CFL Tutorial

thenoffya

I am a CFL grower by necessity, and I have done a bit of research on them as a result. I hope you will find the following information helpful. Please note that this is not an argument for CFLs versus HID lighting versus LEDs. This is merely for informative purposes.

4240_cfl.jpgGE bulb.jpg

Pros and cons of CFLs
Pros
Cheap - most regular size bulbs cost less than $9
Low heat per bulb - most bulbs can be touched while lit, and can be moved closer to plants
Maneuverable - plants can be literally surrounded by cfls
Available - can be bought in almost any large retailer and many supermarkets and drugstores
Simple - no exterior ballast needed, fits into most regular incandescent sockets

Cons
Medium amount of lumens – multiple bulbs are needed to equal output of HID lights
More heat per watt than HID, albeit possibly spread out more
Depending on the setup, possibly complex wiring issues
No standard color temperature language yet

Background
The compact fluorescent was originally invented at GE in 1973. However, they were not really mass produced until 1980, and have only gained popularity as of late, due to being "green" or environmentally friendly. CFLs work the same way that regular fluorescent lights work. A sealed glass tube containing an inert gas, usually argon, and a small amount of mercury, is kept at a low pressure. The glass tube is also coated on the inside by a phosphor powder. On each end of the tube is an electrode. When a current is sent through the tube, it shoots from one end of the tube to the other in the form of free electrons, the basic unit of electric current. When these free electrons collide with a mercury atom, the electrons revolving around the mercury atom gain a relatively huge amount of energy, and jump up to another energy level. However, it cannot stay at that energy level for long, and when it drops back down, it emits a photon. In this instance, the mercury releases a photon in the ultraviolet wavelength. This photon strikes the phosphor coating of the glass. The phosphor atoms do the same thing as the mercury atoms, in that one of their electrons absorbs the energy from the photon, and spits it back out, this time in a wavelength that we can see. The light spectrum depends on the type of phosphor used to coat the glass. Since the light produced is usually of a narrow wavelength depending on the phosphor, most fluorescents have more than one type of phosphor. Using different phosphors varies the light emitted.


Wattage
One common mistake is not knowing what a bulbs actual wattage is. A few months ago, on another site, I saw a post that was titled something like "Check out my new grow, 800 watts of cfls". When I clicked on the link and began reading, I noticed that the person had mistakenly thought the INCANDESCENT EQUIVALENT of the cfls was important to growers. The person only had about 200 watts of power, and got verbally abused for not knowing the difference. The producers of cfls are the ones who are really at fault here, because almost all packaging has the incandescent equivalent of the bulb marked prominently. That number is not important for growers, though. The important numbers are the actual wattage and the light output, or lumens. The actual wattage is what you will pay each month in your electric bill to run the bulb. In general, the actual wattage is about one fourth of the incandescent equivalent.
A.jpg
Because of differing efficacies (see next section), watts per area do not make sense as a general rule of thumb. Instead, it is the lumens per area that is important.


Lumens
Without getting too scientific, lumens are what make a plant grow. In general, the more lumens shining on the plant the better. Much of what I have read says 1000 to 2000 lumens per square foot for vegging, and 3000 to 5000 lumens per square foot for flowering. In general, most cfls have a lumen/watt ratio, or efficacy, somewhere around 65, but usually between 55 and 75. Smaller cfls general have lower efficacies, and larger cfls have slightly higher efficacies. This is great compared to incandescent bulbs, which average between 8 and 20 lumens/watt. However, it doesn't hold a candle to hps and mh lights, which usually get between 100 and 150 lumens/watt.
B.jpg
So cfls are fairly efficient, but you need multiple cfls working together to grow.


Cost
To calculate the cost of using a cfl, or anything that draws power, divide the wattage of the cfl by 1000. Next, multiply that number by the number of hours per day the light is on. Then, multiply by the number of days in your billing cycle. Finally, multiply by the cost of electricity in KWHr (Kilowatt Hours), which should be stated on your bill. This is what it costs to run that single bulb for a month.
Example: My current grow has 6 30 watt bulbs = 180 watts running 12 hours a day. December has 31 days, and I'll assume my cost of electricity is 14 cents per KWHr. I then have a bill of 180/1000*12*31*.14 = $9.38.
It is simple, really. Note that since cfls save electricity and therefore, money, putting cfls throughout your house or apartment can completely eliminate the spike in the electric bill from growing!


Heat
Just because you can grab a fluorescent tube without being harmed, does not mean you can do it with cfls. Because the tube is coiled around itself, it creates more heat in a much smaller space than a four foot tube. That is not to say that it gets even close to as hot as an incandescent bulb. But for safety, I would recommend letting any bulb over 25 watts cool a little before touching. Also, I wouldn't let my plants touch any bulb larger than 13 watts. Remember, ventilation is extremely important.


