Actinic linear flourescents.

I'm all about spectrum and PAR but I'm having a really hard time justifying these to myself. It reasons that if you have a small limited space then the actinics could yield more per area than standard 6500K/2700K but the numbers just don't add up when it comes to yielding better $/gram.

I threw together a few spread sheets comparing the two and by the end of a few grows the cheap bulbs win $/g. I went through several threads where people use these bulbs and picked out a few of the more popular bulbs I have read about - 8 bulb 4'T5 grow with 2 coral wave, 2 fiji purple, 2 florasun, and 2 cheap 6500k/3000k fixture versus the same fixture with just cheap bulbs. I ran my spread sheet with the actinics yielding .6g/w and the cheap bulbs yielding .48g/w which is a 20% reduction in yields, I assume this to be fair but correct me if I am off. I also compared using a 40% decrease in yield which I cannot imagine, but the results ended up being about the same versus the actinics.

If you run twice the amount of cheap bulbs after 5 runs you'll pay $150 more (mostly for the additional fixture) but yield over a pound more with the dollar to gram being much more favorable (25% savings). These are based on changing the bulbs every third grow but I have also included the numbers for changing the actinics every 5 grows - you can compare this to changing the cheap bulbs every third grow section and see that you are still better off $/g with the cheap bulbs yielding 20% less.

Really not trying to bash these but am I way off? Do they actually compute $/g and not just gram/m2?

I apologize in advance for my sloppy chart layout - I've tried to bold some of the important numbers - total cost at end of 5 grows, $/g, and total projected yield.




So if you compare the 1st row and third row you can see that you may be able to yield more off one fixture but you are paying quite a bit more per gram of bud than the generic bulbs. I would assume that down the line running 2x the light would be around the same total cost, yield significantly more over the same time period (37% gain in yield), and you would be paying much less $/g (25% savings).

Electric is based on $0.12/kWh with a 60 day flower period.

A lot of time was spent on this, at least you confess up front that the numbers were pulled out of your ass. I'll treat this as a humor post.

Phaeton said:

A lot of time was spent on this, at least you confess up front that the numbers were pulled out of your ass. I'll treat this as a humor post.

Click to expand...

What numbers? The .6g/kWh is what I have personally yielded from flouros - most everyone else I know yields ~ .4. I have heard a reported 20% increase from actinics but also included a 40% for the heck of it - I asked to be corrected if this is off. The prices are straight from online vendors and the price for the power is the average of what I pay locally. 60 days is how long I flower for and every third grow is how often I change my bulbs.

Thanks for contributing with your personal experiences with actinics...

I am looking for someone to provide me evidence otherwise. I would love to be convinced I am wrong so that I can improve what I have now.

Lost me there. Science doesn't try and prove anything. Math is a great tool for comparing numbers - bit hard to compare without it.

most of what i've read is that actinics cost way more but produce a bit more watt/gram though the 27/65k's cost a lot less and make a little bit less per the ratio. To me it kinda evens itself out in overall cost. i'm currently pricing out a 2'x 4 bulb T5 fixture myself, hopefully my girl got me 1 for xmas lol

happy growing

Gastanker, how did you assign grams/watt to the bulbs? Imo this is the one variable that could make or break your model.

I also want to thank you for the effort you put into this ... it is messing with some of my preconceived notions. cn

cannabineer said:

Gastanker, how did you assign grams/watt to the bulbs? Imo this is the one variable that could make or break your model.

I also want to thank you for the effort you put into this ... it is messing with some of my preconceived notions. cn

Click to expand...

I was able to yield .54g/kWh with CFLs. Most flouro grows I've seen, if they veg intelligently and do not veg too long, yield around .4g/kWh - this is not too bad and actually compares fairly well to HID growers when comparing g/kWh and not g/w. I assigned .6g/kWh for the actinics as I know it is possible and imo is on the high yield side of flouros. The regular bulb g/KWh is 20% and 40% less than the actinic yield - .6-20% = .48, .6-40% = .36.

The 20% and 40% increase in yield is made up - I have never seen anyone running actinics actually show that they out yield standard 6500k/2700k. I assume they if they do indeed yield more it would be around 10% more, I made the charts at 20% just to be generous and 40% just to prove exactly how much more efficient they would really need to be - 40% increase in efficiency makes the $/g ratio the same between standard bulbs and high priced bulbs if you change the cheap bulbs every other grow and the high priced bulbs every fifth grow. I can't imagine an actual 40% improvement in yield when rarely changing your bulbs.

You should be able to adjust the g/kWh to lower or higher and it should show the same results as long as the actinic yields and standard bulbs yields correlate via a % increase/decrease. Let me know if you want the g/kWh adjusted. I've been asking people that grow with these higher priced bulbs and none can give me a number on how much their yields have actually increased... If someone can show me that the actinics yield 50% more then by all means I want some.

Oh I see now ... you are modeling weight/energy and not weight/power. It's the more informative measure but not the conventional one imo ... cn

cannabineer said:

Oh I see now ... you are modeling weight/energy and not weight/power. It's the more informative measure but not the conventional one imo ... cn

Click to expand...

It's more informative in that it takes into consideration the differences in veg and flower time. Here the veg and flower time is a constant so I could easily change the figures to g/w and it would still read the exact same. Reported yield might change but the reported % difference in $/g should still be the same. If you would like the same chart converted to g/w versus g/kWh let me know and I'll upload it - very simple revision, instead of 311kWh it would be 432w.

I feel g/kWh also makes it much easier when comparing additional light - you need to keep the cost of running the additional bulbs in check with the rest of the math - of course i could calculate electrical costs in kWh and base yield on g/w light output, pointless imo but let me know if you want the chart that way.