[madgiz]

I think the difference in the terms we are thinking is that I am talking about a benchmark and not an exact science..

Where I think the GPW would be more exact is if every grow room had a separate flower room and that the GPW is taken from that.. So it is a measurement of the efficiency of your room to flower and finish plants under a set wattage of light..

Then you could even divide by weeks for long flowering plants and have a truer benchmark with GPWPW..

This post has been edited by madgiz: 19 April 2012 - 03:01 PM

[MED]

not sure why your so hung up on time,... surely cost is the most relevent factor for comparison?

[chalkywhite]

Given that both are using the same set ups etc. Longer time = Greater cost MED..

[MED]

chalkywhite, on 19 April 2012 - 01:12 PM, said:

Given that both are using the same set ups etc. Longer time = Greater cost MED..

thats my point bud. many factors will make time more expensive for some and cheaper for others. sorry should have been clearer

[madgiz]

It is still a goal to strive for no matter which way you look at it for new growers to achieve a gram of bud per watt of light..

E2a ...and that is why I think it is still a good benchmark but obviously as you improve as a gardener you can move the goal posts to fine tune the equation..

This post has been edited by madgiz: 19 April 2012 - 01:19 PM

[MED]

completely agree Madgiz

right now i just want my grow to finish so i can get my smoke on hahahaha

what about a How Stoned Per Watt?

[FAI]

MED, on 19 April 2012 - 01:05 PM, said:

not sure why your so hung up on time,... surely cost is the most relevent factor for comparison?

Yes....the cost of having your lamp switched on; which is a time thing surely.


I take your points there madgiz....and this is what I'm getting at. For it to be a useful assessment a grower must consider the time taken to achieve a particular result.

Take this further example: a grower gets 300g from a 12 week cycle using a 400W = 0.75g/W.
He alters his set up decides to do things differently and gets 400g in a 24 week cycle = 1g/W. The guy is over the moon because he's hit the magic figure; when in fact he has gone backwards by producing only 25% more bud in twice the time.
Yes, my example is extreme...but it illustrates where my thinking and resoning comes from.

[MED]

FAI, on 19 April 2012 - 01:24 PM, said:

Yes....the cost of having your lamp switched on; which is a time thing surely.

yeah bud,.. were on the same track not everybody pays the same for leccy tho so i would put cost above time.

[madgiz]

Hey I would like to think that we are all singing from the same hymn sheet..

Although as we all know it is not a given certainty no matter how long you veg for that you will get a gpw as that is still a lot of bud to finish under a set amount of light..

But as benchmarks go it beats the old ones like ounces per plant..

[Joint hogger]

I see what your getting at FAI & your right, the extra vegging time added to the overall costs,
normally if i veg for 4 weeks & flower for 9/10 weeks & add a few weeks to dry properly it normally
costs me roughly £140 in leccy charges, £20 for PM soil & nutes, so if i normally get 10oz per grow,
it cost me £ 16 per oz or less if the yield is higher.

in the above mentioned grow, i vegged for another 6-8 weeks in the veg cab & it cost me an extra £30
so that takes it up to about £190, so it now cost me just over £11 per oz, if i was just to do 4 perpetual
grows per year, i'd be looking at 40oz + & it should cost me £560 per year, but if i was to get similar
results to this grow by giving the plants a longer veg time, it would work out at 17x3= 51oz - x£190 = £570.

This post has been edited by Joint hogger: 19 April 2012 - 01:47 PM

[MED]

£16 per ounce sounds bloody good too

some wonky maths there tho

This post has been edited by MED: 19 April 2012 - 02:09 PM

[SuperK]

Joint hogger, on 14 October 2011 - 10:48 PM, said:

this is something i've never managed to achieve in the past when i was using a powerplant reflector (similar to a Euro Reflector)
with a lumatek 400w,7200k mh for 6 - 10 weeks training then under a son T to finish off.
& for the last few years now, i've been growing the same 2 strains (anaesthesia & big buddha's blue cheese)
so im getting to know how they grow & what they like or dont like, also i vary how many plants i grow
each time to see whats the best combination for me (6 to 8 in a 1m tent)

for the last few grows using the powerplant relector, i averaged roughly 10 to 12oz & my best attempt was 13,
364g X 400w with a ratio of 0.85, not bad but i was determined to improve things, especially after i helped a pal set up
with a 600w parabolic & the bugger pulled just over 21 1/2oz with his first attempt



so the powerplant was put into retirement & i got the smaller 80cm parabolic & i've since completed 2 grows with it,
the 1st grow, i had 3 of each in 11ltr pots & after a long veg & 9 weeks of 12/12, i got just over 13oz,
372g x 400w = a ratio of 0.93 not bad but i still wanted to improve it.

with the last grow, i went with 8 plants in 6.5ltr pots,same again, a long veg, a bit of fimming to keep things in check,
but i decided to go for a slightly longer 10 weeks 12/12.

heres them after a few weeks under the MH



here you can see them a few weeks into 12/12 & the tent is filled out nicely



Anyway, after 4 weeks drying in the tent, it was bone dry when i chopped them

so, i got the scales out, did the business & couldnt believe it, recalibrated the scales & paid closer attention,
well, i've only just managed to pull just over 17oz or 480g to be precise, a ratio of 1.20

Go you Effin Beauty


i was considering on changing the parabolic for something which better suited my 1x1x1.8m budbox too
but i think i'll just keep a hold of it now


atb JH

Fairplay to you mate excellent haul hope all your grows go well like this one, you obviously got better ith each attempt and now have I suspect maximised your growing potentialf rom the equiptment an space you have. The mark of a truely good grower. Respect-I too am trying for this GPW mission but as its my 1st real go atm Ill hold back expectations for now, like you i aim to improve with every next run untill becoming completely self sufficient. S.K

[bigstevo]

If you wanted to take time into account you could do it like this.

(Kw per hour) x (hours of lights on) x (days under lights) / (grams of dried bud)

E.g

0.4kw x 18 hours x 70 days veg = 504
0.4kw x 12 hours x 70 days flower = 336
336 + 504 = 840 kw hours
480 dried bud / 840 kw hours = 0.57142857 gpw

To measure your own efficiency when changing either watts/veg or flowering time then the above method is the only way to compare apples with apples, so to speak.

This post has been edited by bigstevo: 21 September 2012 - 09:37 AM

[Mephitis]

Gram per watt? Doesn't bother me, as long as I have enough to get me between harvests I am a happy man.

[bigstevo]

what was the actual period of veg for both grows? and the lights used for veg out of interest?

This post has been edited by bigstevo: 21 September 2012 - 09:26 AM