What the heck is color temperature?
Technically, color temperature means the temperature of an ideal black body radiator at which the color of the light source and the black body are identical. (A black body is a theoretical radiator and absorber of energy at all electromagnetic wavelengths.) Thus, for a 2700K light bulb, the blackbody would be 2700 Kelvin, or approximately 4860 degrees Fahrenheit. What does this mean to a grower? A plant in nature is used to different having a cycle of light throughout its life span. Beginning in spring (fall in the southern hemisphere), the plant is subjected to many long days of light at a high temperature, usually between 5000K and 6000K. This light is very white, and somewhat bluish. Later in the plants life, it sees more and more red light, which helps it to know when to flower. The scientific reason for this is that during shorter days, the sun is not directly overhead, and due to the wavelengths of light, more blue light is bounced off the atmosphere than red light. Some people think backwards (helped in part by the producers of cfls, see below), that a red color is hotter than a blue color. If you light your lighter (I'm sure most people reading this have a lighter), you'll notice that the flame is blue at the bottom, where it is warmest, and yellow at the top. The reason you won't see any red is that the gas burns too quickly for the flame to be red. However, the red can be seen in a fire. Note that in the picture below, the top of the list on the right coincides with the bottom of the color scale.
C.jpg

So which bulbs should I get?
For vegetative growth, you will want bulbs which are at the high end of the spectrum (5000K to 6500K). For flowering, you will want bulbs at the low end of the spectrum (2700K to 3500K). Unfortunately, some manufacturers think that the color spectrum is too confusing for people, so they came up with other words to describe the color spectrum of the bulb. The typical incandescent bulb is 2700 Kelvin and produces a "Warm white" or "Soft white" light. At 4000 Kelvin, a "Cool White" fluorescent light is sometimes called "neutral". A "daylight" fluorescent light is rated at 5000 to 6500 Kelvin and provides cool light with a blue tint. Notice that a "cool white" bulb emits light at a hotter temperature than a "warm white" bulb. Confusing, huh? Note that the light temperature does not affect the temperature of the bulb itself. Also, be aware that the phrases used above are not standard. For example, Sylvania "daylight" bulbs are rated at 3500 Kelvin. This confusion will be coming to an end soon, though, since Energy Star 4.0 guidelines will require labeling all cfls with the color temperature.

__________________
Jock Horror in Rubbermaid Grow Box - First Grow - Exactly what the title says.

Jock Horror in Rubbermaid Grow Box - Second Grow - This one isn't a lie either.

godspeedsuckah

I would like to use cfl's for supplemental lighting with my 400w hps. Do you have a preference as to which light would be a good match with my hps?

knottyd

Some people use MH for veg and HPS for flower. So If you want to mix it up i would add some CFL's int the 5000-6500 range which will give you more blue light to balance it out a little ( not literally as it wont be EQUAL but your adding a different color). Some people also dont really add blue to red or vice versa. Its just about what you want to do. me personally I add the opposite of what I'm running ( I have a MH bulb in now and added red spectrum CFL's, I'll be switching soon to my HPS bulb and adding blue spectrum CFL's) either way your gonna be good to go. ALL the info you need is on this page. It ultimately comes down to personal prefference

__________________
I may say or do things to get you to like me, that includes lie, cheat and steal. So i'm going to appoligize now if somethings I say or do turns out to be a lie. I may lie, cheat, and steal..BUT I WOULD NEVER BREAK THE LAW!!!!

Canna Bus

I use T5 CFLs and nothing else from start to finish. I keep the lights 2 to 4 inches from the tops and go to 12/12 when they reach about 8" high.

For SoG go to 12/12 when they reach about 5" high.

I like growing in soil (Ocean Forest).

My girls are very happy, healthy, beautiful and bountiful.

Having said that I want to add that when my girls reach about 3 inches tall I begin spraying with Spra n Grow every other week up until a week before harvest.

And alternatively at the beginning of 12/12 with Purple Maxx up until two weeks before harvest. I add Coco Wet to both solutions for best coverage.

My grow space is small - 2 x 4 x 6. The Walls are Astro foil which is Mylar covered bubble wrap.

-------------------------------------------------------------
For the less experienced, no matter what lights you use, everything else has to be done right too. Read-up with Jorge Cervantes and Ed Rosenthal.
--------------------------------------------------------------

I have the Sun Blaze 4 foot 8 tube T5 unite. I like that it has two switches on the front that allows you to use either four or eight lights. I use the center bank of four with seedlings and then when they get a little bigger I hit the switch and give them all eight.

Peace,

Canna Bus

702puffin

i jst started my closet and ws woundering if any one has seen the aug issue high times wher they show some one use Y conecters 3 per light source alowing you to plug in 4 cfl's. my space is 3 x 4 x 6 was woundering how many bulbs ide need by the end and if you sujest using 4 floresent tubes verticaly to box in give more lumin to my kidz.

kailiwela44

The bigger she get, the more she needs. If possible, sorround the plant entirely with cfls rated at least 26watts--remember to keep them within a few inches paying close attention to not burn the leaf tip excessively. If you can't, try to get at least the canopy well lit and and add a couple cfls for extra side lighting rotating 90degrees either daily or every other day allowing equal lighting to the plant--see more buds style.

kailiwela44

__________________
Citral CFL
http://www.greenpassion.org/f22/cfl-...617/#post56555

s33ds209

now do i use all warm white (2700k) cfl's to flower my baby or should i mix it with daylight(6500k) cfl's?? and how long do i use fertilizer while flowering?? up until its time to chop them down??

scott06

you can mix or go with just the 2700k - I would make sure 2700k predominates if I blended the spectrum....your choice however is entirely personal as peeps have success either way

as for nutes...you have to tailer it to how the plants are responding but genrally folks seem to end nutes (Except Molasas) a week or two before harvest with a good flushing...again people are successful with many methods and it is a personal choice..... with nutes it seems almost everyone over fertalizes at some point, but few people ever under fertalize....

s33ds209

thanks scott, i think im gonna go with two weeks before.just to be on the safe side.as far as the lights go,im gonna do 3 2700k cfl's and 1 6500k.thanks again.what about the molasses??is that something i have to use??

kailiwela44

You don't have to, but it makes a big difference. Probably helped my yield in my high heat enviroment.

kailiwela44

__________________
Citral CFL
http://www.greenpassion.org/f22/cfl-...617/#post56555