is not ideal for comparing your grow to someone else's but it's nice for measuring your own improvement against your previous grows or comparing strains in your garden..There are many factors like light source,environment,grow style and strain to name a few. Most HID guys just divide their weight by the bulb size so I do weight divided by my COB draw and don't include drivers or fans.
Kingrow1
Well-Known Member
Short veg times with lots of plants done in sea of green or perpetual 600watt air cooled hps 1.2m x 1.2m tent 6" inline fan. 4 weeks veg, 2 weeks pre flower, 8 weeks flowering should give you a good 5 crops a year with a small t5 veg tent.
If you hit 0.5g/watt your getting 300grams per crop x 5 crops a year = 1500g a year. Thats a lot for any homegrower and if you hit 1.0g/watt your looking at 3000g a year.
I cant think of anything more optimun fot the average home grower and most seem to end up in coco for ease and yeild.
That is how i use grams per watt and there is little confusion for me on the subject.
If you hit 0.5g/watt your getting 300grams per crop x 5 crops a year = 1500g a year. Thats a lot for any homegrower and if you hit 1.0g/watt your looking at 3000g a year.
I cant think of anything more optimun fot the average home grower and most seem to end up in coco for ease and yeild.
That is how i use grams per watt and there is little confusion for me on the subject.
racerboy71
bud bootlegger
didn't finish the thread, so excuse me if someone already said this..
the biggest problem with gpw is that it doesn't take time into the equation.. meaning, say someone spent 30 days vegging a plant.. totally making numbers up here btw.. 30 day veg, 600 watt hps, and yielded 600 grams to make things nice and easy.. that'd equal 1 gpw..
now, take person number 2.. person 2 also used a 600 watt hps bulb, but they vegged their plants for say, 60 days rather than person one's 30, but they also yielded 600 grams, which would also make them 1 gpw, but yet they took twice as long to veg their plants as person one, yet they yielded the same weight.. they could both say they achieved 1 gpw, but in reality who had the better grow? i'd say the person who used less electricity over all to yield the same results..
BM9AGS
Well-Known Member
Excellent point!
Aeroknow
Well-Known Member
When I first read the words GPW on overgrow I think, I could sware it was supposed to include veg watts also.
I was still rocking my homemade tubes/rails similar to the now aeroflo. Zero veg, we put rooted cuts directly into flower. Very effecient. I haven't grown that way for quite awhile. I get some serious veg on nowadays, but i don't need to have an aneurysm trying to compute veg watts into some kind of formulation. My bloom rooms are always on 12/12, and when I build a setup, a certain amount of veg watts and space are going to be needed to continually fill the bloom rooms.
I was still rocking my homemade tubes/rails similar to the now aeroflo. Zero veg, we put rooted cuts directly into flower. Very effecient. I haven't grown that way for quite awhile. I get some serious veg on nowadays, but i don't need to have an aneurysm trying to compute veg watts into some kind of formulation. My bloom rooms are always on 12/12, and when I build a setup, a certain amount of veg watts and space are going to be needed to continually fill the bloom rooms.
SupraSPL
Well-Known Member
Same as Cap, I go by gr/dissipation W (subtract fan and driver losses) because for a long time we would go by HID bulb dissipation. It make sense when we are trying to understand the basic capabilities of a particular light source because it removes some of the variables.
I agree, time needs to be taken into account. Growers that run higher canopy temps may get a gpw boost but also need more time to come to real completion (all red/brown hairs for most varieties). So you could adjust it to gpw/60 days of flowering or something along those lines.
To take it a step further you can look at system gpw, very important number to focus on for your grow. It does introduce more variables especially climate/season, so maybe less useful to compare from one grower to another.
System efficiency can be significantly improved by reducing waste heat while getting the same job done, which is possible using high efficiency LED. The difference can be as much as 3X less heat versus the very best HPS in brand new condition.
I agree, time needs to be taken into account. Growers that run higher canopy temps may get a gpw boost but also need more time to come to real completion (all red/brown hairs for most varieties). So you could adjust it to gpw/60 days of flowering or something along those lines.
To take it a step further you can look at system gpw, very important number to focus on for your grow. It does introduce more variables especially climate/season, so maybe less useful to compare from one grower to another.
System efficiency can be significantly improved by reducing waste heat while getting the same job done, which is possible using high efficiency LED. The difference can be as much as 3X less heat versus the very best HPS in brand new condition.
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SupraSPL
Well-Known Member
Regarding veg time and wattage, it is great to optimize that for your own grow and analyze your total system efficiency. But it should be kep separate from gpw comparing flowering lights.
For example some growers might veg outdoors/balcony etc and flower indoors. Some growers might use ultra high efficiency veg lights and others might use fluoro. But in the end the important thing is that it is vegged to the proper size for the pot and space it is in. You can do it fast or slow, efficiently or inefficiently, but it is a separate issue from gpw when comparing flowering lamps.
For example some growers might veg outdoors/balcony etc and flower indoors. Some growers might use ultra high efficiency veg lights and others might use fluoro. But in the end the important thing is that it is vegged to the proper size for the pot and space it is in. You can do it fast or slow, efficiently or inefficiently, but it is a separate issue from gpw when comparing flowering lamps.
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Kingrow1
Well-Known Member
Power consumption per gram would be a far more accurate way to deal with all the different sysyems, watteges and styles of grow.
A watt is quite a redundant measure for commercial growers, im guessing their more electrical bill per gram than watts and hence where leds make wild claims on magically giving you more watts for the same amount of electricity.
A watt is quite a redundant measure for commercial growers, im guessing their more electrical bill per gram than watts and hence where leds make wild claims on magically giving you more watts for the same amount of electricity.
BM9AGS
Well-Known Member
Yes there's many ways about this.
I couldn't find one single system! as long as we're all on the same page with grams divided by watts it'll still work
I'd like to compile these GPW results in a list. It would answer questions that are commonly asked and also we can see quantifiable real results in house (RIU)
Yes there are still variables like unhealthy plants and liars and wet product and of course strain and veg times and so on.
But I have a need for data and think it would be benifitial for the community to see data compiled on lights showing that average of this light is getting this GPW and that light getting that.