Amount of light vs. heat generated

[DasPachy]

Growing in 2ft x 1ft footprint, 3ft vertical space (6sq ft). Want to run 12 30watt CFLs. Temps between 72 and 78F currently running 6 23watt CFLs. I know CFLs do not create much heat, but that many is bound to create some. Anyone have any guesses as to how much? Options are 50 or 70CFM fans. Think 50CFM would be enough to suck out a lot of the heat?

[Revanche21]

not enough to really worry about

you can touch CFL's even after they have been on for hours without getting burned

I would guess that you wouldn't need too much for ventilation

don't take my word for it tho

[DasPachy]

Bump for anyone with experience in such matters :)

[dgsgandalf]

Actually, 50cfm is practically nothing, but for your space it might work... It's always good to have too much than too little ventilation.

360w of cfl in a 6cf area is probably going to get pretty hot. Test your setup before you start planting anything so that if you need more ventilation, you can add it. Temperatures should be 70-85 degrees F. Too far below 70 or above 85 will stress the plants and reduce your output.

[Roughrider]

360w of CFLs in 2 sq. ft. of surface area is overkill, big time. You don't get as much canopy coverage with CFLs...but you've got a small space to begin with. Frankly, I'd be thinking 6 CFLs with that amount of space...maybe 8. 8 23w CFLs is going to put out around 13000 lumens in 2 sq ft. ... 6500 per sq. ft. That's more than enough for a grow. Fewer lights also = fewer problems with heat and ventilation, so you can make it easier on yourself there, too. I'd imagine a 50CFM fan would be fine.

[DasPachy]

Currently running 6 23watt CFLs for veg with only a cracked open cab door and a processor fan for circulation (no powered exhaust or intake) - temps stay a pretty consistent 74-77F. That's why I thought maybe with a 50 CFM I could get away with the 12 30watters, but RoughRider makes a good point. I'd still really like to run the 12 30watters but maybe I'm getting a little greedy for lumens? Just really want a decent sized, good quality crop.

[DasPachy]

If heat were controllable, would there be any reason not to?

[MaryJaneMonkey]

Instead of shelling out all the cash for a dozen 30w, why not just buy a 150w hps, which would IMO be a lot better than all those CFL's.