HPS vs CFL for SMALL boxes

Hello, guys.
No, this is not quite the same topic about HPS vs CFL. Personally, I do think that HPS are better choice for big boxes, because you just need to install one or a couple (ok, or a few) of HPS lamps and that will be great, and you will not need to spend time installing tens of CFL lamps and consuming 1.5 times more energy.

I am from Russia and I don't know about this forum and other regions, but in Russia growing in small boxes (a.k.a. micro growing, or stealth growing) is quite popular.
Why would someone want to grow in a small box to get 10-20 grams of weed? Well, for some people that will be enough for a year (or two)! Other people just don't have place or possibility to use big boxes.

*And yes, I know, that HPS are more efficient, that is why to make a fair compare we need to compare lamps that give same amount of light (in lumens).
As I see HPS usually gives 1.5 times more light than CFL (although if you take poor HPS lamp and best CFL lamp they will give same amount of light, but let's take that usually HPS is 1.5 times more efficient).
So what is better for growing in a small box: 100W HPS or 150W CFL? They both give same amount of light.
What is a small box? Well, let's say it's 1.5'x1.5'x3' (45x45x90 cm)

Here is what I personally think (I may be wrong):

CFLs advantages for small boxes:
- CFLs are cheaper
- CFL are easier to find and buy and it's ready to use
- CFL can have better light temperature (you can find it 2700K, you can find it 6500K, and for example Phillips 100W HPS lamp that is popular in Russia has light temperature of 2000K, which seems not ideal for flowering (given that ideal is 2700K))
- CFL can give better light distribution (I think 3 x 50 W CFL will distribute light better than 1 HPS lamp)
- CFL can not burn your skin

HPS advantages:
- Takes less space (1 HPS lamp will take less space in a small box than 3 CFL lamps)
- Takes less electricity (though there is not a big difference when we talk about 100 vs 150 W and in some countries, like in Russia, electricity is cheap)
- Maybe lasts longer (I am not sure)
- Damn, so many growers recommend it.


No, I am not a fan of CFL lamps. I'm just a beginner who wants to understand what is better for a small box (and by better I mean bigger yield) and if there is any real difference at all!
I tried to search web for a few hours but I didn't find really adequate experiments. I found a few experiments where people compare yields under HPS and CFL but they use different amount of light! For example, on this forum, one guy showed his yields from HPS and CFL, and HPS yield was better but he used 600W HPS and 360 W CFL, that's absolutely not fair. On youtube I found another compare, but again, the guy used 400W HPS and 200W CFL, damn that's not smart.

So, what is your opinion? And please, together with your opinion add some arguments, facts, numbers, links, etc.

CFLs advantages for small boxes:
- CFLs are cheaper - They are cheaper upfront, but down the road may cost you more in electricity/replacement costs.
- CFL are easier to find and buy and it's ready to use - if ready to use you mean rigging up multiple light plugs into your box, then yes. An HPS is literally ready to go out of the box except hanging it. Same amount of work really.
*- CFL can have better light temperature (you can find it 2700K, you can find it 6500K, and for example Phillips 100Wt HPS lamp that is popular in Russia has light temperature of 2000K, which seems not ideal for flowering (given that ideal is 2700K)) - You can find HPS by Sunpulse (http://www.sunpulselamps.com) and they come in 3k, 4k, 6.4k, and 10k Temps.
- CFL can give better light distribution (I think 3 x 50 Wt CFL will distribute light better than 1 HPS lamp) - Depending on the style of bulb, you are using the box to reflect light, and they bulbs are bult around each other in tubes making some of that light go into the middle of the bulb and be wasted.
- CFL can not burn your skin - 100w of HPS says you'd have to be pretty out of it to get burned.

HPS advantages:
- Takes less space (1 HPS lamp will take less space in a small box than 3 CFL lamps) - Probably not by much, if at all.
- Takes less electricity (though there is not a big difference when we talk about 100 vs 150 Wt and in some countries, like in Russia, electricity is cheap) - This will add up over multiple grows, saving you money and cuts into the "upfront" cost that scares most people away. Think of paying 1.5x electricity for as long as you grow.
- Maybe lasts longer (I am not sure) - They last over 2.5 times as long - CFL = 10,000 hours, HPS = 24,000 hours That means each CFL lasts about a year before needing replaced.
- Damn, so many growers recommend it. - It really does create more intensity from a smaller area, thus denser buds.

So lets say you grow for 2 years and over the 2 years that costs you $1,000 in electricity to power the CFL. It would have only been $750 from the HPS. Now, every year you have to replace the CFL. I think 50w CFL run about $15, so every year that's another $50 in replacement. Over the 2 years you have saved $350 AND produced thicker, better buds with a higher yield. The production of extra weight and better buds will pay for itself in the first season.
In my humble, humble opinion I believe there is no reason to use CFL during flowering unless you are THAT strapped for money upfront that its your only choice. Even then, I would probably opt to not do it just because of what I've seen HIDs do over the years.

