Lighting Grams per watt calculations ?

Frenjamin Banklin

Hello is this thing on
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So good day AFN, have a serious question as a grower on my fourth go round.
I run DWC buckets, 6 at a time. Been running DP and FB seeds and having consistent 5-6 oz of good bud per plant. So 30 per room/run.

I run custom 3k/4K cob rails four to a rail so each plant splits a pair. I run max in final weeks of flower at 100w per plant at 18” so 600 watts in the room in final flower. So I figure about 1.45 gram/w based on 600w.

But here is my question about gram per watt.
I run those rails on dimmers and a kill a watt so I know the exact wattage I’m pulling.
In the first week I run them 12” at 25w per plant.
Week 2-5 I run them about 50w per plant at 18”
Week five on I start pushing 10 per week till I hit the 100/plant.
And I run 90-100 days due to the 8 gallon buckets and MC.

So should I be doing some crazy formulae for wattage per day over the whole grow to find my actual wattage used. Or is just dividing weight into final wattage how every one figures it to keep it simple.

I’d really like to get my total wattage per gram figured out eventually. Since all
The fans and pumps are constant I just need to get the lights sorted. Might be a program on the kill a watt but damped if I could figure it.
 
Regarding "find[ing] my actual wattage used," that should be the sum of all power levels used/hour (your draw in watts) times no. of hours, getting you to (kilo)watt-hours, which is how electricity is charged.

From my perspective, you are at 1.45 grams/watt. I would want to use the bloom, the maximum watts number for the calculation.

But can you explain why grams/watt is important? To me, it is 1 way of measuring plant productivity, basically not all that different from reporting grams/plant. Comparing different growers' grams/watt is not done all the often, with so many other variables involved other than light wattage. So what is quantifying grams/watt to 1/100th of a gram actually useful for?

None of your light height data are relevant to determining "wattage used;" with height more related to light intensity experienced by the plant (measured other ways).
 
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gram/watt is a meaurement of how good the light is,the grower is,or a value for money type thing ?
i think the watts of all grow equipment should be included fans,humidifiers,heating,cooling :shrug:
is there a variation in the formula for a perpetual grow ?
:pighug:
 
GPW it's useless anyway. More accurate would be grams per kWh, with all electricy consumed. But no one has time for that.
I achieve pretty great GPW result from my DIY COBs, from 2 GPW to 3 GPW and even more. It's nice to see, but it's useless anyway.
 
Guess it’s not all that important since I know my grows are pretty cheap. Since I joined this site I’ve seen GPW used by light companies as what seemed like a benchmark?
Just happy they stay green
 
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