CFL's loose their brightnes RAPIDLY, which is the only reason I think LED's will replace them in the long term in regular applications.
Ultimately you have to look at how much light you get per Watt. (yes, its written with a capital letter).
No matter how many cfl's you add, lumens do not add up, i.e. its no brighter to the plants (of coarse you can probably reach more chlorofil areas with multiple bulbs).

Thank you for joining the discussion, guys.

Dubdeuce,
>100w of HPS says you'd have to be pretty out of it to get burned
Sorry, with my far not perfect English I am not sure I understand what you mean. I've read that people got burned with 150W HPS.

As for electricity - sometimes it doesn't really matter. For example, I just pay a fixed price for my electricity - about $15 a month, yep we have such laws in Russia, you can choose if you want to pay by meter or just fixed price *And even if you choose to pay by meter, it costs about 6 cents for KW, so if decide to grow a couple of times per year, than the difference between 100W HPS and 150W CFL will be around $10.

As for changing CFL bulbs more often - well,
first, it seems you didn't count that you would need to change HPS after 2 years also;*
second, I would not like to talk about serious growing here, otherwise we wouldn't talk about small boxes. And if you want to grow like only 2 times a year (that may be really enough for a small company of friends who just smoke once a week or even more rare) then you will not need to change your bulbs often.
third, in this discussion I would like to understand if it is possible to grow same amount of good weed with 150W CFL as you can grow with 100W HPS, so at least for me cost of CFL bulbs doesn't really matter..

>It really does create more intensity from a smaller area, thus denser buds.
Can you prove that 100W HPS will create more intensity than 150W CFL?
As I understand, light intensity is amount of light for some area, amount of light is measured in lumens, amount of light for sq.m. is measured in lux. And 150W CFL can give you same lux value as 100W HPS. You can see it in these experiments:*
https://www.rollitup.org/indoor-growing/83128-lumens-lux-adding-all-up.html
https://www.rollitup.org/indoor-growing/83378-16k-lumens-hps-vs-cfl.html

ANC,
>CFL's loose their brightnes RAPIDLY
I believe that light spread in the same way, not depending on the type of the light source. It's all light. And I think you know there is a law that amount of light is decreased by 4 times if you move 2 times further away from the light source. And I believe this law is the same for any light source.
Also, you can see the second link above and see in the graphics that for CFL light doesn't loose its brightness more rapidly than for HPS.

>No matter how many cfl's you add, lumens do not add up, i.e. its no brighter to the plants
That is wrong, you can see the experiments in the two links above and I also found some discussions on other forums, for example here:
http://www.candlepowerforums.com/vb/showthread.php?189362-Do-lumens-add-up

Anyway, what bothers me most is not total cost of electricity or bulbs, but, I will repeat,*if it is possible to grow same amount of good weed with 150W CFL as you can grow with 100W HPS?

ANC said:

No matter how many cfl's you add, lumens do not add up, i.e. its no brighter to the plants

Click to expand...

This is wrong. It's been proven wrong, and is also contrary to the laws of physics (and common sense for that matter). I don't know why some people keep saying this. Of course lumens add up, when focused on the same point. If you have one lamp in a 2'x2'x2' box, you really think it's not gonna get 10x's brighter when you add nine more bulbs? Where does this additional "mystery light" disappear to? Please stop giving misinformation people.

Ok, guys, I have a nice video for you, though maybe some of you have already seen it. It's in russian, but it's easy to understand what's going on and the results are shown.
Here is the video:
http://www.youtube.com/watch?v=bqE-wNJupV8
In this video they compare 2 lamps (CFL and HPS) with the same power input (their meters show about 112W). Then they meter*illuminance on 3 different distances from the lamps and show the results.
The results are:
About 1 meter (3.3 ft) from the lamps: 3300 lux for HPS and 2300 lux for CFL (HPS gives 43.5% more light)
About 50 cm (1.6 ft) from and directly under the lamps: 10100 lux for HPS and 7700 lux for CFL (HPS gives 31% more light)
About 50 cm (1.6 ft) from the lamps on the box sides: 4180 lux for HPS and 3300 lux for CFL (HPS gives 26.5% more light).

So, the average result of their experiment is that HPS gives about 35% more light than CFL.
So, yes, HPS is more effective when power input is the same. But in this thread we want to compare 100W HPS and 150W CFL and as you can see after watching this video, it is possible that 150W CFL can outperform 100W HPS, so the question about HPS vs CFL is open and very interesting.

PS. In the second part of the video they compare temperatures on the distance of about 50 cm (1.6 ft) from the lamps after 2 hours in closed boxes. CFL box shows 46 degrees Celsius and HPS box shows 43.6 degrees Celsius. Though I think they also needed to compare the temperature closer to the lamps. But still, some information..*

PJ Diaz said:

Where does this additional "mystery light" disappear to?

Click to expand...

Maybe photons from different lamps begin to fight with each other for taking the space and die in the fight?